3,238 research outputs found

    Memory reconsolidation in aversive and appetitive settings

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    Memory reconsolidation has been observed across species and in a number of behavioral paradigms. The majority of memory reconsolidation studies have been carried out in Pavlovian fear conditioning and other aversive memory settings, with potential implications for the treatment of post-traumatic stress disorder. However, there is a growing literature on memory reconsolidation in appetitive reward-related memory paradigms, including translational models of drug addiction. While there appears to be substantial similarity in the basic phenomenon and underlying mechanisms of memory reconsolidation across unconditioned stimulus valence, there are also notable discrepancies. These arise both when comparing aversive to appetitive paradigms and also across different paradigms within the same valence of memory. We review the demonstration of memory reconsolidation across different aversive and appetitive memory paradigms, the commonalities and differences in underlying mechanisms and the conditions under which each memory undergoes reconsolidation. We focus particularly on whether principles derived from the aversive literature are applicable to appetitive settings, and also whether the expanding literature in appetitive paradigms is informative for fear memory reconsolidation

    Wildlife Health Surveillance on the National Bison Range – Monitoring for M. Paratuberculosis in Bison

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    The wildlife health surveillance program on the National Bison Range was designed to assess the presence and prevalence of diseases in wildlife populations. Annual sampling and disease testing has been conducted at the range for decades. Starting in 2000, a statistically derived disease detection model for bison was designed and implemented to enhance detection of several diseases, including M. paratuberculosis. This disease, commonly known as Johne’s disease, is a bacterial intestinal disease that causes diarrhea, severe weight loss, and eventual death in bison and cattle. Targeting analysis of both populations as a whole and the status of individual animals, the program includes; (1) year-round direct observations aimed at detecting acute injuries, chronic conditions, mortalities, and emerging disease, and (2) regular diagnostic laboratory testing for a suite of diseases of particular concern and to evaluate exposure to several viral, parasitic and bacterial diseases common in the cattle industry. Information from direct observation is documented and shared with staff experienced in dealing with injuries, mortalities, and necropsies. Diagnostic analysis depends on routine coordination with our wildlife health office in Bozeman, Montana, by providing guidance concerning disease or other life-threatening conditions, and annual summary analysis of data. This is a long term adaptive process that includes periodically assessing local and regional wildlife threats, updating protocols according to sample results and providing management with necessary information to maintain healthy wildlife populations within a fenced boundary

    Evidence of environmental strains on charge injection in silole based organic light emitting diodes

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    Using d. functional theory (DFT) computations, the authors demonstrated a substantial skeletal relaxation when the structure of 2,5-bis-[4-anthracene-9-yl-phenyl]-1,1-dimethyl-3,4-diphenyl-silole (BAS) is optimized in the gas-phase comparing with the mol. structure detd. from monocrystal x-ray diffraction. The origin of such a relaxation is explained by a strong environmental strains induced by the presence of anthracene entities. Also, the estn. of the frontier orbital levels showed that this structural relaxation affects mainly the LUMO that is lowered of 190 meV in the gas phase. To check if these theor. findings would be confirmed for thin films of BAS, the authors turned to UV photoemission spectroscopy and/or inverse photoemission spectroscopy and electrooptical measurements. The study of the c.d. or voltage and luminance or voltage characteristics of an ITO/PEDOT/BAS/Au device clearly demonstrated a very unusual temp.-dependent behavior. Using a thermally assisted tunnel transfer model, this behavior likely originated from the variation of the electronic affinity of the silole deriv. with the temp. The thermal agitation relaxes the mol. strains in thin films as it is shown when passing from the cryst. to the gas phase. The relaxation of the intramol. thus induces an increase of the electronic affinity and, as a consequence, the more efficient electron injection in org. light-emitting diodes

    Why Didnt I Get The Job? White Nonbeneficiaries Reactions To Affirmative Action And Diversity Programs

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    The purpose of this study was to investigate how justifications for hiring procedures and hiring decisions impact white nonbeneficiaries perceptions of fairness. The results for the procedural and distributive justice hypotheses were strikingly similar. Both the diversity justification and no justification were perceived to be fairer than the affirmative action justification for both procedural and distributive justice. Interestingly, however, the respondents perceived no justification to be fairer than the diversity justification. Of the three different scenarios, no justification was perceived to be the most fair and affirmative action was perceived to be the least fair justification

    Principal Component Analysis of SDSS Stellar Spectra

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    We apply Principal Component Analysis (PCA) to ~100,000 stellar spectra obtained by the Sloan Digital Sky Survey (SDSS). In order to avoid strong non-linear variation of spectra with effective temperature, the sample is binned into 0.02 mag wide intervals of the g-r color (-0.20<g-r<0.90, roughly corresponding to MK spectral types A3 to K3), and PCA is applied independently for each bin. In each color bin, the first four eigenspectra are sufficient to describe the observed spectra within the measurement noise. We discuss correlations of eigencoefficients with metallicity and gravity estimated by the Sloan Extension for Galactic Understanding and Exploration (SEGUE) Stellar Parameters Pipeline. The resulting high signal-to-noise mean spectra and the other three eigenspectra are made publicly available. These data can be used to generate high quality spectra for an arbitrary combination of effective temperature, metallicity, and gravity within the parameter space probed by the SDSS. The SDSS stellar spectroscopic database and the PCA results presented here offer a convenient method to classify new spectra, to search for unusual spectra, to train various spectral classification methods, and to synthesize accurate colors in arbitrary optical bandpasses.Comment: 25 pages, 15 figures, accepted by the Astronomical Journa
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