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191.
This paper explores the application of the fuzzy logic for risk assessment of major hazards connected with transportation of flammable substances in long pipelines. As a basis for risk assessment, the framework of the fuzzy Layer of Protection Analysis (fLOPA) was used. fLOPA presents a new approach to risk assessment based on two assumptions: 1. different effects of the layer of protection functions on particular elements of the risks (frequency and severity of consequence), and 2. the application of fuzzy logic system (FLS) composed of three elements: fuzzification, inference process and defuzzification. A further calculation follows LOPA methodology with the use of fuzzy logic system where fuzzy risk matrix is used for risk assessment. A typical case study comprising section of a long pipeline failure is performed and a comparison between the classical LOPA approach and fuzzy approach is made.  相似文献   
192.
Microcystins (MCYSTs) are toxins produced by cyanobacteria in aquatic environment and are of high potential risk to aquatic organisms. The physiological responses and pathobiological developments that they elicit in fish have been extensively studied, mainly through acute toxicity experiments. This study was designed to examine the seasonal fluctuation of biochemical markers of oxidative stress in different tissues of a natural population of Cyprinus carpio inhabiting a shallow Mediterranean lake, along with the respective MCYSTs concentrations in blood and tissues at environmentally relevant MCYSTs values. MCYSTs content was assessed in liver, kidney, intestine, brain and muscle along with the MCYSTs in lake water and scum applying ELISA technique. Catalase activity, GSH/GSSH relative concentrations and lipid peroxidation were used as biochemical markers. Our results suggest that common carp of Lake Pamvotis exposed to naturally fluctuating concentrations of MCYST in water and scum contained stably high MCYST concentrations in all tissues that might pose a threat to public health. Liver and kidney were the primary target organs. Tissue concentrations did not correlate with the response of any of the elements of the antioxidant defence system. Hepatic catalase, GSH content and TBARS in all tissues tested followed the fluctuations of major limnological parameters, i.e. water temperature and oxygen concentration, chlorophyll-a, MCYST in water and scum, suggesting that they should be cautiously used to monitor exposure to MCYSTS in natural freshwater ecosystems.  相似文献   
193.
The Conservation Reserve Program (CRP) has converted just over 36 million acres of cropland into potential wildlife habitat, primarily grassland. Thus, the CRP should benefit grassland songbirds, a group of species that is declining across the United States and is of conservation concern. Additionally, the CRP is an important part of multi-agency, regional efforts to restore northern bobwhite populations. However, comprehensive assessments of the wildlife benefits of CRP at regional scales are lacking. We used Breeding Bird Survey and National Resources Inventory data to assess the potential for the CRP to benefit northern bobwhite and other grassland birds with overlapping ranges and similar habitat associations. We built regression models for 15 species in seven different ecological regions. Forty-nine of 108 total models contained significant CRP effects (P < 0.05), and 48 of the 49 contained positive effects. Responses to CRP varied across ecological regions. Only eastern meadowlark was positively-related to CRP in all the ecological regions, and western meadowlark was the only species never related to CRP. CRP was a strong predictor of bird abundance compared to other land cover types. The potential for CRP habitat as a regional conservation tool to benefit declining grassland bird populations should continue to be assessed at a variety of spatial scales. We caution that bird-CRP relations varied from region to region and among species. Because the NRI provides relatively coarse resolution information on CRP, more detailed information about CRP habitats (spatial arrangement, age of the habitat (time since planting), specific conservation practices used) should be included in future assessments to fully understand where and to what extent CRP can benefit grassland birds.  相似文献   
194.
Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO2, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h?1. The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors’ concentrations were found to be compared well with the experimentally measured values.  相似文献   
195.
The U.S. Environmental Protection Agency estimates that residential radon levels in the United States lead to approximately 13,600 lung cancer deaths per year. To address this problem, the Agency has identified three program initiatives that can provide substantial reductions in the public’s risks: (1) public information activities that urge the public to test for radon and reduce elevated concentrations in existing homes, (2) new construction standards to reduce radon entry, and (3) radon testing and mitigation during real estate transactions. This paper analyzes the costs and risk reductions that could result from the implementation of these major initiatives, showing how all three elements cost-effectively protect the public’s health.  相似文献   
196.
Objective: Rapid urbanization and motorization without corresponding increases in helmet usage have made traumatic brain injury due to road traffic accidents a major public health crisis in Cambodia. This analysis was conducted to quantify the impact of helmets on severity of injury, neurosurgical indication, and functional outcomes at discharge for motorcycle operators who required hospitalization for a traumatic brain injury following a road traffic accident in Cambodia.

Methods: The medical records of 491 motorcycle operators who presented to a major tertiary care center in Cambodia with traumatic brain injury were retrospectively analyzed using multivariate logistic regression.

Results: The most common injuries at presentation were contusions (47.0%), epidural hematomas (30.1%), subdural hematomas (27.9%), subarachnoid hemorrhages (12.4%), skull fractures (21.4%), and facial fractures (18.5%). Moderate-to-severe loss of consciousness was present in 36.3% of patients. Not wearing a helmet was associated with an odds ratio of 2.20 (95% confidence interval [CI], 1.15–4.22) for presenting with moderate to severe loss of consciousness compared to helmeted patients. Craniotomy or craniectomy was indicated for evacuation of hematoma in 20.0% of cases, and nonhelmeted patients had 3.21-fold higher odds of requiring neurosurgical intervention (95% CI, 1.25–8.27). Furthermore, lack of helmet usage was associated with 2.72-fold higher odds of discharge with functional deficits (95% CI, 1.14–6.49). In total, 30.1% of patients were discharged with severe functional deficits.

Conclusions: Helmets demonstrate a protective effect and may be an effective public health intervention to significantly reduce the burden of traumatic brain injury in Cambodia and other developing countries with increasing rates of motorization across the world.  相似文献   

197.
An efficient program for assessing groundwater extraction system capture zones has been developed that can be run on any digitized potentiometric surface. The program was developed in response to the need to simulate particle capture by multiple remediation system elements (i.e., extraction wells, hydraulic barrier, etc.) at a hydrogeologically complex site in California (the Site). The method uses MODPATH software but does not otherwise require a groundwater model. The program called “CapZone FileBuilder” (Capture Zone File Builder) Version 1.0 was created to import digitized potentiometric surfaces and use them to create MODFLOW output files (using native USGS MODFLOW‐2005 codes). CapZone FileBuilder was created using the C# programming language with Visual Studio 2013 as the integrated development environment. The model was applied to a site that has a regulatory requirement for capture analysis as part of an annual remedy‐effectiveness evaluation for groundwater contamination. Previously, capture analysis was highly labor intensive and time consuming, performed using manual flow net analysis or calibration of highly discretized MODFLOW groundwater models. CapZone FileBuilder is now used to perform the capture analysis for this site and is universally applicable to any site with a groundwater potentiometric map. ©2017 Wiley Periodicals, Inc.  相似文献   
198.
Anurans (frogs and toads) are among the most globally threatened taxonomic groups. Successful conservation of anurans will rely on improved data on the status and changes in local populations, particularly for rare and threatened species. Automated sensors, such as acoustic recorders, have the potential to provide such data by massively increasing the spatial and temporal scale of population sampling efforts. Analyzing such data sets will require robust and efficient tools that can automatically identify the presence of a species in audio recordings. Like bats and birds, many anuran species produce distinct vocalizations that can be captured by autonomous acoustic recorders and represent excellent candidates for automated recognition. However, in contrast to birds and bats, effective automated acoustic recognition tools for anurans are not yet widely available. An effective automated call-recognition method for anurans must be robust to the challenges of real-world field data and should not require extensive labeled data sets. We devised a vocalization identification tool that classifies anuran vocalizations in audio recordings based on their periodic structure: the repeat interval-based bioacoustic identification tool (RIBBIT). We applied RIBBIT to field recordings to study the boreal chorus frog (Pseudacris maculata) of temperate North American grasslands and the critically endangered variable harlequin frog (Atelopus varius) of tropical Central American rainforests. The tool accurately identified boreal chorus frogs, even when they vocalized in heavily overlapping choruses and identified variable harlequin frog vocalizations at a field site where it had been very rarely encountered in visual surveys. Using a few simple parameters, RIBBIT can detect any vocalization with a periodic structure, including those of many anurans, insects, birds, and mammals. We provide open-source implementations of RIBBIT in Python and R to support its use for other taxa and communities.  相似文献   
199.
Human exposure to polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) was evaluated in Ghana using breast milk samples collected in 2004 and 2009. Mean levels and ranges of PBDEs (4.5; 0.86-18 ng/g lw) and PCBs (62; 15-160 ng/g lw) observed in the present study were unexpectedly high, in spite of the fact that Ghana is a non-industrialized country when compared with many of the Asian and European countries. Significant increases were found in the concentrations of PCBs and PBDEs over the years, while no significant increase was observed for HBCDs. Estimated hazard quotient (HQ) showed that all the mothers had HQ values exceeding the threshold of 1 for PCBs, indicating potential health risk for their children. PCBs in dirty oils and obsolete equipment should be of concern as potential sources in Ghana, and e-waste recycling with little or no experience in safe handling could be a threat to this sub-region noted for unregulated disposal of e-waste. The results may point towards an increase in trends in human milk in Ghana, especially in the larger cities but further analysis would be required to confirm this upward trend in levels. This is the first study to report BFRs in human breast milk from Africa, and undoubtedly from Ghana.  相似文献   
200.
In the present study, an investigation of the mineralogy and morphology, the heavy metal content and the health risk of urban road dusts from the second largest city of Greece was conducted. For this reason road dust samples from selected sites within the city core area were collected. No differences were observed in the mineralogy of road dusts coming from different sampling sites, and they were mainly consisted of quartz and calcite, while an elevated amorphous content was detected. Morphologically road dusts presented Ca-rich, Fe-rich and silicates particles with various shapes and sizes. The mean concentrations of Cd, Cr, Cu, Mn, Ni, Pb and Zn in road dust were 1.76, 104.9, 662.3, 336.4, 89.43, 209 and 452.8 μg g?1, respectively. A series of spatial distribution patterns revealed that the hotspot areas were tended to associate with major road junctions and regions with high traffic. Combination of pollution indexes and statistical analyses (correlation analysis, cluster analysis and principal component analysis) revealed that road dusts have a severe influence by anthropogenic activities. In attempt to identify the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Cr, Cu, Fe and Zn mainly originated from tire/break wear and vehicle abrasions, while Cd, Mn and Pb were mainly related to fuel/oil leakage from automobiles along with oil lubricants and vehicle abrasion. Hazard quotient values for children based on total metal concentrations for the road dust ingestion route were lower than safe level (=1). However, the fact that the Hazard Index value for Pb (0.459) which is a particularly toxic metal, was close to safe level, renders essential further investigation in order to provide more reliable characterizations of potential health risks.  相似文献   
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