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Synthesis of methanol from captured carbon dioxide using surplus electricity
Periodic Reporting for period 3 - MefCO2 (Synthesis of methanol from captured carbon dioxide using surplus electricity)
Reporting period: 2018-06-01 to 2019-06-30
Aim: develop an innovative green chemical production technology contributing to the EU objectives of decreasing CO2 emissions and increasing renewable energy usage improving Europe’s competitiveness.
Concept: ordinarily emitted CO2 and H2 produced from surplus renewable electricity into methanol. Technology designed in a modular intermediate-scale, able to adapt it to varying plant sizes and gas composition.
-Mitigation of exhaust CO2 and reduction of GHG by replacing methanol produced from fossil fuels (NGV or coal) with methanol produced from CO2 and renewable energy.
-Stabilisation of electric grid by the consumption of the electric energy at its peaks. MefCO2 allows to increase the power supplied from non-manageable renewable energy resources since surpluses can be used to produce valuable methanol. Fast ramping electrolysers provide ancillary services and replace fast acting fossil generation such as gas turbines.
-Production of methanol as a versatile chemical for further conversion. The EU is a net importer of methanol and MefCO2 results contribute to the reduction of imports. Low carbon footprint methanol can be directly blended with gasoline or transformed into fuel additives (DME or MTBE),reducing fossil fuel imports and improving air quality due to the improved combustion. Depending on the CO2 source, MefCO2 low carbon methanol and fuel derivatives could comply with the RED requirements and be considered as renewable fuel of non-biological origin.
Conclusions: the technology has been successfully deployed at RWEs lignite fired power plant in Germnay producing up to 1 ton of methanol from1.5 tons of CO2 captured. MefCO2 technology can be adapted to any CO2 source either from fossil origin such as steel mills, cement kilns, refineries, power plants, etc. Key components of the pilot process were a fast acting PEM 600kW electrolyser able to ramp up or down H2 production within seconds. This flexible operation is highly suited to adapt to power prices created by fluctuating renewable power and for grid stabilisation contributing to the increase of renewable power in the grid. A fast response rectifier patent was filed. Other key component is a methanol reactor able to modify its output (demonstrated in test campaigns). Unlike standard chemical process designed for steady operation, MefCO2 reactor was steadily operated not only at its nameplate capacity but also at 40% of it. It was able to ramp up and down production within minutes. The modular reactor design can be scaled up and plant output can be adapted. The combination of fast ramping a electrolysis unit and a flexible methanol reactor allows MefCO2 concept to operate without oversizing the electrolysis unit and using intermediate H2 storage that would be required in a conventional methanol plant. Methanol produced from renewable energy for H2 production turns into an energy vector for renewable energy storage with higher energy density than H2 that is easily stored and transported. In terms of novel catalyst development and process optimisation through multiscale process optimisation, a comprehensive work was carried out. More than 100 catalysts were synthetized, characterised and tested in different operation conditions. A patent for a new method of synthesis for high performance catalyst was filed.
Pilot Plant:Methanol production: 1t day/CO2 capture: 1.5t day/PEM electrolyser 600kWel with improved dynamic response: 120 m3/h
Test campaign under flexible operation conditions:Conversion efficiency exceeding the design criteria: 97% vs 91% (55 kg Crude MeOH/h)/Dynamic Operation performance improving design criteria: 40%/min. vs 20%/min (Loop reaction time from 5 to less than 3 minutes)/Flexible Operation demonstrated.
LCA&Thermo-economic analysis:Net emissions of methanol production are 68% lower than SMR’s process when wind power is used but using German grid power results into a more than 2x increase/Business case supported on simulations for technology scale-up
Novel catalysts & overall process engineering improved:More than 60 catalysts synthesised and tested/Patent Pending GB1701382.2 – Catalyst suitable for methanol synthesis/Several scientific publications
Business Plan and Technology Roadmap: Technology packages defined as the minimum exploitable unit/Technology value proposition and commercialisation channels defined/Market potential and dynamics analysis/Identification of market segments identified and go to market strategies
-Technological impacts
Starting from a commercial (Cu/ZnO/Al2O3) catalysts, a new generation of catalysts with increased activity and selectivity, able to deal with impurities in CO2 streams such as the flue gases from a power plant generation were developed. Process integration: extensive work carried out in order to integrate CC with methanol synthesis to optimise energy consumption of the process. Advanced control system developed to provide flexibility to a process that needs to encompass both methanol synthesis with the normal operation of a power generation plant and H2 production using variable renewable generation (strongly dependent on energy prices&grid requirements). Thermo-economic analysis carried including a sensitivity analysis for key variables such as electrolyser CAPEX, electricity price or the price of oxygen obtained as a by-product.
-Economic/Social impacts
Flexible operation of the plant allows to maximise renewable energy use and provide valuable ancillary services. Thus renewable energy curtailment can be minimised and the TSO/DSO may be able to operate the grid more efficiently. Low carbon methanol produced using MefCO2 technology contribute to the decarbonisation of transport as PowerToLiquid technology is an indirect electrification pathway of transport. Direct blending of methanol with gasoline in the EU-28 is currently much lower than the 3% v/v limit set in the FQD directive. Methanol can be used for biodiesel production helping to reduce its CO2 footprint by substituting fossil methanol normally used. DME or MTBE can also be produced from low carbon methanol as well as methanol for bunker fuel or used in Methanol to olefins or methanol to gasoline pathways. Methanol plants using MefCO2 technology can create number of direct jobs comparable to the conventional fossil-based methanol plants. Up to 120 direct jobs could be created for a high capacity plant. Indirect job creation can estimated using a multiple between 5.3-9. Job creation is estimated bw 750 and 1200 jobs per plant.
-Environmental impacts
MefCO2 pilot plant use 1.5t/day CO2 to produce 1t/d of methanol. Scaling up MefCO2 concept can offset significant amounts of CO2 since methanol is one of the most versatile chemicals and its demand is high. MefCO2 most relevant contribution to the descarbonisation of industrial processes and the energy system in the EU is that allows for a more favourable business case for CCS when CCS is coupled with green methanol production. Green methanol can also reduce the fossil fuel consumption. Up to 1 Mtoe/year of gasoline consumption could be reduced if methanol blending reached the 3% limit set in the regulation. Green methanol could not only contribute reaching the 14% target of renewable fuels use in transportation by 2030. MefCO2 concept can also have positive impacts in terms of renewable energy use. Green methanol can act as energy vector storing renewable energy surplus thus contributing to grid stabilisation.
MefCO2 - Logo
MefCO2 process
MefCO2 pilot plant completed
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Moyamoya disease is a rare progressive cerebrovascular disease characterized by bilateral stenosis of vasculature of the Circle of Willis, specifically the distal internal carotid arteries, that leads to extensive collateral circulation. These dilated collateral vessels are described as having a hazy “puff of smoke” appearance on angiography. “Moyamoya” is the Japanese word for this characteristic appearance. The disease was originally described in Japan in 1957 1 and introduced to the English literature in 1969.2 The disease is most known for its distribution in Asian populations, but recently there has been more research and attention given to moyamoya in Europe and North American Moyamoya disease presents clinically due to the ischemic and hemorrhagic complications of abnormal cerebral vascularity.3,4
Moyamoya disease was originally described in Japanese populations but is present in a variety of ethnicities.3,5,6 In Japan, the incidence per 100,000 patient years is between 0.35 to 0.943 with a male: female ratio of 1:1.87. In the US, incidence ranged from 0.05 to 0.17 per 100,000 patient years with a similar gender distribution.3,6 Other population studies have not been as robust but European studies show moyamoya statistics that are more similar to American findings than those of Asian moyamoya findings.4 There is a bimodal distribution of incidence: in early childhood and adulthood, but the doublepeaked incidence is less dramatic in the US and Europe.4,8 Children typically present with the ischemic symptoms and adults can present with either ischemic or hemorrhagic type, with the ischemic type predominating.5,9 Overall, the hemorrhagic type is more common in Asia than the U.S.9 The incidence has been increasing with time, which may be due to increased awareness.5
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The Difference Between Probiotics & Prebiotics
iMiriam2009/iStock/Getty Images
Probiotic and prebiotic foods and supplements enhance the growth of healthy microorganisms in your body. The idea of using bacteria to improve human health has been around since the early 1900s, but the general public did not fully embrace the concept until recently. Today, probiotic and prebiotic products are used widely, most often in the treatment and prevention of gastrointestinal conditions.
Good Bacteria
Your body contains billions of bacteria that help you stay healthy. The largest population of bacteria can be found in your intestines. These beneficial bacteria help you digest food, and without them you could not obtain vitamin K from your food. If the community of bacteria in your intestines is disrupted you may experience digestive difficulties and gastrointestinal symptoms. In order to re-establish healthy intestinal bacteria you can take probiotic or prebiotic supplements.
Probiotics are live microorganisms that can positively impact your health, according to the World Health Organization. Microorganisms are tiny animals made of a single cell. While most probiotics are bacteria, there are also strains of yeast that benefit your body. You can find probiotics in many food products, including fermented dairy and soy products. Probiotics can also be purchased in supplement form. The bacteria and yeast in probiotic products are well-studied strains that have been specially prepared to survive the journey through the stomach into the intestines where they can grow.
Prebiotics are substances that encourage the growth of beneficial bacteria—you can think of prebiotics as food for probiotics and the healthy bacteria in your system. Whereas probiotics are living microorganisms, prebiotics are non-living. Most prebiotics are carbohydrates that the human body cannot digest but which make excellent food sources for beneficial bacteria. Prebiotics can encourage the growth of beneficial bacteria already living in the body and also aid in the growth and maintenance of probiotics.
The combination of probiotic and prebiotic therapies is referred to as synbiotics. The strategy of combining a probiotic with its preferred nutrient may allow for probiotics to stay present in your body for longer, according to a May 1999 article in the "American Journal of Clinical Nutrition." Synbiotic therapies are relatively new and are the focus of many studies to determine their efficacy.
Probiotics and prebiotics have similar health benefits because they both accomplish the goal of increasing the population of healthy bacteria and yeast in your body. Healthy bacteria can form a protective shield in your digestive tract that prevents harmful bacteria and viruses from infecting your body, according to an April 2005 article in "FEMS Microbiology Ecology." The presence of healthy bacteria can also keep your immune system "primed" and ready to respond to a threat. Probiotics and prebiotics are particularly useful in replenishing healthy bacteria communities after a disruption such as an infection or antibiotic use.
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• The solution to Newton's GEXACT VALUE & FORMULA
• Proof of the non-exitence of Dark MatterDOES NOT EXIST
access to the technical calculator
Copper Alloys (physical properties)
Bronze was probably the first successful metal to be widely exploited by mankind, and because tin and copper ores normally occur together (e.g. Cornwall, England), it is most likely that copper was first smelted with tin impurities by accident, thereby initiating the Bronze Age.
Phase diagram for copper-nickel alloy (cupro-nickel)
Fig 1. Copper-Nickel Phase Diagram
Pure copper is a relatively soft (pliable) material with good corrosion resistance, excellent electrical conductivity (>100% IACS) and resistant to low-temperature embrittlement.
However, alloying it with other elements will significantly alter its properties making it suitable
for a much wider range of applications, for example; chromium increases its tensile strength without significantly affecting its electrical conductivity making it ideal for electrical wire.
There are many additional elements (e.g. Zinc, Tin, Nickel, Iron, Aluminium, Lead, Berillium, Cadmium, Silver, Manganese, Magnesium, Cobalt, Silicon, Arsenic, etc.⁽¹⁾) that will improve specific properties for particular applications.
The most obvious alloying element for Copper is Nickel, both of which have very similar atomic physical sizes, i.e.; their relative atomic masses are 58.6934 and 63.546 respectively; their densities are within 0.5% of each other, they both have the same crystal structure (Face-Centre-Cubic) and their atomic radii and electron affinity are within 3% of each other, so they fit together physically remarkably well. As such nickel and copper can be mixed together in any relative percentage from 100% copper to 100% nickel (Fig 1). However, they have significantly different heat and electrical properties, e.g.; melting temperatures, specific heat capacities, thermal and electrical conductivities, etc. so each will change the alloy's thermal and electrical properties according to the relative percentages.
Some of the elements that can be successfully alloyed with Copper to alter its properties in specific ways are listed below:
Common Alloying Elements
Phase diagram for copper-zinc alloy (Brass)
Fig 2. Brass Phase Diagram
Nickel: Nickel and copper can be alloyed in any relative percentage (Fig 1) as both metals are totally soluble within each other at any temperature. Copper-nickel alloys with no added impurities are very tough. The absence of any second-phase in the structure (α, β, γ, etc.) eliminates the possibility of electrolytic corrosion making them very corrosion resistant. Nickel-Silvers are Copper-Nickel alloys with relative percentages; 55%<Cu<63%, 10%<Ni<30%, the remaining percentage of which is zinc, are white in colour and normally used for cutlery and keys as they have the highest corrosion resistance of all the copper alloys. Copper alloys containing nickel have the best high-temperature properties.
Zinc: As can be seen from the phase diagram in Fig 2 copper will support limited levels of zinc at any given temperature before the base metal becomes saturated and no longer behaves like an alloy. Copper alloys containing only zinc are usually called brasses.
0% to 15% zinc leaves brasses ductile but difficult to machine
0% to 20% zinc provides similar corrosion resistance to copper but with higher tensile strength
20% to 40% zinc provides less corrosion resistance than copper and the resultant alloys are subject to dezincification and stress-corrosion cracking.
Phase diagram for copper-tin alloy (Bronze)
Fig 3. Sn-Bronze Phase Diagram
Tin: Tin is added to copper to make traditional bronze (Fig 3). Up to 7% tin may be added to copper for wrought alloys and up to 18% for cast. Because tin normally contains traces of phosphorus these alloys are often called phosphor bronzes (C50500 to C52400) even though there are only trace amounts of phosphor, if any at all, in the alloy. Up to 1% tin is added to brass to improve corrosion resistance (e.g. admiralty and naval brasses). Unlike brass, bronze is not susceptible to stress corrosion cracking. Bronzes with less than 10% tin have excellent elastic properties.
Phase diagram for copper-aluminium alloy (Bronze)
Fig 4. Al-Bronze Phase Diagram
Aluminium: Less than 9.4% aluminium and the alloy will remain ductile (Fig 4). More than this and the alloy will become very hard and brittle if water quenched from above 900°C, but retain very high strength. Aluminium oxide is added to copper to make it very hard indeed. These alloys, normally referred to as aluminium bronze, are characterised by excellent strength and corrosion resistance.
Beryllium: Between 1.75% to 2.5% beryllium (along with 0.5% cobalt) is added to copper in order to allow the base metal to be heat treated (Fig 5). These alloying elements allow the base metal to achieve very high strengths and are normally used for non-sparking tools or springs where its high fatigue resistance can be of considerable benefit.
Chromium: Chromium is added when relatively high strength is required whilst retaining the high electrical conductivity of copper, e.g. in electrical wire (Fig 6).
Lead: Up to 2% lead can be added to any copper alloy in order to improve machinability. However, lead also improves creep and fatigue resistance.
Tellurium: Has a similar effect on copper as lead but you need much less of it to achieve similar levels of creep and fatigue resistance.
Arsenic: Trace amounts of arsenic (<0.05%) is added to Copper-Zinc alloys to improve corrosion resistance and dezincification. This alloying element is usually used in condenser tubes where considerable resistance to corrosion is required.
Silicon: These alloys, normally referred to as silicon bronzes, provide excellent strength and corrosion resistance but they also improve weldability.
Copper Alloys Database – Technical Help
Phase diagram for copper-berilium alloy (Bronze)
Fig 5. Be-Bronze Phase Diagram
The copper alloys database provides only the physical properties of the various copper alloys, for information concerning their applications visit our Uses web page.
The three principle conditions included in the database are wrought (or forged), heat treated and cast. Heat treated is designated with the initials 'HT'.
Whilst the UNS number is included in the Names, it is also provided as a separate category in order to enable you to sort on this value. The UNS category in the database excludes the preceding character 'C'.
All of the Imperial and metric units can be converted using CalQlata's UniQon conversion calculator.
Missing Data
CalQlata has not been able to find verifiable values for the 'coefficient of temperature coefficient of resistance' for 18 of the alloys and one value for 'yield stress'. The database is otherwise complete.
Phase diagram for copper-chromium alloy (Bronze)
Fig 6. Cr-Bronze Phase Diagram
The information provided in this database is as accurate as that available from the USA and European copper authorities. All calculated data (bulk and rigidity moduli) are as accurate as the Poisson's ratio for the various alloys, which are according to various recognised copper authorities.
Melting temperatures are for the lower limit of the solid+liquid region of the phase diagram(s) and have been interpolated between phase diagrams with more than one principle alloying element. The result from this interpolation have been compared with known values and found to be within 2% of the printed data.
Specific heat and thermal conductivity have also been calculated using known formulas and information and found to be within 4.5% of printed data in which CalQlata has found conflicting information.
CalQlata are therefore confident that, until proven otherwise, that the property data included in this database is between 95.5% and 100% accurate.
1. See CalQlata's Elements and Metals databases for the properties of the base metal and its alloying elements
Further Reading
You will find further reading on this subject in reference publications(2, 3 & 44)
Go to the calculator
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Falun Dafa Minghui.org www.minghui.org PRINT
Mysterious Prehistoric Artifacts (Photos)
February 08, 2007 |
(Clearwisdom.net) Modern scientists and archaeologists have found many inexplicable ancient artifacts. They appear to be the remnants of advanced civilizations and have been found throughout the world. These surviving traces of ancient cultures have been found above and underground, in mountain caves, and even on the bottoms of the oceans. These archaeological findings most likely tell us that before the emergence of human civilization, there existed other intelligent beings who built highly developed civilizations that were destroyed for inexplicable reasons.
According to textbooks, human beings have a history of no more than ten thousand years. How do we explain the ancient relics and metal products that can be dated back to many more than ten thousand years?
ST Santiago stone
Soldiers riding on a large dinosaur (Photo: Courtesy Don Patton)
ST Santiago Stone
ICA Stones (Photo: Courtesy Dr. Don Patton)
In the Nazca Plain in the northern part of Peru, there is a stone museum in a small village called Ica (ICA). The museum displays 10,000 pieces of stones engraved with mysterious patterns. They are called ICA stones. The patterns on the stones have been divided into different categories, such as the space galaxies, ancient animals, prehistoric continents, and ancient catastrophes. These classifications are totally out of touch with modern science. It is as if these discoveries challenge our historical texts.
Near the cave where the carved stones were found, there were also fossils millions of years old. The carvings are incredible. They depict men and dinosaurs coexisting, and it has been suggested that the ratio of men and dinosaurs was about the same as human beings and livestock. In other words, dinosaurs appear to have been kept as livestock or were tamed by human beings.
In addition, pictures on the stones depict organ transplants, blood transfusions, telescopes, medical equipment, men chasing dinosaurs, and much more. These scenes are hard to explain with modern science.
From the stone patterns and carvings, we can tell that there was a prehistoric human civilization that had reached a very advanced technology.
Antikythera Device from Greece
On October 17, 2005, during the 2nd International Conference on Ancient Technology, this display showed "Antigone Jisela computer" imitations. (Photo by LOUISA GOULIAMAKI/AFP/Getty Images)
A century ago, a computer called the Antikythera Mechanism was discovered in a sunken shipwreck along the Greek coast. Its bronze high gear and turnable disc are so complex that it cannot be replicated even today, and no one can figure out how it functions.
Recently, scientists from the United Kingdom, Greece, and the United States used high-definition x-ray tomography to look at one of its models. Scientists made a further analysis: the Antikythera Mechanism can add, subtract, multiply, compute, and explain astrophysics, with regard to the moon and positions of planets. It has a calibration disc and may be able to predict solar or lunar eclipses.
Today we understand that the Antikythera Mechanism was used in the second century B.C. Allegedly, this was the very first calculator in history.
South African Metal Balls
Hundreds of metal balls with grooves were found at on a hillside near a lake in South Africa. They have a history of 2.8 billion years. (Photo: Rolfe Marx)
More than ten years ago, miners in South Africa dug up some metal balls in the vicinity where Transvaal Ottosdal pyrophyllite ore is found. These metal balls are about one inch in diameter; some of them are engraved with three circular grooves in the middle of the balls. It appears that these balls are from the Precambrian geological age, which was 2.8 billion years ago.
The grooves on these metal balls are almost intact, even after billions of years. Some believe that they are relics from a prehistoric civilization. We ask ourselves, "Who made these metal balls, and for what purposes were they made?" They have yet to be studied by experts and scholars.
Ancient Model Airplanes
Models of aircraft from murals in the Egyptian ruins of the Temple of Abydos (Photo from internet)
In 1879, British archaeologists found murals in the Abydos Temple, located near Egypt's Cordovez, a barren desert. The murals depict a few objects that look like today's aircraft and a series of similar flying objects, including a helicopter, a submarine or a spacecraft, and even a "UFO." These carvings have a history of three thousand years.
Mankind's first aircraft was manufactured in 1903, but strangely enough, on the ancient Egyptian murals, models of aircraft appeared as early as three thousand years ago.
In 1898, someone found a very similar model of an aircraft in a four-thousand-year-old Egyptian tomb. It was made of wood from small fig trees that grew in the area at that time. That model is stored in the Museum of Antiquities in Cairo.
In 1969, anthropologist Dr. Carryl Mishaboshi found ancient artifacts in the museum's warehouse. They were models of "birds." Each bird is half-man and half-bird with bird feet. These models have their wings spread out, a supine body, a vertical tail, and the marking of a falling, horizontal tail. They look very much like the single-wing aircraft of today.
A golden airplane model found in South America looks similar to modern B52 bombers (Photo from internet)
Even more incredible is that airplane models, looking very similar to the Egyptian airplanes, were found in South America. In one South American country, a golden ancient airplane model that looks very similar to a B52 bomber was unearthed. According to the scientists, this model not only has a sophisticated design but can also fly.
Baghdad, Iraq, Battery
Baghdad, Iraq, third century BC batteries. (Photo from internet)
In June 1936, a group of construction workers accidentally found an ancient grave outside the Iraqi capital of Baghdad. After more than two months of excavation, archaeologists discovered many artifacts from the Persian Dynasty, from 248 BC to 226 BC.
After looking at one item closely, German archaeologist William Carvedilol, executive director of the then Iraqi Museum, made a surprising announcement. He said that a peculiar ancient, earthenware vase about five inches tall was an ancient chemical battery. If one added an acid or alkali solution, it could be used.
Carvedilol's conclusion shocked the archaeologists, and it means that as early as the third century BC the Persians living in the region already had batteries. It is two thousand years earlier than the first battery invented by the physicist Alessandro Volta in 1800.
US Coso Artifacts
Coso man-made materials (Photo from internet)
In February 1961, the residents of Coso Mountain, Olancha, California, discovered an extremely hard piece of quartz at an altitude of more than 400 feet, 40 feet higher than the Owens' riverbed.
The cut surfaces of the quartz remind one of the remnants of certain mechanical devices. Their structures display the extreme complexity of man-made materials. What is more remarkable is that the quartz can be traced back 500,000 years.
The Coso quartz has been dubbbed the "Coso Artifact" and the mysterious substance is known as the spark plug of an internal combustion engine.
Giant Stone Ball from Costa Rica
Giant stone ball from Costa Rica
Around the year 1930, the American George Jitan found about 200 artificial stone balls in the tropical jungle, valleys, and the slopes of the delta of Costa Rica. These stone balls vary in size. They have a diameter of two to 12 feet. They are the products of superb technology and artistry
These mysterious stone balls attracted a great deal of interest. Scientists discovered, after measuring the balls, that they are made of solid granite. The curvature on the surface is almost exactly the same from many different points. The error of the diameter is so minute that it is practically a perfectly "round" ball.
Archaeologists have said that the makers of these balls must have possessed considerable knowledge and superb carving skills. In addition, they must have had very sturdy tools and precision measuring devices, otherwise these products could not have been manufactured.
Who made these giant stone balls, and with what kind of tools, and for what purpose were they made? These questions remain unanswered. Some people call these giant stone balls, "The giant's marbles."
Fossils with Impossible Footprint
William J. Miester, an amateur fossil expert, found a shoe print on a trilobite, dating back to between 200 million and six million years ago. The picture was taken in Utah in 1968. (Photo: Henry Johnson)
Trilobites can be seen on the upper left corner (Photo: Creation Evidence Museum)
In 1938, Dr. Bailey, the head of a geological institute in Kentucky, found 10 identical human footprints in the carboniferous sandstones. Microscopic photos and infrared photographs show that these footprints were caused by the pressure from human feet rather than artificial carving. It is estimated that the rocks with these footprints are about 250 million years old.
Before 1938, two human footprints were discovered on a rock in St. Louis on the Mississippi River's west bank. According to geologists, that rock is about 270 million years old.
Trilobites are small, marine invertebrates that existed on the earth from 600 million years ago to 280 million years ago, when they became extinct. Amateur fossil expert William J. Meister discovered a few fossils from the Precambrian age at Antelope Springs, Utah, in June, 1968. One of the fossils has shoe prints of an adult and a child.
The renowned chemist Melvin A. Cook from Utah University has dated it and said that they are indeed human footprints.
In July, 1968, a well-known geologist, Dr. Bodike, personally went to Antelope Springs and discovered the footprint of a child. In August, 1968, a public school special-education worker from Salt Lake City found two human shoe prints on the same piece of rock containing trilobites fossil. All of these discoveries and their dating by scholars have eliminated any doubts about their existence. They present a serious challenge to traditional geology.
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Escaping a despot, to a brutal frontier.
Men wage war on the surface.
The Dwarves greed has turned underground tombs into fortresses where they practice their art of runes upon their ancestors, fleshcrafting the dead.
Elves, callous and capricious are all beset with madness.
Halflings and half-men and their many rows of teeth, prey upon the moral failings of men.
Main WIki Page
The Shadow of a Dream
nexusphere wheelerjamesr jason_workman_77 Kiera_Moon AmandaHarlan
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CRIM 500 Criminological Theory and Crime Policy (3 Semester Hours)
An in-depth examination of the relationship between criminological theory and crime policy and criminal justice programs. After briefly reviewing early work of Shaw and McKay and delinquency prevention programs based on their work, the course focuses on contemporary crime and public policy practices currently in operation which are grounded in criminological theory.
CRIM 505 Correctional Philosophies (3 Semester Hours)
A detailed discussion of philosophical and behavioral science insights into the nature and goals of punishment as a response to crime. The effectiveness of various types of criminal sanctions at deterring future offending. Included are discussion, of, incapacitation, reformation and rehabilitation.
CRIM 510 Supreme Court Rulings and Criminal Justice (3 Semester Hours)
Every criminal justice practice from arrest through parole is governed by Constitutional provisions and Supreme Court rulings. This course reviews major Supreme Court rulings governing arrest, trial and prisoner’s rights. Special emphasis is on rulings related to diversity, such as racial profiling and sentence disparities.
CRIM 515 Public Order Crime (3 Semester Hours)
An examination of the nature and prevalence of public order offenses. The course addresses their handling by the criminal justice system and public concerns. Emphasis is on community image, fear of crime and safe streets.
CRIM 520 Social Class and Crime (3 Semester Hours)
This course provides students with a comprehensive understanding of the effect of social class on decision making throughout the criminal justice system. Topics covered will include: the effect of social class on victimization, white collar versus blue collar crime, the impact of local, state, and federal laws on class groupings, and the impact of social class on sentencing and recidivism.
CRIM 525 Race and Crime (3 Semester Hours)
This course provides students a detailed analysis of the relationship between racial groups and the criminal justice system. Topics covered will include how structural ecology influences crime in racialized communities, the relationship between the criminal justice system and structural racial inequality, the role of cognitive racial framing in the criminal justice system, and mass incarceration.
CRIM 530 The Prison Industrial Complex (3 Semester Hours)
This course introduces and examines the phenomenon known as “The Prison Industrial Complex.” Topics covered are: the history of for-profit prisons, how political narratives influence public opinion of criminals, the major agencies benefiting from mass incarceration, and the influence of mass incarceration on communities and individuals across the race, class, and gender spectrums.
CRIM 550 Criminal Justice Program Assessment (3 Semester Hours)
This course will provide students with a solid grounding in the applied tools for conducting program evaluation. It will include instruction and experience in conducting evaluation research with training in the methods of evaluation for public, private or nonprofit programs and policies.
CRIM 560 Gender and Crime (3 Semester Hours)
This course explores the implications of gender on law, criminal justice practices and programs. The course addresses women as offenders, victims, and criminal justice practitioners.
CRIM 565 Graduate Research Methods (3 Semester Hours)
This course will analyze research strategies in criminology. It will include the analysis of links between theories and methods in social science research. It provides a detailed review of quantitative and qualitative methods, including research design, sampling, measurement, data collection, and ethical concerns. This course is especially recommended for students planning doctoral level studies.
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Schoharie County 1790 UFO Sighting
During a clear summer night in 1790, a settler in Schoharie County, New York saw a bright shining light in the northern sky. He was playing his fiddle while sitting on the porch. At around 9 in the evening, he noticed a bright shining light in the north sky with a great roar. He described that it grew intensely until it became brighter than the noonday sun. The resident explained that the brightness of the light would allow him to pick up pins anywhere around him.
The German colonist stated he observed what looked like a meteor passing west at around 250 yards from him and approximately 65 feet above the ground. He said that the light maintained low altitude on the other side of the hollow. The object moved above the countryside and rose above tall trees with the speed of galloping horse. When the object reached the Owelus Sowless hill (as what Indians called it), it elevated and flew over the hill. The settler stated that this was the time he lost sight of the mysterious object.
He described it as around 300 yards long with snake-like shape, except that the supposed head looked like the root of a tree plucked up by force. He further said that the shape had no neck, and its thickness was like a young bull and tapered off similar to a serpent. He said that it closely resembled a welding hot iron and sparked similar to it.
He noted the intense heat warmed his house, and it left a stench resembled a burning star or sulfur, which lingered for another day.
The witness was part of the first German settlement in the area. He swore out his statement on August 23, 1823 in the town of Carlisle. The story can be found in The Historical and Philosophical Society of the State of New York records.
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Document Type
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Law professors nowadays mention natural law and natural rights on a regular basis, and not just in jurisprudence. Given that the founding generation universally subscribed to the idea of natural rights, this concept regularly makes a prominent appearance in discussions of constitutional law. One simply cannot avoid the concept if one is to explain Justice Samuel Chase's well-known claim in Calder v. Bull that "[t]here are certain vital principles in our free Republican governments, which will determine and over-rule an apparent and flagrant abuse of legislative power .... An ACf of the Legislature (for I cannot call it a law) contrary to the great first principles of the social compact, cannot be considered a rightful exercise of legislative authority." Nor can law professors explain to their students the reference in the Ninth Amendment to the "other" rights "retained by the people" without mentioning "the preexistent rights of nature."
Publication Citation
20 Harv. J.L. & Pub. Pol’y 655-681 (1997)
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Timeline Watch
Breitling AVI 765
Mariner II, the first interplanetary probe, reaches Venus
1962 Breitling AVI ref. 765, 42mm. case. Manual winding movement cal. Venus 178.
In the mid 1950s, Breitling developed a military aviation-spec chronograph the reference 765. It was a large chronograph, with 22mm. size lugs, a rotating 12 hour steel and 41diameter bezel. In the beginning of 1960s, Breitling changed the black sub-dials to white ones. In 1965, the company decided to update the model but maintained the case, dial and hands. The AVI designation was replaced by CP which stands for Co-Pilot. Then, the material of the bezel was changed from steel to anodized aluminum, besides, Breitling introduced two different types of bezels: a half black and half white bezel and a full black one.
Breitling modified the movement to a 15 minute counter instead of the 30 minute, the 15 minute counter was done because Aircrews had 15 minutes to get an aircraft ready for takeoff and this allowed them to keep track of those 15 minutes easier than with a 30 minute counter.
Breitling has been a leading innovator in high quality stopwatches and chronographs and helped define how chronographs look and function until today.
Breitling launched the first wrist chronograph with a pusher at 2:00 in 1915, presented the first dual pusher wrist chronograph with pushers at 2:00 and 4:00 in 1933 and was one of the first manufacturers to recognize the need of early aviators for wrist watches incorporating such devices.
In 1942 Breitling introduced the Chronomat, the worlds first Smart Watch, a chronograph with a rotating logarithmic slide rule that allowed complex calculations with the turn of your fingers.
Throughout the 1930s to 50s, Breitling continued creating chronographs with different scales to suit different professions, such as tachymeters for production engineers and drivers, and pulsometers for doctors.
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Loughborough University
Leicestershire, UK
LE11 3TU
+44 (0)1509 263171
Loughborough University
Loughborough University Institutional Repository
Title: High rate deposition processes for thin film CdTe solar cells
Authors: Lisco, Fabiana
Keywords: CdS and CdTe thin films
Chemical Bath Deposition (CBD)
Sonochemical bath deposition (sono-CBD)
Pulsed DC magnetron sputtering (PDCMS)
Electrodeposition (ED)
Issue Date: 2015
Publisher: © Lisco, Fabiana
Abstract: This thesis describes the development of a fast rate method for the deposition of high quality CdS and CdTe thin films. The technique uses Pulsed DC Magnetron Sputtering (PDCMS). Surprisingly, the technique produces highly stable process conditions. CREST is the first laboratory worldwide to show that pulsed DC power may be used to deposit CdS and CdTe thin films. This is a very promising process technology with potential for eventual industrial deployment. The major advantage is that the process produces high deposition rates suitable for use in solar module manufacturing. These rates are over an order of magnitude faster than those obtained by RF sputtering. In common with other applications it has also been found that the energetics of the pulsed DC process produce excellent thin film properties and the power supply configuration avoids the need for complex matching circuits. Conventional deposition methodologies for CdS, Chemical Bath Deposition (CBD) and CdTe thin films, Electrodeposition (ED), have been chosen as baselines to compare film properties with Pulsed DC Magnetron Sputtering (PDCMS). One of the issues encountered with the deposition of CdS thin films (window layers) was the presence of pinholes. A Plasma cleaning process of FTO-coated glass prior to the deposition of the CdS/CdTe solar cell has been developed. It strongly modifies and activates the TCO surface, and improves the density and compactness of the deposited CdS thin film. This, in turn, improves the optical and morphological properties of the deposited CdS thin films, resulting in a higher refractive index. The pinhole removal and the increased density allows the use of a much thinner CdS layer, and this reduces absorption of blue spectrum photons and thereby increases the photocurrent and the efficiency of the thin film CdTe cell. Replacing the conventional magnetic stirrer with an ultrasonic probe in the chemical bath (sonoCBD) was found to result in CdS films with higher optical density, higher refractive index, pinhole and void-free, more compact and uniform along the surface and through the thickness of the deposited material. PDCMS at 150 kHz, 500 W, 2.5 μs, 2 s, results in a highly stable process with no plasma arcing. It allows close control of film thickness using time only. The CdS films exhibited a high level of texture in the <001> direction. The grain size was typically ~50 nm. Pinholes and voids could be avoided by reducing the working gas pressure using gas flows ii below 20 sccm. The deposition rate was measured to be 1.33 nm/s on a rotating substrate holder. The equivalent deposition rate for a static substrate is 8.66 nm/s, which is high and much faster than can be achieved using a chemical bath deposition or RF magnetron sputtering. The transmission of CdS can be improved by engineering the band gap of the CdS layer. It has been shown that by adding oxygen to the working gas pressure in an RF sputtering deposition process it is possible to deposit an oxygenated CdS (CdS:O) layer with an improved band gap. In this thesis, oxygenated CdS films for CdTe TF-PV applications have been successfully deposited by using pulsed DC magnetron sputtering. The process is highly stable using a pulse frequency of 150 kHz and a 2.5 μs pulse reverse time. No plasma arcing was detected. A range of CdS:O films were deposited by using O2 flows from 1 sccm to 10 sccm during the deposition process. The deposition rates achieved using pulsed DC magnetron sputtering with only 500 W of power to the magnetron target were in the range ~1.49 nm/s ~2.44 nm/s, depending on the oxygen flow rate used. The properties of CdS thin films deposited by pulsed DC magnetron sputtering and chemical bath deposition have been studied and compared. The pulsed DC magnetron sputtering process produced CdS thin films with the preferred hexagonal <001> oriented crystalline structure with a columnar grain growth, while sonoCBD deposited films were polycrystalline with a cubic structure and small grainy crystallites throughout the thickness of the films. Examination of the PDCMS deposited CdS films confirmed the increased grain size, increased density, and higher crystallinity compared to the sonoCBD CdS films. The deposition rate for CdS obtained using pulsed DC magnetron sputtering was 2.86 nm/s using only 500 W power on a six inch circular target compared to the much slower (0.027 nm/s) for the sonoChemical bath deposited layers. CdTe thin films were grown on CdS films prepared by sonoCBD and Pulsed DC magnetron sputtering. The results showed that the deposition technique used for the CdS layer affected the growth and properties of the CdTe film and also determined the deposition rate of CdTe, being 3 times faster on the sputtered CdS. PDCMS CdTe layers were deposited at ambient temperature, 500 W, 2.9 μs, 10 s, 150 kHz, with a thickness of approximately 2 μm on CdS/TEC10 coated glass. The layers appear iii uniform and smooth with a grain size less than 100 nm, highly compact with the morphology dominated by columnar grain growth. Stress analysis was performed on the CdTe layers deposited at room temperature using different gas flows. Magnetron sputtered thin films deposited under low gas pressure are often subject to compressive stress due to the high mobility of the atoms during the deposition process. A possible way to reduce the stress in the film is the post-deposition annealing treatment. As the lattice parameter increased; the stress in the film is relieved. Also, a changing the deposition substrate temperature had an effect on the microstructure of CdTe thin films. Increasing the deposition temperature increased the grain size, up to ~600 nm. CdTe thin films with low stress have been deposited on CdS/TEC10 coated glass by setting the deposition substrate temperature at ~200°C and using high argon flows ~ 70 sccm Ar. Finally, broadband multilayer ARCs using alternate high and low refractive index dielectric thin films have been developed to improve the light transmission into solar cell devices by reducing the reflection of the glass in the extended wavelength range utilised by thin-film CdTe devices. A four-layer multilayer stack has been designed and tested, which operates across the wavelength range used by thin-film CdTe PV devices (400 850 nm). Optical modelling predicts that the MAR coating reduces the WAR (400-850 nm) from the glass surface from 4.22% down to 1.22%. The application of the MAR coating on a thin-film CdTe solar cell increased the efficiency from 10.55% to 10.93% or by 0.38% in absolute terms. This is a useful 3.6% relative increase in efficiency. The increased light transmission leads to improvement of the short-circuit current density produced by the cell by 0.65 mA/cm2. The MAR sputtering process developed in this work is capable of scaling to an industrial level.
Sponsor: EPSRC
URI: https://dspace.lboro.ac.uk/2134/17965
Appears in Collections:PhD Theses (Mechanical, Electrical and Manufacturing Engineering)
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Which was discovered first: A) Pluto b) Oxygen c) Vitamin C?
Notre-Dame Cathedral in Paris is an example of what type of architecture that uses ribbed vaults and flying buttresses?
Which two animals are said to represent optimists and pessimists in the stock market?
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Novels of which genre are awarded with a Hugo?
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Liberia, Myamnar and the US are the only 3 countries in the world to have not adopted what?
In which Buenos Aires barrio would you find the stadium of the All Boys football team?
The words robot, pistol and dollar are all taken from which Eastern European language?
The flag of which South American country features 27 stars in 9 different constellations?
Which rock band has released albums called Californication, Mothers Milk and Blood Sugar Sex Magik?
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Which Stanley Kubrick film was banned in the UK on its release in 1972 and remained unscreened until 1999?
Who sang the theme to the most recent Bond film, Skyfall?
Name the robot in Futurama.
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In the movie Meet the Parents, Ben Stiller’s character is called Gaylord what?
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Santiago de Compostela is the capital of which autonomous region in Spain?
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Round3 – Women of fiction
What classic novel was written because the author and her friends made a bet about who could write the scariest story?
Branwell was the only brother of which literary sisters?
Swedish author Astrid Lindgren created which children’s book heroine?
Irene Adler is a recurring character in which series of classic detective stories?
Nobel prizewinning poet Gabriela Mistral is from which South American country?
Which book by Alice Walker begins with the line, “You better not never tell nobody but God.”?
Writer George Sand was from which country?
Which author did Nicole Kidman portray in the film The Hours?
Who wrote the Hunger Games trilogy of books?
Which fictional diary writer first appeared in a newspaper column in 1995 and has featured in 2 novels and films?
In 2012 Forbes magazine ranked the richest fictional characters. Put these three characters in order, from poorest to richest: Tywin Lannister, Monty Burns, and Tony Stark
Steven Tyler is the lead singer of which rock group?
In which year was the Cuban Missile Crisis?
List the 4 Tennis Grand Slam events in chronological order throughout the year.
Which African river is the 2nd largest in the world by volume and is also the deepest?
With how many other provinces does Santa Fe share borders?
Which of the lines of Tropic runs through the Northern Hemisphere – Cancer or Capricorn?
Which number comes next in the following sequence? 5, 7, 12, 19, 31, 50, ?
To within one year, in which year was Nelson Mandela born?
The names of only 2 Major League Baseball teams do not end with the letter S – name either of them.
Bull & Bear
Sound of Music
Science Fiction
Charlie & the Chocolate Factory
Metric System
Red Hot Chile Peppers
Clockwork Orange
Whale Shark
John Denver
Robert Zimmerman
John Travolta
John Lennon
Jesse Owens
Pippi Longstocking
Sherlock Holmes
The Colour Purple
French (Amantine Lucile Aurore Dupin)
Virginia Woolf
Suzanne Collins
Bridget Jones
Monty (13), Tywin (12), Tony Stark (5)
Australia (Jan), French (May/June), Wimbledon (June), US (Aug/Sep)
Congo / Zaire
6 – Buenos Aires, Entre Rios, Corrientes, Chaco, Stgo del Est, Cordoba
Boston Red Sox / Chicago White Sox
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A snapshot of bacterial signalling
Bacteria sense external events and send signals to the cell interior via two-component systems formed by a membrane protein, histidine kinase, that has extracellular and intracytoplasmic domains and a soluble intracellular response regulator. The crystal structure of such a system from Thermotoga maritima provides the paradigm for a structural understanding of signalling in bacteria and for its perturbation using structure-based inhibitors. An additional highlight of this study is the demonstration that the histidine kinase component can autophosphorylate in cis geometry, refuting the belief that trans autophosphorylation is universal for histidine kinases.
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An adaptive response to environmental stimuli is essential for life. The most widespread response mechanism involves the transfer of a phosphoryl group amongst the proteins in a signalling process. Two-component signal transduction systems are the chief signalling devices in bacteria and archaea. Actually, they are found in all life domains, although not in animals. A single bacteria can contain tens to hundreds of two-component systems controlling vital processes such as metabolism, development, motility, response to stress or virulence. These systems offer enormous possibilities for the development of new antimicrobials because they play a paramount role in bacterial physiology and in virulence processes, allowing adaptation of a parasite to its human host, or even triggering resistance to known antibiotics.
Although there are numerous variations in the details, two components systems obey the same basic pattern. The prototype consists of two proteins. One of them is a homodimeric membrane sensor called histidine kinase which has one histidine residue in its intracellular part that is autophosphorylated in response to the stimulus (which is sensed by the histidine kinase extracellular domain). The other protein, called the response regulator, is in the cytoplasm, and interacts with the histidine kinase, accepting the phosphate and flying to the chromosome to influence the expression of certain genes. In some cases the targets are not genes but other proteins. The signal decays with dephosphorylation of the response regulator, which is accelerated by interaction with the cognate histidine kinase.
Despite the similarity of the different pairs of two-component systems, there is exquisite partner specificity within each pair, so that there is generally no cross-signalling between different couples. Until now, the structural basis for this selectivity remained a mystery. Since the two components have to associate for both phosphorylation and dephosphorylation of the response regulator but the conditions triggering one or the other activity differ, there should be different modes of mutual recognition associated with these two activities. Another question requiring structural clarification was how the signal triggers autophosphorylation of the histidine kinase. Furthermore, this process was believed to occur in trans, that is, one subunit of the dimer phosphorylating the other subunit, but the structural foundations for trans-autophosphorylation remained unclear. Finally, the chemical mechanisms of the three phosphoryl transfer processes catalysed by each system -autophosphorylation, phosphorylation and dephosphorylation of the response regulator- were mainly conjectural.
Spanish scientists from the Instituto de Biomedicina de Valencia-CSIC (Spain) have provided responses to most of these questions and have shattered the view that autophosphorylation of the histidine kinase component occurs exclusively in trans geometry. They have determined the crystal structure of the complex formed by the intracellular part of a histidine kinase of the bacteria Thermotoga maritima and its cognate response regulator, using beamlines BM16, BM30A and ID14-3. Figure 1 presents a view of the dimeric histidine kinase and response regulator complex. The structure mimics the histidine kinase-catalysed dephosphorylation of the response regulator, but it also sheds light on phosphotransfer to the response regulator. The structure suggests cis rather than trans-phosphorylation of the histidine kinase component, and, in fact, the group proves biochemically that this is actually the case, also proving cis-autophosphorylation in another two-component system from Staphylococcus aureus. The structure allows a mechanism to be proposed for histidine kinase mediated-signalling from the cell exterior to the intracellular part of the histidine kinase. The detail provided by this complex, and the mechanistic and specificity-clarifying insight obtained, offers hopes for practical developments based on this structure.
Structure of the dimeric histidine kinase in complex with its cognate response regulator.
Figure 1. Structure of the dimeric histidine kinase (dimers coloured in light and dark pink, shown as cartoons inside of their semi-transparent surfaces) in complex with its cognate response regulator (green and lime cartoons) viewed from the cell membrane. The phosphoacceptor histidine (light blue) and aspartate (yellow) residues and the sulphate (black) mimicking the phosphoryl group trapped between them are represented in stick representation. The nucleotide (dark blue) bound to the histidine kinase (notice the close proximity with the histidine of the same subunit) is also shown in stick representation.
Principal publication and authors
P. Casino (a,b), V. Rubio (a,b) and A. Marina (a,b), Structural insight into partner specificity and phosphoryl transfer in two-component signal transduction, Cell 139, 325-336 (2009).
(a) Instituto de Biomedicina de Valencia-Consejo Superior de Investigaciones Científicas (IBV-CSIC), Valencia (Spain)
(b) Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) (Spain)
Top image: Detailed view of the active site of the bacterial signalling complex to highlight the involvement of the protein components; histidine kinase in pink and its response regulator in green.
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[Open access]
[Contents scheme]
Acta Cryst. (2012). E68, m1537
[ doi:10.1107/S1600536812045072 ]
Tetrakis(triphenylarsane-[kappa]As)silver(I) trifluoroacetate hemihydrate methanol hemisolvate
S. W. Ng
Abstract: The AgI atom in the title hydrated solvated salt, [Ag(C18H15As)4](CF3CO2)·0.5CH3OH·0.5H2O, is coordinated by four As atoms from triphenylarsane ligands in a distorted tetrahedral geometry. In the crystal, O-H...O hydrogen bonding occurs between carboxylate groups of anions and lattice solvent molecules. Of the four triphenylarsane ligands in the Ag complex cation, two each have an equally disordered phenyl ring while the trifluoroacetate anion is disordered over two positions with respect to the lattice methanol and water molecules which both show half-occupyncy. The crystal studied was a non-merohedral twin with a 13.6 (1)% contribution of the minor twin component.
Copyright © International Union of Crystallography
IUCr Webmaster
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John F. Kennedy
To the Presidency
The Star Senator
JFK's Presidency I
After the 1956 election, many commentators began to speculate about the possibility of JFK making a run for the White House. He did nothing to dampen this buzz, and began laying the groundwork for a presidential bid by accepting frequent speaking engagements around the country. Nor did it hurt that his book, Profiles in Courage, was awarded the prestigious Pulitzer Prize for biography in 1957. That JFK's well-written, but hardly spectacular, work captured the Pulitzer was a surprise, and many have attributed his receipt of the award to the behind-the-scenes machinations of his father's associates. Regardless, winning the Pulitzer gave the handsome, popular senator yet another upward boost, and no one outside the Kennedy inner circle knew that JFK had not actually written it.
In the Senate, meanwhile, JFK walked a tightrope between the Democratic Party's competing interest groups–the liberal wing, which loved Adlai Stevenson but mistrusted the less ideological JFK, and the southern wing, which was conservative and bitterly opposed to the ongoing Civil Rights Movement. In 1957, JFK was given membership on the powerful Senate Committee on Foreign Relations. There, he muted the strident anti-Communism he had displayed during the McCarthy era, in favor of an emphasis on economic aid to the Third World. Additionally, he denounced France's ongoing effort to hold onto its colony in Algeria, a stance that endeared him to liberals. On civil rights issues, meanwhile, JFK tried to placate Southern Democrats by hewing to a middle ground, supporting some civil rights measures while opposing others. This was a pragmatic plan of action, perhaps, since JFK needed to broaden his base of support beyond Catholics and northeasterners. Many blacks, however, came to regard him with suspicion, as a result of this unwillingness to commit to a full civil rights agenda.
After a tragic miscarriage following the 1956 convention, meanwhile, Jackie Kennedy gave birth to her first child, Caroline Bouvier Kennedy, on November 27, 1957. The Kennedy marriage was difficult–JFK was frequently away from home for long stretches (he was vacationing in Europe while Jackie endured her miscarriage), and his penchant for womanizing had continued even after their wedding. It was an era in which the press kept matters of sexual indiscretion tightly under wraps, and the public never knew about JFK's multiple affairs, which only increased as his fame and prestige grew. But Jackie almost certainly knew, and it placed a strain on her union with her husband.
In November 1958, JFK won reelection to the Senate by a huge margin, capturing seventy percent of the vote. Buoyed by this victory and by his increasing visibility, he became a clear front-runner for the Democratic nomination in 1960. Still, the issue of his Catholicism stirred controversy in late 1950s America, and JFK made a number of speeches in which he asserted that his faith would have no impact on his handling of the presidency–that he would make sure that church and state remained safely separate. His promises, and the growing tolerance of religion in America, had their effect, and he swept through the Democratic primaries in 1960, handily defeating his principle adversary, Minnesota Senator Hubert H. Humphrey, Jr. In that era, however, a victory in the primaries did not guarantee a candidate the nomination, and JFK needed every ounce of political muscle to defeat the still-popular Stevenson and Senate Majority Leader Lyndon Baines Johnson at the Democratic Convention. Having won the nomination, JFK made an unlikely but crucial alliance–he tapped the conservative southerner Johnson as his running mate. America was on the edge of a "New Frontier," JFK told the convention, a phrase that was to resonate throughout the campaign.
The Cold War was a dominant issue during the campaign for the presidency. JFK accused the Republicans of having allowed a "missile gap" to grow between the United States and the U.S.S.R., warning that the Soviets had pulled ahead in the nuclear arms race. Feeding his argument was the fact that with their launch of Sputnik in 1957, the Russians had sent a satellite into orbit long before the Americans managed to do so (the U.S. launched its first satellite, Explorer-I, in 1958). The launch of Sputnik had instilled in many people a fear that the United States was losing the struggle against Communism, and JFK played on those fears. Still, the election was remarkably tight–one of the closest in U.S. history–and little details helped decide the matter. During the presidential debate–the first ever televised– JFK appeared virile and commanding, whereas Nixon looked haggard and unshaven. Also critical was JFK's sympathetic phone call to the wife of Martin Luther King, Jr., the civil rights leader, while King was in jail for civil disobedience. The symbolism of the phone call was crucial in helping improve JFK's image in the black community.
In the end, JFK and Johnson won by fewer than a hundred thousand votes. They captured 303 electoral votes to 219 for Nixon, with the difference coming in the populous states of Illinois and Texas (Johnson's home state), where there were widespread allegations of voter fraud on behalf of the Democratic team. But the results were ultimately ratified, and John F. Kennedy officially became the President-elect of the United States. A few weeks after the election, more good news came with the birth of his son, John F. Kennedy, Jr.
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Pollock fishcakes
fish cakes pollack
1. Bring the milk up to a gentle simmer in a wide, heavy-based pan, then lower the fish into the pan.
2. Add some bay leaf and one half of the chilli to the milk and season with sea salt and freshly ground black pepper. Poach the fish for about 6-8 minutes, or until it flakes easily. Remove the pan from the heat and set aside.
3. Put the potato, butter and shallots into a large mixing bowl.
4. Finely chop the remaining half of the chilli and add it to the mix with the shredded green tops of the spring onions.
5. Chop the lemongrass and parsley and add to the mix.
6. Strain the fish (discarding the milk) and flake it into the potato mixture. Stir until combined and season to taste with salt and freshly ground black pepper. Form the mixture into small rounds and put onto a plate.
7. Bake in oven till golden
8. To serve, dress the salad leaves with a little olive oil and balsamic vinegar, season with salt and freshly ground black pepper and serve alongside the fishcakes with a wedge of lemon.
4 way amplifier
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03:17pm Thursday 09 July 2020
Sylvester Researchers Discover Regulating Mechanism of Key Transcription Factor
Sylvester researchers have discovered exactly how one critical regulator affects a transcription factor that is consistently turned on in most cancers. The findings of Edward W. Harhaj, Ph.D., assistant professor of microbiology and immunology and member of the Viral Oncology Program at Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine, and Noula Shembade, Ph.D., research assistant professor of microbiology and immunology, have been published in the February 26 issue of the prestigious journal Science.
Transcription factor nuclear factor kappa-B (NF-ΚB) regulates hundreds of genes that are involved in a wide variety of different functions such as inflammation, cell development and cell death. When NF-ΚB is functioning normally, for instance during an infection, certain cytokines will be produced and they will activate NF-ΚB for a brief period of time. During that time, NF-ΚB activates specific genes and then it’s shut off. If NF-ΚB is not tightly regulated, it stays on continuously which can lead to auto-immune diseases and unregulated cell growth that can become cancer.
The zinc finger protein A20 has an essential role in limiting the strength and duration of NF-ΚB signaling. The process works like an auto-regulatory loop in that NF-ΚB activates, turning on the expression of A20 which in turn shuts down NF-ΚB, resetting the system.
The NF-ΚB pathway is regulated by ubiquitin, a small molecule that attaches itself to proteins and either triggers their degradation or changes how that protein works. Ubiquitination occurs in a 3-step enzymatic cascade consisting of E1, E2 and E3 enzymes. Ubiquitin is first activated by a ubiquitin-activating enzyme (E1) and transferred to a ubiquitin-conjugating enzyme (E2). In the final step, the ubiquitin ligase (E3) transfers ubiquitin to a protein substrate.
There are several important proteins in the NF-ΚB pathway that function as E3s, including TRAF2 and TRAF6. In a normal process, these proteins work by binding to Ubc13 and UbcH5c, both E2 ubiquitin-conjugating enzymes. Harhaj and Shembade discovered that “A20 works by disrupting the interactions between the TRAF proteins and Ubc13 and UbcH5c. It disrupts the binding of E2 to E3 enzymes.”
By shutting down this linear cascade, explains Harhaj, A20 in effect tells NF-ΚB to stop working. In certain cancers such as lymphomas, if A20 is not present, these E3 ligases are persistently turned on leading to constitutive NF-ΚB activation and cell survival. Harhaj explains that this finding could lead scientists to “create drugs that mimic the action of A20, that inhibit E2, E3 interactions when A20 is not expressed.”
Joseph Rosenblatt, M.D., professor of medicine, microbiology and immunology and interim director of Sylvester, says Harhaj’s discovery “provides us with unique insight into the regulation of the NF-ΚB pathway. His research will lead to new discoveries that can be applied to develop new therapies for our patients.”
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As much as I'd like to say that the zombie phenomenon is played out, I can't help but admire the occasional slice of badassery it stirs in the human imagination, such as Shaun of the Dead, "The Walking Dead," World War Z, or this illustration of Velma and Scooby Doo surviving in the zombie apocalypse.
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February 26, 2010
Maintenance and Repair of Condominium Buildings - Who Pays?
Condominiums are divided into units, limited common elements, and common elements. The Washington Condominium Act, which governs condominiums created since July 1, 1990, establishes default rules regarding boundaries and upkeep. These rules have been incorporated into many past and present condominium declarations.
The Washington Condominium Act states that (subject to the declaration) the walls, floors, and ceilings are the boundaries of a unit. Items such as wallboard, plaster, tiles, paint, and other materials constituting part of the finished surfaces are part of the unit. Items such as flues, ducts, conduits, and other fixtures that lie partially within a unit are considered limited common elements to the extent that they serve only that unit. Items such as porches, balconies, exterior windows, and exterior doors that are designed to serve a single unit are limited common elements as well. The rest of the condominium is composed of common elements, which often include siding, roofs, and recreational areas.
The Act later describes who is normally responsible for each portion of a condominium. It states that (subject to the declaration and two other exceptions) the association must pay for maintenance, repair, and replacement of the common elements and the limited common elements and the owners must pay for the maintenance, repair, and replacement of their units. The Act allows associations to shift expenses related to limited common elements to the owners if the declarations permit this. The Act also allows associations under its jurisdiction to shift common expenses caused by an owner’s misconduct to that owner.
The default rules discussed above can be altered by condominium declarations, so those documents must be carefully reviewed in each instance to determine liability for repair costs. If the board is uncertain about the proper outcome, it should ask the association’s attorney to issue a legal opinion on the matter.
February 19, 2010
When Homeowners Associations Attack
"HOA Sues Former Board for $70 Million" is a headline that gets your attention. An Illinois homeowners association recently filed such a lawsuit against its former developer-controlled board (among others), claiming that past board members misused common funds and mismanaged the association's financial affairs. One portion of the lawsuit alleges that board members engaged in self-dealing by using their own or related companies to perform work for the association rather than competitively bidding the work. Another portion of the complaint contends that the association has insufficient reserve funds because dues were kept too low. It remains to be seen how this lawsuit will end.
Board members must always remember that they are obligated to exercise reasonable care in making decisions and must never use their positions to obtain personal benefits. Conducting a thorough investigation, complying with the governing documents and applicable state law, and seeking professional advice when appropriate are three ways that board members can ensure that their decisions are beyond reproach. The guiding principle is always the good of the community.
February 12, 2010
Resale Certificates - Provide a Proper Preview
According to the Washington Condominium Act, a prospective purchaser of a condominium unit must receive a resale certificate from the owner of that unit before the sale closes. The condominium association is required to provide the owner with a signed resale certificate within 10 days of each request, and it is allowed to charge a fee of up to $150 for this service. An officer or agent of the association must sign that document based upon actual knowledge.
Resale certificates provide a prospective buyer with a snapshot of the association in general and the unit in particular. If delinquent assessments are owed by the current owner, this must be disclosed. If significant repair work that will cost more than 5% of the annual budget is anticipated, this must be disclosed. If any alteration or improvement of the unit or limited common area violates the declaration, this must be disclosed. A statement of the association’s reserves must be disclosed, along with financial statements, balance sheets, and operating budgets. A reserve study must be provided or a mandatory disclosure about the lack of a reserve study must be given. A copy of the declaration, bylaws, and rules must be provided as well.
One broad entitlement to information in resale certificates is “any other information reasonably requested by mortgagees of prospective purchasers of units.” The Act states that information typically requested by entities like the federal national mortgage association and the department of housing and urban development is discoverable in a resale certificate if it is reasonably available to the association. Fannie Mae and HUD have recently begun requesting more information about condominiums, including owner occupancy rates and delinquency rates, so this information may need to be provided.
Associations should take their legal obligations to prospective purchasers seriously and err on the side of disclosure when completing resale certificates. A useful rule of thumb is: "If I was considering buying this unit, would I want to know about this?" Boards do not want to get involved in lawsuits seeking damages caused by inadequate resale certificates.
February 5, 2010
Census Calls for Cautious Cooperation
Congress is spending $2.5 million this year to advertise the U.S. Census during the Super Bowl. This could result in substantial net savings if the ads (which may reach 45% of all U.S. adults) cause more people to mail back their census forms. Each percentage point increase in the mail response rate prevents an additional $85 million from being spent to find and count those people.
Households are required by law to respond to the Census Bureau’s requests for information, and community associations could face penalties if they unreasonably impede Census work. However, associations and owners should be aware that unscrupulous persons in their area may attempt to falsely pose as Census workers. The Better Business Bureau offers the following useful tips to prevent Census-related fraud:
• If a U.S. Census worker knocks on your door, they will have a badge, a hand-held device, a Census Bureau canvas bag, and a confidentiality notice. Ask to see their identification and their badge before answering their questions.
• Census workers are currently only knocking on doors to verify address information. Do not give your Social Security number, credit card number, or bank account number to anyone, even if they claim they need it for the U.S. Census. While the Census Bureau might ask for basic financial information, such as a salary range, it will not ask for Social Security, bank account, or credit card numbers, nor will employees solicit donations.
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The UESPWiki – Your source for The Elder Scrolls since 1995
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The night sky from Nirn, with Masser and Secunda
Mundus is the plane or realm of existence that encompasses Nirn, its moons, and attendant Aedric planets. For all intents and purposes Mundus refers to these heavenly bodies alone, as they themselves float in Oblivion. Mundus is a collaborative construct created by many divine beings. It was first conceptualized by Lorkhan, who then convinced other et'Ada (except the Padomay-aligned et'Ada, i.e., the Daedra) to assist him in its construction. Of these et'Ada, Magnus became the Architect, who drew up the plans for Mundus.
Some of the et'Ada gave parts of themselves entirely to the creation of Mundus. These became the eight planets of Mundus (not including Nirn); they are also identified as the Eight Divines, or Aedra. Some Aedra gave themselves completely to their creation, and became the Earthbones that form the substance and life of the final planet: Nirn. Soon after the planets had formed, Magnus became disgusted at what Mundus was, and so left for Aetherius, his passage ripping a hole in Oblivion (the realm of Daedra that surrounds Mundus and separates it from Aetherius). This rip is viewed as the sun, and is responsible for much of Mundus' magical energy. Others soon followed after Magnus; these et'Ada left smaller holes, which became the stars. Some et'Ada did not manage to escape or chose to stay on Nirn as spirits. These et'Ada changed into the Earthbones (Ehlnofey) or simply wasted away into nothingness.
Because of Lorkhan's trickery of the other et'Ada, the Aedra met at Direnni Tower (also known as the Adamantine Tower or the Ur-Tower) to discuss the punishment of Lorkhan. Trinimac then ripped the Trickster's heart from his chest, which Auri-El then fired into the sea with his bow.[1] Its impact rent the earth and created a mighty volcano, now known as Red Mountain. The creation of the landmass that is modern Vvardenfell can be traced to this event. Because Lorkhan's Heart remained on Tamriel, it impregnated Nirn with his spirit and "a reasonable amount of his selfishness", while his corpse remained floating above the new planet as the two moons.[2]
[edit] Maps
[edit] Notes
• Mundus is the Latin word for "World" or "Universe".
[edit] References
1. ^ The Monomyth
2. ^ The Lunar LorkhanFal Droon
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In the county of Uasin Gishu, Kenya, a recent article in Ethnobotany Research and Applications, local plants have many uses for fodder, medicine, food, and building material, but today this knowledge is threatened by increased pressures on the land. While the list of plants and their uses provides valuable basic knowledge, the article heightened my interest in a completely different realm of inquiry.
Medicinal plants in particular have very social, dynamic lives, from their administration by healers or healthcare personnel, to the everyday person collecting for personal health needs, to the younger generation or those from industrial centers actively pursuing the reclamation of knowledge. Who are the predominant users of these plants, and who are the administrators? Are there pushes for cultural revitalization, as there are efforts to revitalize perceived losses in knowledge in much of the world? I would be interested to learn the deeper stories of the list of plants.
For example, in Finland, efforts to revitalize traditional knowledge span from rural to urban areas. However, revitalization in rural areas appears to carry more discourses of “traditional” knowledge, while urban areas tend to focus on plants as products, for which remedies become absorbed into field guides devoid of cultural origins in an encyclopedic list. Do similar processes exist in Kenya and Uasin Gishu?
Meanwhile, a similar documentation of plant uses was published in the Journal of Ethnopharmacology. They found that 90 wild species are used in north-eastern Sicily. The group used a cultural importance index to determine which plants were most crucial to local pharmacopeias. It is important to highlight the most ubiquitously used plants, because often it is these plants that carry the most cultural weight. For example, in Finland the clinker polypore has recently enjoyed widespread commercial fame, but the success only rides the tale of a long history. It is these histories that breathe life into plants.
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“Daydreams” by Audien: EP Review
Daydreams is yet another EP that I plucked off spotify at random. What can I say, sometimes a little adventure is exactly what is needed to mix up what you listen to. Featuring artists like Lady Antebellum, Voyageur, and Rumors, the EP seems enticing and makes me intrigued to hear what it hides in it’s quick length.
“Something Better”, which features Lady Antebellum, opens with a melodic, jazzy sound that drops into a gentle flow of vocals. The song pulls the listener in with evocative lyrics that compliment the upbeat mix of sound that the backing music flows through. With stopovers at a heavy electronic influence, the song certainly makes an impression on the listener and makes a great opening to the EP as a whole. “Pharaohs”, featuring Voyageur, starts off with a quieter feeling until the lyrics come in, and bring a more rhythm based feeling to the song. It’s a different sound entirely from “Something Better”, and yet it flows perfectly with the previous track. It captures the mind, and really takes the breath away as it plays. From the first half of the EP alone, Audien seems like an artist that’s more than worth a second listen. “Rooms” begins with a quick paced electronic sound that flows in waves, and gets progressively louder before dropping off to an open and airy sound that creates a more relaxed feeling as it builds. The sound changes dramatically a third time, and yet the song keeps the same upbeat energy throughout its shifts in sound, both subtle and jarring. The silence after it ends leaves the song resonating in the mind, and really leaves the stage open for the final track on the album. “Monaco”, featuring Rumors, wraps up the album with a gentle, vibrating opening, and vocals that easily paint a story in the mind. The vocals and music blend together wonderfully, balanced against each other with ease. The song creates an easy ending to the EP, but the urge to listen to it a second time stays long after the final notes fade.
All in all? This was a great EP and I heartily recommend that you listen to it as soon as you find the time. It’s under twenty minutes, but it makes up for it with music that is positively wonderful on the ears. I’ll definitely be listening to more Audien in the future, and hope that you will be too.
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The Magic Ingredients in Intel's New, Tinier Transistor
Researchers predict the materials Intel and IBM may have chosen to make their just-announced ultrasmall transistors
Intel transistor
Last week Intel and IBM both announced that they had figured out a way to further shrink the size of transistors, the tiny on-off switches that power computers. The trick, according to Intel, is introducing the metal hafnium into the mix—an addition that marks the first major change in transistor materials in four decades. Hafnium-based computer circuits would likely be denser, faster and consume less power than existing microprocessors.
"It's a very, very significant event," says electrical engineer Carlton Osburn of North Carolina State University, member of a research team that studied hafnium and other advanced transistor materials. "This directly addresses one of those grand challenges" in semiconductor manufacturing.
Although the companies have yet to release design details, Osburn and other experts were able to make some informed guesses about their inner workings and the challenges in manufacturing them.
Intel's demonstration consisted of a hafnium-based microprocessor capable of running three different computer operating systems. In its transistors, hafnium oxide plays the role of the so-called gate dielectric, an insulating layer that separates the transistor's electrode from its silicon channel for carrying current. A voltage emanating from the electrode switches the transistor on or off by controlling the flow of electrons across that channel. The key is making the insulator as thin as possible in order to switch the channel faster and pack more transistors onto a chip.
Over the past decade, Intel and other microchip makers had increasingly bumped up against a fundamental problem: electricity would begin leaking from the glasslike silicon dioxide insulating layer as its width shrank to nearly a nanometer. Consequently, the transistors required inordinate amounts of power.
To overcome this obstacle, chipmakers had to determine how to replace silicon dioxide with so-called high-k materials like hafnium and zirconium. A material's performance as a gate dielectric depends on its thickness and its k-value, or dielectric constant, which reflects its ability to store a charge. Because hafnium has a higher k-value than silicon dioxide, it should be able to do the same or better job at a thickness that prevents leakage. That advance would allow Intel to shrink the smallest dimension of its transistors from today's 65 nanometers to a svelte 45 nanometers, keeping the furious pace of transistor miniaturization on its expected track.
The beauty of silicon dioxide was that manufacturers could grow it simply by placing a silicon wafer into a vessel filled with oxygen, Yale University electrical engineer Tso-Ping Ma says. Producing hafnium oxide transistors would require chipmakers to add multiple new steps to the manufacturing process—in part because the electrodes must be fashioned from metal, instead of from a form of silicon, to remain compatible with the hafnium. Initial production costs would probably be higher and early chips likely to contain more defects, Ma says, because the materials would be more sensitive to heat and other influences.
Osburn says that a hafnium transistor would still need a thin layer of silicon dioxide at the bottom of the gate insulator to dissipate excess charges that would otherwise accumulate there and interfere with the device. Ma, who says he has worked with both the Intel and IBM research groups but is not privy to either's design, adds that the presence of silicon dioxide would require chipmakers to add nitrogen to the hafnium oxide as well. Without it, he says, the insulator would only have a modestly improved k-value that would be insufficient for the next two or three reductions in transistor size.
The only scientific question Ma sees is in the metal electrodes. There are actually two varieties of transistors used in computer circuits, and each requires its own type of metal. Ma says that one compound would most likely be a stable material such as titanium nitride or tantalum carbide, but that he does not know what the other metal would be.
Researchers, however, seem to have that under control: The same day that Intel made its announcement, SEMATECH, the semiconductor manufacturers' research consortium, announced that its engineers had tested high-k versions of both transistors.
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John Marwood Cleese is an English actor, voice actor, screenwriter, producer, and comedian, who is well known for his role as Basil Fawlty in Fawlty Towers and his roles in the Monty Python, Harry Potter and Shrek films. He also voiced Cat R. Waul in the 1991 film, An American Tail: Fievel Goes West, as well as the voice of Jean-Bob the frog in the 1994 animated film, The Swan Princess.
He guest-starred in Episode 223 of The Muppet Show, voiced Ape in the George of the Jungle films and narrated Winnie the Pooh and Mickey Mouse Works cartoons, including "A Midsummer Night's Dream", "Around the World in Eighty Days", "The Nutcracker" and "Mickey's Mechanical House." He also played the role of Dr. Julius Plumford in Disney's Rudyard Kipling's The Jungle Book and a grizzled sergeant in Around the World in 80 Days. He voiced Bulldog in the 2013 Disney animated film Planes and Mecury in Valiant.
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Black Barrel Navy Spiced Rum
A.H.Riise’s rums have always been closely connected to the world’s oceans and the seafaring life, and the wonderful-tasting Black Barrel Navy Spiced Rum is no exception.
Several centuries of experience in aging and blending are evident in this spiced rum. Through aging in heavily burnt oak casks the rum gains a character and colour that lives completely up to its name: black as night and spiced according to an ancient secret recipe.
A steadfast companion on shore, at sea and in the air.
Logbook: A.H. Riise, Ærø and Danishness
A.H. Riise grew up on Ærø. His upbringing was one of financial security, and the family did not need to fear hunger, poverty or the epidemics which ravaged Denmark and Europe at that time. A.H. Riise’s lineage was one of solid, Danish family, but with one exception; at that time, Ærø was part of the Duchy of Schlesvig, and Ærø was not incorporated into the kingdom of Denmark until the peace treaty following the 1864 war. There was however always a special bond between the king and all of A.H. Riise’s family, who considered Denmark as their fatherland and the king as their supreme ruler.
Mocha, walnuts, burnt figs and lightly burnt notes of oak
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Emily Woods
Director, Communications
Environment and Climate Change Canada, Government of Canada
Chelsea, Québec
Emily’s career has taken her from coast-to-coast-to-coast, where she has served in the Governments of Alberta, British Columbia, Nunavut and Canada, as well as an Indigenous organization. Drawing on this pan-Canadian experience, Emily works to foster a deeper understanding of the opportunities and challenges of each region to help inform and strengthen government decision-making and communications. Emily currently serves as the Director of Climate Change and International Communications for the Government of Canada. She is passionate about informing and inspiring Canadians and the rest of the world, about our generation’s greatest challenge: climate change. Emily loves being outdoors and can often be found cross-country skiing in Gatineau Park.
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Jul 042011
One of my recent interests has been in solving problems with various kinds of satisfiability solvers. As an introduction to this idea I want to demonstrate how to create a sudoku solver with almost no effort by reduction to a common satisfiability problem (CNF-SAT) and using an existing solver (MiniSat).
Solving sudoku by reduction to CNF-sat is hardly a new idea, I’m sure a quick google would show various approaches. If the mathematical notation below looks a little scary perhaps try reading the code further down, it really is quite simple if you can read propositional formulas.
A quick sudoku recap
A sudoku puzzle is a 9×9 grid of cells, split into 9 non overlapping 3×3 “boxes”. Some of these will be labelled with a digit from 1 to 9, others will be blank. The aim is to label the remaining cells so that every row, column and box contains the digits 1 through 9.
Unsolved sudoku grid
Unsolved sudoku grid
Solved sudoku gird
Solved sudoku gird
Perhaps the most well known satisfiability problem is propositional satisfiability: given a formula in propositional logic can we find assignments for all the variables which makes the formula true? A subset of this problem is satisfiability on formulas in conjunctive normal form (CNF-SAT). A formula is in conjunctive normal form if it is a conjunction of clauses, where a clause is a disjunction of literals (a literal is just a variable or its negation), e.g
\[ (a \vee \neg b) \wedge (\neg a \vee c \vee d) \wedge (\neg b \vee \wedge \neg d) \] \[ a \wedge (\neg a \wedge \neg b) \]
The reduction
Our aim is, given an unsolved sudoku grid, to identify a set of variables and a CNF formula upon them which is satisfiable if and only if the gird has a solution. Additionally we want the assignment of variables (the model) to describe unambiguously the solution to the puzzle. We’ll proceed by first finding a way to represent the grid with boolean variables, then find formulas which ensure the grid satisfies the sudoku constraints and matches the given puzzle grid.
Grid representation
Let us begin by identifying a way to describe sudoku grids with a set of boolean variables which would be easy to enforce sudoku constraints upon with a propositional formula. Let our boolean variables be \( \{x_{i,j,k} : i,j,k \in \{1,\ldots,9\} \}\). The interpretation is that if \( x_{i,j,k} \) is true then cell \( (i,j) \) is labelled with k.
Of course this representation does not enforce that every cell has exactly one label! We’ll have to include a term in the reduction formula that ensures this is the case. If a cell has more than one label than it will have some pair of distinct labels. So given a cell \( (i,j) \) the we can check it has exactly one label with a CNF formula
\[ l_{i,j}:=(x_{i,j,1} \vee \ldots \vee x_{i,j,9}) \bigwedge_{k,l \in \{1,\ldots,9\}}_{k \neq l} \neg x_{i,j,k} \vee \neg x_{i,j,l}.\]
So to ensure the model describes a labelling we just need the formula
\[ \sigma := \bigwedge_{i,j \in \{ 1,\ldots,9 \}} l_{i,j} \] to be true. Note this is in CNF.
Sudoku constraints
Now we need to include the sudoku constraints: each row, column and box needs to contain the labels 1 through 9. Let a group be a set of 9 cells that must contain all the digit. Let \( \mathcal{G} \) be a set of sets containing the all the groups on a sudoku grid, i.e groups for the rows, columns and boxes \(3 \times 3 \) boxes. We can now express the sudoku constraint with the following CNF formula:
\[ \phi = \underbrace{\bigwedge_{k \in \{1,\ldots,9\}}}_{\textrm{for each digit}} \underbrace{\left( \bigvee_{(i,j)\in\mathcal{G}} x_{i,j,k} \right)}_{\textrm{each group has}}_{ \textrm{a cell labeled with it}} \]
Once again this is a CNF.
Puzzle constraints
Now we just need to include constraints that restrict cells that were labelled in the puzzle grid to keep that label. Let
\[ \mathcal{C}:=\{(i,j,k):\textrm{cell $(i,j)$ has label $k$ in puzzle grid}\}. \]
Then the formula
\[ \psi := \bigwedge_{(i,j,k) \in \mathcal{C}}x_{i,j,k}\]
ensures that the solution matches the original puzzle (again \( \psi \) is in CNF).
Putting it all together
So given a puzzle the formula
\[ \sigma \wedge \phi \wedge \psi \] is satisfied if and only if the variables \( \{x_{i,j,k} : i,j,k \in \{1,\ldots,9\} \}\) describe a solution to the puzzle. Cell \( (i,j) \) is labelled \( k \) if and only if \( x_{i,j,k} \) is true.
It’s easy enough to code this up in Haskell. The following code extract constructs the formula form a sudoku grid. A variable in MiniSat is a positive integer, so I had to create a bijection from labelled cells (triples) to integers. A CNF formula in the code below is just a list of list of integers.
-- cartesean product of a list with itself
-- Sudoku cells values are represented by triples where the first and second
-- entry specify row and column respectively (zero indexed) and the third
-- specifies labelling (1-9).
-- Define a bijection between cell value triples and natural numbers that will
-- serve as boolean variable names.
cellToVar (i,j,k) = fromIntegral $ (k-1)*81 + i*9 + j + 1
varToCell x = ((i `mod` 81) `div` 9, i `mod` 9, (i `div` 81)+1)
where i = (fromIntegral x)-1
-- List of clauses that ensures a given cell is labeled with exactly one value.
-- Checks for every pair of labels that the cell is NOT labeled by both
-- and that the cell is is labeled with at least one value.
oneLabel (i,j) = atLeastOne : lessThan2
where notBoth (c1,c2) = [- cellToVar (i,j,c1), - cellToVar (i,j,c2)]
lessThan2 = map notBoth $ [(i,j) | (i,j) <- cross [1..9], i /= j]
atLeastOne = map cellToVar [(i,j,k) | k <- [1..9]]
-- List of clauses that ensures every cell has exactly one label.
validLabeling = foldr ((++).oneLabel) [] $ cross [0..8]
-- Definition: A group of cells is a set of cells that must contain
-- one of all the labels. i.e. One of the column, rows or 3x3 squares.
-- List of the square groups of cells.
squareGroups = [quadrent i j | (i,j) <- cross [0..2]]
where quadrent x y = [(x*3+i,y*3+j) | (i,j) <- cross [0..2]]
-- List of rows, list of cols.
rows = [[(i,j) | i <- [0..8]] | j <- [0..8]]
cols = [[(i,j) | j <- [0..8]] | i <- [0..8]]
-- Formula that ensures a group of cells contains at least one of all labels [1-9].
groupGood group = foldr ((:).label) [] [1..9]
where label k = map cellToVar [(i,j,k) | (i,j) <- group ]
-- Formula ensuring a labeling is good.
-- A labeling is "good" if it satisfies the sudoku constraints, that is every
-- square, row and cell contains one of each label.
goodLabeling = foldr ((++).groupGood) [] (squareGroups ++ rows ++ cols)
-- Produce a formula for a set of sudoku constraints - filled in cells,
-- for which a model describes a sudoku solution.
sudokuForm cells = validLabeling ++ goodLabeling ++ (map consClause cells)
where consClause cell = [cellToVar cell]
To see the full code, which includes IO, have a look at the github.
Results and further thoughts
Considering that we’ve at no point actually thought about how to solve sudokus this technique works remarkably well. This solver can reliably solve “hard” instances quickly, simple naïve solvers can take a long time on these. The github contains some harder puzzles, some coming from this article.
Of course specialist algorithms will do even better, but we’ve pretty much solved the problem with no effort. In a future post I hope to describe some harder problems I’ve tackled with boolean satisfiability, in these cases there were no existing algorithms to solve the problem and SAT (but not CNF-SAT) reduction turned out to be the best of all the techniques I tried!
Posted by at 6:24 pm
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Panna Maria Heritage Center Logo
Silesian Parishes: St. Joseph Cemetery / Inez
Some of the earliest immigrants to Texas from Upper Silesia did not join the main body that settled Panna Maria. Many who had been craftsmen or merchants in Poland, for example, found it more convenient to stay in San Antonio, where they could establish businesses. Others who traveled the rugged road to the interior from the main disembarkation points in Indianola or Galveston decided to halt at some attractive spot along the way, in Victoria County. This was the original location of Espíritu Santo mission, founded in the 1720s (Nuestra Señora del Espíritu Santo de Zúñiga Mission, commonly called La Bahía). The area has seen a settlement called Arenosa, after a nearby creek, and another known as Garcitas (also after a creek). After the Civil War, Silesians founded another colony here, which they called Gazeta. In 1873, they established a small Catholic church and cemetery on one acre of land deeded for that purpose by parishioner Frank Garvel. In 1889, however, to take full advantage of a new railroad, the congregation moved to the town of Inez. They reconstructed their church building, and dedicated it to St. Joseph in 1890. In August 1892, Frank and Anna Obsta Garvel conveyed four acres in Inez for a new cemetery, and reclaimed the land in Gazeta. In 1900, the town boasted various businesses, including a lumberyard, a cotton gin, and a mercantile store. Many of these (and indeed, most of the townsite) were owned by Rancher Henry Clay Koontz Sr., best known as the founder of the Koontz Ranch with its C Bar E brand. The population of Inez is currently less than two thousand residents.
Parish News
Then and Now
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Farmer and bullocks
Farmer and bullocks
E768/0381 Rights Managed
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Caption: Farmer and bullocks. Farmer stands next to two bullocks laden with a plough in a paddy field in Antsirabe, Madagascar. Antsirabe is a rich agricultural area located in the north east of the island.
Keywords: agricultural, agriculture, antsirabe, black, duo, farm, farming, farms, field, human, land use, livestock, madagascar, male, muddy, one, paddie field, paddy field, pair, single, traditional, two, wet
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Sunday, June 3, 2012
Michaels and Unusual No Trump
If there is one bid that is almost universally misunderstood and misused by experienced players, it's the conventional bid that shows two unbid five card suits, represented by Michaels and the Unusual No Trump. Michaels is a cue bid of openers' one level bid to show either both majors if the opening bid is a minor or the other major and an undesignated minor if the opening bid is a major. The Unusual No Trump is a conventional bid of a jump to two no trump over an opening one level bid that shows either both minors or the two lower unbid suits.
The problem arises because these players have heard from some "expert" that some people play these only with "good-bad" hands and with intermediate range hands they bid the two suits individually. There are two problems with this statement.
The first is that the "expert" never defines what a "bad" hand is. They tell you that the intermediate range is probably 10-16 HCP, but don't define a range for the "bad" hand. As a result, the "expert's" trusting acolyte defines bad as anything under 10 HCP.
The second is that it defies reason. Why would you want to force your partner to bid at the three level (in the case of unusual no trump) when you have a weak hand and she might be forced to bid a two card suit (or in rare circumstances a one card suit)?
This happened to me recently in a two table social team game. Here's my hand:
The bidding went:
West North East South (me)
1D 2D 3C Dbl
3D P P Dbl
P P P
I'm salivating. We're going to kill this hand. My partner has the majors and I have the minors. At a minimum, I should get three tricks, two diamonds and a club and my partner should have at least two quick tricks to make her bid. Well, to make a long painful story mercifully short, we were the ones who got killed. My partner had four points, one queen and two jacks, and couldn't take a trick. I got my three tricks, but that meant they made their bid with an overtrick, doubled.
When the round was over, the player at the other table who had my partner's hand, a more experienced player than my partner, said that she bid it the same way. Since her partner was not an expert, the final diamond contract wasn't doubled (one of the reasons experts do well is that they love to double partscores).
The reason they both bid Michaels? Because they had heard that it should be used with "good and bad" hands. Well, they certainly had a "bad" hand. But because the "expert" never defines the "bad" hand, people think that any 13 cards that are 5-5 in shape will suffice.
So, clearly, people don't understand this dichotomy and it's time to explain it. First, it makes no sense to only use it with good or bad hands and to bid intermediate hands by bidding the suit. Second, if you use these conventions, use them all the time in accordance with the following rules:
For Unusual No Trump:
Not Vulnerable: At least 5-5 in your two suits, not less than 9 HCP and two quick tricks in your suits, and if at the bottom of your range, you must have good suits. You may have any upper range of points, but this is the minimum.
Vulnerable: At least 5-5 in your two suits, two quick tricks, and generally, not less than 12 HCP; if both of your suits are good, however, you may do it with 11 HCP.
For Michaels:
Not vulnerable. At least 5-5 in your two suits and 8 HCP with the points all in your suits, if making the bid with the minimum.
Vulnerable. At least 5-5 in your two suits and 10 useful HCP, meaning at least two quick tricks, and they should be in your suits.
Let me explain why discipline is important. First, often when you have a two suited hand, your partner holds the other two suits, so you might find yourself in a defensive position where you can double for penalty, as I was. You must ensure that your partner can trust your bid and vice-versa.
Second, since you are forcing your partner to bid at a higher level with unknown shape and values, you are risking a bad contract that might be doubled, so you must have the values promised above.
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Lifting of the arms and shoulders with Aptos Threads
APTOS thread lift is a minimally invasive procedure performed with threads consisting of poly-L-lactic acid and e-caprolactone. Threads are hypoallergenic and completely biocompatible with the human body. Each year, APTOS extends the range of products and introduces to the market more advanced threads and methods for solving specific problems in certain areas, taking into account the individual features of the structure of the face and body. For example, threads for correction of the inner surface of arms, best solve the problem of sagging skin in this area, with the minimum risk of complications and practically no downtime.
Non-surgical brachioplasty
The main indication for non-surgical brachioplasty - is flabby sagging skin due to sudden weight loss, after childbirth, aging or hormonal changes.
Not long ago, the most popular solution to this problem was a plastic surgery, which, like all surgical interventions, involves a number of risks, such as a long recovery period, general anesthesia, keloid or deep scars.
APTOS Company offers a more gentle method of thread lifting: a minimally invasive procedure performed under local anesthesia with a small punctures so that it does not leave visible scars and does not require long recovery period.
Advantages of Aptos threads:
· safety;
· immediately evident result;
· minimal traumatism;
· the 20-minute procedure;
· minimum of downtime;
· long-term effect;
· no risk of rejection or allergic reactions.
How is lifting of arms performed with Aptos threads?
Consult the patient and exclude any contraindications. Prepare the patient, including marking and cleaning the operation area. Make infiltrative anesthesia.
Procedure: insertion of Excellence Body in subdermal layer following marking lines. Long threads (25 cm) with barbs make 3D-reinforcement of those areas of the body where tissues become weak and prevention of ptosis is necessary.
The result of a thread lift
The result of the procedure can be estimated immediately after its termination. It gradually increases after about two weeks when the swelling totally disappear. It happens due to poly-L-lactic acid and caprolactone. As they dissolve naturally, the skin starts to produce more collagen which improves skin tone, texture, color and hydration.
Besides arms Aptos thread lift can be performed for inner thighs, abdomen, area above knee, breast, and hands. APTOS product line is also represented by a wide range of threads for lifting various areas of the face and neck.
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Detox Auto Ship
From: $69.95 / month
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Glutathione: A tripeptide composted of cysteine, glutamic acid, and glycine is a powerful antioxidant, major free radical scavenger, and known as the master detoxifier in the human body.
In the body, glutathione is important for actual cell detoxification, while other nutrients such as such as chlorella, dandelion greens, garlic, Gotu Kola, and aloe also act as powerful antioxidants and help to detoxify the body in other ways.
Nutrients like milk thistle with 80% Sylamarin and Goji Berry support liver function, an important part of the detoxification process.
Activated charcoal: Trap toxins, binds poisons, and absorbs chemicals to help rid the body of undesirable substances.
Fiber: Once the activated charcoal has captured toxins from the cells, body systems, and environment, it is important to move them out of the body. Fiber from elements such as psyllium husk and nutrients such as Senna leaf, and FDA-approved nonprescription laxative help remove the unwanted materials.
The daily exposure to toxins in virtually every area of life diminishes or “wastes” glutathione, so it is vitally important to take measures to increase it’s level in the cell.
Not well absorbed through normal digestion as straight glutathione, so to enhance levels in the body, you must increase the intake of the nutrients that make it up: cysteine, glutamic acid, and glycine as well as cruciferous vegetables like Broccoli.
There are many important minerals, amino acids, and nutrients known for providing benefits in the blood, promoting gut health, supporting detoxification pathways, enhancing bowel function, and assisting the immune system in dealing with toxins and various unhealthy organisms such as Milk Thistle, chlorella, aloe, garlic, dandelion greens, Goji, and Gotu Kola.
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Crimean Tatars, According to Gustav Radde—Part 1
Nov 1, 2014 by
(The following post deviates from the usual style of this blog in that it is an overview of one particular book, Gustav Radde’s Crimean Tatars, originally published in Russian in 1856-1857.* Given the group’s centrality to the current events, it is interesting to examine what Crimean Tatars were like, or at least appeared like to a foreign traveler, before their Sovietization in the 1920s and 1930s, their deportation of 1944 and subsequent return to Crimea after 1991, and the recent annexation of Crimea by Russia. The quotes below are reproduced from the 2008 reprint of the book, in my translation.)
Gustav_RaddeGustav Radde, author of Crimean Tatars, was an interesting character. Born in 1831 in the German-speaking city of Danzig (then part of Prussia, today Gdańsk, Poland), Radde ended up being one of the tens of thousands of ethnic Germans who settled in Russia. The primary reasons for his immigration were scientific rather than economic, as Radde was driven by his fascination with Russia’s diverse landscapes, ecosystems, and peoples. A boy of curious disposition who studied local flora and fauna and collected butterflies, he grew up to be an intrepid naturalist and explorer of international renown. When he was twenty years of age, Radde received a small stipend from Danzig Naturalist Society and a visa to Russia. He then bravely embarked on a solo expedition to Crimea, where he spent the following three years, till the beginning of 1855. His visit largely overlapped with the Crimean War, which lasted from October 1853 through February 1856. Radde described what he called “the horrors of war” in his (unfinished) autobiography:
“Everyone blindly submitted to the general enthusiasm; and if anyone shrugged his shoulders or shook his head in doubt, he was immediately declared an enemy of Russia. But then everything changed quickly. … Everyone grew quiet, afraid. Caravans of wounded are brought to town, but nothing there is ready; volunteers help somewhat but it is not enough. … Only extraordinary measures prevented a massive flight of Simferopol’s residents and with the governor at their head. Everywhere help was needed but there was nowhere for it to come from.”
After his Crimean trip, Radde traveled to eastern Siberia, visited Lake Baikal and the Amur River region in Russia’s Far East, and explored the upper Yenisey and upper Ob’ areas of southern Siberia. The photo on the left shows him during his 1857 Amur River expedition. In 1860, Radde decided to move to Russia permanently and received Russian citizenship and a position in Saint-Petersburg Zoological Museum. In the summer of the following year, he traveled to Finland, which was at the time part of the Russian Empire, where he admired “all the beauties of the northern landscape with its forests, lakes, granite outcroppings and waterfalls”. In 1862, Radde went to the Caucasus, also part of the Russian Empire at the time, which he later called his “dear and beautiful second motherland”. There too he found himself in the midst of a war, as Russia was making its final stand against the Circassians. In February 1864, Radde was officially hired to conduct a bio-geographical exploration of the Caucasus, just as the Circassians were being expelled from their homeland. Subsequently, he traveled to Armenia, Northern Khorasan (in Central Asia), India, Indonesia, Ceylon, the Mediterranean, northern and northwestern Africa, and elsewhere. Several of his trips were to accompany Russian royals, the Grand Duke Alexander and Sergei (grandsons of Nicholas I), and later Grand Duke George (son of Emperor Alexander III).
Radde’s monograph Crimean Tatars was published in 1856-1857 in two issues of the Vestnik of Russian Imperial Geographical Society. Later, especially in the Soviet period, this work was essentially forgotten and never reprinted. After the fall of the Soviet Union several excerpts were reprinted in other ethnographic publications, and in 2008 the book was reprinted in its entirety, together with Radde’s unfinished autobiography, by the Ukrainian publishing house Stilos. This book, with its high quality color images, both reproductions of 19th century engravings and contemporary photographs, is a real gem. The text itself is interesting for a number of reasons. On the one hand, it is a classical work of the 19th-century ethnography genre, dealing with the predefined set of topics including the emergence of the ethnic group, customs and traditions, religion and education, clothing, “ethnic character”, and more. (Surprisingly, Radde had nothing to say about the Crimean Tatar language, another traditional item in the 19th-century “prix fixe menu” of topics in an ethnographic work. This gap probably stems from Radde’s apparent lack of interest in language in general: he made little if any effort to learn the languages of the peoples he encountered in his travels. See also note at the end of this post.)
Although it has all the requisite components of a scholarly ethnography tome, Crimean Tatars reads not as a purely scholarly monograph but more as a travelogue; I can almost see it as a script for a Travel Channel show… “On the Road with Radde”, or some such! The book’s subjectivity is hard to miss: now and again, Radde interrupts his narrative with poetic descriptions of the landscape that are more characteristic of Romantic 19th-century literature than of scholarly discourse. It is also clear that the book is written by a non-Russian traveler: Radde points out numerous things that are peculiar to him as a German but which a Russian traveler would not have found noteworthy. Similarly, Radde’s many mentions of “our” customs are meant to refer to the practices of the Germans.
As is the case with any serious ethnographic work of that time, Radde’s description of Crimean Tatars begins with their physical appearance in “racial” terms. He describes them as “Mongoloid” in appearance: “short and stooping stature; yellowish and dark facial color, often shading into dark-red; dark eyes; small and almost always flattened nose; black hair and thin beard”. But Radde also notes that the three geographically distinct groups of Crimean Tatars—those living in the steppes of Northern Crimea, the mountain Tatars, and those living on the southern shore of the Peninsula—have distinct physical appearance, with the abovementioned “Mongoloid type” being most characteristic of the steppe Tatars. Those living in the mountains are described as “tall and well built, facial color is lighter, closer to the Caucasian people, eyes big and dark, hair and beard thick and black”. (It is not clear whether Radde’s “Caucasian people” means those living in the Caucasus or the Caucasians in the racial sense, the “white people”.) The inhabitants of the southern shore of Crimea have the most “Greek blood” and look more European; they are described as “tall and stocky, their facial color is dark but not yellow [as with the northern Crimean Tatars], the face is oval and nice; nose is straight, often similar to that of the Greeks and Romans; hair and eyes black”.
Curiously, some of the physical characteristics that Radde takes note of are described as being not inborn but acquired. For example, their ears are said to stick out away from the head at the top due to the Crimean Tatars’ habit of wearing heavy lambskin hats. Women are described as having paler skin “than what is found among Caucasian women of lower classes”—which is ascribed by Radde to their tradition of covering their faces when outdoors or otherwise in public. This observation is followed by a curious departure from the racialist views prevalent in ethnography and anthropology of his day—namely that the darker facial color of Crimean Tatar men “does not depend on the presence in their skin of a coloring pigment, but is a consequence of the influence of climate and air”.
*Given that most of Radde’s other works were written in German, I assume that Crimean Tatars was also written in German. This is particularly likely since Radde admitted in his autobiography that he knew not a word of Russian when he first came to Russia in 1852 and had a hard time communicating during his stay in Crimea, except with the educated elites (who spoke German and/or French) and the Yiddish-speaking Jews. It is, therefore, hardly likely that he could write a specialized monograph in Russian shortly after his Crimean trip. However, I am not able to find information about the book being translated from German into Russian. The 2008 edition that I have merely notes that the editors changed the old, pre-Revolutionary orthography of the mid-19th century publication, retaining “the author’s stylistics and 19th century toponyms”.
(To be continued…)
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Factors affecting the weather resistance of PVC plastic windows and measures to prevent aging
Polyvinyl chloride (PVC) plastic window has many advantages and characteristics, it is more resistant to corrosion than wooden windows and steel windows; it has better sealing, sound insulation and thermal insulation properties than aluminum windows and steel windows, and it has exquisite appearance and easy maintenance. It is versatile and can be coordinated with various buildings. However, when rigid PVC is used as a window frame, especially for exterior window profiles, it needs to be exposed to the outdoors for a long time. It is subject to atmospheric environmental erosion such as wind, sun, rain, environmental pollution, etc., and the environmental damage factors are extremely complicated. The problems in the selection of resins, additives, and molding processes of raw materials make weather resistance an important indicator for people to evaluate the quality of PVC plastic windows.
1 Factors affecting the weather resistance of PVC plastic windows
The weather resistance of PVC mainly refers to the problem of aging. PVC is a synthetic polymer material. The causes of aging of polymer materials are due to both internal and external factors. The internal factor mainly refers to the molecular structure state (including chemical structure and physical structure) of the polymer material itself and the nature and proportion of each component in the polymer material system. The structural state of the polymer material and its composition formula largely determine the pros and cons of the aging resistance of the material. External factors refer to external environmental factors.
1.1 The internal factors affecting the weather resistance of PVC plastic windows The weakness of the molecular structure of PVC itself is the main internal factor that affects its weatherability. Under normal conditions, the molecular structure of PVC is a regular linear molecular chain formed by connecting vinyl chloride monomers in a head-to-tail manner. Chlorine and hydrogen atoms are only combined with secondary carbon atoms, which is supposed to be relatively stable. However, in actual production, especially when the polymerization temperature is high, irregular connections such as "head" and "tail" may be generated, as well as double bonds, branches, etc., and the presence of initiators, impurities, etc. may also affect the molecules of PVC. Structure and purity. The "head" and "tail", the connected irregular structure lead to poor thermal stability of PVC, and easy to remove hydrogen chloride (HCL). The presence of double bonds, especially the unsaturated double bonds formed at the ends of the molecular chain, is also a structural weakness, they are easily oxidized, broken, etc., and the unstable allyl chloride contained therein is also easily released. When a branched chain is present, the tertiary or tertiary hydrogen atom at the branching point is a site susceptible to attack during the aging reaction because their chain energy is low, and in particular, the tertiary chlorine chain is more susceptible to activation. The tertiary chlorine at the branching point can react with the adjacent H to remove HCl even during polymerization, and then generate a double bond structure in the molecular chain. When a peroxide is used as an initiator or aerobic in the polymerization process of PVC, a group such as -OH or -0 can be contained in the molecular chain, which is an inducing factor for subsequent aging and performance degradation.
1.2 External factors affecting the weather resistance of PVC plastic windows
The external factors affecting the weather resistance of PVC mainly include energy factors such as light (wavelength, intensity), radiation, heat, force and electricity, as well as air, reactive gas, oxygen, ozone, H2S, SO2, HCI, water, organic solvents, and microorganisms. Environmental factors such as hazards and insect damage are the main factors that cause aging of PVC and other polymer materials during storage or use. From the main mechanism of PVC aging, the aging caused by light, heat and oxygen is the main factor affecting the weatherability of PVC.
(1) The effect of ultraviolet radiation The weathering problem mainly refers to the destructive effect caused by light. Photoaging is mainly the destruction of polymer materials by ultraviolet rays (UV) with shorter wavelengths and higher energy. UV irradiation has a great influence on the weather resistance of PVC plastic windows. The UV wavelength is 200-380 nm, which has enough energy to cause chemical bonds of PVC molecules to break and generate free radicals. Table 1 lists the energy of the bond energy of the C-H bond and the C-CI bond in the PVC molecule compared to the UV wavelength.
As can be seen from Table 1, UV with a wavelength of 290 nm has an energy of 418 kJ, which is sufficient to break the C-H bond and the C-CI bond in the PVC. The UV with a wavelength of 300 nm, which has an energy of 397 kJ, is also sufficient to break the C-CI bond. It can be seen that UV with a wavelength of 290-300 nm is extremely destructive to the bulk structure of PVC, and in fact, UV with a wavelength of 310 nm can cause the C-CI bond in the PVC molecule to break out of the HCI to form a polyene conjugated double bond. Lead to aging, especially in the presence of oxygen, water, heat, PVC plastic window will appear crack, embrittlement, whitening, etc., and lead to a significant drop in impact strength, tensile strength and electrical insulation properties.
(2) Temperature, humidity and oxygen effects Temperature also plays an important role in the aging process of PVC, which is related to the temperature at which it is used. The surface temperature of the PVC plastic window used outdoors is not high (close to the ground temperature), which is not enough to cause the PVC to immediately decompose. However, since the PVC plastic window absorbs the infrared rays in the sunlight and converts it into heat energy, the surface temperature is high, especially the mutual influence of light, oxygen and the like, so that the heat accelerates the aging of the PVC plastic window, and the higher the temperature, The faster the photoaging degradation rate. Tests have shown that for every 10 °C increase in temperature, the degradation rate is twice as fast. This involves the problem of light and thermal stability of colored, especially brown, dark profiles. Different color plastic windows have different surface temperatures at the same temperature, and the light and thermal stability will be significantly different. Table 2 lists the surface temperatures of black and white PVC plastic windows under sunlight. It can be seen from Table 2 that the surface temperature of the white PVC plastic window is small compared with the air temperature. Therefore, it is recommended to use a white PVC plastic window in the higher temperature zone or a colored composite window on the outside. In addition, the alternating thermal and cold temperatures that occur with the seasons and day and night also have a certain impact on the aging of PVC plastic windows.
PVC is easily decomposed by heat and is more intense if oxygen is present. Table 3 compares the speed of thermal oxidative degradation of PVC in oxygen, air, and nitrogen. As can be seen from Table 3, PVC is the fastest to remove HCI under an oxygen atmosphere.
Humidity is also an important factor affecting the aging of PVC plastic windows. At the same temperature, the temperature is much faster in very humid areas than in dry areas. When the climate is dry, the ozone disperses and disappears. In a humid climate, ozone adheres to water droplets and becomes temporary oxidized water. Contact with PVC plastic windows can also oxidize PVC plastic windows.
In addition, geographical location and other conditions such as wind, dust and atmospheric pollution have a certain impact on the aging properties of PVC plastic windows.
2 Measures to prevent aging of PVC plastic windows
2.1 Selection of impact modifiers At present, there are three main types of impact modifiers suitable for PVC window (door) profiles, namely chlorinated polyethylene (PE-C), (ethylene/vinyl acetate) copolymer (E/VAC), Acrylate copolymer (ACR).
PE-C modified PVC is the earliest application, but the narrow processing range of this product will cause the product to turn yellow and other phenomena, showing a significant reduction trend in the market.
The annual consumption of E/VAC is the largest among the three impact modifiers, accounting for more than 55%. However, due to the narrower extrusion temperature range and lowering the Vicat softening temperature, the amount of use begins to decrease.
ACR has the advantages of low melting temperature, good processing fluidity, wide processing temperature range, etc. The appearance of the product is white, smooth and fine, and has excellent impact strength and weather resistance. The use of ACR modifiers will be an effective way to improve the weatherability of PVC plastic windows.
2.2 Selection of stability system
In addition to the thermal stability, the stabilizer in the PVC plastic window profile must have both weather resistance and processability. The most commonly used thermal stabilization systems are lead salts, cadmium-cadmium and organotin. They are ideal heat stabilizers for PVC, and some of them have strong light and heat stabilization effects.
The lead salt stabilization system has the best effect and low price. It has good processing fluidity, thermal stability and aging resistance when used in combination with metal soaps and lubricants, and it has a large proportion in PVC processing at home and abroad. It has a good stabilizing effect on PE-C modified PVC.
The thermal stability of bismuth is good, the light stability of cadmium is good, and the bismuth-cadmium stabilization system has both light and heat stability, and is suitable for outdoor use. If lead is combined with a lanthanum-cadmium stabilizer, the photostability and weather resistance can be further improved, and the degree of whitening of the product can be reduced, but the toxicity of cadmium is large.
Among the organotin stabilizers, tin mercaptide has good thermal stability but poor weather resistance. The best weathering resistance in tin is dibutyltin dilaurate and tin maleate.
2.3 Selection of colorants Years of experience at home and abroad have shown that white plastic doors and windows can be used as durable building materials. The rutile TiO has a cubic structure, has a high density, a stable crystal structure, a large refractive index, can effectively scatter light, has high optical stability, and has a remarkable protective effect on materials, and is suitable for outdoor use. Rutile TiO2 is the most ideal colorant for white plastic windows, and it also has the function of shielding and scattering ultraviolet rays.
Under the general climatic conditions in China, 4-6 parts of TiO2 can be used in the manufacture of PVC plastic window profiles, and the dosage can be appropriately increased in areas with high light radiation and high temperature. If an organotin stabilization system is used, 12 to 15 parts of TiO 2 are required.
For colored PVC plastic window profiles, pigments with a temperature resistance of 200 ° C or higher, light resistance (7 to 8 grades), acid and alkali resistance (> grade 4), and migration resistance (grade 5 or higher) are used as colorants. It is also possible to use a composite co-extrusion process, which is extruded on the outer surface of the white profile with a thin layer or film of polymethyl methacrylate, and a post-processing method can be used.
2.4 Selection of UV absorbers and antioxidants In the PVC plastic window profile formulation, if a system with good light and heat stability, such as lead dibasic phosphite in lead stability system, not only has good thermal stability, but also has good ultraviolet shielding effect. It also has the function of antioxidants, and the system also has TiO2 which can shield and scatter ultraviolet rays, so it is generally unnecessary to add UV absorbers and antioxidants. However, in areas where the climate is hot and the light radiation is strong, in order to further improve the weather resistance, an ultraviolet absorber such as UV-531 or UV-9 may be added in an appropriate amount. However, it is worth noting that the matching of such auxiliaries with other auxiliaries has a strong selectivity.
3 Conclusion
There are many factors affecting the weather resistance of PVC plastic windows. The weather resistance of PVC plastic windows depends on the influence of the atmosphere when the quality of the products is guaranteed. The atmospheric environment factor is a variable that changes with the seasons and time, and also varies with geographical conditions. Among them, ultraviolet light is the main factor for aging PVC materials, and the combination of heat and moisture will also degrade PVC materials. At the same time, it is known from the aging mechanism of PVC materials that the aging process of PVC window frame profiles is mainly the process of cross-linking and breaking the polymer chains under the combined action of light, heat and oxygen to cause discoloration and strength drop. In the process, the selection of good modifiers, stabilizers, colorants, UV absorbers and antioxidants is the most important measure to prevent aging of PVC plastic windows and improve the weather resistance of PVC plastic windows.
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Adolph Mongo
Adolph Mongo is an American born political commentator and strategist. Mongo has served as a consultant and strategist for several Detroit mayors, which includes Coleman A. Young, and Kwame Kilpatrick. He also serves as a consultant for Matty Moroun, the owner of the Ambassador Bridge that links Detroit to Canada. It is the busiest international crossing in the U.S.
Services: Political Consultant
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Barrel Shaped Con Rod 2
Harold Hall
Workshop Processes
Because of this I used the 1/4" extension to turn a 3/8" diameter spigot at each end. This could then be held in a collet chuck being a very much safer method. I did though remove the bulk of the metal, converting the rectangular shape into a circle, whilst holding one end in the four jaw and supporting the other with the tailstock centre, also at this stage producing the spigot at each end.
Photograph 1 shows the first end having been machined and from this you should be able to see evidence of the tool being fed in at regular intervals along its length, also the spigot at the tailstock end. I did though initially, partially reduce the diameter in a few stages at the smaller end to avoid too deep a cut being required to produce the final result. Having completed the first end the con rod was turned end on end and the process repeated. The finishing stage, filing and emery paper, took about 30 minutes but would have been substantially reduced had I had a much finer file. Taking out the filling marks took about 25 minutes, in all though it was an easy process. The overall system worked well as should be evident by the photographs of the finished barrel, Photograph 2 and 3.
Machining the barrel is though only part of the task as calculating the changes in diameter along its length can be a lengthy task if done purely manually, with a basic calculator of course. A programmable calculator will make the process much quicker.
Considering first the manual method, the first calculation is to determine the radius that produces the barrel form, Sk 2 showing the basis of the calculation. In this R = the radius required with VD the distance between the smallest and largest diameters along the barrel and HV the difference between the smaller radius and larger radius.
VD stands for vertical distance and HV horizontal variation.
Using Pythagoras's theorem we get R² = VD² + (R - HV)²
Requiring R this can be rearranged to give the formula indicated in the sketch.
Next stage is to calculate the tool infeed at each position, this shown for a single position in Sk. 3. Again we use Pythagoras's theorem which gives
R² = IVD² + (R - IHV)²
See the sketch to see how this can be rearranged to calculate the required value, IHV.
Con Rod, Barrel shaped, Machining
Con Rod, Barrel shaped, Machining
Con Rod, Barrel shaped
All pictures can be clicked on to provide a larger view
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Tips on How to Relieve Anxiety and Stress
Saturday, January 19, 2013 posted by admin 7:18 pm
It begins with alarm. The muscles, particularly in the face and neck, tighten. The stomach feels knotted. The pulse is rapid, the mouth is dry, and the palms are sweaty. Lactase, a substance released during muscle contractions, appears in the blood. Hormones that speed up the heart and constrict the blood vessels are released. Blood pressure rises.
All of these things constitute to a condition that people commonly know as stress or anxiety. Experts define it as the bodys nonspecific response to any demand made upon it.
After this initial response, the body returns to normal, but maintaining normalcy under stress and anxiety requires all the energy of mind and body. If the stress and anxiety continue long enough, normal functioning cannot be maintained, and the initial alarm responses reappear.
In fact, experts say that even a small amount of additional stress and anxiety at this stage can cause breakdown. Scientific reports show that in small animals, stress beyond the point of endurance has proven deadly.
So how do people manage stress and anxiety? What are the ways on how on how to relieve anxiety and stress? Here are some great tips you must muster to fight back stress and anxiety and live your life to the fullest.
1. Exercise
Regular exercise helps to relax a tense body and a stressed mind because it helps uplift depression and improve mood. It can also decrease the activity of the sensory receptors in the muscle, which send information to the central nervous system. Tension makes these receptors oversensitive so that they bombard the nervous system with electrical impulses.
Exercise can also cut down on the overload on the nervous system by quieting the electrical signals from the muscles. Best of all, exercise induces and enhances the ability to sleep restfully.
2. Take out a multivitamin or mineral insurance policy
Physiological and emotional stress can rob the body of important nutrients, including antioxidant vitamins. In times of stress and anxiety, free radicals, such as unstable molecules of harmful chemicals, can increase and sack the bodys health fragments for substitute electrons, parting uninhibited radicals and impaired tissues and cells in their body.
Anti-oxidants, most particularly vitamins E, beta-carotene, and vitamin C protect the bodys healthy fragments by giving up their personal electrons to counteract free-radical attackers. So to arm yourself against a stress-induced free-radical invasion, take a daily multivitamin or mineral induced supplement.
How Does Exercise Acts as Tranquilizer?
Scientists do not understand the precise how and why yet. They believe that certain brain chemicals found in relaxed states are released during exercise.
In experiments with cats, researchers found that the activity of the muscle receptors was reduced when the temperature of the receptors themselves or of the hypothalamus, a region in the brain, was raised. Vigorous exercise is one way of raising these temperatures and, perhaps, of slowing the receptors activity.
Some investigators suggest that the tightening of the muscles associated with tension causes chronic over-arousal and over-activity of the nervous system. Moving the muscles, they say, may be necessary to keep the muscle receptors transmissions to the nervous system at a normal level.
Mental health professionals have begun to study the effects of exercise on emotional disturbances. No one is suggesting that people can quite literally run away from our problems, but one psychologist did find that depressed patients improved significantly after ten weeks of jogging.
All of these things are boiled down to the fact that exercise is one of the best solutions to relieve people from stress and anxiety.
Category : Mental Health
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Image: How can you keep anxiety at bay? Experts suggest consuming more of these nutrients
(Natural News) More and more studies are coming to light that show the impact of food on mental health, particularly mental disorders like anxiety.
Registered dietitian and functional medicine practitioner Ali Miller says that eating certain foods can counteract the harmful effects of anxiety and anxiety-related disorders.
Food can affect mental health
Miller notes that humans’ primal fight-or-flight instinct isn’t suited for modern stressors like deadlines or financial problems. For this reason, these stressors can trigger primal responses that exaggerate one’s perception of stress.
It also doesn’t help that stress can often cause people to indulge in sugar-rich foods and junk foods. According to Miller, these foods can cause blood sugar spikes and, in turn, mess up a person’s mood, affect his appetite and trigger hormonal imbalances.
Eva Selhub, an internal medicine specialist based in Massachusetts, notes that about 95 percent of serotonin, the neurotransmitter thought to regulate anxiety and anxiety-related disorders, is produced in the gastrointestinal tract.
As bizarre as it may sound, this brain-gut connection suggests that food can affect mood, feelings and other aspects of mental health. Miller also says that foods rich in mood-stabilizing nutrients, antioxidants and other beneficial compounds are best consumed for optimal mental health.
5 Best nutrients for anxiety
Eating foods rich in brain-boosting nutrients is key to minimizing symptoms of anxiety and keeping anxiety-related disorders at bay.
Here are some of the top nutrients that Miller recommends for better stress resilience and anxiety management. Try to eat them daily as part of a balanced diet to reap their benefits.
Studies show that magnesium is capable of suppressing the stress hormones cortisol and adrenaline. Its natural relaxant effects are also beneficial for treating physiological symptoms of anxiety, such as shortness of breath, restlessness, tremors and fatigue.
Magnesium has also been found to prevent stress hormones from crossing the blood-brain barrier, protecting the brain from a possible influx of stress hormones. Common dietary sources of magnesium include spinach, cacao, almonds, peanuts and pumpkin seeds, among others.
Choline is a key player in the production of the neurotransmitter acetylcholine, which aids in regulating the brain’s stress response. Recent studies suggest that it is instrumental in stalling mental decline.
Choline can be found in beef and chicken liver, eggs and milk. It can also be found in broccoli and peanut butter.
B vitamins
Several B vitamins are hailed for their protective effects against anxiety. Vitamins B5, B9 and B12, in particular, are some of the most potent B vitamins for regulating stress, mitigating the effects of anxiety and reducing symptoms of depression.
B vitamins can be found in a number of foods, including eggs, legumes, seeds, nuts and fruits. (Related: An essential guide to understanding B-vitamins.)
L-theanine is a unique amino acid found in tea and mushrooms. Recent studies suggest that it offers a range of mental health benefits, including better mental performance, reduced stress and enhanced mood.
L-theanine has also been found to influence the production of chemical messengers in the brain, such as dopamine and serotonin, which are responsible for mood, sleep and emotion. In addition, L-theanine can modulate levels of the stress hormone cortisol.
Live microorganisms called probiotics are known for their beneficial effects on gut health. But recent studies suggest that supplementing with probiotics can also decrease anxiety.
As mentioned earlier, the gut also produces the mood-stabilizing hormone, serotonin. Therefore, eating foods that support gut health, such as those rich in probiotics, helps ensure that the gut continues to produce adequate amounts of serotonin.
Eating the right foods and maintaining adequate levels of brain-boosting nutrients can not only help keep anxiety and anxiety-related disorders at bay, but also minimize the harmful effects of stress on the brain and on mental health.
Read more articles about brain-boosting foods and nutrients at
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Lapo gyslos.jpeg
Leaf of P. tremula
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Malpighiales
Family: Salicaceae
Tribe: Saliceae[1]
Genus: Populus
Type species
Populus tremula
Sections and Species
See text
The genus has a large genetic diversity, and can grow from 15–50 m (49–164 ft) tall, with trunks up to 2.5 m (8 ft 2 in) in diameter.
Male catkins of Populus × canadensis
The bark on young trees is smooth, white to greenish or dark grey, and often has conspicuous lenticels; on old trees, it remains smooth in some species, but becomes rough and deeply fissured in others. The shoots are stout, with (unlike in the related willows) the terminal bud present, the leaves are spirally arranged, and vary in shape from triangular to circular or (rarely) lobed, and with a long petiole; in species in the sections Populus and Aigeiros, the petioles are laterally flattened, so that breezes easily cause the leaves to wobble back and forth, giving the whole tree a "twinkling" appearance in a breeze. Leaf size is very variable even on a single tree, typically with small leaves on side shoots, and very large leaves on strong-growing lead shoots, the leaves often turn bright gold to yellow before they fall during autumn.[3][4]
The flowers are mostly dioecious (rarely monoecious) and appear in early spring before the leaves. They are borne in long, drooping, sessile or pedunculate catkins produced from buds formed in the axils of the leaves of the previous year, the flowers are each seated in a cup-shaped disk which is borne on the base of a scale which is itself attached to the rachis of the catkin. The scales are obovate, lobed, and fringed, membranous, hairy or smooth, and usually caducous, the male flowers are without calyx or corolla, and comprise a group of four to 60 stamens inserted on a disk; filaments are short and pale yellow; anthers are oblong, purple or red, introrse, and two-celled; the cells open longitudinally. The female flower also has no calyx or corolla, and comprises a single-celled ovary seated in a cup-shaped disk, the style is short, with two to four stigmata, variously lobed, and numerous ovules. Pollination is by wind, with the female catkins lengthening considerably between pollination and maturity, the fruit is a two- to four-valved dehiscent capsule, green to reddish-brown, mature in midsummer, containing numerous minute light brown seeds surrounded by tufts of long, soft, white hairs which aid wind dispersal.[3][5]
Poplarsu of the cottonwood section are often wetlands or riparian trees, the aspens are among the most important boreal broadleaf trees.[3]
Several species of Populus in the United Kingdom and other parts of Europe have experienced heavy dieback; this is thought in part to be due to Sesia apiformis which bores into the trunk of the tree during its larval stage.[6]
A Populus on a hill through April, September, October, February (Germany)
The genus Populus has traditionally been divided into six sections on the basis of leaf and flower characters;[4][7] this classification is followed below. Recent genetic studies have largely supported this, confirming some previously suspected reticulate evolution due to past hybridisation and introgression events between the groups, some species (noted below) had differing relationships indicated by their nuclear DNA (paternally inherited) and chloroplast DNA sequences (maternally inherited), a clear indication of likely hybrid origin.[8] Hybridisation continues to be common in the genus, with several hybrids between species in different sections known.[3][9]
Selected species[edit]
Populus nigra in autumn
Fastigiate black poplar cultivar of the Plantierensis group, in Hungary
Poplars dominate the flora of Khorog City Park, Gorno-Badakhshan, Tajikistan
Many poplars are grown as ornamental trees, with numerous cultivars used, they have the advantage of growing to a very large size at a rapid pace. Almost all poplars take root readily from cuttings or where broken branches lie on the ground (they also often have remarkable suckering abilities, and can form huge colonies from a single original tree, such as the famous Pando forest made of thousands of Populus tremuloides clones).
A simple, reproducible, high-frequency micropropagation protocol in eastern cottonwood Populus deltoides has been reported by Yadav et al. 2009.[10]
Traditional Pamiris house
Its flexibility and close grain make it suitable for a number of applications, similar to those for willow, the Greeks and Etruscans made shields of poplar, and Pliny also recommended poplar for this purpose.[11] Poplar continued to be used for shield construction through the Middle Ages and was renowned for a durability similar to that of oak, but at a substantial reduction in weight.
Art and literature[edit]
Some stringed instruments are made with one-piece poplar backs; violas made in this fashion are said[citation needed] to have a particularly resonant tone. Similarly, though typically it is considered to have a less attractive grain than the traditional sitka spruce, poplar is beginning to be targeted by some harp luthiers as a sustainable and even superior alternative for their sound boards:[15] in these cases another hardwood veneer is sometimes applied to the resonant poplar base both for cosmetic reasons, and supposedly to fine-tune the acoustic properties.
Popular music; in Billie Holiday's Strange Fruit lyric she sings "Black bodies swinging in the southern breeze Strange fruit hanging from the poplar trees…".
Poplars in Ukrainian folklore symbolise beauty or loneliness of a woman in love.[citation needed]
The Odd Poplars Alley, in Iași, Romania, is one of the spots where Mihai Eminescu sought inspiration in his works (the poem "Down Where the Lonely Poplars Grow"); in 1973, the 15 white poplars still left (with age ranges between 233 and 371 years) were declared natural monuments.[16]
Susceptible to termites[edit]
In Pakistan, poplar is grown on commercial level by farmers in Punjab, Sindh, and Khyber Pakhtunkhwa Provinces. However, all varieties are seriously susceptible to termite attack, causing significant losses to poplar every year. Logs of poplar are therefore also used as bait in termite traps (termaps) for biocontrol of termites in crops.
Land management[edit]
Logs from the poplar provide a growing medium for shiitake mushrooms.[17]
See also[edit]
2. ^ Joint Genome Institute, Populus trichocarpa
6. ^ Martin-Garcia, J. "Patterns and monitoring of Sesia apiformis infestations in poplar plantations at different spatial scales". Journal of Applied Entomology.
10. ^ http://www.springerlink.com/content/553472252334p7kq/fulltext.pdf
11. ^ [1] The Cambridge Companion to Archaic Greece, p.69.
12. ^ Poplar cultivation in Europe
13. ^ Aiken, Laura (18 April 2012). "Baking Bread Abroad". Bakers Journal. Simcoe, Ontario.
15. ^ [2] Rees Harps Website, "Harp Myth #8".
16. ^ Iași - the county of centuries-old trees
17. ^ Shiitake growth studies performed by RMIT
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What Are the Different Capsicum Diseases?
Article Details
• Written By: Kay Paddock
• Edited By: Jenn Walker
• Last Modified Date: 10 July 2017
• Copyright Protected:
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Capsicums, also commonly called peppers in North America, are plants that are prone to several different types of diseases. Some of the elements that cause disease in these plants include types of fungi, bacteria and viruses. Most of the diseases that affect capsicum plants show their presence in such symptoms as rot, wilting, browning and spots. Some of them, including fungal diseases, may be visible as a type of mold or fuzz on the plant or its roots. A few of the most common capsicum diseases include powdery mildew, bacterial spot, bacterial rot and the pepper mottle virus.
There are also a number of pests that can destroy the plants as well as the peppers, which are actually the capsicum fruits. Aphids, nematodes, caterpillars and mites are some of the capsicum pests that can damage and kill plants through the act of feeding on them. Some capsicum diseases are actually spread from plant to plant by pests. The pepper mottle virus, for instance, can be spread by aphids that carry it from infected weeds.
Three basic types of fungal capsicum diseases attack the roots of peppers and other plants when the ground stays too wet. When the soil stays cool, Pythium can grow and cause the roots to brown and rot. In warmer temperatures, Rhizoctonia can grow and cause brown soft spots where the plant emerges from the soil. Additionally, Phytophthora can grow on the roots and the lower stem, turning the plants brown and causing root rot.
Fungal diseases that typically attack the plant and capsicum fruits include different types of mold and mildew, which are usually visible as spots and patches on the plants and peppers. Most of these fungal diseases can affect a wide variety of crops. Fungal diseases are difficult to treat, and some of them cannot be killed once they appear on the plants. In those cases, the plants may have to be removed while the soil is treated to kill the disease.
Viral and bacterial capsicum diseases do not generally have visible signs such as mold, but appear in symptoms as the plants wither, brown and die. These can be spread by pests, hands, gardening tools and even infected seeds. Bacterial spot, bacterial rot, mottle viruses and several kinds of tomato viruses are some of the more common bacterial and viral capsicum diseases. These diseases cannot usually be cured, and can damage and destroy everything from small garden plots to large crops.
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The St. Thomas Orphanage is a location in Fahrenheit: Indigo Prophecy, and is where the Indigo Child, Jade, resides. It is a Catholic orphanage where the children wear uniforms and are looked after by a nun.
Lucas Kane and the Oracle arrive at the Orphanage to retrieve Jade and fight each other on the rooftop. Members of the Orange Clan eventually arrive in helicoptors and chases Lucas onto the city streets where he hides in a nearby building where The A.I is waiting.
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The Office of the Supreme Leader
Rapping on kitchen utensils in weddings
Q. Is it permissible for women to rap on things, other than musical instruments, such as kitchen utensils, in wedding parties? And what is the ruling if the sound is heard outside by men?
A: Such [rapping] should be judged by the way it is conducted, i.e., if it is of what people used to do in traditional wedding parties, is not considered lahw, and no bad effect follow it as a consequence, there is no problem in doing so.
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Stratigraphic analysis of the Neogene Cacheuta Basin: a record of orogenic exhumation and basin inversion in the South Central Andes
BUELOW, Ellen K., SURIANO, Julieta, MAHONEY, J. Brian, MESCUA, José F., GIAMBIAGI, Laura B., KIMBROUGH, David L..
Año de la publicación:
2 014
2014 GSA Annual Meeting in Vancouver, British Columbia (19-22 October 2014)
Neogene synorogenic strata in the south-central Andes (28-35S) provide a sensitive record of the structural evolution of the Andean orogenic system and may be utilized to constrain the chronology of deformation and pattern of orogenic exhumation. The precise succession of thrust belt propagation and foreland basin development is a matter of debate. Analysis of the Cacheuta basin at the latitude of Mendoza, Argentina (33S) provides critical constraints on basin evolution and orogenic exhumation. The Cacheuta basin is subdivided into five distinct formations [Divisadero Largo, Mariño, La Pilona, Tobas Angostura and Río de los Pozos] that reflect episodic sediment flux produced during eastward thrust belt propagation. Stratigraphic analysis, U/Pb geochronology, conglomerate clast counts, and (U-Th)/He analyses constrain basin evolution and subsequent inversion. A ca. 17.9 Ma U/Pb age from a volcanic tuff near the base of the succession constrains initial basin subsidence to >18 Ma, and suggests that previous magnetostratigraphic age constraints require revision. Provenance analysis identifies episodic sediment flux from the Cordillera Costal (JuraCretaceous zircon), Cordillera Principal (distinctive Jurassic conglomerate, Cretaceous fossiliferous limestone, and Tertiary hornblende andesite clasts) and the Cordillera Frontal (PermoTriassic clasts and detrital zircon). Results from the overlapping U-Pb crystallization ages and (U-Th)/He ages on detrital zircon confirm that the Permo-Triassic Choiyoi Group of the Cordillera Frontal has remained at upper crustal levels (<6 km) since emplacement. Evidence of sediment input to the Cacheuta basin from the Precordillera is equivocal at this time. Preliminary detrital apatite (U-Th)/He analyses suggest an estimated cooling age of approximately 6 Ma, which is interpreted to reflect basin uplift and inversion in the late Miocene.
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Editors' ChoiceCircadian Rhythm
Redox Around the Clock
Science's STKE 24 Jul 2001:
Vol. 2001, Issue 92, pp. tw3
DOI: 10.1126/stke.2001.92.tw3
Circadian rhythms are controlled by an evolutionarily conserved transcriptional feedback system whose activity fluctuates as a function of the 24-hour light-dark cycle. Extrinsic factors, such as changes in food intake, can advance or delay the circadian clock, but the mechanism by which this "entrainment" occurs remains unclear. A key regulator of circadian rhythms, Clock, is expressed in the suprachiasmatic nucleus (the brain region regarded as the master pacemaker) and regulates the expression of genes encoding other clock components. Reick et al. and Rutter et al. show that the NPAS2 transcription factor performs a function similar to Clock in the mammalian forebrain and that the DNA binding activity of both these transcription factors in vitro is regulated by the redox state of nicotinamide adenine dinucleotide (NAD) cofactors. Because changes in food intake are associated with changes in cellular redox state, the authors propose that redox control of Clock and NPAS2 activity may explain how food and other extrinsic factors entrain the molecular clock. A Perspective by Schibler et al. accompanies the two reports.
M. Reick, J.A. Garcia, C. Dudley, S.L. McKnight, NPAS2: An analog of Clock operative in the mammalian forebrain. Science 293, 506-509 (2001). [Abstract] [Full Text]
J. Rutter, M. Reick, L.C. Wu, S.L. McKnight, Regulation of Clock and NPAS2 DNA binding by the redox state of NAD cofactors. Science 293, 510-514 (2001). [Abstract] [Full Text]
U. Schibler, J.A. Ripperger, S.A. Brown, Chronobiology--reducing time. Science 293: 437-438 (2001). [Full Text]
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Industry-leading water system
Water flows only when the compactor is moving (in automatic mode) and standard pressurized spray system distributes water coverage evenly across each drum.
асфалтополагаща машина volvo p6820c t4i
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