农户参加新型农村合作医疗项目的影响因素分析

本文以农户参与新型农村合作医疗项目的决策行为为例,探讨农户大病风险处理行为及参加新农合的影响因素.本文分析认为,农户比较购买医疗保险和自我保险的预期效用来决定是否参加"新农合";农户比较正规和非正规医疗保障成本高低实现净收益最大化.农户参与"新农合"的决策受到资源禀赋、疾病风险特征和"新农合"制度环境因素的影响.本文最后提出了相关政策建议.     

Look Again: Pedagogical Demonstration Facilitates Children’s Use of Counterevidence

In learning about the world children must not only make inferences based on minimal evidence, but must deal with conflicting evidence and question those initial inferences when they appear to be wrong. Four experiments (N = 144) found that young children were significantly more likely to revise their initial inferences when conflicting evidence was explicitly demonstrated for them. Four- and five-year-old children saw deterministic evidence about which objects had causal powers, and then saw counterevidence conflicting with that initial pattern. Critically, the conflicting evidence was either demonstrated communicatively and pedagogically, or produced in an intentional but nonpedagogical manner. Only when evidence was explicitly demonstrated for them did children revise their initial hypothesis and use a subtle clue to infer the correct rule.     

Bar velocities capable of optimising the muscle power in strength-power exercises

This study aimed at testing whether there are mean propulsive velocities (MPVs) capable of maximising the mean propulsive power (MPP) during the execution of bench press (BP), bench throw (BT), half squat (HS) and jump squat (JS). Additionally, we assessed the differences in MPP/MPV between ballistic and traditional exercises. Seventeen male rugby sevens players performed MPP tests in BP, BT, HS and JS and maximum isometric force (MIF) tests in HS and BP. The JS presented higher MPP (977.4 ± 156.2 W) than the HS (897.9 ± 157.7 W) (P < 0.05); the BP (743.4 ± 100.1 W) presented higher MPP than the BT (697.8 ± 70.4 W) (P < 0.05). Ballistic exercises presented higher optimum MPV (JS = 1.02 ± 0.07 m·s^?1; BT = 1.67 ± 0.15 m·s^?1) than traditional exercises (HS = 0.93 ± 0.08 m·s^?1; BP = 1.40 ± 0.13 m·s^?1) (P < 0.05). The optimum MPP in the JS, BT, HS and BP occurred at 28.2 ± 5.79, 23.3 ± 4.24, 32.4 ± 9.46 and 27.7 ± 5.33% of the MIF, respectively. The coefficient of variation (CV) of MPV at optimum MPP ranged from 7.4% to 9.7%, while the CV of %MIF ranged from 18.2% to 29.2%. The MPV is a more precise indicator of the optimum loads than the percentages of MIF due to its low inter-subject variability as expressed by CV. Therefore, MPV can be used to determine the optimum power load in the four investigated exercises.     

Kinematic sequence patterns in the overhead baseball pitch

ABSTRACT

Conceptually, an efficient baseball pitch demonstrates a proximal-to-distal transfer of segmental angular velocity. Such a timing pattern (or kinematic sequence) reduces stress on musculoskeletal structures of the throwing arm and maximises ball velocity. We evaluated the variability of kinematic sequences in 208 baseball pitches. 3D biomechanical pitch analyses were performed on 8–10 fastball pitches from 22 baseball pitchers (5 high school, 11 collegiate and 6 professional). The kinematic sequence patterns – time of peak angular velocity of five body segments: pelvis, trunk, arm, forearm and hand – were measured. None of the pitches analysed demonstrated an entirely proximal-to-distal kinematic sequence. Fourteen different kinematic sequence patterns were demonstrated, with the most prevalent sequence being pelvis → trunk → arm → hand → forearm. Fewer than 10% of the pitchers performed only one kinematic sequence pattern across the sampled pitches. The variability of the kinematic sequence was similar in high-school pitchers and professionals. Previous studies report that deviation from the proximal-to-distal kinematic sequence is associated with increased injury risk. As a method of evaluating the efficient transfer of energy to the hand, the kinematic sequence may provide insight to injury risk in the future. The ideal kinematic sequence and ideal variability of the sequence when throwing have yet to be determined.     

Developing the reflective practitioner: placement and the ways of knowing of business and accounting undergraduates

This study aims to identify how students' epistemological beliefs or ways of knowing (comprising cognitive, intrapersonal and interpersonal aspects) develop during work-based placement. Data comprise 32 semi-structured interviews with 17 business and accounting students at a UK university. Findings show that the taking of responsibility is the key stimulus for development: intrapersonally through a changing sense of self and interpersonally though changing relationships with others. A lack of cognitive development appears to arise from a student focus on how they participate within the workplace, rather than on their workplace practice. These findings support the need for a connective view of the curriculum: strengthening connections between formal (university) learning and informal (placement) learning, and between ‘vertical’ and ‘horizontal’ development. In particular, there should be an emphasis on the student's ability to identify relationships between work experience, the knowledge and skills that underpin practice, as well as the context of participation.     

Preschoolers use intentional and pedagogical cues to guide inductive inferences and exploration

Children are judicious social learners. They may be particularly sensitive to communicative actions done pedagogically for their benefit, as such actions may mark important, generalizable information. Three experiments (N = 224) found striking differences in preschoolers’ inductive generalization and exploration of a novel functional property, depending on whether identical evidence for the property was produced accidentally, intentionally, or pedagogically and communicatively. Results also revealed that although 4‐year‐olds reserved strong generalizations for a property that is pedagogically demonstrated, 3‐year‐olds made such inferences when it was produced either intentionally or pedagogically. These findings suggest that by age 4 children assess whether evidence is produced for their benefit in gauging generalizability, giving them a powerful tool for acquiring important kind‐relevant, generic knowledge.     

The Modern Olympic Games: Fanfare and Philosophy, 1896–1972

Women attained leadership roles within the American Physical Education Association much earlier than in organizations like the American Medical Association and the American Physiological Society. Women also were members of the American Academy of Physical Education before its official founding in 1930. Archival records and responses by current members suggest that, for most part, they believe that their experiences have been positive. Since 1941, 18 women have been elected AAKPE president. Between 1951, when the publishing of papers/responses at annual meetings began, and 1979, contributions by women ranged from about 33-44%. Since 1980, the percentage has declined as has the number of women elected to Academy membership. This paper presents a brief history of women within the AAKPE and suggests possible reasons for the recent decline.     

A Prelude to the Rise of Sport: Ante-bellum America, 1850–1860

This paper analyzes the Olympic dilemma from the perspective of social psychology. Specifically, the contact theory is applied to the interaction of organizers, athletes, and spectators at the Olympic Games. The literature investigating the relationship between interaction and the development of positive feelings among participants is reviewed and, where possible, hypotheses based upon the contact theory are developed. Finally, changes are suggested in the Olympic format which would increase the opportunities for positive outcomes from interaction.     

Young Children’s Thinking About Decomposition: Early Modeling Entrees to Complex Ideas in Science

This study was part of a multi-year project on the development of elementary students’ modeling approaches to understanding the life sciences. Twenty-three first grade students conducted a series of coordinated observations and investigations on decomposition, a topic that is rarely addressed in the early grades. The instruction included in-class observations of different types of soil and soil profiling, visits to the school’s compost bin, structured observations of decaying organic matter of various kinds, study of organisms that live in the soil, and models of environmental conditions that affect rates of decomposition. Both before and after instruction, students completed a written performance assessment that asked them to reason about the process of decomposition. Additional information was gathered through one-on-one interviews with six focus students who represented variability of performance across the class. During instruction, researchers collected video of classroom activity, student science journal entries, and charts and illustrations produced by the teacher. After instruction, the first-grade students showed a more nuanced understanding of the composition and variability of soils, the role of visible organisms in decomposition, and environmental factors that influence rates of decomposition. Through a variety of representational devices, including drawings, narrative records, and physical models, students came to regard decomposition as a process, rather than simply as an end state that does not require explanation.