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961.
William?Zonta Axel?Mauroy Frederic?Farnir Etienne?ThiryEmail author 《Food and environmental virology》2016,8(4):275-282
Human noroviruses (HuNoV) are amongst the leading causes of acute non-bacterial gastroenteritis in humans and can be transmitted via person-to-person contact, via contact with contaminated surfaces or by consumption of contaminated food. Contaminated surfaces in healthcare settings contribute to the transmission of viruses. No-touch automated room disinfection systems might prevent such a spread of contamination and thus their virucidal effect needs to be evaluated. The aim of this study was to assess the efficacy of a nebulization system spraying hydrogen peroxide on two main surrogates of HuNoV, namely murine norovirus (MNV) and feline calicivirus (FCV). The viruses were dried on cover glasses and on stainless steel discs and exposed to nebulization. The number of infectious viral particles and genomic copies before and after the nebulization was compared. The efficacy in reducing infectivity of both surrogates was demonstrated. For the infectious viral titre of MNV and FCV, a log10 reduction factor ≥4.84 and 4.85 was observed after nebulization, respectively, for tests on cover glasses and ≥3.90 and 5.30, respectively, for tests on stainless steel discs. Only low reductions in genomic copy numbers were observed for both surrogates. The nebulization of hydrogen peroxide showed a clear virucidal effect on both HuNoV surrogates, MNV and FCV, on two different carriers and the use of nebulization should be promoted in complementarity with conventional disinfection methods in healthcare settings and food processing facilities to reduce viral load and spread of contamination. 相似文献
962.
分析了我国农村环境污染问题及成因,总结了墨江农村环境整治现状。深入调查了卡房村污染状况,核算了污染负荷,摸清了污染原因,提出了对其进行农村综合整治的思路和措施,并进行了效益分析。 相似文献
963.
Thomas?WinklerEmail author Wilfried?Winiwarter 《Mitigation and Adaptation Strategies for Global Change》2016,21(8):1181-1196
In the present paper, national and externally organized projections of greenhouse gas emissions for Austria were compared to gain insight on the underlying scenario data assumptions. National greenhouse gas emission trends extend until 2030, an assessment of European Union (EU) countries to 2050. In addition, data for 2000–2100 was extracted from the global emission database described by the Representative Concentration Pathways (RCP). By identifying trends in these projections, it was possible to produce (a) a long-term assessment of national scenarios until 2100, (b) an assessment of the ambition level toward national climate strategies, and (c) a standardized method to compare trends across countries. By extracting RCP data, Austrian’s methane, nitrous oxide, and carbon dioxide emissions up to 2100 could be projected for all sources as well as specific sectors. With respect to the RCP scenario emission data, national projections did not seem to employ the mitigation potentials available for the most stringent RCP scenario, RCP2.6. Comparing projections that supported the EU Climate Strategy 2030 with national projections revealed similar trends. Because RCP2.6 is the only scenario consistent with a 2 °C global warming target, and it is much more ambitious than any of the national or European projections, further measures will be required if Austria is to adequately contribute to this widely accepted policy goal. 相似文献
964.
Carbon labels are innovative medium and tools for climate change communication and low-carbon marketing. This study aims at examining how college students are aware of low-carbon and carbon labels, whether they are more willing to communicate low-carbon ideas, and also the determinants affecting their interpersonal communication of carbon labels. The multiple regression analysis shows that Chinese college students’ willingness of interpersonal communication of carbon labels are significantly influenced by their awareness of climate change crisis, the perceived value of carbon labels, the consideration of product environmental attributes, the preferences of carbon labels, the household background, and their educational background. In response to these factors, this paper proposes, in a public perspective, the strategies to enhance the dissemination of carbon labels. 相似文献
965.
某煤业有限公司清洗锅炉产生的废液中含有大量的铁离子与H^+,具有腐蚀性危险特性,属于危险废物。本工程实例利用酸碱中和及氧化絮凝沉淀的原理,消除了该废酸液的腐蚀性危险特性,同时降低了废酸液中的铁离子以及废酸液的色度、浊度,为后续的深度治理提供了便利。对高含铁废酸液的治理有一定的借鉴意义。 相似文献
966.
967.
968.
Queen conch, Strombus gigas, is a commercially important gastropod that has been exploited throughout the Caribbean islands for thousands of years. Shell
middens in the region are the physical record of a long-term fishery and their study can provide valuable information on selectivity
patterns followed by fishermen and on resulting morphological shifts reflected by shells. In this study, we surveyed 27 middens
located at Los Roques, Venezuela, to assess pre-Columbian and modern fisheries and measure their impact on local populations
of queen conch. Pre-Columbian middens, covering a period of approximately 350 years of exploitation (1160–1540 A.D.), were
mostly composed of adult shells (89%) and mean length of catch was estimated at 22.4 ± 0.2 cm (mean ± SE). A decrease in mean
length of catch was observed throughout the modern fishery regime, estimated at 22.2 ± 0.3 cm in 1950–1971 and 20.0 ± 0.3 cm
in 1990–1995. Higher proportions of immature individuals ranging from 48 to 67% were found in modern middens. Additionally,
a decrease in mean length of mature individuals was detected throughout the modern fishery regime. The appearance of younger
and smaller specimens is considered as a sign of heavy exploitation of local populations of queen conch during modern fisheries.
Pre-Columbian middens in contrast, permitted to establish a relative baseline from which to compare values registered throughout
modern times. 相似文献
969.
970.
Konstanze Sch?nthaler 《Umweltwissenschaften und Schadstoff-Forschung》2001,13(2):107-116
Am Beispiel des l?nderübergreifenden Biosph?renreservates Rh?n wurde das Konzept einer ?kosystemaren Umweltbeobachtung konkretisiert. Die Arbeiten dienten der Operationalisierung der hohen fachlichen Anforderungen des Rats von Sachverst?ndigen für Umweltfragen an eine ‘Allgemeine ?kologische Umweltbeobachtung’, die medienund sektorübergreifende sowie m?glichst weitgehend harmonisierte Datenerhebungen und eine integrierte Datenauswertung vorsieht. Es werden die Bausteine einer stufenweisen Harmonisierung der Datenerhebung und Auswertung vorgestellt. Vertiefend behandelt werden Fragen nach methodischen Ans?tzen für eine nachvollziehbare Auswahl von Beobachtungsr?umen und Messtandorten sowie für die r?umliche Verallgemeinerung von Beobachtungsergebnissen. Das Konzept der ?kosystemaren Umweltbeobachtung nutzt hierfür das Instrument der bundesweiten standort?kologischen Raumgliederung sowie geostatistische Verfahren zur r?umlichen Zusammenführung bestehender Beobachtungsprogramme und Messnetze. Ferner werden M?glichkeiten aufgezeigt, wie mit der Durchführung hydrologischer Gebietsanalysen und mit einem ?kosystemarem Wasserhaushaltsmodell auf der Grundlage verfügbarer Daten integrierende Aussagen zur Entwicklung von Wassereinzugsgebieten getroffen werden k?nnen. 相似文献