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1.
H. H. Kendler (see record 1994-09190-001), in his article on psychology and the ethics of social policy, argues in part that ethical imperatives cannot be inferred from empirical data. This argument is cited in opposition to what is purported to be the position of the American Psychological Association on the abortion issue. It is suggested that PhD candidates in psychology be well versed in the philosophical issues and debates that are the foundation for the formation of ethical principles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Substituting Y in orthorhombic (Y,RE)Ba2Cu3O7 by any rare-earth element RE has generally little effect on the superconducting properties. For RE = Pr, however, superconductivity is completely suppressed. To elucidate this effect we have studied the unoccupied electronic structure of PrxY1–xBa2Cu3O7–y (x = 0.0,0.4, 0.8) by polarization-dependent O1s x-ray absorption spectroscopy on detwinned single crystals. Along with the comparison of undoped (y 0.9) to the doped materials (y 0.1), this allows a test of the current theoretical explanations for the suppression of superconductivity. While we can rule out models involving hole filling or charge transfer from planes to chains our data is consistent with approaches based on Pr4f–02p hybridization.  相似文献   
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This study investigated the efficacy of a method of parent training and parent reading tutoring that built on past research. Parents of five first-grade children who were reading below grade level participated. Parents were trained to implement a tutoring procedure that included modeling, practice, phonics, fluency building, accuracy building, comprehension, and reinforcement components. Assessment of audiotape recordings and permanent products indicated high levels of treatment integrity. A multiple baseline across participants design was used to assess the results. Four of the five children exhibited an increase in words read correctly per minute on tutored reading passages. Issues that arose in the implementation of this study are discussed, as well as research regarding how to tailor home tutoring procedures to parent-child dyads. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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TachoComb is a new, ready-to-use hemostatic agent consisting of a collagen sheet coated on one side with human fibrinogen, bovine thrombin, and bovine aprotinin. The product was used in 125 surgical operations (vascular, hepatic, urological and ENT) in which secondary hemostasis was required. It was placed over the cut surface or over the edges of the wound. The investigating surgeons expressed their opinion on the intra- and postoperative hemostatic efficacy, and routine laboratory tests were done postoperatively. TachoComb had good hemostatic efficacy in 67.2% of cases, and very good in 22.4%. No noteworthy systemic changes were observed. As an adjuvant to obtain complete hemostasis in surgery, TachoComb is effective, practical and quick to use, and is very well tolerated.  相似文献   
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Polymer nanocomposites are increasingly used in applications that are subjected to harsh environments. Owing to polymer's susceptibility to photodegradation, nanofillers in a polymer nanocomposite may be released into the environments during the composite's life cycle. Such release potentially poses an environmental health and safety problem and may hinder commercialization of these advanced materials. This study investigated the fate and release of nanosilica from epoxy/nanosilica composites. Specially-designed holders containing nanocomposite specimens were irradiated with UV light in a well-controlled environmental chamber. UV irradiated samples were removed for measurements of polymer chemical degradation, mass loss, surface morphology, nanosilica accumulation on the composite surface, and nanosilica release. Epoxy matrix underwent rapid photodegradation, resulting in substantial accumulation of silica nanofillers on the composite surface and also release from the composite. A conceptual model for surface accumulation and release of nanosilica during UV irradiation of epoxy nanocomposites is presented.  相似文献   
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A new strategy is proposed to stabilize the electro-optic (EO) activity of second-order materials using copper-free thermal Huisgen 1,3-dipolar cross-linking reaction. It consists in freezing the chromophores orientation after the poling process by a cross-linking reaction based on the 1,3-dipolar cycloaddition between an azide and an alkyne. To reach this goal, the synthesis of new methacrylate type polymers bearing a derivative of Disperse Red 1 chromophore was performed. The polymeric structure is bearing a cross-linkable function on its backbone and the complementary reactive function is brought by a small molecule called “doping agent” (DA), containing several complementary cross-linking groups, evenly distributed in the polymer film. Materials have been prepared and exhibit large second-order nonlinear optical coefficients (d33) up to 60 pm/V at the fundamental wavelength of 1064 nm. Moreover, the thermal stability of the orientation of the chromophores could reach 150 °C upon cross-linking with such materials, which is higher than previously described cross-linkable EO polymers based on this reaction. Furthermore, this new strategy widens the possibilities offered by copper-free thermal Huisgen 1,3-dipolar cycloaddition as cross-linking reaction for EO polymers.  相似文献   
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Four strains of filamentous bacteria were isolated from slimes collected in different paper mill factories. Morphological and physiological characterization of the isolates indicated an affiliation with the genus Sphaerotilus. However, while the physiological properties of the isolates were almost identical, pronounced physiological differences between the isolates and Sphaerotilus natans DSM 6575(T), DSM 565, and DSM 566 with respect to their ability to metabolize complex polysaccharides, sugars, polyalcohols, or organic acids as carbon sources were detected. In contrast to the analyzed culture collection strains of S. natans, all paper mill isolates were able to grow at elevated temperatures of up to 40 degrees C. Comparative sequence analysis of nearly complete 16S ribosomal DNA (rDNA) sequences from the four new isolates demonstrated that the retrieved sequences were highly similar to each other (99.6 to 99.8% similarity) and to previously published partial 16S rDNA sequences of S. natans DSM 6575(T) and ATCC 15291. Polyphasic characterization of the isolated Sphaerotilus strains revealed interesting adaptations of the strains to the environmental paper mill conditions with regard to temperature tolerance and utilization of cellulose and starch.  相似文献   
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