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91.
HM Cox 《Canadian Metallurgical Quarterly》1997,3(4):218-223
This paper describes one aspect of a study into the experiences in long-term healing of a community following the 1983 Ash Wednesday bushfire. Forty participants were interviewed, of whom 26 were residents and 14 disaster relief workers. The paper concentrates on the experiences of the latter, describing how they came to understand the bushfire affected the community and how they managed disaster work. For novices it was a profoundly difficult experience, for which they received little help and had to manage with whatever skill they drew on in their 'normal' working lives, mixed with a good deal of intuition. The paper suggests that health workers in vulnerable areas require preparation for a likely disaster; that 'outsiders' need to deal through existing community groups and individuals to gain access to those in need of their skills, and that they also require preparation for helping 'insiders' who are themselves victims of the catastrophe. 相似文献
92.
Goff Phillip Atiba; Eberhardt Jennifer L.; Williams Melissa J.; Jackson Matthew Christian 《Canadian Metallurgical Quarterly》2008,94(2):292
Historical representations explicitly depicting Blacks as apelike have largely disappeared in the United States, yet a mental association between Blacks and apes remains. Here, the authors demonstrate that U.S. citizens implicitly associate Blacks and apes. In a series of laboratory studies, the authors reveal how this association influences study participants' basic cognitive processes and significantly alters their judgments in criminal justice contexts. Specifically, this Black-ape association alters visual perception and attention, and it increases endorsement of violence against Black suspects. In an archival study of actual criminal cases, the authors show that news articles written about Blacks who are convicted of capital crimes are more likely to contain ape-relevant language than news articles written about White convicts. Moreover, those who are implicitly portrayed as more apelike in these articles are more likely to be executed by the state than those who are not. The authors argue that examining the subtle persistence of specific historical representations such as these may not only enhance contemporary research on dehumanization, stereotyping, and implicit processes but also highlight common forms of discrimination that previously have gone unrecognized. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
HM Sansbury AE Wisehart-Johnson C Qi S Fulwood KE Meier 《Canadian Metallurgical Quarterly》1997,18(9):1817-1824
Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12-myristate 13-acetate with activation of ERK mitogen-activated protein kinases, synthesis of interleukin-2, and death, whereas phorbol ester-resistant variants of this cell line do not exhibit these responses. Additional aspects of the resistant phenotype were examined, using a newly-established resistant cell line. Phorbol ester induced morphological changes, ERK activation, calcium-dependent activation of the c-Jun N-terminal kinase (JNK), interleukin-2 synthesis, and growth inhibition in sensitive but not resistant cells. A series of protein kinase C activators caused membrane translocation of protein kinase C's (PKCs) alpha, eta, and theta in both cell lines. While PKC eta was expressed at higher levels in sensitive than in resistant cells, overexpression of PKC eta did not restore phorbol ester-induced ERK activation to resistant cells. In sensitive cells, PKC activators had similar effects on cell viability and ERK activation, but differed in their abilities to induce JNK activation and interleukin-2 synthesis. PD 098059, an inhibitor of the mitogen activated protein (MAP)/ERK kinase kinase MEK, partially inhibited ERK activation and completely blocked phorbol ester-induced cell death in sensitive cells. Thus MEK and/or ERK activation, but not JNK activation or interleukin-2 synthesis, appears to be required for phorbol ester-induced toxicity. Alterations in phorbol ester response pathways, rather than altered expression of PKC isoforms, appear to confer phorbol ester resistance to EL4 cells. 相似文献
94.
Stphane Y. Le Goff 《International Journal of Communication Systems》2002,15(7):621-633
Introduced in 1993, turbo codes can achieve high coding gains close to the Shannon limit. In order to design power and bandwidth‐efficient coding schemes, several approaches have been introduced to combine high coding rate turbo codes with multilevel modulations. The coding systems thus obtained have been shown to display near‐capacity performance over additive white Gaussian noise (AWGN) channels. For communications over fading channels requiring large coding gain and high bandwidth efficiency, it is also interesting to study bit error rate (BER) performance of turbo codes combined with high order rectangular QAM modulations. To this end, we investigate, in this paper, error performance of several bandwidth‐efficient schemes designed using the bit‐interleaved coded modulation approach that has proven potentially very attractive when powerful codes, such as turbo codes, are employed. The structure of these coding schemes, termed ‘bit‐interleaved turbo‐coded modulations’ (BITCMs), is presented in a detailed manner and their BER performance is investigated for spectral efficiencies ranging from 2 to 7 bit/s/Hz. Computer simulation results indicate that BITCMs can achieve near‐capacity performance over Rayleigh fading channels, for all spectral efficiencies considered throughout the paper. It is also shown that the combination of turbo coding and rectangular QAM modulation with Gray mapping constitutes inherently a very powerful association, since coding and modulation functions are both optimized for operation in the same signal‐to‐noise ratio region. This means that no BER improvement is obtainable by employing any other signal constellation in place of the rectangular ones. Finally, the actual influence of the interleaving and mapping functions on error performance of BITCM schemes is discussed. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
95.
The muscle and brain creatine kinases of giant panda have been isolated and purified. The purified muscle and brain enzymes (MM and BB) are homogeneous on both the polyacrylamide gel electrophoresis in the presence and absence of SDS. Both enzymes are dimers, consisting of two identical subunits each with a molecular weight of 42,000 daltons. The characteristics of muscle and brain enzymes have been studied, respectively. The hybridized enzyme, MB, was prepared by hybridization of MM and BB. The kinetic parameters of MM, BB and MB were determined, respectively. The results from modification of SH groups show that the SH groups of panda creatine kinases are essential for their activity and among the all SH groups in the enzyme only one per subunit is essential for enzymatic activity. 相似文献
96.
J Alexander C Oseroff J Sidney P Wentworth E Keogh G Hermanson FV Chisari RT Kubo HM Grey A Sette 《Canadian Metallurgical Quarterly》1997,159(10):4753-4761
Transgenic mice expressing chimeric human (alpha1 and alpha2 HLA-A11 domains) and murine (alpha3, transmembrane, and cytoplasmic H-2Kb domains) class I molecules were derived. These mice were used as a model system to study the immunogenicity of human CTL epitopes and also to examine the aspects of Ag processing differences of mice vs man. Immunization of these mice with seven known HLA-A11-restricted CTL epitopes emulsified in IFA resulted in vigorous specific CTL responses. A larger panel of 45 A11-binding peptides was used to examine the relationship between immunogenicity in the HLA-A11/Kb transgenic mice and HLA-A11 binding capacity. Twenty-one of 28 (75%) peptides with high binding affinities (50% inhibitory concentration (IC50), 2-50 nM) and 7 of 13 (54%) intermediate binding peptides (IC50, 50-500 nM range) were immunogenic. In parallel, 19 of these peptides were used for in vitro primary immunizations of PBMC derived from HLA-A11 healthy human donors. It was found that 8 of 8 peptides that were able to elicit CTL in primary human in vitro cultures were also immunogenic in HLA-A11/Kb mice. Finally, HLA-A11/Kb transgenic mice were found to generate an A11/Kb restricted CTL response following immunization with influenza virus A/PR/8/34, suggesting that, at least to some extent, A11 epitopes are generated by transgenic mice as a result of natural in vivo processing and presentation. 相似文献
97.
98.
Heat-treatable aluminium alloys are known to suffer from severe loss of strength in the vicinity of welds. This investigation examines the structural effect of a reduced strength zone adjacent to the welds of cruciform connections and assesses its effects on the load carrying capacity, ductility and mode of failure. The results indicate that the load carrying capacity for short connection lengths are lower than values predicted with current methods of design and that the mode of failure is usually with a distinctive dish-like necking around the welded finger within the RSZ of the joint. 相似文献
99.
100.
Gaëtan Rimmelé Véronique Barlet-Gouédard Olivier Porcherie Bruno Goffé Fabrice Brunet 《Cement and Concrete Research》2008,38(8-9):1038-1048
Efficient and safe storage of injected supercritical carbon dioxide (CO2) underground is now one potential solution for reducing CO2 emissions in the atmosphere. Preventing any CO2 leakage through a wellbore annulus after injection is a key to maintaining long-term wellbore integrity. Most wells in depleted oil and gas fields may be re-used to inject CO2. These wells were mostly cemented with conventional Portland cement. It is thus crucial to study how such cement behaves at depth in CO2-rich fluids.Set cement samples are exposed to CO2 fluids under pressure and temperature to simulate downhole conditions. The degraded cement exhibits significant mineralogical changes and heterogeneous porosity distribution. The bulk porosity evolution, as well as local porosity gradients through the samples, is quantified using combined mercury porosimetry and back-scattered electron image analysis. Both techniques show an initial sealing stage related to calcium carbonate precipitation plugging the porosity, followed by a dissolution stage marked by a significant increase of porosity. 相似文献