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本文是美国芝加哥艺术学院教授埃尔金斯(James Elkins)与美国芝加哥艺术学院教授蒋奇谷及几位艺术家关于当代艺术和水墨画的对话与交流.  相似文献   
3.
Physiological compliance (PC) refers to the correlation between physiological measures of team members over time. The goals of this study were to examine ways of measuring PC in heart rate variability (HRV) data and the relationship between PC and team performance. Teams were tasked with entering both real and simulated rooms and “shooting” individuals with a weapon and identifying individuals without a weapon. The linear correlation and directional agreement PC methods were shown to be the most sensitive to differences in performance, with greater PC being associated with better performance. The correlation method when applied to a measure of respiratory sinus arrhythmia (RSA) revealed a significant difference between high and low performers (t[8] = −2.31, p = 0.03) and the directional agreement applied to inter-beat-intervals and RSA revealed trend-level differences (t[4.62] = −1.86, p = 0.06 and t[8] = −1.68, p = 0.07). These results suggest that PC may have merit for predicting team performance.  相似文献   
4.
The authors discusses the effects of switching low inductive currents with 138 kV SF6 breakers in a petrochemical plant. Switching transients are believed to have contributed to the failure of a 13.8 kV PT and a 13.8 kV air magnetic circuit breaker. The high-frequency transient surge can transfer across a transformer due to transformer capacitances between the high- and low-voltage windings. The electromagnetic transient program system (ETPS) model and different case studies are discussed with the effect of different transformer winding capacitances. The interruption mechanism of low inductive currents is also described. This analysis demonstrates the need to conduct switching transient studies and the need for surge arresters on transformer secondary terminals under certain system conditions  相似文献   
5.
C Elkins  K Graf 《Canadian Metallurgical Quarterly》1996,16(3):114; quiz 114-114; quiz 115
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6.
Examines some of the more frequent concerns and criticisms about rational–emotive therapy, including issues of relationship factors, emotive aspects, values, religious concerns, and intervention techniques and styles in therapy. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c2 = .51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Gaussian field expansions for circular aperture antennas are reviewed, and a method for finding optimal scales in these expansions is given, paralleling the method for rectangular antennas presented in an earlier paper. This procedure is shown to lead to approximations structured in the sense that the number of lobes in the approximation corresponds to the number of terms retained in the expansion. An example is given of the development of a cosine distribution from the aperture, through the Fresnel region, to the far field.  相似文献   
9.
The viral accessory protein Vpx is required for productive in vitro infection of macrophages by simian immunodeficiency virus from sooty mangabey monkeys (SIV(SM)). To evaluate the roles of Vpx and macrophage infection in vivo, we inoculated pigtailed macaques intravenously or intrarectally with the molecularly cloned, macrophage tropic, acutely pathogenic virus SIV(SM) PBj 6.6, or accessory gene deletion mutants (deltaVpr or deltaVpx) of this virus. Both wild-type and SIV(SM) PBj deltaVpx viruses were readily transmitted across the rectal mucosa. A subsequent 'stepwise' process of local amplification of infection and dissemination was observed for wild-type virus, but not for SIV(SM) PBj deltaVpx, which also showed considerable impairment of the overall kinetics and extent of its replication. In animals co-inoculated with equivalent amounts of wild-type and SIV(SM) Pbj deltaVpx intravenously or intrarectally, the deltaVpx mutant was at a strong competitive disadvantage. Vpx-dependent viral amplification at local sites of initial infection, perhaps through a macrophage-dependent mechanism, may be a prerequisite for efficient dissemination of infection and pathogenic consequences after exposure through either mucosal or intravenous routes.  相似文献   
10.
The dynamics of plasma viremia were explored in a group of 12 simian immunodeficiency virus (SIV)-infected rhesus macaques (Macaca mulatta) that had received prior immunization with either nonrecombinant or trivalent (gag-pol, env) SIV-recombinant vaccinia viruses. Three distinct patterns of viral replication observed during and following primary viremia accounted for significant differences in survival times. High-level primary plasma viremia with subsequently increasing viremia was associated with rapid progression to AIDS (n = 2). A high-level primary plasma virus load with a transient decline and subsequent progressive increase in viremia in the post-acute phase of infection was associated with progression to AIDS within a year (n = 6). Low levels of primary plasma viremia followed by sustained restriction of virus replication were associated with maintenance of normal lymphocyte subsets and intact lymphoid architecture (n = 4), reminiscent of the profile observed in human immunodeficiency virus type 1-infected long-term nonprogressors. Three of four macaques that showed this pattern had been immunized with an SIV recombinant derived from the attenuated vaccinia virus, modified vaccinia virus Ankara. These data link the dynamics and extent of virus replication to disease course and suggest that sustained suppression of virus promotes long-term, asymptomatic survival of SIV-infected macaques. These findings also suggest that vaccine modulation of host immunity may have profound beneficial effects on the subsequent disease course, even if sterilizing immunity is not achieved.  相似文献   
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