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921.
An integrated approach combining classic and molecular microbiological methods, “in vitro” bioremediation assays and groundwater numerical modeling, has been established to identify optimized solutions for remediating aquifers contaminated with organic pollutants. Bacteria have been isolated from an aquifer contaminated with toluene and methyl tert‐butyl ether (MTBE), selected for their growth with contaminants as a sole carbon source and identified through 16S rDNA partial sequencing. Successive biodegradation laboratory tests have been performed to determine which chemical conditions were more appropriate for the isolated bacteria to more efficiently oxidize toluene and MTBE. A groundwater model was created using FEFLOW code first to determine the movement of the plume front and second to simulate the impact of the biodegradation processes along the groundwater flow directions based on the bioremediation rates obtained in the laboratory. The results show that this innovative and interdisciplinary model can be used to assist in developing monitoring and remediation plans for cleaning up complex contaminated groundwater sites. This approach successfully combines the identification of the optimum biogeochemical conditions for bacterial biodegradation to occur with the predictability of the development of the process over time, ensuring decisive support in the management of contaminated sites. ©2016 Wiley Periodicals, Inc.  相似文献   
922.
The production of bioplastics directly from wheat flour has been demonstrated to be reliable, but scarce knowledge is available on how flour characteristics may affect the performance of thermoplastic films. In this work, we first established the most suitable recipe and process for the production of extruded films and then we used eight single-cultivar wheat flours with different baking technological properties to assess how they affect the mechanical properties of thermoplastic films. The results have shown that flours from soft grain cultivars offered more rigid and deformable films than flours from hard grain cultivars. For similar hardness, the alveographic P/L ratio of the dough was inversely related to rigidity and directly related to deformability of plastic films, while the deformation energy of the dough (W) played a role only for great differences of it. The subsequent fabrication of blends between each of the flours that yielded the best film properties and polycaprolactone (PCL) at different proportions indicated that a wheat flour/PCL ratio (TWF/PCL) of 75/25 offered the most suitable films for further application. Our results are likely to be useful for improving the plasticization of flour, in that selection of wheat flours could be tailored on the properties desired for the bioplastic films.  相似文献   
923.
Torque teno viruses (TTV) are small DNA viruses widespread among humans and pigs. The clinical significance of TTV infections in either humans or pigs is uncertain. In fact, TTV viremia is highly prevalent in patients with different pathologies, but it can also be frequently observed in healthy subjects. Virus infection in pigs is considered a putative cofactor in several diseases; despite being detected frequently in healthy animals, its role still remains unknown. The present study aimed to investigate the presence of Torque teno sus virus (TTSuV) in 62 bile samples collected from pigs at slaughterhouse and in 36 fresh pork liver sausages bought at point of sale. Quantitative Real-Time PCR, confirmed that 19.4 and 58.3 % of bile and sausage samples tested positive for TTSuV, respectively. The mean viral load was established as 5.6 × 104 GE/µl for bile and 7.16 × 103 GE/g for sausages. TTSuV nucleotide sequence analysis confirmed a wide heterogeneity among the circulating TTSuV strains, which included both TTSuV1 and TTSuV2.  相似文献   
924.
In the Russian Arctic, nature protection is important to preserve valuable ecosystems and indigenous lifestyles against the rapidly expanding oil and gas activities. In this regard, zoning legitimately balances influential stakeholders versus weak ones, and can leverage stakeholders to exercise their rights. This study explores how various stakeholders employ zoning in the Numto Nature Park in the oil-rich Russian Khanty-Mansi Autonomous Okrug–Yugra to advance their interests and how they use scientific information to achieve this. Through stakeholder interviews, analysis of electronic media and literature review, we conclude that a participatory and science-based zoning exercise stimulates the necessary deliberation. However, legal ambiguity, deficient law implementation and informal practices limit the zoning's potential to balance stakeholders’ interests. All the stakeholders calculatingly used scientific information to legitimize their own ambitions, activities and claims. Hence, zoning and the underlying information claims should be interpreted as both a resource and a battleground in nature-use conflicts.  相似文献   
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Journal of Material Cycles and Waste Management - The massive amount of plastic production inevitably leads to huge levels of pollution and, consequently, is threatening the environment and...  相似文献   
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929.
Citizen science has been gaining momentum in the United States and Europe, where citizens are literate and often interested in science. However, in developing countries, which have a dire need for environmental data, such programs are slow to emerge, despite the large and untapped human resources in close proximity to areas of high biodiversity and poorly known floras and faunas. Thus, we propose that the parataxonomist and paraecologist approach, which originates from citizen‐based science, is well suited to rural areas in developing countries. Being a paraecologist or a parataxonomist is a vocation and entails full‐time employment underpinned by extensive training, whereas citizen science involves the temporary engagement of volunteers. Both approaches have their merits depending on the context and objectives of the research. We examined 4 ongoing paraecologist or parataxonomist programs in Costa Rica, India, Papua New Guinea, and southern Africa and compared their origins, long‐term objectives, implementation strategies, activities, key challenges, achievements, and implications for resident communities. The programs supported ongoing research on biodiversity assessment, monitoring, and management, and participants engaged in non‐academic capacity development in these fields. The programs in Southern Africa related to specific projects, whereas the programs in Costa Rica, India, and Papua New Guinea were designed for the long term, provided sufficient funding was available. The main focus of the paraecologists’ and parataxonomists’ activities ranged from collection and processing of specimens (Costa Rica and Papua New Guinea) or of socioeconomic and natural science data (India and Southern Africa) to communication between scientists and residents (India and Southern Africa). As members of both the local land user and research communities, paraecologists and parataxonomists can greatly improve the flow of biodiversity information to all users, from local stakeholders to international academia.  相似文献   
930.
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