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41.
Developmental research is reviewed to evaluate how race, ethnicity, racial identity, and ethnic identity are defined and investigated for minority populations. First reviewed is how these terms are used in developmental and counseling research. Early practices limited these terms to their demographic denotations (e.g., heritage), but more recent practices have expanded to include socially constructed connotations. Second, developmental research was used to evaluate key assumptions in theories of racial and ethnic identity development, with an emphasis on recent longitudinal studies. Research supports some, but not all, of these developmental predictions. Longitudinal research supported the progressive nature of ethnic and racial identity development and that exposure to racism appears to stimulate further identity development during adolescence. In contrast, available evidence does not support the claims of a developmental hierarchy for racial ideologies and that identity crises are normative. Adjustment was not predicted by a single racial or ethnic identity ideology, but research suggested that the adolescent's sociocultural identity and socialization should be tailored to the nature of the racial and ethnic context for development. Implications for counseling research and practice are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Nestor Paul G.; Faux Steven F.; McCarley Robert W.; Penhune Virginia; Shenton Martha E.; Pollak Seth; Sands Stephen F. 《Canadian Metallurgical Quarterly》1992,101(4):682
M. I. Possner's 1980 reaction time (RT) paradigm was used to examine the engagement and disengagement operations of visual selective attention in patients with schizophrenia. In the 1st experiment 14 medicated, chronic schizophrenic Ss (diagnosed by criteria of the Diagnostic and Statistical Manual of Mental Disorders [DSM-I]), and 15 age-matched normal and control Ss made a speeded response to a target preceded by a valid, and invalid, or no cue. Control Ss showed the expected advantage and disadvantage in RT for valid and invalid cues, which suggests intact engagement and disengagement operations. For schizophrenic Ss, valid cues also enhanced RT, but invalid cues did not slow RT. Similar results were found in the 2nd experiment. The failure of unpredictable, invalid cues to inhibit RT in chronic schizophrenia may be related to an abnormality in the disengagement operation of selective attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Burns John W.; Kubilus Amanda; Bruehl Stephen; Harden R. Norman; Lofland Kenneth 《Canadian Metallurgical Quarterly》2003,71(1):81
Changes in maladaptive cognitions may constitute therapeutic processes of multidisciplinary pain programs. A cross-lagged panel design was used to determine whether (a) early-treatment cognitive change predicted late-treatment outcome index change, but not vice versa; and (b) these effects remained significant with depression change controlled. Ninety chronic pain patients, in a 4-week multidisciplinary program, completed measures of catastrophizing, pain helplessness, depression, pain, interference, and activity level at pre-, mid-, and posttreatment. With depression changes controlled, early-treatment catastrophizing and pain helplessness changes predicted late-treatment outcome index changes, but not vice versa; early-treatment depression changes predicted late-treatment activity changes, but not vice versa. Findings advance understanding of pain treatment process and suggest that negative cognition changes may indeed affect improvements in treatment outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Stephen Dain 《Color research and application》2007,32(6):428-432
There are anecdotal reports of color vision deficient medical practitioners (particularly deuteranopes) having difficulty in recognizing cyanosis. An understanding of the color changes in oxygenated blood has led to a better understanding of the lighting needs for hospitals. Using the same database, this article investigates the propensity for color vision deficient observers to make mistakes with cyanotic patients. The possibilities for helping the observer with appropriate color of lighting are considered. The spectral reflectances of blood at varying oxygenation levels previously reported were used 7 ; 8 to calculate chromaticity and lightness. The direction of the chromaticity change was compared with the protanopic and deuteranopic confusion lines. An attempt was made to identify sources that enhanced color changes for the color deficient. The color change of blood oxygenation is closely aligned with the confusion lines of congenital dichromats (particularly protanopia) showing the potential for difficulty in making this decision. No source could be demonstrated to solve the problem or even reduce it significantly. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 428–432, 2007 相似文献
47.
Exp I, with 12 male hooded rats, demonstrated that Ss with caudate-putamen lesions exhibited an impairment in the acquisition and reversal of a spatial maze task when compared with unoperated control Ss. Exp II, with 24 Ss, investigated leverpress responding supported by a VI schedule in 3 groups of Ss: a group with caudate-putamen lesions, a group with lesions of the posterior cortex, and an unoperated control group. The presentation of a 0.5-sec, response-contingent light correlated with reinforcement generated an elevated response rate in the 2 operated groups but tended to suppress responding in the control group, perhaps by overshadowing the response–reinforcer relation. Only the group with cortical lesions maintained the elevated rate when the light was uncorrelated with food delivery. Exp III confirmed for these same Ss that caudate-putamen lesions produced a spatial learning deficit. No deficit was observed in the posterior cortex group. It is suggested that caudate-putamen lesions disrupt the mechanism underlying the response–reinforcer association on which spatial maze learning and free operant responding in part depend. (48 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Previous research indicates that tobacco craving predicts relapse to smoking among adult smokers attempting to quit. We hypothesized a similar relationship between craving and lapse (any smoking following a period of abstinence) among adolescent smokers during the treatment phase of a clinical trial. A visit was considered a lapse visit if the participant reported smoking or had a carbon monoxide level of 7 ppm or greater subsequent to an abstinent visit. A total of 34 participants (mean age = 14.9 years [SD = 1.3]; mean cigarettes/day = 18.0 [SD = 7.6]; mean Fagerstr?m Test for Nicotine Dependence score = 6.8 [SD = 1.34]; 65% female), were included in the present analysis of 167 treatment visits. Logistic regression analyses showed a positive relationship between degree of craving, measured by the Questionnaire on Smoking Urges, and lapse during smoking cessation treatment (p = .013). Additionally, linear regression analyses demonstrated a strong positive association between cigarettes smoked per day and craving scores (p<.001). Taken together with other data, these findings suggest that degree of craving might influence tobacco abstinence for adolescent smokers. Thus monitoring and addressing craving appears useful to increase the success of adolescent smoking cessation. 相似文献
49.
Stephen J. Spells 《Polymer》1985,26(13):1921-1928
The chain conformation of solution-crystallized polyethylene has previously been confirmed by infra-red spectroscopy, using the CD2 bending bandshape for samples with a minority of the deuterated species1–3. The method of calculating the i.r. band profile from molecular conformational models is now developed to give a more accurate representation of doublet splittings and to include the singlet component. The CH2 bending profile is calculated for samples with a deuterated matrix, and the good agreement with experimental data indicates that the same molecular model is applicable for samples with the deuterated polymer as either guest or matrix, for identical crystallization conditions. This result implies that isotopic fractionation is unimportant under these conditions. 相似文献
50.
Stephen Shaoyi Liao Huai Qing Wang Qiu Dan Li Wei Yi Liu 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(3):660-671
This paper presents a new method for learning Bayesian networks from functional dependencies (FD) and third normal form (3NF) tables in relational databases. The method sets up a linkage between the theory of relational databases and probabilistic reasoning models, which is interesting and useful especially when data are incomplete and inaccurate. The effectiveness and practicability of the proposed method is demonstrated by its implementation in a mobile commerce system. 相似文献