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951.
An international workshop held in the spring of 2002 convened a group of technical experts to address monitoring, modeling,
and management of PCBs within the Detroit River-Western Lake Erie basin. Participants shared and discussed a diverse set of
research data bases pertaining to PCB levels within the region, discussed observed changes within different components of
the local ecosystem, and identified several primary issues impacting future PCB management strategies. Results presented at
the workshop indicate dramatic reductions in PCB contamination levels have been observed in much of study area between the
late 1970s and mid-1990s. Estimates of loadings attributable to water and atmospheric sources have generally declined, as
have PCB concentrations in herring gull eggs, smelt and walleye. Nevertheless, additional improvements have not been observed
during recent years and elevated contamination levels remain a concern within local hot spots, particularly in the lower Detroit
River and Trenton Channel. A primary recommendation broadly supported by workshop participants is the need to maintain, support,
and coordinate a comprehensive ecosystem monitoring program for the Detroit River-Western Lake Erie basin, one that incorporates
both near-field and far-field monitoring elements. Such a program is crucial to provide necessary data in support of understanding
ecosystem trends, calculating annual mass loadings to the system, assessing impacts of remediation actions, developing improved
modeling frameworks, and formulating cost-effective management strategies for the future. 相似文献
952.
Will Smith 《Ambio》2022,51(3):485
Zoonotic disease emergence has become a core concern of biodiversity conservation amid the ongoing impacts of the COVID-19 pandemic. Major international conservation groups now comprehensively center larger human–nature imbalances not only as problems of global public health but as a core challenge of the conservation movement, alongside habitat destruction, biodiversity loss and climate change. There is, however, little consideration of how new biosecurity concerns might alter conservation practice with unexpected and potential harmful impacts on human communities, particularly in developing nations with significant human–wildlife interfaces. Reviewing emerging policy positions from key conservation organizations, this article argues that the proposed responses to the COVID-19 pandemic hold the potential to (a) amplify existing people-park conflicts, and (b) generate new tensions by integrating global systems of viral surveillance into biodiversity conservation. I conclude that the close integration of biosecurity concerns into conservation policies requires greater acknowledgment of the unique challenges for human communities.Supplementary InformationThe online version of this article (10.1007/s13280-021-01576-0) contains supplementary material, which is available to authorized users. 相似文献
953.
煤矿环境噪声对居民健康影响的调查 总被引:2,自引:0,他引:2
参照国家环境噪声标准,在西山官地矿,选择了噪声在50dB(A)以下两类居民区,对16岁上的居民选256名为本次调查对象。监测结果,户外最75dB(A),均超过国家规定标准。在50dB(A)以上的环境下生活、工作和学习的居民神经系统和听力均有不同程度的损伤,而且损伤程度与居住年限有密切关系。神衰阳性率10年以上者,50dB(A)以上34.28%,50dB(A)以下为13.55%。语频听损检出率50d 相似文献
954.
955.
Groundwater is a basic source of drinking water supply for urban and rural areas. This is especially the case for communities located in arid and semi-arid regions that rely on groundwater for drinking purposes. The present study set out to assess the potential health impacts of water impurities and to investigate the qualitative status of drinking water in Robat Karim rural areas, located in southwest Tehran, Iran. A total of 66 samples were collected from the water distribution network of 11 villages (33 sampling points, on two occasions) during September 2020 and were tested in terms of the most common quality parameters such as pH, mercury (Hg), lead (Pb), copper (Cu), zinc (Zn), chloride (Cl–), chlorate (ClO3–), nitrite (NO2–), nitrate (NO3–), and flouride (F–). Multiple methods and indexes including water quality index (WQI), hazard quotient (HQ), and hazard index (HI), were worked out to assess the quality of water and health risk assessment of NO3– Pb2+ and Hg2+. The results revealed that 33% and 90% of sampling sites have significantly high nitrate and total hardness (TH) concentrations, exceeding the maximum permissible limits set by World Health Organization (WHO; 50 and 200 mg/L, respectively). Furthermore, five sampling points exhibited poor WQIs mainly related to NO3– and TH. HQ values higher than 1 for nitrate were noticed in most sampling locations. Except for one sampling point, the HQ obtained for Pb2+ and Hg2+ were below 1 indicating no obvious health hazard. This study represents that children and infants are at higher risk of chronic toxicity by excess NO3– intake. The health hazard that is yet imposed on the community by NO3– necessitates regular monitoring of drinking water, the use of advanced technologies to purify water or otherwise alternative resources should be proposed. 相似文献
956.
Is being a leader a mixed blessing? A dual‐pathway model linking leadership role occupancy to well‐being 下载免费PDF全文
Recent leadership research has drawn greater attention to how the well‐being of leaders influences leadership behaviors, follower performance and well‐being, and overall leadership effectiveness. Yet little attention has been paid to the relationship between occupying leadership positions and job incumbents' well‐being. This research addresses this question by developing and testing a dual‐pathway model. Our model proposes that incumbency in leadership positions is positively related to high levels of both job demands and job control, whereas job demands and job control have offsetting effects on well‐being. Results based on a longitudinal sample revealed that employees who transitioned from nonleadership positions to leadership roles showed trajectories of increasing job demands and job control, whereas such trends were weaker among those who remained in nonleadership positions. Findings from three additional samples generally demonstrated that leadership role occupancy was indirectly related to various indices of psychological and physiological well‐being through job demands and job control. Because the signs of the indirect effects through job demands and job control differed in expected ways, the overall relationship between leadership role occupancy and the well‐being outcomes was generally small and nonsignificant. We discuss research and practical implications of our framework and findings for organizations, employees, and leaders. 相似文献
957.
Introduction: Injuries and work-related musculoskeletal disorders (MSDs) are common among masons. SAfety Voice for Ergonomics (SAVE) integrates training in ergonomic and safety problem-solving skills into masonry apprenticeship training. The purpose of this study was to assess the efficacy of text messaging to reinforce SAVE program content. Method: SAVE effectiveness was evaluated at masonry apprenticeship training centers across the United States by comparing three experimental groups: (1) Ergonomics training, (2) Ergonomics and Safety Voice training, and a (3) Control. Apprentices received SAVE training with their standard instruction. To reinforce classroom training, refresher training was implemented by sending weekly text messages for six months. Half of the text messages required a response, which tested knowledge or assessed behavior, while the remaining reiterated knowledge. Apprentices (n = 119) received SAVE text messages. Response rates and percentage of correct responses were compared with chi-square tests and independent group t-tests. Multivariable logistic regression analysis predicted apprentice response with selected demographic and work experience variables. Finally, feedback on of the use of text messaging was obtained. Result: Of 119 participants, 61% (n = 72) responded to at least one text message. Logistic regression revealed that being a high school graduate and a brick and block mason significantly affected the odds of responding. Sixty-nine percent of apprentices agreed that text messages reinforced SAVE content. Conclusion: Even though there was no training center requirement to respond, the high response rate suggests that text messaging can effectively be used to reinforce ergonomics and safety voice training for both knowledge and behavior. Practical Application: The prevalent use of text messaging creates opportunities to reinforce health and safety training and engage workers, especially for populations that may be at various locations over time such as construction sites. Instructors and practitioners should consider the utility of text messaging for supporting their training and safety programs. 相似文献
958.
为开展隐伏断层探测,明确断层空间位置和构造属性,在此基础上合理避让或采取有效的工程措施,可以有效减轻地震灾害损失。在昔格达断裂带某区域,采用地下氡气测量法与音频大地电磁法相结合的方法探测隐伏断层。结果表明:2种方法所推断的断层区域较为吻合。地下氡气测量法简单方便,但无法确定断裂结构的深部延伸及产状变化,音频大地电磁法勘探深度大、效率高但干扰因素较多,具有多解性,二者结合的断层探测方法在研究区效果良好,对类似地区开展断层探测具有一定的借鉴和指导意义。 相似文献
959.
An Index to Determine Vulnerability of Communities in a Coastal Zone: A Case Study of Baler, Aurora, Philippines 总被引:1,自引:0,他引:1
A coastal community vulnerability index (CCVI) was constructed to evaluate the vulnerability of coastal communities (Buhangin, Pingit, Reserva, Sabang, and Zabali) in the municipality of Baler, Aurora, Philippines. This index was composed of weighted averages of seven vulnerability factors namely geographical, economic and livelihood, food security, environmental, policy and institutional, demographic, and capital good. Factor values were computed based on scores that described range of conditions that influence communities’ susceptibility to hazard effects. Among the factors evaluated, economic and livelihood, policy and institutional and food security contributed to CCVI across communities. Only small variations on CCVI values (i.e., 0.47–0.53) were observed as factor values cancelled out one another during combination process. Overall, Sabang received the highest CCVI, which was contributed mainly by geographical and demographic factors. This technique to determine factors that influenced communities’ vulnerability can provide information for local governments in enhancing policies on risk mitigation and adaptation. 相似文献
960.
Increasing use of nickel oxide nanoparticles (NiO NPs) necessitates an improved understanding of their potential impact on human health. Previously, toxic effects of NiO NPs have been investigated, mainly on airway cells. However, information on effect of NiO NPs on human liver cells is largely lacking. In this study, we investigated the reactive oxygen species (ROS) mediated cytotoxicity and induction of apoptotic response in human liver cells (HepG2) due to NiO NPs exposure. Prepared NiO NPs were crystalline and spherical shaped with an average diameter of 44 nm. NiO NPs induced cytotoxicity (cell death) and ROS generation in HepG2 cells in dose-dependent manner. Further, ROS scavenger vitamin C reduced cell death drastically caused by NiO NPs exposure indicating that oxidative stress plays an important role in NiO NPs toxicity. Micronuclei induction, chromatin condensation and DNA damage in HepG2 cells treated with NiO NPs suggest that NiO NPs induced cell death via apoptotic pathway. Quantitative real-time PCR analysis showed that following the exposure of HepG2 cells to NiO NPs, the expression level of mRNA of apoptotic genes (bax and caspase-3) were up-regulated whereas the expression level of anti-apoptotic gene bcl-2 was down-regulated. Moreover, activity of caspase-3 enzyme was also higher in NiO NPs treated cells. To the best of our knowledge this is the first report demonstrating that NiO NPs caused cytotoxicity via ROS and induced apoptosis in HepG2 cells, which is likely to be mediated through bax/bcl-2 pathway. This work warrants careful assessment of Ni NPs before their commercial and industrial applications. 相似文献