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561.
Regional Environmental Change - Global climate models predict temperature rises and changes in precipitation regimes that will shift regional climate zones and influence the viability of...  相似文献   
562.
Interactions between humans and wildlife resulting in negative impacts are among the most pressing conservation challenges globally. In regions of smallholder livestock and crop production, interactions with wildlife can compromise human well-being and motivate negative sentiment and retaliation toward wildlife, undermining conservation goals. Although impacts may be unavoidable when human and wildlife land use overlap, scant large-scale human data exist quantifying the direct costs of wildlife to livelihoods. In a landscape of global importance for wildlife conservation in southern Africa, we quantified costs for people living with wildlife through a fundamental measure of human well-being, food security, and we tested whether existing livelihood strategies buffer certain households against crop depredation by wildlife, predominantly elephants. To do this, we estimated Bayesian multilevel statistical models based on multicounty household data (n = 711) and interpreted model results in the context of spatial data from participatory land-use mapping. Reported crop depredation by wildlife was widespread. Over half of the sample households were affected and household food security was reduced significantly (odds ratio 0.37 [0.22, 0.63]). The most food insecure households relied on gathered food sources and welfare programs. In the event of crop depredation by wildlife, these 2 livelihood sources buffered or reduced harmful effects of depredation. The presence of buffering strategies suggests a targeted compensation strategy could benefit the region's most vulnerable people. Such strategies should be combined with dynamic and spatially explicit land-use planning that may reduce the frequency of negative human–wildlife impacts. Quantifying and mitigating the human costs from wildlife are necessary steps in working toward human–wildlife coexistence.  相似文献   
563.
A sustainable return on investment (sROI) analysis is a quantitative approach that captures the economic, environmental, and social impacts of an investment strategy in monetary terms—today and into the future. By providing a broader accounting of the benefits and costs, sROI provides a framework for optimal decision making. sROI is a nonproprietary methodology based on economic principles and includes an uncertainty analysis to demonstrate the likelihood of realizing costs and benefits. This approach provides a more comprehensive picture of projects and supports the selection of investment strategies that are defensible and transparent. sROI can provide the framework and metrics for the evaluation and selection of remediation projects. A demonstration study of a DuPont remediation project illustrates the process and outcome of an sROI analysis. © 2014 Wiley Periodicals, Inc.  相似文献   
564.
We present reports of sightings of living and stranded specimens of Rhizostoma luteum on the Atlantic coast of Morocco and along the south shore of the Iberian Peninsula in June–July 2012 and in January–February 2013. During summer 2012 and following the dominant currents, the jellyfish first appeared in the Gulf of Cadiz west of the Strait of Gibraltar. Subsequently, seven additional sightings were reported east of the Strait, in the Alboran Sea. In winter 2013, another event of stranded individuals of this species occurred in the Gulf of Cadiz. A phylogenetic analysis performed on the mitochondrial cytochrome c oxidase I (COI) gene sequence in specimens from both stranding events confirmed the morphological classification, ratifying that R. luteum differs from Rhizostoma octopus and Rhizostoma pulmo. This study records the presence of this species for the first time in 60 years.  相似文献   
565.
Epidemiological studies have shown that there is a link between asthma and brain damage,but toxicological studies have not fully confirmed yet,especially the effects of asthma on the brain. In this study,at first,we explore the effects of asthma on the brain through the establishment of an allergic asthma model. Then PM_(2.5),a typical outdoor air pollutant and formaldehyde,a typical indoor air pollutant were selected to be closer to the true environment and find whether there is any synergism between them. In this study,an ovalbumin( OVA)-sensitized mice asthma model was established. 30 male Balb/c mice were randomly divided into 5 groups:( 1) saline control group,( 2) OVA-sensitized group,( 3) OVA-combined with formaldehyde exposure group,( 4) OVA-combined with PM_(2.5) exposure group,( 5) Combination of OVA,formaldehyde and PM_(2.5) exposure group. The mice were inhaled with formaldehyde or/and instilled with PM_(2.5) from day 1 to 18. The mice asthma model was developed by OVA sensitization and challenge. The mice were sensitized with OVA+Al( OH)3( 5 mg OVA and 175 mg Al( OH)3 in 30 m L saline each time) or saline( 30 m L saline each time) by intraperitoneal injection on day 1,7 and 14.This was then followed by an aerosol challenge in 1% OVA( 30 min·d~(-1)) from day 19 to 25( 7 times) using an ultrasonic nebulizer. On the 26 th day,the organ coefficient of mice brain was counted,then the contents of oxidative stress of mice brain were measured,including reactive oxygen species( ROS),glutathione( GSH) and malondialdehyde( MDA),and the concentrations of NF-κB and interleukin-1β( IL-1β) were detected by using ELISA kits.Detection of interleukin-6( IL-6) was made with immunohistochemical method. Histological assay for brain was also conducted. In our results,all the OVA treated groups showed a significant increase of ROS and a significant decrease of GSH contents when compared with the control group. Except OVA-sensitized group,other OVA treated groups also showed a significant increase of MDA contents when compared with the control group,and MDA contents of OVA-sensitized group showed significant change when compared to the combined exposure group. In ROS and GSH,combined exposure showed some joint effect compared with single exposure. When OVA was applied in combination with formaldehyde and PM_(2.5),NF-κB was activated. And all the OVA treated groups showed increased levels of IL-1β and IL-6 compared with the control group. And the combined exposure showed an aggravated effect when compared with OVA-sensitized group. Histopathological observation of the hippocampus in mice brain clearly showed the difference of eosin( EO) stained neurons in the combined exposure group compared with the control group and OVA-sensitized group. The pyramidal neurons of the mice with allergic asthma exposed to formaldehyde and/or PM_(2.5) had been reduced in number,the cells were swollen and the dendrites had disappeared. Allergic asthma can cause damage to the brain through oxidative stress. Exposure to formaldehyde and PM_(2.5) will increase the damage caused by allergic asthma to the brain,which may be mediated by oxidative stress and NF-κB activation.This promotes the release of the inflammatory factors,resulting in increased inflammation.  相似文献   
566.
The short term human exposure studies conducted on populations exposed to high concentrations of inorganic arsenic in soil have been inconsistent in demonstrating a relationship between environmental concentrations and exposure measures. In Australia there are many areas with very high arsenic concentrations in residential soil most typically associated with gold mining activities in rural areas. This study aimed to investigate the relationship between environmental arsenic and urinary inorganic arsenic concentrations in a population living in a gold mining area (soil arsenic concentrations between 9 and 9900 mg kg(-1)), and a control population with low arsenic levels in soil (between 1 and 80 mg kg(-1)). Risk factors for increased urinary arsenic concentrations were also explored. There was a weak but significant relationship between soil arsenic concentrations and inorganic urinary arsenic concentration with a Spearman correlation coefficient of 0.39. When participants with greater than 100 mg kg(-1) arsenic in residential soil were selected, the coefficient increased to 0.64. The geometric mean urinary inorganic arsenic concentration for the exposed group was 1.64 microg L(-1) (相似文献   
567.
Paramuricea clavata (Risso, 1826) and Eunicella singularis (Esper, 1794) are the most representative gorgonian species in hard bottoms sublittoral communities in the Western Mediterranean Sea. Reproductive cycles of two populations of both species were studied in two distinct locations approximately 600 km apart (Medes Islands and Cape of Palos), in order to assess interpopulation variability on a relevant geographic scale. Seasonal variation of lipid concentration levels in the gorgonian tissue was used as a tool to quantify energy storage by each studied population in order to explain possible interpopulation differences in gonadal output. Sex ratio in Medes Islands populations of both species was 1:1, while in Cape of Palos sex ratio was significantly male biased (1:7) in P. clavata, and female biased (1.7:1) in E. singularis populations. Spawning timing occurred in all cases coinciding with a marked increase in sea-water temperature in spring, and after the most successful feeding season, but comparing localities there was a clear temporal shift in the time of gametes release, appearing well linked to the shift in sea-water temperature rising in spring in both sites at the depth where populations are placed. Therefore, in this study the temperature appears as the main synchronizing factor of gonadal development within these populations. Significant differences in gonadal volume per polyp were found in both species owing mainly to differences in the number of gonads per polyp between populations, with Cape of Palos populations displaying higher values in both studied species, suggesting that the exposition to different local conditions may be reverted in a different gonadal output. But the observed patterns in lipid concentrations levels in gorgonians disable us to conclude that lipid concentration levels explain the observed differences in gonadal output found in this study.  相似文献   
568.
Perfluorinated compounds (PFCs) are man-made chemicals for which endocrine disrupting properties and related possible side effects on human health have been reported, particularly in the case of an exposure during the early stages of development, (notably the perinatal period). Existing analytical methods dedicated to PFCs monitoring in food and/or human fluids are currently based on liquid chromatography coupled to tandem mass spectrometry, and were recently demonstrated to present some limitations in terms of sensitivity and/or specificity. An alternative strategy dedicated to the analysis of fourteen PFCs in human breast milk was proposed, based on an effective sample preparation followed by a liquid chromatography coupled to high resolution mass spectrometry measurement (LC-HRMS). This methodology confirmed the high interest for HRMS after negative ionization for such halogenated substances, and finally permitted to reach detection limits around the pg mL(-1) range with an outstanding signal specificity compared to LC-MS/MS. The proposed method was applied to a first set of 30 breast milk samples from French women. The main PFCs detected in all these samples were PFOS and PFOA with respective median values of 74 (range from 24 to 171) and 57 (range from 18 to 102) pg mL(-1), respectively. These exposure data appeared in the same range as other reported values for European countries.  相似文献   
569.
570.
Residential concentrations of formaldehyde have been associated with poor respiratory health in children, where formaldehyde has been measured using stationary monitors inside homes. Although children spend most of their time indoors at home, there are few studies of children’s personal exposure to formaldehyde. The aim of this study was to investigate the relationship between personal exposure formaldehyde concentrations, microenvironmental concentrations and time weighted exposure estimates in children.Forty-one primary school children (aged between 9 and 12 years) wore a personal passive sampler over two 24 h periods in two seasons and completed 24 h daily activity diaries and a questionnaire about lifestyle and behaviour. Samplers were co located indoors at home, outdoors at centralised locations and indoors at school for the corresponding period.Personal exposure formaldehyde concentrations in this group of children were generally low with a geometric mean concentration of 9.1 ppb (range <detection limit to 27.3 ppb). There were strong correlations between personal exposure concentrations and both domestic indoor (rs = .779, p < 0.001) and time weighted estimated (rs = .802, p < 0.001) concentrations. The time weighted model did not improve the estimate of personal exposure compared with stationary indoor concentrations. Indoor air concentration measured with a single stationary monitor was a suitable surrogate for personal exposure.  相似文献   
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