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191.
192.
Abstract

Real-world experiments that test new technologies can affect policy and practice by introducing new objects of intervention through tinkering; the ad hoc work of realigning relations in the face of frictions, surprises, and disturbances that occur when introducing a technology. In a pilot study on aggression detection, tinkering moved aggression in and out of the human body. In the end, the pilot defined aggression as a set of acoustic-physical variables representing the aroused human body, alongside other signals of aggression. How aggression as an object intervention was shaped by tinkering is relevant because it involved inclusions and exclusions by the authorities who identified aggression, the methods they applied, and mandate for intervention. A focus on relations that are tinkered within a real-world experiment permits critical engagement with this format. Although the real-world experimental format is credited with producing knowledge about a technology's ‘actual’ performance, actors and events at the pilot study location were made only selectively relevant. Analyses of real-world experiments should therefore explain how experiments selectively make the world relevant, giving only particular objects of intervention a truth status.  相似文献   
193.
血红素氧合酶-1(HO-1)是血红素分解的起始酶和限速酶,它分解血红素最终生成胆红素、一氧化碳和铁.这三种产物通过抗炎症损伤、抗氧化应激、抗细胞增殖、抗细胞凋亡、抑制血小板聚集、调节血管张力及细胞内信号传递等途径对心血管系统起着重要的保护作用.研究显示,HO的诱导剂及多种能降低心血管病风险的药物能诱导 HO-1表达增加,从而起到抗动脉粥样硬化的发生发展及调节血压的作用.因此开发临床可应用的HO诱导剂,甚至开发HO的基因治疗方法是目前研究的方向.  相似文献   
194.
探讨早期目标血糖管理对严重脓毒症患者HMGB1变化的影响.严重脓毒症患者随机分为血糖控制A(4.4mmol/L~6.1mmol/L)、B(6.2mmol/L~8.3mmol/L)、C(8.4mmol/L~10.0mmol/L)三组.给予早期目标血糖管理,入ICU后0d、1d、3d、5d、7d采血测TNF-α、HMGB1浓度.三组TNF-α、HMGB1浓度及APACHEⅡ评分均呈下降趋势,A组HMGB1浓度及APACHEⅡ评分在第7d较B、C组明显降低(P<0.05).A组28d病死率较B、C组降低(P>0.05).严重脓毒症患者在早期目标血糖管理下,显著降低HMGB1浓度,降低病死率和改善预后,HMGB1可用来评价脓毒症的严重程度及预后.  相似文献   
195.
This cross‐sectional study investigated the significant differences in students’ self‐efficacy and their involvement in learning science. Nine hundred and twenty‐two elementary school fifth graders, 499 junior high school eighth graders, and 1455 senior or vocational high school eleventh graders completed the students’ questionnaire. Analyses of variance (ANOVAs) and independent t‐tests compared the significant similarities and differences across school levels and genders. The initial findings were as follows: A sharp decline in boys’ and girls’ self‐efficacy scores from elementary to secondary school levels; boys have significantly higher self‐efficacy scores than girls at vocational and senior high school levels; students with more involvement in science learning presented significantly higher self‐efficacy scores than those with less involvement. The significant discrepancies in terms of gender and age in students’ self‐efficacy and involvement in learning science need to be addressed. Implications and limitations are provided.  相似文献   
196.
Are people more prosocial in a religious context? We addressed this question through an experiment. We randomly placed participants in the control group in a neutral location (a lecture hall), and we placed participants in the experimental group in a religious location (a chapel). The participants then took part in a one‐shot three‐person public goods game, which measured participants’ degree of cooperativeness. The results showed that participants in the experimental group cooperated significantly more than did participants in the control group. Furthermore, participants’ beliefs about other participants’ cooperativeness were more positive in the experimental group than they were in the control group. Improved expectations of others partially explained the enhanced cooperation in the religious context. We found no main or interaction effect of self‐reported religiosity in the experiment.  相似文献   
197.
Previous research has found a relationship between individual differences in children’s precision when nonverbally approximating quantities and their school mathematics performance. School mathematics performance emerges from both informal (e.g., counting) and formal (e.g., knowledge of mathematics facts) abilities. It remains unknown whether approximation precision relates to both of these types of mathematics abilities. In the current study, we assessed the precision of numerical approximation in 85 3- to 7-year-old children four times over a span of 2 years. In addition, at the final time point, we tested children’s informal and formal mathematics abilities using the Test of Early Mathematics Ability (TEMA-3). We found that children’s numerical approximation precision correlated with and predicted their informal, but not formal, mathematics abilities when controlling for age and IQ. These results add to our growing understanding of the relationship between an unlearned nonsymbolic system of quantity representation and the system of mathematics reasoning that children come to master through instruction.  相似文献   
198.
The authors investigated the relation between mental rotation (MR) and computer game-playing experience. Third grade boys (n = 24) and girls (n = 23) completed a 2-dimensional MR test before and after playing computer games (during 11 separate 30-min sessions), which either involved the use of MR skills (the experimental group) or did not involve the use of MR skills (the control group). The experimental group outperformed the control group on the MR posttest but not on the pretest. Boys outperformed girls on the pretest but not on the posttest. Children whose initial MR performance was low improved after playing computer games that entailed MR skills. The findings imply that computer-based instructional activities can be used in schools to enhance children's spatial abilities.  相似文献   
199.
Although it is generally acknowledged that experiences of frustration, confusion, and anxiety are embodied phenomena, very little is known about how these processes modulate presumably unconscious, but constantly present, subtle bodily movement. We addressed this problem by tracking the low-level dynamics of body movement, using 1/f noise, pink noise, or “fractal scaling”, during naturalistic experiences of affect in two studies involving deep learning and effortful problem-solving. Our results indicate that body movement fluctuations of individuals experiencing cognitive equilibrium was characteristic of correlated pink noise, but there was a whitening of the signal when participants experienced states that are diagnostic of cognitive distress such as anxiety, confusion, and frustration. We orient our findings within theories that emphasise the embodied nature of cognition and affect and with perspectives that view affective and cognitive processes as emergent products of a self-organising dynamical system (the brain) that is inextricably coupled to the body.  相似文献   
200.
Eight educationally handicapped boys ranging in age form 10 to 11 years old and described as the worst behavior problems in their class participated in a series of single-subject studies carried out in their self-contained classrooms. Three served as target subjects, using self-reinforcement procedures to increase their sustained on-task behavior in a treatment setting; five served as generalization subjects. Data were collected in three settings within the self-contained classroom; an early morning treatment setting, a late morning generalization setting, and an afternoon generalization setting. The three target subjects averaged a 51% increase over their baseline median levels of sustained on-task behavior in the treatment setting. They averaged 84% and 96% generalization to the late morning and afternoon generalization settings, respectively. These results demonstrate that self-reinforcement can produce setting generalization of treatment effects in the absence of prior externally determined reinforcement. Evidence for subject and subject-setting generalization was also obtained.  相似文献   
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