http://www.eurekalert.org/pub_releases/2...110414.php
ARTICLE: In nature, the right amount of death at the right time might actually help boost a species' population density, according to new research that could help in understanding animal populations, pest control and managing fish and wildlife stocks.
In a paper in the journal Trends in Ecology and Evolution, a Princeton University researcher and European colleagues conclude that the kind of positive population effect an overall species experiences from a loss of individuals, or mortality, depends on the size and developmental stage of the creatures that die.
If many juveniles perish, more adults are freed up to reproduce, but if more adults die, the number of juveniles that mature will increase because density dependence is relaxed, explained co-author Anieke van Leeuwen, a postdoctoral researcher in Princeton's Department of Ecology and Evolutionary Biology. Van Leeuwen worked with first author Arne Schröder, a postdoctoral research fellow at the Leibniz-Institute of Freshwater Ecology and Inland Fisheries in Berlin, and Tom Cameron, a lecturer in aquatic community ecology at the University of Essex in the United Kingdom.
This dynamic wherein the loss of individuals in one developmental stage translates to more robust individuals in another stage can be important to managing wildlife, pests or resource stocks, van Leeuwen said. For instance, targeting the adults of an invasive insect could have a counterproductive effect of making more food available to growing larvae, she said.
"It doesn't matter which developmental stage you target, if you impose mortality on one you will get overcompensation on the opposite end of the size range," van Leeuwen said. "This effect can be especially advantageous in situations where we want to manage resources we want to harvest. Knowing that there are potential effects that result in an increase in that segment of the population we want to encourage is highly relevant."
At a certain point, of course, mortality becomes too high and the species as a whole declines, the researchers report.
The researchers compared existing theoretical and experimental work on the effect of mortality on population density to resolve various inconsistencies between the two. Existing mathematical models have predicted this phenomenon, and laboratory and field studies have shown that the effect holds true for a variety of animal species.
Many ecological theories and models, however, have ignored differences in body size and development, and predicted that a modest amount of mortality would result in an increase in the total number of individuals, the researchers wrote. On the other hand, experiments have predominantly shown — along with certain models — that mortality has a positive effect within certain life stages or size classes. The researchers concluded that the overlap of experimental and theoretical data indicates that the benefit of mortality is likely divided by developmental stage. In addition, the number of species in which the phenomenon has been observed makes it commonplace in the natural world.
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The paper, "When less is more: Positive population-level effects of mortality," was published in the November 2014 issue of Trends in Ecology and Evolution.
This work was supported by the Journal of Experimental Biology; the Swedish Research Council and the Leibniz-Institute of Freshwater Ecology and Inland Fisheries; the University of Leeds, the National Environment Research Council (grant no. NE/C510467/1) and the European Commission Intra-European Fellowship (FANTISIZE, #275873); and the National Science Foundation (grant no. 1115838).
http://newsnetwork.mayoclinic.org/discus...-recovery/
EXCERPT: In an international study, Mayo Clinic researchers and collaborators have identified genetic markers that may help in identifying individuals who could benefit from the alcoholism treatment drug acamprosate. The findings, published in the journal Translational Psychiatry, show that patients carrying these genetic variants have longer periods of abstinence during the first three months of acamprosate treatment....
http://www.eurekalert.org/pub_releases/2...110414.php
ARTICLE: The puzzle pieces of tectonic plates that make up the outer layer of the earth are not rigid and don't fit together as nicely as we were taught in high school.
A study published in the journal Geology by Corné Kreemer, an associate professor at the University of Nevada, Reno, and his colleague Richard Gordon of Rice University, quantifies deformation of the Pacific plate and challenges the central approximation of the plate tectonic paradigm that plates are rigid.
Using large-scale numerical modeling as well as GPS velocities from the largest GPS data-processing center in the world – the Nevada Geodetic Laboratory at the University of Nevada, Reno – Kreemer and Gordon have showed that cooling of the lithosphere, the outermost layer of Earth, makes some sections of the Pacific plate contract horizontally at faster rates than other sections. This causes the plate to deform.
Gordon's idea is that the plate cooling, which makes the ocean deeper, also affects horizontal movement and that there is shortening and deformation of the plates due to the cooling. In partnering with Kreemer, the two put their ideas and expertise together to show that the deformation could explain why some parts of the plate tectonic puzzle didn't fall neatly into place in recent plate motion models, which is based on spreading rates along mid-oceanic ridges. Kreemer and Gordon also showed that there is a positive correlation between where the plate is predicted to deform and where intraplate earthquakes occur. Their work was supported by the National Science Foundation.
Results of the study suggest that plate-scale horizontal thermal contraction is significant, and that it may be partly released seismically. . The pair of researchers are, as the saying goes, rewriting the textbooks.
"This is plate tectonics 2.0, it revolutionizes the concepts of plate rigidity," Kreemer, who teaches in the University's College of Science, said. "We have shown that the Pacific plate deforms, that it is pliable. We are refining the plate tectonic theory and have come up with an explanation for mid-plate seismicity."
The oceanic plates are shortening due to cooling, which causes relative motion inside the plate, Kreemer said. The oceanic crust of the Pacific plate off shore California is moving 2 mm to the south every year relative to the Pacific/Antarctic plate boundary.
"It may not sound like much, but it is significant considering that we can measure crustal motion with GPS within a fraction of a millimeter per year," he said. "Unfortunately, all existing GPS stations on Pacific islands are in the old part of the plate that is not expected nor shown to deform. New measurements will be needed within the young parts of the plate to confirm this study's predictions, either on very remote islands or through sensors on the ocean floor."
This work is complementary to Kreemer's ongoing effort to quantify the deformation in all of the Earth's plate boundary zones with GPS velocities – data that are for a large part processed in the Nevada Geodetic Laboratory. The main goal of the global modeling is to convert the strain rates to earthquake forecast maps.
"Because we don't have GPS data in the right places of the Pacific plate, our prediction of how that plate deforms can supplement the strain rates I've estimated in parts of the world where we can quantify them with GPS data," Kreemer said. "Ultimately, we hope to have a good estimate of strain rates everywhere so that the models not only forecast earthquakes for places like Reno and San Francisco, but also for places where you may expect them the least."
The abstract of the article can be found here: http://geology.gsapubs.org/content/early...1.abstract.
http://www.eurekalert.org/pub_releases/2...110414.php
EXCERPT: If you took the junk from the back of your closet and combined it with the dirty laundry already on your floor, you would have an even bigger mess. While this principle will likely always hold true for our bedrooms, it turns out that in certain situations, combining messes can actually reduce the disorder of the whole. An international team of researchers from Slovenia and Iran has identified a set of conditions in which adding disorder to a system makes it more orderly. This behavior is known as antifragility, a concept introduced recently to describe similar phenomena in statistics, economics and social science....
http://www.theguardian.com/society/2014/...rain-study
EXCERPT: Working shifts significantly damages people’s ability to think and remember, and doing so for at least a decade “ages” the brain by an extra six and a half years, new research has found. The findings are the latest to link working outside normal hours to an increased risk of health problems. Other studies have suggested links with cancers, heart attacks, strokes, ulcers and metabolic diseases such as diabetes....
http://plus.maths.org/content/black-hole...x-regained
EXCERPT: [...] The black hole information paradox passed into physics folklore, with Hawking famously making a bet with Caltech's John Preskill in 1997 that black holes do obliterate information. But in 2004, Hawking conceded that his prediction had been wrong and that information could, in fact, escape — apparently resolving the paradox and sidestepping Banks, Susskind and Peskin's hot Universe problem. But Hawking never fully explained what was wrong with his original argument. [...] While Giddings thinks that Hawking was right to say that information isn't lost in black holes, he notes that we still lack a full explanation of what happens to information. To really understand how information survives, Giddings argues, we have to throw out our familiar conception of space-time...
http://theweek.com/article/index/271006/...-was-right
EXCERPT: [...] In the 12 years since this conversation (or one very much like it) sparked a million ill-informed, fantastical hit pieces on [Leo] Strauss for his insidious influence on the administration of George W. Bush, a series of Strauss' students and admirers have stepped forward to defend his work: Steven Smith, Thomas Pangle, Catherine and Michael Zuckert, Peter Minowitz.
There's much to recommend in each of these books. But for my money, the best by far is Arthur Melzer's just published study, Philosophy Between the Lines: The Lost History of Esoteric Writing. And yes, I would have come to that judgment even if I hadn't studied with the author in graduate school. Melzer has written the most compelling, surprising, and persuasive defense of Strauss's thought that I have ever read. It deserves a wide and appreciative audience. And if it gets one, the consequences could be enormous.
Because if Strauss was right in the way he interpreted the Western philosophical tradition, then much of modern scholarship — and, by extension, our civilization's understanding of its intellectual and political inheritance — will need to be radically revised....
http://chronicle.com/article/Seeking-a-C...ge/149707/
EXCERPT: [...] The American public seems, from cursory glances at headlines and polls, more divided than ever on the basic existence of climate change, in spite of scientists’ many, many warnings. Their message, the attendees fretted, simply wasn’t getting through.
This worry wasn’t just about climate change, but also stem cells. Genetically modified food. Vaccines. Nuclear power. And, of course, evolution: Challenging scientific reality seems to be an increasingly common feature of American life. Some researchers have gone so far as to accuse one political party, the Republicans, of making "science denial" a bedrock principle. The authority attributed to scientists for a century is crumbling.
It is a disturbing story. It is also, in many ways, a fairy tale. So says Dan M. Kahan, a law professor at Yale University who, over the past decade, has run an insurgent research campaign into how the public understands science. Through a magpie synthesis of psychology, risk perception, anthropology, political science, and communication research, leavened with heavy doses of empiricism and idol bashing, he has exposed the tribal biases that mediate our encounters with scientific knowledge. It’s a dynamic he calls cultural cognition....
