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排序方式: 共有224条查询结果,搜索用时 31 毫秒
191.
Volpe Angela D’Arpa Stefania Del Moro Guido Rossetti Simona Tandoi Valter Uricchio Vito Felice 《Water, air, and soil pollution》2012,223(4):1773-1782
An environmentally friendly procedure suitable to restore a protected area was evaluated at laboratory scale. Soil contaminated
by high molecular weight (C > 10) aliphatic hydrocarbons and by chromium was withdrawn from the study site and a qualitative
study of soil hydrocarbon components was first performed in order to assess the potential source of contamination. To this
aim, a number of characteristic diagnostic ratios of hydrocarbon components were derived by processing chromatographic data,
and were used as indicators for distinguishing anthropogenic from natural hydrocarbons. Then, the efficiency of landfarming
for soil remediation was tested by comparing the effect of a few selected amendments and by monitoring the fate of chromium.
Soil microbial abundance and activity were also evaluated. Results showed that soil hydrocarbons were mainly of anthropogenic
origin and land treatment allowed effective degradation by native microbial populations even in the absence of amendments.
The investigated procedures had no effect on the mobilisation of chromium that remained in its stable form of Cr(III). Conventional
land treatment may therefore be an effective and safe procedure for the removal of hydrocarbons even in the presence of chromium,
and may be applied to areas where low-impact procedures are strictly required. 相似文献
192.
Buffy coat smear or Knott's test: which to choose for canine microfilaria screening in field studies?
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193.
Vichi S Pizzale L Conte LS Buxaderas S López-Tamames E 《Journal of agricultural and food chemistry》2003,51(22):6564-6571
Modifications of virgin olive oil subjected to accelerated storage were evaluated by HS-SPME analysis. To find a suitable marker of oxidative degradation, the volatile compounds showing variable concentration during the oxidative process have been identified and quantified by SPME coupled to GC-MS and GC-FID, respectively. The SPME analysis results were then compared with the parameters usually applied to assess the oxidative status of lipids, such as peroxide value, spectrophotometric absorbance, and loss of unsaturated fatty acids. Finally, the assessment of nonanal has been suggested as a marker of oxidative degradation. This rapid, inexpensive, and reliable method may allow screening of oils prior to testing by a panel of assessors. 相似文献
194.
D'Angelo S Cimmino A Raimo M Salvatore A Zappia V Galletti P 《Journal of agricultural and food chemistry》2007,55(24):9977-9985
Apple is among the most consumed fruits worldwide, and several studies suggest that apple polyphenols could play a role in the prevention of degenerative diseases. 'Annurca' apple fruit undergoes, after harvest, a typical reddening treatment to turn the apples' skin red, and it is noted for its high firmness. This paper reports the effect of reddening-ripening treatment on polyphenol concentration and antioxidant activity of both peel and flesh extracts. The in vitro antioxidant properties have been compared with the protective effect against the cytotoxic effects of reactive oxygen species using Caco-2 cells as model system. Pretreatment of cells with different polyphenolic apple extracts provides a remarkable protection against oxidative damage. This effect seems to be associated with the antioxidant activity of 'Annurca' apple polyphenolic compounds. The flesh has antioxidant properties comparable to those possessed by the peel. Neither the reddening nor the fruit conservation causes changes in the antioxidant properties possessed by this apple variety. The data indicate that polyphenolic compounds in 'Annurca' apples are relatively stable in the peel and also in the flesh; therefore, the health benefits of polyphenols should be maintained during long-term storage. Finally, a diet rich in apple antioxidants could exert a beneficial effect in the prevention of intestinal pathologies related to the production of reactive oxygen species. 相似文献
195.
Xavier Domene Stefania Mattana Wilson Ramírez Joan Colón Patrícia Jiménez Teresa Balanyà Josep M. Alcañiz Manel Bonmatí 《Journal of Soils and Sediments》2010,10(1):30-44
Background, aim, and scope
Mining activities disturb land and reduce its capacity to support a complete functional ecosystem. Reclamation activities in this case are not easy due to the large amount of soil required. This is why mining debris are usually used as surrogate of soil, despite their unsuitable physicochemical properties. However, these properties can be improved with the amendment using an organic source, usually sewage sludge. Nevertheless, the use of sludge might lead to impacts on soil and water ecosystems because of its physicochemical properties and pollutant content. The aim of this study is to assess the suitability of the use of mining debris amended with sewage sludge as practice for the reclamation of land degraded by limestone-quarrying activities. 相似文献196.
Stefania Astolfi Sabrina Zuchi Stefano Cesco Zeno Varanini Roberto Pinton 《Soil Science and Plant Nutrition》2013,59(7):1079-1083
Abstract Recent research has evidenced a relationship between Fe nutrition and S nutrition. Aim of the present work was to investigate the effect of Fe deficiency on the capacity of maize roots to take up and metabolize S. Maize (Zea mays L. cv. Cecilia) plants were grown for 10 d in nutrient solution (NS) with (+S) or without (?S) sulphate and Fe was added as FeIII-EDTA at 80 μm. After removing the extraplasmatic Fe pool, half of the plants of each treatment (+S and ?S) were transferred to a new Fe-free NS. Roots were collected 4 and 24 h from the beginning of Fe deprivation. Fe deprivation slightly increased root thiols content in both nutritive conditions (+S and ?S). ATP sulphurylase activity was enhanced by sulphur deprivation, but greatly depressed when Fe and S were both omitted from the nutrient solution. O-Acetylserine sulphydrylase activity was also enhanced by S deprivation; this activity was increased by Fe starvation in +S plants, while it was unaffected by Fe nutrition in ?S plants. S deprivation greatly increased uptake rates of 35SO4 2? (1.9 ± 0.1 vs. 5.2 ± 0.2 μmol g?1 root d.w. h?1); furthermore, Fe deficiency increased 35SO4 2? uptake rates by 11 and 55% in +S and ?S plants, respectively. Data show that Fe-deficiency in maize results in a higher ability to take up sulphate, while limiting the first step of S assimilation in S deprived plants. 相似文献
197.
Conducting sustainability impact assessments of forestry-wood chains: examples of ToSIA applications
Marcus Lindner Wendelin Werhahn-Mees Tommi Suominen Diana V?tter Sergey Zudin Matias Pekkanen Risto P?ivinen Martina Roubalova Petr Kneblik Franka Brüchert Erik Valinger Ludovic Guinard Stefania Pizzirani 《European Journal of Forest Research》2012,131(1):21-34
Within the EFORWOOD project, new methodological approaches to assess the sustainability impacts of forestry-wood chains (FWC) were developed by using indicators of environmental, social and economic relevance. This paper introduces and discusses the developed approach and the two main products developed in the EFORWOOD project: the Database Client and the Tool for Sustainability Impact Assessment (ToSIA), which hold, calculate and integrate the extensive information and data collected. Sustainability impact assessment (SIA) of FWCs is based on measuring and analysing environmental, economic and social indicators for all of the production processes along the value chain. The adoption of the method varies between applications and depends on the specification of the FWC in the assessment and what questions are studied. ToSIA is very flexible and can apply forest-, product-, industry- and consumer-defined perspectives. Each perspective influences the focus of the analysis and affects system boundaries. ToSIA can assess forest value chains in different geographical regions covering local, regional, national and up to the continental scale. Potential issues and scenarios can be analysed with the tool including, for example, the impacts of different forest policies on the sustainability of an FWC. This paper presents how ToSIA can be applied to solve such diverse problems and underlines this with examples from different case studies. Differences in chain set-up, system boundaries and data requirements are highlighted and experiences with the implementation of the sustainability impact assessment methods are discussed. The EFORWOOD case studies offer valuable reference data for future sustainability assessments. 相似文献
198.
199.
Manuela Mariotti Stefania Iametti Carola Cappa Patrizia Rasmussen Mara Lucisano 《Journal of Cereal Science》2011
Formation of a gluten protein network is fundamental for the texture and the overall quality of pasta. Replacement of the gluten network in gluten-free pasta is a major technological challenge, and the conventional technological processes have to be adapted to non-gluten formulations. The wide variety of raw materials and technologies used in the production of commercial gluten-free pasta stems from the – still on-going – search for solutions to these problems. The aim of this study was to evaluate the characteristics of different commercial gluten-free spaghetti currently available on the market, focusing on starch and protein organisation. Taking into account the chemical and biochemical properties of the samples, and their relationships to the physical characteristics of these products we looked at how some molecular properties relate to the final structure and quality of gluten-free pasta. Phenomena related to starch retrogradation were found to play a central role for the final texture of the products. At the same time, the origin of proteins included in the formulation was found to govern the protein–protein interactions, especially in those samples including proteins from different vegetable sources. 相似文献
200.
Abenavoli L Bardazzi G Cracolici F Quaranta C Santini G Graziosi S Polero L Leggio L Addolorato G 《Fitoterapia》2008,79(2):142-147