968 research outputs found

    A Candidate Subspecies Discrimination System Involving a Vomeronasal Receptor Gene with Different Alleles Fixed in \u3ci\u3eM. m. domesticus\u3c/i\u3e and \u3ci\u3eM. m. musculus\u3c/i\u3e

    Get PDF
    Assortative mating, a potentially efficient prezygotic reproductive barrier, may prevent loss of genetic potential by avoiding the production of unfit hybrids (i.e., because of hybrid infertility or hybrid breakdown) that occur at regions of secondary contact between incipient species. In the case of the mouse hybrid zone, where two subspecies of Mus musculus (M. m. domesticus and M. m. musculus) meet and exchange genes to a limited extent, assortative mating requires a means of subspecies recognition. We based the work reported here on the hypothesis that, if there is a pheromone sufficiently diverged between M. m. domesticus and M. m. musculus to mediate subspecies recognition, then that process must also require a specific receptor(s), also sufficiently diverged between the subspecies, to receive the signal and elicit an assortative mating response. We studied the mouse V1R genes, which encode a large family of receptors in the vomeronasal organ (VNO), by screening Perlegen SNP data and identified one, Vmn1r67, with 24 fixed SNP differences most of which (15/24) are nonsynonymous nucleotide substitutions between M. m. domesticus and M. m. musculus. We observed substantial linkage disequilibrium (LD) between Vmn1r67 and Abpa27, a mouse salivary androgen-binding protein gene that encodes a proteinaceous pheromone (ABP) capable of mediating assortative mating, perhaps in conjunction with its bound small lipophilic ligand. The LD we observed is likely a case of association rather than residual physical linkage from a very recent selective sweep, because an intervening gene, Vmn1r71, shows significant intra(sub)specific polymorphism but no inter(sub)specific divergence in its nucleotide sequence. We discuss alternative explanations of these observations, for example that Abpa27 and Vmn1r67 are coevolving as signal and receptor to reinforce subspecies hybridization barriers or that the unusually divergent Vmn1r67 allele was not a product of fast positive selection, but was derived from an introgressed allele, possibly from Mus spretus

    Collaborations in Liberal Arts Colleges in Support of Digital Humanities

    Get PDF
    The field of digital humanities has been rapidly expanding over the course of the last decade. As such, academic institutions have been working to identify ways of supporting these new endeavors in a time of economic struggles. The Digital Humanities Initiative (DHi) at Hamilton College was conceived as one possible model of supporting digital humanities scholarship at a liberal arts institution. The DHi model relies heavily on collaboration among different teams in the Library and Information Technology Services across campus, and with institutions across the United States. DHi also has international partnerships that promote its goals in research, learning, and public humanities. This chapter will describe the various collaborations of DHi and offer suggestions for how others can implement similar support models at their institutions

    Comparison of cloud microphysical parameters derived from surface and satellite measurements during FIRE phase 2

    Get PDF
    Cloud microphysical properties are an important component in climate model parameterizations of water transport, cloud radiative exchange, and latent heat processes. Estimation of effective cloud particle size, liquid or ice water content, and optical depth from satellite-based instrumentation is needed to develop a climatology of cloud microphysical properties and to better understand and model cloud processes in atmospheric circulation. These parameters are estimated from two different surface data sets taken at Coffeyville, Kansas, during the First ISCCP Regional Experiment (FIRE) Phase-2 Intensive Field Observation (IFO) period (November 13 - December 7, 1991). Satellite data can also provide information about optical depth and effective particle size. This paper explores the combination of the FIRE-2 surface and satellite data to determine each of the cloud microphysical properties

    Uncertainty and fears around sustainability:a qualitative exploration of the emotional reactions of dental practitioners and dental care professionals during COVID-19

    Get PDF
    INTRODUCTION: Recent cross-sectional surveys have shown the detrimental impact of COVID-19 on the health and well-being of dental practitioners and dental care professionals. This qualitative study complements the growing quantitative evidence base with an in-depth exploration of the lived experiences of those working in primary care dental teams in Scotland. METHODS: Focus groups were carried out with primary care dental team members and trainees between July and October 2020. Olsen's tripartite framework of health service sustainability was operationalised to explore how participants experienced uncertainty and their attempts to sustain dental services. RESULTS: Analysis revealed significant concerns surrounding the sustainability of dental services and dental training programmes as a consequence of the emergency level response to the pandemic. Restrictions on dentistry were seen to be severely impeding desirable clinical outcomes, particularly for the most vulnerable groups. Participants experienced being unable to deliver high quality care to their patients as both confusing and distressing. The capability of the dental health care system to meet a growing backlog of dental need and manage this effectively in a pandemic era was called in to serious question. Ongoing uncertainties were affecting how participants were thinking about their professional futures, with stress about income and employment, along with heightened experiences of professional isolation during the pandemic, resulting in some looking at possibilities for retraining or even considering leaving their profession altogether. DISCUSSION: The impact of the pandemic has produced considerable uncertainty regarding the sustainability of dental services in the medium to longer term. It has also served to expose the uncertainties practitioners grapple with routinely as they attempt to sustain their NHS dental service delivery. CONCLUSION: This study brings in to sharp focus the diversity of challenges, confusions and uncertainties experienced by dental practitioners and dental care professionals during the COVID-19 pandemic and the need for suitable and ongoing measures to be put in place to support their mental well-being

    Exploring the Effect of the COVID-19 Pandemic on the Dental Team:Preparedness, Psychological Impacts and Emotional Reactions

    Get PDF
    The work was supported by NHS Education Scotland and University of St Andrews provided the open access publication fee.Background: The COVID-19 pandemic has placed increased demands on clinical staff in primary dental care due to a variety of uncertainties. Current reports on staff responses have tended to be brief enquiries without some theoretical explanation supported by developed measurement systems. Aim: To investigate features of health and well-being as an outcome of the uncertainties surrounding COVID-19 for dentists and dental health professionals in primary dental care and for those in training. In addition, the study examined the well-being indices with reference to normative values. Finally a theoretical model was explored to explain depressive symptoms and investigate its generalisability across dentists and dental health professionals in primary dental care and those in postgraduate training. Methods: A cross-sectional survey of dental trainees and primary dental care staff in Scotland was conducted in June to October 2020. Assessment was through “Portal,” an online tool used for course bookings/management administered by NHS Education for Scotland. A non-probability convenience sample was employed to recruit participants. The questionnaire consisted of four multi-item scales including: preparedness (14 items of the DPPPS), burnout (the 9 item emotional exhaustion subscale and 5 items of the depersonalisation subscale of the MBI), the 22 item Impact of Event Scale-Revised, and depressive symptomatology using the Patient Health Questionnaire-2. Analysis was performed to compare the levels of these assessments between trainees and primary dental care staff and a theoretically based path model to explain depressive symptomology, utilising structural equation modelling. Results: Approximately, 27% of all 329 respondents reported significant depressive symptomology and 55% of primary care staff rated themselves as emotionally exhausted. Primary care staff (n = 218) felt less prepared for managing their health, coping with uncertainty and financial insecurity compared with their trainee (n = 111) counterparts (all p's < 0.05). Depressive symptomology was rated higher than reported community samples (p < 0.05) The overall fit of the raw data applied to the theoretical model confirmed that preparedness (negative association) and trauma associated with COVID-19 (positive association) were significant factors predicting lowered mood (chi-square = 46.7, df = 21, p = 0.001; CFI = 0.98, RMSEA = 0.06, SRMR = 0.03). Burnout was indirectly implicated and a major path from trauma to burnout was found to be significant in primary care staff but absent in trainees (p < 0.002). Conclusion: These initial findings demonstrate the possible benefit of resourcing staff support and interventions to assist dental staff to prepare during periods of high uncertainty resulting from the recent COVID-19 pandemic.Publisher PDFPeer reviewe

    Seasonal prediction of bottom temperature on the Northeast U.S. Continental Shelf

    Get PDF
    © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chen, Z., Kwon, Y.-O., Chen, K., Fratantoni, P., Gawarkiewicz, G., Joyce, T. M., Miller, T. J., Nye, J. A., Saba, V. S., & Stock, B. C. Seasonal prediction of bottom temperature on the Northeast U.S. Continental Shelf. Journal of Geophysical Research: Oceans, 126(5), (2021): e2021JC017187, https://doi.org/10.1029/2021JC017187.The Northeast U.S. shelf (NES) is an oceanographically dynamic marine ecosystem and supports some of the most valuable demersal fisheries in the world. A reliable prediction of NES environmental variables, particularly ocean bottom temperature, could lead to a significant improvement in demersal fisheries management. However, the current generation of climate model-based seasonal-to-interannual predictions exhibits limited prediction skill in this continental shelf environment. Here, we have developed a hierarchy of statistical seasonal predictions for NES bottom temperatures using an eddy-resolving ocean reanalysis data set. A simple, damped local persistence prediction model produces significant skill for lead times up to ∼5 months in the Mid-Atlantic Bight and up to ∼10 months in the Gulf of Maine, although the prediction skill varies notably by season. Considering temperature from a nearby or upstream (i.e., more poleward) region as an additional predictor generally improves prediction skill, presumably as a result of advective processes. Large-scale atmospheric and oceanic indices, such as Gulf Stream path indices (GSIs) and the North Atlantic Oscillation Index, are also tested as predictors for NES bottom temperatures. Only the GSI constructed from temperature observed at 200 m depth significantly improves the prediction skill relative to local persistence. However, the prediction skill from this GSI is not larger than that gained using models incorporating nearby or upstream shelf/slope temperatures. Based on these results, a simplified statistical model has been developed, which can be tailored to fisheries management for the NES.This work was supported by NOAA's Climate Program Office's Modeling, Analysis, Predictions, and Projections (MAPP) Program (NA17OAR4310111, NA19OAR4320074), and Climate Program Office's Climate Variability and Predictability (CVP) Program (NA20OAR4310482). We acknowledge our participation in MAPP's Marine Prediction Task Force

    B806: Performance Evaluations of Potato Clones and Varieties in the Northeastern States 1984

    Get PDF
    Cooperative potato clone and variety trials were conducted at 32 locations to determine field performance of selected clones and varieties grown under soil, climatic, and cultural management common to the potato growing areas of 12 cooperating states and the Province of New Brunswick, Canada. A few locations also evaluated storage and processing behavior of selected clones and varieties. These tests are contributions to Regional Project NE107 entitled, Breeding and Evaluation of New Potato Clones for the Northeast. The primary objective of this project is to determine clone performance and stability over a wide range of soil, climate, and cultural conditions.https://digitalcommons.library.umaine.edu/aes_bulletin/1117/thumbnail.jp

    Tissue-specific variation in DNA methylation levels along human chromosome 1

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>DNA methylation is a major epigenetic modification important for regulating gene expression and suppressing spurious transcription. Most methods to scan the genome in different tissues for differentially methylated sites have focused on the methylation of CpGs in CpG islands, which are concentrations of CpGs often associated with gene promoters.</p> <p>Results</p> <p>Here, we use a methylation profiling strategy that is predominantly responsive to methylation differences outside of CpG islands. The method compares the yield from two samples of size-selected fragments generated by a methylation-sensitive restriction enzyme. We then profile nine different normal tissues from two human donors relative to spleen using a custom array of genomic clones covering the euchromatic portion of human chromosome 1 and representing 8% of the human genome. We observe gross regional differences in methylation states across chromosome 1 between tissues from the same individual, with the most striking differences detected in the comparison of cerebellum and spleen. Profiles of the same tissue from different donors are strikingly similar, as are the profiles of different lobes of the brain. Comparing our results with published gene expression levels, we find that clones exhibiting extreme ratios reflecting low relative methylation are statistically enriched for genes with high expression ratios, and <it>vice versa</it>, in most pairs of tissues examined.</p> <p>Conclusion</p> <p>The varied patterns of methylation differences detected between tissues by our methylation profiling method reinforce the potential functional significance of regional differences in methylation levels outside of CpG islands.</p

    Nuclear microenvironments: an architectural platform for the convergence and integration of transcriptional regulatory signals

    Get PDF
    Functional interrelationships between the intranuclear organization of nucleic acids and regulatory proteins are obligatory for fidelity of transcriptional activation and repression. In this article, using the Runx/AML/Cbfa transcription factors as a paradigm for linkage between nuclear structure and gene expression we present an overview of growing insight into the dynamic organization and assembly of regulatory machinery for gene expression at microenvironments within the nucleus. We address contributions of nuclear microenvironments to the convergence and integration of regulatory signals that mediate transcription by supporting the combinatorial assembly of regulatory complexes
    corecore