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991.
Reviews the book, Strangers at the gate: The boat people's first ten years in Canada by Morton Beiser (1999). This book chronicles 10 years of research on the boat people since the arrival of 60,000 refugees from Vietnam, Laos, and Cambodia circa 1980. The data upon which most of the monograph is based are drawn from the Refugee Resettlement Project, which is a longitudinal study of a representative sample of 1,358 refugees. This book and the data it reports serve to challenge a number of popular misconceptions including: (1) Immigrants and refugees cause unemployment; (2) Immigrants and refugees overuse and put tremendous strain on the social welfare net; and (3) Immigrants and refugees bring crime and disease to Canada. The book also fairly examines important facts about Canada's racist immigration and social policies, past and present. This is an important book that warrants consideration in any efforts to explore the psychological aspects of Canadian culture and immigration studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
993.
Alteration in human platelet fatty acid levels with the consumption of fish oils containing eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) have been well documented, but changes in the fatty acid composition of plasma plasmalogenic phospholipid under similar circumstances have not been delineated. In the present study, subjects consumed the fish oil concentrate (MaxEPA) for 6 wk followed immediately by a 6-wk recovery period with no fish oil ingestion. Plasma total choline glycerophospholipid (GPC) and ethanolamine glycerophospholipid (GPE) subclasses isolated from blood samples obtained at 0, 3, 6, 9 and 12 wk of the experimental period were analyzed for fatty acid composition via thin-layer and gas-liquid chromatographic techniques. Consumption of fish oil for 3 or 6 wk significantly elevated the content of n-3 fatty acids while concomitantly decreasing n-6 fatty acid levels in plasma total GPC and in diacyl and alkenylacyl (plasmalogen) GPE. Alkenylacyl GPE exhibited the greatest alteration of both n-3 and n-6 fatty acid levels. Following 6 wk of supplementation with fish oil, EPA rose by 24.6 mol% in alkenylacyl GPE compared to increases of 6.7 and 7.1 mol% in diacyl GPE and total GPC, respectively. The increase in EPA (from 5.0 to 29.6 mol%) in plasma alkenylacyl GPE represents amongst the highest enrichment of EPA in any lipid yet reported in human subjects. DHA also rose by 8.0, 4.8, and 3.1 mol% in alkenylacyl GPE, diacyl GPE, and total GPC, respectively. Alkenylacyl GPE exhibited the greatest mol% decline (by 18.7 mol%) in arachidonic acid (AA, 20:4n-6) following 6 wk of fish oil supplementation. The corresponding decreases of AA in diacyl GPE and total GPC were 8.7 and 1.8 mol%, respectively. Following the 6 wk recovery period, n-3 and n-6 fatty acid levels had returned to pre-supplementation values. The marked enrichment of alkenylacyl GPE in n-3 fatty acids, especially EPA, may be of significance with respect to a unique role for this plasma phospholipid subclass in attenuating certain lipoprotein-mediated cardiovascular effects as observed with fish/fish oil consumption.  相似文献   
994.
Composite thin films of molybdenum disilicide-silicon carbide (MoSi2-SiC) have been deposited via rf magnetron sputtering onto molybdenum substrates. An intermediate layer was deposited in the presence of nitrogen gas and evaluated as a potential diffusion barrier layer. The composite films have been characterized using X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, and Auger electron spectroscopy. The as-deposited films were amorphous but crystallized into nanometer-sized grains after annealing under vacuum at 1000°C for 30 min. There was a significant amount of interdiffusion between the film and substrate, which resulted in the formation of subsilicides such as Mo5Si3 and MoSi3, as well as Mo2C. The films that were deposited via reactive sputtering in a nitrogen ambient were amorphous in both the as-deposited and annealed conditions. Significantly fewer second phases were detected with the presence of the intermediate layer, which suggests the potential use of the nitrided (MoSi x N y C z ) layer as a high-temperature diffusion barrier layer for the silicon and carbon.  相似文献   
995.
This study examined memory for emotional material, endorsement of emotional adjectives, and negative attributional style (NAS) in seasonal affective disorder (SAD). SAD patients showed elevated NAS and increased endorsement of negative self-referent adjectives, but no memory bias for negative material, when compared with never-depressed controls. Longitudinal analyses revealed that none of these cognitive measures significantly predicted later symptom levels independent of initial symptom levels, in the SAD patients. The cross-sectional findings for adjective endorsement and memory were replicated in a second experiment. These data provide further evidence that depression-related memory effects in SAD are different from those found in nonseasonal depression. Accounts of these differences involving putative mood-repair processes and/or an absence of dysfunctional negative schemas in SAD are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
In recent years, environmental awareness and legislation have focused public attention on vehicle emissions. Consequently, more research has been devoted to emissions and pollution by lubricants. A number of studies has been carried out to understand lubricant-related emissions and leak rates as well as the effects on fuel economy of using low viscosity grades of lubricant. The purpose of the present investigation was to develop for use in gasoline and diesel engines a crankcase lubricant which contained improved performance in engine cleanliness with fuel economy and a low rate of particle emissions. Emphasis was placed on low toxicology and rapid biodegradability because of the risk of unintentional emissions. Such a sophisticated lubricant is desirable not only for normal road vehicles but also and especially for use in ecologically sensitive areas. During the development of this lubricant, numerous laboratory tests were performed. In order to assess the quality and the fuel economy of the new lubricant, tests were carried out on an engine test rig and on a vehicle test bench. Field tests were run with various vehicles and stationary engines, using different fuel types. Unleaded gasoline, diesel fuels with a varying sulphur content, and rape seed oil methyl ester (RME) were used. This paper summarises the results of this investigation.  相似文献   
997.
This research examined how group processes alter the impact of alcohol on a judgment task requiring vigilance. The authors compared two competing explanations, deindividuation and group monitoring, for the possible effects of alcohol. Two hundred and eighty-six undergraduates with normal drinking habits undertook a vigilance task alone or in four-person groups having consumed either alcohol (calculated to achieve up to .08 blood alcohol content) or a placebo. The vigilance task required them to count occurrences of the word "the" in a spoken passage. Alcohol significantly impaired the performance of individuals but not groups. Group members performed at a similar level in both conditions, making fewer errors than individuals in the alcohol condition. The fit of different decision-making models were tested. In both the alcohol and placebo conditions, group consensus was predicted by processes consistent with the group monitoring hypothesis. The evidence highlights that under certain conditions, group process can compensate for the cognitively impairing effects of alcohol on individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
Describes a conference convened to explore problems and issues in training psychologists to serve Asian Americans and their communities and to provide a setting for administrators, faculty, practitioners, and students to share perspectives on the mental health needs of Asian Americans. Among the outcomes were recommendations concerned with appropriate models and approaches of psychology for Asian Americans and appropriate training of psychologists for Asian-American communities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
As a result of mental health disparities between White and racial/ethnic minority clients, researchers have argued that some therapists may be generally competent to provide effective services but lack cultural competence. This distinction assumes that client racial/ethnic background is a source of variability in therapist effectiveness. However, there have been no direct tests of the therapist as a source of health disparities. We provided an initial test of the distinction between general and cultural competence by examining client racial/ethnic background as a source of variability in therapist effectiveness. We analyzed cannabis use outcomes from a psychotherapy trial (N = 582) for adolescent cannabis abuse and dependence using Bayesian multilevel models for count outcomes. We first tested whether therapists differed in their effectiveness and then tested whether disparities in treatment outcomes varied across therapist caseloads. Results suggested that therapists differed in their effectiveness in general and that effectiveness varied according to client racial/ethnic background. Therapist effectiveness may depend partially on client racial/ethnic minority background, providing evidence that it is valid to distinguish between general and cultural competence. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
1000.
The major outer surface protein, OspA, of Borrelia burgdorferi is a lipoprotein which is a particular interest because of its potential as a vaccine candidate. However, serotypic and genetic analysis of OspA from both European and North American strains have demonstrated antigenic and structural heterogeneities. We purified OspA to homogeneity by exploiting its resistance to trypsin digestion. By treating spirochetes with trypsin and then using Triton X-114 extraction and ion-exchange chromatography, we obtained a yield of 2 mg of pure OspA protein per liter of culture. INtrinsic labeling with [14C]palmitic acid confirmed that OspA was lipidated, and partial digestion established lipidation at the amino-terminal end of the molecule. The reactivity of five anti-OspA murine monoclonal antibodies to nine different isolates of B. burgdorferi was ascertained by Western blot (immunoblot) analysis. Purified OspA was fragmented by enzymatic or chemical cleavage, and the monoclonal antibodies were able to define four distinct immunogenic domains. Further resolution of the epitope specificity to determine humoral and cellular immune responses to OspA has implications for vaccine development and for the utility of this protein as a reagent in diagnostic testing for Lyme borreliosis.  相似文献   
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