Positive selection underlies Faster-Z evolution of gene expression in birds.

The elevated rate of evolution for genes on sex chromosomes compared to autosomes (Fast-X or Fast-Z evolution) can result either from positive selection in the heterogametic sex, or from non-adaptive consequences of reduced relative effective population size. Recent work in birds suggests that Fast-Z of coding sequence is primarily due to relaxed purifying selection resulting from reduced relative effective population size. However, gene sequence and gene expression are often subject to distinct evolutionary pressures, therefore we tested for Fast-Z in gene expression using next-generation RNA-sequencing data from multiple avian species. Similar to studies of Fast-Z in coding sequence, we recover clear signatures of Fast-Z in gene expression, however in contrast to coding sequence, our data indicate that Fast-Z in expression is due to positive selection acting primarily in females. In the soma, where gene expression is highly correlated between the sexes, we detected Fast-Z in both sexes, although at a higher rate in females, suggesting that many positively selected expression changes in females are also expressed in males. In the gonad, where inter-sexual correlations in expression are much lower, we detected Fast-Z for female gene expression, but crucially, not males. This suggests that a large amount of expression variation is sex-specific in its effects within the gonad. Taken together, our results indicate that Fast-Z evolution of gene expression is the product of positive selection acting on recessive beneficial alleles in the heterogametic sex. More broadly, our analysis suggests that the adaptive potential of Z chromosome gene expression may be much greater than that of gene sequence, results which have important implications for the role of sex chromosomes in speciation and sexual selection

Testing the Reward Prediction Error Hypothesis with an Axiomatic Model

Neuroimaging studies typically identify neural activity correlated with the predictions of highly parameterized models, like the many reward prediction error (RPE) models used to study reinforcement learning. Identified brain areas might encode RPEs or, alternatively, only have activity correlated with RPE model predictions. Here, we use an alternate axiomatic approach rooted in economic theory to formally test the entire class of RPE models on neural data. We show that measurements of human neural activity from the striatum, medial prefrontal cortex, amygdala, and posterior cingulate cortex satisfy necessary and sufficient conditions for the entire class of RPE models. However, activity measured from the anterior insula falsifies the axiomatic model, and therefore no RPE model can account for measured activity. Further analysis suggests the anterior insula might instead encode something related to the salience of an outcome. As cognitive neuroscience matures and models proliferate, formal approaches of this kind that assess entire model classes rather than specific model exemplars may take on increased significance

Detection of heat shock protein 70 in choroidal neovascular membranes secondary to age related macular degeneration

<p>Abstract</p> <p>Background</p> <p>Heat shock proteins are acute phase proteins that are upregulated in inflammation or following thermal stress. We analyzed the presence of the heat shock protein 70 (Hsp 70) in choroidal neovascular (CNV) membranes secondary to AMD after treatment with verteporphin photodynamic therapy (PDT) or transpupillary thermo therapy (TTT) to determine whether treatment correlated with the presence of Hsp70.</p> <p>Results</p> <p>CNV membranes were removed by pars plana vitrectomy (ppV) and subretinal extraction. The membranes were analysed by light microscopy and the presence of Hsp 70 was examined using histochemistry. HeLa Cells served as controls.</p> <p>Of the 14 membranes analysed 11 were Hsp70 positive and 3 negative. In the no pre-treatment group of 8 membranes 6 were Hsp70 positive and 2 negative; in the PTD group all 4 membranes were positive and in the TTT group 1 membrane was positive and 1 membrane was negative for Hsp70.</p> <p>Conclusion</p> <p>Hsp70 is present in the most CNV membranes secondary to AMD. Pre-treatment of the membrane with PTD or TTT does not appear to influence the expression of Hsp70.</p

Generic names in Magnaporthales

This is the final version of the article. Available from the publisher via the DOI in this record.The order Magnaporthales comprises about 200 species and includes the economically and scientifically important rice blast fungus and the take-all pathogen of cereals, as well as saprotrophs and endophytes. Recent advances in phylogenetic analyses of these fungi resulted in taxonomic revisions. In this paper we list the 28 currently accepted genera in Magnaporthales with their type species and available gene and genome resources. The polyphyletic Magnaporthe 1972 is proposed for suppression, and Pyricularia 1880 and Nakataea 1939 are recommended for protection as the generic names for the rice blast fungus and the rice stem rot fungus, respectively. The rationale for the recommended names is also provided. These recommendations are made by the Pyricularia/Magnaporthe Working Group established under the auspices of the International Commission on the Taxonomy of Fungi (ICTF).This work was partially supported by the National Science Foundation of the United States (grant number DEB 1145174 and DEB 1452971) to Ning Zhang

Translating clinical training into practice in complex mental health systems: Toward opening the 'Black Box' of implementation

<p>Abstract</p> <p>Background</p> <p>Implementing clinical training in a complex health care system is challenging. This report describes two successive trainings programs in one Veterans Affairs healthcare network and the lessons we drew from their success and failures. The first training experience led us to appreciate the value of careful implementation planning while the second suggested that use of an external facilitator might be an especially effective implementation component. We also describe a third training intervention in which we expect to more rigorously test our hypothesis regarding the value of external facilitation.</p> <p>Results</p> <p>Our experiences appear to be consonant with the implementation model proposed by Fixsen. In this paper we offer a modified version of the Fixsen model with separate components related to training and implementation.</p> <p>Conclusion</p> <p>This report further reinforces what others have noted, namely that educational interventions intended to change clinical practice should employ a multilevel approach if patients are to truly benefit from new skills gained by clinicians. We utilize an implementation research model to illustrate how the aims of the second intervention were realized and sustained over the 12-month follow-up period, and to suggest directions for future implementation research. The present report attests to the validity of, and contributes to, the emerging literature on implementation research.</p

Antecedents and consequences of effectuation and causation in the international new venture creation process

The selection of the entry mode in an international market is of key importance for the venture. A process-based perspective on entry mode selection can add to the International Business and International Entrepreneurship literature. Framing the international market entry as an entrepreneurial process, this paper analyzes the antecedents and consequences of causation and effectuation in the entry mode selection. For the analysis, regression-based techniques were used on a sample of 65 gazelles. The results indicate that experienced entrepreneurs tend to apply effectuation rather than causation, while uncertainty does not have a systematic influence. Entrepreneurs using causation-based international new venture creation processes tend to engage in export-type entry modes, while effectuation-based international new venture creation processes do not predetermine the entry mod

Multisensory information facilitates reaction speed by enlarging activity difference between superior colliculus hemispheres in rats

Animals can make faster behavioral responses to multisensory stimuli than to unisensory stimuli. The superior colliculus (SC), which receives multiple inputs from different sensory modalities, is considered to be involved in the initiation of motor responses. However, the mechanism by which multisensory information facilitates motor responses is not yet understood. Here, we demonstrate that multisensory information modulates competition among SC neurons to elicit faster responses. We conducted multiunit recordings from the SC of rats performing a two-alternative spatial discrimination task using auditory and/or visual stimuli. We found that a large population of SC neurons showed direction-selective activity before the onset of movement in response to the stimuli irrespective of stimulation modality. Trial-by-trial correlation analysis showed that the premovement activity of many SC neurons increased with faster reaction speed for the contraversive movement, whereas the premovement activity of another population of neurons decreased with faster reaction speed for the ipsiversive movement. When visual and auditory stimuli were presented simultaneously, the premovement activity of a population of neurons for the contraversive movement was enhanced, whereas the premovement activity of another population of neurons for the ipsiversive movement was depressed. Unilateral inactivation of SC using muscimol prolonged reaction times of contraversive movements, but it shortened those of ipsiversive movements. These findings suggest that the difference in activity between the SC hemispheres regulates the reaction speed of motor responses, and multisensory information enlarges the activity difference resulting in faster responses

Genomic analysis of Sparus aurata reveals the evolutionary dynamics of sex-biased genes in a sequential hermaphrodite fish

Sexual dimorphism is a fascinating subject in evolutionary biology and mostly results from sex-biased expression of genes, which have been shown to evolve faster in gonochoristic species. We report here genome and sex-specific transcriptome sequencing of Sparus aurata, a sequential hermaphrodite fish. Evolutionary comparative analysis reveals that sex-biased genes in S. aurata are similar in number and function, but evolved following strikingly divergent patterns compared with gonochoristic species, showing overall slower rates because of stronger functional constraints. Fast evolution is observed only for highly ovary-biased genes due to female-specific patterns of selection that are related to the peculiar reproduction mode of S. aurata, first maturing as male, then as female. To our knowledge, these findings represent the first genome-wide analysis on sex-biased loci in a hermaphrodite vertebrate species, demonstrating how having two sexes in the same individual profoundly affects the fate of a large set of evolutionarily relevant genes.European Union KBBE.2013.1.2-10 European Community 311920 Fondazione Cassa di Risparmio Padova e Rovigo FCT - Foundation for Science and Technology research grant SPARCOMP under the Call ARISTEIA I of the National Strategic Reference Framework - by the EU 36 Hellenic Republic through the European Social Fundinfo:eu-repo/semantics/publishedVersio

Quantum criticality in ferroelectrics

Materials tuned to the neighbourhood of a zero temperature phase transition often show the emergence of novel quantum phenomena. Much of the effort to study these new effects, like the breakdown of the conventional Fermi-liquid theory of metals has been focused in narrow band electronic systems. Ferroelectric crystals provide a very different type of quantum criticality that arises purely from the crystalline lattice. In many cases the ferroelectric phase can be tuned to absolute zero using hydrostatic pressure or chemical or isotopic substitution. Close to such a zero temperature phase transition, the dielectric constant and other quantities change into radically unconventional forms due to the quantum fluctuations of the electrical polarization. The simplest ferroelectrics may form a text-book paradigm of quantum criticality in the solid-state as the difficulties found in metals due to a high density of gapless excitations on the Fermi surface are avoided. We present low temperature high precision data demonstrating these effects in pure single crystals of SrTiO3 and KTaO3. We outline a model for describing the physics of ferroelectrics close to quantum criticality and highlight the expected 1/T2 dependence of the dielectric constant measured over a wide temperature range at low temperatures. In the neighbourhood of the quantum critical point we report the emergence of a small frequency independent peak in the dielectric constant at approximately 2K in SrTiO3 and 3K in KTaO3 believed to arise from coupling to acoustic phonons. Looking ahead, we suggest that in ferroelectric materials supporting mobile charge carriers, quantum paraelectric fluctuations may mediate new effective electron-electron interactions giving rise to a number of possible states such as superconductivity.Comment: 10 pages, 4 figure

Graphene Photonics and Optoelectronics

The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential to be in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultra-wide-band tunability. The rise of graphene in photonics and optoelectronics is shown by several recent results, ranging from solar cells and light emitting devices, to touch screens, photodetectors and ultrafast lasers. Here we review the state of the art in this emerging field.Comment: Review Nature Photonics, in pres