The role of injection cues in the production of the morphine preexposure effect in taste aversion learning

The attenuation of an LiCl-induced conditioned taste aversion (CTA) by LiCl preexposure is mediated primarily by associative blocking via injection-related cues. Given that preexposure to morphine attenuates morphine-induced CTAs, it was of interest to determine whether injection cues also mediate this effect. Certain morphine-induced behaviors such as analgesic tolerance are controlled associatively, via injection-related cues. Accordingly, animals in the present experiments were preexposed to morphine (or vehicle) every other day for five total exposures, followed by an extinction phase, in which the subjects were given saline injections (or no treatment) for 8 (Experiment 1) or 16 (Experiment 2) consecutive days. All of the animals then received five CTA trials with morphine (or vehicle). The morphine-preexposed animals in Experiment 1 displayed an attenuation of the morphine CTA that was unaffected by extinction saline injections, suggesting that blocking by injection cues during morphine preexposure does not mediate this effect. All of the morphine-preexposed subjects in Experiment 2 displayed a weakened preexposure effect, an effect inconsistent with a selective extinction of drug-associated stimuli. The attenuating effects of morphine preexposure in aversion learning are most likely controlled by nonassociative mechanisms, like drug tolerance.     

足球运动员股四头肌肌粗值的测定

膝关节受伤以后,最早出现萎缩的肌肉是股四头肌内侧头。足球运动员膝关节伤病多,所以对其股四头肌肌粗值进行定量分析,具有实际意义。以体表形态数据建立数学模型,推导出股四头肌肌粗值,建立了统一的对比衡量标准。肌粗值的变化,首先是受髌骨上５ｃｍ 外缘腿围影响,其次是受髌中围的影响,相关程度分别为高度相关和低度相关,而肌粗值与髌骨上１０ｃｍ 外缘腿围间变化呈不相关。     

The impact of collective efficacy beliefs on effort and persistence in a group task

Collective efficacy is an important determinant of the motivation of individuals within groups, with increases in collective efficacy producing more effort in a task and greater persistence when faced with failure. To test hypotheses concerning the impact of collective efficacy on effort and persistence, participants (n = 22) were assigned to triads (consisting of the participant and two confederates) and performed three time trials on cycle ergometers. After trial 1, the participants were assigned to either a high or low collective efficacy condition, receiving appropriate bogus performance feedback. All groups received failure feedback after trial 2. Effort was assessed by performance time and maximum heart rate (HRmax) achieved during performance. A 2 (collective efficacy condition) x 3 (trials) analysis of variance with repeated measures on trials revealed significant interaction effects for both performance time and HRmax. Fisher's least significant difference post-hoc tests indicated that, following efficacy manipulation, groups low in collective efficacy significantly reduced both their performance time and HRmax, whereas groups high in collective efficacy maintained performance and HRmax. However, predictions concerning the impact of failure on persistence were not supported. Our results provide partial support for the role of collective efficacy in team sports.     

Playing the ‘Race’ card? Black and minority ethnic students' experiences of physical education teacher education

This paper reports on a study that explored black and minority ethnic (BME) students' experiences of physical education teacher education (PETE) in England. Widening the ethnic diversity of those choosing to enter the teaching profession has been a key policy objective of the Training and Development Agency—the government agency responsible for teacher education—for some years. However PETE programmes, designed to produce specialist physical education (PE) teachers to work with secondary age (11–18 years) pupils, reveal significant and enduring levels of under-representation of BME candidates, compared to other subject specialisms. The study reported here used semi-structured interviews and questionnaires with 25 BME participants from five universities involved in PETE in England. The findings show that BME PETE students share many of the characteristics with their White counterparts, being young, sporty and with a desire to improve PE experiences for future generations. However, in other ways, their experiences reveal the significance of ‘race’ ethnicity, and religion and how these are interwoven with gender to position them as ‘other’ in PETE spaces and within schools. Skin colour and religious dress were significant to stereotyping and everyday interactions that served to position them as ‘out of place’, particularly evident in practical activity sessions and on teaching placements. ‘Race’ and ethnicity as part of their professional education was at best a marginalised discourse, at worse, reproduced a deficit perspective of BME pupils’ and their schooling. The paper concludes by arguing for a critical analysis of the construction of Whiteness through PETE.     

Education and Training Packages for CAD/CAM

The provision of education and training almost always lags behind the needs of industry. This is particularly so in the case of rapidly developing high technology fields such as CAD/CAM (Computer Aided Design and Manufacture), where the educational sector finds it difficult to keep up with industry's requirements not only because of the rapid growth rate, but also because of the high level of funding which is required to purchase and maintain suitable facilities. Two education/training initiatives are described in this paper. The first of these is a pack of resource material for lecturers teaching CAD/CAM to undergraduate level, and the second is a training course for the managers of CAD/CAM systems which is part of the U.K. Manpower Services Commission's Open Tech programme.     

Reliability and concurrent validity of a measure of critical thinking skills in biology

The present study investigated the utility of 52 items, selected from a readily available item pool developed for instructional purposes, when the items are used to measure critical thinking abilities of biology students. The items yield scores that have reasonable internal consistency reliability. Furthermore, analyses involving ACT, Watson-Glaser Critical Thinking Appraisal, and Group Embedded Figures Test scores also suggest that the critical thinking test items have good concurrent validity. Thus, the measure may be useful in both science instruction and future research regarding critical thinking phenomena.     

On orthogonal polynomials

A study is made of the orthogonal polynomials on certain curves in the complex plane. Necessary and sufficient conditions for a set of polynomials to be orthogonal on the curves are obtained in terms of symmetric matrices. The relations of the symmetric matrices to Toeplitz matrices and innerwise matrices are shown.     

The effect of ball carrying method on sprint speed in rugby union football players

Different methods of ball carrying can be used when a player runs with the ball in rugby union. We examined how three methods of ball carrying influenced sprinting speed: using both hands, under the left arm and under the right arm. These methods were compared with running without the ball. Our aim was to determine which method of ball carrying optimizes sprinting speed. Altogether, 48 rugby union players (age 21 +/- 2 years, height 1.83 +/- 0.1 m, body mass 85.3 +/- 12 kg, body fat 14 +/- 5%; mean +/- s) were recruited. The players performed twelve 30-m sprints in total (each player performed three trials under each of three methods of carrying the ball and sprinting without the ball). The design of the study was a form of Latin rectangle, balanced across the trial order for each of the methods and for pairwise combinations of the methods in blocks of four per trial. Each sprint consisted of a 10-m rolling start, followed by a 20-m timed section using electronic timing gates. Compared with sprinting 20 m without the ball (2.58 +/- 0.16 s), using both hands (2.62 +/- 0.16 s) led to a significantly slower time (P < 0.05). Sprinting 20 m with the ball under the left arm (2.61 +/- 0.15 s) or under the right arm (2.60 +/- 0.17 s) was significantly quicker than when using 'both hands' (P < 0.05), and both these methods were significantly slower than when running without the ball (P < 0.05). Accordingly, running with the ball in both hands led to the greatest decrement in sprinting performance, although carrying the ball under one arm also reduced the players' sprinting ability. Our results indicate that to gain a speed advantage players should carry the ball under one arm.