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71.
72.
The settling rates and adsorption isotherms produced by a variety of suites of cationic polyelectrolytes in 3% kaolin suspensions were measured. Settling rates increased with molar mass even for low-mass, high-charge polymers. The very high settling rates produced by cationic copolymers of acrylamide decreased as the charge density of the polymer used increased. Hydrolysis of unbuffered polymers occurred over time and produced large changes in the effectiveness of the polymers. This is attributed to conformational changes. © 1994 John Wiley & Sons, Inc.  相似文献   
73.
Several samples of exhaust diesel soot are investigated by inverse gas chromatography and linear solvation energy relationship (LSER) modelling according to their soluble organic fraction content and their time of exposure in oxidative conditions. The results demonstrate the evolution of the adsorptive properties of the studied materials towards volatile compounds during the oxidation under NO2.  相似文献   
74.
To determine if the sexually dimorphic area (SDA) of the gerbil hypothalamus affects male sexual behavior through its projections to the retrorubral field (RRF) or ventrolateral periaqueductal gray (PAGvl), these pathways were lesioned asymmetrically. Unilateral radio frequency lesions of the lateral SDA (LSDA), the major source of the pathways, impaired mating when combined with contralateral RRF, but not PAGvl, lesions. N-methyl-{d}-aspartate (NMDA) lesions of the medial SDA, LSDA, and the area between them (the total pathway source) eliminated mating when combined with contralateral, but not ipsilateral, NMDA lesions of the RRF. To determine if A8 cells contributed to these effects, males received NMDA in the SDA and NMDA or 6-hydroxydopamine in the contralateral RRF. When combined with large SDA lesions, A8 lesions impaired but did not eliminate mating. Thus the SDA–RRF pathway, but not an SDA-A8 pathway, is essential for sexual behavior in male gerbils. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
Pooled time series is an underused analytic technique with the potential to increase researchers' ability to exploit clinical data. This article demonstrates the value of pooled time series by analyzing the behavior of youths in a specialized foster care treatment setting in response to a naturally occurring clinical event: changes in the number of youths living together in a treatment foster care setting. Pooled time series moves beyond typical clinical analyses with an increased capability of controlling statistically for complex within-S effects and with a clinically useful measure of effect size. The complexity of the intra-S data made it virtually impossible to determine the relevant significance (i.e., clinical meaning) of the clinical event by the use of standard n?=?1 visual analysis procedures or standard statistical methods (e.g., chi square). After things such as autocorrelation and individual time trends were statistically controlled, each additional youth increased the number of problematic behaviors by one behavior per youth per day on the Parent Daily Report. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
A boost type converter is described that is suitable for low-voltage DC-supply of fluorescent lamps. It has inherent lamp current limitation (ballast action) and provides the high voltage pulses and electrode heating that are required for igniting the lamp. The proposed circuit is applicable in automotive, emergency, and portable light sources.<>  相似文献   
77.
Is there a relationship between personality and criminal behavior? We addressed this question in a representative birth cohort of 862 male and female 18-yr-olds. Personality was assessed with the Multidimensional Personality Questionnaire (MPQ). The MPQ measures 10 relatively independent personality traits and was not designed to identify offenders. Delinquency was assessed via 3 data sources: self-reports, informant reports, and official records. Variable-centered analyses revealed that MPQ scales indexing negative emotionality and behavioral constraint were consistent predictors of delinquency across the 3 data sources. Person-centered analyses revealed that youths abstaining from delinquency were uniquely characterized by low interpersonal potency. Youths involved in extensive delinquency were uniquely characterized by feelings of alienation, lack of social closeness and risk taking. Advances in understanding criminal behavior can be made through research that places the personality-delinquency link in a developmental context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Investigators have concluded that excessive numbers of errors in test administration and scoring are routinely committed by both graduate students and practicing psychologists. Developing new methods for teaching assessment is viewed as a major means of improving competency. Unlike previous studies, this investigation examined the impact of both lecture and laboratory interventions designed to improve graduate student performance in assessment. Interventions consisted of weekly lecture quizzes and a variety of laboratory interventions. The results suggest that the interventions used can significantly improve students' lecture and laboratory performance when compared with controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
This study examines why people choose to self-disclose on "Donahue" and what role television plays in their lives prior to disclosure. Focused interviews were conducted with 29 informants between the ages of 12 and 68 who had appeared on the program. Analysis revealed that an evangelical fervor underpinned their decision, overshadowing other concerns about disclosure in a public forum. Informants generally reported low levels of television viewing. They held a pragmatic view of talk shows as avenues to reach a dual audience that included the mainstream public and members of their out-groups. Television disclosure is a tactic in a counterhegemonic struggle. Respondents utilized numerous impression management techniques in their efforts to manage their stigmatized status. Participants on "Donahue" risk co-optation, but running the gauntlet of criticism and ridicule allows an opportunity for delabeling rarely afforded to out-groups.  相似文献   
80.
Tension and vascular headache patients, initially treated with biofeedback and/or relaxation training in either a minimal therapist contact protocol (3 visits) or an intensive individual protocol (10 or 16 visits) were followed-up prospectively for 2 years. In the first study, for the first 6 months of follow-up, half of all patients continued to keep headache diaries and were seen monthly and the other half had only minimal contact. The results at 1-year follow-up, based on 4 weeks of daily headache diaries, revealed equally good maintenance from both treatment protocols and from both follow-up conditions. In Study 2, we found that patients remained improved over pretreatment baseline levels at the 2-year follow-up regardless of initial treatment intensity. Approximately three quarters of vascular patients who were initially improved at posttreatment remained improved at 2 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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