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151.
A method was developed for the simultaneous determination of almost 40 pharmaceuticals; including antidepressants, non-steroidal anti-inflammatories, analgesics, hypolipidemics, α- and β-blockers, an anti cancer drug, anti-fungal agents, an opiate, an antibiotic, an anti-coagulant, a diuretic, an anti-anginal and an anti-diabetic compound. This was used to assess the contribution of pharmaceuticals originating from hospital effluents to one of Oslo city's wastewater treatment works. Some pharmaceuticals were found to contribute to more of the wastewater loading than others. 11% of the propranolol entering the wastewater treatment works stems from hospital effluent, approximately 2% of the atenolol, carbemazepine, metaprolol and atorvastatin, and for several other compounds the contribution is less than 1%.This assessment shows that point sources discharges from hospitals typically make a small contribution to the overall pharmaceutical load when compared to municipal areas, however this varies from substance to substance and is not the case when a drug's use is primarily hospital based.  相似文献   
152.
Meierdiercks, Katherine L., James A. Smith, Mary Lynn Baeck, and Andrew J. Miller, 2010. Heterogeneity of Hydrologic Response in Urban Watersheds. Journal of the American Water Resources Association (JAWRA) 46(6):1221–1237. DOI: 10.1111/j.1752-1688.2010.00487.x Abstract: The changing patterns of streamflow associated with urbanization are examined through analyses of discharge and rainfall records for the study watersheds of the Baltimore Ecosystem Study (BES). Analyses utilize a decade (1999-2008) of observations from a dense U.S. Geological Survey stream gaging network and Hydro-NEXRAD radar rainfall fields. The principal study watershed of the BES is Gwynns Falls (171 km2). Focus is given to two Gwynns Falls basins with contrasting patterns and histories of development, Dead Run and Upper Gwynns Falls. The sharp contrasts in streamflow properties between the basins reflect the differences in urban development prior to implementation of stormwater management regulations (much of Dead Run) and development for which stormwater management is an integral part of the hydrologic system (Upper Gwynns Falls). The mean annual runoff in Dead Run (558 mm) is 35% larger than that of Upper Gwynns Falls; larger contrasts in runoff properties typify the “warm season” and are linked to storm event hydrologic response. Spatial heterogeneities in storm event response are reflected in seasonal and diurnal properties of streamflow. Analyses of storm event response are presented for June 2006, during which monthly rainfall over the BES region ranged from less than 150 to more than 500 mm. Baisman Run, the BES forest reference watershed, and Moores Run, a highly urbanized watershed in Baltimore City, provide “end-member” representations of urban impacts on streamflow.  相似文献   
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We describe the finding of cavum veli interpositi (CVI) on fetal ultrasound and MRI and the postnatal MRI and developmental follow-up in two cases. The first case was diagnosed on fetal ultrasound at 33 weeks' gestation and confirmed on fetal MRI. No abnormalities were detected on postnatal examinations and the brain MRI at 1 year of age showed no changes. At 4 years of age, his growth and development were normal. The second case was diagnosed with CVI on fetal ultrasound and MRI at 33.5 weeks' gestation. Postnatal examination showed no abnormalities, and brain MRI at 8 months of age revealed that the CVI was unchanged, but there was a dilated cavum septum pellucidum and cavum vergae. Her growth and development during the first 4 years of life were normal. CVI is a rare fetal ultrasound finding, which seems to be benign. However, further neurodevelopmental follow-up is needed to confirm this observation. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
155.

Introduction

Distraction on cell phones jeopardizes motor-vehicle driver safety, but few studies examine distracted walking. At particular risk are college students, who walk frequently in and near traffic, have increased pedestrian injury rates compared to other age groups, and frequently use cell phones. Method: Using an interactive and immersive virtual environment, two experiments studied the effect of cell phone conversation on distraction of college student pedestrians. In the first, we examined whether pedestrians would display riskier behavior when distracted by a naturalistic cell phone conversation than when undistracted. We also considered whether individual difference factors would moderate the effect of the distraction. In a second experiment, we examined the impact of three forms of distraction on pedestrian safety: (a) engaging in a cell phone conversation, (b) engaging in a cognitively challenging spatial task by phone, and (c) engaging in a cognitively challenging mental arithmetic task by phone. Results: Results revealed that cell phone conversations distracted college pedestrians considerably across all pedestrian safety variables measured, with just one exception. Attention to traffic was not affected by the naturalistic phone conversation in Experiment 1, but was altered by the cognitively-demanding content of some types of conversation in Experiment 2. The content of the conversation did not play a major role in distraction across other variables; both mundane and cognitively complex conversations distracted participants. Moreover, no significant associations between individual difference factors and susceptibility to distraction emerged. Impact on Industry: Results may inform researchers, policy makers, and pedestrians themselves. Educational campaigns might discourage telephone conversations in pedestrian environments.  相似文献   
156.
Roach KA  Tobler M  Winemiller KO 《Ecology》2011,92(11):2056-2062
Photoautotrophs are generally considered to be the base of food webs, and habitats that lack light, such as caves, frequently rely on surface-derived carbon. Here we show, based on analysis of gut contents and stable isotope ratios of tissues (13C:12C and 15N:14N), that sulfur-oxidizing bacteria are directly consumed and assimilated by the fish Poecilia mexicana in a sulfide-rich cave stream in Tabasco state, Mexico. Our results provide evidence of a vertebrate deriving most of its organic carbon and nitrogen from in situ chemoautotrophic production, and reveals the importance of alternative energy production sources supporting animals in extreme environments.  相似文献   
157.
The populations of many native species have increased or expanded in distribution in recent decades, sometimes with negative consequences to sympatric native species that are rarer or less adaptable to anthropogenic changes to the environment. An example of this phenomenon from the Pacific Northwest is predation by locally abundant pinnipeds (seals and sea lions) on threatened, endangered, or otherwise depleted salmonid (Oncorhynchus spp.) populations. We used survey sampling methodology, acoustic telemetry, and molecular genetics to quantify the amount of harbor seal (Phoca vitulina) predation on a depressed run of coho salmon (O. kisutch) and to determine whether some seals consumed a disproportionately higher number of salmonids than others. Based on a probability sample totaling 759.5 h of observation, we estimated that seals consumed 1161 adult salmonids (95% CI = 503-1818 salmonids) during daylight hours over an 18.9-km estuarine study area in Oregon during an 84-d period in fall 2002. Simultaneous tracking of 56 seals via an acoustic telemetry array indicated that a small proportion of marked seals (12.5%) exhibited behavior that was consistent with specialization on salmonids. These seals spent the majority of their time in the riverine portion of the study area and did so disproportionately more at night than day. Genetic analysis of 116 salmonid structures recovered from 11 seal fecal samples suggested that coho salmon accounted for approximately one-half of total salmonid consumption. Though subject to considerable uncertainty, the combined results lead us to infer that seals consumed 21% (range = 3-63%) of the estimated prespawning population of coho salmon. We speculate that the majority of the predation occurred upriver, at night, and was done by a relatively small proportion of the local seal population. Understanding the extent and nature of pinniped predation can provide important inputs into risk assessments and other modeling efforts designed to aid the conservation and recovery of salmonids in the Pacific Northwest. Such understanding may also help inform management actions designed to reduce the impact of pinniped predation on salmonids, which potentially range from short-term lethal removal programs to long-term ecosystem restoration and protection efforts.  相似文献   
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Understanding the environmental contributors to population structure is of paramount importance for conservation in urbanized environments. We used spatially explicit models to determine genetic population structure under current and future environmental conditions across a highly fragmented, human‐dominated environment in Southern California to assess the effects of natural ecological variation and urbanization. We focused on 7 common species with diverse habitat requirements, home‐range sizes, and dispersal abilities. We quantified the relative roles of potential barriers, including natural environmental characteristics and an anthropogenic barrier created by a major highway, in shaping genetic variation. The ability to predict genetic variation in our models differed among species: 11–81% of intraspecific genetic variation was explained by environmental variables. Although an anthropogenically induced barrier (a major highway) severely restricted gene flow and movement at broad scales for some species, genetic variation seemed to be primarily driven by natural environmental heterogeneity at a local level. Our results show how assessing environmentally associated variation for multiple species under current and future climate conditions can help identify priority regions for maximizing population persistence under environmental change in urbanized regions.  相似文献   
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