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Food and Environmental Virology - Norovirus is a major cause of foodborne-associated acute gastroenteritis (AGE) outbreaks worldwide. Usually, food products are contaminated either during...  相似文献   
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Heterogeneous photocatalysis is highlighted to treat volatile organic compound (VOC) emission. Then, this work analysed the influence of palladium (Pd) content loaded in TiO2 on n-octane and iso-octane photodegradation. For this, TiO2 was loaded with Pd in different contents: 0.4%, 0.7%, and 1.0%. The samples were characterized, and the photodegradation experiments were conducted by Pd/TiO2/UV process. The characterization analyses showed that the metal presence did not change the catalyst structure or its surface area; however, it reduced the bandgap energy. The photocatalytic results proved that palladium improved n-octane degradation from 62% (pure TiO2) to 92.6% (0.4%Pd/TiO2) and, iso-octane degradation enhanced from 59% (pure TiO2) to 90.6% (0.7%Pd/TiO2); all results were obtained in the space time of 39 s. Therefore, 0.4%Pd/TiO2 and 0.7%Pd/TiO2 showed better oxidation results to degradation n-octane and iso-octane, respectively. The kinetic model of pseudo-first order showed a good fit for the data of both VOCs. Heterogeneous photocatalysis with Pd/TiO2 showed to be an adequate technique to reduce VOCs emission.

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Regional Environmental Change - The State of Mato Grosso in Brazil has undergone intensive land use changes over the past decades. Native ecosystems have been converted into agrosystems for the...  相似文献   
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Small-scale vertical patterns of larval distribution were studied at a very nearshore larval fish assemblage, during the spring–summer period of several years, at two depth strata (surface and bottom) using sub-surface and bottom trawls. A total of 4,589 larvae (2,016 from surface samples and 2,573 from bottom samples) belonging to 62 taxa included in 22 families were collected. Most larvae belonged to coastal species. Although inter-annual variations in larval density and diversity could be found, total larval abundance was always higher near the bottom whereas diversity was higher at the surface. A marked distinction between the structure of surface and bottom assemblages was found. Sixteen taxa explained 95% of the similarity among surface samples. Larvae which contributed most to this similarity included species like clupeiformes, sparids and serranids, and also blenniids, tripterygiids and some labrids. In the bottom samples, fewer species were present, with only six taxa, almost exclusively from species which lay demersal eggs, contributing to 95% of the similarity between samples. Larvae present at the surface were significantly smaller than at the bottom. For some of the most abundant species found at the bottom, only small larvae occurred at the surface while the whole range of sizes was present at the bottom, indicating that larvae may be completing the entire pelagic phase near the adults’ habitat. These results indicate that larval retention near the reefs probably occurs for these species, although for others dispersal seems to be the prevailing mechanism.  相似文献   
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The growing importance of technical regulation affecting the use and sale of chemical products is a topic of interest not only for the chemical industry, but also for governments, nongovernmental organizations, consumers, and interested communities. The results of such regulation on behalf of the environment, health and safety of individuals, as well as its economic effects on industrial activity, are well understood in the United States and recently in the European Union. In less developed countries, however, the general level of public understanding of these issues is still minimal. It is common knowledge that the so-called "regulatory asymmetry" between countries at different levels of development contributes to the establishment of technical barriers to trade. Such asymmetries, however, also have other impacts: the displacement of polluting industrial sectors to countries which have less demanding regulations, the concentration of unsafe and harmful environmental conditions in certain parts of the globe, and the competitive disadvantage for industries located in countries where control is more rigid. This study analyses information on a wide range of technical regulations issued by World Trade Organization (WTO) members, and focuses on those regulations that affect the chemical industry. This information is available through the WTO Enquiry Points, organizations created in each country to administrate the Technical Barriers to Trade Agreement (TBT). This article consists of an analysis of 4,301 notifications of technical regulations by WTO member states in the 7-year period following the establishment of the WTO in 1995. Starting from this mass of information, 585 notifications that affect the circulation or use of chemical products were isolated. Of this group, 71% refer to only 15 countries. This group of notifications was further classified according to their motivation (the environment, health, safety), by the type of product affected (medications, fuels, hazardous products, etc.), by the type of country where it was established (developed, emerging or developing) and the existing conformity assessment mechanism (prohibition, licenses, certification, labeling, etc.). Beyond identifying tendencies in specific industrial sectors, the notifications studied here reach more than 100 chemical products, substances, preparations and other materials, which are subject to various levels of restrictions in different parts of the globe because of their composition or adverse reactions during their life cycles.  相似文献   
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Field studies of pesticide effects on birds often utilize indicator species with the purpose of extrapolating to other avian taxa. Little guidance exists for choosing indicator species to monitor the presence and/or effects of contaminants that are labile in the environment or body, but are acutely toxic, such as anticholinesterase (anti-ChE) insecticides. Use of an indicator species that does not represent maximum exposure and/or effects could lead to inaccurate risk estimates. Our objective was to test the relevance of a priori selection of indicator species for a study on pesticide exposure to birds inhabiting fruit orchards. We used total plasma ChE activity and ChE reactivation to describe the variability in anti-ChE pesticide exposure among avian species in two conventionally managed fruit orchards. Of seven species included in statistical analyses, the less common species, chipping sparrow (Spizella passerina), showed the greatest percentage of exposed individuals and the greatest ChE depression, whereas the two most common species, American robins (Turdus migratorius) and gray catbirds (Dumatella carolinensis), did not show significant exposure. Due to their lower abundance, chipping sparrows would have been an unlikely choice for study. Our results show that selection of indicator species using traditionally accepted criteria such as abundance and ease of collection may not identify species that are at greatest risk. Our efforts also demonstrate the usefulness of conducting multiple-species pilot studies prior to initiating detailed studies on pesticide effects. A study such as ours can help focus research and resources on study species that are most appropriate.  相似文献   
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