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51.
The professional and economic challenges to psychologists posed by organized medicine have been stymied in the past by the Federal Trade Commission and by strict enforcement of the antitrust laws. Now that professionals' competition and consumer choice are being supported in the courts, the American Medical Association (AMA) is redoubling its efforts to retain a monopolistic hold on health care, hospital practice, and health insurance throughout the nation. Organized psychology, with the help of other professions and the Congress, has barely held the line against politically and economically stronger forces. The Association for the Advancement of Psychology and the American Psychological Association actively opposed the AMA's proposed legislation in 1981 and 1982 that would have allowed the AMA to circumvent valid law. The medical profession has actively worked to control all health care and deny psychologists hospital staff privileges, preventing group practice between physicians and psychologists, denying them health insurance reimbursement, and restricting psychological services to physician supervision. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
Evaluation of two portable lead-monitoring methods at mining sites   总被引:1,自引:0,他引:1  
Two methods for measuring airborne lead using field-portable instruments have been developed by the National Institute for Occupational Safety and Health (NIOSH): Method 7702 uses X-ray fluorescence (XRF), and Method 7701 employs ultrasonic extraction (UE) followed by anodic stripping voltammetry (ASV). The two portable methods were evaluated at mining sites. Area air samples were collected throughout two mills where ore from nearby mines was processed; the primary constituent of the ore was lead sulfide (galena). The air samples were collected on 37 mm mixed cellulose ester membrane filters housed within plastic filter cassettes. At the end of the work shift, the cassettes were collected and taken to a room off-site for analysis by the two portable methods. The filter samples were first analyzed by XRF and then by UE/ASV. Calibration was verified on both instruments according to standard procedures. The samples were then sent for confirmatory analysis via flame atomic absorption spectrometry (FAAS) according to NIOSH Method 7082. Pairwise comparisons between the methods using the paired t-test showed no statistically significant differences between ASV and FAAS (P>0.05); however, the comparison between XRF and FAAS was statistically significant (P<0.05). The elevated lead concentrations reported by XRF relative to FAAS were likely the result of the ability of XRF to report total lead, including lead silicates. This form of lead is not liberated in the digestion process prior to FAAS analysis, and is therefore not detected by this method. Despite this discrepancy, lead concentrations measured by both portable technologies were found to be highly correlated with the laboratory method (R2>0.96), suggesting that they are suitable as screening methods for airborne lead at mining sites.  相似文献   
53.
Microchip-based purification of DNA from biological samples   总被引:10,自引:0,他引:10  
A microchip solid-phase extraction method for purification of DNA from biological samples, such as blood, is demonstrated. Silica beads were packed into glass microchips and the beads immobilized with sol-gel to provide a stable and reproducible solid phase onto which DNA could be adsorbed. Optimization of the DNA loading conditions established a higher DNA recovery at pH 6.1 than 7.6. This lower pH also allowed for the flow rate to be increased, resulting in a decrease in extraction time from 25 min to less than 15 min. Using this procedure, template genomic DNA from human whole blood was purified on the microchip platform with the only sample preparation being mixing of the blood with load buffer prior to loading on the microchip device. Comparison between the microchip SPE (microchipSPE) procedure and a commercial microcentrifuge method showed comparable amounts of PCR-amplifiable DNA could be isolated from cultures of Salmonella typhimurium. The greatest potential of the microchipSPE device was illustrated by purifying DNA from spores from the vaccine strain of Bacillus anthracis, where eventual integration of SPE, PCR, and separation on a single microdevice could potentially enable complete detection of the infectious agent in less than 30 min.  相似文献   
54.
Autonomy and Common Ground in Human-Robot Interaction: A Field Study   总被引:1,自引:0,他引:1  
The use of robots, especially autonomous mobile robots, to support work is expected to increase over the next few decades. However, little empirical research examines how users form mental models of robots, how they collaborate with them, and what factors contribute to the success or failure of human-robot collaboration. A two-year observational study of a collaborative human-robot system suggests that the factors disrupting the creation of common ground for interactive communication change at different levels of robot autonomy. Our observations of users collaborating with the remote robot showed differences in how the users reached common ground with the robot in terms of an accurate, shared understanding of the robot's context, planning, and actions - a process called grounding. We focus on how the types and levels of robot autonomy affect grounding. We also examine the challenges a highly autonomous system presents to people's ability to maintain a shared mental model of the robot  相似文献   
55.
Investigated in 3 experiments the relationships between affect intensity and basal, evoked, and perceived cardiac arousal. Affect intensity was assessed using R. J. Larsen and E. Diener's (1987) Affect Intensity Measure (AIM). Cardiac arousal was evoked with exercise in the 1st study and with mental arithmetic in the 2nd and 3rd. Perceived cardiac arousal was measured under optimal conditions using a standard heartbeat discrimination procedure. Women as a group scored higher on the AIM. Affect intensity was unrelated to basal or evoked cardiac arousal and was negatively related to perceived cardiac arousal in all 3 studies. Data suggest that affect intensity, although unrelated to actual physiological arousal, is negatively related to the accuracy with which individuals perceive their own arousal. Results are discussed within the context of an expanded arousal-regulation model (J. Blascovich, 1990). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
56.
Reeler (rl/rl) and reeler/wild-type (+/rl) mice synthesize Reln at subnormal rates, as do patients with schizophrenia, bipolar disorder, and autism, thereby forming the basis for a Reln hypothesis for vulnerability to these psychopathologies and justifying attention to the behavioral phenotypes of Reln-deficient mice. Tests of gait, emotionality, social aggression, spatial working memory, novel-object detection, fear conditioning, and sensorimotor reflex modulation revealed the behavioral phenotype of rl/rl, but not +/rl, mice to be different from that of wild-type (+/+) mice. These results reveal no effect of Reln gene dosage and provide significant challenges to both the Reln and the neurodevelopmental hypotheses of the etiology of major psychopathologies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
Two experiments tested the hypothesis that the hypnotic underestimation of time is mediated by attentional processing. In Exp 1, variations in the demands placed on attentional resources produced substantial differences in the subjective estimates of identical length intervals occurring within a hypnotic context. ln Exp 2, attentional manipulation was assessed in both hypnotic and waking contexts. Time judgments were again found to vary with attentional demands but not with hypnotic context. The results are consistent with a busy beaver hypothesis, which holds that hypnotic, as well as nonhypnotic, time estimates are a by-product of the attentional processing demands of the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
Chlorine dioxide has been historically used as a disinfecting agent for drinking water supplies and surfaces. Widespread use as an alternative option for prevention and treatment of COVID-19 has emerged due to a lack of specific treatment. We present the case of a 55-year-old male who developed acute kidney injury and disseminated intravascular coagulation after chlorine dioxide prophylactic ingestion, with regression after therapy with hemodialysis.  相似文献   
59.
Objective: To examine gender differences in the peer relations of children with congenital neurodevelopmental conditions (NDC). Participants: Thirty-four children with cerebral palsy or spina bifida and 41 typically developing (TD) children, ages 6-12. Measures: Personality Inventory for Children-Second Edition (PIC-2), Social Network Inventory for Children-Child Version, and the Friendship Quality Questionnaire-Revised (FQQ-R). Results: Children with NDC report smaller social networks and lower quality of friendships than TD peers. Group × Gender interaction effects were not significant. Conclusion: Prior to adolescence, the social differences and risks associated with NDC do not appear to be gender specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
For adolescents with Type 1 diabetes, lower family income may be associated with poorer diabetes management through depleted parental psychological resources (i.e., higher parental depressive symptoms, lower parental acceptance). Adolescents (N = 252; 46% male) aged 10–14 years with Type 1 diabetes assessed the acceptance of their mother and father (e.g., “gives me the feeling that she likes me as I am”; “she doesn't feel she has to make me over into someone else”). Mothers provided information on family income and demographics. Both mothers and fathers reported their depressive symptoms. HbA1c scores were indexed via medical records. Lower family income was associated with higher (i.e., worse) HbA1c, more mother and father depressive symptoms, and less acceptance from both parents. Mediation analyses revealed that the relationship of lower family income with metabolic control occurred indirectly through lower maternal and paternal acceptance and lower adherence. Lower family income may impair the quality of parent—adolescent relationships that are beneficial for good diabetes management. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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