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排序方式: 共有877条查询结果,搜索用时 46 毫秒
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Michael J Zvolensky Laura E Gibson Anka A Vujanovic Kristin Gregor Amit Bernstein Christopher Kahler C W Legues Richard A Brown Matthew T Feldner 《Nicotine & tobacco research》2008,10(8):1415-1427
The present investigation examined whether daily smokers with posttraumatic stress disorder (PTSD), as compared to daily smokers with either anxiety psychopathology or no current Axis I psychopathology, have decreased success in the early phases of a self-guided smoking quit attempt. Participants were 140 daily smokers (81 women; M (age) = 29.5; SD = 11.9; range = 18-65 years); approximately one-third of the sample met criteria for current PTSD (n = 47), one-third met criteria for other current anxiety disorders (without PTSD; n = 33), and one-third did not meet criteria for any current Axis I disorder (n = 60). Consistent with prediction, membership in the PTSD group, compared to membership in the other anxiety disorders group and the group with no current Axis I psychopathology, was associated with increased risk of lapse during the first week following quit day. Additionally, daily smokers with PTSD and other anxiety disorders were at significantly increased risk of relapse during the first week post-cessation compared to persons without Axis I psychopathology. However, the PTSD group and the other anxiety disorders group did not differ from one another in terms of relapse. Results suggest that PTSD is associated with increased risk of smoking lapse and relapse compared to smokers with no current Axis I psychiatric problems, and increased risk of early smoking lapse but not relapse, as compared to those with other anxiety disorders. Findings provide novel evidence that PTSD, and perhaps anxiety disorders more generally, may be important factors in reducing the odds of successful unaided quit attempts in the early phases of cessation. 相似文献
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In this paper, we formulate robust stability and performance bounds in terms of guaranteed cost inequalities. We derive new guaranteed cost bounds for plants with real structured uncertainty, and we reformulate them as linear matrix inequalities (LMIs). In particular, we obtain a shifted linear bound and a shifted inverse bound, and give LMI forms for a shifted bounded real bound, a shifted Popov bound, a shifted linear bound and a shifted inverse bound. Several examples are used to compare the shifted bounds with their unshifted counterparts and to make comparisons among these new bounds and vertex LMI bounds. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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The results of a study performed on crosslinked polyethylene (XLPE) insulated cables tested in the laboratory under accelerated conditions are described. URD-type cables rated at 15 kV were aged at 60 Hz, 6 kV/mm, (150 V/mil) and load cycled daily to 90°C conductor, with water inside the pipe and outside of the samples, for periods of up to 3 years. DC testing was performed before and during the aging. An anticipated significant reduction in the AC breakdown strength is observed in control cables (not DC tested), from 44 kV/mm (1100 V/mil) for unaged cables, to 10 kV/mm (250 V/mil), for aged cables. However, there was no further reduction in the AC breakdown strength of cables subjected to DC testing as compared to those that are not tested with DC. It is concluded that AC breakdown strength is not an effective diagnostic tool for determining the effect of DC testing of URD cables aged under the conditions described 相似文献
66.
Robert Bernstein 《Software》1986,16(7):641-652
Methods are given for finding a sequence of ‘add’, ‘subtract’ and ‘shift’ instructions to multiply the contents of a register by an integer constant. Each method generalizes the previous one and requires only a few intermediate or scratch registers. A variation of the last method is used in the PL.8 compiler and uses an unnoticeable amount of the overall compile time. Some statistics roughly indicating the effectiveness of the methods are presented. 相似文献
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A group of rhesus monkeys, consisting of 8 matrilines of up to 4 generations each and 9 unrelated adult males, was studied for 2 yrs. Group size varied between 75 and 91 individuals. Data collection consisted of ad lib recording of agonistic interactions. Results indicate that adult male interference in agonistic episodes was strongly biased against adolescent and adult male participants, whereas adult female interference was biased in favor of kin and in support of younger animals against older animals. Although natal males also were biased in favor of their kin, their selective targeting of sexually mature males was independent of kinship. Adolescent males targeted adult males, but only in defense of kin. It is suggested that this selective interference against adolescent and adult males by adult males has the potential to profoundly modify male agonistic participation in intragroup encounters after puberty. Because female support is influenced primarily by kinship, females less consistently interfere against male agonistic participants. Adult males may therefore play an important role in the socialization of male agonistic expression. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Grady Cheryl L.; Bernstein Lori J.; Beig Sania; Siegenthaler Amy L. 《Canadian Metallurgical Quarterly》2002,17(1):7
Age-related differences in brain activity mediating face recognition were examined using positron emission tomography. Participants encoded faces using a pleasant-unpleasant judgement, a right-left orientation task, and intentional learning. Scans also were obtained during recognition. Both young and old groups showed significant effects of encoding task on recognition accuracy, but older adults showed reduced accuracy overall. Increased brain activity in older adults was similar to that seen in young adults during conditions associated with deeper processing, but was reduced during the shallow encoding and recognition conditions. Differential correlations of brain activity and behavior were found that suggest older adults use unique neural systems to facilitate face memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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