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211.
Gia Thanh Nguyen Jian Pu Takayuki Miura Hiroaki Ito Shinobu Kazama Yoshimitsu Konta An Van Le Toru Watanabe 《Food and environmental virology》2018,10(1):61-71
This study investigated the level of norovirus contamination in oysters collected at a lagoon receiving urban drainage from Hue City for 17 months (August 2015–December 2016). We also investigated the genetic diversity of norovirus GI and GII in oyster and wastewater samples by using pyrosequencing to evaluate the effect of urban drainage on norovirus contamination of oysters. A total of 34 oyster samples were collected at two sampling sites (stations A and B) in a lagoon. Norovirus GI was more frequently detected than GII (positive rate 79 vs. 41%). Maximum concentrations of GI and GII were 2.4 × 105 and 2.3 × 104 copies/g, respectively. Co-contamination with GI and GII was observed in 35% of samples. Norovirus GII concentration was higher at station A in the flood season than in the dry season (P = 0.04, Wilcoxon signed-rank test). Six genotypes (GI.2, GI.3, GI.5, GII.2, GII.3, and GII.4) were identified in both wastewater and oyster samples, and genetically similar or identical sequences were obtained from the two types of samples. These observations suggest that urban drainage and seasonal flooding contribute to norovirus contamination of oysters in the study area. 相似文献
212.
Thomas Fellmann Peter Witzke Franz Weiss Benjamin Van Doorslaer Dusan Drabik Ingo Huck Guna Salputra Torbjörn Jansson Adrian Leip 《Mitigation and Adaptation Strategies for Global Change》2018,23(3):451-468
Taking the European Union (EU) as a case study, we simulate the application of non-uniform national mitigation targets to achieve a sectoral reduction in agricultural non-carbon dioxide (CO2) greenhouse gas (GHG) emissions. Scenario results show substantial impacts on EU agricultural production, in particular, the livestock sector. Significant increases in imports and decreases in exports result in rather moderate domestic consumption impacts but induce production increases in non-EU countries that are associated with considerable emission leakage effects. The results underline four major challenges for the general integration of agriculture into national and global climate change mitigation policy frameworks and strategies, as they strengthen requests for (1) a targeted but flexible implementation of mitigation obligations at national and global level and (2) the need for a wider consideration of technological mitigation options. The results also indicate that a globally effective reduction in agricultural emissions requires (3) multilateral commitments for agriculture to limit emission leakage and may have to (4) consider options that tackle the reduction in GHG emissions from the consumption side. 相似文献
213.
Joyeeta Gupta Catrien Termeer Judith Klostermann Sander Meijerink Margo van den Brink Pieter Jong Sibout Nooteboom Emmy Bergsma 《Environmental Science & Policy》2010,13(6):459-471
Climate change potentially brings continuous and unpredictable changes in weather patterns. Consequently, it calls for institutions that promote the adaptive capacity of society and allow society to modify its institutions at a rate commensurate with the rate of environmental change. Institutions, traditionally conservative and reactive, will now have to support social actors to proactively respond through planned processes and deliberate steps, but also through cherishing and encouraging spontaneous and autonomous change, as well as allowing for institutional redesign. This paper addresses the question: How can the inherent characteristics of institutions to stimulate the capacity of society to adapt to climate change from local through to national level be assessed? On the basis of a literature review and several brainstorm sessions, this paper presents six dimensions: Variety, learning capacity, room for autonomous change, leadership, availability of resources and fair governance. These dimensions and their 22 criteria form the Adaptive Capacity Wheel. This wheel can help academics and social actors to assess if institutions stimulate the adaptive capacity of society to respond to climate change; and to focus on whether and how institutions need to be redesigned. This paper also briefly demonstrates the application of this Adaptive Capacity Wheel to different institutions. 相似文献
214.
John S. McLaren Todd V. Royer Robert W. Van Kirk Melissa L. Muradian 《Journal of the American Water Resources Association》2019,55(5):1323-1334
This study seeks to improve understanding of temperature patterns in reservoir outflows. We examined water temperatures in an irrigation storage reservoir, Island Park Reservoir, and its outflow, Henry’s Fork of the Snake River in eastern Idaho. Our objectives were to (1) quantify the extent to which daily temperature ranges in the reservoir outflow deviated from other reaches of the Henry’s Fork, and (2) test whether the reservoir’s net volume change during the summer — expressed as the volume of water remaining in the reservoir on September 1 — predicted mean summer temperature in the outflow. Two years of temperature data showed dampened diel temperature cycles in the reservoir outflow. Model selection with 17 years of climatic, hydrologic, and reservoir management variables found mean summer temperature in the outflow was best predicted by September 1 reservoir volume and average summer air temperature. Two years of weekly reservoir thermal profiles indicated large changes in reservoir volume eliminated cool hypolimnetic water and encouraged mixing, allowing warm epilimnetic water to be discharged into the outflow. Increases in future drought frequency and severity and increases in summer air temperatures could increase the frequency of occurrence of high mean summertime water temperatures in the outflow. Our study provides important information for local managers by quantifying influences on outflow temperatures and the downstream river ecosystem. 相似文献
215.
Anh Van Ngo Ha Thi Nguyen Chieu Van Le Rajeev Goel Mitsuharu Terashima Hidenari Yasui 《Journal of Material Cycles and Waste Management》2016,18(2):239-247
Microbial response on volatile fatty acids (VFAs) is a key for methane fermentation processes since accumulation of VFAs often causes an acidic failure, especially treating such organics as food wastes composed of mostly readily biodegradable materials. To evaluate the impact of VFA accumulation, a lab-scale continuous experiment was performed for 110 days with sequential feeding of heterogeneous food wastes. When the volumetric loading rate was increased from 6 to 8 kg-COD/m3/day, a sudden decrease of methane production was observed with an accumulation of acetate and propionate in the fermenter. After discontinuation of feeding for 10 days, the digestate in the fermenter was centrifuged and washed with tap water to reduce the VFAs to be acceptable concentration below 1000 mg-COD/L. Nevertheless, no recovery of methane production was observed and VFA concentrations consistently increased. To model the event, a modification of ADM1 was made assuming the methanogens in the fermenter were irreversibly inactivated under very high VFA. Also considering the different nature of the fed food wastes over 11 samples, decomposition kinetics of individual food wastes were manipulated. The modified ADM1 with methanogenic activity decay reasonably reproduced the responses for soluble material concentrations and methane gas production rate over the experimental period. 相似文献
216.
J. Gupta E. Bergsma C. J. A. M. Termeer G. R. Biesbroek M. van den Brink P. Jong J. E. M. Klostermann S. Meijerink S. Nooteboom 《Mitigation and Adaptation Strategies for Global Change》2016,21(6):883-903
The climate change problem calls for a continuously responding society. This raises the question: Do our institutions allow and encourage society to continuously adapt to climate change? This paper uses the Adaptive Capacity Wheel (ACW) to assess the adaptive capacity of formal and informal institutions in four sectors in the Netherlands: spatial planning, water, agriculture and nature. Formal institutions are examined through an assessment of 11 key policy documents and informal institutions are analysed through four case studies covering each sector. Based on these ACW analyses, both sector-specific and more general strengths and weaknesses of the adaptive capacity of institutions in the Netherlands are identified. The paper concludes that the most important challenge for increasing institutional adaptive capacity lies in combining decentralized, participatory approaches with more top-down methods that generate leadership (visions, goals) standards, instruments, resources and monitoring. 相似文献
217.
Paolo Ciavola Oscar Ferreira Piet Haerens Mark Van Koningsveld Clara ArmaroliAuthor vitae 《Environmental Science & Policy》2011,14(7):924-933
This paper describes the MICORE approach to quantify for nine field sites the crucial storm related physical hazards (hydrodynamic as well as morphodynamic) in support of early warning efforts and emergency response.As a first step historical storms that had a significant morphological impact on a representative number of sensitive European coastal stretches were reviewed and analysed in order to understand storm related morphological changes and how often they occur around Europe. Next, an on-line storm prediction system was set up to enable prediction of storm related hydro- and morphodynamic impacts. The system makes use of existing off-the-shelf models as well as a new open-source morphological model. To validate the models at least one year of fieldwork was done at nine pilot sites. The data was safeguarded and stored for future use in an open database that conforms to the OpenEarth protocols.To translate quantitative model results to useful information for Civil Protection agencies the Frame of Reference approach (
[Van Koningsveld et al., 2005]
and
[Van Koningsveld et al., 2007]
) was used to derive Storm Impact Indicators (SIIs) for relevant decision makers. The acquired knowledge is expected to be directly transferred to the civil society trough partnerships with end-users at the end of the MICORE project. 相似文献
218.
Trophic ecology of Rimicaris exoculata : a combined lipid abundance/stable isotope approach 总被引:1,自引:0,他引:1
The alvinocaridid shrimp Rimicaris exoculata is an abundant component of the biota of Mid-Atlantic Ridge hydrothermal vents. To determine the nutritional strategy of
this organism, we analysed the molecular abundance and carbon isotopic composition of its phospholipid fatty acids. High abundances
of n-7 fatty acids (>40% total fatty acids) were observed in R. exoculata muscle tissues, in bacterial epibionts scraped from its gill bailers, and from the bacterially infested metal sulphides that
the shrimp ingest. The phospholipid fatty acid abundance data indicates that the bacteria in the sulphides are closely related
to the bacterial epibiota inhabiting the shrimp gill bailers, carapace and other body parts. Compound specific δ13C analyses of the phospholipid fatty acids gave average values of −12‰ for the epibiont bacteria and −21‰ for the sulphide
bacteria. This difference may be largely due to the expression of different forms of RuBisCO (Forms I and II) which fractionate
against 13C to different extents. Carbon limitation within the shrimp epibiont population may be an additional factor. The δ13C values (mean = −13‰) of the saturated and monounsaturated fatty acids isolated from the muscle tissues of R. exoculata were very close to those of the epibionts, indicating that the predominant source of dietary carbon for the shrimp is their
epibionts, with a lesser contribution from free-living bacteria. The δ13C values (−26‰) of shrimp cholesterol were much more negative than those of the fatty acids, and this cholesterol is likely
to have derived from the oceanic photic zone.
Received: 26 June 1997 / Accepted: 6 November 1998 相似文献
219.
Arnold B. Bakker Wilmar B. Schaufeli Herman J. Sixma Willem Bosveld Dirk Van Dierendonck 《组织行为杂志》2000,21(4):425-441
This study among a sample of 207 general practitioners (GPs) uses a five‐year longitudinal design to test a process model of burnout. On the basis of social exchange and equity theory, it is hypothesized and found that demanding patient contacts produce a lack of reciprocity in the GP–patient relationship, which, in turn, depletes GPs' emotional resources and initiates the burnout syndrome. More specifically, structural equation analyses confirmed that—both at T1 and T2—lack of reciprocity mediates the impact of patient demands on emotional exhaustion. Emotional exhaustion, in turn, evokes negative attitudes toward patients (depersonalization), and toward oneself in relation to the job (reduced personal accomplishment). Moreover, this process model of burnout was confirmed at T2, even after controlling for T1‐scores on each of the model components. Finally, T1 depersonalization predicted the intensity and frequency of T2 patient demands, after controlling for T1 patient demands. This major finding suggests that GPs who attempt to gain emotional distance from their patients as a way of coping with their exhaustion, evoke demanding and threatening patient behaviors themselves. The theoretical and practical implications of these findings are discussed. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
220.
A refined exit, voice, loyalty, and neglect (EVLN) typology (Farrell, 1983) was examined. It was argued that the category of voice responses, that is, attempts to improve the situation, should be divided into two forms: considerate voice and aggressive voice. Considerate voice consists of attempts to solve the problem taking into account one's own concerns as well as those of the organization, and aggressive voice consists of efforts to win, without consideration for the concerns of the organization. In line with Farrell (1983), all categories of behavioral responses were assumed to differ on two dimensions, namely, destructive–constructive and active–passive. It was assumed that the responses can be ordered in a circumplex structure. Factor analyses of data from 233 teachers and maternity nurses demonstrated the empirical separability of the five categories of behavioral responses and supported the two‐dimensional structure of the model. Job satisfaction, especially satisfaction with supervision, seemed to promote considerate voice and loyalty (that was relabeled as patience), and suppress exit, aggressive voice, and neglect. Furthermore, the correlations between job satisfaction and the five responses provided additional support for the circumplex structure of the refined model. The pattern of responses runs in the following order: considerate voice, aggressive voice, exit, neglect, patience. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献