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101.
Relationships between organizational justice and well-being are traditionally investigated at the individual level. This article extends previous efforts by testing such relationships at the work-unit level. Three corridors of influence were examined. First, the level (work units' average scores) of justice is related to the level of burnout. Second, justice climate strength (level of agreement among work-unit members) moderates the predictability of the level of burnout. Third, justice strength is related to burnout strength. The authors interviewed 324 contact employees from 108 work units in 59 service organizations. Findings showed the predominance of interactional justice over distributive and procedural justice in all 3 corridors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
A combined refrigeration system consisting of ozone and flow ice was evaluated for the sacrifice, cooling and chilled storage of continental trout. The batch processed in ozonised flow ice exhibited significant ( P  < 0.05) reductions (0.97 and 1.51 log CFU cm−2) in skin aerobes and psychrotrophs on days 6 and 9, respectively, and significant ( P  < 0.05) reductions (0.94 log CFU g−1 and 0.96 log CFU g−1) in aerobes, and proteolytic bacteria in muscle on day 13. A significant ( P  < 0.05) inhibition of TMA-N formation after 9 days was also observed, with an average reduction of 28.4% along the storage period, Slight reductions in autolytic breakdown mechanisms were also observed in the ozonised batch, a maximum reduction of 14.82% being reached on day 13. The microbial and biochemical changes were well correlated with the sensory evaluation, which revealed relevant differences between the batches on day 13 and a shelf life extension of the ozonised batch up to day 16.  相似文献   
103.
OBJECTIVE: Determine the cost and effectiveness of partner notification for human immunodeficiency virus (HIV) infection. METHODS: Persons testing HIV positive in three areas were randomly assigned one of four approaches to partner notification. Analysis plans changed because disease intervention specialists notified many partners from the patient referral group. We dropped the patient referral group and combined the others to assess the cost and effectiveness of provider referral. RESULTS: The 1,070 patients reported 8,633 partners. Of those 1,035 were located via record search or in person. A previous positive test was reported by 248 partners. Of the 787 others, 560 were tested: 438 were HIV negative and 122 were newly identified as HIV positive. The intervention specialist's time totaled 197 minutes per index patient. The cost of the intervention specialist's time, travel, and overhead was $268,425: $251 per index patient, $427 per partner notified, or $2,200 per new HIV infection identified. No demographic characteristic of the index patient strongly predicted the likelihood of finding an infected partner. CONCLUSION: We could not compare the effectiveness of different partner notification approaches because of frequent crossover between randomized groups. The cost of partner notification can be compared with other approaches to acquired immunodeficiency syndrome prevention, but the benefits are not easily measured. We do not know the number of HIV cases prevented or the value of fulfilling the ethical obligation to warn partners of a potential threat to their health.  相似文献   
104.
Gallic acid (3,4,5-trihydroxybenzoic acid) is a major pollutant present in the wastewater generated in the boiling cork process, as well as in other wastewaters from food manufacturing industries. Its decay in aqueous solutions has been studied by the action of several oxidation systems: monochromatic UV radiation alone and combined with hydrogen peroxide, Fenton's reagent and the combination Fenton's reagent with UV radiation (photo-Fenton system). The influence of the pH is discussed and the quantum yields are determined in the UV radiation system. Also, the influence of operating variables (initial concentrations of H2O2 and Fe(II), and pH) is established in the Fenton's reaction. The apparent pseudo-first-order rate constants are evaluated in all the experiments conducted in order to compare the efficiency of each one of the processes. Increases in the degradation levels of gallic acid are obtained in the combined processes in relation to the single UV radiation system, due to reactions of the very reactive OH*. These improvements are determined in every process by calculating the partial contribution to the overall decomposition rate of the radical pathways. For the oxidant concentrations applied, the most effective process in removing gallic acid was found to be the photo-Fenton system. The rate constant for the reaction of gallic acid with OH was also determined by means of a competition kinetics model, being its value 11.0+/-0.1 x 10(9)l mol(-1)s(-1).  相似文献   
105.
Nowadays there is an increasing number of recombinant enzymes made available to industry. Before replacing the use of natural enzymes with their cognate recombinant counterparts, one important issue to address is their actual equivalence. For a given recombinant proteolytic enzyme, its equivalence can be investigated by comparing its cleavage specificity with that obtained from the natural enzyme. This is mostly done by analyzing the fragments (i.e., peptidic map) attained after enzymatic digestion of a given protein used as substrate. The peptidic maps obtained are typically characterized using separation techniques together with MS and MS/MS systems. However, these procedures are known to be difficult and labor-intensive. In this work, the combined use of a theoretical model that relates electrophoretic behavior of peptides to their sequence together with capillary electrophoresis-mass spectrometry (CE-MS) is proposed to characterize in a very fast and simple way the cleavage specificity of new recombinant enzymes. Namely, the effectiveness of this procedure is demonstrated by analyzing in few minutes the fragments obtained from a protein hydrolysated using recombinant and natural pepsin A. The usefulness of this strategy is further corroborated by CE-MS/MS. The proposed procedure is applicable in many other proteomic studies involving CE-MS of peptides.  相似文献   
106.
The aim of this study was to review prior studies that have evaluated the effects of cooking techniques on polyphenol levels and antioxidant activity in vegetables and to release a meta-analysis of the findings. Meta-analysis with a random effect model was conducted using the weighted response ratios (R*) that were calculated for each experiment. Baking (R* = 0.51), blanching (R* = 0.94), boiling (R* = 0.62), microwaving (R* = 0.54) and pressure cooking (R* = 0.47) techniques precipitated significant reductions in the polyphenol levels. Significant decreases in the antioxidant activity levels were noted after baking (R* = 0.45) and boiling (R* = 0.76), while significant increases were observed after frying (R* = 2.26) and steaming (R* = 1.52).  相似文献   
107.
Thirty-two lambs were finished on a total mixed ration (TMR) pelleted alone (00SS) or including sunflower soap stock (SS): 15SS (15 g SS per kg TMR), 30SS (30 g SS per kg TMR) and 60SS (60 g SS per kg TMR). Lambs (8 per group) were slaughtered at 27 kg live weight. Colour evolution, lipid oxidation, microbial growth and detection of diarrhoeagenic Escherichia coli were studied in meat samples. SS in the diet reduced meat lipid oxidation (< 0.05), but had no significant effect (P > 0.05) on the cholesterol oxidation products. Meat from 60SS and control animals (00SS) revealed greater discoloration (< 0.05) than 15SS. SS supplementation did not affect the microbiological populations, whereas high doses of SS seemed to increase the proliferation of diarrhoeagenic E. coli on day 14 (< 0.10). These results suggest that the rate of SS inclusion in the diet of fattening lambs should not be above 15 g SS per kg TMR.  相似文献   
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110.
The high temperature antioxidant efficiency of α‐tocopherol, α‐tocotrienol and a mixture of both on hazelnut oil were evaluated. Crude hazelnut oil (HZO), crude hazelnut oil treated with alumina (THZO), as well as three samples of THZO to which 150 mg kg?1 of α‐tocopherol, 140 mg kg?1 of α‐tocotrienol or a mixture containing 70 mg kg?1 of α‐tocopherol and 70 mg kg?1 of α‐tocotrienol, were added and submitted to thermal treatment at 180°C for 18 h. The addition of tocols to THZO decreased the formation of polar compounds and increased its oxidative stability in all the systems studied. However, α‐tocopherol showed a higher antioxidant capacity than α‐tocotrienol at high temperature. In addition, α‐tocotrienol showed a more rapid degradation rate than α‐tocopherol under the conditions studied. Copyright © 2004 Society of Chemical Industry  相似文献   
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