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111.
The aim of this study was to investigate the effect of relative humidity (RH) and temperature on norovirus (NoV) persistence as infectious particles on food-contact surfaces such as stainless steel and polyvinyl chloride (PVC). For this purpose, a new method combining enzymatic digestion with molecular beacon-based NASBA targeting the ORF1-ORF2 domain was developed to discriminate between infectious and noninfectious NoV. Stainless steel and PVC disks were contaminated with known amounts of human NoV and kept for 56 days at 7 and 20°C at high (86% ± 4%) and low (30% ± 10%) RH. NoV retained its putative infectivity for 56 days on PVC and for 49 days on stainless steel at 7°C and for 7 and 28 days, respectively, at low and high RH at 20°C on both tested surfaces. These results confirm that NoV persists in an infective state on inert surfaces for long periods of time and consequently may cause illness. The new molecular approach to detecting infectious NoV on inert surfaces may provide valuable information for evaluating environmental surface decontamination strategies.  相似文献   
112.
This paper attempts to examine whether information from valuation studies can help the design of policies adequate to reverse and halt the generally poor state of marine and coastal ecosystems of the Mediterranean and the Black Sea. Economic implications of managing coastal and marine environments are thus discussed by assessing the results of different valuation studies implemented in the area. Lessons and policy recommendations from existing literature are inferred to guide marine resources management decisions. One of our main findings is that there are extremely few published studies within the Mediterranean and Black Sea region which highlights the potential for future research on coastal and marine ecosystems ability to sustain different goods and services as a result of climate change and anthropogenic drivers in the area. However, results reveal that there are substantial positive economic values attached to marketed and non-marketed services provided by marine and coastal ecosystems that justify their sustainable use and management.  相似文献   
113.
This study analyzes the characteristics of publications on sustainability topics and education for sustainability in the Web of Science (WOS) database during the period ranging from 2005 to 2014. We identified the topics that are being studied within those subjects and other relevant topics. We also analyzed a special edition of the Journal of Cleaner Production on “Higher Education for Sustainable Development: Emerging areas,” published in January, 2014. Our approach was both qualitative and quantitative and aimed at qualifying and quantifying certain variables related to the scientific literature on the broad subject of sustainability. The number of published pieces in the WOS focusing on sustainability issues during the period from 2005 to 2014 was 5,924. In our analysis of the special edition of the Journal of Cleaner Production, we found and analyzed 17 abstracts and full papers. The main results of our survey highlight the education, educational research, environmental sciences, ecology, and engineering areas as including the greatest number of publications. Articles, as opposed to conference proceedings or reviews, accounted for 63% of the published documents, and the year 2013 showed the largest number of publications. Huisingh, Suciu, Katane, and Barth are the most published authors on these topics. Furthermore, management, environmental studies, ecology, and environmental sciences are the “hot topics” with the best search results, meaning articles of impact and high quality. Finally, it should be emphasized that publications on the subject of sustainability appear most often in the sciences.  相似文献   
114.
Somatic coliphages were quantified in 459 produce and environmental samples from 11 farms in Northern Mexico to compare amounts of somatic coliphages among different types of fresh produce and environmental samples across the production steps on farms. Rinsates from cantaloupe melons, jalapeño peppers, tomatoes, and the hands of workers, soil, and water were collected during 2011–2012 at four successive steps on each farm, from the field before harvest through the packing facility, and assayed by FastPhage MPN Quanti-tray method. Cantaloupe farm samples contained more coliphages than jalapeño or tomato (p range <0.01–0.03). Across production steps, jalapeños had higher coliphage percentages before harvest than during packing (p = 0.03), while tomatoes had higher coliphage concentrations at packing than all preceding production steps (p range <0.01–0.02). These findings support the use of targeted produce-specific interventions at multiple points in the process of growing and packing produce to reduce the risk of enteric virus contamination and improve food safety during fruit and vegetable production.  相似文献   
115.
The purpose of this paper was to contribute to understanding of the crucial role of emotion in work motivation by testing a conceptual model developed by Seo, Barrett, and Bartunek (2004) that predicted the impacts of core affect on three behavioral outcomes of work motivation, generative-defensive orientation, effort, and persistence. We tested the model using an Internet-based investment simulation combined with an experience sampling procedure. Consistent with the predictions of the model, pleasantness was positively related to all three of the predicted indices. For the most part, these effects occurred indirectly via its relationships with expectancy, valence, and progress judgment components. Also as predicted by the model, activation was directly and positively related to effort.  相似文献   
116.
Environmental Geochemistry and Health - Geochemical modeling has been employed in several fields of science and engineering in recent years. This review seeks to provide an overview of case studies...  相似文献   
117.
Over the past few years, antibiotics have been considered emerging pollutants due to their continuous input and persistence in the aquatic ecosystem even at low concentrations. They have been detected worldwide in environmental matrices, indicating their ineffective removal from water and wastewater using conventional treatment methods. To prevent this contamination, several processes to degrade/remove antibiotics have been studied. This review addresses the current state of knowledge concerning the input sources, occurrence and mainly the degradation and removal processes applied to a specific class of micropollutants, the antibiotics. In this paper, different remediation techniques were evaluated and compared, such as conventional techniques (biological processes, filtration, coagulation, flocculation and sedimentation), advanced oxidation processes (AOPs), adsorption, membrane processes and combined methods. In this study, it was found that ozonation, Fenton/photo-Fenton and semiconductor photocatalysis were the most tested methodologies. Combined processes seem to be the best solution for the treatment of effluents containing antibiotics, especially those using renewable energy and by-products materials.  相似文献   
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The area of Cabedelo sand spit, located at the mouth of Douro River estuary (Porto, Portugal), reduced in recent decades. In order to study its evolution and also the impact of two breakwaters built to fix the river entrance, a dataset from 23 trimestral surveys using differential GPS techniques, conducted between 2001 and 2007, were considered. A time-series analysis and the estimation of relationships between Cabedelo spit area and several hydrodynamic parameters through statistical techniques were performed in order to determine which parameters have more influence in the Cabedelo spit behavior. From the time-series analysis a seasonal tendency is visible, with the lower values occurring in December and the higher values occurring in July. The estimation of a relationship between Cabedelo spit area and several independent variables reached better results when the dataset was divided in Part A (before the beginning of breakwaters construction) and Part B (during the breakwaters construction). An analysis of the morphological evolution of Cabedelo spit shoreline was also performed: (1) a simple analysis of retreat and accretion rates data with a geographical information system and (2) a more exhaustive analysis were performed using Empirical Orthogonal Functions (EOFs). The Cabedelo spit shoreline erosion occurs mostly on the West and North side, and the accretion mostly occurs in the area protected by the South breakwater. During the breakwater’s construction, the Cabedelo spit shoreline presented high retreat rates, with a mean value greater than 100 m. In terms of spatial variance (EOFs analysis), when the dataset was divided in two parts, the first Principal Component (PC) represents 60.10 % and 89.86 % of the mean squared value of the data, for Part A and Part B, respectively. As proved, the breakwaters would tend to stabilize the coastline leading to a higher first PC value after breakwaters construction (Part B).  相似文献   
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