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141.
We investigated the effect of different levels of hypercapnia-induced acidification (pH = 7.96, 7.31, 6.74 and 6.05) on the extracellular acid base balance of a shallow-water crustacean, the velvet swimming crab Necora puber over a period of 16 days. Any extracellular acidosis incurred was completely compensated by an increase in bicarbonate. Bicarbonate was partly, but not wholly, supplied by dissolution of the exoskeleton. This compensation was sustained for 16 days under all experimental treatments with two exceptions. First there was some evidence of extracellular acidosis in crabs after 16 days at pH = 6.74. Second at the lowest environmental pH (6.05) there was a marked uncompensated acidosis after 24 h. Necora puber appears less sensitive to low pH than many other species examined acutely. However, local acidification as a result of ocean CO2 dispersal or leakage from geological sequestration is likely to compromise even this species.  相似文献   
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The UK Government has provided financial support to developing renewable technologies through the Non-fossil Fu el Obligation imposed on the regional electricity companies. Several hundred renewable energy schemes have come forward to be assessed for their environmental suitability by local level regulators in a very poorly developed national policy framework. This study examines the development control decisions on windfarm applications since 1983 by the largest district council in Wales, and seeks to highlight the role played by clusters of public and private organizations in policy and programme implementation. With the multiple and sometimes conflicting objectives advanced by these organizations, it was in the interests of the district council to strike a negotiated consen sus between landscape conservation and inward investment concerns. The case study shows the crucial importan ce of the socio-political context for understanding the dynamics of policy making.  相似文献   
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Nervous system active pharmaceutical ingredients (APIs), including anti-depressants and opioids, are important clinically administered pharmaceuticals within healthcare facilities. This study provides source characterization data describing the composition and magnitude of nervous system APIs present in healthcare facility wastewaters. Concentrations and mass loadings of ten nervous system APIs and three nervous system API metabolites are reported for wastewaters from a hospital, nursing, assisted living, and independent living facility within a single municipality. Concentrations of nervous system APIs ranged from non-detectable levels for alprazolam in all four facility wastewaters to a high of 290 ng/L amitriptyline in nursing facility wastewater. The summed mean concentration of all thirteen analytes ranged from 402 ng/L in independent living facility wastewater to 624 ng/L in assisted living facility wastewater. Wastewater flow rates from each facility were combined with concentration data to estimate the daily mass loading of nervous system APIs leaving each facility through wastewater discharge to the municipal sewer system. The total mass loading of all thirteen analytes for the hospital, nursing, assisted living, and independent living facility was 228, 44, 29.5, and 28.1 mg/day, respectively. The total mass loading of nervous system APIs contributed to the municipality's wastewater from all four facilities was 330 mg/day.  相似文献   
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Environmental Science and Pollution Research - The energy potential of high-organic loaded agro-industrial effluents receiving biological treatment is often neglected, particularly in emergent...  相似文献   
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A 3-year monitoring of dissolved and particulate carbohydrate concentrations in four transects located in the Adriatic and Tyrrhenian Seas was performed in order to get information on the role played by carbohydrates in the mucilage formation in these areas. The application of time series analysis pointed out that the concentration of dissolved carbohydrates does not vary significantly in coincidence of the mucilage appearance showing an almost constant state with respect to time. In contrast, wider temporal variations of carbohydrate amounts, either increase or decrease, were observed when mucilages were lacking or reduced. This almost constant state of carbohydrate amounts observed in presence of mucilages that we define 'steady state' could be associated to an alteration of the complex chemical equilibrium between synthesis and degradation (either hydrolysis or oxidation) reactions of the organic polymers which are typical of the humification processes in the marine environment. The results of this study suggest that the monitoring of carbohydrates can represent an useful tool for the comprehension of the most relevant phenomena of mucilage appearance in the Northern Adriatic Sea.  相似文献   
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Children with a genetic absence of transcobalarnin 2 (TC2) are clinically asymptomatic at birth but develop severe megaloblastic anemia early in life. We have examined the incorporation of [57Co]-CN-B12 in the absence of any exogenous source of TC2 in control amniotic fluid derived cells and cultured diploid fibroblasts, and in fibroblasts from a patient with TC2 deficiency. Both control fibroblasts and arnniocytes incorporated labelled B12, into TC2-B12, and the proportion of labelled TC2-B12 could be increased by growing cells in the presence of chloroquine which prevents intralysosomal hydrolysis of the TC2-B12 complex. In contrast, fibroblasts from the patient with TC2 deficiency incorporated almost no label as TC2-B12. These studies suggest that TC2 deficiency either due to aberrant production of TC2 or because of the production of an abnormal TC2 which does not bind B12 can be diagnosed before birth.  相似文献   
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Contamination of aquatic systems mainly by urbanization and poor sanitation, deficient or lack of wastewater treatments, dumping of solid residues, and run off has led to the presence of particles, including manmade polymers, in tissues of many marine and freshwater species. In this study, the prevalence of microplastics (MPs) in freshwater fish from farmed and natural sources was investigated. Oreochromis niloticus from aquaculture farms in the Huila region in Colombia, and two local species (Prochilodus magdalenae and Pimelodus grosskopfii), naturally present in surface waters were sampled. Of the particles identified, fragments were the predominant type in the three tissue types (stomach, gill, and flesh) derived from farmed and natural fishes. MicroFT-IR spectroscopy was conducted on 208 randomly selected samples, with 22% of particles identified as MPs based on spectra with a match rate ≥ 70%. A total of 53% of identified particles corresponded to cellophane/cellulose, the most abundant particle found in all fish. Not all fish contained MPs: 44% of Oreochromis farmed fish contained MPs, while 75% of natural source fish contained MPs in any of its tissues. Overall, polyethylene terephthalate (PET), polyester (PES), and polyethylene (PE) were the prevalent MPs found in the freshwater fish. A broader variety of polymer types was observed in farmed fish. The edible flesh part of fish presented the lower prevalence of MPs compared to gill and stomach (gut), with gut displaying a higher frequency and diversity of MPs. This preliminary study suggests that the incidence and type of MPs varies in farmed verses natural fish sources as well as across different tissue types, with significantly less detected within the edible flesh tissues compared with stomach and gill tissues.

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