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131.
An observational study was designed to assess the bioaccumulation of polychlorodibenzodioxins (PCDD) and polychlorodibenzofurans (PCDF), dioxin-like polychlorobiphenyls (DL-PCB), and 13 selected polybromodiphenylethers (PBDE) in autochthonous pigs reared in the Nebrodi Park of Sicily (Italy). Perirenal fat and liver samples were drawn from animals representative of three different outdoor farming systems and from wild pigs and then analyzed for the chemicals mentioned previously. The highest concentrations of PCDD + PCDF and DL-PCB were detected in the fat (0.45 and 0.35 pg World Health Organization toxicity equivalents [WHO-TE] per g of fat base [FB], respectively) and livers (12.7 and 3.28 pg WHO-TE per g FB) of the wild group, whereas the free-ranging group showed the lowest levels (0.05 and 0.03 pg WHO-TE per g FB in fat and 0.78 and 0.27 pg WHO-TE per g FB in livers). The sum of PBDE congeners was highest in wild pigs (0.52 ng/g FB in fat and 5.64 ng/g FB in livers) and lowest in the farmed group (0.14 ng/g FB in fat and 0.28 ng/g FB in livers). The contamination levels in fat and livers of outdoor pigs had mean concentration values lower than those levels reported for intensively indoor-farmed animals. In wild pigs, bioaccumulation was associated with their free grazing in areas characterized by bush fires. The results of this study aid to emphasize the quality of the environment as a factor to guarantee food safety in typical processed pig meat products, specifically from outdoor and extensive Nebrodi farming systems.  相似文献   
132.
This paper presents SUVEHP (speed up of video enhancement based on human perception), a human perception-based model oriented to reduce the computational time of digital video restoration. In particular, two specific hypothesis tests able to classify degraded frame regions are proposed. Classification is performed in agreement with regions visual significance in order to enable or inhibit motion compensated enhancement. The level of the proposed hypothesis tests is theoretically assessed. Moreover, extensive experimental results on video sequences affected by additive Gaussian noise show that SUVEHP speeds up some standard motion compensated denoisers up to 60%, preserving or even slightly increasing both the objective and subjective visual quality of the restored sequences.  相似文献   
133.
Twenty-six patients with relapsed or refractory Hodgkin's disease (HD) were treated with an intensive salvage regimen combining ifosfamide (3000 mg/m2/d, days 1-4 through continuous intravenous infusion) and vinorelbine (25 mg/m2, i.v. days 1 and 5) with mesna uroprotection and G-CSF support. Courses were given at 3-week intervals. Ten patients achieved a complete and 10 patients a partial response, yielding an overall response rate of 77%. The main toxic effect was neutropenia and the combination was well tolerated.  相似文献   
134.
A binding matrix containing calcium silicate beta-2CaO.SiO(2) and sulphoaluminate 4CaO.3Al(2)O(3).SO(3), and CaSO(4) that gives calcium silicate and trisulphoaluminate hydrates upon hydration has been used for the stabilization of a solid waste from a galvanic treatment process. The waste is to be disposed of in a hazardous wastes landfill to prevent the risk of cadmium, chromium and nickel release. Anhydrous calcium silicate and sulphoaluminate of the binder have been synthesized using a mixture containing powdered tuff in addition to bauxite and calcium carbonate and sulphate. Powdered tuff is quarry dust and is, as such, a true residue. Experiments have been carried out with mixtures containing up to 60% waste and have been addressed towards the environmental and technological assessment of the effectiveness of the stabilization process. Specifically, the study has been carried out taking into account requirements from three different points of view, that is the influence of the waste on the hydration process and on the technological properties of the stabilized products, the leaching behavior under some selected conditions and the effect of the leaching medium on the binding matrix in the stabilized system.  相似文献   
135.
Italy produces approximately 4,520,000 tons of pasta annually, which is about 67% of its total productive potential. As factories need electric and thermal energy simultaneously, combined heat and power (CHP) systems are the most suitable. This paper describes a feasibility study of a CHP plant in a pasta factory in Italy while analyzing energy saving and environmental benefits. Commercially available CHP systems suitable for the power range of energy demand in pasta production use reciprocating engines or gas turbines. This study demonstrates how their use can reduce both energy costs and CO2 equivalent greenhouse gas emission in the environment. An economic analysis was performed following the methodology set out by Italian National Agency for Technology, Energy and Environment (ENEA) based on a discounted cash flow (DCF) method called “Valore Attuale Netto” (VAN), which uses a cash flow based on the saving of energy when using different energy processes.  相似文献   
136.
A Fenton‐like process, involving oxidation and coagulation, was evaluated for the removal of odorous compounds and treatment of a pulp and paper wastewater. The main parameters that govern the complex reactive system [pH and Fe(III) and hydrogen peroxide concentrations] were studied. Concentrations of Fe(III) between 100 and 1000 mg L?1 and of H2O2 between 0 and 2000 mg L?1 were chosen. The main mechanism for color removal was coagulation. The maximum COD, color and aromatic compound removals were 75, 98 and 95%, respectively, under optimal operating conditions ([Fe(III)] = 400 mg L?1; [H2O2] = 500–1000 mg L?1; pH = 2.5; followed by coagulation at pH 5.0). The biodegradability of the wastewater treated increased from 0.4 to 0.7 under optimal conditions and no residual hydrogen peroxide was found after treatment. However, partially or non‐oxidized compounds present in the treated wastewater presented higher acute toxicity to Artemia salina than the untreated wastewater. Based on the optimum conditions, pilot‐scale experiments were conducted and revealed a high efficiency in relation to the mineralization of organic compounds. Terpenes [(1S)‐α‐pinene, β‐pinene, (1R)‐α‐pinene and limonene] were identified in the wastewater and were completely eliminated by the Fenton‐like treatment. Copyright © 2006 Society of Chemical Industry  相似文献   
137.
The chemical transformations taking place when poly(ethylene terephthalate) (PET) or poly(ethylene naphthalate) (PEN) are blended in the melt with different low molar mass substances containing hydroxyl, carboxyl, or amine functional groups have been investigated as models of the transreactions, undergone by the polyesters in reactive blending operations. The polyester molecular weight changes caused by the alcoholysis, acidolysis, aminolysis, and esterolysis reactions have been monitored by torque‐rheometry, using a Brabender Plasticorder static mixer. The degradation of the polyesters by hydrolysis was also studied, under similar conditions, by the addition of a water‐releasing substance (wet polyamide‐6), and was shown to occur quite rapidly, although most of the added water was lost by flash vaporization caused by the high temperature of the polyester melt. It has been shown that the rate constants of the reactions leading to breakage of the inner ester bonds of the polyester macromolecules decrease in the following order: aminolysis (with aliphatic amines, either primary and secondary) > alcoholysis (with aliphatic alcohols) ≈ hydrolysis > acidolysis (with aromatic acids) ≥ acidolysis (with aliphatic acids) ? aminolysis (with aromatic amines) > alcoholysis (with phenols) ? esterolysis. POLYM. ENG. SCI. 46:139–152, 2006. © 2005 Society of Plastics Engineers  相似文献   
138.
BACKGROUND: These is no consensus in the literature regarding the differentiation of conjunctival goblet cells in vertebrates. METHOD: The conjunctival epithelium of the chick was studied before and after hatching in order to demonstrate the morphological evolution of the goblet cells. The entire conjunctiva was processed for light microscopy either on semithin sections stained with toluidine blue-pironine or on traditional sections stained with Alcian blue pH 2.5-PAS. RESULTS: It was possible to demonstrate that goblet cells underwent remarkable changes in their secretory activity. At 12 h after hatching, isolated Alcian blue-positive cells were present in the fornix. At 24 h after hatching, cells positive for both Alcian blue and PAS were scattered among epithelial cells. Two days after hatching, cells which reacted positively only to PAS were also present. CONCLUSION: It is suggested that the differentiation of conjunctival goblet cells occurs first in the fornix, probably due to the particular vascular environment of this region, and then spreads all over the conjunctiva.  相似文献   
139.
This study was designed to determine whether the maintenance of higher than usual patient-specific heparin concentrations during cardiopulmonary bypass (CPB) was associated with more effective suppression of hemostasis system activation. Thirty-one patients scheduled for repeat cardiac surgery or combined procedures (i.e., coronary revascularization + valve repair/replacement) were consented and enrolled in this study. All patients received porcine heparin and protamine and were randomly assigned to monitoring of anticoagulation by either celite ACT alone (Control, n = 16) or by kaolin ACT combined with on-site measurements of whole blood heparin concentration (Intervention, n = 15). Blood specimens collected before administration of heparin, before weaning from CPB and after administration of protamine were analyzed with a battery of coagulation assays. Patients in the intervention cohort received appreciably greater heparin doses than control patients, resulting in higher anti-Xa heparin levels at the end of CPB. Fibrinopeptide A and D-dimer levels were higher in the control group before discontinuation of CPB. Percent decrease during CPB were greater in the control group for factors V and VIII, fibrinogen and antithrombin III. Percent decrease in complement 3 was greater in the control group after protamine and bleeding times measured in the Intensive Care Unit were significantly more prolonged in this group. Maintenance of higher patient-specific heparin concentrations during CPB more effectively suppresses excessive hemostatic system activation than do standard heparin doses chosen based on measurement of ACT. These findings may explain, at least in part, the significant reduction in perioperative blood loss and blood product use when higher heparin concentrations are maintained.  相似文献   
140.
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