838 research outputs found

    Physiological Effects of Estradiol in the Mouse Hippocampal Formation

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    At several points in a woman’s life, changes in circulating estradiol are associated with disturbances in mood and cognitive function. To determine the biological basis of these behavioral changes, researchers have concentrated on the hippocampal formation, a medial temporal lobe structure involved in the regulation of mood and cognition in humans. It is now clear that estradiol increases the substrates of hippocampal synaptic plasticity, including dendritic spine density, synapse density, and synaptic protein expression. In some cases, these changes are associated with alterations in mood and hippocampal-dependent learning and memory. The upstream mediators of these estradiol effects remain unknown, but likely candidates may be inferred from known regulators of hippocampal synaptic plasticity and estradiol effects in other tissues. This thesis explored estradiol activation of two of these candidates, PI3 kinase/Akt and brain-derived neurotrophic factor (BDNF), in the dorsal hippocampus of female mice. In naturally cycling and ovariectomized female mice, estradiol increased hippocampal Akt and BDNF signaling as determined by immunocytochemistry and in situ hybridization. These effects were associated with changes in synaptic protein expression, and required specific estrogen receptor isoforms, as demonstrated using estrogen receptor knockout mice. Immuno-electron microscopy revealed that estradiol specifically increased signaling through presynaptic TrkB receptors in Schaffer collateral and mossy fiber axons. Estradiol effects on Akt signaling were associated with changes in spatial memory ability, and were profoundly altered in mice expressing the BDNF variant Val66Met. This study therefore identifies Akt and BDNF signaling as important upstream pathways in the control of hippocampal function by ovarian steroids in vivo. Circulating estradiol activates Akt rapidly through a BDNF-dependent mechanism, and increases expression of BDNF more slowly, leading to increased activation of the BDNF receptor TrkB. After activation, Akt and TrkB may participate in estradiol regulation of spine synapse density and hippocampal cell excitability. Future studies should aim to understand the specific role of Akt and BDNF in estradiol modulation of hippocampal function and behavior

    Telepsychology deployment during circuit breaker in Singapore: a comparative evaluation of treatment effectiveness

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    Background: The advent of the COVID 19 pandemic and the resulting necessity for physical distancing has resulted in massive and rapid changes in service delivery systems throughout the world. Within health care the delivery of psychological treatment has been similarly affected and this has resulted in widespread adoption of telepsychology models of practice. Telepsychology is the provision psychological services using telecommunications technologies. This presentation examines the possible impact of moving to telepsychology services for clients at a university Psychology Clinic during the Circuit Breaker period in Singapore. Clients who completed treatment at the Psychology Clinic before and after Circuir breaker were compared on three aspects of treatment effectiveness

    Logistic regression models to predict solvent accessible residues using sequence- and homology-based qualitative and quantitative descriptors applied to a domain-complete X-ray structure learning set

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    A working example of relative solvent accessibility (RSA) prediction for proteins is presented. Novel logistic regression models with various qualitative descriptors that include amino acid type and quantitative descriptors that include 20- and six-term sequence entropy have been built and validated. A domain-complete learning set of over 1300 proteins is used to fit initial models with various sequence homology descriptors as well as query residue qualitative descriptors. Homology descriptors are derived from BLASTp sequence alignments, whereas the RSA values are determined directly from the crystal structure. The logistic regression models are fitted using dichotomous responses indicating buried or accessible solvent, with binary classifications obtained from the RSA values. The fitted models determine binary predictions of residue solvent accessibility with accuracies comparable to other less computationally intensive methods using the standard RSA threshold criteria 20 and 25% as solvent accessible. When an additional non-homology descriptor describing Lobanov–Galzitskaya residue disorder propensity is included, incremental improvements in accuracy are achieved with 25% threshold accuracies of 76.12 and 74.45% for the Manesh-215 and CASP(8+9) test sets, respectively. Moreover, the described software and the accompanying learning and validation sets allow students and researchers to explore the utility of RSA prediction with simple, physically intuitive models in any number of related applications

    Corticosterone enhances formation of non-fear but not fear memory during infectious illness

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    IntroductionSurvivors of critical illness are at high risk of developing post-traumatic stress disorder (PTSD) but administration of glucocorticoids during the illness can lower that risk. The mechanism is not known but may involve glucocorticoid modulation of hippocampal- and amygdala-dependent memory formation. In this study, we sought to determine whether glucocorticoids given during an acute illness influence the formation and persistence of fear and non-fear memories from the time of the illness.MethodsWe performed cecal ligation and puncture in male and female mice to induce an acute infectious illness. During the illness, mice were introduced to a neutral object in their home cage and separately underwent contextual fear conditioning. We then tested the persistence of object and fear memories after recovery.ResultsGlucocorticoid treatment enhanced object discrimination but did not alter the expression of contextual fear memory. During context re-exposure, neural activity was elevated in the dentate gyrus irrespective of fear conditioning.ConclusionsOur results suggest that glucocorticoids given during illness enhance hippocampal-dependent non-fear memory processes. This indicates that PTSD outcomes in critically ill patients may be improved by enhancing non-fear memories from the time of their illness

    CARMA CO(J = 2 - 1) Observations of the Circumstellar Envelope of Betelgeuse

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    We report radio interferometric observations of the 12C16O 1.3 mm J = 2-1 emission line in the circumstellar envelope of the M supergiant Alpha Ori and have detected and separated both the S1 and S2 flow components for the first time. Observations were made with the Combined Array for Research in Millimeter-wave Astronomy (CARMA) interferometer in the C, D, and E antenna configurations. We obtain good u-v coverage (5-280 klambda) by combining data from all three configurations allowing us to trace spatial scales as small as 0.9\arcsec over a 32\arcsec field of view. The high spectral and spatial resolution C configuration line profile shows that the inner S1 flow has slightly asymmetric outflow velocities ranging from -9.0 km s-1 to +10.6 km s-1 with respect to the stellar rest frame. We find little evidence for the outer S2 flow in this configuration because the majority of this emission has been spatially-filtered (resolved out) by the array. We also report a SOFIA-GREAT CO(J= 12-11) emission line profile which we associate with this inner higher excitation S1 flow. The outer S2 flow appears in the D and E configuration maps and its outflow velocity is found to be in good agreement with high resolution optical spectroscopy of K I obtained at the McDonald Observatory. We image both S1 and S2 in the multi-configuration maps and see a gradual change in the angular size of the emission in the high absolute velocity maps. We assign an outer radius of 4\arcsec to S1 and propose that S2 extends beyond CARMA's field of view (32\arcsec at 1.3 mm) out to a radius of 17\arcsec which is larger than recent single-dish observations have indicated. When azimuthally averaged, the intensity fall-off for both flows is found to be proportional to R^{-1}, where R is the projected radius, indicating optically thin winds with \rho \propto R^{-2}.Comment: 11 pages, 8 figures To be published in the Astronomical Journal (Received 2012 February 10; accepted 2012 May 25

    What is the impact of structural and cultural factors and interventions within educational settings on promoting positive mental health and preventing poor mental health: a systematic review

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    Mental health (MH) difficulties are on the increase among children and young people (CYP). Evidence has shown that educational settings contain both risk and protective factors for MH. This review investigated which structural and cultural factors and interventions within educational settings promote positive MH and prevent poor MH in 4-18 year olds. Searches were conducted in PsychINFO, Embase, ERIC, ASSIA and British Education Index, and reference lists from key studies and relevant systematic reviews were hand-searched. Intervention, cohort, and qualitative studies were included. Of the 62 included papers, 36 examined cultural factors (30 social/relational and six value-related) while 12 studies examined structural factors (eight organisational and four physical) and 14 studies examined multiple factors. There was strong evidence for the impact of positive classroom management techniques, access to physical activity, and peer mentoring on student MH. Studies examining the impact of positive school culture, teacher training in MH and parent involvement in school MH activities also found predominantly positive results for student MH, albeit the evidence was of lower quality or from a low number of studies. Few studies explicitly examined the impact of interventions on MH inequalities; those that did indicated limited if any reduction to inequalities. A very small number of studies suggested that interventions targeting those at risk of poor MH due to socioeconomic factors could successfully improve wellbeing and reduce depression, anxiety and behavioural problems. Studies exploring the effect of management and leadership strategies within schools, policies, and aspects of the physical environment other than green space were scarce or absent in the literature. This review highlights the need to consider the ways in which educational settings are organised, the culture that is created and the physical space in order to improve the MH of CYP

    Composition and content of phenolic acids and avenanthramides in commercial oat products: are oats an important polyphenol source for consumers?

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    Oats contain a range of phenolic acids and avenanthramides which may have health benefits. Analysis of 22 commercial oat products (oat bran concentrate, oat bran, flaked oats, rolled oats and oatcakes) using HPLC-DAD detected eleven bound and thirteen free + conjugated phenolic acids and avenanthramides. The oat products (excluding concentrate) provided between 15.79 and 25.05 mg total phenolic acids (9.9–19.33 mg bound, 4.96–5.72 mg free + conjugated) and between 1.1 and 2 mg of avenanthramides in a 40 g portion while an 11 g portion of oat concentrate provided 16.7 mg of total phenolic acids (15.17 mg bound, 1.53 mg free + conjugated) and 1.2 mg of avenanthramides. The compositions and concentrations of the components in the different products were broadly similar, with the major component being ferulic acid (58–78.1%). The results show that commercial oat products are a source of phenolic acids and avenanthramides for consumers

    The Iowa Homemaker vol.1, no.9

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    Table of Contents Aunt Sarah’s Portrait and the Frame that Matched by Ruth Safford, page 1 Hymns for Christmas Day and Every Day by Eda Lord Murphy, page 2 Buffet Service Makes Holiday Entertainment Easy by Helen Paschal, page 3 The Art of Framing and Hanging Pictures by Joanna M. Hansen, page 4 Christmas Gifts From My Christmas Paint Shop by Mildred Elder, page 5 Home Made Toys for Tiny Tots by Clara Jordan, page 6 By Her Clothes You Shall Know Her by Ruth Spencer, page 7 Why Not a Christmas Plum Pudding Sale? by Willetta Moore, page 8 Christmas Sweets You Will Want to Make by Beth Bailey, page 8 A Unique Nutrition Clinic by Ione Johnson, page 1

    Recombination landscape dimorphism and sex chromosome evolution in the dioecious plant Rumex hastatulus

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    There is growing evidence from diverse taxa for sex differences in the genomic landscape of recombination, but the causes and consequences of these differences remain poorly understood. Strong recombination landscape dimorphism between the sexes could have important implications for the dynamics of sex chromosome evolution because low recombination in the heterogametic sex can favour the spread of sexually antagonistic alleles. Here, we present a sex-specific linkage map and revised genome assembly of Rumex hastatulus and provide the first evidence and characterization of sex differences in recombination landscape in a dioecious plant. We present data on significant sex differences in recombination, with regions of very low recombination in males covering over half of the genome. This pattern is evident on both sex chromosomes and autosomes, suggesting that pre-existing differences in recombination may have contributed to sex chromosome formation and divergence. Our analysis of segregation distortion suggests that haploid selection due to pollen competition occurs disproportionately in regions with low male recombination. We hypothesize that sex differences in the recombination landscape have contributed to the formation of a large heteromorphic pair of sex chromosomes in R. hastatulus, but more comparative analyses of recombination will be important to investigate this hypothesis further.This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.Peer reviewe

    Notes from the field: Lessons learned from using ecosystem service approaches to inform real-world decisions

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    While there have been rapid advances in assessments of biodiversity and ecosystem services (BES), a critical remaining challenge is how to move from scientific knowledge to real-world decision making. We offer 6 lessons from our experiences applying new approaches and tools for quantifying BES in 20 pilot demonstrations: (1) Applying a BES approach is most effective in leading to policy change as part of an iterative science-policy process; (2) simple ecological production function models have been useful in a diverse set of decision contexts, across a broad range of biophysical, social, and governance systems. Key limitations of simple models arise at very small scales, and in predicting specific future BES values; (3) training local experts in the approaches and tools is important for building local capacity, ownership, trust, and long-term success; (4) decision makers and stakeholders prefer to use a variety of BES value metrics, not only monetary values; (5) an important science gap exists in linking changes in BES to changes in livelihoods, health, cultural values, and other metrics of human wellbeing; and (6) communicating uncertainty in useful and transparent ways remains challenging
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