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121.
Environmental Science and Pollution Research - Clean water production using green energy supply plays a significant role in the globe’s health and economic development. In recent years, so...  相似文献   
122.
Environment Systems and Decisions - Early warning systems for weather events are becoming widespread as technological capacities develop. For warnings to be effective, they must allow enough lead...  相似文献   
123.
Amyotrophic lateral sclerosis (ALS), a progressive disorder that usually runs a fatal course within 2–5 years of onset, is characterized by loss of motor neurons in the cortex, brain stem, and spinal cord. In this study mercury (Hg) concentrations were determined in blood samples of 40 ALS patients, of whom 24 ALS patients were from the Ganga plain region and their metal levels were found to be significantly higher. In contrast, Hg levels in the 16 ALS patients from non-Ganga plain regions whose levels were similar to those of the control subjects. Mercury in stream water samples and freshly deposited stream sediment were determined in the locations of patients’ native residences along the Ganga plain region and metal levels were found to be higher than the threshold guideline values for Hg in stream waters recommended by WHO. The geo-accumulation index in selected sites of freshly deposited stream sediment ranged from moderate to highly polluted. The high levels of Hg observed in ALS patients may potentially alter the redox status of neuronal cell components and induce cell-death pathways.  相似文献   
124.
Data from National Health and Nutrition Examination Survey for children aged 6–11 years for 1999–2014 were used to study time trends and factors affecting the urinary levels of barium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten. Adjusted levels in urine declined every two years by 5.9% for barium, by 1.2% for cesium, by 18.2% for lead, and by 14% for antimony. For every additional smoker smoking inside a home, the levels of barium increased by 10.6% and for lead by 10%, but for tungsten levels decreased by 7.7%.  相似文献   
125.
Over 350 European Integrated Coastal Zone Management (ICZM) ‘best practice’ case studies are documented in the OURCOAST online public database, to ensure that lessons learned from experiences and practices are shared and improve coastal management practices. However, concrete criteria for ‘best practice’ are missing and a critical evaluation of the success of these case studies did not take place. We present an indicator-based tool and methodology that allows assessing the progress towards sustainability of ICZM measures. An indicator-based tool was applied to 18 thematically different coastal case studies using two different methods: a fast screening and an analysis in-depth assessment. Both methods used help to identify strengths and weaknesses of ICZM and their contribution to sustainable development. However, indicator scores were highly affected by evaluators’ background and perception. The tool is user-friendly and easy to apply, it indicates what progress has made towards sustainability and to which extent targets have been met.  相似文献   
126.
Many breeding seabird species are central-place foragers and constrained to find productive prey patches within their foraging ranges. We assessed how different populations of a pelagic seabird species, the Cory’s shearwater Calonectris diomedea, breeding in oceanic and neritic conditions, cope with these constraints in the North Atlantic, during both incubation and chick-rearing periods. We analysed 237 foraging trips to study the movements and oceanographic characteristics of foraging habitats of seven different populations of Cory’s shearwaters. Generally, oceanic populations exhibited higher foraging effort, by travelling more time and to more distant areas, and larger home ranges and feeding areas, than the neritic population (i.e. breeding on an island within the Portuguese continental platform). On their short trips (i.e. ≤4 days), birds from the different populations fed mostly in shallower waters around the colony. During long trips (i.e. ≥5 days), feeding areas of both oceanic and neritic populations were characterized by high concentration values of chlorophyll-a, low sea-surface temperature and shallower habitats, with oceanic populations of the Azores exploiting areas north of the islands over known seamounts and frontal regions. Birds from other oceanic population (Selvagens) also exploited the African continental shelf system on their long trips. The home ranges of the different populations overlapped widely, but there was a general spatial segregation in terms of the core feeding areas at the population level. Core feeding areas and areas of foraging overlap between different populations should be important to inform conservation management measures, such as the definition of Marine Important Bird Areas for seabirds over the North Atlantic.  相似文献   
127.
Aranked set sample (RSS), if not balanced, is simply a sample of independent order statistics gener- ated from the same underlying distribution F. Kvam and Samaniego (1994) derived maximum likelihood estimates of F for a general RSS. In many applications, including some in the environ- mental sciences, prior information about F is available to supplement the data-based inference. In such cases, Bayes estimators should be considered for improved estimation. Bayes estimation (using the squared error loss function) of the unknown distribution function F is investigated with such samples. Additionally, the Bayes generalized maximum likelihood estimator (GMLE) is derived. An iterative scheme based on the EM Algorithm is used to produce the GMLE of F. For the case of squared error loss, simple solutions are uncommon, and a procedure to find the solution to the Bayes estimate using the Gibbs sampler is illustrated. The methods are illustrated with data from the Natural Environmental Research Council of Great Britain (1975), representing water discharge of floods on the Nidd River in Yorkshire, England  相似文献   
128.
Environmental Chemistry Letters - Global pollution is calling for advanced methods to remove contaminants from water and wastewater, such as TiO2-assisted photocatalysis.  The...  相似文献   
129.
130.
The ability to detect 'known' differences in urinary analyte concentrations due to gender, age, and race/ethnicity when adjusted for similar differences in urinary creatinine concentrations were evaluated by a single-stage and a two-stage model by ten simulation studies. Log10 transformed values of observed urinary analyte concentration were used as the dependent variable and age, gender, and race/ethnicity were used as the categorical independent variables. In addition, while single-stage model used log10 transformed values of urinary creatinine as a covariate, two-stage model used a correction factor (CF) determined during the first stage of the model by fitting a secondary model for urinary creatinine. Single-stage model was almost always able to statistically significantly detect 'known' differences due to age, gender, and race/ethnicity. On the other hand, two-stage model was able to statistically significantly detect 'known' differences due to age, gender, and race/ethnicity a maximum of 87.2% of the times and as low as 10.6% of the times primarily because of the presence of multicollinearity between CF and urinary creatinine concentrations. Consequently, as long as the sole objective is to estimate the urinary analyte concentrations adjusted for the effect of all factors including urinary creatinine, single-stage models are the models of choice.  相似文献   
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