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991.
992.
Current guidelines in the setting of exposures to potentially rabid bats established by the Advisory Committee on Immunization Practices (ACIP) address post‐exposure prophylaxis (PEP) administration in situations where a person may not be aware that a bite or direct contact has occurred and the bat is not available for diagnostic testing. These include instances when a bat is discovered in a room where a person awakens from sleep, is a child without an adult witness, has a mental disability or is intoxicated. The current ACIP guidelines, however, do not address PEP in the setting of multiple persons exposed to a bat or a bat colony, otherwise known as mass bat exposure (MBE) events. Due to a dearth of recommendations for response to these events, the reported reactions by public health agencies have varied widely. To address this perceived limitation, a survey of 45 state public health agencies was conducted to characterize prior experiences with MBE and practices to mitigate the public health risks. In general, most states (69% of the respondents) felt current ACIP guidelines were unclear in MBE scenarios. Thirty‐three of the 45 states reported prior experience with MBE, receiving an average of 16.9 MBE calls per year and an investment of 106.7 person‐hours annually on MBE investigations. PEP criteria, investigation methods and the experts recruited in MBE investigations varied between states. These dissimilarities could reflect differences in experience, scenario and resources. The lack of consistency in state responses to potential mass exposures to a highly fatal disease along with the large contingent of states dissatisfied with current ACIP guidance warrants the development of national guidelines in MBE settings.  相似文献   
993.
994.
Journal of Soils and Sediments - A comparison was made between three chemical methods to predict bioaccessibility of triclosan (TCS), bisphenol A (BPA), and 17α-ethynylestradiol (EE2) in...  相似文献   
995.
Spatial design and analysis are widely used, particularly in field experimentation. However, it is often the case that spatial analysis does not significantly enhance more traditional approaches such as row–column analysis. It is then of interest to gauge the degree of error variance bias that accrues when a spatially designed experiment is analysed as a row–column design. This paper uses uniformity data to study error variance bias in \(7\times 12\) spatial designs for 21 treatments.  相似文献   
996.
The tufted puffin (Fratercula cirrhata) is a generalist seabird that breeds throughout the North Pacific and eats more than 75 different prey species. Using puffins as samplers, we characterized the geographic variability in pelagic food webs across the subarctic North Pacific from the composition of ~10,000 tufted puffin meals (~56,000 prey items) collected at 35 colonies in the Gulf of Alaska (GoA) and Aleutian Archipelago. Cluster analysis of diet species composition suggested three distinct forage fish communities: (i) in the northern GoA, multiple age‐classes of coastal and shelf residents such as capelin, sand lance and herring dominated the food web, (ii) in the western GoA to eastern Aleutians, the shelf community was dominated by transient age‐0 walleye pollock, and (iii) in the western Aleutians, shelf‐edge and mesopelagic forage species such as squid, lanternfish, and Atka mackerel were prevalent. Geographic patterns of abundance of capelin and sand lance in tufted puffin diets were corroborated by independent research fisheries and diets of piscivorous fish, indicating that puffin diets reflect the local abundance of forage species, not just selection of favored species. Generalized additive models showed that habitat characteristics predict, in a non‐linear fashion, forage species distribution and abundance across two large marine ecosystems. We conclude that major biogeographic patterns in forage fish distribution follow gradients in key habitat features, and puffin diets reflect those patterns.  相似文献   
997.
Vitellogenesis is the process of production and uptake of vitellogenin (VtG), the precursor of vitellin (VT = yolk protein), for ovarian development. In Callinectes sapidus, hemolymph VtG levels are positively correlated with ovarian development. We aimed to develop an invasive tool to monitor ovarian development in order to predict spawning. The present study determined the effects of photoperiod and temperature conditions on levels of hemolymph VtG of the females in captivity kept in a closed recirculating system. Hemolymph VtG levels measured using a competitive ELISA correlates positively with temperature (21° versus 11°C) but are negatively correlated with photoperiod (0L:24D and 8L:16D versus 16L:8D and 24L:0D). Also, heavier (larger) females contain more VtG in their hemolymph and produce greater numbers of larvae. At 21°C, the VtG levels show high individual variations and continuously change over time, indicating that VtG production and uptake by ovary may be continuous and dynamic over multiple spawning events in C. sapidus. Microsatellite analysis of these females reveals a great diversity within and between the batches, implying that resident C. sapidus populations in the Chesapeake Bay are genetically dynamic. Such a great genetic diversity could be responsible for the high variation in VtG levels in these females.  相似文献   
998.
The early detection and correct identification of polydorid polychaete species is essential as they are often encountered as invasive alien pests in aquaculture facilities or the intertidal where they may modify the ecosystem. Accurate identification is, however, often hampered by high levels of morphological similarity among species. This taxon will therefore benefit from the development of a library of sequences, such as COI barcodes, to aid identification. However, the universal primers for the cytochrome c oxidase I (COI) DNA barcoding marker has failed to consistently amplify this gene for polydorids, greatly hampering the development of such a library. We describe the development of unique PCR primers for the COI gene that work across four genera and nine species of polydorids. We also compared its efficacy with sequence data for mitochondrial cytochrome b and nuclear 18S rRNA, and a concatenated dataset consisting of all three markers. The nuclear 18S rRNA gene showed the least variation both intra- (0.0–1.2%) and interspecifically (0.6–4.3%), and was the most accurate for species identifications among the three markers. Although COI was characterised by higher intraspecific variation compared with Cyt b (0.0–14.5% and 0.0–4.2%, respectively), Cyt b showed considerably higher levels of interspecific variation (16.6–30.2%) compared with COI (2.2–20.7%). Of the two mitochondrial DNA markers, COI was actually less accurate for species identifications, having suggested two species within Boccardia pseudonatrix that was not supported by the other markers. Overall, the concatenated dataset yielded the most consistent intraspecific groupings, suggesting that this is the most accurate means of identifying polydorids using DNA sequence data. Thus, there may not be a quick and easy way to identify these species accurately using only molecular data.  相似文献   
999.
Agriculture plays a key role in national economies and individual livelihoods in many developing countries, and yet agriculture as a field of study and an occupation remain under-emphasized in many educational systems. In addition, working in agriculture is often perceived as being less desirable than other fields, and not a viable or compelling option for students who have received a post-secondary education. This article explores the historical and contemporary perceptions of agriculture as a field of study and an occupation globally, and applies themes from the literature to analyze primary data from focus groups with international students studying for university degrees in the United States. The article analyzes students’ perceptions and experiences in four countries—Bangladesh, Nepal, Honduras and Haiti—in order to make recommendations about how best to address challenges and develop capacity in agricultural education and employment in low-income countries.  相似文献   
1000.
Background: The diagnosis of canine pancreatitis is challenging. Clinical presentation often includes nonspecific clinical signs, such as vomiting, anorexia, and abdominal discomfort. Increased serum lipase activity can be indicative of pancreatitis; however, it can also be increased with other conditions. An immunoassay for measurement of canine pancreas‐specific lipase in canine serum that would be suitable for commercial application and provide rapid results would be beneficial. Objective: The goal of this study was to validate the Spec cPL assay, a commercially available ELISA for the quantitative measurement of canine pancreas‐specific lipase. Methods: Dynamic range, dilutional linearity, precision, interfering substances, assay stability, and reproducibility were investigated for analytical validation. The method was compared with the reference assay, canine pancreatic lipase immunoreactivity (cPLI), and included evaluation of a sample population of dogs and bias. Results: Analytical validation showed a dynamic range of 36–954 μg/L; good precision (intra‐ and interassay coefficient of variation <12%); absence of interference from lipid, hemoglobin, or bilirubin; 12‐month kit stability; and good reproducibility. Method comparison showed a positive bias relative to the cPLI reference method; however, the bias can be accommodated by adjustment of decision limits. The upper limit of the reference interval for Spec cPL was determined to be 216 μg/L based on the upper 97.5th percentile of results from 93 clinically healthy, kennel‐housed dogs. Conclusions: Validation data demonstrated that the Spec cPL assay provides reproducible results for canine pancreas‐specific lipase. A readily available assay for measurement of this enzyme allows broader clinical utilization of this analytical tool, generating timely results to aid in the diagnosis of canine pancreatitis.  相似文献   
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