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Effects of the muscarinic antagonist scopolamine on lordosis, solicitation, pacing, approach, attractivity, and activity were evaluated in ovariectomized rats brought into sexual receptivity with estrogen and progesterone. Systemic (1 mg/rat) or intraventricular (10 μg bilaterally) administration of scopolamine significantly reduced the incidence of lordosis and solicitation behaviors and disrupted typical pacing of sexual contacts with a stimulus male. In addition, females avoided contact with a stimulus male, but not a stimulus female, following intraventricular infusion of scopolamine. The levels of general activity and frequencies of sexual contacts were similar in females treated intraventricularly with scopolamine and vehicle solutions. Consequently, scopolamine disrupted various components of sexual behavior, including lordosis, solicitation, pacing, and approach, without altering female attractivity or general activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Behavioral treatments for obesity seek to modify eating and exercise behaviors by a change in their antecedents and consequences. More direct modification of antecedents and consequences by (1) the provision of food to patients and (2) the provision of financial rewards for weight loss was hypothesized to improve treatment outcomes. 202 men and women were randomly assigned to no treatment, standard behavioral treatment (SBT), SBT plus food provision, SBT plus incentives, or SBT plus food provision and incentives. The major finding was that food provision significantly enhanced weight loss. Weight losses with SBT averaged 7.7, 4.5, and 4.1 kg at 6, 12, and 18 mo, respectively, compared with 10.1, 9.1, and 6.4 kg, respectively, at the same intervals with the addition of food. Food provision also enhanced attendance, completion of food records, quality of diet, and nutrition knowledge. The authors conclude that the provision of food to weight-loss patients is a promising methodology that deserves further exploration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In suction feeding, a volume of water is drawn into the mouth of a predator. Previous studies of suction feeding in fishes have shown that significant fluid velocities are confined to a region within one mouth width from the mouth. Therefore, the predator must be relatively close to the prey to ensure capture success. Here, theoretical modelling is combined with empirical data to unravel the mechanism behind feeding on a substrate. First, we approached the problem theoretically by combining the stream functions of two sinks. Computational fluid dynamics modelling is then applied to make quantitative predictions regarding the effects of substrate proximity on the feeding hydrodynamics of a benthic shark. An oblique circular cylinder and a shark head model were used. To test the models, we used digital particle image velocimetry to record fluid flow around the mouth of white-spotted bamboo sharks, Chiloscyllium plagiosum, during suction feeding on the substrate and in the water column. Empirical results confirmed the modelling predictions: the length of the flow field can be doubled due to passive substrate effects during prey capture. Feeding near a substrate extends the distance over which suction is effective and a predator strike can be effective further from the prey.  相似文献   
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Four relatively independent emotion-regulation constructs (suppression of negative affect, restraint, repression, and emotional self-efficacy) were tested as outcomes in a randomized trial of supportive-expressive group therapy for women with metastatic breast cancer. Results indicate that report of suppression of negative affect decreased and restraint of aggressive, inconsiderate, impulsive, and irresponsible behavior increased in the treatment group as compared with controls over 1 year in the group. Groups did not differ over time on repression or emotional self-efficacy. This study provides evidence that emotion-focused therapy can help women with advanced breast cancer to become more expressive without becoming more hostile. Even though these aspects of emotion-regulation appear trait-like within the control group, significant change was observed with treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Investigated ordered and equivalence relations among hierarchically arranged fraction identification tasks to determine whether hierarchical ordering among fraction identification problems reflected the replacement of simple rules by complex rules. 456 middle-class 2nd, 3rd, and 4th graders were asked to identify fractional parts of sets of objects. Latent class techniques revealed that Ss applied rules that were adequate for simple problems but had to be replaced to solve more complex problems. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study examined seat belt usage in North Carolina by drivers of 4,151 late model cars equipped with a variety of restraint system types. We measured usage by restraint type (automatic belt, air bag, manual belt), by make/model and by driver characteristics (age, sex, and race). Usage ranged from a high of 94.2% for motorized shoulder belts (but with only 28.6% lap belt usage in these cars) to 73.9% usage of manual lap/shoulder belts in cars equipped with air bags. Various types of misuse of the shoulder belt (e.g. excessive slack, detachment from the door, placement under the arm) were observed in nearly 6% of the sample.  相似文献   
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