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991.
992.
The water uptake of nominally 5%-Yb-doped strontium zirconate (SrZr0.95 Yb0.05 O3−α ) was studied in situ by thermogravimetry at different temperatures and water vapor pressures. The process could be described in terms of an ideal solution behavior, showing a lower effective vacancy concentration than that expected from the nominal dopant content. The solution reaction was found to have ΔS°=−127 J/(mol·K) and ΔH°=−106 kJ/mol. 相似文献
993.
Schmidt Frank L.; Hunter John E.; Outerbridge Alice N. 《Canadian Metallurgical Quarterly》1986,71(3):432
Based on data from 4 independent studies reported by R. Vineberg and E. N. Taylor (1972) with a total sample size of 1,474, path analysis was used to examine the causal impact of job experience on job knowledge, performance capability as measured by job sample tests, and supervisory ratings of job performance. Findings support the conclusion that (1) when mean job experience is 2–3 yrs, there is substantial variance in job experience and (2) when the jobs are of an intermediate complexity level, job experience has a substantial direct impact on job knowledge and a smaller direct impact on performance capabilities as assessed by job sample measures. Job experience also has a substantial indirect effect on work sample performance through its effect on job knowledge, which, in turn, was found to be the strongest determinant of work sample performance. The pattern and magnitude of causal effects of general mental ability were similar to those of job experience. The effect of job knowledge on supervisory ratings was several times stronger than the effect of job sample performance, confirming the findings of J. E. Hunter (1983). When job experience was held constant, the direct impact of ability on the acquisition of job knowledge increased substantially, and this, in turn, increased the indirect effect of ability on job sample performance. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
995.
A THEORETICAL SOLUTION FOR THE ESTIMATION OF "RAINFLOW" RANGES FROM POWER SPECTRAL DENSITY DATA 总被引:2,自引:0,他引:2
N. W. M. Bishop Frank Sherratt 《Fatigue & Fracture of Engineering Materials & Structures》1990,13(4):311-326
Abstract— This report outlines a theoretical solution for the estimation of rainflow range density functions using statistics computed directly from power spectral density data. The rainflow range mechanism is broken down into a set of events which can be analyzed using Markov process theory. The dependence between extremes in this instance is modelled using an approximation of the joint distribution of peaks and troughs first proposed by Kowalewski. 相似文献
996.
Beach Steven R. H.; Fincham Frank D.; Amir Nader; Leonard Kenneth E. 《Canadian Metallurgical Quarterly》2005,19(2):276
This study used taxometric methods to investigate the latent structure of the construct of marital adjustment as indexed by the Marital Adjustment Test (MAT; H. J. Locke & K. M. Wallace, 1959). That is, the authors examined whether marital adjustment is best thought of as a "dimension" of adjustment only or whether there also are categorical differences between "discordant" and "nondiscordant" couples. Analyses of data provided by 447 couples married for approximately 2 years provided converging evidence for a latent category of marital discord, suggesting that marital discord can be viewed as a qualitatively distinct state experienced by approximately 20% of the couples in the current sample. Implications for marital assessment are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
McCullough Michael E.; Fincham Frank D.; Tsang Jo-Ann 《Canadian Metallurgical Quarterly》2003,84(3):540
The investigators proposed that transgression-related interpersonal motivations result from 3 psychological parameters: forbearance (abstinence from avoidance and revenge motivations, and maintenance of benevolence), trend forgiveness (reductions in avoidance and revenge, and increases in benevolence), and temporary forgiveness (transient reductions in avoidance and revenge, and transient increases in benevolence). In 2 studies, the investigators examined this 3-parameter model. Initial ratings of transgression severity and empathy were directly related to forbearance but not trend forgiveness. Initial responsibility attributions were inversely related to forbearance but directly related to trend forgiveness. When people experienced high empathy and low responsibility attributions, they also tended to experience temporary forgiveness. The distinctiveness of each of these 3 parameters underscores the importance of studying forgiveness temporally. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
C Maercker S Stoll K Rosenkranz EM Becker HJ Lipps 《Canadian Metallurgical Quarterly》1997,21(3):201-211
A repetitive element from the hypotrichous ciliate Stylonychia lemnae was characterized by restriction and hybridization analysis. This repetitive element is present in about 5,000-7,000 copies per haploid genome in the micronucleus and the macronuclear anlagen. Its DNA sequence is very conserved, but the length of the repetitive sequence blocs is variable. In some cases, it is associated with telomeric sequences and macronucleus-homologous sequences. Restriction analysis of genomic micronuclear and macronuclear anlagen DNA and in situ hybridization showed that the repetitive sequences are amplified during the formation of polytene chromosomes. They are localized in many bands of the polytene chromosomes and are eliminated during the degradation of the polytene chromosomes. Possible functions of the repetitive sequences during macronuclear differentiation are discussed. 相似文献
999.
J Rugtveit EM Nilsen A Bakka H Carlsen P Brandtzaeg H Scott 《Canadian Metallurgical Quarterly》1997,112(5):1493-1505
BACKGROUND & AIMS: Most macrophages in the normal intestinal mucosa have a mature phenotype. In inflammatory bowel disease (IBD), a monocyte-like subset (CD14+ L1+) accumulates. The aim of this study was to characterize its potential with regard to cytokines. METHODS: Lamina propria mononuclear cells were adherence-separated, with or without depletion of CD14+ cells, and production of cytokines was investigated by bioassay, enzyme-linked immunosorbent assay, or immunocytochemistry. RESULTS: Tumor necrosis factor alpha (TNF-alpha), interleukin 1beta (IL-1beta), and IL-1 receptor antagonist were found mainly in cells positive for myelomonocytic L1. In undepleted IBD cultures, TNF-alpha, IL-1alpha and beta, and IL-10 were markedly up-regulated by pokeweed mitogen stimulation; IL-1alpha and beta and IL-10 were also up-regulated by stimulation of interferon gamma and lipopolysaccharide in combination. The latter stimulation had no effect on normal control or CD14-depleted IBD cultures. Indomethacin caused a marked increase of TNF-alpha, particularly in undepleted IBD cultures, whereas IL-10 and IL-4 decreased TNF-alpha and IL-1beta in both CD14+ and CD14 macrophages. CONCLUSIONS: In IBD mucosa, macrophages with a monocyte-like phenotype are primed for production of TNF-alpha and IL-1alpha/beta and may therefore be of significant pathogenic importance [corrected]. However, this CD14+ subset, as well as the mucosal resident macrophages, have preserved responsiveness to several down-regulatory factors such as the macrophage deactivators IL-10 and IL-4. 相似文献
1000.
The convective transport of fluid and of a binding antibody through a cultured tumor cell layer was investigated with a mouse melanoma cell line (B16F10) grown on a microporous polycarbonate filter (Snapwell inserts). The inserts were precoated with Matrigel or collagen, or were uncoated. The cell layers were exposed to nominal pressure gradients from 5 to 25 cm H2O, and the volume flux was measured by collecting the effluent volume over time. The rate of convective transport of a binding monoclonal antibody that recognizes the murina transferrin receptor (a-TfR) was investigated at a nominal pressure gradient of 15 cm H2O and compared with that of an isotype matched, nonbinding control. The resistance, R, of the cell layer to fluid flow was quantified as the hydraulic conductivity, Lp (= 1/R); the ability of the cell layer to retard antibody transport was quantified as the reflection coefficient, sigma. The resulting Lp values decreased with increasing cell density, in a manner consistent with Poiseuille flow. Collagen or Matrigel precoating also decreased Lp values, with cells grown on Matrigel providing the greatest resistance. The sigma values were 0.67 (+/-0.08) for the a-TfR antibody and 0.51 (+/-0.06) for the control, indicating that the cell layer acts as a semipermeable barrier to convective transport of antibody that is less permeable to the binding antibody. 相似文献