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TO CONDITION, OR NOT TO CONDITION, THAT IS THE QUESTION
Between the completely conditional world of Bayesian inference and the completely unconditional world of frequentist inference lies the hazy world of conditional inference.
The extremes are easy. In Bayesian-land you condition on all of the data. In Frequentist-land, you condition on nothing. If your feet are firmly planted in either of these idyllic places, read no further! Because, conditional inference is:
The undiscovered Country, from whose bourn
No Traveller returns, Puzzles the will,
And makes us rather bear those ills we have,
Than fly to others that we know not of.
1. The Extremes
As I said above, the extremes are easy. Let's start with a concrete example. Let be a sample from. Suppose we want to estimate ; for example, could be the mean of.
Bayesian Approach: Put a prior on. After observing the data compute the posterior for. This induces a posterior for given. We can then make statements like
The statements are conditional on. There is no question about what to condition on; we condition on all the data.
Frequentist Approach: Construct a set. We require that
where is the distribution corresponding to taking samples from. We the call a confidence set. No conditioning takes place. (Of course, we might want more than just the guarantee in the above equation, like some sort of optimality; but let's not worry about that here.)
(I notice that Andrew often says that frequentists "condition on ". I think he means, they do calculations for each fixed. At the risk of being pedantic, this is not conditioning. To condition on requires that be a random variable which it is in the Bayesian framework but it is not a random variable in the frequentist framework. But I am probably just nit picking here.)
2. So Why Condition?
Suppose you are taking the frequentist route. Why would you be enticed to condition? Consider the following example from Berger and Wolpert (1988).
I write down a real number. I then generate two random variables as follows:
where and and iid and
Let denote the distribution of. The set of distributions is.
I show Fred the frequentist and and he has to infer. Fred comes up with the following confidence set:
Now, it is easy to check that, no matter what value takes, we have that
Fred is happy. is a 75 percent confidence interval.
To be clear: if I play this game with Fred every day, and I use a different value of every day, we will find that Fred traps the true value 75 percent of the time.
Now suppose the data are. Fred reports that his 75 percent confidence interval is. Fred is correct that his procedure has 75 percent coverage. But in this case, many people are troubled by reporting that is a 75 percent confidence interval. Because with these data, we know that must be 18. Indeed, if we did a Bayesian analysis with a prior that puts positive density on each, he would find that.
So, we are 100 percent certain that and yet we are reporting as a 75 percent confidence interval.
There is nothing wrong with the confidence interval. It is a procedure, and the procedure comes with a frequency guarantee: it will trap the truth 75 percent of the time. It does not agree with our degrees of belief but no one said it should.
And yet Fred thinks he can retain his frequentist credentials and still do something which intuitively feels better. This is where conditioning comes in.
The statistic is an ancillary: it has a distribution that does not depend on. In particular, for every. The idea now is to report confidence, conditional on. Our new procedure is:
If report with confidence level 1.
If report with confidence level 1/2.
This is indeed a valid conditional confidence interval. Again, imagine we play the game over a long sequence of trials. On the subsequence for which, our interval contains the true value 100 percent of the time. On the subsequence for which, our interval contains the true value 50 percent of the time.
We still have valid coverage and a more intuitive confidence interval. Our result is identical the Bayesian answer if the Bayesian uses a flat prior. It is nearly equal to the Bayesian answer if the Bayesian uses a proper but very flat prior.
(This is an example where the Bayesian has the upper hand. I've had other examples on this blog where the frequentist does better than the Bayesian. To readers who attach themselves to either camp: remember, there is plenty of ammunition in terms of counterexamples on BOTH sides.)
Another famous example is from Cox (1958). Here is a modified version of that example. I flip a coin. If the coin is HEADS I give Fred. If the coin is TAILS I give Fred where. What should Fred's confidence interval for be?
We can condition on the coin, and report the usual confidence interval corresponding to the appropriate Normal distribution. But if we look unconditionally, over replications of the whole experiment, and minimize the expected length of the interval, you get an interval that has coverage less than for HEADS and greater than for TAILS. So optimizing unconditionally pulls us away from what seems to be the correct conditional answer.
3. The Problem With Conditioning
There are lots of simple examples like the ones above where, psychologically, it just feels right to condition on something. But simple intuition is misleading. We would still be using Newtonian physics if we went by our gut feelings.
In complex situations, it is far from obvious if we should condition or what we should condition on. Let me review a simplified version of Larry Brown's (1990) example that I discussed here. You observe
, and each is a vector of length. Suppose further that the covariates are independent. We want to estimate.
The "best" estimator (the maximum likelihood estimator) is obtained by conditioning on all the data. This means we should estimate the vector by least squares. But, the least squares estimator is useless when.
From the Bayesian point of view we compute we compute the posterior
which, for such a large, will be useless (completely dominated by the prior).
These estimators have terrible behavior compared to the following "anti-conditioning" estimator. Throw away all the covariates except the first one. Now do linear regression using only and the first covariate. The resulting estimator is then tightly concentrated around with high probability. In this example, throwing away data is much better than conditioning on the data. There are some papers on "forgetful Bayesian inference" where one conditions on only part of the data. This is fine but then we are back the the original question: what do we condition on?
There are many other example such as this one.
4. The Answer
It would be nice if there was a clear answer such as "you should always condition" or "you should never condition." But there isn't. Do a Google Scholar search on conditional inference and you will find an enormous literature. What started as a simple, compelling idea evolved into a complex research area. Much of these conditional methods are very sophisticated and rely on second order asymptotics. But it is rare to see anyone use conditional inference in complex problems, with the exception of Bayesian inference which some will argue goes for a definite, psychologically satisfying answer at the expense of thinking hard about the properties of the resulting procedures.
Unconditional inference is simple and avoids disasters. The cost is that we can sometimes get psychologically unsatisfying answers. Conditional inference yields more psychologically satisfying answers but can lead to procedures with disastrous behavior.
There is no substitute for thinking. Be skeptical of easy answers.
Thus Conscience does make Cowards of us all,
And thus the Native hue of Resolution
Is sicklied o'er, with the pale cast of Thought,
Berger, J.O. and Wolpert, R.L. (1988). The likelihood principle, IMS.
Brown, L. D. (1990). An Ancillarity Paradox Which Appears in Multiple Linear Regression. Ann. Statist. 18, 471-493. link to paper.
Cox, D.R. (1958). Some problems connected with statistical inference. The Annals of Mathematical Statistics, 29, 357-372.
Please comment on the article here: Normal Deviate


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Chicago (CNN) - New data from the U.S. Census Bureau shows more people are moving downtown.
The report defined downtowns as within a two-mile radius of a city hall, and the 2010 census shows 16 million people were living downtown. That's about six percent of the 258 million metro-area dwellers.
Chicago saw the biggest downtown population boom, which saw 48,000 new residents over 10 years.
New Orleans saw the largest decline, losing 35,000 people from 2000 until 2010.
Researchers believe the move is due to people wanting to live closer to their jobs.

source: HuggingFaceFW/fineweb-edu


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Plain Language Summaries
Plain Language Summaries aim to summarise research papers in a way that is accessible to a wider audience.
PLS 1 – What is the effect of unemployment on mortality? (SLS)
- Previous research has demonstrated a link between unemployment and an increase in death rates.
- The aim of this study was to test whether it is unemployment itself or other factors which cause this rise in mortality, such as poor health or low socio-economic status.
- Background information on around 3,260 Scottish people was gathered from the 1991 and 2001 censuses. All of them were in employment in 1991, but half of the group were no longer in work at 2001.
- The results found strong evidence of a direct link between unemployment and subsequent death rates in men.
PLS 2 – Do people who move to large cities progress faster in their career? (ONS LS)
- 'Escalator' regions are places people move to get ahead more quickly in their career.
- In England, London is the main escalator region, and there are fears that this leads to other large cities losing out on the most highly-skilled workers.
- This research used the ONS LS to compare working age people at the 1991 and 2001 Censuses who were living in London or one of the next 9 largest English cities.
- For people who stayed in the same city during the decade, those living in London were 30% more likely to have advanced in their career than those in the other cities. Manchester was the only other city to show a similar effect, though it did so at a much lesser level.
- People who moved during the decade experienced a similar 'escalator' effect regardless of whether they moved to London or one of the other cities, and were more likely to have been promoted than people who did not move.
PLS 3 – Mortality among immigrants in England & Wales by major cause of death (ONS LS)
- Previous studies have found that people who move to a new country tend to have lower death rates than the native population there. But it is also known that people from different countries can have higher risk of specific diseases, e.g., people from South Asia have higher genetic risk of developing cardiovascular disease (CVD)
- By using a large sample from the ONS LS and looking at cause of death over a 40 year period from _PHONE_, the authors were able to look more closely at the risks for different immigrant groups
- The results show that the overall pattern of lower mortality for migrants hides a more complicated picture, with some populations at higher risk of death from specific types of disease
- These findings are important because they show that health risks vary among different groups of immigrants in the population
- Public health campaigns may need to be targeted more carefully to reach specific at-risk groups

source: openbmb/Ultra-FineWeb


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U.S. Department of Energy - Energy Efficiency and Renewable Energy
Fuel Cell Technologies Office – Safety, Codes & Standards
Current Approaches to Safety, Codes and Standards
Current approaches to hydrogen and fuel cells safety, codes and standards are based on existing practices, guidelines, and codes and standards developed as a result of hydrogen's use in the chemical and aerospace industries.
While some codes and standards for hydrogen and hydrogen-related systems are already available, in many cases they do not fully address the new issues that arise when considering the needs of a future clean energy economy. DOE is coordinating the efforts of codes and standards organizations to identify and address the gaps, clarify and consolidate regulations, validate outdated test results, and ultimately develop new, more appropriate codes and standards that will ensure the safe use of hydrogen in the future.
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The victimisation rate is defined as the total number of victims of a crime in a given population expressed as a percentage of that population.
A victim may be a person or a household reporting at least one of the crimes surveyed. Victims were counted once only for each type of crime, regardless of the number of incidents of that type.
These statistics are derived from information collected in the ABS Multipurpose Household Survey.
The Survey covered only selected types of personal and household crimes. Personal crimes included physical assault, threatened assault, robbery and sexual assault. Household crimes included break-ins, attempted break-ins, motor vehicle theft, theft from a motor vehicle, malicious property damage and other theft.
Information collected in the Survey was 'as reported' by respondents and hence may differ from that which might be obtained from other sources or via other methodologies.
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Jpn J Ophthalmol. 2007 Sep-Oct;51(5):347-52. Epub 2007 Oct 5.
Changes in contrast sensitivity function and ocular higher order aberration by conventional myopic photorefractive keratectomy.
Author information
 - 1Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan.
To evaluate the relation between induced changes in ocular higher order aberrations and changes in the contrast sensitivity function in patients undergoing excimer laser photorefractive keratectomy (PRK).
Myopic PRK using excimer laser was performed in 31 patients (56 eyes). The preoperative refractive error was -6.2 +/- 2.9 diopters. Before and 1 month after surgery, we measured the ocular higher order aberrations for a 4-mm pupil, and three indices of contrast sensitivity function. From the data collected, the area under the log contrast sensitivity function (AULCSF) was calculated.
PRK significantly reduced AULCSF (P = 0.004), low-contrast visual acuity (P = 0.004), and letter-contrast sensitivity (P = 0.013). Coma-like (P < 0.001) and spherical-like (P < 0.001) aberrations were significantly increased by surgery. The change in AULCSF by surgery significantly correlated with the change in coma-like (r = -0.468, P < 0.001) and spherical-like (r = -0.291, P = 0.033) aberrations. The change in low-contrast visual acuity by PRK significantly correlated with the change in coma-like aberration (r = 0.599, P < 0.007), but not with change in spherical-like aberrations (r = 0.136, P = 0.326). There were significant correlations between changes in letter-contrast sensitivity and changes in coma-like (r = -0.450, P < 0.001) and spherical-like (r = -0.255, P = 0.048) aberrations.
PRK significantly increases ocular higher order aberrations, which compromise contrast sensitivity function after surgery.
[PubMed - indexed for MEDLINE]
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The Bigfoot Evidence blog recently posted an entry entitled "Yes, Bigfoot Can Swim: Scientists Prove That Apes Can Swim and Dive." The entry highlights a recent Science Daily article about a chimpanzee and an orangutan with the ability to swim and dive underwater, the first such behavior described for apes. I'm amazed that this is being offered up as evidence that Bigfoot can swim. This is wrong for at least three reasons. First, there is no way to verify reports of swimming Bigfoots. Other than unreliable eyewitness accounts–often passed on in the form of hearsay by those who did not see the creature–there is no video or photographic evidence of any kind to support the stories. Some people may believe they are telling the truth, but errors, such as misidentifying a known animal (e.g. bears), cannot be ruled out (nor can hoaxing). The folklorist Kathrine Briggs makes a distinction between fairy tales, which are believed to be fictional, and folk tales, which are believed to be true. And since the latter contains uncorroborated elements, reports of swimming Bigfoots are no more credible than legends of giants, fairies, ghosts, and witches that were once commonly circulated–essentially making them modern folklore. They would never be accepted as evidence in a court of law, nor could they pass for scientific evidence.
Second, the swimming of the aforementioned apes is human-induced behavior. The original study, "Brief communication: Swimming and diving behavior in apes (Pan troglodytes and Pongo pygmaeus): First documented report," mentions how the chimp Cooper and the orangutan Suryia were both raised by humans in a home and in a private zoo, respectively. Both were exposed to water from a young age: first through baths and later during supervised playtime in the shallow end of pools. Although this study invalidates the long held idea that apes can't swim due to their dense anatomy, there is clearly an environmental factor at play that keeps these creatures from swimming in the wild (see below). Cooper and Suryia would not have developed these skills without the encouragement of their human parents/keepers. Therefore, it should be stressed that their abilities are unique among apes the world over. This means the study is nothing more than a scientific anecdote. As the primatologist William C. McGrew points out: "All that an anecdote can do is alert us to a possibility, so that we will look for it again." In addition, he warns that "citing specific events as evidence for something broader [can lead] to overgeneralization." This leads me to my last point.
A video of Suryia the Orangutan swimming.
Third and most importantly, wild and captive apes typically shun large bodies of water. The aforementioned study mentions that the scientific literature "indicate[s] that apes' behavior towards water bodies in the wild might be adaptive—they avoid deep water bodies and are extremely cautious when entering even shallow water." The authors suggest this hydrophobia is a survival strategy since apes probably lost the instinctual swimming ability that most terrestrial mammals have because they spend most of their lives in or near trees. This explains why apes have never been observed drowning in the wild. Captive apes, on the other hand, often drown in the moats that zoos use to keep them confined to their outdoor habitats. This is because they have more exposure to bodies of water than they do in the wild. Dr. Roger Fouts somberly describes a captive drowning in his wonderful book Next of Kin: My Conversation With Chimpanzees (1997):
One morning I couldn't find Candy and I became worried that she had attempted to jump the moat and had drowned. My students and I waded into the water up to our chests and began dredging the muddy bottom with poles. After an hour or so, I felt her small body under my feet, and went down to retrieve it. As I emerged from the moat, cradling Candy's lifeless body in my arms, the other chimps kept their distance…I had never seen, much less held, a dead chimpanzee before. It was heartbreaking. Chimpanzees, like human children, are so animated in every expression, so vibrant in every leap, that their spirit seems like the very essence of life itself. Drained of Candy's spirit, the stiff body I held was just an empty vessel.
So, in the end, this attempt to support modern folklore with an unrelated scientific anecdote further relegates Bigfootology to the realm of pseudoscience. Proponents of cryptozoology are often accused of not being objective enough, and this serves as a prime example of this. They focus on all the evidence that they feel supports their views–even going so far as to twist data to fit like above–while ignoring all that invalidates them.
 See the section on "Misidentification Errors" in Daniel Loxton and Donald R. Prothero, Abominable Science!: Origins of the Yeti, Nessie, and Other Famous Cryptids (New York: Columbia University Press, 2013), 56-59. A 2009 study found Bigfoot and Black Bears (Ursus americanus) (un)coincidentally share the same territory. See ibid, 57.
 Katharine M. Briggs, A Dictionary of British Folk-Tales in the English Language: Part B : Folk Legends : Vol. 1 (London: Routledge & Kegan, 1971), vii-viii.
 William Clement McGrew, The Cultured Chimpanzee: Reflections on Cultural Primatology (Cambridge [u.a.]: Cambridge University Press, 2004), 79.
 Ibid, 175-176.
 Roger Fouts, Next of Kin: My Conversations With Chimpanzees (New York: Bard Books Inc, 1997), 179.
 See for example Loxton and Prothero, 65-66.
Briggs, Katharine M. A Dictionary of British Folk-Tales in the English Language: Part B : Folk Legends : Vol. 1. London: Routledge & Kegan, 1971.
Fouts, Roger. Next of Kin: My Conversations With Chimpanzees. New York: Bard Books Inc, 1997.
Loxton, Daniel, and Donald R. Prothero. Abominable Science!: Origins of the Yeti, Nessie, and Other Famous Cryptids. New York: Columbia University Press, 2013.
McGrew, William Clement. The Cultured Chimpanzee: Reflections on Cultural Primatology. Cambridge [u.a.]: Cambridge University Press, 2004.


Quick Answer: Does Saltwater Freeze?
Why does salt water not freeze?
Does salt water freeze colder?
When water freezes from being in cold air, the release of heat actually slows down the freezing. When you add salt to a mixture of water and ice, it causes more ice to melt by depressing the freezing point and not by adding internal energy so it actually gets colder.
Does water with salt freeze faster?
At what temp does saltwater freeze?
about 28.4 degrees FahrenheitOcean water freezes at a lower temperature than freshwater. Fresh water freezes at 32 degrees Fahrenheit but seawater freezes at about 28.4 degrees Fahrenheit, because of the salt in it. When seawater freezes, however, the ice contains very little salt because only the water part freezes.
What temp does salt water pool freeze?
28 degreesYes, although their freeze point is just a bit lower than regular chlorinated water. Salt water pools freeze usually freeze closer to 28 degrees as opposed to 32, but nonetheless, they still freeze. So, treat it just like any other pool.
How long does it take for salt water to freeze?
approximately four hoursThe freezing point for sea water is lower than it is for fresh water–which freezes at 32 degrees Fahrenheit–because of its greater density. 500 ml of saltwater (containing 1 tsp of salt) will take approximately four hours to freeze in a home freezer.
Why is the freezing point of salt water lower?
Ice in contact with salty water therefore melts, creating more liquid water, which dissolves more salt, thereby causing more ice to melt, and so on. The higher the concentration of dissolved salt, the lower its overall freezing point. There is a limit, however, to the amount of salt that can be dissolved in water.
Does salt make ice last longer?
What liquid freezes fastest?
WaterWater did freeze the fastest with an average of 56.6 minutes. I think that my experiment was fairly accurate. I equally measured out every liquid and made sure my freezer was the same temperature every time.
What liquid stays frozen the longest?
Just pure ice will stay colder longer because water has a much higher specific heat than any other liquid (unless they've discovered some exotic new chemical). For that reason, water absorbs more energy per gram that any other substance to heat.
Does sugar freeze water faster?
We concluded that different substances can make a difference in how fast water freezes. The sugar water froze the fastest.


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The CCE is the Data Centre of the International Cooperative Programme on Modelling and Mapping of Critical Levels and Loads and Air Pollution Effects, Risks and Trends. The CCE website informs you about the work of the CCE, including its mandate, scientific methods and models, data and maps, collaborations as well as its support of environmental policy processes in Europe and elsewhere.
The Coordination Centre for Effects (CCE) was established by the Dutch Ministry of the Environment (VROM) and began its work in 1990. The CCE supports the work of the Convention on Long-range Transboundary Air Pollution (LRTAP) of the United Nations Economic Commission for Europe (UNECE).
The CCE scientifically assesses the risks, expressed as critical thresholds, to forests, lakes and other ecosystems in Europe caused by (long-range) air pollution. This information, which is also summarised in maps of critical thresholds, is useful to understand how national air pollution abatement measures can reduce these risks to ecosystems anywhere in Europe. It also contributed in a novel manner to the scientific support of European air pollution reduction policies. In addition to data on national emissions and costs of emission reductions, now also benefits - in terms of the reduction of risks to ecosystems - could be quantified since the CCE started its work in 1990 in collaboration with a network of National Focal Centres. The use of this information in integrated assessment models enables the policy analysis of cost-effective emission reductions in Europe. Results have primarily been used to support effects-based air pollution reduction policies under the Convention on Long-range Transboundary Air Pollution. The first effect-based LRTAP protocol on "Further Reduction of Sulfur Emissions" (signed in Oslo, 1994) and the later multi-pollutant multi-effects protocol "to Abate Acidification, Eutrophication and Ground-level Ozone" (signed in Gothenburg, 1999) benefited from this scientific support.
Besides information about the work of the CCE, the website contains a list of publications, some of which can be obtained as PDF-downloads from this site or upon request from the CCE.


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(language) A high-level programming language designed by Niklaus Wirth at ETH in 1978. It is a derivative of Pascal with well-defined interfaces between modules, and facilities for parallel computation. Modula-2 was developed as the system language for the Lilith workstation.The central concept is the module which may be used to encapsulate a set of related subprograms and data structures, and restrict their visibility from other portions of the program. Each module has a definition part giving the interface, and an implementation part. The language provides limited single-processor concurrency (monitors, coroutines and explicit transfer of control) and hardware access (absolute addresses and interrupts). It uses name equivalence. DEC FTP archive. ["Programming in Modula-2", N. Wirth, Springer 1985].
Last updated: 1995-10-25


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ITCT 2001 G-4 Flight Track Map
The map shows the 15 flights of the NOAA G4 aircraft during the 2001 ITCT study. The legend indicates the date when the flight originated in yymmdd (2 digit year, 2 digit month, 2 digit day) format and is color coded.
None of these flights were specifically targeted to study the transport or production of ozone. The science objectives of the flights were those of the annual Winter Storms Study; the measurement of ozone was an adjunct effort. Ozone was measured on 11 of the 15 flights.


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By Randy Boswell
A team of Canadian climate scientists is predicting the widespread disappearance of outdoor hockey rinks across the country in the next 50 years due to global warming — with some regions of the sport's spiritual birthplace likely to witness an even earlier eclipse of old-time shinny on natural ice.
"The ability to skate and play hockey outdoors is a critical component of Canadian identity and culture," three researchers from Montreal's McGill and Concordia universities write in the latest issue of the U.K.-based scholarly journal Environmental Research Letters.
"Wayne Gretzky learned to skate on a backyard skating rink; our results imply that such opportunities may not be available to future generations of Canadian children."
The scientists — Nikolay Damyanov and Lawrence Mysak of McGill and Concordia's Damon Matthews — tracked historical temperature trends recorded since 1951 at 142 meteorological stations in every corner of the country.
They also interviewed outdoor icemakers in Quebec and Ontario to find out about what temperatures are required to start up an open-air rink and keep it usable for the duration of the skating season.
The researchers learned that, in general, it takes three consecutive days with a maximum temperature of -5 C to make ice and begin the outdoor skating season.
The length of the season is more difficult to pin down, since a rink's annual life span depends on the local flooding and maintenance regime as well as weather conditions. But the researchers set the same minus-5 C standard to tally the approximate number of days when outdoor rinks should have been available for skaters and hockey players.
"Many individual locations have seen a statistically significant decrease in the number of viable ice-flooding days, suggesting a significant shortening of the length of the outdoor skating season over much of the country between 1951 and 2005," the published paper states, identifying B.C., southern Alberta and the Prairies as the areas with the sharpest drop in the number of game days.
The historical warming effect was noticeable but not as significant in Ontario and Quebec, while research sites in Atlantic Canada showed, overall, no significant change in the durability of outdoor rinks over the past half-century.
Although the researchers did not make detailed calculations projecting the temperature trends into the future, they observed that continued winter warming — as predicted for Canada in standard climate-change models — will result in fewer and fewer viable locations for outdoor rinks in Canada and shorter and shorter seasons in most places where skating persists.
Referring to southern B.C. and Alberta in particular, the researchers stated: "In the most extreme case of the Southwest Canada region, a simple linear extrapolation of the OSS (outdoor skating season) length trend from the last 30 years of our record into the future shows that the number of viable rink-flooding days could reach zero by mid-century."
Matthews told Postmedia News that the research team knows of no other study assessing the state of outdoor rinks in Canada or elsewhere around the world.
But it was "an obvious thing" to examine, he said, because "hockey culture in Canada is almost like nothing else. For a significant fraction of people in the country it's their only exercise and the centre point of winter culture."
The study's conclusions echo concerns expressed anecdotally in recent years by many outdoor icemakers. Meanwhile, a number of municipalities across Canada have been investing in refrigerated outdoor skating facilities that remain open in warmer weather.
Although the researchers did not assess the viability trends for ponds, rivers and other water bodies as skating surfaces, they noted in a summary of their study that the Rideau Canal experienced one of its shortest skating seasons ever this winter.
Organizers of Ottawa-Gatineau's annual Winterlude festival, highlighted by activities along the canal's famous skateway, also made a point this year of expanding the number and range of events held at other venues because of concerns about milder temperatures in recent years.
Matthews said he and his fellow researchers "knew this would be an issue that would resonate with Canadians," and called it a "fortuitous coincidence" that Prime Minister Stephen Harper is a well-known "hockey enthusiast."
Matthews expressed hope that the grim outlook for outdoor hockey rinks might "push the Conservative government to take action" to curb Canada's contribution to global carbon dioxide emissions, widely seen by scientists as a key driver of climate change.
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Ohio did not make it a law to keep birth records until 1867.
Ohio made it a law to record births in 1867. County probate courts kept birth records between 1867 and December 19, 1908. There is no statewide index to birth records from 1867 through December 19, 1908. Births were recorded in a log book. Birth certificates were not created until 1908.
Special Collections and Archives has the birth records for the following counties:
The state of Ohio began issuing certificates for births on December 20, 1908. The Ohio Department of Health holds birth certificates for the state of Ohio from December 20, 1908 to the present. Researchers should contact the Ohio Department of Health.
3640 Colonel Glenn Highway, Dayton, Ohio 45435. Phone: _PHONE_


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The feed expansion machinery manufacturer tells you: 1. The equipment for the broken arch feeding bin and feeder in the pet feed production equipment
A basic reference data in the control system of Jinan feed extruder is the flow of materials. The increase of water, steam and other liquids in the system is based on the flow rate of the materials. Therefore, the stability of the material flow directly affects the production of all extruders. Stability. In order to ensure the stability of the logistics, the system uses differential feeding, that is, placing all the feeding bins and feeders on the load cell, forming a closed loop control between the weighing sensor, the variable frequency feeder and the computer. Feeding.
The basic request for differential feeding is the soft connection between the upper and lower interfaces, that is, the soft connection between the broken arch feeding bin and the pneumatic gate at the upper part of the cartridge body and between the feeder discharge port and the conditioner inlet. Soft convergence, the soft connection between the two places usually uses canvas as the data to connect.
The equipment of the load cell is another important factor affecting the feeding. There are usually two methods for sensor equipment: lifting and loading, both of which can be used depending on the site requirements. When selecting the hoisting, some methods should be selected to ensure the stability of the warehouse. During the production process of the extruder, when feeding into the feeding bin, the falling of the material causes all the bins to sway, and the length of the shaking and shaking is closely related to the length of the sensor lever, although the control program puts the material into the bin. The feed data at the moment uses the data before the feed, but after the material enters the warehouse, if the tank body insists on shaking, it will directly affect the accuracy of the sensor weighing, and request the limit device at the lower part of the warehouse body, and the limit is satisfied. Bit devices do not affect weighing. Another equipment method is the loading, the equipment method does not sway, but all the warehouses are easy to move, which requires the equipment to be fixed on the bracket when the equipment is requested, and the equipment on each side of the lifting bin Limit block to prevent the movement of all the bins.
In the equipment of the broken arch feeding bin of Jinan feed extruder, it is necessary to pay attention to the orientation of the maintenance door, to ensure that the maintenance door can be opened together with the maintenance equipment in the lower part of the maintenance door.
2, Jinan feed extruder double shaft differential conditioner equipment
Because the support frame body of the double-axis differential speed adjuster is a group weldment body, there will be a certain deformation in the process of conveying the feed puffing machine. When the support is deformed, the direct adjustment device will form a conditioner main shaft and a gear box. The output shaft has different axes. When the equipment is running, the noise generated by the roller chain coupling will form the coupling gear and the chain wear. Therefore, it is necessary to adjust the support frame to make the main shaft of the conditioner and the gearbox output shaft the same. axis.
When the conditioning equipment of the Jinan feed extruder is used, the relative orientation of the two spindles is also requested. The equipment can be used according to the symbol of the shaft end, and the relative orientation equipment can also be selected by itself. For details, please refer to the instruction manual.


text:
CONWAY, Ark. (March 6, 2008) – A research letter written by Hendrix assistant biology professor Dr. George R. Harper was published in a recent issue of Nature magazine, a prestigious honor for science scholars. Harper wrote the paper with Dr. David W. Pfennig from the University of North Carolina-Chapel Hill's Department of Biology.
Harper, an evolutionary biologist, studied mimicry whereby non-poisonous snakes take on the colorful characteristics of poisonous snakes in attempt to avoid predators that typically don't harm poisonous snakes. His research focused on non-venomous scarlet king snakes that closely resemble highly venomous eastern coral snakes – both possess brightly colored rings of red, yellow and black encircling the body. Predators avoid such tri-colored ring patterns, possibly without previous experience, but Harper found the non-poisonous mimics were more likely to be attractive to predators because they reside outside an area where the poisonous snakes they mimic reside.
Harper's results provide an evolutionary explanation for why the mimics he studied often occur in areas outside of where the poisonous snakes they mimic are located.
A snake enthusiast – Harper's pet snake Ed, a costal plains milk snake, resides in his Hendrix College office – Harper said his research has already caught the attention of several of his undergraduate students who plan to continue the research.
Nature is the world's foremost weekly scientific journal and is the flagship journal for Nature Publishing Group (NPG). Launched in 1869, NPG publishes journals and online databases across the life, physical and applied sciences and, most recently, clinical medicine. Content encompasses daily news from award-winning journalists, expert opinion and practical methodology, and more high impact research and reviews than any science publisher. More than 30 journals are published in association with prestigious academic societies.
Hendrix, founded in 1876, is a selective, residential, undergraduate liberal arts college emphasizing experiential learning in a demanding yet supportive environment. The college is among 165 colleges featured in the 2008 edition of the Princeton Review America's Best Value Colleges. Hendrix has been affiliated with the United Methodist Church since 1884. For more information, visit _URL_.
For more information, contact Mark Scott at _EMAIL_ or _PHONE_.


Skip to main content
Anders Dahlgren
About Anders Dahlgren
Anders Dahlgren is an art historian and an architect, and a PhD candidate in Art History and Visual Studies since September 2011. Dahlgren's PhD project is about the art, architectural and urban historical project Svensk stad (Swedish Towns), published in two volumes in 1950 and 1953. The project was conducted by the Art History Professor Gregor Paulsson (_PHONE_), but was a collective endeavour that included professionals from various academic disciplines. In the preface 15 people are mentioned as co-authors.
The PhD project investigates the historical and theoretical context of Svensk stad, how the project was carried out (the practice of research), how it has been received (the reception) and how it has influenced following architectural research and practice.


text:
How to Prepare for a Pandemic and other extended disasters.How to Prepare for a Pandemic pandemic /pan·dem·ic/ (pan-dem'ik)
1. a widespread epidemic of a disease.
2. widely epidemic.
Epidemic over a wide geographic area.
n. and Other Extended Disasters
William Stewart William Stewart may refer to:
This book provides valuable information on preparing for a pandemic or other extended disasters with a focus on the needs of a family. It provides information on the planning, implementation, and execution of family preparedness plans with a focus on food, water, safety, transportation, energy, and medical issues that arise during these times. This book is a must-have for those interested in preparing their homes for the possibility of a severe pandemic or other disaster, as well as for public health professionals who are looked upon to provide guidance and support during times of disaster.
104 pages / Paperback / Catalog catalog, descriptive list, on cards or in a book, of the contents of a library. Assurbanipal's library at Nineveh was cataloged on shelves of slate. The first known subject catalog was compiled by Callimachus at the Alexandrian Library in the 3d cent. B.C. #764 Member: $16 / Nonmember: $18


text:
Dr. Eisenstein is a member of the Duke Clinical Research Institute's Outcomes Research and Assessment Group, with a special interest in understanding the relationships between complex interventions in health care systems and the long-term clinical and economic outcomes of patients. He has served as Principal Investigator for phase II, III, and IV economic and quality of life studies conducted alongside randomized clinical trials in cardiovascular, emergency, pulmonary, and vascular medicine and surgery. He also has conducted health technology evaluations making use of innovative research methods designed to better understand key relationships in observation (non-randomized) patient data. This work has included evaluations of the long-term clinical outcomes of coronary artery disease patients receiving drug-eluting vs. bare metal intracoronary stents, and how the use of clopidogrel changes those relationships. He also has conducted several studies assessing factors contributing to the costs of and evaluating different design considerations for multi-center randomized clinical trials.
In addition to his working in traditional health technology evaluation, Dr. Eisenstein has an interest in evaluating information technologies as interventions in health care systems. In this regard, he has collaborated in the design and conduct of large-scale, randomized clinical trials to evaluate clinical decision support systems. The research objective in these studies has been to develop methods for evaluating health information technologies in practice-based settings using a "tool kit" of inexpensive, yet highly scalable methods that make use of data sets created as a byproduct of normal clinical and administrative operations. The use of these evaluation methods has been demonstrated in four clinical trials that include care process, clinical, economic, and quality of life measurements.
Education and Training
- D.B.A., Cleveland State University, 1995


text:
If you are thinking about adding Koi fish to your pond for the first time, here are few tips to ensure they make it to their new home safely.
Upon finding a reputable dealer who has a good selection, take some time to study the livestock and choose wisely:
- The fish should have bright color and its fins should be outstretched. If the fins are folded back, it's not a happy camper and needs treatment.
- The eyes should be clear. Look for any bumps or bruises. Its movement should be smooth and fluid, not jerky.
- Once you've found your new addition, ask the dealer to "bag" it. The store will place the fish in a clear bag with just enough water to cover the fish. Air is more important here, and in some cases they will inject oxygen. Let them know if you have a long ride or if you are by yourself; they can supply you with a box to keep it stable.
- Don't carry the bag on your lap, as that adds heat and raises the temperature of the water. If it's a long, hot ride, the retailer may also supply some ice.
- Upon arriving home, remove the bag from the car and float it on the pond. The temperature of the water in the bag will gradually equalize with the pond in about 15 to 30 minutes.
- Test the water with your hand every so often, and when the temperatures seem relatively the same, release the fish into the pond.
In most cases, the fish will immediately hide somewhere, and will do so for up to several days. Don't be alarmed if you come out a few days later and your new pet is nowhere to be found. One Koi that I added to my pond disappeared for a week; however, it eventually got hungry and decided to join the rest of the gang at feeding time.
Enjoy your Koi!


text:
WIZ-dynamic web-based course presentation system
Item Usage Stats
MetadataShow full item record
The educational potential of the World-Wide-Web is clear. It provides not only a means of communication, but, just as importantly, a means for storing and conveniently accessing a massive amount of information. Such characteristics make it an ideal platform for distance education. One limitation however is the fi.xed nature of the web itself, making guidance and individualized presentation difficult. This thesis presents a project, the WIZ s3'stem, aimed at overcoming this problem. The WIZ system is a dynamic hypermedia system that presents interactive courses over the Internet. It monitors the progress of each student in order to provide a presentation that best matches the individual. Students have the freedom to browse the course material but can return back to the guided presentation by simply clicking on a button. In addition, the WIZ s\'stem exploits the communication (newsgroup and email) facilities of the Internet in order to provide a collaborative discussion environment for courses. WIZ employs sound educational design and software engineering principles to generate affordable, individualized, interactive distance education, independent of time and location.
Intelligent Tutoring Systems
LC5803.C65 O94 1997
Distance education--Computer assisted instruction.
University extension--Data processing.


Question: Is VR Bad For Your Eyesight?
Does VR damage your brain?
There is no scientific evidence that Virtual Reality can provoke constant brain damage to adults and kids.
There are only some symptoms such as dizziness, depression, and collapse that appear while the VR experience.
The technology is still new and requires investigation and research..
Is VR supposed to be blurry?
Question: Is VR meant to be blurry? Answer: Yes, VR is meant to be blurry because you are using two large pieces of lenses in front of your eyes.
Is VR worth getting 2020?
The short answer is that VR is worth it. With some of the best games this generation, innovative controls, and a well-supported ecosystem of VR development, 2021 is a great year to enter the virtual world. Demand is strong and only getting stronger, with 90% of Oculus Quest users being new to VR.
How can I improve my VR quality?
If the VR doesn't start : Go to Oculus App > Settings > General > Allow apps from unknown sources….To increase the quality :Launch SteamVR.Go to Settings.In the Developer tab, modify the Supersampling setting between 0.6 and 2 (0.6 is a low resolution, 2 is very high)Run Twinmotion and launch the VR mode.May 8, 2019
Why is VR Not for under 12?
So, Why is VR not for children under 12 or 13 years old? It's because the side effects of VR on children's vision is still unknown, and manufacturers don't want any future litigation. Moreover, we know that VR causes eye strain, nausea, and headache. Side effects like these are more severe on children than adults.
Is too much VR bad for you?
The most obvious risk involves injuries caused by blundering into real objects while immersed in VR. But there's growing concern about more subtle health effects. Many people report headaches, eye strain, dizziness and nausea after using the headsets.
Is VR bad for your eyes 2019?
Can VR goggles cause other eye conditions? VR goggles are not known to cause worsening of vision or other eye conditions. However, people with conditions like strabismus or amblyopia may develop headaches if they use them for an extended period of time.
How long can you stay in VR?
Spending more than the recommended 30 minutes in VR will — in nearly every case — cause you to lose spatial awareness of the room around you. After 30 minutes, it is much more difficult to identify where things are in the physical world, from inside your headset.
What are the disadvantages of VR?
5 Disadvantages Of Using Virtual Reality In The ClassroomDeteriorates Human Connections. While virtual reality can be a great asset for most of the existent fields of activity, it can also be a huge disadvantage. … Lack Of Flexibility. … Functionality Issues. … Addiction To The Virtual World. … Quite Expensive.Dec 29, 2016
Is VR ok for 11 year olds?
Sony PlayStation VR: The VR headset is not for use by children under the age of 12. HTC Vive: HTC doesn't specify an age, but advises young children not to use the product.
Why is Oculus 13+?
Oculus has had use by under 13 year olds as a terms of service violation since the CV1 came out, so its not a new thing. Now we have the facebook restriction added on as well. IPD is another thing to consider here. Under 13 year olds might not be accommodated by the available IPD options.
What age is safe for VR?
13 years oldAdults should monitor the time their children 13+ spend using the headset and ensure that they take breaks during use. We require everyone to be at least 13 years old before they can create an account to use Oculus devices (in some jurisdictions, this age limit may be higher).
Is VR addicting?
Virtual Reality Addictions The concept of addiction has long been tied solely to substances like nicotine, cocaine, heroin etc., but recent advent of VR technologies has led to an increased psychological dependence amongst individuals on such technologies, thereby creating the same impact as substance addiction.
Can VR kill you?
Probably not. Despite a recent episode of "Black Mirror," which sent a programmer into virtual limbo, killing him, VR's dangers today are a fairly well-known cadre of physical mishaps and nausea. Hitting an object, stumbling or falling remain the most likely way someone can get harmed while encased in VR device.
Why is VR bad?
Nausea, dizziness, disorientation and a number of other motion-sickness related symptoms are common with many VR users and this is exacerbated by the nature of virtual reality: The player's eyes tell their brain they are walking, while their body tells them that they are still.
Why is my vision blurry in VR?
Make sure that you've removed the protective film on the headset lenses. Check that the lenses are clean. Use the cleaning cloth provided in the box to wipe the lenses. … If the headset is too low on your face, your display will appear blurry.
Why is ps4 VR blurry?
Condensation can also be a problem with PSVR; sticking the cold glass next to your warm face can cause some steaming inside the headset, which is going to obscure your vision in virtual reality. If this occurs then, of course, you're going to want to clean the lenses up with a microfiber cloth.
What is the cheapest VR headset?
5 AWESOME (And Cheap!) VR Headsets for Under $100#1 – Google Cardboard – The Best VR Headset on a Budget.#2 – Google Daydream View.#3 – Homido VR Headset for iPhone and Android.#4 – Samsung Gear VR.#5 – Merge VR Goggles.
Does VR cause eye strain?
When using VR, a user's brain is forced to process visual stimuli in a different way than normal. This can cause eye strain, which is simply a case of the eye muscles becoming fatigued. Eye strain will not cause long-term problems, but it is a sign that the eyes and brain need a break from the activity.


text:
Guylaine Couture (Montreal, Quebec)
Awake in the waste
15″ x 8″ x 1″
The soil is a material that seems to us impossible to use until it's disappearance. My book underlines the composition of the ground which degrades by the human being. I wrote some contrasting expressions on the importance of the dirt. These shorts sentences are placed in glass tubes to isolate them, since his study is a scientific subject that we analyze, measure, sterilize, etc.
I use a 1921 scientific book for young public that serves as my soil.The book is damaged, such as the land, which has lost its balance. Concerning waste, the earth transforms well the fiber of the natural materials as paper. But the human has added many material called "inert" as plastic, metal, glass, etc.
We may have an overview of the work, but it is by looking closely that appear the toxic materials here and there, as almost everywhere on the ground. The book is also a clock without hour, but with a pendulum because time is short.
Guylaine Couture lives in Montreal, She has this obsession with creativity and paper for a long time. The re-use of printed documents, pieces of photos, and chosen words is a perpetual game for her. Each book attempts to create a fusion between the contents and the container while questioning the manipulation of the object by the reader. It's like a conversation with her and her concerns.


text:
Cortes / Barrio de Las Letras
Barrio de las Letras is a popular name preferred by many when referring to this area. The name recalls its literary splendor developed throughout the 16th and 17th centuries. Some of the most prominent writers of the Golden Age of Spanish literature settled in this area, such as Miguel de Cervantes, Quevedo, Góngora, and Lope de Vega.
Located between the Paseo del Prado and the Plaza de Santa Ana, Barrio de las Letras is one of the most charming and interesting places in Madrid, with a bohemian flavor and magic quality that makes it unique in the world. It still retains an aura of tradition in its architecture, its narrow cobblestone streets, its many pedestrian streets, its history and its tranquility.
Most of the buildings that remain in the Barrio de las Letras were built at the end of the 19th century and the beginning of the 20th century. However, the Palace of the Count of Tepa and the Royal Academy of History correspond to the 18th century. Other buildings of architectural interest are the Spanish Theater, the Simeón Building and the Ateneo de Madrid.
museums and cultural venues
Church and Convent of Las Trinitarias Descalzas


What is iridology?How iridology work?
What is iridology?
How iridology work?
Explain the science of it. How is the eye literally the window to the soul?-Iridology is the science of the iris, or colored portion, of the eye. The iris contains bundles of thousands of nerve fibers and is a reflection of the entire body.The iris is connected to every organ and tissue of the body by way of the brain and central nervous system through the optic nerve. The optic nerve connects to the central nervous system (CNS) which is the main communication link to everything that goes on in the body.Think of your brain as your body's 'hard drive;' it remembers everything that ever happened to your body. Your iris is then like the 'file folder.' So 'reading' the iris to find out what is going on in the body is similar to how one reads a computer screen to access what's in a computer.
Iridology is the study of the iris as associated with disease. The 'iris' of the eye, is the most complex tissue structure in the human anatomy, which is the exposed nerve endings that makes up the colored part of the eye. From the time we are conceived the iris and all its fibers are formed along with the brain before any other organ is developed, making the eyes an extension of the brain endowed with thousands of nerve endings, microscopic blood vessels, muscle and other tissues. The iris is connected to the tissue of the body by way of the brain and nervous system. The branched nerve fibers (such as dendrites) receive their impulses by their connections to the optic nerve and spinal cord. Nerve fibers in the iris respond to changes in body tissues by manifesting a reflex physiology that corresponds to specific tissue changes and locations, by way of line patterns, fiber structure and color changes in the iris. By this means the body's inherited and/or acquired state of health sends neural reflexes to the fibers within the iris causing groups of fibers to change by way of line patterns, characteristics, shapes, structures, forms and color in the iris and that is what an Iridologist studies.
How to Read the Iridology color?
Iiridology Charts
bernard jensen Charts
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Iridology PDF eBooks
what-the-eye-reveals iridologia-una-alternativa-diagnostica iridiology-chakra iridiologia-simplificada como-afecta-el-color-del-iris-en-la-salud Iridology A systematic review Iridología iridologia Iridologia Teoria Y Práctica (Spanish Edition) By Jesús Iridología NATUROPATÍA – CLASE 21 Iridologia eAyurveda Iridologia Correlação entre ansiedade e anéis de tensão
iridology camera applications(Where need it?):
1,Health products distributor
2 distributor of health products, health products stores and counters
3, health product manufacturers and research institutes,
5, sub-health counseling
.6 care clinics,
7 nutrition guidance counselors, other industries
Production, sale, offer OEM & ODM.
Order Hotline: 0755-888-56563 (Mark)
Email: _EMAIL_
Our advantage(Why choose us?):
1.Original software.
2.OEM Accepted.
3.In stock.
4.Professional after sales service.
5.Different language version.
6.Free upgrade software forever.
7.Wholesale price.
8.CE Cetificate.
Sale Cousultant : Mrs Lucy
Sale Consultant : Mr Mark
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So C99 blessed the commonly-used "flexible array member" hack to allow us to make structs that could be overallocated to suit our size requirements. I suspect it's perfectly safe on most sane implementations to do this, but is it legal in C to "underallocate" if we know in certain situations that we won't need some members of a struct?
Abstract Example
Say I have a type:
struct a {
 bool data_is_x;
 void * data;
 size_t pos;
If data_is_x, then the type of data is a type that needs to use the pos member. Otherwise, the functions that work with this struct won't need the pos member for this particular copy of the struct. Essentially, the struct carries around information about whether or not it has a pos member, and this information will not be changed within the struct's lifetime (outside of evil mischief, which will break pretty much anything anyway). Is it safe to say:
struct a *a = malloc(data_is_x? sizeof(struct a) : offsetof(struct a, pos));
which will allocate space for a pos member only if one is needed? Or does it violate a constraint to use cast space that is too small to a struct pointer, even when you never use the members in question?
Concrete Example
My real-world use case is a bit involved; it's here mainly so you can understand why I want to do this:
typedef struct {
 size_t size;
 void * data;
 size_t pos;
} mylist;
The code for mylist_create specifies that, for size > 0, data is an array of contiguous data that is size items long (whatever an item may be), but that for size == 0 it is the current node of a doubly-linked list containing the items. All the functions that work with mylists will check whether size == 0. If it does, they'll handle the data as a linked list with the "current" index being whichever node data points to. If not, they'll handle the data as an array with the "current" index stored in pos.
Now if size == 0 we don't really need the pos member, but if size > 0 we will. So my question is, is it legal to do this:
mylist *list = malloc(size? sizeof(mylist) : offsetof(mylist, pos));
If we guarantee (on penalty of undefined behavior) that, while size == 0, we will never try to (or need to) access the pos member? Or does it say somewhere in the standard that it's UB to even think about doing this?
share|improve this question
This is a very good question, and I'm sad to say I don't know the answer. I wish you'd given a simpler example case though; I have a feeling folks will have a hard time following... +1 anyway. – R.. Sep 9 '11 at 2:07
_USER_.. - It's essentially my use case; I used it because I thought a more abstract example might not make sense and raise the question "Why are you doing this?" (which I myself often ask when I see people trying to do things that may be inadvisable). If you think it'll make the question clearer, I can change it to be simpler, or I could leave it and add a simpler version. – Chris Lutz Sep 9 '11 at 2:09
I would leave it, but a simpler version might be nice too. – R.. Sep 9 '11 at 2:13
5 Answers 5
up vote 4 down vote accepted
malloc itself doesn't care at all how much memory you allocate for a structure, it's the dereferencing of memory outside the block that is undefined. From C99 Address and indirection operators:
And, from 7.20.3 Memory management functions, we find (my italics):
Hence, you can do something like:
typedef struct { char ch[100]; } ch100;
ch100 *c = malloc (1);
and, provided you only ever try to do anything with c->ch[0], it's perfectly acceptable.
For your specific concrete example, I'm not too sure I'd be that worried, assuming that what you're concerned about is storage space. If you're concerned for other reasons, feel free to ignore this bit, especially since the assumptions included within are not mandated by the standard.
From my understanding, you have a structure:
typedef struct {
 size_t size;
 void * data;
 size_t pos;
} mylist;
where you want to use only data where size is 0, and both data and pos where size is greater than 0. This precludes the use of putting data and pos in a union.
A significant number of malloc implementations will round up your requested space to a multiple of 16 bytes (or some greater power of two) in order to ease memory fragmentation issues. This isn't required by the standard of course, but it is pretty common.
Assuming (for example) 32-bit pointers and size_t, your twelve bytes of structure will most likely take up a 16-byte arena header and a 16-byte chunk for the data. This chunk would still be 16 bytes even if you only asked for 8 (ie. without pos).
If you had 64-bit pointer and size_t types, it might make a difference - 24 bytes with pos and 16 without.
But even then, unless you're allocating a lot of these structures, it may not be a problem.
share|improve this answer
Are you sure this is defined? I would like it to be, but I can't find a justification. – R.. Sep 9 '11 at 2:14
This is what I suspected, but I figured it was thin enough ice that I might as well ask and see if the many fine C gurus here might dig up an interpretation of the standard that prohibits doing this. (Though in your example, wouldn't you'd need to use (*c)[0]?) – Chris Lutz Sep 9 '11 at 2:15
Also I think it's possible that the answer could differ for paxdiablo's example (with an array) and your example (with a struct). Certainly from a "moral" standpoint, doing this hack with a struct seems more offensive. – R.. Sep 9 '11 at 2:19
I think your standards citation takes the cake. I'll accept this tomorrow if no one's come up with anything opposing this. – Chris Lutz Sep 9 '11 at 2:33
I think the big question is which object you are "accessing". If anything in the standard implies that you are "accessing" the structure/array, then the behavior is undefined. If on the other hand you only "access" elements/members in the space allocated then it seems okay. It might be worth reading the rather roundabout text on flexible array members in the standard to better understand this... – R.. Sep 9 '11 at 2:48
It is perfectly legal, but you should probably make it less obscure by having two structs, and when you read it:
struct leaf_node {
 size_t size;
 void *data;
 size_t pos;
struct linked_node {
 size_t size;
 void *next;
void *in =...;
if (*(size_t*)(in) == 0) {
 struct leaf_node *node = in;
} else {
 struct linked_node *node = in;
This goes more hand-in-hand with the standard that paxdiablo quoted, that you can cast the pointer to any data pointer. If you do it this way you will also always make sure you cast it to a struct that fits in the allocated buffer (an unnecessary but convenient feat).
What paxdiablo said about a minimum size of 16 bytes on 32-bit systems is often true, but you can still allocate big chunks to get around that.
On a 32-bit system the linked_node will use 8 bytes. You must use pools to benefit from what you are trying to do.
struct leaf_node *leaf_pool = malloc(N*sizeof(struct leaf_node));
struct linked_node *linked_pool = malloc(N*sizeof(struct linked_node));
Of course you should never realloc the pools, but allocate new pools as needed and reuse nodes. In this case a single leaf_node will use 12 bytes.
Same applies to linked_node, which will use 8 bytes instead of 16 bytes if you allocate them in a pool.
There will be no performance bottleneck as long as your structs aren't using __attribute__ ((packed)) in GCC, in which case your structs could get very badly aligned. Especially if you have, for example, an extra char in your struct giving it a size of 13 bytes.
Now if we go back to your initial question, the pointer you use to point to allocated data doesn't matter as long as you make sure you don't access data outside of the buffer. Your struct is essentially like a char string, and you check if the first size_t is a "null byte", if it is then assume the buffer is smaller. If it is not null, then the "string" is assumed to be longer and you read more data. The exact same risks are involved, and the only difference after compilation is the size per element read. There is nothing magic about using [el] for strings compared to casting to a struct pointer and reading elements, as you can verify by just as easily causing a segfault using [el].
share|improve this answer


What are some important combinatorial and algebraic interpretations of the coefficients in the polynomial
$$[n]!_q = (1+q)(1+q+q^2) \ldots (1+q+\cdots + q^{n-1})?$$
As motivation, I will give three interpretations, ask for a fourth, and raise a related question about the unimodality. I would be particularly interested in answers using the RSK-correspondence or subspaces of $\mathbb{F}_q^n$.
 1. Given a permutation $\sigma \in \mathrm{Sym}_n$, let $\mathrm{inv}(\sigma)$ denote the number of inversions of $\sigma$; that is, pairs $(x,y)$ with $x < y$ and $\sigma(x) > \sigma(y)$. Then $[n]!_q = \sum_{\sigma \in \mathrm{Sym}_n} q^{\mathrm{inv}(\sigma)}$.
 2. An element $x \in \{1,\ldots, n-1\}$ is a descent of $\sigma \in \mathrm{Sym}_n$ if $\sigma(x) > \sigma(x+1)$. The major index $\mathrm{maj}(\sigma)$ is the sum of the descents of $\sigma$. Then $[n]!_q = \sum_{\sigma \in \mathrm{Sym}_n} q^{\mathrm{maj}(\sigma)}$. I think this is due to MacMahon.
 3. In the 'inside-out' version of the Fisher–Yates shuffle on an $n$-card deck, at step $j-1$, card $j-1$ from the top is swapped with one of cards in positions $0, 1, \ldots, j-1$ from the top, chosen uniformly at random. These choices are enumerated by $1 + q + \cdots + q^{j-1}$. After $n$ steps (starting with $j=1$), each permutation has equal probability. (This is essentially coset enumeration in the symmetric group by the chain $\mathrm{Sym}_1 \le \mathrm{Sym}_2 \le \ldots \le \mathrm{Sym}_n$.) Hence $[n]!_q$ enumerates permutations according to the sum of the positions chosen at each stage.
Does the normal Fisher–Yates shuffle have a similar combinatorial interpretation? Is there a more natural interpretation of the $q$-power, still using the inside-out Fisher–Yates shuffle?
Finally, (1) makes it easy to see that $[n]!_q$ is symmetric, i.e. the coefficients of $q^m$ and $q^{\binom{n}{2}-m}$ are the same: use the Coxeter involution, thinking of $[n]_q!$ as the Poincaré series of the Coxeter group $\mathrm{Sym}_n$. This can also be seen in a similar way from (2). But it does not seem to be obvious from (3).
Which interpretation is the best way to show that the coefficients in $[n]!_q$ are unimodal, i.e. first increasing then decreasing?
 - $\begingroup$ Statistics on the symmetric group with the same distribution as inversion number (and major index, etc.) are called "Mahonian," which might be a helpful keyword for you. $\endgroup$ – Sam Hopkins Dec 28 '19 at 18:47
 - $\begingroup$ Shouldn't the statement that "$[n]_q!$ is symmetric" (I guess you mean $[n]!_q$ there, for consistency with the rest of the question) be that the coefficient of $q^m$ is the same as that of $q^{\binom n 2 - m}$, not of $q^{n - m}$? $\endgroup$ – LSpice Dec 28 '19 at 20:26
 - $\begingroup$ _USER_: yes, thank you for the correction. $\endgroup$ – Mark Wildon Dec 29 '19 at 12:32
This answer concerns a geometric/Lie-theoretic interpretation of $[n]!_q$.
$[n]!_q$ gives the number of points in the full flag variety of full flags of subspaces in an $n$-dimensional vector space $\mathbb{F}_q^n$ over the finite field $\mathbb{F}_q$.
Recall that the full flag variety (over any field) has a natural stratification, the Bruhat stratification. Due to the above point-counting remark, it follows that the coefficient of $q^i$ in $[n]!_q$ is the number of $i$-dimensional cells in the Bruhat stratification.
There is also a way to deduce the unimodality of the coefficients from this geometric perspective. Namely, the partial order on the Bruhat cells whereby $C \leq C'$ if $C$ is contained in the closure of $C'$ is called the Bruhat order or strong order. The strong order can be viewed as an order on the symmetric group because the Bruhat cells are naturally labeled by permutations. Strong order is graded, and the rank sizes are precisely the coefficients of $[n]!_q$ (i.e., the number of permutations with given inversion number). Richard Stanley showed in the "Weyl groups..." paper cited below that in this situation (when you have a complex projective variety with a cellular decomposition satisfying certain conditions), the poset in question is necessarily graded, rank-symmetric, rank-unimodal, and strongly Sperner, which in particular implies the unimodality of the coefficients of $[n]!_q$. His proof employed the hard Lefschetz theorem and so can hardly be called elementary, but it is conceptual.
Stanley, Richard P., Weyl groups, the hard Lefschetz theorem, and the Sperner property, SIAM J. Algebraic Discrete Methods 1, 168-184 (1980). ZBL0502.05004.
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 $\begingroup$ I have trouble parsing this sentence. Does it mean the same thing as "It gives the number of full flags of subspaces …"? If so, then this seems to be explaining the significance of the number $[n]!_q$ itself, not of the coefficients when it is viewed as a polynomial in $q$. $\endgroup$ – LSpice Dec 28 '19 at 18:23
 - $\begingroup$ Yes, this is an interpretation of the number $[n]!_q$, not the coefficients of the polynomial per se. To get an interpretation of the coefficients you can use the Bruhat stratification. I will edit to include this. $\endgroup$ – Sam Hopkins Dec 28 '19 at 18:29
 - $\begingroup$ Since a Bruhat cell of dimension $i$ corresponds to a symmetric-group element of length $i$, and since the length of a symmetric-group element is its number of inversions, then this is the same as interpretation (1) in the post, right? $\endgroup$ – LSpice Dec 28 '19 at 18:33
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 $\begingroup$ _USER_: that's right but this is a more geometric way of looking at it, and still fundamental imo. $\endgroup$ – Sam Hopkins Dec 28 '19 at 18:41
 - $\begingroup$ I also added something about unimodality from the Bruhat stratification perspective. $\endgroup$ – Sam Hopkins Dec 28 '19 at 19:36
In FindStat, the database of combinatorial statistics, the major index of a permutation is _URL_ By clicking "search for distribution" there, you will find other statistics that (FindStat thinks) are equidistributed with major index. I get 41 results. As mentioned in a comment above, these statistics are called "Mahonian" in honor of MacMahon.
This answer concerns an interpretation of $[n]!_q$ coming from invariant theory.
There is a natural action of $S_n$ on $V=\mathbb{C}^n$, and hence on polynomial functions on $V$. This action preserves degree. The coinvariant algebra is the quotient of the polynomial functions on $V$ by (the ideal generated by) the $S_n$-invariant functions of positive degree. This (finite-dimensional!) algebra inherits an $S_n$ representation. As an ungraded $S_n$ module it is isomorphic to the regular representation (this was first proved by Chevalley). But it also inherits a grading, giving a natural grading to the regular representation of the symmetric group. Various fundamental results in invariant theory (the Chevalley-Shephard-Todd theorem, Molien's theorem, etc.) imply that the Hilbert series of the coinvariant algebra is $[n]!_q$. Hence the coefficient of $q^i$ in $[n]!_q$ is the dimension of the coinvariant algebra in degree $i$.
There is a connection here to RSK, and since the question asked about RSK


text: The Mother of God and the Christ Child are in the company of John the Baptist and his mother, Elizabeth. This devotional painting radiates quietude of a virtually sublime character. The pictorial type known as 'sacra conversazione' (sacred conversation) was extremely popular. Successful artists like Bellini produced several versions of it, combining figures based on standardised models. This explains why Elizabeth and John cannot see the Infant Jesus, but only Mary's back. The painting undoubtedly owes its aura in good part to the brilliant blue produced from the precious lapis lazuli.


Ask The Experts: Diabetes and Affects on Muscle - MedicineNet
Diabetes Q&A by Dr. Mathur
How does diabetes mellitus affect the muscle?
Diabetes mellitus can affect the muscle in several ways.
Diabetes mellitus promotes atherosclerosis which impairs the circulation to many tissues of the body. When the muscles of the limbs are affected, the decreased blood flow can lead to cramping and to painful walking (peripheral vascular disease resulting in claudication). In the worse case scenario - this can lead to death (infarction) of the localized areas of muscle. This is characterized by local pain in the involved area. Blood testing can demonstrate elevated muscle enzymes (CPK, aldolase). When the heart muscle is affected by such atherosclerosis, it can lead to heart attack.
Diabetes mellitus can also damage the nerves that supply the hands and feet. This can lead to inadequate nerve supply and further muscle wasting. Persons with longstanding diabetes mellitus can develop pain, and muscle twitching, in addition to muscle wasting of the muscles around the shoulders and hips (limb girdle wasting). This condition is referred to as diabetic amyotrophy.
In the majority of people with diabetes, muscle strength is preserved well enough to allow for modest physical activity under a doctor's supervision, This is not an excuse for someone with diabetes to refrain from physical activity!
Thank you for your question.
Last Editorial Review: 8/30/2012


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The impact of the removal of the Multi-Fiber Arrangement on textile and cotton trade of the United States and China
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Textiles and apparel trade has been governed by the Multi-Fiber Arrangement (MFA) for three decades. Trade restrictions have generated substantial welfare losses and price wedges in exporting and importing countries through trade distortions. Beginning in 1995, textiles and apparel trade underwent fundamental changes in trade flows and patterns. The World Trade OrganizationÂs Agreement on Textiles and Clothing (ATC) aimed to remove all MFA quotas by January 2005. This study established an equilibrium displacement model to investigate the impact on textile and cotton sectors of different countries and country-groups of removing the MFA quota. The model specifies the basic linkages of textile and cotton markets in the United States, China and four other country-groups. With different assumptions about U.S. textile supply elasticity, foreign cotton exportersÂ reaction and changes in the U.S. farm program payments, alternative scenarios are simulated to predict changes in domestic and import demand for textiles and apparel, import demand for U.S. cotton, domestic and import price of textiles and apparel, U.S. cotton price and adjusted world cotton price. Uniform distribution was imposed for selected parameters involved in the model to overcome the deficiency of equilibrium displacement models of assuming certainty of known related parameters. Results indicate increased import demand for U.S. cotton by China, higher U.S. cotton supply, more textile and apparel supply from China, decreased domestic demand for U.S. cotton, and lower U.S. domestic demand for textiles and apparel. However, prices of both textile and cotton markets experience both positive and negative changes under different scenarios. Holding other assumptions unchanged, when farm program payments increase, U.S. cotton price and adjusted world cotton price declined. When farm program payments are held constant, prices rise. The changes expected in U.S. cotton price are, in absolute value, greater than those of the adjusted world price.
Xia, Yan (2004). The impact of the removal of the Multi-Fiber Arrangement on textile and cotton trade of the United States and China. Master's thesis, Texas A&M University. Texas A&M University. Available electronically from


text:
Sight Reading Factory is a fantastic resource to use at home, especially during a potential period of online learning. My school closed on Tuesday and now we are entering day 3 of uncharted territory!
When distance learning becomes necessary, Sight Reading Factory can be super effective. What could be even better than using Sight Reading Factory? USING SIGHT READING FACTORY BEING FREE!
Here is the message send from the co-founders of Sight Reading Factory:
If you're looking for a remote eLearning solution for your music classes while schools in your district are closed due to the COVID-19 virus, Sight Reading Factory is offering free student accounts during the time your school is closed.
If you're not familiar with SightReadingFactory.com, we are a cloud-based application for practicing sight reading. With the assignments feature, students can record themselves performing a teacher-configured sight reading exercise directly through our online platform. Students can then submit their recording to the teacher for grading. SRF works on virtually any modern device – smartphones, tablets, laptops, Chromebooks, etc. With SRF student accounts, teachers can organize students into classes/groups and can also view reports on their students to monitor their usage and track progress.
Our unique composition engine allows you to customize and configure sight reading exactly to the needs of your students and generate a virtually unlimited supply of unique sight reading exercises. Click here to try out a free demo and generate some sight reading exercises.
Check out this page for more information on SRF student accounts and the assignments feature.
If your school will be closed due to the COVID-19 virus and you'd like to take advantage of this offer of free student accounts during the time your school is closed, please write to us at _EMAIL_.
How to Use Sight Reading Factory for distance learning!
Before doing anything I list below, just go to their website and try the demo on their home page; you do not need to give an email or fill anything out. Once you see how easy and effective the program is, you will be sold on the plan below!
This plan will work for you and your students:
- Contact Sight Reading Factory at: _EMAIL_. They will provide you with one code to disseminate to your choir
- Log onto Sight Reading Factory as a teacher and create a class. Just click on CLASS and then create a NEW class. You can create as many classes as you want. I suggest keeping this simple. Perhaps you could have a beginner and advanced class, and have your students self-select into the appropriate class; you could create a class for each chorus that you have.
- Create an assignment(s) – and select a due date. Next, they ask for a key signature, time signature, length (number of measures), tempo, and a few other/less important things. The bottom line is that the options are restrictive enough that you won't get confused. Create as many assignments as you'd like. Each assignment will meet your specific parameters but each student will receive different assignments. It takes well under one minute to create an assignment. The best part about this is that you can just "duplicate" the same assignment over and over again; since every example is brand new, students will receive a different assignment every time, even if your parameters remain exactly the same!
- Send the code out to your students and they can instantly join the class(es) you've set up. They will see the assignments when they join your class!
The purpose of your assignments
Assignments can be as simple or challenging as you wish. I suggest keeping them simple as the goal is to keep our singers positive and engaged through this difficult time.
How assignments work:
Students will click on an assignment and have endless tries before submitting their take to us. (Students can sing directly into any computer mic.) They can even hear the correct notes played alongside their recorded performance. This means, they will have a clear sense of how they did before submitting. While students cannot redo any exercise, they can try over and over again; when they try again, a new exercise will be generate that meets the exact same parameters.
When they submit an assignment, we will know how many times they tried to complete the assignment (how many different assignments they attempted).
How to Grade in this Current Climate:
Our goal is to motivate our students and keep them involved. I would suggest grading on a simple scale. 4 = outstanding, 3 = excellent, 2 = fair (passing), 1 = needs improvement.
Since our students are at different levels, we want to encourage all students to be successful. A score of a "1" is for a student who doesn't submit an assignment or makes little effort. I would recommend a passing score of "2" for any student who makes an effort. A score of "4" is for students who excelled on the exercise and a "3" is for hardworking students who make a serious effort with a decent result or talented sight-singers who don't make the effort to refine their effort.
If put into a 10 point scoring system, it could look like this:
- 10 = outstanding
- 9 = excellent
- 8 = fair
- 5 = needs improvement
One more GREAT Sight-Reading Factory Idea!
This is not only another effective idea, but it is an alternative for students who do not have the same access to a modern computer/chromebook/mic. All they need is access to email and a printer.
On Sight Reading Factory, create an 8-measure exercise that meets your parameters (for example, 4/4 time, key of D major, notes/rests no faster than 1/8 note, range of an octave), and make a PDF of each exercise.
From there, send the PDF assignments out to your students and ask them to label the pitches below the notes (d, r, m, f, etc) and the rhythms above the note (1+2+3+4+). If you have google classroom or another method of submission, have them submit it to you. You can always send a sample 8-measure exercise with an answer key for all students in order to ensure they understand the concept.
We are living in a scary and confusing time right now. Health comes first. We must take care of ourselves, our families, and our community.


text:
Evolution can fall well short of perfection. Claire Ainsworth and Michael Le Page assess where life has gone spectacularly wrong
THE ascent of Mount Everest's 8848 metres without bottled oxygen in 1978 suggests that human lungs are pretty impressive organs. But that achievement pales in comparison with the feat of the griffon vulture that set the record for the highest recorded bird flight in 1975 when it was sucked into the engine of a plane flying at 11,264 metres.
Birds can fly so high partly because of the way their lungs work. Air flows through bird lungs in one direction only, pumped through by interlinked air sacs on either side. This gives them numerous advantages over lungs like our own. In mammals' two-way lungs, not as much fresh air reaches the deepest parts of the lungs, and incoming air is diluted by the oxygen-poor air that remains after...
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Take the 2-minute tour ×
What is the shortest word in the Torah?
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closed as not a real question by Isaac Moses Jun 16 '11 at 22:09
2 Answers 2
up vote 1 down vote accepted
הַאֲזִינוּ פרק לב פסוק ו
הַ לְיְהוָה, תִּגְמְלוּ-זֹאת
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I don't understand how this answer could be accepted without any source justifying that this is actually a word. – Curiouser May 23 '11 at 16:36
_USER_ - Note the usernames. – WAF May 24 '11 at 23:10
There are a number of words of two letters, which could all count as the shortest.
But according to the Ibn Ezra, the heh which begins Devarim 32:6 is connected to the lamed and is not a word on its own. This is a famous mechlokets. See a nice video on the topic here.
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text:
Ay, Hasan Salih
xmlui.mirage2.itemSummaryView.MetaDataShow full item record
This text searches for a possibility of thinking with images along with a nomad thought on images by following some symptoms and traits that appear on works in the exhibition "grows between among other things". Each chapter written during the process of creation of these works are devoted to the concepts that define these symptoms and traits. To start with, the extent of multiple connections within each piece and between every other work is discussed in terms of space. In this context, the spatial differences which results from unstitching and weaving of the strings are explained by the production of felt, a nomadic invention. Then, the necessity of a vigorous eye that can construct these multiple relations and form the interconnections, and the reasons of this being possible by nomad images, is discussed by examples. In the next chapter, an affective vision and sensation enabled by a particular positioning immanent in nomad image is discussed with respect to motive-ground relations. After that, the use of lines forming affections rather than passive feelings are compared via Egyptian relief, Greek and Gothic decorations. The fact that repetition without a certain purpose is inclusive of some sort of empiricism and that the repetition as such presents itself in the form of multiplicity are examined in the next chapter. Following that, the formation of nomadic floating space are elaborated in Triptychs in terms of movements, and speed. In the chapter Desiccation/Contraction/Expansion, the relation of nomad image with materiality is explored from the perspective of the pairs, matter-form and content-form. Finally, affirmative meaning of subtraction displayed as a gesture throughout the exhibition is explained in relation to works. It is obvious that this text might yield some gaps in the reader's mind when solely approached. Therefore, treating the text and exhibition together will be more suitable for the text and also more comfortable for the reader.
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In today's constantly evolving world, there is a demand for new skill-sets every year. In fact, according to a report by Udemy, 78% of L&D managers said their biggest challenge was keeping their employees' skills up to speed with change.
At the same time, the L&D landscape itself is also evolving at a faster pace than ever before. In line with that, polling 263 L&D managers, Udemy's report also shed light on the direction the L&D landscape is moving towards in 2018 and beyond. Here are the findings summarised as three key predictions.
#1 Personalised learning experiences through artificial intelligence (AI) and machine learning
While only 4% of L&D offerings are powered by AI and machine learning today, 24% of L&D managers revealed that they plan to leverage on machine learning over the next few years.
By studying learner behavior over large data sets, AI and machine learning can provide course recommendations and help L&D professionals understand and predict what employees want to learn.
This will enable L&D managers to provide a more personalised learning path for their employees; which 50% of L&D managers have revealed they are intending to do in the next few years - up from the 46% who were already doing so now.
#2 Gamification as a game-changer
Currently, only 8% of L&D programmes leverage on gamification. Moving forward, 31% of respondents have indicated that they intend to add gamification to their corporate learning programs to make learning engaging while helping staff retain and apply their new knowledge.
However, the report noted that in order for gamification to be effectively leveraged as a learning tool, L&D leaders must understand the science behind it and design their programs thoughtfully.
Shelley Osborne, head of L&D at Udemy, said: "At the end of the day, gamification is really about trying to create a learning experience to help motivate people to change their behavior."
#3 Virtual reality and augmented reality is gaining ground
Although virtual reality (VR) and augmented reality (AR) is still a small component of today's L&D resources (only 4%), a fifth of L&D managers (20%) revealed they are planning to introduce it in the next few years.
AR will enable "in-the moment learning" programmes by enhancing natural environments by overlay digital objects for guidance or provide a remote instructor to provide step-by-step direction and correction on the job.
At the same time, VR will help L&D leaders develop immersive apprenticeship-style learning at scale, creating an environment for employees to apply what they learn in "real-world" situations. The report noted that as costs for VR come down, organisations are also starting to use it for soft skills such as diversity & inclusion VR training which lets employees experience the workplace in someone else's shoes.
Additionally, Udemy's report revealed that more L&D managers are planning to encourage social learning in the next few years - 13% compared to the 9% who are doing so today; while less are planning to embed learning into the workflow - 35% compared to 46%.
Photo / 123RF


text:
Although moth orchids (Phalaenopsis) must account for 80% of all orchid sales these days, there are other orchids available and Cambria orchids make up most of these in summer. Moth orchids are popular because they are warm-growing orchids that tolerate rather dark and centrally heated rooms (note the use of 'tolerate') but Cambria orchids prefer cooler conditions – down to 10c at night in winter and up to 20c or so during the day in summer. This preference for cool winter conditions makes them suitable for conservatories as long as they are heated in winter and not in full sun so the plants bake in summer. They like good light and, unlike the moth orchids, they form 'psuedobulbs' at ground level, about one per year on each growth axis and from these, linear leaves and one flower spike will grow.
Like cymbidiums, they prefer a high nitrogen feed from spring to mid summer and then a high potash feed till autumn. They are pretty tough but if they dry out or the atmosphere is too dry the leaves get 'stuck' as they grow and develop a concertina pattern. This is unsightly and a reminder of your lack of care (for a year or so till they drop off) but will not harm the plants. This happens to pansy orchids (miltoniopsis) too.
Despite the small name, these are complicated plants in as far as the name covers a huge range of plants that have little in common visually. The hybrid began its life in 1911 with Charles Vuylesteke. He crossed Odontoglossum crispum with a Miltonia and Cochlioda noetzliana. You can see that there are several genera involved already! The hybrid was names Vuylestekeara.
A decade later this was crossed with another Odontoglossum and the hybrid was named Vuylestekeara Cambria 'Plush'. Nowadays it is impossible to say what a Cambria orchid looks like because they are so varied. But most have small or medium sized flowers in yellow, purple, orange, red and white with six to ten flowers per stem – but there are exceptions and some have a little scent.
They generally flower in summer but flowering can be at almost any time. These two are not necessarily representative but are two I have at home flowering now.


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I cannot seem to find where the SHUTDOWN ALL command reference is in the CA OPS/MVS Event Management User Guide. This command is entered prior to our IPL. What does it do? If it's a REXX exec where is it?
This is a rule created by the customer and they needed to know where to look for it.
Go to the OPSVIEW panel.
Customer found the command rule.
- Select 4 Control - Control CA OPS/MVS
- Select 5 AOF Control - Control Automated Operations Facility
- Select 1 AOF Control - Control AOF Rules
- On the following panel, if the rule dataset is there, press Enter
- Select each RULESET member, using the line command S,
- Using the line command B, look for the member named SHUTDOWN.
- Using the line command B, have a look inside the SHUTDOWN member to see what that shutdown member is doing.


text:
NW Cotton Towns Learning Journey
Your guide: John Mortimer, author of "Industrial Lancashire" (1897)
Step 1: Liverpool to Manchester; Manchester to Stockport; Stockport to Ashton
Step 2: Ashton to Manchester; Manchester to Oldham; Oldham to Rochdale
Step 3: Rochdale to Bury; Bury to Accrington; Accrington to Blackburn
Step 4: Blackburn to Burnley; Burnley to Clitheroe; Clitheroe to Preston
Step 5: Preston to Wigan via Chorley; Wigan to Bolton
Step 6: Bolton to Salford; Salford to Manchester
Click on the steps below to explore.
North West Cotton Towns Learning Journey Step 6
BOLTON TO SALFORD
We follow the path of the Manchester, Bolton and Bury canal back to Salford, a populous town of over 200,000 inhabitants; we could just as easily take a tram car down the ten-mile broad highway that separates Bolton from the Salford Borough proper. Salford is an ancient town, if now in the shadow of Manchester, and it has its own proud history and textile heritage. Salford had a cloth hall in Greengate, and was an important centre for the production of woollen goods as well as fustians before Manchester's cotton industry dominated. Textile manufacturers constructed their mills on the banks of the Irwell and its tributaries, and the coming of both the Bridgewater and Manchester, Bolton & Bury canals (and the coal carried) only increased their number. By 1818 Manchester, Salford and Eccles jointly had 80 cotton mills. Once Manchester and Oldham began to dominate the spinning industry, Salford became a centre for finishing trades and power loom weaving, as well as machine and tool making. The Manchester Ship Canal has had a huge effect, with the Dock complex including offices, the Customs House, various warehouses, stores and grain silos.
SALFORD TO MANCHESTER
From Salford we may travel by the canal, tram, or even walk back to Manchester, crossing the River Irwell, which divides the two cities, back to where we began our grand tour of the Lancashire Cotton District. Here the cycle of trade begins again, and we might once again travel to Liverpool, perhaps this time on the Liverpool-Manchester railway, to again survey this great manufacturing district, the pride of the Empire and truly, the Workshop of the World.
Here, I bid you farewell. I hope you have enjoyed our tour together. Why not read more from the links on each step, or perhaps travel out yourself sometime along the path we have traced together? Who knows, perhaps we will meet along the way...