A Blog Around The Clock

Honest Lovers? Fallow Buck Groans Reveal Their Status And Size During The Rut:

It is known that the phonic structure of calls produced by males during the breeding season may signal quality-related characteristics in many different types of animals. Previous research on mammals has mainly focused on the relationship between the acoustic components of vocalizations and one aspect of male quality: body size.

Digitizing Archives From The 17th Century:

A researcher on a short trip to a foreign country, with little money, but a digital camera in hand has devised a novel approach to digitizing foreign archives that could speed up research.

Should Nurses Replace GPs As Frontline Providers Of Primary Care?:

Should nurses be the frontline providers of primary care, taking the place of general practitioners as the first point of patient contact? Two experts debate the issue on the British Medical Journal website.

Old Before Their Time? Aging Rate In Flies Twice As Fast In Wild Than In Laboratory:

Evolutionary studies of aging typically utilize small, short-lived animals (insects, worms, mice) under benign conditions – constant temperature and humidity, no parasites, superabundant food – in the laboratory.

Thinking People Eat Too Much: Intellectual Work Found To Induce Excessive Calorie Intake:

A Universite Laval research team has demonstrated that intellectual work induces a substantial increase in calorie intake. The details of this discovery, which could go some way to explaining the current obesity epidemic, are published in the most recent issue of Psychosomatic Medicine.

Children With TVs Or Computers In Their Room Sleep Less:

Middle school children who have a television or computer in their room sleep less during the school year, watch more TV, play more computer games and surf the net more than their peers who don’t – reveals joint research conducted by the University of Haifa and Jezreel Valley College.

Hallucinations In The Flash Of An Eye:

Ever seen or heard something that wasn’t there? For most of us such experiences – termed hallucinations – are a normal, fleeting, brain glitch; yet for a few they are persistent, distressing and associated with a range of psychiatric, neurological and eye conditions.

Yale Researchers Find ‘Junk DNA’ May Have Triggered Key Evolutionary Changes In Human Thumb And Foot:

Out of the 3 billion genetic letters that spell out the human genome, Yale scientists have found a handful that may have contributed to the evolutionary changes in human limbs that enabled us to manipulate tools and walk upright.

There are 9 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Sampling for Global Epidemic Models and the Topology of an International Airport Network:

Mathematical models that describe the global spread of infectious diseases such as influenza, severe acute respiratory syndrome (SARS), and tuberculosis (TB) often consider a sample of international airports as a network supporting disease spread. However, there is no consensus on how many cities should be selected or on how to select those cities. Using airport flight data that commercial airlines reported to the Official Airline Guide (OAG) in 2000, we have examined the network characteristics of network samples obtained under different selection rules. In addition, we have examined different size samples based on largest flight volume and largest metropolitan populations. We have shown that although the bias in network characteristics increases with the reduction of the sample size, a relatively small number of areas that includes the largest airports, the largest cities, the most-connected cities, and the most central cities is enough to describe the dynamics of the global spread of influenza. The analysis suggests that a relatively small number of cities (around 200 or 300 out of almost 3000) can capture enough network information to adequately describe the global spread of a disease such as influenza. Weak traffic flows between small airports can contribute to noise and mask other means of spread such as the ground transportation.

Can anyone send me the actual paper that is described in the first press release on this list, please?
What Is A Gene? Media Define the Concept In Many Different Ways:

Even scientists define ‘a gene’ in different ways, so it comes as little surprise that the media also have various ways of framing the concept of a gene, according to a new study. The study, Frame that gene, is based on the analysis of 300 articles in British and Norwegian newspapers: The Guardian, The Sun and The Daily Mail from the UK; and Aftenposten, Dagbladet, and VG from Norway.

Mom’s Mood, Baby’s Sleep: What’s The Connection?:

If there’s one thing that everyone knows about newborn babies, it’s that they don’t sleep through the night, and neither do their parents. But in fact, those first six months of life are crucial to developing the regular sleeping and waking patterns, known as circadian rhythms, that a child will need for a healthy future. Some children may start life with the sleep odds stacked against them, though, say University of Michigan sleep experts who study the issue. They will present data from their study next week at the European Sleep Research Society meeting in Glasgow, Scotland.

Computerized Whiteboards Improve Classroom Learning, Study Suggests:

The British government has invested more money in Interactive Whiteboards (IWBs) in its schools than any other government in the world. But is this huge investment worth it? Have the new data projection technologies allowed students to learn more effectively?

Designer Wine? Characterization Of Grapevine Transposons May Aid Development Of New Grape Varieties:

The grapevine (Vitis vinifera) is a widely cultivated crop that has been subjected to intensive breeding since the Neolithic period (from ~10,500 to ~6,000 years ago). The domestication of grapevine has undergone a selection for traits important for its cultivation and usage.

DNA Shows That Last Woolly Mammoths Had North American Roots:

In a surprising reversal of conventional wisdom, a DNA-based study has revealed that the last of the woolly mammoths–which lived between 40,000 and 4,000 years ago–had roots that were exclusively North American.

Biocontrol Insect Exacerbates Invasive Weed:

Biocontrol agents, such as insects, are often released outside of their native ranges to control invasive plants. But scientists in Montana have found that through complex community interactions among deer mice, native plants and seeds, the presence of an introduced fly may exacerbate the effects of the invasive plant it was meant to control. The authors report their results in the September issue of the journal Ecological Applications.

There are 10 new articles in PLoS ONE this week. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Targeted Destruction of Photosensitive Retinal Ganglion Cells with a Saporin Conjugate Alters the Effects of Light on Mouse Circadian Rhythms:

Non-image related responses to light, such as the synchronization of circadian rhythms to the day/night cycle, are mediated by classical rod/cone photoreceptors and by a small subset of retinal ganglion cells that are intrinsically photosensitive, expressing the photopigment, melanopsin. This raises the possibility that the melanopsin cells may be serving as a conduit for photic information detected by the rods and/or cones. To test this idea, we developed a specific immunotoxin consisting of an anti-melanopsin antibody conjugated to the ribosome-inactivating protein, saporin. Intravitreal injection of this immunotoxin results in targeted destruction of melanopsin cells. We find that the specific loss of these cells in the adult mouse retina alters the effects of light on circadian rhythms. In particular, the photosensitivity of the circadian system is significantly attenuated. A subset of animals becomes non-responsive to the light/dark cycle, a characteristic previously observed in mice lacking rods, cones, and functional melanopsin cells. Mice lacking melanopsin cells are also unable to show light induced negative masking, a phenomenon known to be mediated by such cells, but both visual cliff and light/dark preference responses are normal. These data suggest that cells containing melanopsin do indeed function as a conduit for rod and/or cone information for certain non-image forming visual responses. Furthermore, we have developed a technique to specifically ablate melanopsin cells in the fully developed adult retina. This approach can be applied to any species subject to the existence of appropriate anti-melanopsin antibodies.

Toward a Comprehensive Approach to the Collection and Analysis of Pica Substances, with Emphasis on Geophagic Materials:

Pica, the craving and subsequent consumption of non-food substances such as earth, charcoal, and raw starch, has been an enigma for more than 2000 years. Currently, there are little available data for testing major hypotheses about pica because of methodological limitations and lack of attention to the problem. In this paper we critically review procedures and guidelines for interviews and sample collection that are appropriate for a wide variety of pica substances. In addition, we outline methodologies for the physical, mineralogical, and chemical characterization of these substances, with particular focus on geophagic soils and clays. Many of these methods are standard procedures in anthropological, soil, or nutritional sciences, but have rarely or never been applied to the study of pica. Physical properties of geophagic materials including color, particle size distribution, consistency and dispersion/flocculation (coagulation) should be assessed by appropriate methods. Quantitative mineralogical analyses by X-ray diffraction should be made on bulk material as well as on separated clay fractions, and the various clay minerals should be characterized by a variety of supplementary tests. Concentrations of minerals should be determined using X-ray fluorescence for non-food substances and inductively coupled plasma-atomic emission spectroscopy for food-like substances. pH, salt content, cation exchange capacity, organic carbon content and labile forms of iron oxide should also be determined. Finally, analyses relating to biological interactions are recommended, including determination of the bioavailability of nutrients and other bioactive components from pica substances, as well as their detoxification capacities and parasitological profiles. This is the first review of appropriate methodologies for the study of human pica. The comprehensive and multi-disciplinary approach to the collection and analysis of pica substances detailed here is a necessary preliminary step to understanding the nutritional enigma of non-food consumption.

Cigarettes’ Power May Not Be In Nicotine Itself, New Study Suggests:

There may be a very good reason why coffee and cigarettes often seem to go hand in hand. A Kansas State University psychology professor’s research suggests that nicotine’s power may be in how it enhances other experiences. For a smoker who enjoys drinking coffee, the nicotine may make a cup of joe even better.

Participating In Religion May Make Adolescents From Certain Races More Depressed:

One of the few studies to look at the effects of religious participation on the mental health of minorities suggests that for some of them, religion may actually be contributing to adolescent depression. Previous research has shown that teens who are active in religious services are depressed less often because it provides these adolescents with social support and a sense of belonging. But new research has found that this does not hold true for all adolescents, particularly for minorities and some females.

Loss Of Sleep, Even For A Single Night, Increases Inflammation In The Body:

Loss of sleep, even for a few short hours during the night, can prompt one’s immune system to turn against healthy tissue and organs.

PET Scans Help Identify Mechanism Underlying Seasonal Mood Changes:

Brain scans taken at different times of year suggest that the actions of the serotonin transporter–involved in regulating the mood-altering neurotransmitter serotonin–vary by season, according to a new report. These fluctuations may potentially explain seasonal affective disorder and related mood changes.

Speed Of Growth Of Young Dogs And Development Of Common Skeletal Diseases Not A Simple Relationship:

Cand. med. vet. Cathrine Trangerud defended her thesis for the degree of Philosophiae Doctor at the Norwegian School of Veterinary Science on August 22, 2008, entitled “Growth patterns and metaphyseal irregularities in dogs: a study of 4 large breeds with emphasis on irregularities in the distal metaphysis of the radius and ulna in Newfoundland dogs”.

Molecular Evolution Is Echoed In Bat Ears:

Echolocation may have evolved more than once in bats, according to new research from the University of Bristol.

Oldest Gecko Fossil Ever Found, Entombed In Amber:

Scientists from Oregon State University and the Natural History Museum in London have announced the discovery of the oldest known fossil of a gecko, with body parts that are forever preserved in life-like form after 100 million years of being entombed in amber.

Black-footed Ferrets Sired By Dead Males Via Frozen Sperm:

Two black-footed ferrets at the Smithsonian’s National Zoo have each given birth to a kit that was sired by males who died in 1999 and 2000. These endangered ferrets–part of a multi-institutional breeding and reintroduction program–were artificially inseminated in May with frozen semen from the two deceased males, each giving birth to a kit on June 20 and 21 respectively.

Wolves Would Rather Eat Salmon:

Although most people imagine wolves chasing deer and other hoofed animals, new research suggests that, when they can, wolves actually prefer fishing to hunting. The study shows that when salmon is available, wolves will reduce deer hunting activity and instead focus on seafood.

Do 68 Molecules Hold The Key To Understanding Disease?:

Why is it that the origins of many serious diseases remain a mystery? In considering that question, a scientist at the University of California, San Diego School of Medicine has come up with a unified molecular view of the indivisible unit of life, the cell, which may provide an answer.

New Giant Clam Species Offers Window Into Human Past:

Researchers report the discovery of the first new living species of giant clam in two decades, according to a report to be published online on August 28th in Current Biology. While fossil evidence reveals that the new species, called Tridacna costata, once accounted for more than 80 percent of giant clams in the Red Sea, it now represents less than one percent of giant clams living there.

There are 11 new articles in PLoS ONE this week. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Flowering Time Diversification and Dispersal in Central Eurasian Wild Wheat Aegilops tauschii Coss.: Genealogical and Ecological Framework:

Timing of flowering is a reproductive trait that has significant impact on fitness in plants. In contrast to recent advances in understanding the molecular basis of floral transition, few empirical studies have addressed questions concerning population processes of flowering time diversification within species. We analyzed chloroplast DNA genealogical structure of flowering time variation in central Eurasian wild wheat Aegilops tauschii Coss. using 200 accessions that represent the entire species range. Flowering time measured as days from germination to flowering varied from 144.0 to 190.0 days (average 161.3 days) among accessions in a common garden/greenhouse experiment. Subsequent genealogical and statistical analyses showed that (1) there exist significant longitudinal and latitudinal clines in flowering time at the species level, (2) the early-flowering phenotype evolved in two intraspecific lineages, (3) in Asia, winter temperature was an environmental factor that affected the longitudinal clinal pattern of flowering time variation, and (4) in Transcaucasus-Middle East, some latitudinal factors affected the geographic pattern of flowering time variation. On the basis of palaeoclimatic, biogeographic, and genetic evidence, the northern part of current species’ range [which was within the temperate desert vegetation (TDV) zone at the Last Glacial Maximum] is hypothesized to have harbored species refugia. Postglacial southward dispersal from the TDV zone seems to have been driven by lineages that evolved short-flowering-time phenotypes through different genetic mechanisms in Transcaucasus-Middle East and Asia.

A Reversible Color Polyphenism in American Peppered Moth (Biston betularia cognataria) Caterpillars:

Insect body color polyphenisms enhance survival by producing crypsis in diverse backgrounds. While color polyphenisms are often indirectly induced by temperature, rearing density, or diet, insects can benefit from immediate crypsis if they evolve polyphenisms directly induced by exposure to the background color, hence immediately deriving protection from predation. Here, we examine such a directly induced color polyphenism in caterpillars of the geometrid peppered moth (Biston betularia). This larval color polyphenism is unrelated to the genetic polymorphism for melanic phenotypes in adult moths. B. betularia caterpillars are generalist feeders and develop body colors that closely match the brown or green twigs of their host plant. We expand on previous studies examining the proximal cues that stimulate color development. Under controlled rearing conditions, we manipulated diets and background reflectance, using both natural and artificial twigs, and show that visual experience has a much stronger effect than does diet in promoting precise color matching. Their induced body color was not a simple response to reflectance or light intensity but instead specifically matched the wavelength of light to which they were exposed. We also show that the potential to change color is retained until the final (sixth) larval instar. Given their broad host range, this directly induced color polyphenism likely provides the caterpillars with strong protection from bird predation.

Lack of Association between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study:

The presence of measles virus (MV) RNA in bowel tissue from children with autism spectrum disorders (ASD) and gastrointestinal (GI) disturbances was reported in 1998. Subsequent investigations found no associations between MV exposure and ASD but did not test for the presence of MV RNA in bowel or focus on children with ASD and GI disturbances. Failure to replicate the original study design may contribute to continued public concern with respect to the safety of the measles, mumps, and rubella (MMR) vaccine. The objective of this case-control study was to determine whether children with GI disturbances and autism are more likely than children with GI disturbances alone to have MV RNA and/or inflammation in bowel tissues and if autism and/or GI episode onset relate temporally to receipt of MMR. The sample was an age-matched group of US children undergoing clinically-indicated ileocolonoscopy. Ileal and cecal tissues from 25 children with autism and GI disturbances and 13 children with GI disturbances alone (controls) were evaluated by real-time reverse transcription (RT)-PCR for presence of MV RNA in three laboratories blinded to diagnosis, including one wherein the original findings suggesting a link between MV and ASD were reported. The temporal order of onset of GI episodes and autism relative to timing of MMR administration was examined. We found no differences between case and control groups in the presence of MV RNA in ileum and cecum. Results were consistent across the three laboratory sites. GI symptom and autism onset were unrelated to MMR timing. Eighty-eight percent of ASD cases had behavioral regression. This study provides strong evidence against association of autism with persistent MV RNA in the GI tract or MMR exposure. Autism with GI disturbances is associated with elevated rates of regression in language or other skills and may represent an endophenotype distinct from other ASD.

Brain Imaging Links Chronic Insomnia To Reversible Cognitive Deficits Without Changes In Behavior:

A neuroimaging study has found that cognitive processes related to verbal fluency are compromised in people with insomnia despite the absence of a behavioral deficit. These specific brain function alterations can be reversed, however, through non-pharmacological treatment with sleep therapy.

Periodic Limb Movement During Sleep Is Less Common In African-Americans; Associated With Insomnia:

A new study objectively determined the prevalence of periodic limb movements during sleep (PLMS) in a population-based sample, finding a lower prevalence of PLMS in African-Americans and a higher rate of insomnia complaints in people with PLMS.

More Daytime Sleeping Predicts Less Recovery During Rehabilitation For Older Adults:

A new study shows that daytime sleeping during a rehabilitation stay predicts less functional recovery for older adults, with effects lasting as long as three months.

Playing, And Even Watching, Sports Improves Brain Function:

Being an athlete or merely a fan improves language skills when it comes to discussing their sport because parts of the brain usually involved in playing sports are instead used to understand sport language, new research at the University of Chicago shows.

Infidelity Gene? Genetic Link To Relationship Difficulties Found:

Scientists at Karolinska Institutet have found a link between a specific gene and the way men bond to their partners. The results, which are presented in the scientific journal PNAS, can lead to a better understanding of such problems as autism and social phobia.

Teen Suicide Spike Was No Fluke:

A troubling new study raises new concerns about kids committing suicide in the U.S. After a one year spike in the number of suicides, doctors were hoping to see more normal numbers in the latest study, but they didn’t. The number of kids committing suicide in the U.S. remains higher than expected, and that has doctors and parents looking for answers.

Collective Traumas: Early Explanations Of 9/11 Linked To Long-term Adjustment:

According to new research led by John Updegraff, a Kent State University professor, individuals who are able to quickly make sense of collective traumas such as the 9/11 terrorist attacks cope better in the long run.

Zen Training Speeds The Mind’s Return After Distraction, Brain Scans Reveal:

Experienced Zen meditators can clear their minds of distractions more quickly than novices, according to a new brain imaging study.

Directing A Driver’s Gaze Results In Smoother Steering:

Typically, drivers gaze along a curve as they negotiate it, but they also look at other parts of the road, the dashboard, traffic signs and oncoming vehicles.

There are 12 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Low Frequency Groans Indicate Larger and More Dominant Fallow Deer (Dama dama) Males:

Models of honest advertisement predict that sexually selected calls should signal male quality. In most vertebrates, high quality males have larger body sizes that determine higher social status and in turn higher reproductive success. Previous research has emphasised the importance of vocal tract resonances or formant frequencies of calls as cues to body size in mammals. However, the role of the acoustic features of vocalisations as cues to other quality-related phenotypic characteristics of callers has rarely been investigated. We examined whether the acoustic structure of fallow deer groans provides reliable information on the quality of the caller, by exploring the relationships between male quality (body size, dominance rank, and mating success) and the frequency components of calls (fundamental frequency, formant frequencies, and formant dispersion). We found that body size was not related to the fundamental frequency of groans, whereas larger males produced groans with lower formant frequencies and lower formant dispersion. Groans of high-ranking males were characterised by lower minimum fundamental frequencies and to a lesser extent, by lower formant dispersions. Dominance rank was the factor most strongly related to mating success, with higher-ranking males having higher mating success. The minimum fundamental frequency and the minimum formant dispersion were indirectly related to male mating success (through dominance rank). Our study is the first to show that sexually selected vocalisations can signal social dominance in mammals other than primates, and reveals that independent acoustic components encode accurate information on different phenotypic aspects of male quality.

‘Thinking about Not-Thinking’: Neural Correlates of Conceptual Processing during Zen Meditation:

Recent neuroimaging studies have identified a set of brain regions that are metabolically active during wakeful rest and consistently deactivate in a variety the performance of demanding tasks. This “default network” has been functionally linked to the stream of thoughts occurring automatically in the absence of goal-directed activity and which constitutes an aspect of mental behavior specifically addressed by many meditative practices. Zen meditation, in particular, is traditionally associated with a mental state of full awareness but reduced conceptual content, to be attained via a disciplined regulation of attention and bodily posture. Using fMRI and a simplified meditative condition interspersed with a lexical decision task, we investigated the neural correlates of conceptual processing during meditation in regular Zen practitioners and matched control subjects. While behavioral performance did not differ between groups, Zen practitioners displayed a reduced duration of the neural response linked to conceptual processing in regions of the default network, suggesting that meditative training may foster the ability to control the automatic cascade of semantic associations triggered by a stimulus and, by extension, to voluntarily regulate the flow of spontaneous mentation.

Genome-Wide Analysis of the ‘Cut-and-Paste’ Transposons of Grapevine:

The grapevine is a widely cultivated crop and a high number of different varieties have been selected since its domestication in the Neolithic period. Although sexual crossing has been a major driver of grapevine evolution, its vegetative propagation enhanced the impact of somatic mutations and has been important for grapevine diversity. Transposable elements are known to be major contributors to genome variability and, in particular, to somatic mutations. Thus, transposable elements have probably played a major role in grapevine domestication and evolution. The recent publication of the complete grapevine genome opens the possibility for an in deep analysis of its transposon content. We present here a detailed analysis of the “cut-and-paste” class II transposons present in the genome of grapevine. We characterized 1160 potentially complete grapevine transposons as well as 2086 defective copies. We report on the structure of each element, their potentiality to encode a functional transposase, and the existence of matching ESTs that could suggest their transcription. Our results show that these elements have transduplicated and amplified cellular sequences and some of them have been domesticated and probably fulfill cellular functions. In addition, we provide evidences that the mobility of these elements has contributed to the genomic variability of this species.

Peripheral and Central Determinants of a Nociceptive Reaction: An Approach to Psychophysics in the Rat:

The quantitative end-point for many behavioral tests of nociception is the reaction time, i.e. the time lapse between the beginning of the application of a stimulus, e.g. heat, and the evoked response. Since it is technically impossible to heat the skin instantaneously by conventional means, the question of the significance of the reaction time to radiant heat remains open. We developed a theoretical framework, a related experimental paradigm and a model to analyze in psychophysical terms the “tail-flick” responses of rats to random variations of noxious radiant heat. A CO2 laser was used to avoid the drawbacks associated with standard methods of thermal stimulation. Heating of the skin was recorded with an infrared camera and was stopped by the reaction of the animal. For the first time, we define and determine two key descriptors of the behavioral response, namely the behavioral threshold (Tβ) and the behavioral latency (Lβ). By employing more than one site of stimulation, the paradigm allows determination of the conduction velocity of the peripheral fibers that trigger the response (V) and an estimation of the latency (Ld) of the central decision-making process. Ld (~130 ms) is unaffected by ambient or skin temperature changes that affect the behavioral threshold (~42.2-44.9°C in the 20-30°C range), behavioral latency (<500 ms), and the conduction velocity of the peripheral fibers that trigger the response (~0.35-0.76 m/s in the 20-30°C range). We propose a simple model that is verified experimentally and that computes the variations in the so-called "tail-flick latency" (TFL) caused by changes in either the power of the radiant heat source, the initial temperature of the skin, or the site of stimulation along the tail. This approach enables the behavioral determinations of latent psychophysical (Tβ, Lβ, Ld) and neurophysiological (V) variables that have been previously inaccessible with conventional methods. Such an approach satisfies the repeated requests for improving nociceptive tests and offers a potentially heuristic progress for studying nociceptive behavior on more firm physiological and psychophysical grounds. The validity of using a reaction time of a behavioral response to an increasing heat stimulus as a "pain index" is challenged. This is illustrated by the predicted temperature-dependent variations of the behavioral TFL elicited by spontaneous variations of the temperature of the tail for thermoregulation.