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321.
Since the rates and causes of mortality are critical indicators of the overall health of a population, it is important to evaluate mortality even where no complete vital statistics reporting exists. Such settings include humanitarian emergencies. Experience in cross-sectional survey methods to assess retrospectively crude, age-specific, and maternal mortality in stable settings has been gained over the past 40 years, and methods appropriate to humanitarian emergencies have been developed. In humanitarian emergencies, crude and age-specific mortality can be gauged using methods based on the enumeration of individuals resident in randomly selected households—frequently referred to as a household census. Under-five mortality can also be assessed through a modified prior birth history method in which a representative sample of reproductive-aged women are questioned about dates of child births and deaths. Maternal mortality can be appraised via the initial identification of maternal deaths in the study population and a subsequent investigation to determine the cause of each death.  相似文献   
322.
Environmental quality strongly depends on human behaviour patterns. We review the contribution and the potential of environmental psychology for understanding and promoting pro-environmental behaviour. A general framework is proposed, comprising: (1) identification of the behaviour to be changed, (2) examination of the main factors underlying this behaviour, (3) design and application of interventions to change behaviour to reduce environmental impact, and (4) evaluation of the effects of interventions. We discuss how environmental psychologists empirically studied these four topics, identify apparent shortcomings so far, and indicate major issues for future research.  相似文献   
323.
An urban community PM10 (particulate matter < or = 10 microm in aerodynamic diameter) air pollution study was conducted in Paterson, NJ, a mixed land-use community that is interspersed with industrial, commercial, mobile, and residential land-use types. This paper examines (1) the spatial/temporal variation of PM10, elemental carbon (EC), organic carbon (OC), and nine elements; and (2) the impact of land-use type on those variations. Air samples were collected from three community-oriented locations in Paterson that attempted to capture industrial, commercial, and mobile source-dominated emissions. Sampling was conducted for 24 hr every 6 days from November 2005 through December 2006. Samples were concurrently collected at the New Jersey Department of Environmental Protection-designated air toxics background site in Chester, NJ. PM10 mass, EC, OC, and nine elements (Ca, Cu, Fe, Pb, Mn, Ni, S, Ti, and Zn) that had more than 50% of samples above detection and known sources or are toxic were selected for spatial/temporal analysis in this study. The concentrations of PM10, EC, OC, and eight elements (except S) were significantly higher in Paterson than in Chester (P < 0.05). The concentrations of these elements measured in Paterson were also found to be higher during winter than the other three seasons (except S), and higher on weekdays than on weekends (except Pb). The concentrations of EC, Cu, Fe, and Zn at the commercial site in Paterson were significantly higher than the industrial and mobile sites; however, the other eight species were not significantly different within the city (P > 0.05). These results indicated that anthropogenic sources of air pollution were present in Paterson. The source apportionment confirmed the impact of vehicular and industrial emissions on the PM10 ambient air pollution in Paterson. The multiple linear regression analysis showed that categorical land-use type was a significant predictor for all air pollution levels, explaining up to 42% of the variability in concentration by land-use type only.  相似文献   
324.
Exposure to ambient polycyclic aromatic hydrocarbons (PAHs) is a potential health concern for communities because many PAHs are known to be mutagenic and carcinogenic. However, information on ambient concentrations of PAHs in communities is very limited. During the Urban Community Air Toxics Monitoring Project, Paterson City, NJ, PAH concentrations in ambient air PM10 (particulate matter < or = 10 microm in aerodynamic diameter) were measured from November 2005 through December 2006 in Paterson, a mixed-use urban community located in Passaic County, NJ. Three locations dominated by industrial, commercial, and mobile sources were chosen as monitoring sites. The comparison background site was located in Chester, NJ, which is approximately 58 km west/southwest of Paterson. The concentrations of all of the individual PAHs at all three Paterson sites were found to be significantly higher than those at the background site (P < 0.05). The PAH profiles obtained from the three sites with different land-use patterns showed that the contributions of heavier PAHs (molecular weight > 202) to the total PAHs were significantly higher at the industrial site than those at the commercial and mobile sites. Analysis of the diagnostic ratios between PAH isomers suggested that the diesel-powered vehicles were the major PAH sources in the Paterson area throughout the year. The operation of industrial facilities and other combustion sources also partially contributed to PAH air pollution in Paterson. The correlation of individual PAH, total PAH, and the correlation of total PAHs with other air co-pollutants (copper, iron, manganese, lead, zinc, elemental carbon, and organic carbon) within and between the sampling sites supported the conclusions obtained from the diagnostic ratio analysis.  相似文献   
325.
The aim of the present study was to understand the placental transfer of polychlorinated biphenyls (PCBs), specific hydroxylated PCB metabolites (OH-PCBs), and pentachlorophenol (PCP) in blood serum, in a birth cohort from eastern Slovakia. During the period 2002-2004, cord blood specimens were collected in parallel with maternal specimens from women delivering in the two eastern Slovak districts of Michalovce and Svidnik/Stropkov. A total of 92 pairs of mother-cord specimens at delivery were selected for this study. 4-OH-CB107, 3-OH-CB153, 4-OH-CB146, 3'-OH-CB138, 4-OH-CB187, and 4'-OH-CB172 were quantified. The median concentrations of Sigma(17)PCBs, Sigma(6)OH-PCBs, and PCP in cord serum were 0.92, 0.33, and 0.69 ng/g wet wt., respectively and highly correlated with the corresponding maternal serum levels (correlations were R(2)=0.61, 0.78, and 0.82, respectively). The median cord to mother ratios of the Sigma(17)PCBs, Sigma(6)OH-PCBs, and PCP were 0.18, 0.75, and 1.10, respectively. The median ratio of the Sigma(6)OH-PCBs to the Sigma(17) PCBs in the cord serum was 0.38 from wet weight based concentrations, which was about four times higher than the ratio of these compounds in maternal serum (0.09). PCP was more abundant than any PCB or OH-PCB congener measured in cord serum. The higher cord to maternal ratios of OH-PCB metabolites as compared with the parent compounds suggests either a higher placental transfer rate or greater metabolism in the fetus as compared with the maternal compartment. These findings are consistent with their preferential binding to TTR that can cross the placenta. The cord to maternal ratio varies by congener (e.g., 4-OH-CB107=0.58, 4-OH-CB146=0.74, 3'-OH-CB138=1.01).  相似文献   
326.
一株毒死蜱降解菌的分离鉴定及降解性能研究   总被引:4,自引:0,他引:4  
从农药厂废水处理池污泥中分离到一株对毒死蜱有较强降解能力的菌株CH3,通过生理生化试验初步将该菌鉴定为哈夫尼菌属(Hafnia sp.)。CH3能以毒死蜱为唯一碳源生长,在温度为30℃,pH为7.0,毒死蜱初始浓度为200 mg/L的条件下,历时6 d,毒死蜱的降解率可达78.5%。菌株最适生长温度为37℃,最适pH值为7.0,最适降解浓度为200 mg/L。对碳、氮源利用广泛,最佳碳源为蔗糖和葡萄糖,对氮源选择性不高,在无机氮源和有机氮源中均能较好地生长。  相似文献   
327.
Better insight in the possible range of future N?O emissions can help to construct mitigation and adaptation strategies and to adapt land use planning and management to climate objectives. The Dutch fen meadow landscape is a hotspot of N?O emission due to high nitrogen inputs combined with moist peat soils due to land use change. Socio-economic developments in the area are expected to have major impacts on N?O emission. The goals of this study are to estimate changes in N?O emissions for the period 2006-2040 under three different scenarios for the Dutch fen meadow landscape (rural production, rural fragmentation, and rural multifunctionality) and to quantify the share of different emission sources. Three scenarios were constructed and quantified based on the Story-And-Simulation approach. The rural production and the rural fragmentation scenarios are characterized by globalization and a market-oriented economy; in the rural production scenario dairy farming has a strong competitive position in the study region, while under the rural fragmentation scenario agriculture is declining. Under the rural multifunctionality scenario, the global context is characterized by regionalization and stronger regulation toward environmental issues. The N?O emission decreased between 2006 and 2040 under all scenarios. Under the rural production scenario, the N?O emission decreased by 7%. Due to measures to limit peat mineralization and policies to reduce agricultural emissions, the rural multifunctionality scenario showed the largest decrease in N?O emissions (44%). Under the rural fragmentation scenario, in which the dairy farming sector is diminished, the emission decreased by 33%. Compared to other uncertainties involved in N?O emission estimates, the uncertainty due to possible future land use change is relatively large and assuming a constant emission with time is therefore not appropriate.  相似文献   
328.
Abstract

Hazardous waste sites and industrial facilities contain area sources of fugitive emissions. Emission rate measurements or estimates are necessary for air pathway assessments for these sources. Emission rate data can be useful for the design of emission control and remediation strategies as well as for predictive modeling for population exposure assessments. This paper describes the use of a direct emission measurement approach – the enclosure approach using an emission isolation flux chamber – to measure emission rates of various volatile organic compounds (VOCs) from contaminated soil and water. A variety of flux chamber equipment designs and operating procedures have been employed by various researchers. This paper contains a review of the design and operational variables that affect the accuracy and precision of the method. Guidance is given as to the optimum flux chamber design and operating conditions for various types of emission sources. Also presented is a generic quality control program that gives the minimum number of duplicate, blank, background, and repeat samples that should be performed.  相似文献   
329.
Harmful or nuisance algal blooms can cause economic damage to fisheries and tourism. Additionally, toxins produced by harmful algae and ingested via contaminated shellfish can be potentially fatal to humans. The seas around the Orkney Islands, UK currently hold a number of toxic algal species which cause shellfishery closures in most years. Extensive and costly monitoring programs are carried out to detect harmful microalgae before they reach action levels. However, the ability to distinguish between toxic and non-toxic strains of some algae is not possible using these methods. The microarrays for the detection of toxic algae (MIDTAL) microarray contains rRNA probes for toxic algal species/strains which have been adapted and optimized for microarray use. In order to investigate the use of the chip for monitoring in the Orkney Islands, samples were collected between 2009 and 2011 from Brings Deep, Scapa Flow, Orkney Islands, UK; RNA was extracted and hybridized with generation 2 and 3.1 of the chip. The data were then compared to cell counts performed under light microscopy and in the case of Alexandrium tamarense to qPCR data targeting the saxitoxin gene and the LSU-rRNA gene. A good agreement between cell numbers and microarray signal was found for A. tamarense, Pseudo-nitzschia sp., Dinophysis sp. (r?<?0.5, for all) in addition to this there the chip successfully detected a large bloom of Karenia mikimotoi (r?<?0.70) in August and September 2011. Overall, there was good improvement in probe signal between generation 2 and generation 3.1 of the chip with much less variability and more consistent results and better correlation between the probes. The chip performed well for A. tamarense group I signal to cell numbers in calibrations (r?>?0.9). However, in field samples, this correlation was slightly lower suggesting interactions between all species in the sample may affect signal. Overall, the chip showed it could identify the presence of target species in field samples although some work is needed to improve the quantitative nature of the chip before it would be suitable for monitoring in the Orkney Islands.  相似文献   
330.
Dinophysis and Phalacroma species containing diarrheic shellfish toxins and pectenotoxins occur in coastal temperate waters all year round and prevent the harvesting of mussels during several months each year in regions in Europe, Chile, Japan, and New Zealand. Toxicity varies among morphologically similar species, and a precise identification is needed for early warning systems. Molecular techniques using ribosomal DNA sequences offer a means to identify and detect precisely the potentially toxic species. We designed molecular probes targeting the 18S rDNA at the family and genus levels for Dinophysis and Phalacroma and at the species level for Dinophysis acuminata, Dinophysis acuta, and Dinophysis norvegica, the most commonly occurring, potentially toxic species of these genera in Western European waters. Dot blot hybridizations with polymerase chain reaction (PCR)-amplified rDNA from 17 microalgae were used to demonstrate probe specificity. The probes were modified along with other published fluorescence in situ hybridization and PCR probes and tested for a microarray platform within the MIDTAL project (http://www.midtal.com). The microarray was applied to field samples from Norway and Spain and compared to microscopic cell counts. These probes may be useful for early warning systems and monitoring and can also be used in population dynamic studies to distinguish species and life cycle stages, such as cysts, and their distribution in time and space.  相似文献   
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