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1.
Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic...  相似文献   
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Uses principles of latent trait theory to derive conditions under which mean differences on an observed variable are indicative of mean differences on an underlying construct, focusing on the logistic curve as a model for describing the relation between the observed variable and construct. In this situation, and with normally distributed scores on the construct, a t test comparing groups on the observed variable produces correct inferences at the construct level only if group variances on the construct are homogeneous or the difficulty level of the test equals the mean ability level of the examinees. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We introduce a generalization of a deterministic relaxation algorithm for edge-preserving regularization in linear inverse problems. This algorithm transforms the original (possibly nonconvex) optimization problem into a sequence of quadratic optimization problems, and has been shown to converge under certain conditions when the original cost functional being minimized is strictly convex. We prove that our more general algorithm is globally convergent (i.e., converges to a local minimum from any initialization) under less restrictive conditions, even when the original cost functional is nonconvex. We apply this algorithm to tomographic reconstruction from limited-angle data by formulating the problem as one of regularized least-squares optimization. The results demonstrate that the constraint of piecewise smoothness, applied through the use of edge-preserving regularization, can provide excellent limited-angle tomographic reconstructions. Two edge-preserving regularizers-one convex, the other nonconvex-are used in numerous simulations to demonstrate the effectiveness of the algorithm under various limited-angle scenarios, and to explore how factors, such as the choice of error norm, angular sampling rate and amount of noise, affect the reconstruction quality and algorithm performance. These simulation results show that for this application, the nonconvex regularizer produces consistently superior results.  相似文献   
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In the last decades, the classification of schemes of haematological malignancies have undergone considerable changes both in terms of modifications of previous concepts and of methodological approaches, in parallel with the acquisition of new information on the physiopathological and functional pattern of haemic cells and of their precursors both at the lymph node and bone marrow level. The cyto-morphological aspects of haemic were better defined and integrated by the application of cyto- and histochemical methods, which were subsequently supplemented by bioenzymatic and cytogenetic techniques, then by immunophenotypical studies and finally by biomolecular investigations. Through the use of monoclonal antibodies and the introduction both in research and routine diagnostic practice of multiparameter analysis techniques, it is now possible to correlate several cellular parameters, to identify clonality of malignant cells as well as their lineage assignment and maturation stage. Flow cytometry has become an important, rapid and objective method for the diagnosis of haematological neoplasias. In the present survey we have illustrated the different expression of surface, cytoplasmic and nuclear antigens in haematological malignancies, their correlation with the clinical course of the disease and their diagnostic and prognostic significance.  相似文献   
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ABSTRACT

Our transdermal permeation studies of radioprotectors in permeation-enhancing vehicles led us to hypothesize that radiation-induced hair loss could be reduced by topical application of radioprotectors. In the present study we used a hair regrowth assay in “plucked” mice to measure the radioprotective effectiveness of WR-1065, cysteine and TEMPOL when they were dissolved in a variety of vehicles, i.e., saline, dimethyl formamide (DMF), propylene glycol (PG), dimethyl sulfoxide (DMSO), ethanol. Protector effectiveness varied with radiation dose and vehicles. At 600 R, WR-1065 or cysteine, in any vehicle, reduced radiation-induced baldness scores; at 800 R, only WR-1065 in DMF and cysteine in saline, produced some protection. TEMPOL in ethanol produced protection at both the 600 and 800 R. Results suggest that suitably chosen topical application of protector/vehicle combinations can reduce radiation-induced hair loss.  相似文献   
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This research studied homophily of network ties in distributed teams in both task-related instrumental networks and non-task related expressive networks. Homophily of network ties was examined in terms of demographic and social characteristics, including gender, race, geographic location, and group assignment. Social network data were collected from 32 students enrolled in a distance learning class from two universities. MQAP regression analysis showed that homophily in gender and in race had no significant impact on the development of either instrumental or expressive ties. In instrumental networks, both homophily in group assignment and in location had significant impact on the development of network ties. In expressive networks, homophily in location had significant impact on the development of network ties, but the impact of homophily in group membership was only marginally significant. Further analysis of bonding ties with people of the same group and bridging ties with people from different groups showed that bonding social capital can exert significant influence on performance.  相似文献   
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OBJECTIVES: The authors describe the relation of provider characteristics to processes, costs, and outcomes of medical care for elderly patients hospitalized for community-acquired pneumonia. METHODS: Using Medicare claims data, Medicare beneficiaries discharged from Pennsylvania hospitals during 1990 with community-acquired pneumonia were identified. Claims data were used to ascertain mortality, readmissions, use of procedures and physician consultations, and the costs of care. The relationship of these measures to provider characteristics was analyzed using regression techniques to adjust for patient characteristics, including comorbidity and microbial etiology. RESULTS: Among 22,294 pneumonia episodes studied, 30-day mortality was 17.0%. After adjusting for patient characteristics, 30-day mortality and readmission rates were unrelated to hospital teaching status or urban location or to physician specialty. Use of procedures and physician consultations was more common and costs were 11% higher among patients discharged from teaching hospitals compared with nonteaching hospitals. Similarly, costs were 15% higher at urban hospitals compared with rural hospitals. General internists and medical subspecialists used more procedures and had higher costs than family practitioners. CONCLUSIONS: Processes and costs of care for community-acquired pneumonia varied by provider characteristics, but neither mortality nor readmission rates did. These differences cannot be explained by clinical variables in the database. Further studies should determine whether less costly patterns of care for pneumonia, and perhaps other conditions, could replace more costly ones without compromising patient outcomes.  相似文献   
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Two extruded-expelled physically refined soybean oils with reduced contents of linolenic acid, ultra-low- linolenic acid (ULL, 1.5%) and low-linolenic acid (LL, 2.6%), and a extruded-expelled physically refined control oil (control, 5.3% linolenic acid) were evaluated by frying French fries in a commercial-like setting for 6 h day−1 during 23 days. The oils became darker, increased in yellow color at the beginning, and became redder and less green throughout the process. Free fatty acids levels were not different among the oils until day 14, after which, ULL was different from the control for the remainder of frying. The conjugated dienoic acid values were greatest in the control. Generally, ULL and LL oils had lower percentages of polar compounds than did the control, providing a frying life 2 days longer than the control and ~30% increase in frying time. A trained sensory panel evaluated the French fries on days 2, 5, and 6. Buttery and potato flavors decreased, and rancid and painty flavors increased over frying time for all products. Rancid flavor was highest in the fries from the control oil. Overall, the ULL and LL oils performed better than did the control oil and ULL tended to perform better than the LL.  相似文献   
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