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71.
Historical representations explicitly depicting Blacks as apelike have largely disappeared in the United States, yet a mental association between Blacks and apes remains. Here, the authors demonstrate that U.S. citizens implicitly associate Blacks and apes. In a series of laboratory studies, the authors reveal how this association influences study participants' basic cognitive processes and significantly alters their judgments in criminal justice contexts. Specifically, this Black-ape association alters visual perception and attention, and it increases endorsement of violence against Black suspects. In an archival study of actual criminal cases, the authors show that news articles written about Blacks who are convicted of capital crimes are more likely to contain ape-relevant language than news articles written about White convicts. Moreover, those who are implicitly portrayed as more apelike in these articles are more likely to be executed by the state than those who are not. The authors argue that examining the subtle persistence of specific historical representations such as these may not only enhance contemporary research on dehumanization, stereotyping, and implicit processes but also highlight common forms of discrimination that previously have gone unrecognized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
The present study investigated the role of endogenous opioids in the expression of defensive behaviors (DBs) and the suppression of cell proliferation (CP) in the dentate gyrus (DG) induced by exposure to predator odor, trimethyl thiazoline (TMT). Adult male rats were injected with either naltrexone (an opioid antagonist, 5 mg/kg) or saline 30 min before exposure to either TMT or a control odor. Behavior was scored for the first 15 min of odor exposure. Bromodeoxyuridine (BrdU, 200 mg/kg) was then injected, and the rats were perfused 1 hr later. Exposure to TMT increased the expression of DBs and suppressed the number of proliferating cells in the DG. Pretreatment with naltrexone attenuated the effects of TMT on DB expression but did not attenuate the effects of TMT on CP. In addition, naltrexone administration suppressed CP in the absence of TMT. These results demonstrate a dissociation between DBs and regulation of CP in the DG. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
74.
The fabrication process for a novel carbon fiber-reinforced polymer (polyamide 12) composite femoral stem using inflatable bladder molding was studied. Effect of processing temperature, holding time and applied internal pressure on the consolidation quality of the composite was investigated. Consolidation quality was evaluated by density and void content measurements and scanning electron microscope analysis. As expected, void content (porosities) and presence of large resin pockets were found to increase for lower processing temperature, holding time and applied pressure. Crystallinity as well as melting temperatures measured using differential scanning calorimetry could be related to molding conditions. A progressive reduction of the previous thermal history (crystalline peak of neat composite) and an increase in crystallinity were obtained for higher molding temperature. Static compression testing with void content analysis of molded specimens was used to determine optimal molding conditions. The composite structure molded showed compressive modulus close to cortical bone’s. Compression load at failure of composites molded in optimal conditions were found to be three times higher than those of femoral bone for jumping on one leg or 10 times those for normal gait. The molded composite structure appears to be an excellent candidate for femoral stems used in total hip arthroplasty.  相似文献   
75.
Meta-analytic procedures were used to examine data from 83 field studies of the Productivity Measurement and Enhancement System (ProMES). The article expands the evidence on effectiveness of the intervention, examines where it has been successful, and explores moderators related to its success. Four research questions were explored and results indicate that (a) ProMES results in large improvements in productivity; (b) these effects last over time, in some cases years; (c) the intervention results in productivity improvements in many different types of settings (i.e., type of organization, type of work, type of worker, country); and (d) moderator variables are related to the degree of productivity improvement. These moderator variables include how closely the study followed the original ProMES methodology, the quality of feedback given, whether changes were made in the feedback system, the degree of interdependence of the work group, and centralization of the organization. Implications based on these findings are discussed for future use of this intervention, and the system is discussed as an example for evidence-based management. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
On the basis of recent evidence suggesting that gay men are particularly likely to fear interpersonal rejection, the authors set out to extend the rejection sensitivity construct to the mental health concerns of gay men. After establishing a reliable and valid measure of the gay-related rejection sensitivity construct, the authors use this to test the mediating effect of internalized homophobia on the relationship between parental rejection of one's sexual orientation and sensitivity to future gay-related rejection. The present data support this mediational model and also establish rejection sensitivity's unique contribution to unassertive interpersonal behavior in the context of internalized homophobia and parental rejection. The authors conclude that gay-related rejection sensitivity is a useful construct for clinicians working with gay men given the impact that past gay-related rejection can have on their gay clients' present cognitive-affective-behavioral functioning. The authors discuss the possibility of revising rejection-prone schemas in clinical work with gay men. Future research is necessary to further examine the internal processing and interpersonal functioning of gay men by using existing constructs (or modifications of them) that are likely to be particularly relevant to the unique concerns of this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
This study examined whether the distribution of tobacco use and related psychosocial risk factors among youth in urban India vary by socioeconomic status (SES). Data were derived from a cross-sectional survey of students enrolled in the 6th and 8th grades in 32 schools in Delhi and Chennai (N = 11,642). The survey was conducted in 2004, before the implementation of a program designed to prevent and reduce tobacco use (MYTRI). Mixed-effect regression models were used (a) to determine the prevalence of tobacco use among private (higher SES) and government (lower SES) school students, (b) to investigate whether certain psychosocial factors were associated with increased tobacco use, and (c) to determine how these factors varied by school type. Ever-use of multiple forms of tobacco (e.g., gutkha, bidis, and cigarettes) was more prevalent among government school students than private school students. After adjusting for city, gender, grade, and age, we found the prevalence rate for ever-use of any tobacco product to be 18.9% for government school students, compared with 12.2% for private school students (p<.01). Students in government schools scored lower than private school students on most psychosocial risk factors for tobacco use studied here, indicating higher risk. Government school students scored the lowest for refusal skills, self-efficacy, and reasons not to use tobacco. Social susceptibility to chewing tobacco and social susceptibility to smoking were strong correlates of current tobacco use among government school students. Exposure to tobacco advertising was also a strong correlate of current tobacco use for government school students but not private school students. In two large cities of India, students attending government schools are using many forms of tobacco at higher rates than private school students. The psychosocial risk profile of government school students suggests they are more vulnerable to initiation and use and to outside influences that encourage use.  相似文献   
78.
Mediation is a growing alternative to the adversarial settlement of divorce disputes that is part of a broader movement toward the private ordering of divorce. Problems with the indeterminant "best interests" standard and evidence from psychological research make mediation particularly appealing for settling child-custody disputes. Although some encouraging evidence is available on diversion of disputes from courts and consumer satisfaction with mediation, there is a considerable need for further research. Moreover, a number of practical, legal, and ethical questions about mediation remain unanswered. Psychologists can play a vital role in systematically evaluating divorce mediation and in shaping policy in regard to its practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
The waste of inedible parts of pineapple, particularly in tropical countries, contributes to environmental burden. This study aimed to utilize pineapple stem waste as a source of starch-based pharmaceutical excipient. The starch was isolated from pineapple stem waste using a simple process without applying harsh chemicals. The isolated starch (PSS) was then physically modified through gelatinization and spray drying to improve its physical properties. Starch characteristics were identified by FTIR, TGA, and XRD analysis. The SEM imaging showed morphological change with reduced surface roughness due to physical modification of the starch. Decreased crystallinity of modified starch (MPS) was confirmed by our XRD results: the peaks of A-type crystalline at 2θ of 13°, 15°, 18°, and 23° were present in PSS, yet mostly absent in MPS. Thermogravimetric analysis showed that MPS behaved differently from PSS and the degradation events occurred at lower temperature. When the starch was spray-dried without prior gelatinization process, the physicochemical characteristics of spray-dried starch resembled untreated starch. Moisture content in PSS (10.66%) decreased after gelatinization to 7.3%. Potential use of MPS was demonstrated by its powder flowability (Student’s t test, p?<?0.05), swelling capacity (Student’s t test, p?<?0.05), and compaction profile. In summary, our findings demonstrated that modified pineapple starch showed better physical characteristics and quite promising as a tablet binder and disintegrant.  相似文献   
80.
The subunit structure of human macrophage migration inhibitoryfactor (MIF) has been studied by preliminary X-ray analysisof wild-type and selenomethionine-MIF and dynamic light scattering.Crystal form I of MIF belongs to space group P212121 and isgrown from 2 M ammonium sulfate at pH 8.5. A native data sethas been collected to 2.4 Å resolution. Self-rotationstudies and Vm values indicate that three molecules per asymmetricunit are present A data set to 2.8 Å resolution has beencollected for crystal form II, which belongs to space groupP3121 or P3221 and grows from 2 M ammonium sulfate, 2% polyethyleneglycol (average molecular mass 400), 0.1 M HEPES, pH 7.5. Three,four, five or six monomers in the asymmetric unit are consistentwith Vm values for this crystal form. Analysis of crystal formII containing selenomethionine-MIF indicates nine selenium sitesare present per asymmetric unit. Dynamic light scattering ofMIF suggests that the major form of the protein in solutionis a trimer. The results of these studies are in contrast toprevious reports indicating that MIF is a monomer or dimer.The subunit arrangement of MIF is similar to that of tumor necrosisfactor and suggests that signal transduction might require trimerizationof receptor subunits.  相似文献   
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