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31.
Examined the entailment model of attributions in close relationships (F. D. Fincham and T. N. Bradbury, 1987) using structural equation modeling. In this model, judgments of causality lead to judgments of responsibility, which in turn determine judgments of blame. The sample consisted of 206 married or cohabiting couples who completed the Conflict Rating Scale and the Dyadic Adjustment Scale. The path analysis conducted with LISREL VII supported the value of an entailment conceptualization for both self (women and men) and spouse attributions (men only). As hypothesized, for men the paths among causality, responsibility, blame, and marital adjustment confirmed the mediating role of responsibility and blame attributions. For women, small direct pathways leading to marital satisfaction were found, as well as 2 large indirect pathways specified by the entailment model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
The broad spectrum antimicrobial agents triclosan (TCS) and triclocarban (TCC) are widely used in many personal care products. Knowledge concerning the fate of these two compounds in different environmental matrices is scarce. In this study, the fate of TCS and TCC in soil following direct addition, or when residues were applied via either liquid municipal biosolids (LMB) or dewatered municipal biosolids (DMB) was investigated in laboratory dissipation experiments and under outdoor conditions using radioisotope methods. In laboratory incubations, 14C-TCC or 14C-TCS was added to microcosms containing a loam soil and the rate of 14CO2 accumulation and loss of solvent-extractable 14C were determined during incubation at 30 °C. Compared to when TCC or TCS was added directly to soil, both chemicals were mineralized more rapidly when applied in LMB, and both were mineralized more slowly when applied in DMB. The application matrix had no effect on the rate of removal of extractable residues. In field experiments, parent compounds were incorporated directly in soil, incorporated via LMB, or a single aggregate of amended DMB was applied to the soil surface. During the experiment soil temperatures ranged from 20 °C to 10 °C. Dissipation was much slower in the field than in the laboratory experiments. Removal of non-extractable residues was faster in the presence of LMB than the other treatments. Recovery of extractable and non-extractable residues suggested that there was little atmospheric loss of 14C. Triclocarban readily formed non-extractable residues with DMB whereas TCS did not. Overall, this study has identified that both the pathways and the kinetics of TCS and TCC dissipation in soil are different when the chemicals are carried in biosolids compared to when these chemicals are added directly to the soil.  相似文献   
33.
Municipal biosolids are a useful source of nutrients for crop production, and commonly used in agriculture. In this field study, we applied dewatered municipal biosolids at a commercial rate using broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 21 and 34 days following the application on 2 m2 microplots to evaluate surface runoff of various pharmaceuticals and personal care products (PPCPs), namely atenolol, carbamazepine, cotinine, caffeine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole, triclosan and triclocarban. There was little temporal coherence in the detection of PPCPs in runoff, various compounds being detected maximally on days 1, 3, 7 or 36. Maximum concentrations in runoff ranged from below detection limit (gemfibrozil) to 109.7 ng L− 1 (triclosan). Expressing the total mass exported as a percentage of that applied, some analytes revealed little transport potential (< 1% exported; triclocarban, triclosan, sulfamethoxazole, ibuprofen, naproxen and gemfibrozil) whereas others were readily exported (> 1% exported; acetaminophen, carbamazepine, caffeine, cotinine, atenolol). Those compounds with little transport potential had log Kow values of 3.18 or greater, whereas those that were readily mobilized had Kow values of 2.45 or less. Maximal concentrations of all analytes were below toxic concentrations using a variety of endpoints available in the literature. In summary, this study has quantified the transport potential in surface runoff of PPCPs from land receiving biosolids, identified that log Kow may be a determinant of runoff transport potential of these analytes, and found maximal concentrations of all chemicals tested to be below toxic concentrations using a variety of endpoints.  相似文献   
34.
Constitutive equations for sheet metals are important input data for the numerical simulation of forming processes. Their identification usually comes from uniaxial tensile tests at several orientations to the rolling direction and from equibiaxial tests. To characterize the kinematic part of the work hardening, strain path reversals are needed and different mechanical tests have been developed, such as tension-compression and simple shear. The aim of this work is to investigate the influence of the database used for identification, by using either bending-unbending or simple shear for strain path reversal. This study is performed both on an aluminum alloy and a TRIP steel. The presented results show that, for a limited strain range, the experiments are consistent.  相似文献   
35.
The heterogeneous interaction between nitromethane (NM), particles of nanoscale aluminum (38 and 80 nm diameter), and fumed silica is examined in terms of the deflagration and detonation characteristics. Burning rates are quantified as functions of pressure using an optical pressure vessel up to 14.2 MPa, while detonation structure is characterized in terms of failure diameter. Nitromethane is gelled using fumed silica (CAB‐O‐SIL®), as well as by the nanoaluminum particles themselves. Use of nanoaluminum particles with fumed silica slightly increases burning rates compared to the use of larger diameter Al particles; however distinct increases in burning rates are found when CAB‐O‐SIL is removed and replaced with more energetic aluminum nanoparticles, whose high surface area allows them to also act as the gellant. Mixtures including fumed silica yield a reduced burning rate pressure exponent compared to neat NM, while mixtures of aluminum particles alone show a significant increase. Failure diameters of mixture detonations are found to vary significantly as a function of 38 nm aluminum particle loading, reducing more than 50% from that of neat nitromethane with 12.5% (by mass) aluminum loading. Failure diameter results indicate a relative minimum with respect to particle separation (% loading) which is not observed in other heterogeneous mixtures.  相似文献   
36.
OBJECTIVES: To assess the knowledge and clinical practice of dental students in infection control procedures at a UK dental hospital. DESIGN: A questionnaire concerning various aspects of infection control was completed by all clinical dental students under examination conditions. Their actual clinical practice was later observed and certain aspects recorded. SETTING: A UK dental hospital. SUBJECTS: One hundred and eleven dental students from three clinical years completed the questionnaire. Clinical practice for all 3 years was observed in a total of 280 treatment events. METHODS: The questionnaire was marked by two of the authors and observations recorded by another author. MAIN OUTCOME MEASURES: Degree of compliance with recognised policy for infection control. RESULTS: Knowledge of infection control procedures was variable particularly concerning duties usually undertaken by the dental nurse. The suggested high compliance with masks and eye protection was not always apparent in clinical practice, although virtually all students washed their hands prior to donning gloves, which were worn by all students. CONCLUSION: There can be marked differences between what students say they would do and what they actually do in clinical practice. The topic of infection control requires a pro-active approach throughout the course, since results for the final year were not significantly different from the other clinical years. Ways of improving compliance are discussed.  相似文献   
37.
This work presents a literature review of multiple classifier systems based on the dynamic selection of classifiers. First, it briefly reviews some basic concepts and definitions related to such a classification approach and then it presents the state of the art organized according to a proposed taxonomy. In addition, a two-step analysis is applied to the results of the main methods reported in the literature, considering different classification problems. The first step is based on statistical analyses of the significance of these results. The idea is to figure out the problems for which a significant contribution can be observed in terms of classification performance by using a dynamic selection approach. The second step, based on data complexity measures, is used to investigate whether or not a relation exists between the possible performance contribution and the complexity of the classification problem. From this comprehensive study, we observed that, for some classification problems, the performance contribution of the dynamic selection approach is statistically significant when compared to that of a single-based classifier. In addition, we found evidence of a relation between the observed performance contribution and the complexity of the classification problem. These observations allow us to suggest, from the classification problem complexity, that further work should be done to predict whether or not to use a dynamic selection approach.  相似文献   
38.
The main purpose of the current research was to develop an abbreviated form of the Dyadic Adjustment Scale (DAS) with nonparametric item response theory. The authors conducted 5 studies, with a total participation of 8,256 married or cohabiting individuals. Results showed that the item characteristic curves behaved in a monotonically increasing function for all items of the brief 4-item version of the DAS (DAS-4). The DAS-4 proved to be informative at all levels of couple satisfaction. Compared with the 32-item version of the DAS (DAS-32), it was as effective in predicting couple dissolution and was significantly less contaminated by socially desirable responding. In addition, structural equation modeling demonstrated that the underlying latent construct measured by the DAS-4 was very stable over a 2-year period. This brief version has the advantage of being less time consuming and constitutes a promising alternative to the original DAS-32 for clinicians and researchers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
40.
We have previously shown that monoclonal antibodies specific for a 280-kd protein (gp280) concentrated within the coated pits of renal and yolk sac brush border-induced fetal malformations, whereas antibodies specific for gp330, another coated pit protein with a similar distribution, had no deleterious effect on embryonic development. In this study, we show that gp280 and gp330 are closely related proteins, as indicated by: 1) similarities in peptide maps obtained after cyanogen bromide cleavage, 2) immunological cross-reactivity related to a minor contingent of antibodies that do not have teratogenic activity, and 3) asynchronous but related expressions during ontogenesis. During the early stages of development, the expression of the two glycoproteins was limited to (gp330) or predominant in (gp280) the clathrin-coated pits and intermicrovillar areas. In the pre-implantation embryo, gp330 was expressed by trophectodermal cells, which became negative in day-6 embryos trapped in endometrial infoldings. At this stage, gp280 and gp330 were both simultaneously detectable at the apical pole of the first entoblastic cells and remained expressed by the brush border of visceral yolk sac epithelial cells until the end of pregnancy. In addition, gp330 was expressed by amniotic cells and neurectodermal structures. During nephrogenesis, in contrast, the expression of gp280 and gp330 by the intermicrovillar areas of the proximal tubule cell was the result of a complex maturation process. gp280 and gp330 were diffusely distributed in S-shaped bodies in the presumptive areas of the glomerulus, proximal tubule, and distal tubule (gp330). During development of the nephron, the pattern of expression became progressively restricted to the proximal tubule and glomerulus (gp330), and selective localization in the intermicrovillar areas was only achieved in filtrating nephrons.  相似文献   
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