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381.
Mussel biomonitors are widely used as screening tools for polybrominated diphenyl ethers (PBDEs) in marine and aquatic environments. This study determined elimination rate coefficients (k(tot)) for eight PBDE and five PCB congeners in the freshwater mussel, Elliptio complanata, over a 120d depuration period. Elimination of BDE 15, 28, 47, 75 and 100 was similar to PCBs of equivalent hydrophobicity and negatively related to chemical K(OW). Rapid elimination of BDE 190 and an inferred rapid elimination of BDE 183 indicate mussels are capable of biotransformation of certain highly brominated PBDEs. Time to 90% steady state ranged from 48 to 66d for di- and tribromoDE congeners and from 91 to >250d for tetra- to hexabromoDE congeners. Given the long time periods required for steady state, mussel accumulated PBDE residues should be interpreted in the context of calibrated bioaccumulation models.  相似文献   
382.
Two microalgae, Chlorella pyrenoidosa and Chlamydomonas snowiae, were isolated from a high ammonia leachate pond in Li Keng Landfill, Guangzhou, China. Their growth and nutrient removal rates were determined in a serial dilution of landfill leachate under laboratory conditions, and their growth rates were compared with that of a C. pyrenoidosa strain isolated from a clean river. The results indicated the growth of all three algae was inhibited by high leachate concentrations, and the inhibition appears linked to high ammonia (ammoniacal-N670mgL(-1)). Significant amounts of ammoniacal-N, ortho-P and COD in the leachate were removed by the algae, with a positive correlation between algal growth and nutrient consumption. Not enough data are available to conclude that one strain was less inhibited by ammoniacal nitrogen or more effective at treating it. Phytotoxicity of leachate was reduced after algal growth, as demonstrated by a seed germination experiment with Brassica chinensis. The germination rates in 10%, 30% and 50% concentrations of algal-treated leachate were significantly higher than those in the same concentration but algal-free leachate.  相似文献   
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384.
Stakeholders’ nonmaterial desires, needs, and values often critically influence the success of conservation projects. These considerations are challenging to articulate and characterize, resulting in their limited uptake in management and policy. We devised an interview protocol designed to enhance understanding of cultural ecosystem services (CES). The protocol begins with discussion of ecosystem‐related activities (e.g., recreation, hunting) and management and then addresses CES, prompting for values encompassing concepts identified in the Millennium Ecosystem Assessment (2005) and explored in other CES research. We piloted the protocol in Hawaii and British Columbia. In each location, we interviewed 30 individuals from diverse backgrounds. We analyzed results from the 2 locations to determine the effectiveness of the interview protocol in elucidating nonmaterial values. The qualitative and spatial components of the protocol helped characterize cultural, social, and ethical values associated with ecosystems in multiple ways. Maps and situational, or vignette‐like, questions helped respondents articulate difficult‐to‐discuss values. Open‐ended prompts allowed respondents to express a diversity of ecosystem‐related values and proved sufficiently flexible for interviewees to communicate values for which the protocol did not explicitly probe. Finally, the results suggest that certain values, those mentioned frequently throughout the interview, are particularly salient for particular populations. The protocol can provide efficient, contextual, and place‐based data on the importance of particular ecosystem attributes for human well‐being. Qualitative data are complementary to quantitative and spatial assessments in the comprehensive representation of people's values pertaining to ecosystems, and this protocol may assist in incorporating values frequently overlooked in decision making processes.  相似文献   
385.
Graham W. Prescott  William J. Sutherland  Daniel Aguirre  Matthew Baird  Vicky Bowman  Jake Brunner  Grant M. Connette  Martin Cosier  David Dapice  Jose Don T. De Alban  Alex Diment  Julia Fogerite  Jefferson Fox  Win Hlaing  Saw Htun  Jack Hurd  Katherine LaJeunesse Connette  Felicia Lasmana  Cheng Ling Lim  Antony Lynam  Aye Chan Maung  Benjamin McCarron  John F. McCarthy  William J. McShea  Frank Momberg  Myat Su Mon  Than Myint  Robert Oberndorf  Thaung Naing Oo  Jacob Phelps  Madhu Rao  Dietrich Schmidt‐Vogt  Hugh Speechly  Oliver Springate‐Baginski  Robert Steinmetz  Kirk Talbott  Maung Maung Than  Tint Lwin Thaung  Salai Cung Lian Thawng  Kyaw Min Thein  Shwe Thein  Robert Tizard  Tony Whitten  Guy Williams  Trevor Wilson  Kevin Woods  Alan D. Ziegler  Michal Zrust  Edward L. Webb 《Conservation biology》2017,31(6):1257-1270
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long‐running civil war. With these transitions in mind, we used a horizon‐scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land‐tenure insecurity, large‐scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure‐ and energy‐project planning, and reforming land‐tenure and environmental‐protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.  相似文献   
386.
In recent years, construction safety has been a hot topic in Hong Kong. The Government of the Hong Kong Special Administrative Region (HKSAR) has launched different safety measures to improve the prevailing safety performance of the construction industry. The Pay for Safety Scheme (PFSS) has emerged as one of the major safety initiatives launched within the public sector construction industry since 1996. It aims to encourage the safety awareness by taking the contractor’s pricing for safety-related items out from the consideration of competitive bidding. The objective is to provide a concise review of the prevailing application of PFSS in Hong Kong in general, and to identify and analyse the key benefits of PFSS in construction through an industry-wide empirical questionnaire survey in particular. Altogether, 145 industrial practitioners who have derived extensive hands-on experience with the PFSS construction projects participated in the survey to indicate their levels of agreement to those 14 key benefits identified which were measured and analysed by factor analysis. The results of factor analysis indicated that the 14 individual benefits of implementing PFSS were consolidated under four underlying factors: (1) Enhancing safety climate and attitude; (2) Promoting effective safety-related communication; (3) Streamlining the safety procedures; and (4) Ensuring adequate safety training. A wider application of PFSS should be encouraged with a view to achieving better safety performance within the industry. It is recommended that a similar scheme to PFSS currently applied in Hong Kong may be developed for implementation in other regions or countries for international comparisons.  相似文献   
387.
Proof-of-principle disease models have demonstrated the feasibility of an intrauterine gene modification therapy (in utero gene therapy (IUGT)) approach to hereditary diseases as diverse as coagulation disorders, haemoglobinopathies, neurogenetic disorders, congenital metabolic, and pulmonary diseases. Gene addition, which requires the delivery of an integrating or episomal transgene to the target cell nucleus to be transcribed, and gene editing, where the mutation is corrected within the gene of origin, have both been used successfully to increase normal protein production in a bid to reverse or arrest pathology in utero. While most experimental models have employed lentiviral, adenoviral, and adeno-associated viral vectors engineered to efficiently enter target cells, newer models have also demonstrated the applicability of non-viral lipid nanoparticles. Amelioration of pathology is dependent primarily on achieving sustained therapeutic transgene expression, silencing of transgene expression, production of neutralising antibodies, the dilutional effect of the recipient's growth on the mass of transduced cells, and the degree of pre-existing cellular damage. Safety assessment of any IUGT strategy will require long-term postnatal surveillance of both the fetal recipient and the maternal bystander for cell and genome toxicity, oncogenic potential, immune-responsiveness, and germline mutation. In this review, we discuss advances in the field and the push toward clinical translation of IUGT.  相似文献   
388.
Solubilization of naphthalene and phenanthrene into the micelles formed by three different anionic surfactants was investigated for single, binary, and ternary mixtures including pyrene. The three surfactants were sodium dodecylbenzene sulfonate (SDDBS), monoalkylated disulfonated diphenyl oxide (MADS-C12), and dialkylated disulfonated diphenyl oxide (DADS-C12). The order of increasing solubility enhancement of naphthalene and phenanthrene was SDDBS < MADS-C12 < < DADS-C12, which indicates that the hydrophobic chains in micellar core play more important role for the solubilization of polycyclic aromatic hydrocarbons (PAHs) than the benzene rings in palisade layer of a micelle. The solubility enhancement of naphthalene was slightly changed in PAH mixtures. The solubility of phenanthrene was greatly enhanced in presence of naphthalene but reduced in presence of pyrene. The explanation for these results could be that less hydrophobic compounds can be solubilized at the interfacial region of a hydrophobic core, which reduces the interfacial tension between the core and water, and then the reduced interfacial tension can support a larger core volume for the same interfacial energy.  相似文献   
389.
We investigated how the two components of paternalistic leadership, namely authoritarianism and benevolence, jointly influenced work performance through their impacts on organization‐based self‐esteem (OBSE). Using a sample of 686 supervisor–subordinate dyads collected from a manufacturing firm in the People's Republic of China, we found that OBSE mediated the negative relationship between authoritarian leadership on one hand and subordinate task performance and organizational citizenship behavior toward the organization (OCBO) on the other. We also found that the negative effect of authoritarian leadership on subordinate OBSE, task performance, and OCBO was weaker when supervisors exhibited higher levels of leader benevolence. Also, OBSE mediated the joint effect of authoritarian leadership and benevolent leadership on subordinate task performance and OCBO. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
390.
单力 《环境》2006,(9):56-58
寻找石油、煤炭、天然气等化石能源的替代品,早已成为中国未来能源战略的关键,也是能源投资的新热点。这使得新能源市场变得日渐火热起来。在此之前,新能源市场一直以国家政策为出发点,调整发展战略,培育利润增长点。特别是,今年《可再生能源法》正式生效的利好信息,从法律层面给新能源市场的发展前景注入了充足的信心。  相似文献   
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