There are 27 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. You can now also easily place articles on various social services (CiteULike, Mendeley, Connotea, Stumbleupon, Facebook and Digg) with just one click. Here are my own picks for the week - you go and look for your own favourites:
Basal sauropodomorphs, or 'prosauropods,' are a globally widespread paraphyletic assemblage of terrestrial herbivorous dinosaurs from the Late Triassic and Early Jurassic. In contrast to several other landmasses, the North American record of sauropodomorphs during this time interval remains sparse, limited to Early Jurassic occurrences of a single well-known taxon from eastern North America and several fragmentary specimens from western North America. On the basis of a partial skeleton, we describe here a new basal sauropodomorph dinosaur from the Lower Jurassic Navajo Sandstone of southern Utah, Seitaad ruessi gen. et sp. nov. The partially articulated skeleton of Seitaad was likely buried post-mortem in the base of a collapsed dune foreset. The new taxon is characterized by a plate-like medial process of the scapula, a prominent proximal expansion of the deltopectoral crest of the humerus, a strongly inclined distal articular surface of the radius, and a proximally and laterally hypertrophied proximal metacarpal I. Phylogenetic analysis recovers Seitaad as a derived basal sauropodomorph closely related to plateosaurid or massospondylid 'prosauropods' and its presence in western North America is not unexpected for a member of this highly cosmopolitan clade. This occurrence represents one of the most complete vertebrate body fossil specimens yet recovered from the Navajo Sandstone and one of the few basal sauropodomorph taxa currently known from North America.
What determines the number of cultural traits present in chimpanzee (Pan troglodytes) communities is poorly understood. In humans, theoretical models suggest that the frequency of cultural traits can be predicted by population size. In chimpanzees, however, females seem to have a particularly important role as cultural carriers. Female chimpanzees use tools more frequently than males. They also spend more time with their young, skewing the infants' potential for social learning towards their mothers. In Gombe, termite fishing has been shown to be transmitted from mother to offspring. Lastly, it is female chimpanzees that transfer between communities and thus have the possibility of bringing in novel cultural traits from other communities. From these observations we predicted that females are more important cultural carriers than males. Here we show that the reported number of cultural traits in chimpanzee communities correlates with the number of females in chimpanzee communities, but not with the number of males. Hence, our results suggest that females are the carriers of chimpanzee culture.
Animals captive bred for reintroduction are often housed under conditions which are not representative of their preferred social structure for at least part of the reintroduction process. Specifically, this is most likely to occur during the final stages of the release programme, whilst being housed during transportation to the release site. The degree of social stress experienced by individuals during this time may negatively impact upon their immunocompetence. We examined two measure of stress - body weight and Leukocyte Coping Capacity (LCC) - to investigate the effects of group size upon captive-bred water voles destined for release within a reintroduction program. Water voles were housed in laboratory cages containing between one and eight individuals. LCC scores were negatively correlated with group size, suggesting that individuals in larger groups experienced a larger degree of immuno-suppression than did individuals housed in smaller groups or individually. During the course of the study mean body weights increased, in contrast to expectations from a previous study. This was attributed to the individuals sampled being sub-adults and thus growing in length and weight during the course of the investigation. The reintroduction process will inevitably cause some stress to the release cohort. However, for water voles we conclude that the stress experienced may be reduced by decreasing group size within captive colony and/or transportation housing practises. These findings are of significance to other species' reintroductions, in highlighting the need to consider life-history strategies when choosing housing systems for animals being maintained in captivity prior to release to the wild. A reduction in stress experienced at the pre-release stage may improve immunocompetence and thus animal welfare and initial survival post-release.
Although being an important source of science news information to the public, print news media have often been criticized in their credibility. Health-related content of press media articles has been examined by many studies underlining that information about benefits, risks and costs are often incomplete or inadequate and financial conflicts of interest are rarely reported. However, these studies have focused their analysis on very selected science articles. The present research aimed at adopting a wider explorative approach, by analysing all types of health science information appearing on the Italian national press in one-week period. Moreover, we attempted to score the balance of the articles. We collected 146 health science communication articles defined as articles aiming at improving the reader's knowledge on health from a scientific perspective. Articles were evaluated by 3 independent physicians with respect to different divulgation parameters: benefits, costs, risks, sources of information, disclosure of financial conflicts of interest and balance. Balance was evaluated with regard to exaggerated or non correct claims. The selected articles appeared on 41 Italian national daily newspapers and 41 weekly magazines, representing 89% of national circulation copies: 97 articles (66%) covered common medical treatments or basic scientific research and 49 (34%) were about new medical treatments, procedures, tests or products. We found that only 6/49 (12%) articles on new treatments, procedures, tests or products mentioned costs or risks to patients. Moreover, benefits were always maximized and in 16/49 cases (33%) they were presented in relative rather than absolute terms. The majority of stories (133/146, 91%) did not report any financial conflict of interest. Among these, 15 were shown to underreport them (15/146, 9.5%), as we demonstrated that conflicts of interest did actually exist. Unbalanced articles were 27/146 (18%). Specifically, the probability of unbalanced reporting was significantly increased in stories about a new treatment, procedure, test or product (22/49, 45%), compared to stories covering common treatments or basic scientific research (5/97, 5%) (risk ratio, 8.72). Consistent with prior research on health science communication in other countries, we report undisclosed costs and risks, emphasized benefits, unrevealed financial conflicts of interest and exaggerated claims in Italian print media. In addition, we show that the risk for a story about a new medical approach to be unbalanced is almost 9 times higher with respect to stories about any other kind of health science-related topics. These findings raise again the fundamental issue whether popular media is detrimental rather than useful to public health.
Molecular feedback loops involving transcription and translation and several key genes are at the core of circadian regulatory cycles affecting cellular pathways and metabolism. These cycles are active in most adult animal cells but little is known about their expression or influence during development. To determine if circadian cycles are active during mammalian development we measured the expression of key circadian genes during embryogenesis in mice using quantitative real-time RT-PCR. All of the genes examined were expressed in whole embryos beginning at the earliest age examined, embryonic day 10. In contrast to adult tissues, circadian variation was absent for all genes at all of the embryonic ages examined in either whole embryos or individual tissues. Using a bioluminescent fusion protein that tracks translation of the circadian gene, per2, we also analyzed protein levels. Similar to mRNA, a protein rhythm was observed in adult tissue but not in embryonic tissues collected in-vivo. In contrast, when tissues were placed in culture for the continuous assay of bioluminescence, rhythms were observed in embryonic (E18) tissues. We found that placing embryonic tissues in culture set the timing (phase) of these rhythms, suggesting the importance of a synchronizing signal for the expression of circadian cycles in developing tissues. These results show that embryonic tissues express key circadian genes and have the capacity to express active circadian regulatory cycles. In vivo, circadian cycles are not expressed in embryonic tissues as they are in adult tissues. Individual cells might express oscillations, but are not synchronized until later in development.
The contents of pharmaceutical industry sponsored supplements to medical journals are perceived to be less credible than the contents of their parent journals. It is unknown if their contents are cited as often. The objective of this study was to quantify the citability of original research and reviews contained in supplements and compare it with that for the parent journal. This was a cohort study of 446 articles published in the Journal of Clinical Psychiatry (JCP) and its supplements for calendar years 2000 and 2005. The total citation counts for each article up to October 5, 2009 were retrieved from the ISI Web of Science database. The main outcome measure was the number of citations received by an article since publication. Regular journal articles included 114 from calendar year 2000 and 190 from 2005. Articles from supplements included 90 from 2000 and 52 from 2005. The median citation counts for the 3 years post-publication were 10 (interquartile range [IQR], 4-20), 14 (IQR, 8-20), 13.5 (IQR, 8-23), and 13.5 (IQR, 8-20), for the 2000 parent journal, 2000 supplements, 2005 parent journal, and 2005 supplements, respectively. Citation counts were higher for the articles in the supplements than the parent journal for the cohorts from 2000 (p = .02), and no different for the year 2005 cohorts (p = .88). The 2005 parent journal cohort had higher citation counts than the 2000 cohort (p = .007), in contrast to the supplements where citation counts remained the same (p = .94). Articles published in JCP supplements are robustly cited and thus can be influential in guiding clinical and research practice, as well as shaping critical thinking. Because they are printed under the sponsorship of commercial interests, they may be perceived as less than objective. A reasonable step to help improve this perception would be to ensure that supplements are peer-reviewed in the same way as regular articles in the parent journal.
Another great round of articles! Mark Loewen, one of the authors on the new dinosaur, certainly has taken advantage of the blogosphere in discussing the work. There are interviews with him at my blog, The Open Source Paleontologist, as well as at Dave Hone's Archosaur Musings. Mark provides some neat behind-the-scenes details that didn't make it into any of the press releases or the published paper.