A Blog Around The Clock

How Poisonous Mushrooms Cook Up Toxins:

Alpha-amanitin is the poison of the death cap mushroom, Amanita phalloides. The Michigan State University plant biology research associate was looking for a big gene that makes a big enzyme that produces alpha-amanitin, since that’s how other fungi produce similar compounds. But after years of defeat, she and her team called in the big guns — new technology that sequences DNA about as fast as a death cap mushroom can kill. The results: The discovery of remarkably small genes that produce the toxin — a unique pathway previously unknown in fungi.

Brain Matures A Few Years Late In ADHD, But Follows Normal Pattern:

In youth with attention deficit hyperactivity disorder (ADHD), the brain matures in a normal pattern but is delayed three years in some regions, on average, compared to youth without the disorder, an imaging study by researchers at the National Institutes of Health’s (NIH) National Institute of Mental Health (NIMH) has revealed. The delay in ADHD was most prominent in regions at the front of the brain’s outer mantle (cortex), important for the ability to control thinking, attention and planning. Otherwise, both groups showed a similar back-to-front wave of brain maturation with different areas peaking in thickness at different times.

Tool-wielding Chimps Provide A Glimpse Of Early Human Behavior:

Chimpanzees inhabiting a harsh savanna environment and using bark and stick tools to exploit an underground food resource are giving scientists new insights to the behaviors of the earliest hominids who, millions of years ago, left the African forests to range the same kinds of environments and possibly utilize the same foods.

Tiny Fish Can Yield Big Clues To Delaware River Health:

Where have all the bridle shiner gone? That’s the mystery The Academy of Natural Sciences’ fish scientists are trying to answer, and the outcome will shed light on the environmental health of the Upper Delaware River.

Changing Environment Organizes Genetic Structure:

What is the fundamental creative force behind life on Earth? It’s a question that has vexed mankind for millennia, and thanks to theory and almost a year’s worth of number-crunching on a supercomputer, Rice University physicist and bioengineer Michael Deem thinks he has the answer: A changing environment may organize the structure of genetic information itself.

ECGC In Green Tea Is Powerful Medicine Against Severe Sepsis, Lab Study Suggests:

A major component of green tea could prove the perfect elixir for severe sepsis, an abnormal immune system response to a bacterial infection. In a new laboratory study, Haichao Wang, PhD, of The Feinstein Institute for Medical Research, and his colleagues have been studying the therapeutic powers of dozens of Chinese herbal compounds in reversing a fatal immune response that kills 225,000 Americans every year. They found that an ingredient in green tea rescued mice from lethal sepsis — and the findings could pave the way to clinical trials in patients.

How Global Is The Global Biodiversity Information Facility?:

Biologists and computer scientists have appealed for more information on the world’s biodiversity to be stored digitally so it may better be used to understand the impact of climate change on the Earth’s flora and fauna.

‘Time-sharing’ Tropical Birds Key To Evolutionary Mystery:

Whereas most birds are sole proprietors of their nests, some tropical species “time share” together – a discovery that helps clear up a 150-year-old evolutionary mystery, says Biology professor Vicki Friesen.

There are 27 brand-new articles, just uploaded on PLoS ONE. Here are a couple of titles that drew my immediate attention:
Maternal Enrichment during Pregnancy Accelerates Retinal Development of the Fetus:

Although much is known about the harmful effects parental stress has on offspring, little is understood about how enriching a mother’s environment affects fetal development. In this paper, the authors experiment on developing rat embryos and find that an enriched environment speeds up the development of the nervous system. The results suggest that development of the visual system is sensitive to environmental stimulation during prenatal life.

Prior Exposure to Uninfected Mosquitoes Enhances Mortality in Naturally-Transmitted West Nile Virus Infection:

West Nile Virus has the potential to cause serious disease in humans; the virus is spread by infected mosquitoes and typically infection either results in no symptoms or in mild feverish symptoms. In this study, Higgs and colleagues found that mice that had already been exposed to the saliva from uninfected mosquitoes were subsequently more likely to die upon being infected with West Nile Virus. These findings suggest that prior exposure to mosquito saliva could potentially result in a worse outcome from West Nile Virus infection.

Gene Expression in Human Hippocampus from Cocaine Abusers Identifies Genes which Regulate Extracellular Matrix Remodeling:

People who have abused drugs in the past find it hard to avoid relapse because they remember the euphoria linked to previous drug use. In order to see if past drug abuse is associated with molecular changes in the brain, the researchers here carried out microarray analysis of samples of the hippocampus from individuals addicted to cocaine, and from control individuals. The microarray data identifies a number of genes which are up- or down-regulated in response to cocaine exposure.

Incidence and Tracking of Escherichia coli O157:H7 in a Major Produce Production Region in California:

Fresh vegetables have become associated with outbreaks caused by Escherichia coli O157:H7 (EcO157). Between 1995-2006, 22 produce outbreaks were documented in the United States, with nearly half traced to lettuce or spinach grown in California. Outbreaks between 2002 and 2006 induced investigations of possible sources of pre-harvest contamination on implicated farms in the Salinas and San Juan valleys of California, and a survey of the Salinas watershed. EcO157 was isolated at least once from 15 of 22 different watershed sites over a 19 month period. The incidence of EcO157 increased significantly when heavy rain caused an increased flow rate in the rivers. Approximately 1000 EcO157 isolates obtained from cultures of>100 individual samples were typed using Multi-Locus Variable-number-tandem-repeat Analysis (MLVA) to assist in identifying potential fate and transport of EcO157 in this region. A subset of these environmental isolates were typed by Pulse Field Gel Electrophoresis (PFGE) in order to make comparisons with human clinical isolates associated with outbreak and sporadic illness. Recurrence of identical and closely related EcO157 strains from specific locations in the Salinas and San Juan valleys suggests that transport of the pathogen is usually restricted. In a preliminary study, EcO157 was detected in water at multiple locations in a low-flow creek only within 135 meters of a point source. However, possible transport up to 32 km was detected during periods of higher water flow associated with flooding. During the 2006 baby spinach outbreak investigation, transport was also detected where water was unlikely to be involved. These results indicate that contamination of the environment is a dynamic process involving multiple sources and methods of transport. Intensive studies of the sources, incidence, fate and transport of EcO157 near produce production are required to determine the mechanisms of pre-harvest contamination and potential risks for human illness.

Different Neurophysiological Mechanisms Underlying Word and Rule Extraction from Speech:

The initial process of identifying words from spoken language and the detection of more subtle regularities underlying their structure are mandatory processes for language acquisition. Little is known about the cognitive mechanisms that allow us to extract these two types of information and their specific time-course of acquisition following initial contact with a new language. We report time-related electrophysiological changes that occurred while participants learned an artificial language. These changes strongly correlated with the discovery of the structural rules embedded in the words. These changes were clearly different from those related to word learning and occurred during the first minutes of exposition. There is a functional distinction in the nature of the electrophysiological signals during acquisition: an increase in negativity (N400) in the central electrodes is related to word-learning and development of a frontal positivity (P2) is related to rule-learning. In addition, the results of an online implicit and a post-learning test indicate that, once the rules of the language have been acquired, new words following the rule are processed as words of the language. By contrast, new words violating the rule induce syntax-related electrophysiological responses when inserted online in the stream (an early frontal negativity followed by a late posterior positivity) and clear lexical effects when presented in isolation (N400 modulation). The present study provides direct evidence suggesting that the mechanisms to extract words and structural dependencies from continuous speech are functionally segregated. When these mechanisms are engaged, the electrophysiological marker associated with rule-learning appears very quickly, during the earliest phases of exposition to a new language.

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As always on Monday nights, there are new articles published in PLoS Biology and PLoS Medicine. My picks:
Professional Uncertainty and Disempowerment Responding to Ethnic Diversity in Health Care: A Qualitative Study

In a qualitative study published this week in PLoS Medicine, Joe Kai and colleagues have identified opportunities to empower health professionals to respond more effectively to challenges in their work with patients from diverse ethnic communities. A related perspective showcases the challenges that physicians face in providing culturally appropriate care.

Omnidirectional Sensory and Motor Volumes in Electric Fish:

Most animals, including humans, have sensory and motor capabilities that are biased in the forward direction. The black ghost knifefish, a nocturnal, weakly electric fish from the Amazon, is an interesting exception to this general rule. We demonstrate that these fish have sensing and motor capabilities that are omnidirectional. By combining video analysis of prey capture trajectories with computational modeling of the fish’s electrosensory capabilities, we were able to quantify and compare the 3-D volumes for sensation and movement. We found that the volume in which prey are detected is similar in size to the volume needed by the fish to stop. We suggest that this coupling may arise from constraints that the animal faces when using self-generated energy to probe its environment. This is similar to the way in which the angular coverage and range of an automobile’s headlights are designed to match certain motion characteristics of the vehicle, such as its typical cruising speed, turning angle, and stopping distance. We suggest that the degree of overlap between sensory and movement volumes can provide insight into the types of control strategies that are best suited for guiding behavior.

Also read the related synopsis. Interestingly, electroreception is the only sensory modality studied so far which does not exhibit centrifugal control, i.e., there is no “tuning” by the central nervous system – it is always tuned the same. In other senses (including some weird ones, e.g., magnetoreception), the brain modulates the sensitivity of the sensory organ. In all those cases, one of those modulations is by the circadian clock. Thus, all the senses except electroreception are more or less sensitive depending on the time of day. I wonder about the other active senses, i.e., senses in which animal emits something into the environment and then senses how the environment responds to it (e.g., sonar in dolphins, ultrasonic emitions of bats, etc.) as I am not sure those were studied.

How Well Do Dogs See At Night?:

A lot better than we do, says Paul Miller, clinical professor of comparative ophthalmology at University of Wisconsin-Madison.

Why Quitting Smoking Is So Difficult:

New findings clarify the brain mechanisms that explain many aspects of dependency on nicotine, the addictive substance in tobacco. Among them: Individual differences in brain chemistry can have a profound effect on a person’s susceptibility to addiction, and smoking may predispose adolescents to mental disorders in adolescence and adulthood. In addition, researchers have identified a potential neural network that regulates the body’s craving response and have demonstrated how smoking may affect decision-making.

For Migrating Sparrows, Kids Have A Compass, But Adults Have The Map:

Even bird brains can get to know an entire continent — but it takes them a year of migration to do so, suggests a Princeton research team.

One In Five Young Britons Has Sex With Someone New While Abroad:

Around one in five young Britons has sex with a new partner while overseas, finds research published ahead of print in the journal Sexually Transmitted Infections.

How The Brain Sends Eyeballs Bouncing:

All vision, including reading this sentence, depends on a constant series of infinitesimal jumps by the eyeball that centers the retina on target objects–words or phrases in the case of reading. Such jumps, or saccades, are critical to vision because only the small central region of the retina, called the fovea, produces the clear image necessary for perception. Such saccades take place several times a second and are generated within a brain region known as the frontal eye field (FEF).

Why Teens Are Such Impulsive Risk-takers:

Teenagers and adults often don’t see eye to eye, and new brain research is now shedding light on some of the reasons why. Although adolescence is often characterized by increased independence and a desire for knowledge and exploration, it also is a time when brain changes can result in high-risk behaviors, addiction vulnerability, and mental illness, as different parts of the brain mature at different rates.

When To Have A Child? A New Approach To The Decision:

Women seeking to balance career, social life and family life in making the decision on when to have a child may benefit from applying formal decision-making science to this complex emotional choice.

Bug-Zapper: A Dose Of Radiation May Help Knock Out Malaria:

How are physicists helping an effort to eradicate malaria, the mosquito-borne disease that kills more than one million people every year” Researchers at the National Institute of Standards and Technology (NIST) used their expertise in radiation science to help a young company create weakened, harmless versions of the malaria-causing parasite. These parasites, in turn, are being used to create a new type of vaccine that shows promise of being more effective than current malaria vaccines.

Why Dinosaurs Had ‘Fowl’ Breath:

Scientists have discovered how dinosaurs used to breathe in what provides clues to how they evolved and how they might have lived.

Sexist Humor No Laughing Matter, Psychologist Says:

A research project led by a Western Carolina University psychology professor indicates that jokes about blondes and women drivers are not just harmless fun and games; instead, exposure to sexist humor can lead to toleration of hostile feelings and discrimination against women.

Recreational Cocaine Use May Impair Inhibitory Control:

The recreational use of cocaine has rapidly increased in many European countries over the past few years. One cause of this is the fall in the price of the drug on the street from 100 Euros for one gram (about 5 lines) in 2000 to 50 Euros in the Netherlands today. One line of cocaine is, thus, now as cheap as a tablet of ecstasy. This means cocaine is no longer considered an “elite” drug but is affordable for all, especially for recreational use. It is therefore likely that the recreational use of cocaine will become a public health issue in the next few years, which is already the case for the recreational use of ecstasy.

To Fight Disease, Animals — Like Plants — Can Tolerate Parasites:

Animals, like plants, can build tolerance to infections at a genetic level, and these findings could provide a better understanding of the epidemiology and evolution of infectious disease, according to evolutionary biologists.

Lack Of Critical Lubricant Causes Wear In Animal Joints:

Mice that don’t produce lubricin, a thin film of protein found in the cartilage of joints, showed early wear and higher friction in their joints, a new study led by Brown University researchers shows.

Evolution: When Are Genes ‘Adventurous’ And When Are They Conservative?:

Taking a chance on an experiment – this is one of the impulses that drive evolution. Living cells are, from this angle, great subjects for experimentation: Changes in one molecule can have all sorts of interesting consequences for many other molecules in the cell. Such experiments on genes and proteins have led the cell, and indeed all life, on a long and fascinating evolutionary journey.

As always on Tuesdays late in the evening, there is a bunch of new papers published in PLoS ONE and here are my personal favourites of the week:
Oxytocin Increases Generosity in Humans:

Human beings routinely help strangers at costs to themselves. Sometimes the help offered is generous–offering more than the other expects. The proximate mechanisms supporting generosity are not well-understood, but several lines of research suggest a role for empathy. In this study, participants were infused with 40 IU oxytocin (OT) or placebo and engaged in a blinded, one-shot decision on how to split a sum of money with a stranger that could be rejected. Those on OT were 80% more generous than those given a placebo. OT had no effect on a unilateral monetary transfer task dissociating generosity from altruism. OT and altruism together predicted almost half the interpersonal variation in generosity. Notably, OT had twofold larger impact on generosity compared to altruism. This indicates that generosity is associated with both altruism as well as an emotional identification with another person.

Impaired Inhibitory Control in Recreational Cocaine Users:

Chronic use of cocaine is associated with impairment in response inhibition but it is an open question whether and to which degree findings from chronic users generalize to the upcoming type of recreational users. This study compared the ability to inhibit and execute behavioral responses in adult recreational users and in a cocaine-free-matched sample controlled for age, race, gender distribution, level of intelligence, and alcohol consumption. Response inhibition and response execution were measured by a stop-signal paradigm. Results show that users and non users are comparable in terms of response execution but users need significantly more time to inhibit responses to stop-signals than non users. Interestingly, the magnitude of the inhibitory deficit was positively correlated with the individuals lifetime cocaine exposure suggesting that the magnitude of the impairment is proportional to the degree of cocaine consumed.

Processing of Abstract Rule Violations in Audition:

The ability to encode rules and to detect rule-violating events outside the focus of attention is vital for adaptive behavior. Our brain recordings reveal that violations of abstract auditory rules are processed even when the sounds are unattended. When subjects performed a task related to the sounds but not to the rule, rule violations impaired task performance and activated a network involving supratemporal, parietal and frontal areas although none of the subjects acquired explicit knowledge of the rule or became aware of rule violations. When subjects tried to behaviorally detect rule violations, the brain’s automatic violation detection facilitated intentional detection. This shows the brain’s capacity for abstraction – an important cognitive function necessary to model the world. Our study provides the first evidence for the task-independence (i.e. automaticity) of this ability to encode abstract rules and for its immediate consequences for subsequent mental processes.

DNA Barcoding in the Cycadales: Testing the Potential of Proposed Barcoding Markers for Species Identification of Cycads:

The use of DNA barcoding to describe species that lack diagnostic features is becoming increasingly important for animal and plant conservation. In this paper, Specht and colleagues tested various genomic regions from a specific group of plants, the Cycadales, to see how effective these might be in providing unique species identifiers. The results enabled the researchers to suggest a workflow for producing and testing DNA barcoding data, which is an essential requirement to the establishment of a universal DNA barcode for plants.

A Major Ingredient of Green Tea Rescues Mice from Lethal Sepsis Partly by Inhibiting HMGB1:

The pathogenesis of sepsis is mediated in part by bacterial endotoxin, which stimulates macrophages/monocytes to sequentially release early (e.g., TNF, IL-1, and IFN-γ) and late (e.g., HMGB1) pro-inflammatory cytokines. Our recent discovery of HMGB1 as a late mediator of lethal sepsis has prompted investigation for development of new experimental therapeutics. We previously reported that green tea brewed from the leaves of the plant Camellia sinensis is effective in inhibiting endotoxin-induced HMGB1 release. Here we demonstrate that its major component, (-)-epigallocatechin-3-gallate (EGCG), but not catechin or ethyl gallate, dose-dependently abrogated HMGB1 release in macrophage/monocyte cultures, even when given 2-6 hours post LPS stimulation. Intraperitoneal administration of EGCG protected mice against lethal endotoxemia, and rescued mice from lethal sepsis even when the first dose was given 24 hours after cecal ligation and puncture. The therapeutic effects were partly attributable to: 1) attenuation of systemic accumulation of proinflammatory mediator (e.g., HMGB1) and surrogate marker (e.g., IL-6 and KC) of lethal sepsis; and 2) suppression of HMGB1-mediated inflammatory responses by preventing clustering of exogenous HMGB1 on macrophage cell surface. Taken together, these data suggest a novel mechanism by which the major green tea component, EGCG, protects against lethal endotoxemia and sepsis.

The Biomechanics of Amnion Rupture: An X-Ray Diffraction Study:

Pre-term birth is the leading cause of perinatal and neonatal mortality, 40% of which are attributed to the pre-term premature rupture of amnion. Rupture of amnion is thought to be associated with a corresponding decrease in the extracellular collagen content and/or increase in collagenase activity. However, there is very little information concerning the detailed organisation of fibrillar collagen in amnion and how this might influence rupture. Here we identify a loss of lattice like arrangement in collagen organisation from areas near to the rupture site, and present a 9% increase in fibril spacing and a 50% decrease in fibrillar organisation using quantitative measurements gained by transmission electron microscopy and the novel application of synchrotron X-ray diffraction. These data provide an accurate insight into the biomechanical process of amnion rupture and highlight X-ray diffraction as a new and powerful tool in our understanding of this process.

Unexpected High Losses of Anopheles gambiae Larvae Due to Rainfall:

Immature stages of the malaria mosquito Anopheles gambiae experience high mortality, but its cause is poorly understood. Here we study the impact of rainfall, one of the abiotic factors to which the immatures are frequently exposed, on their mortality. We show that rainfall significantly affected larval mosquitoes by flushing them out of their aquatic habitat and killing them. Outdoor experiments under natural conditions in Kenya revealed that the additional nightly loss of larvae caused by rainfall was on average 17.5% for the youngest (L1) larvae and 4.8% for the oldest (L4) larvae; an additional 10.5% (increase from 0.9 to 11.4%) of the L1 larvae and 3.3% (from 0.1 to 3.4%) of the L4 larvae were flushed away and larval mortality increased by 6.9% (from 4.6 to 11.5%) and 1.5% (from 4.1 to 5.6%) for L1 and L4 larvae, respectively, compared to nights without rain. On rainy nights, 1.3% and 0.7% of L1 and L4 larvae, respectively, were lost due to ejection from the breeding site. This study demonstrates that immature populations of malaria mosquitoes suffer high losses during rainfall events. As these populations are likely to experience several rain showers during their lifespan, rainfall will have a profound effect on the productivity of mosquito breeding sites and, as a result, on the transmission of malaria. These findings are discussed in the light of malaria risk and changing rainfall patterns in response to climate change.

Austro-Asiatic Tribes of Northeast India Provide Hitherto Missing Genetic Link between South and Southeast Asia:

Northeast India, the only region which currently forms a land bridge between the Indian subcontinent and Southeast Asia, has been proposed as an important corridor for the initial peopling of East Asia. Given that the Austro-Asiatic linguistic family is considered to be the oldest and spoken by certain tribes in India, Northeast India and entire Southeast Asia, we expect that populations of this family from Northeast India should provide the signatures of genetic link between Indian and Southeast Asian populations. In order to test this hypothesis, we analyzed mtDNA and Y-Chromosome SNP and STR data of the eight groups of the Austro-Asiatic Khasi from Northeast India and the neighboring Garo and compared with that of other relevant Asian populations. The results suggest that the Austro-Asiatic Khasi tribes of Northeast India represent a genetic continuity between the populations of South and Southeast Asia, thereby advocating that northeast India could have been a major corridor for the movement of populations from India to East/Southeast Asia.

Population Response to Habitat Fragmentation in a Stream-Dwelling Brook Trout Population:

Fragmentation can strongly influence population persistence and expression of life-history strategies in spatially-structured populations. In this study, we directly estimated size-specific dispersal, growth, and survival of stream-dwelling brook trout in a stream network with connected and naturally-isolated tributaries. We used multiple-generation, individual-based data to develop and parameterize a size-class and location-based population projection model, allowing us to test effects of fragmentation on population dynamics at local (i.e., subpopulation) and system-wide (i.e., metapopulation) scales, and to identify demographic rates which influence the persistence of isolated and fragmented populations. In the naturally-isolated tributary, persistence was associated with higher early juvenile survival (~45% greater), shorter generation time (one-half) and strong selection against large body size compared to the open system, resulting in a stage-distribution skewed towards younger, smaller fish. Simulating barriers to upstream migration into two currently-connected tributary populations caused rapid (2-6 generations) local extinction. These local extinctions in turn increased the likelihood of system-wide extinction, as tributaries could no longer function as population sources. Extinction could be prevented in the open system if sufficient immigrants from downstream areas were available, but the influx of individuals necessary to counteract fragmentation effects was high (7-46% of the total population annually). In the absence of sufficient immigration, a demographic change (higher early survival characteristic of the isolated tributary) was also sufficient to rescue the population from fragmentation, suggesting that the observed differences in size distributions between the naturally-isolated and open system may reflect an evolutionary response to isolation. Combined with strong genetic divergence between the isolated tributary and open system, these results suggest that local adaptation can ‘rescue’ isolated populations, particularly in one-dimensional stream networks where both natural and anthropogenically-mediated isolation is common. However, whether rescue will occur before extinction depends critically on the race between adaptation and reduced survival in response to fragmentation.

Randomised, Controlled, Assessor Blind Trial Comparing 4% Dimeticone Lotion with 0.5% Malathion Liquid for Head Louse Infestation:

Malathion 0.5% has been the most prescribed pediculicide in the United Kingdom for around 10 years, and is widely used in Europe and North America. Anecdotal reports suggest malathion treatments are less effective than formerly, but this has not been confirmed clinically. This study was designed to determine whether malathion is still effective and if 4% dimeticone lotion is a more effective treatment for head louse infestation. We designed this study as an assessor blinded, randomised, controlled, parallel group trial involving 58 children and 15 adults with active head louse infestation. Each participant received two applications 7 days apart of either 4% dimeticone lotion, applied for 8 hours or overnight, or 0.5% malathion liquid applied for 12 hours or overnight. All treatment and check-up visits were conducted in participants’ homes. Cure of infestation was defined as no evidence of head lice after the second treatment. Some people were found free from lice but later reinfested. Worst case, intention to treat, analysis found dimeticone was significantly more effective than malathion, with 30/43 (69.8%) participants cured using dimeticone compared with 10/30 (33.3%) using malathion (p<0.01, difference 36.4%, 95% confidence interval 14.7% to 58.2%). Per protocol analysis showed cure rates of 30/39 (76.9%) and 10/29 (34.5%) respectively. Irritant reactions were observed in only two participants, both treated with malathion. We concluded that, although malathion liquid is still effective for some people, dimeticone lotion offers a significantly more effective alternative treatment for most people.

Thermal Disruption of Mushroom Body Development and Odor Learning in Drosophila:

Environmental stress (nutritive, chemical, electromagnetic and thermal) has been shown to disrupt central nervous system (CNS) development in every model system studied to date. However, empirical linkages between stress, specific targets in the brain, and consequences for behavior have rarely been established. The present study experimentally demonstrates one such linkage by examining the effects of ecologically-relevant thermal stress on development of the Drosophila melanogaster mushroom body (MB), a conserved sensory integration and associative center in the insect brain. We show that a daily hyperthermic episode throughout larval and pupal development (1) severely disrupts MB anatomy by reducing intrinsic Kenyon cell (KC) neuron numbers but has little effect on other brain structures or general anatomy, and (2) greatly impairs associative odor learning in adults, despite having little effect on memory or sensory acuity. Hence, heat stress of ecologically relevant duration and intensity can impair brain development and learning potential.

How Global Is the Global Biodiversity Information Facility?:

There is a concerted global effort to digitize biodiversity occurrence data from herbarium and museum collections that together offer an unparalleled archive of life on Earth over the past few centuries. The Global Biodiversity Information Facility provides the largest single gateway to these data. Since 2004 it has provided a single point of access to specimen data from databases of biological surveys and collections. Biologists now have rapid access to more than 120 million observations, for use in many biological analyses. We investigate the quality and coverage of data digitally available, from the perspective of a biologist seeking distribution data for spatial analysis on a global scale. We present an example of automatic verification of geographic data using distributions from the International Legume Database and Information Service to test empirically, issues of geographic coverage and accuracy. There are over 1/2 million records covering 31% of all Legume species, and 84% of these records pass geographic validation. These data are not yet a global biodiversity resource for all species, or all countries. A user will encounter many biases and gaps in these data which should be understood before data are used or analyzed. The data are notably deficient in many of the world’s biodiversity hotspots. The deficiencies in data coverage can be resolved by an increased application of resources to digitize and publish data throughout these most diverse regions. But in the push to provide ever more data online, we should not forget that consistent data quality is of paramount importance if the data are to be useful in capturing a meaningful picture of life on Earth.

As always, go and read, rate, comment, annotate and trackback your blog posts….

Circadian Disorders And Adjusting To The Night Shift: Guide For Professionals:

Practice parameters are a guide to the appropriate assessment and treatment of circadian rhythm sleep disorders (CRSDs). The standards will have a positive impact on professional behavior, patient outcomes and possibly health care costs.

Sleep-related Breathing Disorder Linked To Increased Heart Rate Variability:

A sleep-related breathing disorder, common in heart failure, increases one’s heart rate variability. Further, central sleep apnea (CSA) and obstructive sleep apnea (OSA) produce different patterns of heart rate variability, which are likely to reflect the different pathophysiological mechanisms involved, according to a new study.

For Migrating Sparrows, Kids Have A Compass, But Adults Have The Map:

Even bird brains can get to know an entire continent — but it takes them a year of migration to do so, suggests a Princeton research team.

Smell You Later: Scientists Reveal How Mice Recognize Each Other:

Scientists at the University of Liverpool have discovered that mice rely on a special set of proteins to recognise each other. Previous study assumed that another set of genes that influence smell in vertebrates might be used by animals that identify each other through scent. The team found, however, that mice use a highly specialised set of proteins in their urine to recognise different individuals, suggesting that this may also be true of other animals.

New Species Of Peccary –pig-like Animal — Discovered In Amazon Region:

Dutch biologist Marc van Roosmalen has discovered a new species of peccary, a member of the pig family, in the basin of the Rio Aripuanã in the south-eastern Amazon region. The divergence time from the already known peccary species (the time which has passed since the evolutionary division) has been set at one to 1.2 million years.

Mice Influenced By Traumatic ‘Childhood’ Experiences:

How does the experience of traumatic stress in childhood affect one’s life in subsequent years? Leo Enthoven, a PhD student at the Leiden / Amsterdam Center for Drug Research (LACDR) and Leiden University Medical Center (LUMC) studied this subject in a laboratory animal model. He has achieved some remarkable results with mice, but cannot yet say anything about humans.

Tiger Numbers Could Be Doubled In South Asia:

Researchers at the Wildlife Conservation Society and other institutions declare that improvements in management of existing protected areas in South Asia could double the number of tigers currently existing in the region.

All Male or All Female Litter? Sex-ratio Meiotic Drive System Identified In Fruit Flies:

If you met a person who had 10 children, all of whom were girls, you would probably find this surprising. Yet this kind of distorted sex ratio does occur in groups as diverse as mammals, insects, and plants, where some parents consistently produce litters in which the sex ratio is dramatically skewed.

Rest For The Racehorse After Exercise:

Equine muscle glycogen stores require sufficient time for post-exercise repletion. Repletion cannot be hastened in any way other than rest.

Earliest Birds Acted More Like Turkeys Than Common Cuckoos:

The earliest birds acted more like turkeys than common cuckoos, according to a new report. By comparing the claw curvatures of ancient and modern birds, the researchers provide new evidence that the evolutionary ancestors of birds primarily made their livings on the ground rather than in trees.