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A simple, rapid and sensitive GC–MS method for the determination of dithiocarbamate fungicide propineb [polymeric zinc propylenebis (dithiocarbamate)] and an improved HPLC procedure for the simultaneous determination of its main metabolite, propylenethiourea, and ethylenethiourea, the main metabolite of all ethylenedithiocarbamates, in airborne samples are described. The method for the analysis of propineb involves the evolution of carbon disulfide (CS2), under acidic conditions in the presence of stannous chloride, extraction of the generated CS2 into a layer of isooctane which is then analyzed for CS2 content by GC–MS in SIM mode. Under the optimum conditions, the retention time of CS2 was 1.89 min and the total time of chromatographic analysis was 5 min. Recoveries from spiking glass microfibre filters (GF/A) and silica gel filters were 86 ± 7 (n = 9) and 89 ± 4 (n = 9), respectively. The limit of detection is 0.7 ng per filter, which is equivalent to about 0.8–1.0 ng m−3 in air. In parallel, an HPLC method with ultraviolet detection is presented for the simultaneous analysis of the metabolites. Separation of the two metabolites was attained in less than 5 min. Recoveries from spiking GF/A and silica gel filters for ethylenethiourea were 100 ± 1 (n = 3) and 98 ± 2 (n = 3), respectively, while for propylenethiourea were 102 ± 1 (n = 3) and 98 ± 1 (n = 3), respectively. The detection limits are about 36–43 and 40–49 ng m−3 in air for ethylenethiourea and propylenethiourea, respectively. All the analytes spiked in the filters are proven to be stable for more than one month, at −4 °C. 相似文献
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Stelios Katsanevakis Maria Thessalou-Legaki Constantina Karlou-Riga Eugenia Lefkaditou Evagelos Dimitriou George Verriopoulos 《Marine Biology》2007,151(3):949-959
Allometric growth investigations are usually conducted by fitting the allometric model (L)
(y, x are morphometric characters and b the allometric exponent), which is quite simple both conceptually and mathematically, and its parameters are easy to estimate
by linear regression. However b is not necessarily constant and it may change either continuously or abruptly at specific breakpoints; thus, the simple L
model quite often fails to describe allometric growth successfully. In the current context, a better alternative is proposed,
based on Kullback–Leibler (K-L) information theory and multi-model inference (MMI). Allometric growth was investigated in
eight marine species: the bivalves Pecten jacobaeus and Pinna nobilis, the squids Todarodes sagittatus and Todaropsis eblanae, the crab Pachygrapsus marmoratus (females), the ghost shrimp Pestarella tyrrhena (males), and the fishes Trachurus trachurus and Sparus aurata. In each of the eight species, a pair of body parts was measured and the allometric growth of one body part in relation to
the other (reference dimension) was studied, by fitting five different candidate models including: the simple allometric model,
two models assuming that b changed continuously and two other assuming that b had a breakpoint. For each species, the ‘best’ model was selected by minimizing the small-sample, bias-corrected form of
the Akaike Information Criterion. To quantify the plausibility of each model, given the data and the set of five models, the
‘Akaike weight’ w
i
of each model was calculated; based on w
i
the average model was estimated for each case. MMI is beneficial, more robust, and may reveal more information than the classical
approach. As demonstrated with the given examples, estimation of b from the linear model, when it was not supported by the data, revealed some characteristic pitfalls, such as concluding positive
allometry when there is actually negative or vice versa, or reporting allometry when the data in reality support isometric
growth or vice versa. 相似文献
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The World Summit on Sustainable Development (WSSD) met from 26 August to 4 September 2002, in Johannesburg, South Africa. Its goal was to hold a 10-year review of the 1992 UN Conference on Environment and Development and to reinvigorate global commitment to sustainable development. Main outcomes include the reaffirmation of sustainability as a basic worldwide need, the establishment of a World Solidarity Fund, the eradication of poverty and the agreement on particular attention to the needs of the African countries. However, there is also a great failure. It failed to address the issue of environmental education (EE). The need for implementation and support of the greatest tool, which can lead to action, i.e. the need for specific knowledge, was never stated. Issues of knowledge, access to information, critical thinking, evaluation, assessment, even dispute and doubt, i.e. components that make citizens actively participate in the environmental decision process, were not addressed. Delegates in Johannesburg managed to decide upon the need for reaction, without mentioning EE, the necessary prerequisite. 21,000 people discussed sustainability targets, but forgot to consider how we will reach them. One may think that EE was not discussed because it has already been successfully implemented; maybe the worldviews are that citizens do actively participate in environmental decision-making. Or perhaps we can still be so naïve, as to simply forget what we are talking about. 相似文献
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Public Participation Mechanisms in Environmental Disasters 总被引:1,自引:0,他引:1
This paper examines the role of public participation mechanisms in certain major environmental disasters. It examines situations in which people’s lifestyles or their lives have been directly threatened, and thus elicited citizen participation. Threatening issues often seem morally, physically, socially, economically, religiously, and otherwise unacceptable to a group. As will be presented in this paper, citizens voluntarily participate in a community activity when they see that their way of life has been threatened. An introductory historical perspective, the legal framework upon which it is based, and background information on the participatory mechanisms, all emphasizing the importance and need for empowering citizens with participatory skills so as to bring changes in the existing educational, legal, and social systems are presented. The major environmental accidents/disasters of Minamata, Japan; Bhopal, India; Seveso, Italy; Chernobyl, Ukraine; and Exxon-Valdez, Alaska are discussed, mainly to indicate the reaction, and the participatory mechanisms used by the affected communities in each of the sudden disasters that occurred. If citizens worldwide had been active participants in the environmental issues, it is quite possible that we would have experienced fewer environmental accidents. 相似文献
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An analytical method was developed and tested for the simultaneous determination of chlorothalonil and its main metabolite 4-hydroxychlorothalonil, in airborne samples. High performance liquid chromatography equipped with Ultra-violet detector was used to separate and quantify the analytes. Glass microfibre filters for the collection of the analytes' particles were tested. Solid sorbents, such as Tenax, Florisil, XAD-2 and silica gel, were studied to find out the most suitable material for the collection of the analytes in the gas phase. The results have shown that only chlorothalonil was trapped in the vapor phase with highest results obtained when silica gel was the sorbent of choice. Linearity was demonstrated in a wide concentration range 0.01-10.00 mg L(-1). Recoveries from spiked glass microfibre filters and silica gel cartridges for chlorothalonil and 4-hydroxychlorothalonil were almost quantitative. The quantification limits were calculated to be 8.4 and 19.6 ng m(-3) in air for chlorothalonil and 4-hydroxychlorothalonil, respectively. The two analytes spiked on the GF/A filters and silica gel cartridges were proven to be stable for more than 15 days, at 4degrees C and ambient temperature. The applicability of the present method was demonstrated by the analysis of the chlorothalonil and its metabolite in greenhouse air. 相似文献
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Constantina Alina Hossu Ioan Cristian Ioja Lawrence E. Susskind Denisa L. Badiu Anna M. Hersperger 《Ambio》2018,47(7):816-830
A critical challenge in natural resource management is to bring all stakeholders together to negotiate solutions to critical problems. However, various collaborative approaches to heading off conflicts and resolving natural resource management disputes have been used. What drives these efforts, however, still needs further research. Our study provides a systematic look at the drivers likely to initiate collaborative problem-solving efforts in four cases in Romania. We use Emerson’s et al. (2012) framework for collaborative governance and multi-value qualitative comparative analysis (mvQCA) to analyze cases involving endangered species, restrictions on forest harvest, conflicts associated with infrastructure development projects, and disputes over the management of environmentally sensitive areas. Our findings contribute to the already existing collaborative governance literature indicating which of the four factors: uncertainty, interdependence, consequential incentives, and leadership, in which combination, are necessary and sufficient to spur collaborative resource management efforts. Our results showed that in Romania the initiation of collaboration is best explained by positive consequential incentives (i.e., financial opportunities) which has determined leaders to take initiative. This study provides additional information for the complicated process of natural resource management which is often overriding collaboration by investigating what enables and constrains collaborative efforts in a country where natural resources were managed and used according to the principles of central planning. 相似文献
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The present paper acknowledges the need for sustainable development education in Cuba, after a short review of their national health status and educational system. The environmental situation of the island is outlined, including the role played by environmental education (EE) in the current environment system. The-EE in Cuba is presented, and the problems related to its implementation are analyzed. Recommendations and possible solutions towards the use of education for sustainability as a tool for environmental management are presented, so as to prove the need for environmental awareness management in Cuba. 相似文献
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In Greece, environmental interpretation is in its infancy as an academic field. In particular, there are no nature guides or specific conservation objectives, and no professional training for non-formal environmental educators and/or interpreters. In view of the United Nations Decade of Education for Sustainable Development, this paper develops and recommends a training model for environmental educator/interpreter guides in protected areas and sensitive ecotourism settings in Greece. An investigation was undertaken into training programmes in developed and less developed ecotourism countries, where environmental interpretation is practiced in the sustainable management of sensitive areas. The proposed model is based mainly on interpretive training programmes of other developed and less developed countries. This model introduces the art of environmental interpretation as a form of non-formal environmental education, integrated in strategic communication in protected areas and sensitive ecotourism areas in Greece. The developed model takes into consideration the special social settings and biophysical environments of Greece. Moreover, a professional environmental interpreter group is recommended to support the role of management authorities in protected areas. 相似文献
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