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The King Abdullah Canal (KAC) is an artificial water conveyor serving as raw water source for drinking water supply of Amman and for irrigation purposes in the Jordan Valley. The main water sources for KAC originate from the Yarmouk River, the Mukheiba Wells, and the Peace Conveyor. Water samples were collected from December 2002 to May 2004 to investigate changes in physicochemical parameters and parameters related to eutrophication along KAC. The catchment area of KAC is highly heterogeneous in terms of topography, climate, geologic conditions, and land use, resulting in great variations in the physicochemical composition of the canal water. The Yarmouk River and the Mukheiba Wells reflect the water quality of precipitation without much dissolution of halides, whereas the Peace Conveyor shows a groundwater characteristic. Main dischargers of N and P compounds are the Yarmouk River, and dams and wadis along KAC. The concentrations in the canal are mostly above eutrophication level for N and P. Along KAC there is an increase in chlorophyll a concentration and plankton counts. The formation potentials for trihalomethanes (THMs) and for integrated organically bound halogens are determined by chlorination to evaluate the consequences of water disinfection. Due to relatively high bromide concentration mainly brominated THMs are formed.  相似文献   
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Foreign object ingestion is a common reason for visiting an emergency department; however, wire grill-cleaning brush bristles are an uncommon foreign object. This report describes a series of twelve cases identified in a single hospital system from July 2009 through June 2012. Patients included six males and six females; ages ranged from 11 to 75 (mean: 47 years). The patients all reported recent outdoor residential food grilling and use of commercially available wire grill-cleaning brushes. The severity of injury ranged from puncture of the soft tissues of the neck, causing severe pain on swallowing, to perforation of the gastrointestinal tract requiring emergent surgery. Before cooking, persons should examine the grill surface carefully for the presence of wire bristles that might have dislodged from the grill brush and could embed in cooked food. Alternative residential grill-cleaning methods or products might be considered.  相似文献   
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Herbarium specimens are increasingly recognized as an important resource for conservation science and virtual herbaria are making specimens freely available to a wider range of users than ever before. Few virtual herbaria are designed with conservation use as a primary driver. Exceptionally, Brazil's Reflora Virtual Herbarium (RVH) was created to increase knowledge and conservation of the Brazilian flora. The RVH is closely integrated with the Flora of Brazil 2020 platform on which Brazil's new national Flora is under construction. Both resources are accessible via the Reflora home page and thousands of users move seamlessly between these Reflora resources. To understand how the Reflora resources are currently used and their impact on conservation science, we conducted a literature review and an online survey. We searched for publications of studies in which Reflora resources were used and publications resulting from Brazilian researchers who were part of Reflora's research and mobility program. The survey contained multiple choice questions and questions that required a written response. We targeted Reflora webpage visitors with the survey to capture a wider range of Reflora users than the literature review. Reflora resources were used for a variety of conservation-relevant purposes. Half the 806 scientific publications in which Reflora was cited and 81% of the 1069 survey respondents accessing Reflora resources mentioned conservation-relevant research outputs. Most conservation-relevant uses of the Reflora resources in scientific publications were research rather than implementation focused. The survey of Reflora users showed conservation uses and impacts of virtual herbaria were more numerous and diverse than the uses captured in the literature review. Virtual herbaria are vital resources for conservation science, but they must document use and impacts more comprehensively to ensure sustainability.  相似文献   
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