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991.
992.
This paper analyzes recent work in psychology on the nature of the representation of complex forms of knowledge with the goal of understanding how theories are represented. The analysis suggests that, as a psychological form of representation, theories are mental structures that include theoretical entities (usually nonobservable), relationships among the theoretical entities, and relationships of the theoretical entities to the phenomena of some domain. A theory explains the phenomena in its domain by providing a conceptual framework for the phenomena that leads to a feeling of understanding in the reader/hearer. The explanatory conceptual framework goes beyond the original phenomena, integrates diverse aspects of the world, and shows how the original phenomena follow from the framework. This analysis is used to argue that mental models are the subclass of theories that use causal/mechanical explanatory frameworks. In addition, an argument is made for a new psychologism in the philosophy of science, in which the mental representation of scientific theories must be taken into account. 相似文献
993.
Patrick T. Davies Jesse L. Coe Rochelle F. Hentges Melissa L. Sturge-Apple Michael T. Ripple 《Child development》2020,91(2):508-526
This study examined temperament dimensions of emotion as precursors of children's social information processing (SIP) of stressful peer events. Two hundred and forty-three preschool children (M = 4.60 years) and their primary caregivers participated in two measurement occasions spaced 2 years apart. Observations of temperamental anger, fearful distress, positive affect, and effortful control were assessed in multiple laboratory tasks across two visits at Wave 1. SIP assessments from vignettes of peer challenges were repeated across two waves and included: eye tracking measures of attention to peer emotion displays, hostile attribution bias, hostile solutions, and subjective distress. Findings from structural equation models with inclusion of autoregressive controls indicated that effortful control, fear, and anger predicted subsequent changes in specific SIP dimensions. 相似文献
994.
Testing programs are often interested in using a student growth measure. This article presents analytic derivations of the accuracy of common student growth measures on both the raw scale of the test and the percentile rank scale in terms of the proportional reduction in mean squared error and the squared correlation between the estimator and target. The study contrasts the accuracy of the growth measures against that of current status measures—current test scores and their percentile ranks. Key findings include the extent that status measures are more accurate than any of the growth measures and that alternative methods to estimate growth could be more accurate than the currently used methods. Our findings highlight the importance for evaluating the statistical properties of growth measures along with other concerns for states that are debating the reporting of growth. Our results also point out that assessing the accuracy of growth measures requires the specification of quantities of interest in terms of latent achievement rather than observed test scores, which is common practice for developing status measures but essentially never done by testing programs for growth measures. 相似文献
995.
Dielectrophoretic properties of DNA have been determined by measuring capacitance changes between planar microelectrodes. DNA sizes ranged from 100 bp to 48 kbp, DNA concentrations from below 0.1 to 70 μg∕ml. Dielectrophoretic spectra exhibited maximum response around 3 kHz and 3 MHz. The strongest response was found for very long DNA (above 10 kbp) and for short 100 bp fragments, which corresponds to the persistence length of DNA. The method allows for an uncomplicated, automatic acquisition of the dielectrophoretic properties of submicroscopical objects without the need for labeling protocols or optical accessibility. 相似文献
996.
Although sport management researchers have produced findings with regard to diversity in the leadership positions of college athletics, this examination has focused separately on gender (Inglis et al., 1996, Inglis et al., 2000; Inglis, Danylchuk, & Pastore, 2000; Knoppers et al., 1991, National Collegiate Athletic Association, 2009a, Sartore and Cunningham, 2007) or race (Cunningham and Sagas, 2004a, Cunningham and Sagas, 2004b, Cunningham et al., 2001, Cunningham et al., 2006). The current study, framed by intersectionality, identifies barriers contributing to the under-representation of Black women in head coaching jobs in Division I women's basketball in the United States. The assistant coaches cited access discrimination, lack of support, and prevalent stereotypes as barriers. In negotiating these barriers, the women discussed the importance of networking, mentoring and presenting “a proper image” for big-time athletics. To eradicate these barriers, the women recommended expanding job pools; more mentoring by athletic department personnel; and more development programs offered for young Black females. 相似文献
997.
Casikar V Mujica E Mongelli M Aliaga J Lopez N Smith C Bartholomew F 《Indian journal of clinical biochemistry : IJCB》2010,25(3):311-314
Andean Indians have used coca leaves (Erythroxylon coca and related species) for centuries to enhance physical performance. The benefits and disadvantages of using coca leaf have
been a subject of many political debates. The aim of this study was to investigate the effects of chewing coca leaves on biochemical
and physiological parameters. Cutaneous microdialysis catheters were used to estimate systemic biochemical changes. We subjected
10 healthy adult males (local residents) in Cajamarca (Peru, altitude 2700 m) to a standardised exercise routine on a stationary
cycle ergometer. The blood pressure, oxygen saturation (digital), pulse, VO2 max and ECG (Holter monitor) were recorded before
the exercise. Cutaneous microdialysis catheters were introduced in the forearm. The subjects were given to chew 8 g of coca
leaves with a small amount of lime. They were then placed on the cycle ergometer for 20 min. Blood pressure, oxygen saturation,
pulse, ECG and VO2 max were recorded. Pyruvate, glucose, lactate, glycerol and glutamate levels were estimated. Oxygen saturation,
blood pressure, and pulse rate did not show any significant changes between the two groups. Glucose levels showed hyperglycaemic
response. Glycerol, Lactate and Pyruvate increased. Glutamate remained unchanged. Similar changes were not seen in the controls.
These results suggest that coca leaves have blocked the glycolytic pathway of glucose oxidation resulting in accumulation
of glucose and pyruvate. The energy requirement for exercise is being met with beta-oxidation of fatty acids. The glycerol
released was also getting accumulated since its pathway for oxidation was blocked. These experimental findings suggest that
chewing coca leaves is beneficial during exercise and that the effects are felt over a prolonged period of sustained physical
activity. 相似文献
998.
Time-in and time-out were used to treat inappropriate and noncompliant behaviors in a child with severe language disabilities and a child with a moderate mental disability and cerebral palsy. The target behaviors for Jeremy were compliance with first-time presented teacher instructions, elopement and aggression. Prior to intervention, archival baseline data for Jeremy suggested a compliance rate with teacher directives of approximately 9% and a high frequency of elopement and aggression. Following implementation of a compliance training package, compliance to teacher directives increased to 97% within the first week of intervention and minimal instances of elopement and aggression. Two, 24, and 40-week follow-up compliance checks yielded mean rates of 98%, 99%, and 98% respectively and no elopement or aggression. Reduction in object tossing behaviors was targeted for Jenny. Archival baseline, indicated through parent report, suggested tossing rates of 80% of the times objects were in hand. Frequency of object tossing behavior decreased to a near-zero level during intervention. The use of this intervention package with children in an effort to deter future chronic noncompliance and inappropriate behavior is discussed. © 1997 John Wiley & Sons, Inc. 相似文献
999.
1000.