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1.
The conclusions clinicians have drawn about Holocaust survivors over the last 50 yrs differ sharply from researchers' findings. It is important to evaluate these discrepancies since different perceptions of survivors affect treatment approaches. The researchers' view, stressing the survivor's resilience and resourcefulness, contrasts with clinical impressions centering on a survivor syndrome involving deep emotional disturbances as residues of the Holocaust experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
McHale Susan M.; Kim Ji-Yeon; Whiteman Shawn; Crouter Ann C. 《Canadian Metallurgical Quarterly》2004,40(5):868
The authors studied sex-typing in the kinds (e.g., sports, handicrafts) and social contexts (same- vs. other-sex companions) of children's free time activities, and the links between sex-typed activities and gender development over 2 years. Participants were 200 White, working- and middle-class children (103 girls, 97 boys; mean age = 10.86 years). In annual home interviews, children rated their self-esteem, gender role attitudes and sex-typed personality qualities, academic interests, and school grades. During 7 nightly phone interviews each year, children reported on their activities. Boys were more sex-typed than girls in their peer activities, and children were least sex-typed in their activities with siblings. Sex-typed activities in middle childhood predicted individual differences in gender development in early adolescence (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
A dipole model is used to simulate incoherent Raman and fluorescent scattering by microspheres. The use of the addition theorem for spherical harmonics circumvents the need to evaluate double sums in the final formulas, thereby drastically reducing computational effort. Special attention is paid to consideration of backscattering geometry, which is important for lidar applications. The formulas derived for backscattering geometry decrease the computation time for size parameter x approdximately 100 by a factor of 200 compared with the time for calculations performed at other angles. 相似文献
4.
Inversion with regularization for the retrieval of tropospheric aerosol parameters from multiwavelength lidar sounding 总被引:1,自引:0,他引:1
Veselovskii I Kolgotin A Griaznov V Müller D Wandinger U Whiteman DN 《Applied optics》2002,41(18):3685-3699
We present an inversion algorithm for the retrieval of particle size distribution parameters, i.e., mean (effective) radius, number, surface area, and volume concentration, and complex refractive index from multiwavelength lidar data. In contrast to the classical Tikhonov method, which accepts only that solution for which the discrepancy reaches its global minimum, in our algorithm we perform the averaging of solutions in the vicinity of this minimum. This averaging stabilizes the underlying ill-posed inverse problem, particularly with respect to the retrieval of number concentration. Results show that, for typical tropospheric particles and 10% error in the optical data, the mean radius could be retrieved to better than 20% from a lidar on the basis of a Nd:YAG laser, which provides a combination of backscatter coefficients at 355, 532, and 1064 nm and extinction coefficients at 355 and 532 nm. The accuracy is improved if the lidar is also equipped with a hydrogen Raman shifter. In this case two additional backscatter coefficients at 416 and 683 nm are available. The combination of two extinction coefficients and five backscatter coefficients then allows one to retrieve not only averaged aerosol parameters but also the size distribution function. There was acceptable agreement between physical particle properties obtained from the evaluation of multiwavelength lidar data taken during the Lindenberg Aerosol Characterization Experiment in 1998 (LACE 98) and in situ data, which were taken aboard aircraft. 相似文献
5.
In this work the analysis of certain equilibrium problems in elasto-plasticity by the use of finite element techniques is considered. Variational inequalities are established. These characterise the stresses which minimise the total complementary energy, subject to the constraint that the stress satisfies the equilibrium and the yield conditions for materials having a continuous convex yield function. An exterior penalty formulation of this principle is presented, together with existence, uniqueness and convergence theorems. Some convergence criteria for certain types of finite element approximations of the penalised problem are given. Finally, a finite element method for the analysis of bending of elasto-plastic plates is described. Conditions for the convergence of this method are also proved using the methods of Hlavá?ek. 相似文献
6.
Brook Judith S.; Whiteman Martin; Brook David W.; Gordon Ann S. 《Canadian Metallurgical Quarterly》1981,17(6):841
Examined the interconnection of sets of paternal personality attributes, paternal socialization techniques, and adolescent personality factors with adolescent sons' use of marihuana. 246 male college students and their fathers participated in the study. Results of data from a battery of psychometric scales indicate that paternal personality attributes and socialization techniques were associated with the son's personality attributes, which in turn are related to his marihuana use. The findings provide evidence that paternal factors may either interact synergistically with or be mitigated by the son's personality attributes. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
David W Brook Judith S Brook Chenshu Zhang Martin Whiteman Patricia Cohen Stephen J Finch 《Nicotine & tobacco research》2008,10(8):1283-1291
The purpose of this study was to identify distinct trajectories of cigarette smoking from ages 14 to 32, and to examine adolescent personality factors that distinguish trajectories of smoking behavior. Participants (N = 975) were randomly selected and followed prospectively since 1975. Follow-up data on cigarette use and personality and behavioral attributes were collected at five points in time, using structured interviews given in private by trained interviewers. Of these subjects, 746 comprised the cohort used in this study. Growth mixture modeling identified five smoking trajectory groups: nonsmokers, occasional smokers, late starters, quitters, and heavy/continuous smokers. Adolescent personality and behavioral risk factors such as lower ego integration, more externalizing behavior, and lower educational aspirations distinguished the trajectory groups. No gender differences were noted. The findings supported the hypotheses indicating multiple distinct trajectory groups of smoking behavior. Smoking behavior appeared in early adolescence and most often continued into adulthood. Emotional difficulties (i.e., lower ego integration), externalizing behavior, and lower educational aspirations in early adolescence were associated both with smoking at an early age and with continuing to smoke into the thirties. To be more effective, smoking prevention programs should target personality and behavioral variations before smoking becomes habitual, particularly focused on characteristics reflecting behavioral problems as manifested in emotional difficulties, externalizing behavior, and low educational aspirations in early adolescence. The implications for research, prevention, and treatment are discussed. 相似文献
8.
The present study examined the role of perceived experience with an older child in mothers' expectations for subsequent children's adolescence as well as the impact of perceived experience with an older sibling on young adolescent children's expectations for their own adolescence. Participants were 305 sixth- and seventh-grade adolescents and 287 of their mothers. Participants were interviewed via telephone. For both mothers and children, the quality of experience with an older child/sibling was a better predictor of target-based expectations for the young adolescent than was the simple presence or absence of an older sibling. In some cases the link between quality of experience with an earlier born adolescent and mothers' expectations for the target child's adolescence was modified by the target child's temperament. In general, the results support a modeling hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
J. C. F. Millett N. K. Bourne N. T. Park G. Whiteman G. T. Gray III 《Journal of Materials Science》2011,46(11):3899-3906
The response of metallic materials to shock loading, like all loading regimes, is controlled largely by factors operating
at the microscopic or atomic levels. Over the past few years, face-centred cubic (fcc) metals have received a level of attention
where the role of features such as stacking fault energy and precipitation hardening have been investigated. We now turn our
attention to body-centred cubic (bcc) metals. In the past, only tantalum, tungsten, and their alloys have received significant
attention at high strain-rate conditions due to their use by the ordnance community. In particular, this investigation examines
the shear strength of these materials at shock loading conditions. Previous results on tantalum, tungsten, and a tungsten
heavy alloy are reviewed, and more recent experiments on niobium, molybdenum, and Ta–2.5 wt% W presented. Results are discussed
in terms of known deformation mechanisms and variations of Peierl’s stress. 相似文献
10.
On the basis of F. Heider's (1958) balance conceptions, a model was developed for specifying relations between the perceived properties of an act (its instrumentality and its consequentiality) and the intentionality attributed to the act. 129 1st-, 4th-, and 6th-graders made intentionality judgments of actions described in 10 pairs of stories, each pair made up of contrasting actions varying in instrumentality and/or consequentiality. The older Ss adhered more closely to the naive psychological model both in intentionality choice and in the reasons for their choice. The 1st-graders had more difficulty judging intentionality on the basis of an act's instrumentality as compared to its consequentiality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献