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排序方式: 共有895条查询结果,搜索用时 15 毫秒
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In this paper, the authors present the results of experiments which clearly demonstrate a technical basis confirming that the carrier frequency harmonics data can be used for diagnostics relative to motor stator insulation degradation. 相似文献
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Izard Carroll E.; Fantauzzo Christina A.; Castle Janine M.; Haynes O. Maurice; Rayias Maria F.; Putnam Priscilla H. 《Canadian Metallurgical Quarterly》1995,31(6):997
Four studies examined aspects of the differential emotions theory (DET) hypothesis of expressive behavior development. In Study 1, facial-expressive movements of 108 2.5–9-mo-old infants were video recorded in positive and negative mother–infant interactions (conditions). As expected, Max-specified full-face and partial expressions of interest, joy, sadness, and anger were morphologically stable between the 2 ages. Studies 1 and 2 confirmed predicted differential responding to mother sadness and anger expressions and to composite positive and negative conditions. Discrete negative expressions exceeded negative blends, and the amount of both expression types remained stable across ages. Studies 3 and 4 provided varying degrees of support for the social validity of Max-specified infant negative affect expressions. Conclusions include revisions and clarifications of DET. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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According to hopelessness theory, hopelessness expectancy is the proximal, sufficient cause of hopelessness depression. Consequently, hopelessness expectancy is viewed as mediating the influence of all other factors on hopelessness depression. Using a longitudinal research design, hopelessness expectancy was examined as a mediator of the relation between illness attributions and hopelessness depression in a sample of 57 adults with rheumatoid arthritis. Although hopelessness expectancy was a strong predictor of hopelessness depression, it moderated rather than mediated the relation between attributions and depression. Finding support for a moderating rather than a mediating model is inconsistent with theory but is consistent with the findings of J. H. Riskind et al (1987). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Haynes Stephen N.; Lemsky Carolyn; Sexton-Radek Kathy 《Canadian Metallurgical Quarterly》1987,18(5):515
Findings from several studies have indicated that the scientist-practitioner model (which stresses the integration of research into clinical practice) is infrequently adopted by practicing clinical psychologists. Although many hypotheses have been offered, there have been no empirical examinations of the reasons why clinicians infrequently engage in research. In this study, 79 practicing clinical psychologists completed a questionnaire focusing on perceived impediments to clinical research. A number of inhibiting factors were identified, but the intrinsic and extrinsic contingencies associated with the conduct of research were most salient. Other concerns included ethics, the impact of research on the clinical process, and the unavailability of appropriate research designs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Chromium is a redox active 3d transition metal with a wide range of valences (−2 to +6) that control the geochemistry and toxicity of the element. Therefore, techniques that measure Cr valence are important bio/geochemical tools. Until now, all established methods to determine Cr valence were bulk techniques with many specific to a single, or at best, only a few oxidation state(s). We report an electron energy loss spectroscopy (EELS) technique along with an extensive suite of affined reference spectra that together, unlike other methods, can determine Cr valence (or at least constrain the possible valences) at high-spatial resolution (tens-of-nanometer scale) across a wide valence range, Cr(0)–Cr(VI). Fine structure of Cr-L2,3 edges was parametrized by measurement of the chemical shift of the L3 edge and the ratio of integrated intensity under the L3 and L2 edges. These two parameterizations were correlated to Cr valence and also the dn orbital configuration which has a large influence on L-edge fine structure. We demonstrate that it is not possible to unambiguously determine Cr valence from only one fine-structure parameterization which is the method employed to determine metal valence by nearly all previous EELS studies. Rather, multiple fine-structure parameterizations must be used together if the full range of possible Cr valences is considered. However even with two parameterizations, there are limitations. For example, distinguishing Cr(IV) from Cr(III) is problematic and it may be difficult to distinguish low-spin Cr(II) from Cr(III). Nevertheless, when Cr is known to be divalent, low- and high-spin dn orbital configurations can be readily distinguished. 相似文献
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Christensen Anne-Lise; Malmros Richard; Townes Brenda D. 《Canadian Metallurgical Quarterly》1987,1(2):45
After suffering a rupture of a left-sided aneurysm on the middle cerebral artery with prolonged arterial spasms, the prognosis for recovery of speech and motor functions of a 27-yr-old male patient was considered to be poor. Based on a Luria neuropsychological investigation that revealed many areas of preserved brain functions, rehabilitation efforts were directed toward training of specific abilities as well as compensatory skills using intact functions. This case demonstrates the interaction between the training program and the levels of motivation and persistence of the S and his family necessary to produce optimal rehabilitation outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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RE Sacco JS Haynes JA Harp WR Waters MJ Wannemuehler 《Canadian Metallurgical Quarterly》1998,153(6):1717-1722
Flora-bearing mice with targeted disruption of T cell receptor (TCR)-alpha or -beta genes spontaneously develop intestinal inflammation with features similar to ulcerative colitis in humans. TCR-alpha-deficient mice maintained germfree or colonized with a limited number of intestinal bacteria failed to develop inflammatory bowel disease (IBD)-like lesions. Evidently, inflammation in these mice does not develop spontaneously or result from a generalized antigenic stimulation, but rather requires induction by a heretofore unidentified specific stimulus. We describe the development of IBD-like lesions in germfree TCR-alpha-deficient mice monoassociated with the protozoan Cryptosporidium parvum. Lesions were seen in distal ileum, cecum, and colon and were most severe in the cecum. A prominent leukocytic infiltrate within the lamina propria was a common characteristic of the lesions observed in the C. parvum-infected germfree TCR-alpha-deficient mice. The leukocytic infiltrate was composed of aggregates of B220+ cells, the majority of which expressed surface IgD (ie, conventional B lymphocytes). It has been proposed that antigenic stimulation by a microorganism(s) is needed to initiate intestinal inflammation in TCR-alpha-deficient mice. Our results indicate that a single microbial species, C. parvum, is capable of triggering the development of IBD-like lesions in germfree TCR-alpha-deficient mice. 相似文献
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Driscoll MM Haynes JT Jelen RA Weinert RW Gavaler JR Talvacchio J Wagner GR Zaki KA Liang XP 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1992,39(3):405-411
Ultra-high Q, X-band resonators, used in a frequency discriminator for stabilization of a low-noise signal generator, can provide a means of obtaining significant reduction in phase noise levels. Resonator unloaded Qs on the order of 500 K can be obtained in sapphire dielectric resonator (DR) operating on a low-order (i.e. TE(01)) mode at 77 K and employing high-temperature superconducting (HTS) films installed in the DR enclosure covers. Rigorous analysis for the determination of resonator frequency, modes, and unloaded Q have been carried out using mode matching techniques. Trade-off studies have been performed to select resonator dimensions for the optimum mode yielding highest unloaded Q and widest spurious mode separation. Field distributions within the resonator have been computed to enable practical excitation of the required mode. The results of both analysis and prototype device evaluation experiments are compared for resonators fabricated using enclosures consisting of conventional, metal sidewalls and covers employing HTS films as a function of cover conductivity. 相似文献