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71.
Polyglandular autoimmune syndrome (PGAS) type 2 (Schmidt syndrome) is characterized by the association of primary adrenocortical insufficiency with autoimmune thyroid disease, and/or insulin-dependent diabetes mellitus (IDDM). In this report we describe the occurrence of two episodes of post-partum thyroiditis (PPT) after a first and second pregnancy as well the development acutely of adrenal insufficiency after a second pregnancy. A family history of autoimmune thyroid disease and IDDM as well as positive antiadrenal and antithyroid antibodies and HLA typing is evidence for an underlying polyendocrine autoimmune syndrome. This case report provides further evidence that the immune system that is suppressed in pregnancy to tolerate the fetal allograft can rebound post-partum to unmask polyendocrine autoimmune disorders such as adrenalitis and PPT in susceptible women.  相似文献   
72.
We examined the influences of different facets of psychological collectivism (Preference, Reliance, Concern, Norm Acceptance, and Goal Priority) on team functioning at 3 different performance depictions: initial team performance, end-state team performance, and team performance change over time. We also tested the extent to which team-member exchange moderated the relationships between facets of psychological collectivism and performance change over time. Results from multilevel growth modeling of 66 teams (N = 264) engaged in a business simulation revealed differential effects across facets of psychological collectivism and across different performance measurements. Whereas facets concerned with affiliation (Preference and Concern) were positively related to initial team performance, reliance was negatively related to initial team performance. Goal Priority was a strong predictor of end-state performance. Team-member exchange moderated the relationship between performance change and 3 of the 5 facets of psychological collectivism (Preference, Reliance, Norm Acceptance). Implications for team composition and team training are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
73.
A new pseudoreceptor modeling method (PRPS) was applied to the refinement of a homology model of the human histamine H4 receptor (H4R), the prediction of a ligand binding site, and virtual screening. Retrieval of two new H4R ligands demonstrates the biological relevance of the pseudoreceptor model and provides a means for finding new hits and leads in the early phases of drug discovery.

  相似文献   

74.
Polyethylene (PE) nanocomposites with the zinc oxide-nanoparticles/vermiculite nanofiller were prepared in two-steps. In first step, the ZnO-np/V nanofiller were prepared by the mechanochemical method followed by a heat treatment at 650?°C for 90 min. In second step, this nanofiller was used in concentration 3, 6, 10 and 15 wt% for PE nanocomposites preparation via melt compounding technique, the nanocomposites plates were pressed. The particles morphology of the ZnO-np/V nanofiller, arrangement of the ZnO-np/V nanofiller and surface of the PE plates were studied using scanning electron microscopy, optical light microscopy and atomic force microscopy. The surface roughness of the PE plates was evaluated from AFM measurements. Structural changes of the ZnO-np/V nanofiller in PE nanocomposites were monitored using X-ray diffraction analysis and Fourier transform infrared analysis. The gradual and long-term antibacterial effect of PE nanocomposites was tested on the Gram positive bacteria E. faecalis by counting the colony forming units number.  相似文献   
75.
Coatings are used in a variety of applications. Last decades more and more coating systems are transforming from solvent to waterborne coating systems. In this study the influence of pigments on the water permeability of a waterborne coating system is studied, with special interest in the possible interfacial layer of additives around the pigments. In our study an acrylate based binder is mixed with different glass sphere concentrations and sizes. Subsequently, the coating permeability is studied through wet-cup experiments and water uptake in the coating, either on a glass substrate or on wood, is monitored with NMR. These experiments show that water is absorbed more quickly by coatings containing glass spheres. From the experimental results it can be concluded that an interface layer around the pigment particles facilitates water migration and increases the effective diffusion. A modification of the effective medium theory is used to describe the observation and good agreement between experiments and theory is obtained. Both theory and experiment show that in a coating a layer around the pigments facilitates water transport and increases the effective diffusion constant.  相似文献   
76.
This study examined perceptions of school psychologists regarding their use of evidence-based interventions in school settings after completing a graduate course in school-based psychosocial interventions. Ninety-four individuals who completed the course during the 10 years prior to the study were asked to complete a survey that focused on personal and organizational factors affecting the implementation of evidence-based interventions through assessment of (a) the extent of their use of interventions in professional school psychology practice, (b) perceptions of facilitators to implementation, and (c) perceptions of barriers to implementation. Fifty-four responded (a 57% response rate); analyses were conducted on the responses of 34 individuals who indicated that they were currently school psychologists working in schools. Results indicated that school psychologists’ personal beliefs about the interventions influenced their decisions to implement them. Several evidence-based interventions were less likely to be used in urban practice settings. Training in evidence-based interventions should address the personal and contextual issues that are related to implementation, as well as the procedures of the interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
We review recent friction measurements on ordered superstructures performed by atomic force microscopy. In particular, we consider ultrathin KBr films on NaCl(001) and Cu(001) surfaces, single and bilayer graphene on SiC(0001), and the herringbone reconstruction of Au(111). Atomically resolved friction images of these systems show periodic features spanning across several unit cells. Although the physical mechanisms responsible for the formation of these superstructures are quite different, the experimental results can be interpreted within the same phenomenological framework. A comparison between experiments and modeling shows that, in the cases of KBr films on NaCl(001) and of graphene films, the tip-surface interaction is well described by a potential with the periodicity of the substrate which is modulated or, respectively, superimposed with a potential with the symmetry of the superstructure.  相似文献   
78.
This paper presents novel algorithms which are able to generate recommendations within a heterogeneous service environment. In this work explicitly set preferences as well as implicitly logged viewing behavior are employed to generate recommendations for Digital Video Broadcast (DVB) content. This paper also discusses the similarity between the DVB genres and YouTube categories. In addition it presents results to show the comparison between well known collaborative filtering methods. The outcome of this comparison study is used to identify the most suitable filtering method to use in the proposed environment. Finally the paper presents a novel Personal Program Guide (PPG), which is used as a tool to visualize the generated recommendations within a heterogeneous service environment. This PPG is also capable of showing the linear DVB content and the non-linear YouTube videos in a single view.  相似文献   
79.
Carbon nanotube papers (CNT papers, also referred to as “buckypapers”) prepared from chemically functionalized single-walled CNTs are being investigated for their mechanical tensile properties. While the Young’s moduli are unaffected by the functionalization with diazonium salts of aniline or aromatic mono- and bis-amides tensile strengths of CNT papers are found to increase with a growing degree of functionalization, and more pronounced with a growing number of amide groups capable of hydrogen bonding. The importance of hydrogen bonding becomes evident after its inhibition through N-methylation of the amide groups, resulting in a distinct reduction of strength values. Scanning electron micrography indicates that a high degree of functionalization or a high number of amide group results in the formation of domains with aligned CNTs.  相似文献   
80.
A failure mechanism of submarine landslides based on the phenomenon of shear band propagation has been investigated using the energy balance approach. Dynamic analysis includes inertia effects in the sliding layer and viscous resistance of the water, but ignores elastic and plastic wave propagation in the sliding layer. The resulting differential equation has been solved numerically. Analytical approximation of this numerical solution provides a convenient basis for the parametric and sensitivity studies. The solution allows assessing the velocity and acceleration of both the landslide and the shear band at the moment when the slide fails due to the limiting equilibrium (i.e., the initial post-failure velocity). The effects of the initial landslide velocity on the tsunami wave height are discussed and validated for a number of landslide examples.  相似文献   
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