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141.
Previous research has found evidence of academic benefits to longer school years. This paper investigates one of the many potential costs of increased school year length, documenting a dramatic decrease in youth suicide in months when school is not in session. A detailed analysis does not find that other potential explanations such as economic conditions, weather or seasonal affective disorder patterns can explain the decrease. This evidence suggests that youth may face increased stress and decreased mental health when school is in session.  相似文献   
142.
On belief-desire reasoning tasks, children first pass tasks involving true belief before those involving false belief, and tasks involving positive desire before those involving negative desire. The current study examined belief-desire reasoning in participants old enough to pass all such tasks. Eighty-three 6- to 11-year-olds and 20 adult participants completed simple, computer-based tests of belief-desire reasoning, which recorded response times as well as error rates. Both measures suggested that, like young children, older children and adults find it more difficult to reason about false belief and negative desires than true beliefs and positive desires. It is argued that this developmental continuity is most consistent with either executive competence or executive performance accounts of the development of belief-desire reasoning.  相似文献   
143.
OBJECTIVES: To identify pediatric residents' understanding and interpretation of reasonable suspicion, in the context of mandated reporting of suspected child abuse. METHOD: A survey was administered to pediatrics and combined medicine/pediatrics residents. An open-ended question plus three operational frameworks for interpreting likelihood examined how residents conceived of reasonable suspicion. Responses were examined for evidence of a group standard, and also compared for internal consistency. RESULTS: Forty-two of 49 residents completed the survey (86% response rate). There were no significant differences in responses based on age, gender, year of residency, or anticipated practice type. Respondents exhibited wide variation in the thresholds they set for reasonable suspicion. On a Differential Diagnosis scale, 10% indicated that "abuse" would have to rank 1st or 2nd; 45% set the threshold at 3rd or 4th; while 45% stated that abuse could be as low as 5th to 10th and still qualify as reasonable suspicion. Using a Estimated Probability scale, 9.5% indicated that "abuse" would need to be >75% likely before reasonable suspicion existed; 28.5% stated that a 60-70% likelihood was needed; 38% identified the necessary likelihood as 40-50%; and 24% set the threshold as low as 10-35%. In comparing individual resident responses for the two scales, 83.3% were internally inconsistent. CONCLUSION: There was no consensus among pediatric residents with regard to (1) a standard meaning for reasonable suspicion, (2) a standard application of reasonable suspicion, or (3) how likely "abuse" must be before reasonable suspicion can be said to exist. Additionally, many residents' conceptions of reasonable suspicion were internally inconsistent.  相似文献   
144.
Martel A  Cross B 《Biomicrofluidics》2012,6(1):12813-128137
Artificial membranes, as a controllable environment, are an essential tool to study membrane proteins. Electrophysiology provides information about the ion transport mechanism across a membrane at the single-protein level. Unfortunately, high-throughput studies and screening are not accessible to electrophysiology because it is a set of not automated and technically delicate methods. Therefore, it is necessary to automate and parallelize electrophysiology measurement in artificial membranes. Here, we present a first step toward this goal: the fabrication and characterization of a microfluidic device integrating electrophysiology measurements and the handling of an artificial membrane which includes its formation, its displacement and the separation of its leaflets using electrowetting actuation of sub-μL droplets. To validate this device, we recorded the insertion of a model porin, α-hemolysin.  相似文献   
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This study aimed to determine if the Garmin Vector (Schaffhausen, Switzerland) power meter produced acceptable measures when compared with the Schoberer Rad Messetechnik (SRM; Julich, Germany) power meter across a range of high-intensity efforts. Twenty-one well-trained cyclists completed power profiles (seven maximal mean efforts between 5 and 600 s) using Vector and SRM power meters. Data were compared using assessments of heteroscedasticity, t tests, linear regression, and typical error of estimate (TEE). The data were heteroscedastic, whereby the Vector pedals increasingly overestimated values at higher power outputs; however, t tests did not identify any significant differences between power meters (> .05). Using linear regression, Vector data were fit to an SRM equivalent (slope = .99; intercept = ?9.87) and TEE produced by this equation was 3.3% (3.0%–3.8%). While the data shows slight heteroscedasticity due to differing strain-gauge placement and resultant torque measurement variance, the Vector appears acceptable for measures of power output across various cycling efforts.  相似文献   
149.
Students with disabilities often take tests under different conditions than their peers do. Testing accommodations, which involve changes to test administration that maintain test content, include extending time limits, presenting written text through auditory means, and taking a test in a private room with fewer distractions. For some students with disabilities, accommodations such as these are necessary for fair assessment; without accommodations, invalid interpretations would be made on the basis of these students’ scores. However, when misapplied, accommodations can also diminish fairness, introduce new sources of construct-irrelevant variance, and also lead to invalid interpretation of test scores. This module provides a psychometric framework for thinking about accommodations, and then explicates an accommodations decision-making framework that includes a variety of considerations. Problems with current accommodations practices are discussed, along with potential solutions and future directions. The module is accompanied by exercises allowing participants to apply their understanding.  相似文献   
150.
This study tested implications of new genetic discoveries for understanding the association between parental investment and children’s educational attainment. A novel design matched genetic data from 860 British mothers and their children with home-visit measures of parenting: the E-Risk Study. Three findings emerged. First, both mothers’ and children’s education-associated genetics, summarized in a genome-wide polygenic score, were associated with parenting—a gene–environment correlation. Second, accounting for genetic influences slightly reduced associations between parenting and children’s attainment—indicating some genetic confounding. Third, mothers’ genetics were associated with children’s attainment over and above children's own genetics, via cognitively stimulating parenting—an environmentally mediated effect. Findings imply that, when interpreting parents’ effects on children, environmentalists must consider genetic transmission, but geneticists must also consider environmental transmission.  相似文献   
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