3,692 research outputs found

    Low Cost Solar Array Project: Composition Measurements by Analytical Photon Catalysis

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    The applicability of the photon catalysis technique for effecting composition analysis of silicon samples was assessed. Third quarter activities were devoted to the study of impurities in silicon matrices. The evaporation process was shown to be congruent; thus, the spectral analysis of the vapor yields the composition of the bulk sample. Qualitative analysis of metal impurities in silicon was demonstrated e part per million level. Only one atomic spectral interference was noted; however, it is imperative to maintain a leak tight system due to chemical and spectral interferences caused by the presence of even minute amounts of oxygen in the active nitrogen afterglow

    High Angular Resolution Observations of the Collimated Jet Source Associated with a Massive Protostar in IRAS 16547-4247

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    A triple radio source recently detected in association with the luminous infrared source IRAS 16547-4247 has been studied with high angular resolution and high sensitivity with the Very Large Array at 3.6 and 2 cm. Our observations confirm the interpretation that the central object is a thermal radio jet, while the two outer lobes are most probably heavily obscured HH objects. The thermal radio jet is resolved angularly for the first time and found to align closely with the outer lobes. The opening angle of the thermal jet is estimated to be 25\sim 25^\circ, confirming that collimated outflows can also be present in massive protostars. The proper motions of the outer lobes should be measurable over timescales of a few years. Several fainter sources detected in the region are most probably associated with other stars in a young cluster.Comment: 9 pages, 2 figure

    Cross-sectional study of the association between empathy and burnout and drug prescribing quality in primary care

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    Burnout; Empathy; EthicsEsgotament; Empatia; ÈticaAgotamiento; Empatía; ÉticaObjective: The aim of this study was to assess whether burnout and empathy levels among general practitioners (GPs) might influence prescribing performance assessed using pharmaceutical prescription quality standard indicators. Design and Setting: Cross-sectional descriptive study of 108 GPs from 22 primary care centers in Lleida, Spain, and of centralized data corresponding to 183 600 patients under their care. The study was conducted between May and July 2014. Main Outcome Measures: Burnout and empathy were measured using the Spanish versions of the Maslach Burnout Inventory and the Jefferson Scale for Physician Empathy, and prescribing quality was measured using the Catalan Pharmaceutical Prescription Quality Standard (EQPF). Normal distribution of scores was verified using the Chi-square and Kolmogorov–Smirnov–Lilliefors tests. The effect of each of the variables was evaluated using crude odds ratios. Results: Older GPs scored significantly higher in the EQPF (P < 0.05). High empathy scores were positively associated with high EQPF scores. GPs with low burnout also performed better in the EQPF. Conclusions: More empathic, less burned-out, older GPs showed better prescribing performance according to quality indicators. However, further studies are needed to evaluate other factors influencing prescribing habits. The promotion of communication skills may increase empathy and reduce burnout, thus benefiting patients.The authors did not receive any grants for this study. However, previous research in this field was conducted with the support of the Victor Grífols Foundation

    Determination of the Axial-Vector Weak Coupling Constant with Ultracold Neutrons

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    A precise measurement of the neutron decay β\beta-asymmetry A0A_0 has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report A0=0.11966±0.000890.00140+0.00123A_0 = -0.11966 \pm 0.00089_{-0.00140}^{+0.00123}, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon gA/gV=1.275900.00445+0.00409g_A/g_V = -1.27590_{-0.00445}^{+0.00409}.Comment: 5 pages, 2 figure

    A role of mitochondrial complex II defects in genetic models of Huntington's disease expressing N-terminal fragments of mutant huntingtin.

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    Huntington's disease (HD) is a neurodegenerative disorder caused by an abnormal expansion of a CAG repeat encoding a polyglutamine tract in the huntingtin (Htt) protein. The mutation leads to neuronal death through mechanisms which are still unknown. One hypothesis is that mitochondrial defects may play a key role. In support of this, the activity of mitochondrial complex II (C-II) is preferentially reduced in the striatum of HD patients. Here, we studied C-II expression in different genetic models of HD expressing N-terminal fragments of mutant Htt (mHtt). Western blot analysis showed that the expression of the 30 kDa Iron-Sulfur (Ip) subunit of C-II was significantly reduced in the striatum of the R6/1 transgenic mice, while the levels of the FAD containing catalytic 70 kDa subunit (Fp) were not significantly changed. Blue native gel analysis showed that the assembly of C-II in mitochondria was altered early in N171-82Q transgenic mice. Early loco-regional reduction in C-II activity and Ip protein expression was also demonstrated in a rat model of HD using intrastriatal injection of lentiviral vectors encoding mHtt. Infection of the rat striatum with a lentiviral vector coding the C-II Ip or Fp subunits induced a significant overexpression of these proteins that led to significant neuroprotection of striatal neurons against mHtt neurotoxicity. These results obtained in vivo support the hypothesis that structural and functional alterations of C-II induced by mHtt may play a critical role in the degeneration of striatal neurons in HD and that mitochondrial-targeted therapies may be useful in its treatment

    New result for the neutron β\beta-asymmetry parameter A0A_0 from UCNA

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    The neutron β\beta-decay asymmetry parameter A0A_0 defines the correlation between the spin of the neutron and the momentum of the emitted electron, which determines λ=gAgV\lambda=\frac{g_{A}}{g_{V}}, the ratio of the axial-vector to vector weak coupling constants. The UCNA Experiment, located at the Ultracold Neutron facility at the Los Alamos Neutron Science Center, is the first to measure such a correlation coefficient using ultracold neutrons (UCN). Following improvements to the systematic uncertainties and increased statistics, we report the new result A0=0.12054(44)stat(68)systA_0 = -0.12054(44)_{\mathrm{stat}}(68)_{\mathrm{syst}} which yields λgAgV=1.2783(22)\lambda\equiv \frac{g_{A}}{g_{V}}=-1.2783(22). Combination with the previous UCNA result and accounting for correlated systematic uncertainties produces A0=0.12015(34)stat(63)systA_0=-0.12015(34)_{\mathrm{stat}}(63)_{\mathrm{syst}} and λgAgV=1.2772(20)\lambda\equiv \frac{g_{A}}{g_{V}}=-1.2772(20).Comment: 9 pages, 7 figures, updated to as-published versio
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