Post List

  • March 22, 2011
  • 01:30 PM
  • 2,089 views

On the origins of smallpox - where and when did variola virus emerge?

by Connor Bamford in The Rule of 6ix

2011 may be the year where the last known officially acknowledged stocks of the deadly smallpox virus, variola are destroyed - a virus that claimed over 500 million lives in the 20th century alone. The extensive collection of 'live' virus and DNA stocks totalling over 500 isolates/strains, which are held between the US Centres for Disease Control and the Russian State Research Centre of Virology and Biotechnology may be ordered to be eliminated following World Health Organisation (WHO) recommendations soon to be announced.
Although the impending fate of this pathogen has been covered elsewhere by Vincent Racaniello and Steven Salzberg I have been led to ponder its beginnings, at least in humans: where and when, over the course of human history did variola virus emerge  and have we always suffered from it? What confuses the matter further is that there are two clinical forms of smallpox - major (30% mortality) and minor, including both African and Alastrim minor (<1% mortality)- do these viruses have the same evolutionary history and if so, when and where did they diverge? Luckily, we can now study the origins of infectious diseases through both molecular and historical records.


A depiction of Shapona the west-African Yoruba god of smallpox. Courtesy James Gathany (photo), CDC/ Global Health Odyssey.

Conflicting historical records
It has been very confusing trying to make sense of the historical records of suspected smallpox cases as there are significant gaps in documentation and many conflicting reports. Smallpox-like skin lesions have been observed on Egyptian mummies dating from as far back as 1580 B.C yet there is no mention of the disease at all in the Old or New testaments nor even the Hippocratic texts. There was some mention of a smallpox-like disease in China and India as early as 1500 B.C but the only unmistakable description can be found from the 4th century A.D in China.  Interestingly there was no mention of smallpox in the American continents nor in sub-Saharan Africa prior to European exploration. But as shown in the picture above, smallpox has shaped west-African culture. So, did smallpox originate in Asia and spread to Egypt around 1,500 B.C? Or, is smallpox a relatively recent human disease, emerging around the 4th century A.D in Asia?
Molecular data shed light on variola evolution
A 2007 study using genomic data from the CDC's variola collections - the same ones that may soon be destroyed, added a phylogenetic perspective to the origins of smallpox and how it spread worldwide. Through studying single nucleotide polymorphisms (SNPs) from 47 variola genome isolates from geographically distant areas and collected between the 1940s and '60s they examined the genetic relatedness between isolates and were able to estimate the time since they shared a last common ancestor. They combined this DNA evidence with the above historical records to generate an idea as to where, when and how smallpox originated and spread throughout human populations.


Variola genome phylogeny

Abstract: Human disease likely attributable to variola virus (VARV), the etiologic agent of smallpox, has been reported in human populations for >2,000 years. VARV is unique among orthopoxviruses in that it is an exclusively human pathogen. Because VARV has a large, slowly evolving DNA genome, we were able to construct a robust phylogeny of VARV by analyzing concatenated single nucleotide polymorphisms (SNPs) from genome sequences of 47 VARV isolates with broad geographic distributions. Our results show two primary VARV clades, which likely diverged from an ancestral African rodent-borne variola-like virus either ≈16,000 or ≈68,000 years before present (YBP), depending on which historical records (East Asian or African) are used to calibrate the molecular clock. One primary clade was represented by the Asian VARV major strains, the more clinically severe form of smallpox, which spread from Asia either 400 or 1,600 YBP. Another primary clade included both alastrim minor, a phenotypically mild smallpox described from the American continents, and isolates from West Africa. This clade diverged from an ancestral VARV either 1,400 or 6,300 YBP, and then further diverged into two subclades at least 800 YBP. All of these analyses indicate that the divergence of alastrim and variola major occurred earlier than previously believed.




Hypothesised spread of variola worldwide

When analysed, variola fell into two large monophyletic clades signifying a historical divide in their genetic relatedness. The earliest representative - or most basal - of the variola major smallpox viruses are the Asian isolates. This suggests that major may have originated in Asia followed by geographic radiation across the Old world and into Africa. Using historical records as a means to calibrate variola evolutionary history, their results indicated that smallpox spread from Asia as much as 1,600 years ago which neatly backed up the historical records of 4th Century China. By the time smallpox reached out of East-Asia, the ancient Greek and Roman civilisations were no more - hinting that the reason they didn't observe smallpox was because at that time, in the Mediterranean region there wasn't any variola virus transmission. Despite this, analysis of the second major clade suggested a split 6,300 years ago placing variola well into ancient history. So, is smallpox a very old or relatively recent human pathogen? And, if so, where did it occur? The molecular data also showed that the clinically 'minor' forms of smallpox - African minor and Alastrim minor are very much related to the major viruses; evolutionarily speaking these viruses are thus very smilier.


A rodent origin of smallpox?... Read more »

Li, Y., Carroll, D., Gardner, S., Walsh, M., Vitalis, E., & Damon, I. (2007) From the Cover: On the origin of smallpox: Correlating variola phylogenics with historical smallpox records. Proceedings of the National Academy of Sciences, 104(40), 15787-15792. DOI: 10.1073/pnas.0609268104  

Raymond S. Weinstein. (2011) Should Remaining Stockpiles of Smallpox Virus (Variola) Be Destroyed?. Emerg Infect Dis, 17(Apr). info:/10.3201/eid1704.101865

Rimoin AW, Mulembakani PM, Johnston SC, Lloyd Smith JO, Kisalu NK, Kinkela TL, Blumberg S, Thomassen HA, Pike BL, Fair JN.... (2010) Major increase in human monkeypox incidence 30 years after smallpox vaccination campaigns cease in the Democratic Republic of Congo. Proceedings of the National Academy of Sciences of the United States of America, 107(37), 16262-7. PMID: 20805472  

  • March 22, 2011
  • 01:00 PM
  • 1,787 views

Technology with attitude

by David Bradley in Sciencetext

You might think that a smartphone is a smartphone the world over or that perceptions of tablet PCs are the same from nation to nation. Internationally, speaking, isn’t a laptop still a laptop regardless of location? A new study by researchers in the US and India suggests otherwise. The authors of the study suggest that [...]Post from: David Bradley's Sciencetext Tech TalkTechnology with attitude
... Read more »

Kallol Bagchi, Purnendu Mandal, & Arunabha Mukhopadhyay. (2011) Attitude towards technology development: a cross-cultural study of India and the USA. Int. J. Information Systems and Change Management, 5(1), 3-21. info:/

  • March 22, 2011
  • 12:52 PM
  • 1,222 views

Musical Genes

by Lorna Powell in Elements Science

Lorna Powell tunes into new research that suggests our genes could influence our enjoyment of music.



Related posts:Lung cancer gene means risk for non-smokers too
Whose gene is it anyway?
Smoking can be good for you
... Read more »

  • March 22, 2011
  • 11:18 AM
  • 1,388 views

One Nanostep for Technology, One Quantum Leap for Psychiatry

by Neurobonkers in Neurobonkers

do_sud_thumb("http://neurobonkers.com/wp-content/uploads/2011/03/computer-doctor.jpg","One Nanostep for Technology, One... Read more »

Khodayari-Rostamabad A, Reilly JP, Hasey G, Debruin H, & Maccrimmon D. (2010) Diagnosis of psychiatric disorders using EEG data and employing a statistical decision model. Conference proceedings : .. Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference, 4006-9. PMID: 21097280  

Charles DeBattista, Gustavo Kinrys, Daniel Hoffman, Corey Goldstein, John Zajecka, James Kocsis, Martin Teicher, Steven Potkin, Adrian Preda, Gurmeet Multani, Len Brandt, Mark Schiller, Dan Iosifescu, Maurizio Fava. (2011) The use of referenced-EEG (rEEG) in assisting medication selection for the treatment of depression . Psychiatric Research, 15(12), 64-75. DOI: The use of referenced-EEG (rEEG) in assisting medication selection for the treatment of depression  

  • March 22, 2011
  • 10:55 AM
  • 898 views

Cumulative Spatial Sorting: An Overlooked Evolutionary Contributor

by Michael Long in Phased

Geographical edges of species range dispersal are evolutionary focal points.... Read more »

  • March 22, 2011
  • 10:48 AM
  • 1,385 views

Be careful of what you study, how you study it, and how you write it up: the case of climate change and obesity

by Megan Carter in Verdant Nation

I happened upon an article looking at the association between obesity and climate change that was published in 2009 by the International Journal of Epidemiology (I know I am a little behind the times, but was intrigued by the title). It generated a lot of criticism from the North American public and science blogging community (examples here, here, and here). This has been mostly for good reason I think, but not always well articulated as to why. I don't believe that the authors, P. Edwards and I. Roberts of the London School of Hygiene and Tropical Medicine, set out to blame obese people for climate change, but it certainly came out that way.The study used computer modeling to compare two hypothetical populations of 1 billion people, with BMI distributions similar to the figure I quickly sketched together below.  They dubbed the one on the left the 'normal' population and the one on the right the 'overweight' population. The labeling is unfortunate because both populations do have normal weight, overweight, obese individuals, and even underweight people, just not in the same proportions. Both distributions were assumed to have the same mean height for men (1.75 m) and women (1.6 m). Writers that have critiqued this paper have argued that computer modeling is not science (and are even skeptical of the term 'Population Health'). While I disagree with that sentiment (well both actually), I don't believe that this is truly an epidemiological study either, and am somewhat surprised that IJE published this. Nonetheless, computer modeling can be made more credible with plausible assumptions and statistical tests. Unfortunately, both of these things were lacking in this study. The main aim of the paper was to estimate, rather crudely, differences in greenhouse gas (GHG) emissions from the food industry, and from car and aviation travel, between the 'normal' and 'overweight' populations. To estimate GHG emissions from the food industry, they first estimated the aggregate energy requirements for each population (to maintain weight). Basil metabolic rate was estimated using the Schofield  equations for men and women, and the activities of daily living were considered to be the same for both populations and added to BMR requirements (a simple energy in=energy out equation, which we know is not that simple).  They estimated that the overweight population required 19% more energy than the normal population. Then, based on aggregate GHG data from 2000, they estimated that this would translate into an increase of 0.27 Giga tonnes (GT) of GHG per year from the food industry alone.Okay so far? It's rather crude and for this to be somewhat credible I am assuming that the two populations are exactly the same in terms of distributions in age, height, and behaviours (which are usually not normally distributed - often depending on socioeconomic status and other factors). This 'exact sameness' between populations, other than their distribution in BMI, was not explicitly stated as far as I can tell (only an age range and mean height were given).Next, was estimation of GHG from car travel. The assumption was that extra fuel would be needed to transport a heavier population. Makes sense, but the equation for how mass affects mileage was based on a personal communication with Leonard Evans and not a published reference. If Leonard Evans is well-known in his field, great, but readers not familiar with the field (and I am just guessing Traffic Safety based on a quick Google search) need to know that this is a reputable reference.I get that if a population, on average, is heavier that fuel consumption would likely be higher for the heavier population. I don't get why two different types of cars were used to calculate the GHG emissions from driving (remember we were assuming that behaviours were the same). The normal population was assumed to have a smaller car (because they are thinner?) such as the Ford Fiesta, even though there are overweight and obese people in the normal weight population (remember that it's a distribution). The overweight population was assumed to have a larger car such as a Ford Galaxy (because they are bigger?), even though there are normal weight people in the overweight population (again it's a distribution). Larger cars emit more GHG - the Ford Galaxy emits more CO2 then the Ford Fiesta. I'm pretty sure that in North America, car choice is not totally dependent on body size (i.e. thinner, rich people still buy gas-guzzling SUVs), although I have no reference for that.The authors then go on to assume that the overweight population would walk less and drive more. Again behaviours are dependent on a lot of other things besides weight. Plus, there are overweight people in the 'normal' population, so why wouldn't they chose to drive more too? With all of these assumptions taken together, and using aggregate GHG emissions for the transportation sector as a whole, the overweight population was obviously estimated to be responsible for more GHG emissions due to car travel; 0.154 GT/y more based on 30 min/d of driving and then an added 0.019 GT/y because of deciding to take the car more often instead of walking.  Photo credit: Nika VeeBased on the assumptions of car travel, I'm surprised that the overweight population was not assumed to have chosen a larger jet for their air travel needs compared to the normal population. Alas, no, the same fuel requirements were calculated for each population with just average weight varying between the two. The authors assumed that 5% of each population would take one short-haul flight per year. This resulted in 2.038 more GT/y of GHG emissions for the overweight population. I could also turn the tables here with my own 'out-of-left-field' assumptions and say that because some airlines charge an extra seat for overweight passengers who do not fit comfortably in one seat, overweight people may be less likely to fly and therefore should not be counted in the 5%, or held responsible for extr... Read more »

Edwards P, & Roberts I. (2009) Population adiposity and climate change. International journal of epidemiology, 38(4), 1137-40. PMID: 19377099  

  • March 22, 2011
  • 10:48 AM
  • 840 views

Managing landscapes for aesthetics

by Tim De Chant in Per Square Mile

Aesthetics may have more to do with protecting land as a nature reserve than we would like to admit. Wetlands are a perfect example. Few people would consider wetlands to be “beautiful” landscapes—they offer few vistas, are difficult to navigate, and can appear rather homogeneous to the layperson. To many, a swamp is a swamp [...]... Read more »

  • March 22, 2011
  • 10:33 AM
  • 1,532 views

Finding the Family of Acrocanthosaurus

by Brian Switek in Dinosaur Tracking

Allosaurus has one of the dullest names in all of paleontology. The famous dinosaur’s moniker simply means “different reptile”—a bit of a letdown for one of the top predators of Jurassic North America. Early on, the name fit well—Allosaurus was a very unusual dinosaur compared to other large, predatory species—but since 1878 bone hunters have [...]... Read more »

  • March 22, 2011
  • 09:05 AM
  • 1,771 views

Parasitism of a different color

by Jeremy Yoder in Denim and Tweed

The common cuckoo is such a lazy parent that brood parasitism—laying its eggs in the nests of other birds—is built into its biology.

No bird will willingly adopt cuckoo chicks, which usually out-compete, and sometimes kill, their adoptive siblings. Given any hint that one of the eggs in her nest isn't hers, a bird will eject the intruder. So cuckoos have evolved eggs that mimic the coloring of their hosts' eggs—dividing the species into "host races" that specialize on a single host species, and lay eggs that mimic that host's.

.flickr-photo { }.flickr-framewide { float: right; text-align: left; margin-left: 15px; margin-bottom: 15px; width:100%;}.flickr-caption { font-size: 0.8em; margin-top: 0px; } Cuckoo eggs (indicated by arrows) in the nests of three different host species. Illustration via The Knowledge Project.As you can see from this illustration, the match is often extremely good—the cuckoo egg is really only obvious when the hosts' eggs are visibly smaller. In fact, a new study by Mary Caswell Stoddard and Martin Stevens shows that a this matching is often even better than it looks to the human eye [$a].

Birds see the world differently than humans—where we have three kinds of color-sensitive cells in our eyes, they have four. This allows them to see colors in the ultraviolet range, which is invisible to us. Birds' eyes also have an additional class of sensory cell that may help them perceive and discriminate among textures. So to study the match between cuckoo and host eggs, Stoddard and Stevens first had to figure out what each egg looked like to a bird.

.flickr-photo { }.flickr-frameright { float: right; text-align: left; margin-left: 15px; margin-bottom: 15px; width:40%;}.flickr-caption { font-size: 0.8em; margin-top: 0px; } A reed warbler feeds the cuckoo chick that has taken over its nest. Photo via Wikimedia Commons.To do this, they developed a mathematical model of each host species' vision. The model estimated how similar two eggs should look to a bird, given raw data about what colors of light the eggs reflect and the specific colors the bird can detect. Using the model, Stoddard and Stevens could then calculate the "overlap" between the colors and patterning of a host egg and the egg of a cuckoo specializing on that host species.

Stoddard and Stevens then applied the vision model's measure of similarity to museum specimens of eggs from the cuckoo-parasitized nests of eleven European bird species. They found that cuckoo eggs matched their hosts' quite well overall, but the match was best for cuckoos specialized on especially vigilant hosts. For each host, the authors looked up studies of egg rejection behaviors to calculate the probability that each species would eject eggs that didn't look like their own. Species with higher ejection probabilities were parasitized by cuckoo host races whose eggs were better mimics.

That suggests host rejection behavior exerts strong natural selection on cuckoos, which makes sense given that successfully fooling a host is essential to cuckoo reproduction. In light of evidence that cuckoos can also exert selection on their hosts, it looks as though brood parasitism is a truly coevolutionary interaction between cuckoos and their hosts—one that can cause both to evolve greater diversity.

Reference

Stoddard, M., & Stevens, M. (2011). Avian vision and the evolution of egg color mimicry in the common cuckoo. Evolution DOI: 10.1111/j.1558-5646.2011.01262.x

... Read more »

  • March 22, 2011
  • 09:03 AM
  • 1,817 views

moving one inch closer to real world wetware

by Greg Fish in weird things

One of the classic ideas in science fiction is the concept of wetware, a hybrid of biology and electronics which would allow just about any living thing with a brain to hook up to a machine and carry out computing tasks we could never accomplish solely with brains or solely with machinery. As noted last [...]... Read more »

Yu, M., Huang, Y., Ballweg, J., Shin, H., Huang, M., Savage, D., Lagally, M., Dent, E., Blick, R., & Williams, J. (2011) Semiconductor Nanomembrane Tubes: Three-Dimensional Confinement for Controlled Neurite Outgrowth. ACS Nano, 2147483647. DOI: 10.1021/nn103618d  

  • March 22, 2011
  • 09:00 AM
  • 1,689 views

Injury Patterns in Overweight and Obese High School Athletes

by Arya M. Sharma in Dr. Sharma's Obesity Notes

In case readers are wondering whether the term “obese athlete” is an oxymoron, it is not: from my own practice I know that there are a number of high-performance athletes out there, who can have significant weight-related health problems including obstructive sleep apnea, hypertension and fatty liver disease. But that is NOT the topic of [...]... Read more »

Yard E, & Comstock D. (2011) Injury Patterns by Body Mass Index in US High School Athletes. Journal of physical activity , 8(2), 182-91. PMID: 21415445  

  • March 22, 2011
  • 09:00 AM
  • 1,056 views

Bacterial Burlargy

by Kevin Bonham in Food Matters

I feel like I've seen this movie before. A group of thieves need to gain entry to a highly secured vault. The vault door is nearly impregnable, and once inside, there are motion sensors, security cameras and laser trip lines, all of which sound the alarm. When the security guards hear what's happening, they are told to release a deadly gas into the vault, killing anyone inside. But Salmonella enterica, that charming bug responsible for all manner of unpleasantness, is a clever burglar. It has learned to live inside macrophages - cells that are usually used to destroy bugs - and uses their own defenses against them.

The first step is getting inside, but when the cell is designed to eat bugs, this isn't much of a feat. Macrophages express a number of receptors that latch onto bacteria, viruses and all manner of dangerous things to pull them inside. But this thief wants to be caught, all it has to do is get near a macrophage, and it will be engulfed. The thieves just turn themselves in, knowing the guards will try to secure them in the vault. It's the next step that's tricky. Once macrophages engulf something, it is enclosed in a membrane-bound vesicle called a phagosome, which rapidly begins a transformation process. Everything inside is destined for destruction, so the phagosome begins to pump in protons, increasing the acidity. This is pretty inhospitable by itself, but acidification also activates enzymes designed to destroy any and all molecules they find.

Acidification itself is triggered by the receptors of the innate immune system, especially Toll-like receptors. TLR3, 7 and 9 have all been shown to contribute to clearing Salmonella. Not surprisingly, if you knock out one or two of these receptors, infection with these bugs is far more deadly. But researchers at UC Berkeley noticed something strange - if you knock out all three, mice are protected. In other words, if you disable the security cameras, motion sensors AND laser trip lines, the thieves can't finish the heist. How does that make any sense?

TLR Signaling Is Required for Salmonella typhimurium Virulence
Read the rest of this post... | Read the comments on this post...... Read more »

Arpaia N, Godec J, Lau L, Sivick KE, McLaughlin LM, Jones MB, Dracheva T, Peterson SN, Monack DM, & Barton GM. (2011) TLR Signaling Is Required for Salmonella typhimurium Virulence. Cell, 144(5), 675-88. PMID: 21376231  

  • March 22, 2011
  • 08:00 AM
  • 1,004 views

Brain Starvation and Why It Is Important

by Shaheen Lakhan in Brain Blogger

Alzheimer’s disease (AD) currently afflicts more than 5 million Americans and healthcare costs for those who will be affected in 2050 are predicted to surpass one trillion dollars! It is a disease that takes away uniquely human traits and for which there is no cure. In addition, there appears to be little that we can [...]... Read more »

  • March 22, 2011
  • 08:00 AM
  • 1,213 views

Tuesday Crustie: Indiscriminate?

by Zen Faulkes in NeuroDojo

Male fiddler crabs spend a lot of time doing this sort of thing:


This is Uca mjoebergi, a colourful crab from south Pacific shores. They're signalling to someone - but to whom?. To their own species? Their own sex? To predators?

I had fun recently giving a talk about fiddler crab signalling at a local nature center. I had seen a decent amount of research on fiddler crabs, but had never had the opportunity to review it and try to pull it into a story before. And while I was doing that, a new paper appeared about fiddler crabs.

While you're preparing talk on something, new research gets published. It's a variation of the law of maximum inconvenience.

One of the problems with signalling is that it implies that there is some sort of intended audience. Spending your time and energy waving a lot can be worth it if your intended audience is always nearby.

In this case, this nicely coloured species, Uca mjoebergi, the males' audience is mainly females of the same species. In most of the range of this species, it's the only fiddler crab in the environment. But in some locations, there are a couple of other fiddler crab species. Some of them look distinctly different to us, but fiddler crabs' eyes don't have the same power as us.

Could the males of this species tell the females apart? Or would they be all, like, "Hey baby... hey baby... hey baby..." to any vaguely crab-like shape that was nearby?

The answer was... it depends.

When single females were released into a colony of U. mjoebergi males, the males waved regardless of whether it was a U. mjoebergi female (smooth moves!) or U. signata female (sorry, but you're not really my type).

Femalesof both species were also presented simultaneously, but in a slightly less natural scenario. Instead of females walking of their own volition through the colony, they were tethered so they wouldn't move out of range of a male's burrow. Booksmyth and colleagues also put up barriers so that males wouldn't be able to see other distractions.

Under these conditions, the males would often wave at both females... but they would wave longer and faster to the females of the same species, and were much more likely to try to mate with the female of the right species. But the match wasn't perfect; some males still tried to mate with the wrong species. Interspecies harassment, if you will.

This suggests that the guys can tell if the girl is the right species. So why don't they, especially if waving is costly?

One possibility is that by having the males generally waving regardless of species, a male colony might become almost like a lek or mating "hotspot" that attracts more females of the right species.

Another interesting one is that the females can tell the males apart better then the males recognize females. The females might "reject" inappropriate males so quickly that the cost to the male is minimized.

Finally, the mix of "right species" to "wrong species" might matter. The "right species" was far more prominent in this area. An interesting follow-up would be to repeat these experiments in a place where the "right species" was in the minority, and males might waste a lot more time and energy courting indiscriminately.

Reference

Booksmythe I, Jennions M, & Backwell P. 2011. Male fiddler crabs prefer conspecific females during simultaneous, but not sequential, mate choice. Animal Behaviour: In press. DOI: 10.1016/j.anbehav.2011.01.009

Photo from here.... Read more »

  • March 22, 2011
  • 07:47 AM
  • 1,125 views

Low-energy effective Yang-Mills theory

by Marco Frasca in The Gauge Connection

As usual I read the daily from arxiv and often it happens to find very interesting papers. This is the case for a new paper from Kei-Ichi Kondo. Kondo was in Ghent last year (here his talk) and I have had the chance to meet him. His research is on very similar lines as mine. [...]... Read more »

Marco Frasca. (2010) Glueball spectrum and hadronic processes in low-energy QCD. Nucl.Phys.Proc.Suppl.207-208:196-199,2010. arXiv: 1007.4479v2

Marco Frasca. (2008) Infrared QCD. International Journal of Modern Physics E 18, (2009) 693-703. arXiv: 0803.0319v5

Attilio Cucchieri, & Tereza Mendes. (2009) Landau-gauge propagators in Yang-Mills theories at beta . Phys.Rev.D81:016005,2010. arXiv: 0904.4033v2

  • March 22, 2011
  • 07:43 AM
  • 1,050 views

The Extinction of Religion?

by The Twenty-first floor in The Twenty-first floor

Keir Liddle explores the idea, put forward in a paper published online, that in nine countries religion may face extinction.... Read more »

Daniel M. Abrams, Haley A. Yaple, & Richard J. Wiener. (2010) A mathematical model of social group competition with application to the growth of religious non-affiliation. Physics and Society. arXiv: 1012.1375v2

  • March 22, 2011
  • 03:00 AM
  • 857 views

Brains plus beauty don’t add up: objectifying women lowers their math performance

by SAGE Insight in SAGE Insight

When what you see is what you get: the consequences of the objectifying gaze for women and men From Psychology of Women Quarterly Women who are looked at as sexual objects not only react as sexual objects, they also exhibit less proficiency with math, according to this research. Undergraduates from a large Midwestern university were [...]... Read more »

  • March 22, 2011
  • 02:19 AM
  • 1,539 views

Ten Tips for Adult Learning

by Dr Shock in Dr Shock MD PhD


These ten tips are from an article for surgeons but the ten tips are also applicable for all forms of adult education. Especially in training residents the hidden curriculum and ad hoc events occurring in a convenient pause in the hectic daily activity are important educational encounters. In this day and age medical training should [...]


No related posts.... Read more »

  • March 21, 2011
  • 09:59 PM
  • 1,975 views

Unintentional Shark Tagging

by Chuck in Ya Like Dags?

This might possibly be the most awesome paper about tagging fish ever. One of the handiest advances in telemetry, especially of large, highly-migratory oceanic species, has been the advent of SPOT tags.  These tags do it all: movement, depth, temperature, … Continue reading →... Read more »

David W. Kerstetter, Jeffery J. Polovina, & John E. Graves. (2004) Evidence of shark predation and scavenging on fishes equipped with pop-up satellite archival tags. Fishery Bulletin, 750-756. info:/

  • March 21, 2011
  • 09:33 PM
  • 2,572 views

From the Editor’s Desk: The Environmental Impacts of Tsunamis

by Dr. M in Deep Sea News

Figure from UNEP: These images show a combination of a rocky, hilly headland along with a small river delta and swampy coastal strip. A low-lying wetland area connects the northern and western ocean fronts. An integration of natural and agricultural ecosystems operating prior to the tsunami combined rice cultivation, and fish/shrimp ponds, alongside natural delta mangrove . . . → Read More: From the Editor’s Desk: The Environmental Impacts of Tsunamis... Read more »

join us!

Do you write about peer-reviewed research in your blog? Use ResearchBlogging.org to make it easy for your readers — and others from around the world — to find your serious posts about academic research.

If you don't have a blog, you can still use our site to learn about fascinating developments in cutting-edge research from around the world.

Register Now

Research Blogging is powered by SMG Technology.

To learn more, visit seedmediagroup.com.