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1.
In recent years the measurement of mold spore concentrations in working environments where workers spend long periods of time has acquired considerable importance because of the diffusion of diseases caused by fungi. On this basis, the aim of the research was to evaluate the level of environmental fungal pollution and contamination by mites in three factories producing seasoned foods, i.e., hams, sausages and cheeses. We also studied the occurrence of fungal species in the upper respiratory tract of workers operating in the washing and brushing areas, which was compared with the environmental concentrations in these areas, where contamination with fungal spores was visibly high. The results showed high and widespread fungal pollution in most of the working environments sampled and a significant presence of the same species in the upper respiratory tract of the workers. The data obtained indicate that the environments sampled can constitute a possible health risk factor for workers.  相似文献   
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Lethal and teratogenic potentials of carbon nanoparticles (CNPs) in their amorphous form were investigated by the standardized Frog Embryo Teratogenesis Assay-Xenopus (FETAX), a 96-h in vitro whole-embryo toxicity test based on the amphibian Xenopus laevis. Embryos were acutely exposed to 1, 10, 100 and 500 mg/L CNP suspensions and evaluated for lethality, malformations and growth inhibition. Larvae were processed for histological and ultrastructural analyses to detect the main affected organs, to look for specific lesions at the subcellular level and to image and track CNPs into tissues. Only the highest CNP suspension resulted in being embryolethal for X. laevis larvae, while malformed larva percentages significantly differed from controls starting from 100 mg/L. The stomach and gut were the preferential CNP accumulation sites, on the contrary, the digestive epithelium remained intact. The analyses showed the presence of isolated nanoparticles and/or aggregates in different secondary target organs. CNPs were found in circulating erythrocytes. The research confirms the good tolerance of X. laevis towards pure elemental carbon in its nanoparticulate amorphous form, but highlights the possibility of CNP transfer toward all body areas.  相似文献   
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This paper deals with the use of Kriging metamodels in multi-objective engineering design optimization. The metamodel management issue to find the tradeoff between accuracy and efficiency is addressed. A comparative analysis of different strategies is conducted for a case study devoted to the design of a component of the injection system for Compressed Natural Gas (CNG) engines. The computational results are reported and analyzed for a performance assessment conducted with a data envelopment analysis approach.  相似文献   
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An agile and environmentally conscious manufacturing paradigm refers to the ability to reconfigure a flexible system quickly, economically, and environmentally responsibly. In modern manufacturing enterprises, e-supply chains integrate Internet and web-based electronic market and are promising systems to achieve agility. A key issue in the strategic logistic planning of integrated e-supply chains (IESCs) is the configuration of the partner network. This paper proposes a single- and multiobjective optimization model to configure the network of IESCs. Considering an Internet-based distributed manufacturing system composed of different stages connected by material and information links, a procedure is presented to select the appropriate links. A set of performance indices is associated with the network links. Single-criterion and multicriteria optimization models are presented under structural constraint definitions. The integer linear programming (ILP) problem solution provides different network structures that allow to improve supply chain (SC) flexibility, agility, and environmental performance in the design process. The proposed optimization strategy is applied to two case studies describing two networks for desktop computer production.  相似文献   
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The activity of the autonomic nervous system is noninvasively studied by means of autoregressive (AR) frequency analysis of the heart-rate variability (HRV) signal. Some methods of noise rejection and robustness for AR recursive identification are presented that make on-line frequency analysis of the heart-rate variability signal more reliable. The performance of the algorithms is first tested through simulations, and then results obtained on real data during ischemic episodes are presented  相似文献   
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A highly sensitive radiochemical neutron activation method for the determination of all rare-earth elements (REE) in NBS biological reference materials is described. The materials are irradiated, dissolved in HF/HCl solutions, mixed with scandium and REE carriers (except La, Pr, Nd, Dy, Er), and the resulting solutions evaporated to dryness. The residues are dissolved in HCl and the REE precipitated as fluorides on addition of HF/NH4F solutions. The REE fluorides were collected, dissolved in a nitric/boric acid solution and the radioactivity of the resulting solutions determined by gamma spectrometry. The concentrations of REE in the NBS SRM Spinach, Orchard Leaves, Pine Needles, and Bovine Liver were found to be in the ng/g to microgram/g range. The relative standard deviations are approximately 8%. The results agreed, within experimental errors, with literature values. The distribution patterns of REE in the NBS materials relative to chondritic meteorites resemble the patterns for geological materials.  相似文献   
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Following the first report of avian Giardia infection in Australia, isolates of the parasite recovered from naturally infected straw-necked ibis (Theskiornis spinicollis) were characterized using median body morphology, scanning electron microscopy, multilocus enzyme electrophoresis, random amplified polymorphic DNA (RAPD), and small subunit ribosomal RNA (SSU-rRNA) analyses. Results were compared with Giardia from other birds and mammals, and the extent of genetic diversity between a range of ibis isolates collected in Western Australia was determined. The ibis isolates of Giardia were genetically relatively homogeneous, which is in contrast to the extensive genetic heterogeneity often displayed by mammalian Giardia isolates. Morphologically, Giardia from ibis were similar to Giardia ardeae although they differed genetically and by the fact that the ibis isolates could not be established in in vitro culture. Sequence data of the DNA coding for the SSU-rRNA found a 96% homology between the ibis isolates from Western Australia and G. ardeae, suggesting that they represent distinct strains of the same species. In contrast, the ibis isolates were genetically and morphologically very different than Giardia duodenalis and Giardia muris from mammals.  相似文献   
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