Blog Pick Of The Month – August 2010

There were 28 blog posts covering PLoS ONE articles aggregated on ResearchBlogging.org in August. And there was a wealth of really good ones to choose from. Even when I narrowed it down to five, it was difficult – they are equally good. So I changed my mind several times over the past few days. But choose I must, so here it is.

The winner in August is Michelle of the C6-H12-O6 blog, for her post Pushing towards acknowledging sex differences in physiology and treatment efficacy describing the work in the PLoS ONE article Differences in Efficacy and Safety of Pharmaceutical Treatments between Men and Women: An Umbrella Review by Gerald Gartlehner, Andrea Chapman, Michaela Strobelberger and Kylie Thaler from the Department for Evidence-Based Medicine and Clinical Epidemiology, Danube University Krems, Krems, Austria.

From the Abstract of the paper:

Being male or female is an important determinant of risks for certain diseases, patterns of illness and life expectancy. Although differences in risks for and prognoses of several diseases have been well documented, sex-based differences in responses to pharmaceutical treatments and accompanying risks of adverse events are less clear. The objective of this umbrella review was to determine whether clinically relevant differences in efficacy and safety of commonly prescribed medications exist between men and women. We retrieved all available systematic reviews of the Oregon Drug Effectiveness Review Project published before January 2010. Two persons independently reviewed each report to identify relevant studies. We dually abstracted data from the original publications into standardized forms. We synthesized the available evidence for each drug class and rated its quality applying the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Findings, based on 59 studies and data of more than 250,000 patients suggested that for the majority of drugs no substantial differences in efficacy and safety exist between men and women. Some clinically important exceptions, however, were apparent: women experienced substantially lower response rates with newer antiemetics than men (45% vs. 58%; relative risk 1.49, 95% confidence interval 1.35–1.64); men had higher rates of sexual dysfunction than women while on paroxetine for major depressive disorder; women discontinued lovastatin more frequently than men because of adverse events. Overall, for the majority of drugs sex does not appear to be a factor that has to be taken into consideration when choosing a drug treatment. The available body of evidence, however, was limited in quality and quantity, confining the range and certainty of our conclusions.

In her blog post, Michelle says:

It is no surprise to many people that men and women are sometimes more susceptible to certain diseases than the other. By virtue of having differing anatomy, physiology, and gender expectations, we are going to be prone to different types of diseases, injuries, syndromes, and whatever-you-call-its. That being said, the majority of pathologies affect both men and women relatively equally. Despite that fact, rarely do clinical trials explore the difference in response to treatments based on sex. In 2008, Phyllis Greenberger wrote a letter to Science, Flaunting the Feminine Side of Research Studies, lamenting the fact that more studies didn’t explore the effect of sex as a variable on treatment efficacy.

I am about to notify both Michelle and the authors of the article and send them the famous PLoS ONE t-shirts as prizes.

This month’s runners-up are: Dormivigilia, DeLene Beeland, Southern Fried Scientist and Brian Switek.

Previous winners:

March 2009: Ed Yong April 2009: Eric Michael Johnson May 2009: Christie Wilcox June 2009: Iddo Friedberg July 2009: Toaster Sunshine and Hermitage August 2009: Bjoern Brembs September 2009: Alun Salt October 2009: Andrew Farke November 2009: John Beetham December 2009: SciCurious January 2010: Anne-Marie Hodge February 2010: Princess Ojiaku March 2010: Grrrlscientist April 2010: Jason Goldman May 2010: Brian Switek June 2010: Greg Laden July 2010: Hannah Waters

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Worth a Thousand Words

Cells need to be able to stick to each other in order to form tissues and organs of multicellular organisms. Without the process of cell adhesion, multicellular life would be impossible. When cells that are supposed to stick with each other don’t, or when cells that are not supposed to stick to each other do so, we are facing serious diseases and disorders. Understanding the mechanism of cell adhesion is thus necessary for improving treatments of such disorders.

The term ‘cellular adhesion’ is used not just for the phenomenon of cells binding to each other, but also for the binding of a cell to a natural of artfiicial surface or an extracellular matrix. This has been used in organ transplantation and, more recently, in biotechnology – production of artificial tissues for transplantation.

A number of natural and artificial materials have been tested as potential scaffolding for such bioengineered tissues. Silk from the silkworm is good, but tends to trigger an immune response. Silk from spiders, on the other hand, is readily accepted by the host and its mechanical properties make it a potentially superior material. Data to date are equivocal as to the ability of the cells to adhere to the spider silk and to further divide and spread.

In Interactions between Spider Silk and Cells – NIH/3T3 Fibroblasts Seeded on Miniature Weaving Frames by Joern W. Kuhbier, Christina Allmeling, Kerstin Reimers, Anja Hillmer, Cornelia Kasper, Bjoern Menger, Gudrun Brandes, Merlin Guggenheim and Peter M. Vogt raised some spiders and then milked them for silk, placing the silk in regular, geometrically simple patterns on a frame. They then photographed the cells (and controls, on other substrates) with several different microscopy and photography methods over a period of several days. What they discovered is that cells immediatelly and readily stick to the spider silk and further proliferate.

But this post is about the images, right? So here are some of the beautiful pictures of the cells (fibroblasts) adhering to the spider silk, as seen under various kinds of microscopes:




From the Abstract:

Background

Several materials have been used for tissue engineering purposes, since the ideal matrix depends on the desired tissue. Silk biomaterials have come to focus due to their great mechanical properties. As untreated silkworm silk has been found to be quite immunogenic, an alternative could be spider silk. Not only does it own unique mechanical properties, its biocompatibility has been shown already in vivo. In our study, we used native spider dragline silk which is known as the strongest fibre in nature.

Methodology/Principal Findings

Steel frames were originally designed and manufactured and woven with spider silk, harvesting dragline silk directly out of the animal. After sterilization, scaffolds were seeded with fibroblasts to analyse cell proliferation and adhesion. Analysis of cell morphology and actin filament alignment clearly revealed adherence. Proliferation was measured by cell count as well as determination of relative fluorescence each after 1, 2, 3, and 5 days. Cell counts for native spider silk were also compared with those for trypsin-digested spider silk. Spider silk specimens displayed less proliferation than collagen- and fibronectin-coated cover slips, enzymatic treatment reduced adhesion and proliferation rates tendentially though not significantly. Nevertheless, proliferation could be proven with high significance (p<0.01).

Conclusion/Significance

Native spider silk does not require any modification to its application as a biomaterial that can rival any artificial material in terms of cell growth promoting properties. We could show adhesion mechanics on intracellular level. Additionally, proliferation kinetics were higher than in enzymatically digested controls, indicating that spider silk does not require modification. Recent findings concerning reduction of cell proliferation after exposure could not be met. As biotechnological production of the hierarchical composition of native spider silk fibres is still a challenge, our study has a pioneer role in researching cellular mechanics on native spider silk fibres.

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Media Coverage of the Marine Biodiversity and Biogeography Collection

The newest PLoS ONE Collection, Marine Biodiversity and Biogeography – Regional Comparisons of Global Issues, has attracted huge global coverage in the media. Here, we (Jen Laloup and I, but WordPress does not allow for two-author posts) will try to highlight some of that coverage:

AP
The Age
Suite 101
ASNS News (Africa)
Philadelphia Inquirer
AFP
Mongabay.com
The Australian
ABC News
Asylum (blog)
Time.com
The Telegraph (Calcutta, India
Global Adventures
Top News (UK)
Care2 (blog)
The Vancouver Sun
Scientific American
Cosmos Magazine
Denver Post.com
Deep Sea News (blog)

[youtube=http://www.youtube.com/watch?v=7bNKHb1b0p8]

Channel 4 News
Spiegel Online International
redOrbit
The Globe and Mail
The Guardian
3 News.co.uk
G1 Globo (Brazil)
Presseurop
ITN
Radio New Zealand News
Fort Worth Star Telegram
Newser
FOX.com
Tonic
Treehugger
Our Amazing Planet
Estadão
Marine Public Broadcasting Network
Metro
The Hindu (India)
The Daily Yomiuri (Japan)
Digital Journal

[youtube=http://www.youtube.com/watch?v=n7Fwe-L2y7w]

ScienceNews (US News and World Report)
The Guardian (UK)
UPI.com
Times Colonist (Canada)
CNN International
CTV (Canada)
CBS News
The Telegram
MSNBC.com
Independent.ie
Practical Fishkeeping
BBC
Telegraph (UK)
Haaretz (Israel)
Hindustan Times (India)
The Courier-Mail (Australia)
Dailymail.com
Reuters
VOA
Associated Press
National Geographic
National Geographic video
Nature News
ABC News (Australia)
Mirror.co.uk
Domain-b
Conservation Magazine
ScienceNews
Science Codex
Lab Spaces
Science Centric
Life, Nature, Conservation from USA
BioEthics Hawaii
EveryDay Science
Mola mola
Green Antilles
RFF Library Blog

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Monthly PLoS ONE News and Blog Round-Up

Events interfered, so I could not collect the media coverage every week. So today here is the entire month! We’ll return to weekly coverage next month.

In this month’s PLoS ONE media digest: biased refereeing in soccer, strong-armed sabertooth tigers, lefty politicians, what makes farmed salmon sick, sex makes brains grow, and more….


Continue reading »

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Blog Pick Of The Month – July 2010

July is summertime, when people go offline to enjoy the weather and travel, but intrepid bloggers cannot be stopped! There were 30 blog posts covering PLoS ONE articles aggregated on ResearchBlogging.org in July. And as always, really good and hard to choose from. But choose I must! This month’s winner is….

….Hannah Waters of the Culturing Science blog (with the subtitle “biology as relevant to us earthly beings”), for her post Forest canopy height: why do we care?, describing the research in the PLoS ONE aticle Recent Widespread Tree Growth Decline Despite Increasing Atmospheric CO2 by Lucas C. R. Silva, Madhur Anand and Mark D. Leithead of the Global Ecological Change Laboratory in the School of Environmental Sciences at the University of Guelph in Ontario, Canada. From the Abstract of the paper:

Background

The synergetic effects of recent rising atmospheric CO2 and temperature are expected to favor tree growth in boreal and temperate forests. However, recent dendrochronological studies have shown site-specific unprecedented growth enhancements or declines. The question of whether either of these trends is caused by changes in the atmosphere remains unanswered because dendrochronology alone has not been able to clarify the physiological basis of such trends.

Methodology/Principal Findings

Here we combined standard dendrochronological methods with carbon isotopic analysis to investigate whether atmospheric changes enhanced water use efficiency (WUE) and growth of two deciduous and two coniferous tree species along a 9° latitudinal gradient across temperate and boreal forests in Ontario, Canada. Our results show that although trees have had around 53% increases in WUE over the past century, growth decline (measured as a decrease in basal area increment – BAI) has been the prevalent response in recent decades irrespective of species identity and latitude. Since the 1950s, tree BAI was predominantly negatively correlated with warmer climates and/or positively correlated with precipitation, suggesting warming induced water stress. However, where growth declines were not explained by climate, WUE and BAI were linearly and positively correlated, showing that declines are not always attributable to warming induced stress and additional stressors may exist.

Conclusions

Our results show an unexpected widespread tree growth decline in temperate and boreal forests due to warming induced stress but are also suggestive of additional stressors. Rising atmospheric CO2 levels during the past century resulted in consistent increases in water use efficiency, but this did not prevent growth decline. These findings challenge current predictions of increasing terrestrial carbon stocks under climate change scenarios.

In her blog post, Hannah says:

Lasers are cool! The LIDAR technology, originally created for studying atmospheric chemistry, reapplied to study canopy heights has allowed us to visualize our forests in a new way. (And make some beautiful pictures.) There was a lot of work put into it – and to accurately measure how our forests are changing, increasing work will have to be done to keep the maps updated to create an index of canopy height on our planet.

However, we’ve also learned that we cannot necessarily rely on traditional hypotheses in times of climate change. While trees have the capacity to remove carbon from the atmosphere and store it, other factors can confound these effects, as we read in the PLoS ONE paper. While more work certainly needs to be done on this front (using large-scale climate measures for growth instead of dendrochronology, for example), their results are certainly sobering.

I am about to notify both Hannah and the authors of the article and send them the famous PLoS ONE t-shirts as prizes. This month’s runners-up are: EcoPhysioMichelle, for blogging not one but three PLoS ONE articles last month (one, two, three), Neurosceptic (two posts – one, two), and the trio of bloggers – Kevin Zelnio, Razib Khan and Dave Munger – for discussing one of the PLoS ONE articles in their weekly podcast.

Previous winners:

March 2009: Ed Yong
April 2009: Eric Michael Johnson
May 2009: Christie Wilcox
June 2009: Iddo Friedberg
July 2009: Toaster Sunshine and Hermitage
August 2009: Bjoern Brembs
September 2009: Alun Salt
October 2009: Andrew Farke
November 2009: John Beetham
December 2009: SciCurious
January 2010: Anne-Marie Hodge
February 2010: Princess Ojiaku
March 2010: Grrrlscientist
April 2010: Jason Goldman
May 2010: Brian Switek
June 2010: Greg Laden

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Blog Pick of the Month – June 2010

June 2010 just ended, so it’s time for the PLoS ONE Blog Pick Of The Month.

There were 28 blog posts covering PLoS ONE articles aggregated on ResearchBlogging.org in June. And as always, they were great fun to read. This month’s winner is….

Greg Laden of the eponymous blog, for his post How did the victims of the Plinean Eruption of Vesuvius die? describing and explaining the research in the PLoS ONE article Lethal Thermal Impact at Periphery of Pyroclastic Surges: Evidences at Pompeii by Giuseppe Mastrolorenzo, Pierpaolo Petrone, Lucia Pappalardo and Fabio M. Guarino of Napoli, Italy. The paper’s Abstract states:

Background

The evaluation of mortality of pyroclastic surges and flows (PDCs) produced by explosive eruptions is a major goal in risk assessment and mitigation, particularly in distal reaches of flows that are often heavily urbanized. Pompeii and the nearby archaeological sites preserve the most complete set of evidence of the 79 AD catastrophic eruption recording its effects on structures and people.

Methodology/Principal Findings

Here we investigate the causes of mortality in PDCs at Pompeii and surroundings on the bases of a multidisciplinary volcanological and bio-anthropological study. Field and laboratory study of the eruption products and victims merged with numerical simulations and experiments indicate that heat was the main cause of death of people, heretofore supposed to have died by ash suffocation. Our results show that exposure to at least 250°C hot surges at a distance of 10 kilometres from the vent was sufficient to cause instant death, even if people were sheltered within buildings. Despite the fact that impact force and exposure time to dusty gas declined toward PDCs periphery up to the survival conditions, lethal temperatures were maintained up to the PDCs extreme depositional limits.

Conclusions/Significance

This evidence indicates that the risk in flow marginal zones could be underestimated by simply assuming that very thin distal deposits, resulting from PDCs with poor total particle load, correspond to negligible effects. Therefore our findings are essential for hazard plans development and for actions aimed to risk mitigation at Vesuvius and other explosive volcanoes.

In his blog post, Greg Laden writes:

Consider this: Imagine an area about 10 kilometers (just over 6 miles) around the volcano. Now imagine that area being covered with a blanket of very hot ashy air over the course of about 3 minutes. To help imagine this, pretend you are looking at the volcano when the explosion starts, and there is an airliner over the volcano heading for you at the same time. It is moving at top speed for such an aircraft, and when it reached you it has slowed to just over 100 mph. That represents the leading edge of the blanket of hot air and ash. Just at that moment, the blanket of air and ash deflates/dissipates, the air cooling and the ash settling. But first, all humans, probably all tetrapods (birds, mammals, etc) within that few miles of space have simply dropped dead. Since there is only a little ash, they are dirtied by it, but later, a larger deposit of ash is spewed out, and now all the dead are deeply buried.

Oh, and there is a video!

I am about to notify both Greg and the authors of the article and send them the famous PLoS ONE t-shirts as prizes. This month’s runners-up are: Hannah Waters, Charles Daney and Darcy Cowan.

Previous winners:

March 2009: Ed Yong
April 2009: Eric Michael Johnson
May 2009: Christie Wilcox
June 2009: Iddo Friedberg
July 2009: Toaster Sunshine and Hermitage
August 2009: Bjoern Brembs
September 2009: Alun Salt
October 2009: Andrew Farke
November 2009: John Beetham
December 2009: SciCurious
January 2010: Anne-Marie Hodge
February 2010: Princess Ojiaku
March 2010: Grrrlscientist
April 2010: Jason Goldman
May 2010: Brian Switek

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Weekly PLoS ONE News and Blog Round-Up

In this week’s PLoS ONE media digest: soccer, Komod dragons, Vesuvius erruption, ants using Velcro, organic pesticides, cancer diagnosis by digital camera, and much more:

Quantifying the Performance of Individual Players in a Team Activity by Duch et al, was covered by UPI, Washington Post, National Geographic, Chicago Sun-Times, Forbes, MSNBC, Media Newswire, AP, LiveScience and AFP.

Deathly Drool: Evolutionary and Ecological Basis of Septic Bacteria in Komodo Dragon Mouths by Bull et al., was blogged by NeuroDojo, Neurotopia, Mike the Mad Biologist and right here at everyONE.

Lethal Thermal Impact at Periphery of Pyroclastic Surges: Evidences at Pompeii by Mastrolorenzo et al, was covered by Greg Laden, io9 and here at everyONE blog.

Arboreal Ants Use the “Velcro® Principle” to Capture Very Large Prey, by Dejean et al, was covered by Ars Technica, LiveScience and Wired Science.

Choosing Organic Pesticides over Synthetic Pesticides May Not Effectively Mitigate Environmental Risk in Soybeans by Bahlai et al, was covered at CBC, GuelphNow, Alberta Express, Nutritional Blogma, Sify news, Phased and Journal Watch Online.

A Fiber-Optic Fluorescence Microscope Using a Consumer-Grade Digital Camera for In Vivo Cellular Imaging by Shin et al, was covered at Medician.info, Scope, ShutterVoice, UPI, HealthJockey, DNAIndia and OneIndia.

Location-Specific Responses to Thermal Stress in Larvae of the Reef-Building Coral Montastraea faveolata by Polato et al, was highlited in Physorg, UPI and Our Amazing Planet.

Do Ravens Show Consolation? Responses to Distressed Others by Fraser and Bugnyar was covered at Living the Scientific Life and Scepticon

A Locomotor Innovation Enables Water-Land Transition in a Marine Fish by Hsieh was discussed at NeuroDojo.

The Brain Functional Networks Associated to Human and Animal Suffering Differ among Omnivores, Vegetarians and Vegans by Filippi et al., was covered at Scepticon (NZ sciblogs), Scepticon and The Neurocritic.

Methicillin Resistant Staphylococcus aureus ST398 in Veal Calf Farming: Human MRSA Carriage Related with Animal Antimicrobial Usage and Farm Hygiene by Graveland et al., was covered by Emerging Health Threats Forum.

Sexual Dimorphism of the Zebra Finch Syrinx Indicates Adaptation for High Fundamental Frequencies in Males by Riede et al, was covered by Salt Lake Tribune and RedOrbit.

The Political Gender Gap: Gender Bias in Facial Inferences that Predict Voting Behavior by Chiao et al, was covered at The Psychology of Beauty.

Metabolic State Alters Economic Decision Making under Risk in Humans by Symmonds et al, was covered at Economix (NYTimes blog).

Rhythmicity in Mice Selected for Extremes in Stress Reactivity: Behavioural, Endocrine and Sleep Changes Resembling Endophenotypes of Major Depression by Touma et al, was covered at Brain Posts.

Thinking Outside a Less Intact Box: Thalamic Dopamine D2 Receptor Densities Are Negatively Related to Psychometric Creativity in Healthy Individuals by de Manzano et al, was covered at Science and Reason.

The discussion of Prestige Affects Cultural Learning in Chimpanzees by Horner et al, continues on The Primate Diaries and HealthCanal.

Evolution of DNA Replication Protein Complexes in Eukaryotes and Archaea by Chia et al, was covered by Lab Rat.

Marine Reserves Enhance the Recovery of Corals on Caribbean Reefs by Mumby and Harborne, was covered at Ars Technica.

Can Preening Contribute to Influenza A Virus Infection in Wild Waterbirds? by Delogu et al, was covered at Journal Watch Online and CIDRAP.

Evolutionary Dead End in the Galápagos: Divergence of Sexual Signals in the Rarest of Darwin’s Finches by Brumm et al, was covered at Ars Technica.

Testing Evolutionary and Dispersion Scenarios for the Settlement of the New World by Hubbe et al, was discussed on Anthropology.net, Softpedia and ScienceNOW.

Integrative Approach to Quality Assessment of Medical Journals Using Impact Factor, Eigenfactor, and Article Influence Scores by Rizkallah and Sin was referred to at O’Really?

The Lagoon at Caroline/Millennium Atoll, Republic of Kiribati: Natural History of a Nearly Pristine Ecosystem by Barott et al, was covered at Practical Fishkeeping.

Detection of Large Numbers of Novel Sequences in the Metatranscriptomes of Complex Marine Microbial Communities by Gilbert et al, was blogged by Lab Rat.

Metabolic State Alters Economic Decision Making under Risk in Humans by Symmonds et al., was covered at BPS Research Digest.

Serum S100B: A Potential Biomarker for Suicidality in Adolescents? by Falcone et al, was noted by Phased.

CD8+ T Cell Priming by Dendritic Cell Vaccines Requires Antigen Transfer to Endogenous Antigen Presenting Cells by Yewdall et al, was blogged at Mystery Rays from Outer Space.

Phytoplankton Biogeography and Community Stability in the Ocean by Cermeno et al, was covered by Culturing Science.

Ecosystem Carbon Stock Influenced by Plantation Practice: Implications for Planting Forests as a Measure of Climate Change Mitigation by Liao et al, was covered by Conservation Maven.

Coevolution in Action: Disruptive Selection on Egg Colour in an Avian Brood Parasite and Its Host by Yang et al, was discusses on Denim and Tweed.

Genetic Divergence across Habitats in the Widespread Coral Seriatopora hystrix and Its Associated Symbiodinium by Bongaerts et al, was covered in Practical Fishkeeping.

Lowering β-Amyloid Levels Rescues Learning and Memory in a Down Syndrome Mouse Model by Netzer et al, was blogged on Phased.

Marginal Eyespots on Butterfly Wings Deflect Bird Attacks Under Low Light Intensities with UV Wavelengths by Olofsson et al, was covered by Conservation Maven.

SUBTLEX-CH: Chinese Word and Character Frequencies Based on Film Subtitles by Cai and Brysbaert was written about by Greg Laden.

Comparative Influence of Ocean Conditions on Yellowfin and Atlantic Bluefin Tuna Catch from Longlines in the Gulf of Mexico by Tao and Block was covered at Living the Scientific Life.

Follow-Up of Patients with Multidrug Resistant Tuberculosis Four Years after Standardized First-Line Drug Treatment by He et al, was covered by International Health Research.

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Worth a Thousand Words

Komodo dragons are fascinating creatures – they are huge, they are aggressive and dangerous, and they are venomous! But they also have bacteria in their mouths and it was hypothesized, especially before the venom was discovered, that the bacteria play a role in killing the prey that managed to escape the first time it is attacked.

In last week’s PLoS ONE article, Deathly Drool: Evolutionary and Ecological Basis of Septic Bacteria in Komodo Dragon, authors Bull, Jessop and Whiteley investigate the mouth bacteria in Komodo dragons, the different species found in mouths of different individuals, and the way bacteria get transmitted from one individual to another.

By outfitting Komodo dragons with radio-collars, observing their behavior and identifying bacteria in their saliva and on their killed prey, they concluded that large pray carcasses act as giant petri dishes for bacteria. It takes a long time for a large animal to get eaten by the lizards, and each such carcass is eaten by multiple individual lizards over time. This is sufficient time for bacteria from the first lizard’s saliva to grow on the carcass and then ‘infect’ the mouths of subsequent lizards. The large carcasses are thus a means for bacteria to spread from one individual to another. And this mostly happens in large Komodo dragons, as small individuals tend to kill small prey that is eaten too rapidly for any bacteria to get established.

Of course, the photographs of Komodo dragons chasing the pray, and then eating the kill, are fascinating:


For more details about the study, read the excellent blog posts on Neurotopia and NeuroDojo.

From the article’s Abstract:

Komodo dragons, the world’s largest lizard, dispatch their large ungulate prey by biting and tearing flesh. If a prey escapes, oral bacteria inoculated into the wound reputedly induce a sepsis that augments later prey capture by the same or other lizards. However, the ecological and evolutionary basis of sepsis in Komodo prey acquisition is controversial. Two models have been proposed. The “bacteria as venom” model postulates that the oral flora directly benefits the lizard in prey capture irrespective of any benefit to the bacteria. The “passive acquisition” model is that the oral flora of lizards reflects the bacteria found in carrion and sick prey, with no relevance to the ability to induce sepsis in subsequent prey. A third model is proposed and analyzed here, the “lizard-lizard epidemic” model. In this model, bacteria are spread indirectly from one lizard mouth to another. Prey escaping an initial attack act as vectors in infecting new lizards. This model requires specific life history characteristics and ways to refute the model based on these characteristics are proposed and tested. Dragon life histories (some details of which are reported here) prove remarkably consistent with the model, especially that multiple, unrelated lizards feed communally on large carcasses and that escaping, wounded prey are ultimately fed on by other lizards. The identities and evolutionary histories of bacteria in the oral flora may yield the most useful additional insights for further testing the epidemic model and can now be obtained with new technologies.

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Worth a Thousand Words

Volcanic eruptions have been in the news quite a lot lately, what with Europe’s air traffic getting disrupted by the one in Iceland, and other smaller eruptions happening in other places as well. If you are not a professional volcanologist, it is likely that you have heard at least about the most famous volcanic eruption in history – the 79 AD eruption of Vesuvius that obliterated the city of Pompeii. I remember how fascinated I was with it when I was a kid and first read about it. What was most fascinating about that whole episode is how quickly people (and animals, like horses) died, even if they were miles away from the volcano itself. The death was so sudden, that most of the victims died in mid-movement and they were preserved in these eerie postures, a moment in time in the life of a city, frozen. You may have seen pictures (or if you are lucky, you visited Pompeii) like this:

One thing I remember from the time I read about this as a kid is the cause of death – suffocation with ash. And while some of the people died in poses that indicate suffering, others are captured in seemingly ordinary movements, as if they died of something much more swift than minutes of suffocating agony. And now, those suspicions I had have been resolved.

In last week’s PLoS ONE article Lethal Thermal Impact at Periphery of Pyroclastic Surges: Evidences at Pompeii, authors Giuseppe Mastrolorenzo, Pierpaolo Petrone, Lucia Pappalardo and Fabio Guarino of Napoli, Italy, performed a detailed analysis of volcanic rock and ash, as well as bones of human and equine victims of the eruption. And their conclusion is that people and animals died of high temperature – Vesuvius had six flashes of heat that suddenly heated up the air as high as 250 degrees Celsius (482 degrees Fahrenheit) at the distance of 10 kilometers from the mountain – hot enough to instantly kill.

Here is the Abstract and you can read the details of the paper itself as well:

Background

The evaluation of mortality of pyroclastic surges and flows (PDCs) produced by explosive eruptions is a major goal in risk assessment and mitigation, particularly in distal reaches of flows that are often heavily urbanized. Pompeii and the nearby archaeological sites preserve the most complete set of evidence of the 79 AD catastrophic eruption recording its effects on structures and people.

Methodology/Principal Findings

Here we investigate the causes of mortality in PDCs at Pompeii and surroundings on the bases of a multidisciplinary volcanological and bio-anthropological study. Field and laboratory study of the eruption products and victims merged with numerical simulations and experiments indicate that heat was the main cause of death of people, heretofore supposed to have died by ash suffocation. Our results show that exposure to at least 250°C hot surges at a distance of 10 kilometres from the vent was sufficient to cause instant death, even if people were sheltered within buildings. Despite the fact that impact force and exposure time to dusty gas declined toward PDCs periphery up to the survival conditions, lethal temperatures were maintained up to the PDCs extreme depositional limits.

Conclusions/Significance

This evidence indicates that the risk in flow marginal zones could be underestimated by simply assuming that very thin distal deposits, resulting from PDCs with poor total particle load, correspond to negligible effects. Therefore our findings are essential for hazard plans development and for actions aimed to risk mitigation at Vesuvius and other explosive volcanoes.

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Weekly PLoS ONE News and Blog Round-Up

In this week’s PLoS ONE media digest: one very old shoe, bluefin tuna spawning in the midst of oilspill, and much more….

First Direct Evidence of Chalcolithic Footwear from the Near Eastern Highlands by Pinhasi et al, recieved widespread coverage this week. It is impossible to collect all of the hundreds of links to all the articles and blog posts, so here is a more-or-less representative sample: Scientific American, National Geographic, Discovery News, Discover – 80beats, The Great Beyond, CNN, Prehistoric Archaeology Blog, everyONE blog, Reclusive Leftist, Huffington Post, Kris’s Archaeology Blog, Popular Fidelity, Ecouterre, StyleList, Heritage Key, Core77.com, Macleans, Independent, RadioFreeEurope, TODAYonline, Indian Express, Vanity Fair, BBC News, Associated Press, AssociatedPress (video), The Age, The Hindu, Mirror, Sify, Daily Mail, The Irish Times, Vancouver Sun, FOXNews.com, San Jose Mercury News, Times Online, National Post, The Press Association, Telegraph, AFP, Wikinews, Daily Contributor, Armenialiberty, Chromatography Today, Helium, People’s Daily Online, Irish Central, The Epoch Times, io9, Global Times, Styleite, New York Times, Examiner, AHN, Thaindian News, Thaindian News 2, AOL News, NewsLite, EurasiaNet, Tonic, Science News,
UPI, LA News Monitor, Metro, Irish Independent, HULIQ, Daily World Trends, UCLA Today, Cosmos, Toronto Star, Reuters India and Press TV.

Comparative Influence of Ocean Conditions on Yellowfin and Atlantic Bluefin Tuna Catch from Longlines in the Gulf of Mexico by Teo and Block was covered at Living the Scientific Life (Scientist, Interrupted), Inter Press Service, everyONE blog and A Blog Around The Clock.

Coevolution in Action: Disruptive Selection on Egg Colour in an Avian Brood Parasite and Its Host by Yang et al, was covered by Denim and Tweed.

Lowering β-Amyloid Levels Rescues Learning and Memory in a Down Syndrome Mouse Model by Netzer et al., was covered at Phased.

Marginal Eyespots on Butterfly Wings Deflect Bird Attacks Under Low Light Intensities with UV Wavelengths by Olofsson et al, was covered by Conservation Maven.

SUBTLEX-CH: Chinese Word and Character Frequencies Based on Film Subtitles by Cai and Brysbaert was covered at Greg Laden’s blog.

Follow-Up of Patients with Multidrug Resistant Tuberculosis Four Years after Standardized First-Line Drug Treatment by He et al., was covered by International Health Research.

The Power of Exercise: Buffering the Effect of Chronic Stress on Telomere Length by Puterman et al, was covered at UCSF news and Psych Central News.

Array-Based Whole-Genome Survey of Dog Saliva DNA Yields High Quality SNP Data by Yokoyama, Erdman and Hamilton, was covered by DNA Genotek’s Sample Collection Blog.

An Environment-Wide Association Study (EWAS) on Type 2 Diabetes Mellitus by Patel, Bhattacharya and Butte was covered at Periodic Tabloid.

Evaluating the Relative Environmental Impact of Countries by Bradshaw, Giam and Sodhi was covered by Aguanomics.

Glycemic Control Promotes Pancreatic Beta-Cell Regeneration in Streptozotocin-Induced Diabetic Mice by Grossman et al, was covered at Science Life Blog.

The Lagoon at Caroline/Millennium Atoll, Republic of Kiribati: Natural History of a Nearly Pristine Ecosystem by Barott et al, was noted at Science Today and LiveScience.

OAS1 Polymorphisms Are Associated with Susceptibility to West Nile Encephalitis in Horses by Rios et al was covered by Insciences Organisation and TheHorse.

First Person Experience of Body Transfer in Virtual Reality by Mel Slater, Bernhard Spanlang, Maria V. Sanchez-Vives and Olaf Blanke was discussed at Before It’s News.

Expanding HAART Treatment to All Currently Eligible Individuals under the 2008 IAS-USA Guidelines in British Columbia, Canada by Lima, Hogg and Montaner, was covered by PhysOrg.

Changing Patterns of Microhabitat Utilization by the Threespot Damselfish, Stegastes planifrons, on Caribbean Reefs by Precht et al. was covered by Practical Fishkeeping.

Same-Sex Gaze Attraction Influences Mate-Choice Copying in Humans by Yorzinski and Platt was covered at Evolved Primate.

Characteristics of Adults with Anxiety or Depression Treated at an Internet Clinic: Comparison with a National Survey and an Outpatient Clinic by Titov et al, was covered by Greg Laden.

Human’s Cognitive Ability to Assess Facial Cues from Photographs: A Study of Sexual Selection in the Bolivian Amazon by Undurraga et al was covered at PhysOrg.

Establishing the Proteome of Normal Human Cerebrospinal Fluid by Schutzer et al, was reported in Oneindia.

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