Local knowledge and comparative scientific traditions

This article argues that all knowledge is inherently local and that localness provides the basis for comparison between indigenous scientific traditions or knowledge production systems. As collective bodies of knowledge, many of the significant differences between knowledge production systems lie in the work involved in creating assemblages from differing practices. Much of the work can be seen in the social strategies and technical devices employed in creating equivalences and connections whereby otherwise heterogeneous and isolated knowledges are enabled to move in space and time from the local site and moment of their production and application to other places and times. In this way contemporary technosciences are compared with the knowledge systems of the medieval mastermasons, the Anasazi, the Inca, the Australian Aborigines and the Pacific navigators.     

Double agency and the ethics of rationing health care: a response to Marcia Angell

The arguments against doctors as "double agents" that are presented by Marcia Angell in the preceding article do not defeat the core justification for rationing some relatively high-expense, low-benefit care, and they do not enable us to conclude that clinicians should be barred from any active, substantive role in decisions to limit that care. They do, however, reveal several important conditions that need to govern cost-conscious medial practice in order to preserve an ethic of fidelity to patients: insurers' profits and providers' incomes must be fair, providers must inform patients of any economic reasons that lead to the foregoing of care, and "direct incentive" arrangements must not be used to contain costs.     

Child and adolescent services research at the national institute of mental health: Research opportunities in an emerging field

This article describes an important new area of research on services for children and adolescents with mental disorders at the National Institute of Mental Health, the parameters of mental health services research for youth, and the opportunities that are available for grant-funded investigations in this area.     

Nonsuicidal physically self-damaging acts in adolescents

To determine the frequency and correlates of nonsuicidal physically self-damaging acts in 12–14 year olds, a two stage epidemiologic survey with a self-administered questionnaire (N=3283) followed by a psychiatric interview of a subsample of the adolescents and their parents (N=444) was used. Prevalence estimates of interview validated nonsuicidal physically self-damaging acts were 2.46% in males and 2.79% in females. Significant relationships were found between nonsuicidal physically self-damaging acts and suicidal ideation, major depression and undesirable life events. Data suggest that physically self-damaging acts occur at substantial rates during early adolescence. The strong correlation between nonsuicidal self-destructive acts and both suicidal ideation and major depression clarifies prior conflicting reports in the literature and suggests that a history of self-damaging acts should be taken into consideration when evaluating for possible depression and suicide risk.     

The effects of exposure to different sources of sexual information on sexual behavior: Comparing a “sex-expert system” to other educational material

Sexpert, an expert computer program designed to counsel couples on their sexual relationships, was evaluated. Eighty-one heterosexual couples were assigned to one of three experimental manipulations (Sexpert, video, and self-help book) or a control condition. Daily sexual behavior monitoring forms and structured retrospective reports served as measures of baseline and post-manipulation behavior. Daily monitoring of sexual behavior failed to show significant changes occurring after the manipulations. However, retrospective data concerning the postmanipulation period show that compared with the control, the Sexpert, video, and book manipulations had a significant positive impact on couples’ sexual behavior, communication, and learning about sexuality. Sexpert, video, and book were similarly evaluated, except that Sexpert was evaluated as more engaging. In addition, subjects retrospectively reported positive changes in communication, relationship satisfaction, and sexual behavior during the baseline period. This suggests that daily behavioral monitoring is intrusive and may confound the variables measured by it.     

Clarifying the task

Those who would enquire into therelationship between “health conceptions” and “health care consequences” are faced with a formidable task. In order to make this challenge manageable it is necessary to define the scope of the task as precisely as possible. Are we, for instance, faced with a purely theoretical challenge; a task for applied philosophy, or must we employ multi-disciplinary methods? This paper argues that while philosophy has a central clarifying role, inquiry into the relationship between “health conceptions” and “health care organisation” can be done properly only through the combined efforts of several disciplines. Unless we are to be concerned only with abstract models it is essential to take account of the reality of health care situations. Given this it is suggested that the study of “health conceptions” is only a part of a greater task (unless all conceptions are to count as “health conceptions”). What is needed is understanding of the possible and actual purposes of health care, and detailed study of their practical implications.     

Calibration of a color monitor for visual psychophysics

It has become common for stimuli used in visual psychophysical experiments to be presented on high-resolution color cathode-ray tubes (CRTs) such as the Barco CDCT 6551. These enable a flexibility of color, spatial-frequency content, temporal-frequency content, duration, size, and position that is not provided by most other media. CRTs are, however, not perfect; they suffer from the effects of temporal instability, spatial variability, lack of phosphor constancy, gun interdependence, and gun nonlinearity. This paper describes methods of assessing these aspects of monitor performance with respect to how significant each may be in psychometric terms. Although every application of CRT use in visual psychophysics is different, some general rules can be formulated to help ensure that unwanted effects are kept to a minimum. For the CRT used in this study (Barco CDCT 6551), a warm-up time of 30-45 min is necessary before chromatic and luminous stability ensues. Restriction of individual gun outputs to within 10%-90% of the possible range ensures that the effects of gun interdependence and lack of phosphor constancy are negligible. Calibration methods dealing with the linearization of gun output are also discussed.     

比较研究-影响中美儿童计算能力差异的认知因素

本研究要确定中美儿童基本计算技能的差异是否与他们使用的解题策略和基本加工过程的速度有关。为此,对中美两国的一年级儿童进行了书面计算能力测验,以及一组计算机呈现的加法作业。中国儿童在计算能力测验上表现出3:1的操作优势。中美儿童使用的解题策略种类一样,但是,中国儿童在策略综合运用的发展程度上超过美国儿童,检索策略的加工速度也超过美国儿童。显然,策略运用和加工速度的差异促成了中国儿童在计算能力测验上的优势.     

Potentiation of the pressor response to stress by tolbutamide in dogs

Tolbutamide has previously been shown to amplify the pressor effects of “exogenous” catecholamines in conscious dogs, possibly due to sensitization of the α₁-adrenoreceptor-mediated vasoconstriction. The objective of this study was to examine if tolbutamide also amplifies the pressor effects of “endogenous” catecholamines released during psychological stress (classical Pavlovian aversive conditioning). Experiments were conducted in β-adrenoreceptor-blocked (propranolol, 1 mg/kg, i.v.) conscious dogs (n=4) trained in classical aversive conditioning. Conditioning was accomplished by following a tone (CS+) with a 1/2 second shock; another tone (CS-) was not followed by any shock and served as control. With saline pretreatment, aversive conditioning (i.e., CS+) increased mean arterial pressure (MAP) only by approximately 4.7% when compared to CS-, whereas with tolbutamide (45 mg/kg, i.v.) pretreatment, the increase in MAP induced by CS+ beyond what was induced by the CS- (approximately 6.2%) was significantly (p<0.05) larger than that with saline pretreatment. In isolated canine femoral arterial segments (n=4), the vasoconstrictor effect of phenylephrine (an α₁-agonist) at 5×10^?6M (which was the EC₅₀ value) was amplified by 2×10^?2M of tolbutamide from 54.0±2.0% to 66.9±2.1%. In conclusion, tolbutamide amplifies the pressor effects of “endogenous” catecholamines in conscious dogs, possibly by sensitization of the α₁-adrenoreceptor-mediated vasoconstriction. This mechanism of action is novel and has not been reported with other agents.     

Distractor clustering enhances detection speed and accuracy during selective listening

The effects of distractor clustering on target detection were examined in two experiments in which subjects attended to binaural tone bursts of one frequency while ignoring distracting tones of two competing frequencies. The subjects pressed a button in response to occasional target tones of longer duration (Experiment 1) or increased loudness (Experiment 2). In evenly spaced conditions, attended and distractor frequencies differed by 6 and 12 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1048-Hz distractors). In clustered conditions, distractor frequencies were grouped; attended tones differed from the distractors by 6 and 7 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1400-Hz distractors). The tones were presented in randomized sequences at fixed or random stimulus onset asynchronies (SOAs). In both experiments, clustering of the unattended frequencies improved the detectability of targets and speeded target reaction times, Similar effects were found at fixed and variable SO As. Results from the analysis of stimulus sequence suggest that clustering improved performance primarily by reducing the interference caused by distractors that immediately preceded the target.