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901.
902.
903.
This study employs a simple enrollment demand model to investigate the regional market environment of a private, church-related, comprehensive institution of higher education offering undergraduate, graduate and professional education. The focus is on price and cross-price elasticities of demand as measures of the competitive threat posed by prominent public and private educational alternatives within the region. We find a significant competitive threat coming from the private sector within the region. This competition raises the net price elasticity of demand for education at this institution to well above unity. We conclude that tuition price subsidies play a critical role in managing enrollment demand at this institution. [JEL J3, J24, J41] 相似文献
904.
Don F. Westerheijden 《Higher Education》1999,38(2):233-254
The author reviews developments in publications on quality assurance of education in (European) higher education over the last decade. The metaphor of sub-atomic structure is used to order the literature in types ('shells') of similar publications, moving from those closely related with the practice of quality assurance methods to more theoretical publications. Some seminal publications are highlighted as 'quantum jumps'. The article ends by noting some recent trends in quality assurance at the system and institutional levels, as well as mentioning theoretically interesting developments, notably the emergence of neo-institutional approaches. 相似文献
905.
906.
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
907.
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
908.
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
909.
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
910.
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