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951.
Recurring assessment problems in personality research related to the cross-situational consistency and predictability of behavior are evaluated in light of modern construct-oriented measurement theory. A recent study of the domain of conscientiousness behaviors (Mischel & Peake, 1982) is used to illustrate the consequences of not applying well-established strategies for the development and validation of psychological measures. It is argued that a careful specification of the behavioral exemplars of a trait domain and their interrelations is an essential precondition for the construct validity of a measure and for evidence of behavioral consistency. A reanalysis of the observational data of Mischel and Peake revealed conceptually and empirically identifiable facets of the domain of conscientiousness and, when behaviors were properly aggregated, substantial evidence of their construct validity and cross-situational generality. This finding is contrary to interpretations of Mischel and Peake and occurred despite several definitional and measurement problems identified in their study. Conditions contributing to the prediction of behavior across situations are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
952.
Alcoholics in treatment have demonstrated increased rates of HIV risk behavior and infection. This study explored individual and situational variables associated with HIV risk behaviors such as condom nonuse and sex with nonprimary partners reported during structured interviews of 802 male and female alcoholic inpatients. Logistic regression analyses indicated that person variables, sexual history variables, and situation variables were independently associated with sexual risk behavior in the most recent episode. Results of paired t tests revealed that participants who had engaged in sex with both primary and nonprimary partners during the previous 6 months reported significantly more frequent alcohol and condom use in situations involving sex with nonprimary partners. Prevention efforts need to target alcoholic inpatients as a group and, within this group, to focus on both high-risk individuals and high-risk situations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
953.
Kenrick Douglas T.; Baumann Donald J.; Cialdini Robert B. 《Canadian Metallurgical Quarterly》1979,37(5):747
Prior research has indicated that although negative mood-induction procedures reliably lead to enhanced helping in adults, such procedures do not produce increased helping in young children. Consistent with the negative state relief model, it was expected that, relative to neutral mood Ss, children in a negative mood would be more generous if the helping opportunity offered the potential for direct reward through social approval. This expectation was supported in a pair of studies wherein 149 1st–3rd graders were asked to imagine either neutral or sad experiences and were then given the opportunity to be charitable either in public or in private. Exp II provided evidence that the enhanced public helping of negative mood Ss is more parsimoniously interpreted as an attempt to remove negative mood than to repair public image. A 3-step account of the development of altruism as a self-reward is proposed. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
954.
955.
Jorenby Douglas E.; Keesey Richard E.; Baker Timothy B. 《Canadian Metallurgical Quarterly》1988,102(6):975
Although the excitatory effects of opiates have assumed greater importance in theories of compulsive drug use, the nature and time course of these effects remain unclear. The authors attempted to characterize the excitatory effects of morphine by administering doses of 5 mg/kg and 20 mg/kg in both warm and cold environments and by undertaking simultaneous assessments of core temperature, locomotor activity, and oxygen consumption. The results argue for a two receptor model to account for morphine's thermic effects: a high-affinity receptor that activates thermogenic systems, and a low-affinity receptor that mediates a poikilothermic response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
956.
Denney Douglas R.; Stephenson Laura A.; Penick Elizabeth C.; Weller Ronald A. 《Canadian Metallurgical Quarterly》1988,97(4):499
This study enumerated lymphocyte subclasses in the peripheral circulation of 15 patients with current diagnoses of major depressive disorder using monoclonal antibodies and flow cytometry. Depressed patients were found to have smaller numbers of helper (T4+), suppressor (T8+), and total T cells (T11+) relative to individually matched, normal controls, but no differences occurred between groups in the ratio of helper to suppressor cells. Furthermore, the helper, suppressor, and total T cell counts were found to be inversely related to patients' self-reported depression scores. The peripheral circulation of patients with major depression seems to be characterized by proportionately equal reductions in the numbers of helper and suppressor T cells, with the magnitude of these reductions being related to the severity of clinical depression among such patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
957.
Investigated variations in participation in a neighborhood-based educational support program in 35 18–39 yr old low-income and working-class White mothers of young children who were involved in 6 different parent groups for 1 yr. 30 other Ss had dropped out of participation during this period. Interview data were collected every 6 mo, and staff members kept records of attendance and telephone interactions with Ss. Program participation indices were attendance, relations with program peers, and use of staff services during the 1st 12 mo of involvement. Results show that 8 Ss were peer oriented, 8 Ss were staff oriented, 9 Ss demonstrated increased staff use, and 10 Ss had low involvement. Ss in the 1st 2 groups moved quickly to establish relationships, while Ss in the last 2 groups took a longer time to use program resources. Findings suggest a need for longitudinal measurement of the treatment in evaluation research, a conceptualization of intensive interventions as multidimensional, and the potential usefulness of focusing on interpersonal ties in an intervention program when measuring the treatment. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
958.
Guoan Li P. Ponte Casta eda A. S. Douglas 《Mechanics of materials : an international journal》1993,15(4):279-300
We study the effective constitutive response of composite materials made of rigid spheroidal inclusions dispersed in a ductile matrix phase. Given a general convex potential characterizing the plastic “in the context of J2-deformation theory” behavior of the isotropic matrix, we derive expressions for the corresponding effective potentials of the rigidly reinforced composites, under general loading conditions. The derivation of the effective potentials for the nonlinear composites is based on a variational procedure developed recently by Ponte Castaneda (1991a, J. Mech. Phys. Solids 39, 45–71). We consider two classes of composites. In the first class, the spheroidal inclusions are aligned, resulting in overall transversely isotropic symmetry for the composite. In the second class, the inclusions are randomly oriented, and thus the composite is macroscopically isotropic. The effective response of composites with aligned inclusions depends on both the orientation of the loading relative to the inclusions and on the inclusion concentration and shape. Comparing the strengthening effects of rigid oblate and prolate spheroids, we find that prolate spheroids give rise to stiffer effective response under axisymmetric “relative to the axis of transverse isotropy” loading, while oblate spheroids provide greater reinforcement for materials loaded in transverse shear. On the other hand, nearly spherical “slightly prolaterd spheroids are most effective in strengthening the composite under longitudinal shear. Thus, the optimal shape for strengthening composites with aligned inclusions depends strongly on the loading mode. Alternatively, the properties of composites with randomly oriented spheroidal inclusions, being isotropic, depend only on the concentration and shape of the inclusions. We find that both oblate and prolate inclusions lead to significant strengthening for this class of composites. 相似文献
959.
Describes a novel method of distributing a large number of digital video channels over a passive optical fibre network, while allowing the use of baseband binary receive equipment. The synchronous TDM is sampled, and receive channels are descrambled using a programmable delay-lock loop 相似文献
960.
MP Grassi M Borella F Clerici C Perin MT Bini A Mangoni 《Canadian Metallurgical Quarterly》1994,15(2):115-117
A case of reversible anterior bilateral opercular syndrome (Foix-Chavany-Marie syndrome) secondary to cerebral toxoplasma abscesses is described in a patient with AIDS. The symptoms regressed following antitoxoplasma and antiedema drug therapy. Although this is the first reported AIDS-related case, the syndrome is likely to recur in AIDS sufferers in whom multifocal cerebral lesions are common. 相似文献