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91.
A carrier fringe techrtique for measuring surface deformation is described and verified by experiments. In contrast to conventional holography and fringe analysis, this holographic system is based on fibre optics and automatic spatial carrier fringe pattem analysis techniques Single-mode optic fibres are used to transfer both the object and reference beams. Carrier fringes are generated by simply translating the object beam between two exposures The Fourier transform is applied to the carrier fringe pattern to convert it to the spatial frequency domain, where it is processed The results are given for a centrally loaded disk, including a 3-D perspective plot of the out of plane deformation field, phase map, grey level map and contour map. 相似文献
92.
The authors report results from 2 studies assessing the extent to which narcissism is related to self- and other ratings of leadership, workplace deviance, and task and contextual performance. Study 1 results revealed that narcissism was related to enhanced self-ratings of leadership, even when controlling for the Big Five traits. Study 2 results also revealed that narcissism was related to enhanced leadership self-perceptions; indeed, whereas narcissism was significantly positively correlated with self-ratings of leadership, it was significantly negatively related to other ratings of leadership. Study 2 also revealed that narcissism was related to more favorable self-ratings of workplace deviance and contextual performance compared to other (supervisor) ratings. Finally, as hypothesized, narcissism was more strongly negatively related to contextual performance than to task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
An increasing number of multiport devices, whether they be multiband wireless phone components, backplane balanced transmission lines, or classical devices such as power dividers, are being characterized in the RF, microwave, and millimeter-wave frequency bands. S-parameter measurements are often required, and ordinary vector network analyzer (VNA) measurements must be modified to perform these measurements quickly and accurately. This article explores a number of hardware architectures and calibration procedures for multiport measurements and their impacts on flexibility and uncertainties. 相似文献
94.
A photoionization system has been developed for flow injection and liquid chromatographic applications that employs photovoltaic rather than traditional photoconductive detection. This detection system utilizes an excimer laser at 248 nm (5.0 eV) to achieve one-photon excitation in alcoholic, aqueous, and ionic solutions. The photovoltaic response is reported for a variety of solutes including aliphatic and aromatic amines, aldehydes, ketones, carboxylic acids, and halogenated compounds. The photovoltaic method is characterized with respect to solute concentration and flow rate. The detection limit is 5 × 10(-)(6) M (2.3 ng) for aniline in methanol with a linear dynamic range greater than 2 orders of magnitude, which compares favorably to UV-visible absorbance detection. Photovoltaic detection is demonstrated for a series of substituted anilines and aldehydes separated by reversed-phase liquid chromatography. 相似文献
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LV Solov'eva MP Svetlova R Hancock R Whittle AR Lehmann D Bootsma NV Tomilin 《Canadian Metallurgical Quarterly》1996,38(12):1294-1302
An auxiliary protein of DNA polymerases delta and epsilon, the proliferating cell nuclear antigen (PCNA), is necessary for efficient DNA replication in vivo and in vitro, and also for the repair synthesis in vitro, but its role in the excision repair of genome in vivo is not exactly established. In S-phase of unirradiated cells, PCNA is tightly bound to focal centers of DNA replication and is not removed by treatment with detergent Triton X-100, but is completely extracted from non-S-phase cells by the indicated detergent. It was shown earlier that after UV-irradiation PCNA could not be removed by the detergent even from non-S-phase cells. It was interpreted as the evidence of PCNA integration into the repair complex and of the participation of this protein in repair synthesis in vivo. In the present work the data were obtained indicating that the role of PCNA in cell response to UV-damage was not confined only to its possible involvement in repair synthesis. With the help of confocal microscopy it was established that in Triton X-100-extracted normal cells PCNA did not colocalize with the well known excision repair protein XPB/ERCC3, defective in cells from Xeroderma pigmentosum (complementation group B) patients. XPB-protein is induced by UV-irradiation in normal cells, and this induction is not observed in repair deficient cells. However, in such cells UV-light induces a detergent-resistant form of PCNA, and this form is obviously not connected with repair. It cannot be excluded that a rapid PCNA immobilization immediately after UV-irradiation of cells is needed for the facilitation of photochemical damage bypass during the subsequent replication of genome. 相似文献
97.
Twenty-eight site-directed mutations were introduced into the fission yeast gene (pcn1+) that encodes proliferating cell nuclear antigen (PCNA) and their in vivo effects analyzed in a strain with a null pcn1 background. Mutants defective in enhancing processivity of DNA polymerase delta have previously been identified. In this study, we assessed all of the mutants for their sensitivities to temperature, hydroxyurea, UV irradiation and methyl methanesulfonate (MMS), and specific mutants were also tested for sensitivity to gamma irradiation. One cold-sensitive allele, pcn1-3, was characterized in detail. This mutant had a recessive cold-sensitive cdc phenotype and showed sensitivity to hydroxyurea, UV, and gamma irradiation. At the non-permissive temperature pcn1-3 protein was able to form homotrimers in solution and showed increased stimulation of both synthetic activity and processivity of DNA polymerase delta relative to the wild-type Pcn1+ protein. Epistasis analyses indicated that pcn1-3 is defective in the repair pathway involving rad2+ but not defective in the classical nucleotide excision repair pathway involving rad13+. Furthermore, pcn1-3 is either synthetically or conditionally lethal in null checkpoint rad backgrounds and displays a mitotic catastrophe phenotype in these backgrounds. A model for how pcn1-3 defects may affect DNA repair and replication is presented. 相似文献
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