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What is it?
The psychological state one reaches when security decisions become too numerous and/or too complex, thus inhibiting good security practices.
Why is it important?
Security fatigue can cause weariness, hopelessness, frustration, and devaluation, all of which can result in poor security practices.
Why does a business professional need to know this?
Security fatigue — feeling tired, turned off, or overwhelmed in response to online security — makes users more likely to ignore security advice and engage in online behaviors that put them at risk. Users favor following practices that make things easier and less complicated, even if they recognize that these practices may not be as secure.
Security fatigue presents a significant challenge to efforts to promote online security and online privacy. The ability to make decisions is a finite resource. Security fatigue is a cost that users experience when bombarded with security messages, advice, and demands for compliance.
Too often, individuals are inundated with security choices and asked to make more security decisions than they are able to process. Adopting security advice is an ongoing cost that users continue to experience. When faced with this fatigue and ongoing security cost, users fall back on heuristics and cognitive biases such as the following:
- Avoiding unnecessary decisions
- Choosing the easiest available option
- Making decisions driven by immediate motivations
- Choosing to use a simplified algorithm
- Behaving impulsively
Understanding how the public thinks about and approaches cybersecurity provides us with a better understanding of how to help users be more secure in their online interactions. The following steps can help users adopt more secure online practices:
- Limit the decisions users have to make for security
- Make it easy for users to do the right thing related to security
- Provide consistency (whenever possible) in the decisions users need to make


Also known as: Bone cancer, Malignant fibrous histiocytoma of bone, Cancer, bone, MFH of bone
Osteosarcoma and malignant fibrous histiocytoma (MFH) of the bone are diseases in which malignant (cancer) cells form in bone.
Osteosarcoma is the most common type of bone cancer. Malignant fibrous histiocytoma of bone is a rare tumor of the bone. It is treated like osteosarcoma.


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This journal article, published in Child and Adolescent Psychiatric Clinics of North America, outlines necessary intervention strategies for children affected by war. An ecological approach is recommended to address children's issues as a part of a community. Children should have access to psychosocial programming, including safe spaces. The report describes various programmatic methods and makes recommendations for further actions.
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source: openbmb/Ultra-FineWeb


text:
Conditions of Use
I chose oxygen because it's what we breathe and I thought it was interesting.
Oxygen was discovered by Joseph Priestly in 1774. The atomic number: 8, the atomic mass: 15.9994 AMU. The melting point is: -218.4˚C (54.750008 k, -361. 12 ˚F) The Boiling point is: -183.0 ˚C (90.15 k,-297.4˚F) Oxygen does not have a Freezing point.
Joseph Priestly was born: March 13, 1733 in a country near England. He died February 6, 1804. Joseph was in the fields of science.
I chose helium because its one of the dangerous elements.
Helium was discovered by Sir William Ramsay in 1895. The atomic number is 2, the atomic mass: 4.002602 AMU. The melting point is: - 272.0 ˚C (1.15 k, -457.6˚F). The Boiling point is: -268.93. Helium does not have a freezing point because it is a gas.
Helium was discovered by Sir William Ramsay. Sir William Ramsay was born October 2, 1852. He died July 23, 1916.
He will be remembered forever
I chose sodium because I thought it was interesting.
Sir Humphrey Davey discovered sodium. The atomic number of sodium is 11. The symbol of sodium is NA. The melting point of sodium is 97.81. The boiling point is 882.9˚C. Sodium is used in glass. It is created in nature.
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source: HuggingFaceFW/fineweb-edu


Amy Whittle
WiFi Bunker
The capsule increases personal space by punching a hole into the WiFi saturated landscape.
Personal space is often seen as a physical diameter or measurable distance between one person and another. It is often associated with the ability to feel comfortable and secure. In this modern age, however, can such a phenomenon as a digital personal space also be identified?
We spend a large proportion of our lives on the internet, where accessibility of personal information increases exponentially as time passes. Looking at the numbers of Facebook users world wide, it is as though the current generation is oblivious to this matter, happily sharing their personal data online. Other growing developments in technology also pose the same risk to ones privacy; take for example Samsung's product: their televisions could possibly be recording the conversations of consumers in their own homes. Who is to say this was not already happening? What control do we really have?
As a consumer we use and trust these transparent technologies and rarely stop to consider the consequences. How can these concerns with the internet and privacy be exploited to create personal space? i.e. can we as a consumer control or defend against this invasion of privacy creating our own private bubble?
An inflatable cubicle capsule is made from a light isolation material. The material, existing of a mylar blanket and a seperate mesh, effectively fends off WiFi signals. When walking with the capsule through a WiFi rich area, the capsule inflates and can be used by the wearer as a shield. This urban landscape, consisting of WiFi signals, has an influence on the capsules shape without effecting the users physical and digital personal space. The capsule increases personal space by punching a hole into the WiFi saturated landscape.
 speculative design
 conceptual design
 Faraday Cage
 information design
initiated by
 material research
 mylar blanket
 material research
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#304 | Claire Cusack, Artist
ClaireCusack.com | _PHONE_ | _EMAIL_
CLAIRE CUSACK lives in a world inspired by ordinary objects. Whether
in her native Texas or worldly travels, she invariably finds meaningful "trash" that she transforms into unexpected and exquisite sculptures.
Her artist materials are often gathered from urban intersections, rural roads, beaches, old garages, railroad tracks, and other surprising places. According to Cusack, many of the objects have individual voices that guide the unusual pairing and complex assembling of each piece.
In her constructions, she minimizes the use of glue and other fixatives, relying on precise furniture making techniques to ensure that parts are securely fitted. The perceived simplicity of the end result masks the artist's strenuous process and meticulous attention to detail.
Cusack's work evokes an honest passion that comes from the heart. The reinvented context of objects through her vision has many stories to tell. Ultimately, her art expresses a raw spirituality not unlike the art of many primitive cultures.


By Derek Lee
I've always loved photography and it's been a hobby of mine on and off since I graduated from high school. I love researching all the cameras and photography-related artifacts in the museum's collection. Since one of our upcoming exhibits is on cameras and photography in Edmond, I wanted to take some time to highlight one of my favorite cameras that will be featured in the exhibit. One of the oldest cameras in the exhibit will be this 1A Pocket Kodak camera that dates to the late 1920s or early 1930s.
Today, hauling this camera around and going through all the necessary steps to get a decent photograph might seem like an excessive amount of work compared to pulling your iPhone out and pushing a couple of buttons. But, 90 years ago it was extremely convenient. Kodak manufactured this camera model from 1926 to 1932. Kodak added an "iridescent" finish, which ours has, to the camera in 1929. The "A" in 1A stands for autographic, which means that the camera uses autographic film. What is autographic film? In short, autographic film allowed the photographer to write a short note about the subject being photographed directly on the film itself with a small metal stylus through a small window in the back of the camera, serving as an early labeling system of sorts. Kodak introduced autographic film in 1914, but the film never really caught on with the public and Kodak discontinued it in 1932.
autographic ad
An early ad for Kodak's autographic cameras and film; note the short description at the bottom of the negative.
So how did autographic film work?
The film contained a thin layer of carbon paper between the film and the paper backing. When the photographer used the metal stylus to write on the film, pressure from the stylus left the carbon layer translucent enough to allow light to expose the now-translucent portion of the carbon layer without exposing the rest of the carbon layer. The result is a short, handwritten note visible in the margin of the developed photograph.
What about the actual camera? Where's the lens? How the heck do you open it? And once you get it open, what's with the accordion looking thing?
The camera "folded" up.
As its name implies, this camera was meant to be carried in one's pocket – well, jacket pocket anyway. It was introduced in 1926 at a cost of around $20 ($276 today), which put it in the middle of Kodak's line of cameras. Once the camera is open, the lens slides out on rails until the arms on each side are fully extended and snap into place. That accordion-looking contraption that expands as you pull the lens out? Those are the bellows and they are made of leather.
Why are the bellows needed and what do they do?
The bellows are what make the camera a "pocket" camera; without the collapsible bellows, the camera would have been much larger and nowhere near "pocket" size. Without getting too technical, the flexible bellows allows the lens to move slightly to properly focus on the subject being photographed. The photographer would move the bellows out to focus on objects closer to the camera or move the bellows in towards the camera to focus on something farther away. So how do you move the bellows once you've extended them and the support arms are locked into place? There is a small knurled screw on the right side of the slide plate that the photographer turns to move the bellows, and lens, slightly forward and backward. On the left side of the slide plate is a scale showing the photographer what the correct distance to the subject should be in order to take a properly focused photograph.
Notice the small stylus to the left of the lens, viewfinder on top of the lens, and screw to adjust the bellows below and to the left of the lens.
The back of the camera, showing the "window" to write on the negative.
Once you have the camera open, the bellows extended, the bellows positioned properly based on the distance to your subject, and you've chosen the correct aperture and shutter speed…now what? This camera, and most "portable" cameras from the first half of the 20th century, has a waist-level viewfinder – not an eye-level viewfinder like those found on more modern cameras. In this instance, the waist-level viewfinder was cheaper and easier to produce. With older cameras like this one, that have slower shutter speeds, holding the camera steady was very important to avoid blurred photographs. Resting the camera against your waist or on a table accomplishes this better than holding the awkward camera to your eye.
Interested in cameras or photography? Be on the lookout for upcoming blog posts and plan to visit the museum to see the new exhibit in the spring.


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GNU Mach is the microkernel upon which a GNU Hurd system is based. It provides an Inter Process Communication (IPC) mechanism which the Hurd uses to define interfaces for implementing in a distributed multi-server fashion the services a traditional operating system kernel provides. Mach is particularly well-suited for SMP and network cluster techniques. Thread support is provided at the kernel level, and the kernel itself takes advantage of that. Network transparency at the IPC level makes resources of the system available across machine boundaries.
Logger is a log queueing and optimization utility. It can completely replace sys/klogd, handle logs larger than 2GB, perform automatic nightly log rotation without affecting services, and transfer logs between machines via TCP connections. Any application that writes a text log can be maintained by Logger. It is light, small, and fast, emphasizes security, and reduces drive usage through memory queueing.
tzls and tzx are commandline utilities for quickly unpacking or listing the contents of various types of common Unix archive files, which may be compressed in any of several ways. The supported compression types are bzip2, gzip, and compress. The supported archive types are tar, cpio, zip, rar, and arj. The tools are implemented as shell scripts, so no compilation is required.
fff and ffl are tools for searching for files and directories from the Unix shell with more integrated "shell-like" behaviour and simpler syntax than find(1), though find(1) is still used to perform the actual searches. In particular, there is no need to quote wildcards, and searches are case-insensitive. Matching results are shown one per line. fff displays full paths, and ffl relative paths. Detailed find(1) options can be appended to the fff/ffl command line if desired. These utilities are based entirely on shell aliases and functions, so no compliation is required.


Gifts and Celebratory Events for Employees and Nonemployees
Policy Statement
Harvard units may occasionally spend modest amounts from appropriate funding sources to recognize employees or nonemployees under certain circumstances.
Allowable employee recognition may take the form of celebratory events or gifts for the following occasions:
 - Work-related achievement
 - Employee morale-building events
 - Sympathy upon the death or serious illness of an employee or employee's immediate family member
Allowable nonemployee recognition must be for a legitimate Harvard business purpose and should be motivated by detached or disinterested generosity or respect, admiration, charity or like sentiment. Gifts to nonemployees may not be given in lieu of payment for services or as a quid pro quo.
Units must use prudent judgment and also follow the IRS rules outlined below. University funds may not be spent in recognition of personal events or achievements unrelated to work, such as birthdays, weddings, baby showers, housewarming, etc., or for gifts in recognition of holidays rather than work-related achievement.
Employee Gifts and Celebratory Events Policy Table of Contents
 1. Gift must be for an allowable reason
 2. Celebratory or employee morale building events
 3. Gifts to nonemployees
 4. General information regarding funding source and object codes
 5. Gifts given to Harvard personnel from third parties.
 Gift Taxability Table (PIN required)


were primarily responsible for the creation of ceramics in the early Greek Iron Age, which lasted from 1050 BC to 700 BC. Unfortunately, there are no written records extant which date back to that era. Indeed, pottery itself serves as much of the historical record of these times in Greece. Murray says in a new article in the American Journal of Archaeology:
"Pottery is the anchor of everything we say about the society—but I think that's problematic. No one had really thought that women were involved in making this pottery. There was no argument. It was just taken as the default."
Indeed, most indisputable historical records from all the eras in Greek history show that it was for themes part a clearly male-dominated society. However, Murray and her team posit the theory that, due to huge societal shifts which took place between the preceding Bronze Age, which represented a high point in artistic expression of every kind in Greece, and the Iron, women may have taken on new roles and begun to create pottery as well.
The Iron Age differed from the previous era in many ways — there was a measurable drop in population from the previous Bronze Age, something which, Murray says, leads to women stepping into the breach and beginning to create pottery themselves.
This situation may not have continued into what is called the Archaic Age, with its rebound in population and the concomitant social classifications which accompanied it — but for this time period, it is entirely possible, according to Murray, that females put their mark on the Ancient Greek art of fine pottery.
Additionally, as seen on the Dipylon vase above, there is a sudden and marked emphasis on geometric patterns such as zigzags and diamonds, representing an enormous change from prior pottery decoration.
Murray believes that this may actually be a recreation of the geometric patterns used in weaving — which was purely a female art at the time.
"The fact that the style seems to be inspired by textiles is kind of like the big, blaring horn. Women are almost always the weavers."
The fact that the Dipylon vase itself portrays mourners is another tell for Murray, who explains that women always had played a huge role in funeral rituals, including preparing the bodies and even being professional mourners, roles which go across nearly all human civilizations.
Additionally, most Iron Age pottery carries motifs of women's daily lives — weaving and doing other typically female chores. Later pottery from the Archaic period often was decorated with battle scenes and even poetry, retelling epic battles.
At the present time there is research being undertaken to closely examine pottery for impressions of the fingerprints of the ancient potters, which may shed light on the gender of the person who created the piece.
Julie Hruby, a classicist from Dartmouth College, is zeroing in on using this new technology to finally determine who these ancient potters might be, creating a new method for analyzing prints. She states
"I would be surprised if I found fingerprint evidence that refuted what was in (Murray's) article."
In 2007, the crew of a Dutch ship crossing the Mediterranean Sea unearthed a well-preserved ancient Greek helmet near the Israeli city of Haifa. As required by local law, the dredging vessel's owner promptly handed the find over to archaeologists from the Israel Antiquities Authority (IAA). Now, reports the Greek City Times, researchers have offered new insights on the object, which is the only intact helmet of its kind found along Israel's coast.
Crafted in the sixth century B.C., the Corinthian armor was likely used during the Persian Wars, which pitted Greek city-states against the Persian Empire in a series of clashes between 492 and 449 B.C. Kobi Sharvit, director of the IAA's Marine Archaeology Unit, said in a statement:
"[It] probably belonged to a Greek warrior stationed on one of the warships of the Greek fleet that participated in the naval conflict against the Persians who ruled the country at the time."
After spending 2,600 years on the seafloor, the helmet's cracked surface is heavily rusted. But scholars could still discern a delicate, peacock-like pattern above its eyeholes. This unique design helped archaeologists determine that craftsmen made the armor in the Greek city-state of Corinth.
According to Ancient Origin's Nathan Falde, metalworkers would have fashioned the piece to fit tightly around the head of a particular person—but not so tightly that it couldn't be swiftly and safely removed in the heat of battle.
"The helmet was expertly fabricated from a single sheet of bronze by means of heating and hammering," notes the statement. "This technique made it possible to reduce its weight without diminishing its capacity for protecting the head of a warrior."
As Owen Jarus wrote for Live Science in 2012, archaeologists excavated a similar helmet near the Italian island of Giglio, which is about 1,500 miles from where the crew found the recently analyzed artifact, during the 1950s. That headgear—also around 2,600 years old—helped modern scholars determine when craftspeople manufactured the Haifa Bay armor.
Experts speculate that the headpiece's owner was a wealthy individual, as most soldiers wouldn't have been able to afford such elaborate gear. Sharvit and scholar John Hale stated in a research summary quoted by UPI:
"The gilding and figural ornaments make this one of the most ornate pieces of early Greek armor discovered."
One theory raised by researchers speculates that the helmet belonged to a mercenary who fought alongside the Egyptian Pharaoh Necho II, per the Express' Sebastian Kettley. Another explanation posits that a Greek soldier stationed in the Mediterranean donned the headpiece, only to drop it into the water or lose it when his ship sank.
Though archaeologists aren't sure exactly who owned the artifact, they do know that the warrior sailed the seas at a time when Persia controlled much of the Middle East. As Live Science's Jarus explains in a more recent article, the Persians attempted to invade Greece around 490 B.C. but were defeated near Athens during the Battle of Marathon.
A second attack by the Persians culminated in the Battle of Thermopylae, which saw a heavily outnumbered group of Spartans led by King Leonidas mount a doomed last stand against Xerxes' Persian forces. (The 480 B.C. clash is heavily dramatized in the film 300.) But while Thermopylae ended in a Greek loss, the tides of war soon turned, with the Greeks forcing the Persians out of the region the following year.
In the decades after the Persians' failed invasions, the Greek military continued the fight by campaigning against enemy troops stationed in the eastern Mediterranean. Ancient Origins notes that the helmet's owner was likely active during this later phase of the war—"when the Persians were often on the defensive" rather than offensive—and may have served on either a patrol ship or a battleship.


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Data set ID:
We conducted a "home vs. away" plant-soil feedback greenhouse experiment using two C3 grass species (Bromus inermis and Pascopyrum smithii) grown in soil collected from Konza Prairie. We used a closed-circuit CO2 trapping method and isotopic analysis to differentiate between root-derived and SOM-derived CO2 production. We investigated how soil chemistry and soil bacterial communities differed in soils with a history of B. inermis vs soils with a history of P. smithii.
Monday, January 30, 2023
Monday, June 1, 2015 to Monday, May 1, 2017


When working with a multi-terrain setup, it often happens that you get unwanted seams or steps in your world - either on the border between two terrains, or at the edge of a stamp. This article explains how you can get rid off those seams in an elegant way with the stamper in Gaia 2 / Pro.
Our example setup: Two terrains with unaligned heights between the borders.
1. Remove all masks from the stamper. Set the Operation Type to "Set Height", then Add a Distance Mask with
Influence: Global
Axes: X or Z, depending on which axis your seam / edge runs across.
For the Distance Mask Curve set up a hill-like curve. Combined your mask settings should look like this:
You should now be seeing some "hill-like" structure that mimics the curve of the distance mask when the stamp preview is enabled, depending on the height of the stamper it should either be a hill or a valley in your existing terrains:
2. Position the Stamper exactly above the edge you want to blend away. You can experiment a bit with the height to decide at which height the transition should take place:
3. In theory you can stamp now and the two terrains will be merged according to the stamp preview. However you will notice that the seam area will look a bit bland and featureless. You can change this by adding an additional image mask, then selecting a stamp image that shows interesting features that you would like to see in the transition:
Keep in mind that you can just open the stamp browser to flip through the available stamps,the preview will update accordingly:
If you are happy with the result, you can press the stamp button, and you should see your stamp / edge being replaced with the transition you just created. Here are the two terrains from the example setup at the beginning:
If you don't like the transition taking place over such a large area across your world, you can also fine tune the curve, but if you overdo it, it might become obvious that thereis some sort of artifical transition going on between the terrains:


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Systems of Three Variables Systems of Three Variables
Systems of Three Variables
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- Solve this system. And here we have three equations with three unknowns.
- And just so you have a way to visualize this,
- each of these equations would actually be a plane in three dimensions.
- And so you're actually trying to figure out where three planes in three dimensions intersect.
- I won't go into the details here, I'll focus more on the mechanics,
- but you can imagine if I were to draw a three dimensional space over here.
- Now all of a sudden we'll have an x, y, and z axes.
- So you can imagine that maybe this first plane
- and I'm not drawing it the may it might actually look.
- It might look something like that. (I'm just drawing part of the plane.)
- And maybe this plane over here.
- It intersects right over there and it comes popping out like this and then it goes behind it like that.
- It keeps going in every direction, I'm just drawing part of the plane.
- And maybe this plane over here, maybe it does something like this.
- Maybe it intersects over here and over here.
- And so it pops out like that and then it goes below it like that
- and then it goes like that. I'm just doing this for visualization purposes.
- And so the intersection of this plane - the x, y and z coordinates that would satisfy
- all three of these constraints the way I drew them - would be right over here.
- So that's what we're looking for. And a lot of times these three equations with three unknown systems
- will be inconsistent. You won't have a solution here, because it's very possible to have three planes
- that all don't intersect in one place. A very simple example of that is
- well, one, they could all be parallel to each other, or they could intersect each other but maybe they
- intersect each other in kind of a triangle, so maybe one plane looks like that, then another plane maybe
- pops out like that, goes underneath. And then maybe the third plane cuts in.
- It does something like this: where it goes into that plane
- and keeps going out like that, but it intersects this plane over here.
- So you see kind of forms a triangle and they don't all intersect in one point
- so in this situation, you would have an inconsistent system. So with that out of the way, let's try to
- actually solve this system. And the trick here is to try to eliminate one variable at a time from all
- of the equations, making sure that you have the information from all three equations here
- so what we're going to do is we could maybe - it looks like the easiest to eliminate
- since we have a positive y and a negative y and then another positive y
- it seems like we can eliminate the Ys.
- We can add these two equations and come up with another equation
- that will only be in terms of x and z. And then we could use these two equations
- to come up with another equation that will only be in terms of x and z.
- But it will have all of the x and z constraint information embedded in it because
- we're using all three equations. So let's do that. So first let's add these two equations right over here.
- So we have x plus y minus three z is equal to negative ten.
- And x minus y plus two z is equal to three. So over here if we want to eliminate y, we can literally
- just add these two equations. So on the left hand side, x plus x is two x. Y plus negative y cancels out
- And then negative three z plus two z - that gives us just a negative z
- and then we have negative ten plus three, which is negative seven.
- So using these two equations we got
- two x minus z is equal to negative seven - just adding these two equations.
- Now let's do these two equatons. And we can reuse this equation as long as
- we're using new information here. Now we're using the extra constraint of this bottom equation.
- So we have x minus y plus two z is equal to three.
- And we have two x plus y minus z is equal to negative six.
- If we want to eliminate the Ys, we can just add these two equations.
- So x plus two x is three x. Negative y plus y cancels out. Two z minus z - well that is just z.
- And that is going to be equal to three plus negative six, which is negative three.
- So if I add these two equations, I get three x plus z is equal to negative three. Now I have a system
- of two equations with two unknowns. This is a little bit more traditional of a problem. So let me write
- them over here. So we have two x minus z is equal to negative seven. And then we have three x plus z
- is equal to negative three and the way this problem is set up, it gets pretty simple pretty fast, because
- if we just add these two equations, the Zs cancel out. Otherwise if it didn't happen so naturally, we'd
- have to multiply one of these equations, or maybe both of them, by some scaling factor.
- But we can just add these two equations up.
- On the left hand side, two x plus three x is five x. Negative z plus z cancels out.
- Negative seven plus negative three - that is equal to negative ten.
- Divide both sides of this equation by five and
- we get x is equal to negative two. Now we can substitute back to find the other variables.
- Maybe we can substitute back into this equation to figure out what z must be equal to.
- So we have two times x. Two times negative two minus z is equal to negative seven.
- Or negative four minus z is equal to negative seven.
- We can add four to both sides of this equation and then we get
- negative z is equal to negative seven plus four, which is negative three.
- Multiply or divide both sides by negative one and you get z is equal to three. And now we can go and
- substitute back into one of these original equations. So we have x. We know x is negative two.
- So we have negative two plus y, minus three times z.
- Well, we know z is three (so minus three times three)
- should all be equal to negative ten. And now we just solve for y.
- So we get negative two plus y minus nine is equal to negative ten. And so negative two minus nine,
- that's negative eleven. So we have
- y minus eleven is equal to negative ten. And then we can add eleven to both
- sides of this equation. And we get y is equal to negative ten plus eleven, which is one.
- So we're done!
- We've got x is equal to negative two. Z is equal to three and y is equal to one.
- Now I can actually go back and check it.
- Verify that this x, y and z works for all three constraints
- that this three dimensional coordinate lies on all three planes.
- So let's try it out. We've got x is negative two, z is three, y is one.
- So if we substituted - let me do it into each of them - so in this first equation
- that means that we have negative two plus one (remember y was equal to one).
- Let me write it over here - y is equal to one, x is equal to negative two, z is equal to three.
- That was the result we got. Yup, that's the result we got.
- So when we test it into this first one, you have negative two plus one minus three times three.
- So minus nine. This should be equal to negative ten. And it is.
- Negative two plus one is negative one, minus nine is negative ten.
- So it works for the first one. Let's try it for the second equation right over here.
- So we have negative two minus y (so, minus one) plus two times z (so, z is three, so two times three)
- So, plus six needs to be equal to three.
- So this is negative three plus six, which is indeed equal to three.
- So this satisifies the second equation. And then we have the last one right over here!
- We have two times x, so two times negative two, which is negative four. Negative four.
- Plus y, so plus one. Minus z, so minus three. Minus three.
- Needs to be equal to negative six. Negative four plus one is negative three,
- and then you subtract three again. It equals negative six.
- So it satisfies all three equations, so we can feel pretty good about our answer.
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At 5:31, how is the moon large enough to block the sun? Isn't the sun way larger?
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Note: When changing "the sixth branch" to "the sixth sign of the Chinese zodiac" (the former being a tad more obscure than the latter!), removed the meaning of certain hours of the day, as each of the signs has these (the day is divided using the signs) and none of the other entries mention them. The signs are also used to denote other things besides the hours, and such usage is not common except in astrological contexts anyway (when the signs are presumed to be known).
Return to "巳" page.


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This spring, venture to the Academy's rainforest dome to explore the season in bloom!
Over the year, exciting updates to the Academy's four-story rainforest will be revealed, beginning with a brand new butterfly emergence experience opening March 3.
- From inside the rainforest canopy, watch the life cycle of tropical butterflies unfold before your eyes through a new viewing chamber, including several colorful butterfly species new to the Academy's rainforest exhibit.
- Learn about the Academy's work to sustain the world's tropical rainforests and the species that call them home.
- Teeming with over 1,600 live plants and animals from rainforest ecosystems around the world, the Academy's rainforest dome features charismatic reptiles, amphibians, birds, fish, and insects.
Plus, visit the Academy from March 17–April 23 and explore the fascinating world of pollinators with a dynamic schedule of special spring programming.
- Learn all about birds and bees and the habitats and plants they help cultivate.
- See jewel-toned butterfly specimens from the Academy's entomology collection and examine up close the structural color that makes these fluttering insects so biologically diverse.
- Around the museum, special programming by visiting community partners will allow visitors to explore the sights and sounds of spring—including pop-up demonstrations by Academy Youth, pollinator talks on the living roof, butterfly-themed puppet shows, and much more.


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and others and was prepared because evaluations can be done well or they can be done poorly. They can be well thought out and executed in a methodologically rigorous way or they can be reduced to an a priori list of indicators. They can add critical, new knowledge for decision-making or they can simply reflect things that are mostly already known. Ultimately, high-quality evaluations have the power to bring about significant improvements in service delivery resulting in an improved and sustainable healthcare system for all Canadians.
Appendix 1. Proof of Concept Evaluation
A proof of concept evaluation is a method for externally and independently validating a new care delivery model using a panel of experts in the topic area.
Steps in Conducting a Proof of Concept Evaluation
Conducting a proof of concept evaluation involves the following steps:
- Evaluators obtain a consensus that the parties involved in the model are prepared to participate in a proof of concept evaluation.
- Program staff prepare a description of the model of care.
- Using the above description, and discussions with program staff, the evaluators prepare a comprehensive yet concise description of the model so that an external expert panel can understand what the model is, why it was developed, what its component parts are and how a client would be treated in the model.
- Evaluators conduct a literature and key informant scan to determine what best practices may exist for similar models, or what the key characteristics of good, similar models are.
- Evaluators develop a document which outlines an "ideal," or best practices, model and its component parts based on information collected in point four above.
- Evaluators and program staff identify key experts to be considered for the independent expert panel. Evaluators invite panel members and finalize panel membership.
- Program staff identify a key person who does not have a vested interest in the model, but who understands both the model and the context in which it operates, to participate in the panel as a resource to the experts (e.g., a knowledgeable retired or former member of the program team with the ability to objectively answer questions about the program). This is done to ensure that the experts can clearly understand the model and its context. The resource person will be required to agree to maintain confidentiality about panel discussions.
- Convene the panel of experts for a two-day review of the model.
- In advance of the meeting, provide an overview of the model to be assessed (see step three above) and an overview of best practices or key characteristics from other models (see step five above) to the expert panel. On the first day, facilitate discussions so that the experts develop a consensus on what characteristics or best practices would define an ideal model, that is, what would constitute a "gold standard."
- During the second day, the actual program model is compared to the ideal template or "gold standard" and a step-by-step determination is made as to the strengths and weaknesses of each main component, or characteristic, of the model under review.
- Based on the two-day meeting, a draft report of the findings is prepared by the evaluators and circulated back to the members of the expert panel for their review and comment.
- Based on this input, a confidential final proof of concept evaluation report is prepared and submitted to the funder, or other appropriate group or body.
About the Author
Marcus J. Hollander, PhD, is president of Hollander Analytical Services Ltd., a national health services and policy research company headquartered in Victoria, British Columbia. He can be reached by telephone at _PHONE_ or by e-mail at _EMAIL_.
Jo Ann Miller, PhD, is vice-president, research and evaluation, at Hollander Analytical Services Ltd. She can be reached by telephone at _PHONE_ or by e-mail at _EMAIL_.
Helena Kadlec, PhD, is the senior scientist at Hollander Analytical Services Ltd. She can be reached by telephone at _PHONE_ or by e-mail at _EMAIL_.
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text:
A Guide to the Philip Nolan Papers, _PHONE_
Born to Peter and Elizabeth (Cassidy) Nolan in Ireland, Philip Nolan (_PHONE_) became a noted mustanger and possible filibuster in Spanish Texas. Before arriving in Texas, Nolan worked as a bookkeeper and shipping clerk for General James Wilkinson in Kentucky and New Orleans, where he learned of business opportunities in Texas. Nolan began mustanging in 1791, though suspicions grew among Spanish authorities about his true intentions due to his connections with Wilkinson and illegal trade. A year after marrying Frances Lintot in 1799, Nolan set out with a group of well-armed men on his fourth expedition to catch horses in Texas. After building a small fortification and corrals, Nolan began catching mustangs. He was killed, however, in March 1801 by Spanish forces sent to intercept him, while his captured men were tried and imprisoned.
Composed of Photostat copies of correspondence and government documents, the Philip Nolan Papers, _PHONE_, document the Spanish reaction to his expeditions.
Jackson, Jack. "Nolan, Philip."Handbook of Texas Online. Accessed July 26, 2011.
This collection is open for research use.
Philip Nolan Papers, _PHONE_, Dolph Briscoe Center for American History, The University of Texas at Austin.
Basic processing and cataloging of this collection was supported with funds from the National Historical Publications and Records Commission (NHPRC) for the Briscoe Center's History Revealed: Bringing Collections to Light project, 2009-2011.
Detailed Description of the Papers


Summer Safety
The Massachusetts State Fire Marshall and the Carlisle Fire Department offers the following tips for a safe and happy summer.
Gasoline and Lawn Mowers
Gasoline vapors are highly flammable. They stay on your clothing and can ignite if you light a match or cigarette.
Store gasoline only in approved containers, outside, or in a building not attached to the house. Never keep gasoline inside the home.
Keep gasoline away from all heat sources such as smoking materials, pilot lights, campfires, and grills.
Never fuel a lawn mower while it is hot. Give it a few minutes to cool off first.
Keep hands and feet away from the mower while it is running.
Barbecue Safety
Use all barbecue grills away from the house in the backyard.
Supervise children whenever any grill is in use.
Never use gasoline on any grill.
Gas Grills
Keep all LP-Gas outside, three feet away from building openings such as doors, windows, dryer vents and intake vents.
All LP gas cylinders with a capacity between 4-40 lbs. must be equipped with an overfill protection device.
We recommend LP-gas canisters be ten feet away from the house, if possible, especially when in use.
LP-gas grills are not permitted inside or on balconies above the first floor of any building where people live.
LP-gas is heavier than air and sinks. A leaky grill could pose a hazard to people below. Possible ignition sources include smoking materials, air conditioners, compressors, pilot lights and cars.
Make sure all connections are tight and secure.
Charcoal Grills
Use only charcoal lighter fluid to start charcoal grills. Once coals have been lighted, never add lighter fluid to the fire - flames may travel up the stream of lighter fluid resulting in serious burns.
When your car overheats…
Turn off your car and wait at least one-half hour before attempting to open the radiator
Use a heavy rag or cloth to open the radiator.
Stand back as far as possible. Keep your face out of the way in case the radiator should rupture.
Opening hot car radiators is one of the leading causes of burns to young adults. These burns can be prevented with patience and appropriate precautions.
When you car overheats, or even when it's just been running for a while, pressure builds up in the radiator.
If you open hot car radiator, hot steam and liquid can splash your face and hands causing painful, disfiguring burns.
Enjoy the many professional, supervised fireworks displays.
This includes sparklers, party poppers, snappers, firecrackers and cherry bombs, to name a few.
It is illegal to purchase fireworks in another state and transport them into Massachusetts.
Do not purchase fireworks through mail-order catalogues. We cannot prohibit distribution of these catalogues, but we do confiscate illegal shipments of fireworks. Many consumers attempting to circumvent the law have lost both their money and their fireworks.
Burn First Aid
Stop, Drop, and Roll to extinguish a clothing fire.
Cool a burn. For minor burns, run cool water immediately over the burn.
Seek emergency medical help immediately for more serious burns.
Use sunscreen to avoid sunburn.


Several other forum members have described dataloggers for high-bandwidth datastreams, often status data from moving vehicles. I have completed a project that flexibly collects data from two or three dozen low-bandwidth sensors placed around my house, taking VC0706 pictures; measuring temperatures, pressures, water depth, power usage, and so on; and controlling relays.
The sensors are connected to peripheral stations, each built around a Teensy 3.5 and a real-time clock. The stations have identical hardware & software, but they can be configured through text files on the Teensies' uSD cards to work with different sensors and then either to use their XBee tranceivers to send the data to a central base station, or to timestamp & store received data locally.
The base station is built around another Teensy 3.5 and clock. It timestamps received data and then can store it locally for later transmission or transmit it immediately (through a USB connection) to a Windows program.
The Windows program is built around a relational database. Received data are stored in the database, and the database can be mined for graphs and statistics. Here's a sample graph:
Click image for larger version.
Name: raw graph outside.jpg
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ID: 24966
The system is described on my Web site at


From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
PronunciationSpanish: [anˈtonjo]
Portuguese Portuguese: [ɐ̃ˈtɔniu]
Brazilian Portuguese: [ɐ̃ˈtonju]
Italian: [anˈtɔːnjo]
Language(s)Bosnian, Bulgarian, Catalan, Croatian, Galician, Greek, Italian, Portuguese, Romanian, and Spanish
Name dayJune 13
Other names
See alsoAnthony, Antony, Antoine, Antonius, Antonis, Tony, Antonia, Antonietta, Antonie, Antwan, Antone, Antoni, Antoin, Antonin, and Antuan
Antonio is a masculine given name of Etruscan origin deriving from the root name Antonius. It is common name among Romance language-speaking populations as well as several Slavic countries in the Balkans, Lusophone Africa and South Africa.[1]
In the English language it is translated as Anthony, and has some female derivatives: Antonia, Antónia, Antonieta, Antonietta, and Antonella'. It also has some male derivatives, such as Anthonio, Antón, Antò, Antonis, Antoñito, Antonino, Antonello, Tonio, Tono, Toño, Toñín, Tonino, Nantonio, Ninni, Totò,, Tonini, Tony, Toni, Toninho, Toñito, and Tõnis. The Portuguese equivalent is António (Portuguese orthography) or Antônio (Brazilian Portuguese). In old Portuguese the form Antão was also used, not just to differentiate between older and younger but also between more and less important, In Galician the form is Antón, in Catalan Antò, and in Basque Antxon. The Greek versions of the name are Antonios (Αντώνιος) and Antonis (Αντώνης).
The name derives from Antonius, a well-known Latin family name, probably of Etruscan origin. The Roman general Marcus Antonius held that the origin of the name was Anthon (Ανθών), son of Hercules. This myth, recorded by Plutarch, was probably created by Marcus Antonius himself, in order to claim divine parentage. The name was in use throughout the Roman world which, at its height, comprised the whole of the Mediterranean and much of Europe as well as the Middle East. When the Roman Empire became Christian, the name continued in popularity because of the many great saints who bore the name. Later, the name was spread all around the world as Christianity was introduced to other locations (e.g. the Far East, the Americas, Australia, and Sub-Saharan Africa).
Famous male bearers[edit]
Antonio may also refer to:
Antonio as middle name[edit]
Known as Tony[edit]
Fictional characters[edit]
Antonio may refer to the fictional characters:
Other uses[edit]
See also[edit]
 1. ^ "Antonio". Retrieved October 16, 2019.
 2. ^ Schiro, Anne-Marie (18 March 1987), "Antonio Lopez is dead at 44; was major fashion illustrator", New York Times, retrieved 4 December 2009
 3. ^ (retrieved 25 Sep 2019)
Bosnian, Catalan, Croatian, Galician, Italian, Portuguese, Romanian, and Spanish


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The Brotherhood of Blades was established after the defeat of the Riven Blade; a rebel movement which attempted to overthrow the king of Rivana in favor of forming a republic. With the rebellion destroyed, the Brotherhood of Blades was founded as a band of freedom fighters, but to this day is more considered to be a group of lowly bandits and thugs who stalk the forests and roads of the Eastern Kingdoms in Norrhan.
The Brotherhood make their living by raiding trade caravans and setting up ambushes along the forest roads for hapless travelers to walk into. They swear to fight for the people, and promise to give all their stolen loot back to the common people. However, the Brotherhood keeps most of it for themselves, and commoners are just as victimized by banditry as noblemen are. In essence, the Brotherhood of Blades are nothing more but violent thugs and bandits.
Although they are viewed as villainous scum and a pestilence to the people of the Eastern Kingdoms, the members of the Brotherhood hold a tight bond with each other. Every man of the Brotherhood is more or less equal, and they weigh respect and duty to each other as their most important qualities. When a man takes on the Brotherhood's Blades on his skin, he is branded a blood brother for life, and thus he must honour his new brethren like they were his true brothers.
While all men are equal in the Brotherhood, there are those that must also lead to ensure that the Brotherhood stays strong. Any man may become a Blade Leader; that is if the man in question can win in a duel against a current Blade Leader. Each Blade Leader holds leadership over their own small band of Brothers, and it is unknown how many such bands exist. Supposedly there are Brotherhood camps all over the Eastern Kingdoms' forests. However, the Blade Leaders are merely captains, whilst the true ruler of the Brotherhood is known as the Lord of Blades. Only the strongest and most cunning of brothers can ever hope to become the ruler of the Brotherhood of Blades.


strength, solid fraction, force and fabric anisotropies, and probability distribution of contact forces. Our main finding is that, based on the energy dissipation associated with relative rotation between two particles in contact, the effect of rolling resistance can explicitly be identified with that of the number of sides in a regular polygonal particle. This finding supports the use of rolling resistance as a shape parameter accounting for particle angularity and shows unambiguously that one of the main influencing factors behind the mechanical behavior of granular systems composed of noncircular particles is the partial hindrance of rotations as a result of angular particle shape.
}, issn = {_PHONE_}, doi = {10.1103/PhysRevE.84.011306}, author = {Estrada, Nicolas and Emilien Az{\'e}ma and Farhang Radja{\"\i} and Taboada, Alfredo} } _USER_ {291, title = {Impact of Chemical Impurities on the Crystalline Cement Clinker Phases Determined by Atomistic Simulations}, journal = {Crystal Growth \& Design}, volume = {11}, year = {2011}, month = {Jul-2011}, pages = {2964 - 2972}, abstract = {
Abstract Image
The presence of chemical substitutions is believed to play a crucial role in the hydration reactions, structure, and elastic properties of cement clinker phases. Hence, substitutions are of great technological interest, as more efficient production of cement clinkers would result in a reduction of CO2 emissions, as well as possible economic benefits. Here we use a combination of classical and quantum mechanical simulation methods to study the detailed physicochemical changes of the clinker phases alite (Ca3SiO5) and belite (Ca2SiO4) when Mg2+, Al3+ and Fe3+ guest ions are incorporated into their structure. Using classical force field methods, we considered random substitutions among possible sites and different compositions in order to identify the preferential substitution sites on the crystalline structures. Then, the resulting structural changes that take place to accommodate the guest ions are investigated and discussed in detail. Using quantum mechanical density functional theory calculations the electronic structure of representative configurations has been computed to determine the potential impact of impurities on the reactivity.
}, issn = {_PHONE_}, doi = {10.1021/cg200212c}, author = {Hegoi Manzano and Engin Durgun and Mohammad Javad Abdolhosseini Qomi and Franz-Josef Ulm and Roland Jean-Marc Pellenq and Jeffrey C Grossman} }


Enslaved: A Mystery Novel
Ron Burns, Author
Ron Burns, Author St. Martin's Press $20.95 (262p) ISBN 978-0-312-10977-6
Reviewed on: 07/04/1994
Release date: 07/01/1994
In the second Harrison Hull historical mystery (after The Mysterious Death of Meriwether Lewis ), Thomas Jefferson summons Hull, soldier and frontier adventurer, to Monticello in the cold January of 1812. His mission: to track down two missing slaves (Sally Hemings's cousins) now belonging to Jefferson's Kentucky nephews. Hull's quest, fueled by constant hard drinking, takes him on horseback to isolated plantations, a thieves' hangout in a cave, a dungeon-like country jail and an Ohio River island harboring a slave-breeding farm. He witnesses a vicious flogging and the murder trial of three innocent slaves, captures some adversaries, kills others, narrowly escapes being slain several times, survives an earthquake, lets a charming villain slip through his fingers but solves the case and arrests two murderers. Though many of the players (not Hull) and events are factual, plotting and characterization are sometimes weak. Burns nevertheless paints a vigorous picture of a frontier slave state and evokes the peculiar attitudes arising from two unnatural conditions--being a slave and being a master. (July)
The Best Books, Emailed Every Week
Tip Sheet!


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Lots of information about radiation levels are available. But at first glance, these data seem incomprehensible to anyone who didn't have an advanced degree in nuclear physics. Here is a simple tutorial to calculate the biological impact of a given radiation exposure.
- Pick up your radiation measurement source :
- Tsukuba 1
- Tsukuba 2
- Tokyo (Hongo, Komaba, Kashiwa)
- Tokyo (Shinjuku)
- Average Japan by area
- Crowd-sourced from all over Japan
- If the measure is in microsievert per hour (uSv/h), divide by 1000. You obtain a value in millisievert per hour (mSv/h).
- Multiply by the time of exposure in hour. You obtain a value in millisievert (mSv).
- Calculate the biological impact of the exposition to the radiation with the chart below.
- We take average value for Tokyo area (line 13) given by Japanese government on March 17th : 0.05 uSv/h.
- We divide by 1000 : 0.05/1000 = 0.00005 mSv/h.
- The time of exposure is 24 hours so we multiply by 24. 0.00005*24 = 0.0012 mSv. If we multiply this value by 365 to compare it with annual values, we obtain : 0.0012*365 = 0.438 mSv.
- Following the chart, the radiation dose received for an annual exposition to this radiation level is equivalent to the one received for an annual exposition to the natural background (~0.48 mSv). There is no need to take any emergency measure.
Please send me your other radiation level sources. Please translate this post into Japanese. Please broadcast!


Body bionics: how the next generation of biosensors could revolutionise drug delivery
Smaller, smarter and more sensitive — how four new technologies could change the way drugs are monitored and administered.
2018 02 28 Kevin Cash Tattoos JDN 8787 NH
The much-heralded 'precision medicine revolution' promises tailored treatments based on individual genetic profiles. But there are other aspects of medicine that could also benefit from a more personalised approach, such as the ability to accurately monitor drug levels and biological molecules inside patients in real time.
In vivo implantable biosensors could allow for this. A variety of biosensors are already in development, promising a broad range of clinical applications. They could, for example, trace inflammation by sensing increased nitric oxide levels or provide individualised pharmacokinetic data for bespoke dosing of antibiotics and cancer drugs. "Imagine the power of being able to have a patient sit in a chair and, as we are infusing the drugs, we will have a [device] that is sensing different drugs and adjusting dosages as a function of the patient's responses," says NetzahualcÃ³yotl Arroyo-CurrÃ¡s, who is in the process of setting up his own sensor group at Johns Hopkins University, Baltimore, Maryland.
Ambitions for such technologies are high, but the development is not quite there yet. Scientists are still working to produce selective, sensitive, reversible and biocompatible sensors.
Biosensors in diabetes care
Perhaps unsurprisingly, the most advanced in vivo sensor systems are already being used for continuous glucose monitoring (CGM). CGM systems have been available on the NHS since 2017 for some people living with type 1 diabetes mellitus — even Theresa May, the UK prime minister, has been photographed wearing one — and trials have found the devices successful in reducing the incidence of hypoglycaemia. The devices use electrochemical sensors that are inserted just under the skin; they work for around 14 days, measuring glucose levels in the interstitial fluid. The sensors use the enzyme glucose oxidase to oxidise glucose, forming hydrogen peroxide which reacts with platinum inside the sensor, generating a concentration-dependent electrical signal that can be sent wirelessly to an associated device, such as a smartphone or other sensor.
The aim for most of the newer real-time glucose monitoring technologies is to find smaller sensors that will work for longer, reducing the need for continuous implantation procedures. One potential avenue of research is exploring optical methods; the first light-based CGM system, EversenseÂ® (Senseonics), was approved by the US Food and Drug Administration in June 2018 and can be worn for 90 days. The sensor is coated with a fluorescent chemical that produces light instead of an electrical signal; the amount of light is measured and reported to a smartphone app.
Biosensors in development
Here are four promising biosensor technologies that are in development.
Ionophore sensors
Kevin Cash, a chemical engineer at the Colorado School of Mines in Golden, Colorado, and colleagues have designed a number of sensors that measure optical or fluorescent signals. Cash started developing optical sensors, known as optodes, in Heather Clark's laboratory at Northeastern University, Boston, Massachusetts. The optical signal is detected simply by photographing the surface of the skin to capture an image of the light produced in vivo. "Basically, you take a picture of it to be able to read out what's going on in the body," explains Cash.
The ionophore-based optical sensors are much smaller than a human hair and each one of these can change colour when the concentration of the drug, or the ion or the metabolite, changes
Clark, a chemical biologist at Northeastern University, and her team have developed a modular family of sensors approximately 100nm in size, enclosed in a biocompatible polymer coating. One of the team's earliest successes in this area was a sensor built in 2013, which tracked histamine levels in vivo using the enzyme diamine oxidase and a phosphorescent oxygen nanosensor. The histamine is broken down by diamine oxidase, causing a reduction in local oxygen levels which, in turn, increases the phosphorescence of the oxygen-sensitive nanosensor[1]
Source: Courtesy of Colorado School of Mines
Kevin Cash, a chemical engineer at the Colorado School of Mines in Golden, Colorado, calls his ionophore-based optical sensors 'nanoparticle tattoos' because they sit in the skin layers
Cash calls his ionophore-based optical sensors 'nanoparticle tattoos' because they sit in the skin layers. "These are much, much smaller than a human hair and we can make each one of these change colour when the concentration of the drug, or the ion or the metabolite, changes," he explains. "We put a bunch of them into a little injection site so its looks like a tiny tattoo, almost — a little circle — and as that changes colour or other optical properties, we can report out what is going on inside the blood stream."
These sensors can detect ions such as lithium, potassium, sodium and calcium — all of which are commonly measured in standard metabolic blood screening. Although the sensors measure the interstitial concentrations of these ions and other small molecules, rather than their concentration in the blood stream, the two values are proportional.
The nanoparticle tattoos are described by Cash as a tiny "squishy, rubber bouncy ball" made from a polymer capsule encasing each sensor. The sensor consists of a pH indicator (chromoionophore), an analyte-specific ligand (ionophore) and a charge-balancing additive. The positively charged ion of interest is pulled into the nanoparticle, causing deprotonation of the pH indicator molecule and a minute colour change which is probably invisible to the naked eye.
The sensor works quickly — the speed at which the image can be captured is the biggest temporal limitation. "For a lot of the work we do, we image once a minute or so, just because otherwise you get too much data," says Cash. "For in vivo imaging, not many things outside of the nervous system change all that fast," he adds.
Carbon nanotube sensors
Another approach is carbon nanotube sensors. Single-walled carbon nanotubes were discovered in 1993 and have unique optical properties. They fluoresce in the near-infrared and do not photo-bleach — meaning they do not lose their ability to fluoresce.
Near-infrared is the perfect spectral range for in vivo work because you can see deeper into tissue
Michael Strano, chemical engineer at Massachusetts Institute of Technology in Cambridge, Massachusetts, and many of his former group members are now independently designing their own carbon nanotube devices, for example, researcher Gili Bisker, who will soon move to Tel Aviv University, Israel. "The wavelengths at which [carbon nanotubes] emit are longer than visible wavelengths, so we cannot see them with the naked eye," says Bisker. "However, this is the perfect spectral range for in vivo work because at this part of the spectrum both blood and water do not absorb much, so you can see deeper into tissue," she adds.
Source: Courtesy of Gili Bisker
Gili Bisker, a researcher who will soon move to Tel Aviv University, Israel, is independently designing her own carbon nanotube sensors
To create the sensor, Strano devised the corona phase molecular recognition (known as 'CoPhMoRe') concept, where the nanotube is wrapped with a functionalised polymer. "The specific conformation that the polymer adopts when it is wrapped around the carbon nanotube is what enables the detection of the analyte of interest, because it forms a unique 3D structure that allows the analyte to bind specifically and selectively to the surface of the nanotube," explains Bisker. From the modulation of the intensity or the wavelength of the fluorescence you can infer the local concentration of the analyte.
As with other optical sensors, the mm-sized device is implanted subcutaneously. It is first encapsulated within a hydrogel that does not disrupt the sensor's responsiveness. The devices have been shown to work successfully in mice for up to 300 days, giving hope for long-term sensing systems that would not need to be constantly replaced. Sensors have been designed to track nitric oxide, providing an indication of inflammation within the body, and other detectable molecules, including insulin, dopamine, L-ascorbic acid, riboflavin, L-thyroxine and oestradiol. Bisker has also investigated detection of larger protein molecules and created a system that can monitor fibrinogen — the protein building block used in blood clots[2]
We are still trying to convince researchers and, in my experience, at least a third of the researchers I run into still think carbon nanotubes are toxic
But one of the major drawbacks with this approach is concern over the toxicity of carbon nanotubes in humans. Questions were first raised over this issue in around 2006, when research indicated that the elongated shape of carbon nanotubes and their hydrophobic nature could trigger similar toxic responses to those caused by asbestos particles when inhaled. Since then, it has been shown that when the nanotubes surfaces are chemically modified this toxicity can be prevented[3]
. "We have shown that our carbon nanotubes sensors [can be made non-toxic] as well," says former Strano group member Nicole Iverson, now at the University of Nebraska–Lincoln. "Right now, we are still trying to convince researchers and, in my experience, at least a third of the researchers I run into still think carbon nanotubes are toxic."
Another


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An appreciation of ethnic jewellery and adornment
Still no actual alphabetic messages have been found on a single artifact excavated from or picked up from the surface of one of the sites of the Bactria-Margiana Archeological Complex. Geographically, the more or less agreed upon boundaries of this area would be Southern Turkmenistan, Eastern Iran and most of Afghanistan reaching over to the Indus Valley in what is now Pakistan. The time frame of the most significant cultural items produced by these migrating farmers and animal domesticators inhabiting the oases and river plains was 4,500 years ago to 3,600 years ago. They did not disappear after this time, but other cultures blended with theirs so thoroughly that the area congealed into a trade system that spread all products far and wide throughout the Middle East, often including parts of Europe, and always including North Africa and the Arabian Gulf.
But in the pre-literate period for the Bactria-Margiana culture -- 4,500 - 3,600 years ago -- the people used seals with meaningful symbols. In the case of stone seals, the images were engraved; in the case of bronze, copper or occasionally silver, the images were cast. The seals were usually furnished with a device that would allow the owner to wear or carry the seal. In fact, so many of the seals were decorated with mythical images that Dr. Sarianidi, the excavator of much of the archeological material, calls them amulets and after long field experience with the amulets, he has interpreted the meanings of the amulets. His work is published in Myths of Ancient Bactria-Margiana on its Seals and Amulets.
One of the more artistic of the seals is the copper image of a wolf killing a goat. The device for hanging the seal on a cord is the loop in the center of the image that shows as a distortion in that area.


text:
INTRODUCTION: Traumatic oesophageal perforation is a rare, life-threatening emergency that requires early recognition and prompt surgical management. PRESENTATION OF CASE: We present an unusual case of a patient on warfarin treatment developed an intramural oesophageal haematoma following blunt thoracic trauma leading to perforation on the 18th day. DISCUSSION: In treatment of oesophageal haematoma in patients on vitamin-K antagonists, strict control of the International Normalized Ratio (INR) is essential along with total parenteral nutrition therapy and refrainment through nasogastric tubes. Three explanations postulated to be the cause for late perforation which might be due to esophageal wall ischemia from pressure built up between the hematoma, azygos vein and the lower part of thoracic trachea; or could be an immediate rupture walled-off until the patient became symptomatic; or the intramural hematoma gradually lysed and causing late perforation. CONCLUSION: Although extremely rare, an oesophageal haematoma and late complications must be considered in patients on anti-coagulant therapy following blunt thoracic trauma and complaining only of chest pain.
International Journal of Surgery Case Reports, 2014, Vol 5, Issue 10, p. 659-61


Preface: I've read this question about water preventing an initiation from occurring.
I understand why it's important to slowly add the alkyl halide to the dry ether and magnesium for exotherm control. But why is the first addition called an initiation and what's its purpose?
Is it just to confirm that the conditions are ready to continue slowly adding the rest of the reagent? I know it's a free-radical reaction, maybe that's where the term "initiation" comes from. But I've seen the reaction described as "self-sustaining" after the initiation, but it's not a chain reaction. Perhaps that's referring to a predictable reaction proceeding forward instead of stalling then blowing up your glassware.
The first step in the Grignard reaction involves transfer of an electron from the surface of the metal to the alkyl halide to form a radical anion. The radical anion then disproportionates into a free radical and halide anion. \begin{aligned} \ce{R−X + Mg &-> R−X^{•−} + Mg^{•+}}\\ \ce{R−X^{•−} &-> R^{•} + X^{−}}\\ \ce{R^{•} + Mg^{•+} &-> RMg^{+}}\\ \ce{RMg^{+} + X^{−} &-> RMgX}\\ \end{aligned}
When you take the magnesium out of the jar, the surface has a thin oxidation layer on it that prevents the initial electron transfer from occurring. We used to take one piece of magnesium and scratch it good with a knife to expose a clean, fresh magnesium surface. We would place this piece of magnesium in the flask (dry ether and the rest of the magnesium already added) and drip in a few drops of the alkyl halide. Without fail, within a minute or two, mild bubbling would be noticed (local ether boiling), which became vigorous as the initiation phase of the reaction "cleaned" the surface of other pieces of oxidized magnesium. After the vigorous bubbling started to subside we would drip in the remaining alkyl halide plus ether solution at a rate to maintain ether reflux. So the reaction does involve a free radical but the initiation phase really has more to do with removing the oxidation layer from all of the magnesium and allowing that initial electron transfer step to occur.
 - $\begingroup$ Good answer, I'd like to add a point to be considered: The initial electron transfer is usually slightly endothermic. In the initiation process you will usually need to add some energy - the warmth of the hand might do (depending on the used halid). After the reaction started, the formation of the Grignard is exotherm, hence providing enough energy to overcome the activation energy of the electron transfer. It will then proceed until the limiting reactant is used up - hence it is called self-sustained. $\endgroup$ – Martin - マーチン Jul 14 '14 at 7:15
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 $\begingroup$ _USER_ That makes a lot of sense. My group has been performing Grignard reagent prep and reactions on and industrial scale, and your answer gives much needed perspective to why we have the initiation step, and how to troubleshoot it if it doesn't go right away. $\endgroup$ – tralston Jul 14 '14 at 15:57
 - $\begingroup$ _USER_ That's an interesting point. Thanks for explaining the self-sustaining aspect of the initation. $\endgroup$ – tralston Jul 14 '14 at 16:05
First, you are mixing magnesium metal with an alkyl halide. The product of this reaction is $\ce{R-Mg-I}$, where $\ce{R}$ is the alkyl group and $\ce{I}$ is the halide. It is called an initiation reaction because you first need to make the reactive compound.
Next, you add the alcohol to produce the product. Mixing an alkyl halide and an alcohol together will not yield the product you want.
Your Answer


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WebMD Medical News
Louise Chang, MD
Dec. 27, 2011 -- Losing yourself in music really may help take the sting out of a root canal or other painful medical procedure -- especially if you are feeling anxious about it.
In a new study, 143 people listened to music while they received a painful shock in their fingertip. Participants were asked to follow the melodies, and identify unusual tones in an effort to take their mind off the pain.
It seemed to do the trick. Participants' pain decreased as they became more and more absorbed in the tunes. Those who were the most anxious reaped the most pain-relieving benefits when they became engaged in the music.
"Our results suggest that engaging activities like music listening may be most effective for reducing pain in high-anxiety persons who can easily become absorbed in activities," conclude researchers led by David H. Bradshaw, PhD, from the University of Utah in Salt Lake City.
The study did not look at different types of music and whether soothing music worked best. Bradshaw says the type of music isn't as important as how well it holds the patient's interest.
The findings appear in The Journal of Pain.
The researchers measured the participants' responses to pain via electrical activity in the brain, dilation of their pupils, and other methods. These are considered more objective than self-reports about pain.
Doctors have understood the power of music for years, commonly using it as a way to distract worried patients.
Roger Fillingim, PhD, says the study shows it may be more effective in people who are overly anxious.
"The concern was that whatever we were doing to help pain will be thwarted by anxiety, but this study suggests that certain types of distraction can actually make anxiety and pain better," says Fillingim, a professor in the College of Dentistry at the University of Florida in Gainesville.
Raffi Tachdjian, MD, MPH, has watched music take children away from their pain through his work at the Children's Music Fund, a nonprofit group that provides musical instruments and music therapy to kids, teens, and young adults with chronic conditions and life-altering illnesses. He is also an assistant clinical professor of medicine and pediatrics at UCLA's David Geffen School of Medicine.
"Music helps show [kids] they can get through it," Tachdjian says. Besides just a simple distraction, music may also have acupuncture-like effects at interrupting pain pathways, he says. "Let's say floor one is your finger, and your brain is the penthouse," he says. "Music helps block the elevator." This way the pain signal can't travel to the brain and cause you to feel and say "ouch."
For those of us who want a little extra help at that next dentist visit, Bradshaw offers this suggestion: "Listening to music with headphones or playing a video game with sound effects that you can listen to with headphones are effective, as the sounds can mask the sound of the dental instruments," he says.
SOURCES:Bradshaw D.H. The Journal of Pain, 2011.Raffi Tachdjian, M.D., MPH, assistant clinical professor of medicine and pediatrics, UCLA's David Geffen School of Medicine, Los Angeles.Roger Fillingim, PhD, associate professor, College of Dentistry, University of Florida, Gainesville.
The Health News section does not provide medical advice, diagnosis or treatment. See additional information.


text: Pakistan's glacial melting woes Published: 2 May 2022 There are more than 6,000 glaciers in northern Pakistan, including Gilgit-Baltistan (GB) and Khyber Pakhtunkhwa (KP). These are clean water reservoirs that actually irrigate Pakistan. But these glaciers are changing rapidly due to climate change. The ecosystem of these areas is changing. Global warming has accelerated their melting and more lakes have been formed as a result. Flooding due to the melting endangers lives and livelihoods of millions of local people and adversely affects the ecology.


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Advanced Rudder Stroke Techniques
The cross bow rudder strokes are similar to the bow rudder strokes. Yet, there is a slight difference. The bow passenger performs this act on the opposite side in which he normally paddles the kayak. The cross bow rudder stroke unlike the bow rudder stroke does not give you the time to switch hands. During this action you must rotate or swivel your body. While in position prepare to swivel your body around toward the opposite direction, and then cross the bow.
At the same time you want to scoop the blade downward toward the water. To avoid ensnaring your hand between the gunwale and blade, make sure you bring the lower hand up, and place it on the shank (shaft) a few inches. Keep the paddle gripped near the armpit (left) and make sure the paddle's blade dips into the water at a 40 degree angle.
Tip: You can use the sweep strokes at a 90-degree angle and reach the same affect you would get from the cross bow rudder method. Sweep strokes are commonly used by kayakers and canoeists to turn the boat slightly without interrupted the direction.
How sweep strokes work? You have choice. The first choice is to push over the bow. The second choice is to drive the kayak forward. The third method is to pull the stern toward the paddle.
How do other types of kayaking strokes work? Well, it depends on the stroke in which many are employed in kayaking. For instance, the stern rudder stroke is similar to the bow rudder strokes. The bow rudder is the process where the bow passenger uses his paddles to steer the boat in the course which he is paddling the kayak. The stern stroke is often utilized when the stern passenger cannot use the J-stroke method to redirect his kayak. Sometimes the direction the kayak is headed needs readjustment, thus the kayaker will employ the stern stroke to redirect the boat. Unlike the bow rudder stroke the person paddling the kayak will reverse his sweep and take a 120-degree angled turn rather than a 40-degree turn.
Tip: If you need to make an immediate turn while kayaking the bow rudder strokes is ideal, yet a draw stroke would be more beneficial if you spotted a obstacle in the waters that could cause damage. The bow rudder strokes will slow the kayak.
Kayaks are sport canoes, which are often lightweight and made of fiberglass. The boats are utilized in whitewater rafting, leisure, and often in competitive sports. The older models were made of animal skin, which *Inuit boats held one or two passengers, which both would use double-blade paddles to control the kayak. Sometimes people use kayaks to travel or race.
Facts: *Inuit is Artic people, or people from Greenland. The members of these lands lived in coastal areas of the Artic, Greenland, and Canada. The languages of Inuit descendants constituted languages of three branches. The branches included the Eskimo Aleut family.
Canoeing has dated back for centuries, which the kayak is a form of canoe. Today, people are enjoying whitewater kayaking, traveling, cruising, and more. In fact, the Internet has posted many sites that offer vacations that include whitewater kayaking. Kayaks are far more dangerous than canoes, since kayaks have closed seating arrangements, which you are often strapped in with knee and thigh straps. If you capsize (flip) the kayak, you had better learn steps to take to save your life.


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BC takes a meaningful step forward on its commitment to implement UNDRIP with the introduction of the Declaration Act (Bill 41)
On October 24, 2019, the BC Government introduced Bill 41 – Declaration on the Rights of Indigenous Peoples Act (the Declaration Act), which passed First Reading on the same day. This legislation, if passed, will mandate the Government to align provincial laws with the United Nations Declaration on the Rights of Indigenous Peoples (UNDRIP or the Declaration) and will form the foundation for the Province's work on reconciliation. The Declaration Act follows upon the Government's commitment to make BC the first province in Canada to introduce legislation to implement UNDRIP, in co-development with the First Nations Leadership Council and other Indigenous organizations, as indicated in its 2019 Throne Speech. The BC NDP's commitment to adopting UNDRIP was also a focus of its 2017 election campaign and formed a "foundational piece" of its 2017 Confidence and Supply Agreement with the BC Green Party caucus.
In the first of two news releases announcing the proposed Act, entitled "Indigenous human rights recognized in B.C. law with new legislation", the Province highlights the legislation's forward-looking approach towards reconciliation and upholding human rights, as well as the collaborative work that was undertaken with Indigenous peoples in developing the legislation.
The second news release, entitled "Reconciliation legislation fosters greater economic certainty", states that the Declaration Act, if passed, will "move the Province forward with a clear action plan for reconciliation, supporting predictability and economic opportunities" and will "create greater transparency and predictability in its work together with Indigenous peoples." The Province also states that the legislation aims to create further certainty for investment and opportunities for business while creating a strong inclusive economy.
Key Provisions of the Declaration Act
The three stated purposes of the Declaration Act are to (a) affirm the application of UNDRIP to the laws of BC; (b) contribute to the implementation of UNDRIP; and (c) support the affirmation of, and develop relationships with, Indigenous governing bodies.
A brief piece of legislation, the Declaration Act provides that:
- In consultation and cooperation with Indigenous peoples, the government "must take all measures necessary to ensure the laws of BC are consistent with the Declaration" (s. 3 – Measures to align laws with Declaration)
- The government "must prepare and implement an action plan to achieve the objectives of the Declaration" (s. 4 – Action Plan), and must prepare an annual report outlining its progress in implementing the action plan (s. 5 – Annual Report)
- The Act gives authority for the government, for the purposes of reconciliation, to enter into agreements with Indigenous governing bodies in relation to the exercise of a statutory power of decision (s. 6 – Agreements & s. 7 – Decision-making agreements)
- The government can also make regulations under the Act (s. 9 – Power to make regulations).
What does it mean for government to "take all measures necessary" to ensure laws are "consistent" with UNDRIP?
The language used in section 3 of the Declaration Act raises important questions as to how the Province's success at implementing UNDRIP will be measured. First, the requirement to "take all measures necessary" is extremely broad and the Declaration Act does not clarify what measures would be considered sufficient to achieve the requirement of consistency of laws with UNDRIP. It imposes an arduous standard by lacking a 'reasonableness' component or other flexibility. This could potentially set up the government for failure and legal challenges with regard to the adequacy of its efforts at implementation. Second, the requirement for laws to be "consistent with" UNDRIP is not further described or defined. The proposed legislation does not set out any parameters for determining when and whether this requirement for "consistency" has been achieved, or by what and by whose standard.
Notably, other than substituting "British Columbia" for "Canada", the language in section 3 of the Declaration Act is identical to the language in section 4 – Consistency of the federal Bill C-262. Bill C-262 sought to harmonize federal laws with UNDRIP but failed to pass the Senate in June 2019, mainly as a result of concerns over perceived deficiencies and uncertainties with its drafting, including with the potential unintended consequences of this broad language. We expect that similar questions will be raised as Bill 41 makes its way through the legislative process. (We note that the federal Liberal government has indicated that it intends to reintroduce similar legislation).
To some extent, the Province's intentions with section 3 can be surmised from certain statements in its news releases introducing Bill 41, including that "[o]ver time, as provincial laws are modified or built, they will be aligned with" UNDRIP, and that "[e]xisting B.C. laws will not change immediately – bringing provincial laws into alignment with the UN Declaration will take time and will require consultation with Indigenous peoples and stakeholders including business, industry and local government." While these comments do not resolve the issues of interpretation noted above, these statements suggest that progress towards implementing UNDRIP is intended to be incremental rather than immediate, and that current laws should not be deemed invalid if they are presently "inconsistent" with UNDRIP.
What is the significance of Agreements under the Declaration Act?
Bill 41 introduces the concept of agreements with Indigenous governing bodies as tools to achieve reconciliation and to fulfill the purposes of the Act. Section 6 – Agreements and section 7 – Decision-making agreements provide that the Lieutenant Governor in Council may authorize a member of the Executive Council, on behalf of the government, to negotiate and/or enter into an agreement with an Indigenous governing body, for the purposes of reconciliation, relating to one or both of:
- a statutory power of decision jointly by (i) the Indigenous governing body and (ii) the government or another decision maker
- the consent of the Indigenous governing body before the exercise of a statutory power of decision.
A "statutory power of decision" (as defined in the Judicial Review Procedure Act, RSBC 1996, c 241) is a power or right conferred by statute "to make a decision deciding or prescribing (a) the legal rights, powers, privileges, immunities, duties or liabilities of a person, or (b) the eligibility of a person to receive, or to continue to receive, a benefit or licence, whether or not the person is legally entitled to it, and includes the powers of the Provincial Court."
The legislative intent of the agreements appears to be to provide a tool or mechanism for the government to work together with Indigenous groups on decision-making processes on matters that will affect them. This includes express contemplation of a negotiated consent requirement prior to a government decision. Theoretically, the subject matter of such agreements and their application under other statutes could be very broad. The only parameters appear to be that agreements are to be used "for the purposes of reconciliation" and must relate to statutory decisions that fall within the definition of "statutory power of decision" (e.g. decisions that will affect the rights and interests of Indigenous peoples).
Despite the potentially broad subject matter of the agreements, it is important to note that the entry into such agreements is discretionary. The Government explains that Bill 41 provides for discretion for new decision-making agreements between the Province and Indigenous governments "where decisions directly affect Indigenous peoples and mechanisms exist in applicable legislation – with clear processes, administrative fairness and transparency." Further, the Province promotes the Declaration Act as a means of "supporting predictability and economic outcomes", and "further certainty for investment". Therefore it appears that the current government will want to use such agreements strategically, taking care to avoid undue disruption of current regulatory regimes. Notably, the new BC Environmental Assessment Act under Bill 51 (not yet in force), also contains provisions to enable government to enter into agreements with Indigenous nations for the purposes of conducting any aspect of an EA.
The Government acknowledges that Bill 41 is intended to carve out recognition for additional forms of Indigenous governments, including multiple Nations working together as a collective, as well as hereditary governments "as determined and recognized by the citizens of the Nation." It states that this will "provide more clarity for businesses and communities about who to engage when working with Indigenous partners."
To support transparency, Bill 41 sets out a process whereby once negotiations are authorized, the government must publish a summary of who will be consulted before or during the negotiation and entry into agreements. Agreements reached under the Declaration Act would be also required to be made public and published in the Gazette.
What is the effect on the interpretation of free, prior and informed consent?
The concept of free, prior and informed consent (FPIC) is a prominent feature of UNDRIP, referenced in Articles 10, 11(2), 19, 28(1), 29(2) and 32(2) in respect of various situations, including the requirement to obtain the FPIC of Indigenous groups prior to approving projects affecting Indigenous lands or territories, and in developing legislation that will affect Indigenous groups.
Bill 41 does not refer to the concept of FPIC and the Province has yet to define FPIC in any other piece of legislation. However, in the rollout of the new BC Environmental Assessment Act (not yet in force), the Province has made considerable efforts to articulate its position on FPIC in the context of environmental assessments. For example, it explains:
"Obtaining [FPIC] is an integral aspect of [UNDRIP]. The new EA process is designed to ensure that any decision taken on the question of consent by an Indigenous nation is free, prior and informed. Respectful of their own Indigenous laws, traditions and right of self-determination, a key objective of the new


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About Army ROTC
The Army Reserve Officers' Training Corps (ROTC), as it exists today, began with President Wilson signing the National Defense Act of 1916. Although military training had been taking place in civilian colleges and universities as early as 1819, the signing of the National Defense Act brought this training under a single, federally-controlled entity: The Reserve Officers' Training Corps.
Army ROTC is the largest officer-producing organization with the American military, having commissioned more than half a million second lieutenants since its inception.
Women have been an integral part of the Army ROTC since 1972. The first group of females from ROTC were commissioned in 1975. Today, women constitute 20 percent of the Corps of Cadets and more that 15 percent of each commissioning cohort.
In April 1986, the U.S. Army Cadet Command was formed. With its headquarters in Fort Monroe, Virginia, Cadet Command assumed responsibility for more than 400 senior ROTC units, four regional headquarters and the Junior ROTC with programs in more than 800 high schools. Cadet Command transformed the ROTC from a decentralized organization turning out a heterogeneous group of junior officers into a centralized command producing lieutenants of high and uniform quality. An improved command and control apparatus, an intensification and standardization of training and improvements in leadership assessment and development helped produce this transformation of pre-commissioning preparation.
Today, Army ROTC has a total of 272 programs located at colleges and universities throughout the 50 states, the District of Columbia and Puerto Rico with an enrollment of more than 20,000. It produces approximately 60 percent of the second lieutenants who join the active Army, the Army National Guard and the U.S. Army Reserve. More than 40 percent of current active duty Army General Officers were commissioned through the ROTC. Of even greater importance is that ROTC trained and educated officers bring a hybrid vigor to our officer corps by drawing on the strength and variety of our social fabric. This reduces the natural tendency of armies to drift into inbred professional separatism. Cadet Command accomplishes this by combining the character building aspects of a diverse, self-disciplined civilian education with tough, centralized leader development training. This process forges a broad-gauged officer who manifests the strength and diversity of the society from which he or she is drawn as well as the quality of strong officer leadership.


= 3.9mm
 - Pitch circle diameter (Pc) = m*z = 10*18 = 180mm
 Hole depth = 2.25*m = 2.25*10 = 22.5mm
 - Thickness of the tooth = 1.571*10 = 15.71mm
 Face width (b) = 0.3*180= 54mm
 - Center distance between two gears = 180mm
 - Diametral pitch = Number of teeth/P.C.D= 18/180= 0.1mm
 A static structural analysis were done to analyse the behavior of the structure under the steady loading conditions while ignoring inertia and damping effects, such as those carried by time varying loads. All types of non-linearity are allowed such as large deformations, plasticity, creep, stress stiffening, contact lements etc. this result will determined whether the structure will withstand for the applied external loads..
 If the stress values obtained in this analysis crosses the allowable values it will result in the failure of the structure in the static condition itself. To avoid such a failure, this analysis is necessary. In this project the FEA based analysis tool were used to study the structural behaviour of the different composite material under the given boundary conditions by determining the total deformation.
 Al(90%)-Ti(10%)-LOAD 12000N
 Fig 4.1- Deformation
 Fig 4.2- Stress
 Al(90%)-Ti(10%)-LOAD 15000N
 Fig 4.3- Deformation
 Fig 4.4- Stress
 MATERI ALS
 LOAD 12000N
 LOAD 15000N
 Al(90%)- Ti(10%)
 Deformation( mm)
 The stir casting is mostly used to produce the PRMMCs because it shown to be a very promising for the manufacture of near net shape composites in a simple and cost effective manner. Firstly the metal matrix composition is to be added and then the stirrer is switched on. The stirring speed can be variable, the constant speed for all metal matrix composite is around 600-800 m/s.The materials are added in powder or particulate or viscous form. In this project powder form of Aluminium and Titanium ingots are added. For attaining the wettability of the material borax powder is added. The amount of addition is for every gram 2-3% is added. The Aluminium and Titanium are added in the ratio of 90:10.
 Apart from other casting methods, stir casting overcomes difficulties of other casting methods. The molten solution is then checked for any large particles of Titanium in Aluminium or it is fully dissolved in the solution. After that the material is poured into the pattern that is made in the mould.Then depending upon the solidification time of the material used, the mould is left for some time to solidify. Then the solid material is taken off the mould and is machined. In this project the specimen preparation is done for hardness, impact, tensile tests. The casted material is machined as per the standards for particular tests.
 The mechanical test can be conducted by the following parameters.To know about the material elongation,strength,hardness,withstand load capacity.
 - Tensile Test
 - Impact Test
 MATERIAL S
 TENSILE TEST
 IMPACT TEST
 Ultimate Tensile load(KN)
 Ultimate Tensile strength(N/m m2)
 Al(90%)and Ti(10%)
 MATERIAL S
 TENSILE TEST
 IMPACT TEST
 Ultimate Tensile load(KN)
 Ultimate Tensile strength(N/m m2)
 Al(90%)and Ti(10%)
 - Brinell hardness Test
 4. ADVANTAGES:
 - Composites are light in weight when compared with most metals
 - Composite gear can be design to both strong and
 light weight.Hence It has more Strength to weight ratio when compared with other metals
 - Composite gear can be more harder than other metals
 - Composite material can be molded into complicated shape more easily than other metals
 - Composites resists damage from whether
 - Composite gear can have less porosity
 - Automobile gear boxes
 - Metal cuing machines
 - Gear motors and Gear pumps
 - Rack and Pinion mechanism
 - Material handling equipment
 - Steel mills
 - Rolling mills
 - Washing machines
 In this project Aluminium Titanium metal matrix composite material is suggested for the manufacture of spur gears. The MMC is prepared and tested by both mechanically and analytically. The results show that this MMC has properties that can replace the existing material that is used conventionally. Thus providing less weight,more life and withstand more load than conventional gears.It has better strength to weight ratio,better hardness than conventional gears.These gears can be able to transmit up to 40kW power. These gears can be used in automobiles and other machinery where spur gears find an application.
 1. S Rajeshkumar and R Manoharan, Design and analysis of composite spur gears using finite element method, IOP Conf.
 Series: Materials Science and Engineering 263 (2017) 062048
 2. Mrs.S.Kousalya Devi S,Finite element analysis of composite spur gear,IJRDO-Journal of Mechanical And Civil Engineering ISSN: 2456-1479, Volume-3 | Issue-1 | January,2017
 3. M. Keerthi, K. Sandya, K. Srinivas, Static & Dynamic Analysis of Spur Gear using Different Materials,International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395- 0056 Volume: 03 Issue: 01 | Jan-2016
 4. Utkarsh.M.Desai, Prof.Dhaval.A.Patel,Modeling and stress analysis of composite material for spur gear under static loading condition International journal of advances in production and mechanical engineering,VOLUME1,ISSUE2,2015
 5. T. Albert*, C. Pravin Tamil Selvan,Preparation and Properties of Aluminium composite,International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2277-9655
 6. Chhabra Pankaj, Bhatia Amit, Design and Analysis of Composite Material Gear Box, International Journal of Mechanical and Civil Engineering, Vol.1 (2012), Issue1,pp 15- 25.
 7. Lijesh K.P. and Harish Hirani, Probabilistic Design of Spur Gear,International Journal of Current Engineering and Technology E-ISSN 2277 4106
 8. El-Sayed S. Aziz*, Constantin Chassapis,Probabilistic Simulation Approach to Evaluate the Tooth-Root Strength of Spur Gears with FEM-Based Verification,Scientific research,
 Engineering, 2011, 3, _PHONE_
 9. R.M. Mohanty, K. Balasubramanian, S.K. Seshadri, Boron carbide-reinforced aluminium 1100 matrix composites: fabrication and properties, Materials science and engineering, 498(2008), p 42-52
 10. Ali Raad Hassan, Contact Stress Analysis of Spur Gear Teeth Pair WASET 58, 2009.
 11. V.B.Bhandari,Design of Machine Elements, 3rd Edition, Tata McGraw Hill Publication,(2013) pp-646-690.
 12. Hashim J.,Looney L Hashmi M.S.J., Metal Matrix Composites: Production by the Stir Casting Method, Journal of Material Processing and Technology,(1999),pp. 17.
 13. VI. PSG Design Data Book, PSG College of Technology Coimbatore, 1966, pp 8.1-8.64
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