A novel virus genome discovered in an extreme environment suggests recombination between unrelated groups of RNA and DNA viruses

<p>Abstract</p> <p>Background</p> <p>Viruses are known to be the most abundant organisms on earth, yet little is known about their collective origin and evolutionary history. With exceptionally high rates of genetic mutation and mosaicism, it is not currently possible to resolve deep evolutionary histories of the known major virus groups. Metagenomics offers a potential means of establishing a more comprehensive view of viral evolution as vast amounts of new sequence data becomes available for comparative analysis.</p> <p>Results</p> <p>Bioinformatic analysis of viral metagenomic sequences derived from a hot, acidic lake revealed a circular, putatively single-stranded DNA virus encoding a major capsid protein similar to those found only in single-stranded RNA viruses. The presence and circular configuration of the complete virus genome was confirmed by inverse PCR amplification from native DNA extracted from lake sediment. The virus genome appears to be the result of a RNA-DNA recombination event between two ostensibly unrelated virus groups. Environmental sequence databases were examined for homologous genes arranged in similar configurations and three similar putative virus genomes from marine environments were identified. This result indicates the existence of a widespread but previously undetected group of viruses.</p> <p>Conclusions</p> <p>This unique viral genome carries implications for theories of virus emergence and evolution, as no mechanism for interviral RNA-DNA recombination has yet been identified, and only scant evidence exists that genetic exchange occurs between such distinct virus lineages.</p> <p>Reviewers</p> <p>This article was reviewed by EK, MK (nominated by PF) and AM. For the full reviews, please go to the Reviewers' comments section.</p

Child posttraumatic stress symptoms in an acute injury sample: Patterns of associations among child report, parent report, and child heart rate parameters

Parent–child agreement on measures of child posttraumatic stress disorder (PTSD) is moderate at best, and understanding of this discrepancy is limited. To address this, we conducted an item-level investigation of parent–child symptom agreement to examine the potential influence of parental posttraumatic stress symptoms (PTSS) on parents’ reports of their child's PTSS. We also examined heart rate (HR) indices as possible independent indicators of child PTSD, examining patterns of association with parent versus child report. Parent–child dyads (N = 132, child age: 6–13 years, 91.7% White) were recruited after the child's hospital admission following an acute, single-incident traumatic event. At 1-month posttrauma, questionnaires assessing children's PTSS (self- and parental reports) and parental PTSS were administered. For a subset of participants (n = 70), children's HR recordings were obtained during a trauma narrative task and analyzed. Parent and child reports of child PTSS were weakly positively correlated, r =.25. Parental PTSS were found to be stronger positive predictors of parental reports of child PTSS than the children's own symptom reports, β = 0.60 vs. β = 0.14, and were associated with higher parent-reported child PTSS relative to child reports. Finally, children's self-reported PTSS were associated with HR indices, whereas parent reports were not, βs = −.33–.30 vs. βs = −.15–.01. Taken together, children's self-reported PTSS could be a more accurate reflection of their posttrauma physiological distress than parent reports. The potential influence of parental PTSS on their perceptions of their child's symptoms warrants further consideration

Influence of damping on the vanishing of the electro-optic effect in chiral isotropic media

Using first principles, it is demonstrated that radiative damping alone cannot lead to a nonvanishing electro-optic effect in a chiral isotropic medium. This conclusion is in contrast with that obtained by a calculation in which damping effects are included using the standard phenomenological model. We show that these predictions differ because the phenomenological damping equations are valid only in regions where the frequencies of the applied electromagnetic fields are nearly resonant with the atomic transitions. We also show that collisional damping can lead to a nonvanishing electrooptic effect, but with a strength sufficiently weak that it is unlikely to be observable under realistic laboratory conditions

'An Apotheosis of Well-Being': Durkheim on austerity and double-dip recessions

This article is an attempt to contribute a view on the economic crisis from classical sociology, a voice often missing from the sociological response to the crisis. The work of Émile Durkheim provides a unique perspective here centred on morality and inequality produced in a historical context akin to our neoliberal times. It is argued there are four key points to take from Durkheim’s work. Firstly, that the initial credit crunch can be more fully understood with reference to the economic anomie which Durkheim sees as ‘chronic’ in a time of marketization. Secondly, that this creates an antagonistic relationship between a supposedly self-dependent rich and lazy poor. Thirdly, this conception of self-dependency and individual initiative makes any attempt to regulate the economy akin to sacrilege. Finally, the state is unwilling to intervene due to the emergence of ‘pseudo-democracies’. Therefore, Durkheim’s theory accounts for the initial crisis, austerity and double-dip recessions in a sociological framework. The article concludes by returning to the centrality of morality to the crisis for Durkheim and highlighting the omission of this in contemporary debates

Birefringence of interferential mirrors at normal incidence Experimental and computational study

In this paper we present a review of the existing data on interferential mirror birefringence. We also report new measurements of two sets of mirrors that confirm that mirror phase retardation per reflection decreases when mirror reflectivity increases. We finally developed a computational code to calculate the expected phase retardation per reflection as a function of the total number of layers constituting the mirror. Different cases have been studied and we have compared computational results with the trend of the experimental data. Our study indicates that the origin of the mirror intrinsic birefringence can be ascribed to the reflecting layers close to the substrate.Comment: To be published in Applied Physics

Anatomy and Neurophysiology of the Taste System in Aged Animals a

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72005/1/j.1749-6632.1989.tb20989.x.pd

Parent and child agreement for acute stress disorder, post-traumatic stress disorder and other psychopathology in a prospective study of children and adolescents exposed to single-event trauma

Examining parent-child agreement for Acute Stress Disorder (ASD) and Post-Traumatic Stress Disorder (PTSD) in children and adolescents is essential for informing the assessment of trauma-exposed children, yet no studies have examined this relationship using appropriate statistical techniques. Parent-child agreement for these disorders was examined by structured interview in a prospective study of assault and motor vehicle accident (MVA) child survivors, assessed at 2-4 weeks and 6 months post-trauma. Children were significantly more likely to meet criteria for ASD, as well as other ASD and PTSD symptom clusters, based on their own report than on their parent's report. Parent-child agreement for ASD was poor (Cohen's κ = -.04), but fair for PTSD (Cohen's κ = .21). Agreement ranged widely for other emotional disorders (Cohen's κ = -.07-.64), with generalised anxiety disorder found to have superior parent-child agreement (when assessed by phi coefficients) relative to ASD and PTSD. The findings support the need to directly interview children and adolescents, particularly for the early screening of posttraumatic stress, and suggest that other anxiety disorders may have a clearer presentation post-trauma