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To assess and describe the use of rabies post‐exposure prophylaxis (PEP) related to mass bat exposures (MBEs) in the literature and in the state of Rhode Island. Data on MBE events occurring between 2010 and 2016 from the Rhode Island Department of Health (RIDOH) were reviewed to determine PEP usage. For comparison, a systematic review was also performed by searching PubMed, EMBASE, Cochrane Library and Web of Science using the keywords ‘rabies,’ ‘bat’ and ‘exposure.’ There were three MBE events in Rhode Island between 2010 and 2016 in which groups of individuals were asleep during the potential exposure. As a result, RIDOH provided PEP to those involved in the event. In a systematic review of 12 published reports, a variety of settings were involved in MBEs: camping sites, a domestic flight, a neonatal intensive care unit and dormitories. The number of potential rabies exposures ranged from five to 1,429 people. PEP recommendations for assessed persons ranged from 0% to 100% across events (median 21%). The variation in PEP recommendations following a MBE may be dependent on medical need, past precedent or preference. Federal guidance for MBE is needed to add clarity and to minimize the variability in PEP recommendations for such events in the future.  相似文献   
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Type Ia supernovae are important cosmological distance indicators. Each of these bright supernovae supposedly results from the thermonuclear explosion of a white dwarf star that, after accreting material from a companion star, exceeds some mass limit, but the true nature of the progenitor star system remains controversial. Here we report the spectroscopic detection of circumstellar material in a normal type Ia supernova explosion. The expansion velocities, densities, and dimensions of the circumstellar envelope indicate that this material was ejected from the progenitor system. In particular, the relatively low expansion velocities suggest that the white dwarf was accreting material from a companion star that was in the red-giant phase at the time of the explosion.  相似文献   
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Type Ia supernovae are key tools for measuring distances on a cosmic scale. They are generally thought to be the thermonuclear explosion of an accreting white dwarf in a close binary system. The nature of the mass donor is still uncertain. In the single-degenerate model it is a main-sequence star or an evolved star, whereas in the double-degenerate model it is another white dwarf. We show that the velocity structure of absorbing material along the line of sight to 35 type Ia supernovae tends to be blueshifted. These structures are likely signatures of gas outflows from the supernova progenitor systems. Thus, many type Ia supernovae in nearby spiral galaxies may originate in single-degenerate systems.  相似文献   
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High performance liquid chromatography (HPLC) on a calcium form cation exchange column with refractive index and photodiode array detection was used to investigate thermal decomposition as the cause of the loss of crystalline structure in sucrose. Crystalline sucrose structure was removed using a standard differential scanning calorimetry (SDSC) method (fast heating method) and a quasi-isothermal modulated differential scanning calorimetry (MDSC) method (slow heating method). In the fast heating method, initial decomposition components, glucose (0.365%) and 5-HMF (0.003%), were found in the sucrose sample coincident with the onset temperature of the first endothermic peak. In the slow heating method, glucose (0.411%) and 5-HMF (0.003%) were found in the sucrose sample coincident with the holding time (50 min) at which the reversing heat capacity began to increase. In both methods, even before the crystalline structure in sucrose was completely removed, unidentified thermal decomposition components were formed. These results prove not only that the loss of crystalline structure in sucrose is caused by thermal decomposition, but also that it is achieved via a time-temperature combination process. This knowledge is important for quality assurance purposes and for developing new sugar based food and pharmaceutical products. In addition, this research provides new insights into the caramelization process, showing that caramelization can occur under low temperature (significantly below the literature reported melting temperature), albeit longer time, conditions.  相似文献   
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A single gene, fis(+), is essential for induced haploid fruiting in Schizophyllum commune. It appears to segregate independently of the incompatibility factors.  相似文献   
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