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221.
222.
Concentrations of Cd and As were determined in organs and tissues (muscle, heart, kidney, lung and liver) of four cetacean species (Stenella coeruleoalba, Truncatus truncatus, Grampus griseus and Ziphius cavirostris) stranded along the Italian coasts during the period 2000-2009. Significant differences were found between Cd concentrations in the different analysed tissues. Particularly, the kidney shows the highest concentrations of Cd in all analysed specimens, followed by the liver. No systematic or statistically significant difference in As concentrations was found in the analysed tissues. Considerable differences of Cd and As values in samples from different geographical areas (Sicily Channel, Adriatic Sea and Tyrrhenian Sea) were found, with the highest values measured in samples from the Sicily Channel. This basically suggests that anthropogenic and natural sources significantly affect Cd and As content in cetaceans.  相似文献   
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224.
Rural change in Cambodia manifests itself in rapidly declining land availability for the smallholder sector, posing the question of how farmers may be able to deal with limited access to land. In this paper, we discuss with a case study village and household livelihood strategies of smallholders currently operating under land-constrained conditions. Based on an integrated assessment of a smallholder village in Kampot province, we illustrate in quantitative terms how land shortage is creating problems of surplus generation and liquidity issues in monetary and non-monetary flows. At the household level, livelihood diversification based on the involvement of productive resources other than land may play an increasing role, particularly in the future, when levels of land shortage may increase. At the village level, smallholder may respond through institutional innovation, in particular through the establishment of a community banking system and a paddy rice bank to provide money and rice credits to overcome transitory shortages and to cover investment costs for additional productive resources. Thus, in this case, we observe the emergence of new patterns of livelihood in rural areas, based on the integration of non-land-based economic activities and new institutional settings.  相似文献   
225.
Sensitized P25 TiO2 was prepared by wet impregnation with a home-prepared perylene dye, i.e., N,N′-bis(2-(1-piperazino)ethyl)-3,4,9,10-perylene-tetracarboxylic acid diimide dichloride (PZPER). Energy levels of PZPER were found to be compatible with those of TiO2 allowing fast electron transfer. The obtained catalyst has been characterized and used in the gas-phase partial oxidation of aliphatic primary and secondary alcohols, i.e., methanol, ethanol, and 2-propanol. The reaction was carried out under cut-off (λ?>?400 nm) simulated solar radiation in O2 atmosphere. The perylene derivative allowed a good absorbance of visible radiation thanks to its low optical energy gap (2.6 eV) which was evaluated by cyclic voltammetry. The optimal organic sensitizing amount was found to be 5.6 % w/w in terms of yield in carbonyl derivatives. Moreover, no change in reactivity/selectivity was observed after 10-h irradiation thus confirming the catalyst stability. Yields into formaldehyde, acetaldehyde, and acetone were 67, 70, and 96 %, respectively. No significant amounts of organic byproducts were detected but for methanol oxidation, whereas a minor amount of the substrate degraded to CO2.  相似文献   
226.
ABSTRACT

This paper demonstrates statistical methods that estimate measurement error from available industrial hygiene data. Errors in measuring a continuous exposure variable may arise when all individuals in a work area are assigned the same exposure. An example is when the mean of exposure measurements obtained on a sample of individuals is assigned to all workers with similar jobs. This may lead to inaccurate point and interval estimates in exposure-response modeling. A method of simulating the distribution of true (i.e., unobserved) individual exposures is described in order to estimate the mean and variance of measurement error. The minimum variance unbiased estimator approximates the mean of lognormally distributed exposure measurements. The distribution of true individual exposures is approximated by the distribution of simulated estimates of mean exposure. The methodology is illustrated by exposure data from work areas manufacturing refractory ceramic fiber (RCF) and RCF products. Results show that exposure is slightly underestimated in work areas with between 25 and 113 exposure measurements; measurement error variance averages about 1.3% of the total variance.  相似文献   
227.
Companies need to follow environmental laws as they affect their manufacturing systems, waste handling, and the management of soil on their properties to ensure that their properties are either improved or altered as little as possible. Thus, the objective of this study was to evaluate the use of energy dispersive X‐ray fluorescence spectrometry (EDXRF) to determine the concentrations of elements present in the soil at a manufacturer of products based on fiberglass where wastes from production activities have been deposited on the property.  相似文献   
228.
Although the 2Rs (reduce and reuse) are considered high-priority approaches, there has not been enough quantitative research on effective 2R management. The purpose of this paper is to provide information obtained through the International Workshop in Kyoto, Japan, on 11–13 November 2015, which included invited experts and researchers in several countries who were in charge of 3R policies, and an additional review of 245 previous studies. It was found that, regarding policy development, the decoupling between environmental pressures and economy growth was recognized as an essential step towards a sustainable society. 3R and resource management policies, including waste prevention, will play a crucial role. Approaches using material/substance flow analyses have become sophisticated enough to describe the fate of resources and/or hazardous substances based on human activity and the environment, including the final sink. Life-cycle assessment has also been developed to evaluate waste prevention activities. Regarding target products for waste prevention, food loss is one of the waste fractions with the highest priority because its countermeasures have significant upstream and downstream effects. Persistent organic pollutants and hazardous compounds should also be taken into account in the situation where recycling activities are globally widespread for the promotion of a material-cycling society.  相似文献   
229.

Introduction  

Arsenic (As) can be removed from water via rhizofiltration using phytostabilizing plants. The aim of this study was to investigate the performance of Eleocharis macrostachya in constructed wetland prototypes, as well as the plant's arsenic mass retention and the distribution of As along the wetland flow gradient and the soil in the wetland mesocosmos.  相似文献   
230.
In this study the aflatoxin B(1) (AFB(1)) removal capacity, the tolerance to salivary and gastrointestinal conditions, autoaggregation and coaggregation with pathogenic bacteria of Saccharomyces cerevisiae strains isolated from broiler feces, were evaluated. Only four of twelve isolated strains were identified as Saccharomyces cerevisiae using molecular techniques. The results obtained in AFB(1) binding studies indicated that the amount of AFB(1) removed was both strain and mycotoxin-concentration dependent. Therefore, a theoretical model was applied in order to select the most efficient strain to remove AFB(1) in a wide range of mycotoxin concentration. The results indicated that S. cerevisiae 08 and S. cerevisiae 01 strains were the most efficient microorganisms in the mycotoxin removal. Viability on simulated salivary and gastrointestinal conditions was investigated and S. cerevisiae 08 strain showed the best results, achieving 98% of total survival whereas S. cerevisiae 01 reached only 75%. Autoaggregation and coaggregation assays showed S. cerevisiae 08 as the most appropriate strain, mainly because it was the unique strain able to coaggregate with the four bacterial pathogens assayed. Consequently, S. cerevisiae 08 is the best candidate for future in vivo studies useful to prevent aflatoxicosis. Further quantitative in vitro and in vivo studies are required to evaluate the real impact of yeast-binding activity on the bioavailability of AFB(1) in poultry. However, this study could be useful in selecting efficient strains in terms of AFB(1) binding and provide an important contribution to research into microorganisms with potential probiotic effects on the host.  相似文献   
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