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41.
应WTO反倾销协议的原则和要求,最高人民法院制定了审理反倾销行政案件的规定,尝试建立我国的反倾销司法审查制度。基于反倾销调查程序涉及复杂的经济数据(事实)问题,我国相关的司法审查制度中欠缺对倾销和损害构成的认定与评判司法审查技术层面上的具体规定。我国应借鉴欧共体、美国等国家和地区反倾销审查的司法经验,规范和完善我国反倾销审查程序,以使我国反倾销行政案件的审理程序和实体规定符合WTO反倾销审查的原则和要求。  相似文献   
42.
以1—溴己烷,丙二酸二乙酯和丙烯醛为原料,经五步反应首次合成了溴化[2—(5—己基—1,3—二氧环己烧—2—基)乙基]三乙基铵(h).  相似文献   
43.
The crisis of education frequently is framed in terms of methods, where quantitative research is accused of making the subject invisible through quantification, whereas qualitative research is credited for the emphasis on subjectivity and the discursive construction of reality. Such formulations fail to take into account a long-standing critique that interpretive (constructivist) research, too, makes invisible the real, living subject who is coping with an inherently open life, placing in its stead a ratiocinating individual. In this article, an argument is made for a concrete educational science concerned with the person who is not only (agential) subject but also subject and subjected to the condition it contributes to producing. This subject never is in complete control over its condition, cannot ever know precisely what is currently happening, and at best witnesses rather than grasps or constructs what is going on. This viewpoint requires a rethinking of the subject in/of educational science. Such a project of rethinking the subject involves shifting the minimum units of analysis: from (inter-) action to transaction, from an experience [Erfahrung] to inchoate lived-experiencing [perezhivanie, Erleben], from entities and processes to dramatic events.  相似文献   
44.
Abstract

The primary objective of this study was to examine the relationship between heart rate intensity and pedometer step counts in adolescents. To determine cardiorespiratory fitness, 106 participants (47 boys, 59 girls, mean age 14.2 years, s = 0.8) completed the Queen's College Step Test and were classified as having low, moderate or high cardiorespiratory fitness. Adolescents also completed a 10-min treadmill trial while wearing a pedometer and heart rate monitor. The participants were instructed to maintain their heart rate between 65 and 75% of their maximum heart rate while running or walking on a treadmill. A heart rate of 65–75% maximum was associated with 146 steps per minute (s = 22) in boys and 137 steps per minute (s = 22) in girls. Results of analysis of variance indicated that there was a main effect for level of fitness (F 2,102 = 9.36, P < 0.001). The correlation between mean steps per minute and estimated maximum oxygen consumption was statistically significant (r = 0.44, P < 0.001). The results from this study suggest that a step rate of 130 steps per minute is equal to 65–75% maximum heart rate in low-fit adolescents and achieving 130 steps per minute could be used as an initial goal to improve fitness.  相似文献   
45.
Abstract

Previous investigators have yielded conflicting results in testing the hypothesis that the use of toe clips during bicycle ergometry produces a higher maximal oxygen uptake ([Vdot]O 2 max) than testing without toe clips. Eight men, four competitive cyclists and four competitive distance runners volunteered to participate in three randomized [Vdot]O 2 max tests: 1) a treadmill running lest, 2) a bicycle ergometer test using standard toe clips, and 3) a test on the same ergometer without toe clips. The highest mean [Vdot]O 2 max was observed in the treadmill condition as expected. However, no statistically significant difference in mean [Vdot]O 2 max or performance time was observed between the toe-clip and no toe-clip conditions. Based on these results, the research hypothesis was rejected and no favorable physiological effect may be attributed to the use of toe clips.  相似文献   
46.
Abstract

The effect of caffeine ingestion on submaximal endurance performance of 15 females and 13 males was investigated. After completing a [Vdot]O 2 max test, each subject performed two submaximal cycling tests at approximately 75% of [Vdot]O 2 max to exhaustion. For the caffeine (C) trials, 300 mg of caffeine was added to 250 ml of decaffeinated coffee and ingested one hour prior to the exercise. The decaffeinated (D) trial involved consuming 250 ml of decaffeinated coffee an hour prior to the test. The C and D trials were administered randomly using a standard double blind design. Physiological parameters were monitored each 9, 10, and 11 minute intervals throughout each trial and averaged. As expected the [Vdot]O 2 (L · min ?1 ), [Vdot]E and work outputs (kgm) were significantly (p < 0.001) higher for the males than the females. All other variables, time to exhaustion, [Vdot]O 2 (ml · kg · min ?1 ), R, HR, and rating of perceived exertion (RPE) were not significantly (p > 0.05) different between the sexes for either the C or D trials. Time to exhaustion was 14.4 and 3.1% longer for the C trials for the females and males, respectively, however these increases were not significant (p > 0.05). Furthermore, there were no significant differences (p > 0.05) for any of the measured variables during successive 10 minute work intervals between the C and D trials for either sex. These results do not support the general use of caffeine in moderate amounts as an ergogenic aid for either males or females, but from a practical point it appears that caffeine may have an ergogenic effect on specific individuals.  相似文献   
47.
Abstract

The purpose of this study was to determine the effects of a Nautilus circuit weight training program on muscular strength and maximal oxygen uptake ([Vdot]O 2 max) by comparing these effects to those produced by adhering to either a free weight (FW) strength training program or a running (R) program. Male college students who voluntarily enrolled in either a FW training class (n = 11), a Nautilus (N) circuit weight training class (n= 12), or a R conditioning class (n= 13) were subjects for this investigation. All groups participated in their respective programs 3 days per week for 10 weeks. Strength was assessed using a Cybex II isokinetic dynamometer set at an angular velocity of 60° · s ?1 and a damping of 2. The FW group served as the control group for the assessment of [Vdot]O 2 max changes, while the R group served as controls for the assessment of strength differences. ANCOVA revealed that the N and R groups experienced significant (p < .01) increases in [Vdot]O 2 max expressed in L · min ?1 (10.9 and 11.4%), ml · kg ?1 · min ?1 (10.8 and 11.7%), and ml · kgLBW ?1 · min ?1 (7.1 and 7.5%) when compared to the FW group. There were no significant differences between the N and R groups. There were no significant differences among groups in final peak torque values (after covariance), and torque at the beginning and end of the range of motion for the knee extensors, knee flexors, elbow extensors, and elbow flexors. In general, isokinetic strength values elicited by the N group compared favorably to those generated by the FW group. It was concluded that for a training period of short duration, Nautilus circuit weight training appears to be an equally effective alternative to standard free weight (strength) and aerobic (endurance) training programs for untrained individuals.  相似文献   
48.
Abstract

Previous investigations regarding activity during the post-knowledge of results (KR) interval have considered the performance of interference groups over KR-supplied acquisition trials as indicative of effects upon learning. The absence of transfer tests in these studies, however, preclude such an assumption. Indeed, the use of a retention test in the present investigation (no-KR trials following an interpolated phase) provided evidence suggesting that, while activity during the post-KR interval is detrimental to performance, no such assumption can be made regarding this effect upon learning. These findings are discussed relative to recent arguments that some of the commonly accepted “Laws of KR” may be contradictory when applied simultaneously to motor learning and performance.  相似文献   
49.
Abstract

The aim of this study was to establish the net energy cost of dribbling a soccer ball. Eight male footballers ran for 5 min on a treadmill at speeds of 9, 10.5, 12 and 13.5km ·h –1 while dribbling a football against a rebound box; running at each of these speeds without the ball constituted controls. Oxygen uptake ([Vdot]O 2 ), perceived exertion (RPE) and blood lactate levels were measured and compared between the two conditions. The energy expended increased linearly with speed for both exercise modes, the mean increment of 1.24 kcal·min –1 caused by dribbling being independent of the speed of motion. Individual differences in efficiency of dribbling could not be explained by considering different patterns of stride characteristics. Similarly, RPE showed a constant elevation for dribbling over running at each speed, and a linear increase with speed of motion for both modes. Blood lactate increased disproportionately with speed for dribbling, onset of metabolic acidosis being attained at a lower speed for the experimental task. It was concluded that dribbling a ball does significantly increase the energy cost and perceived exertion of motion, as well as inducing disproportionate rises in blood lactate when performed at high speeds.  相似文献   
50.
等摩尔连续变化法测定瓜环包结配合物的包结比   总被引:1,自引:0,他引:1  
讨论了等摩尔连续变化法测定瓜环包结配合物包结比的理论依据,并利用紫外吸收光谱和荧光光谱测定了七、八元瓜环(Q [7],Q[8])与α-萘胺(q1)、β-萘胺(q1)两种异物体相互作用形成包结配合物的包结比。实验结果表明:等摩尔连续变化法较摩尔比法结果更清晰、更准确。七元瓜环与两种萘胺异构体只能形成1:1的包结,八元瓜环与苯胺两种异构体则形成1:2的包结。  相似文献   
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