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51.
52.
Don K. Price 《Minerva》1988,26(3):416-428
Conclusion The social sciences stand at a strange crossroads. There is a greater need for disciplined inquiry into the issues of policy facing the United States. Yet the incentives in the political system, and in the professional guilds of those performing social research, discourage a close involvement of many prominent social scientists with policy. The political system, fearing an elite imposing its values on society, welcomes the natural scientist who seems to conform to the model of the politically neutral expert who solves problems and addresses facts. This model also fits the higher ranks of the civil service, made up of specialists rather than generalist administrators, and the outside advisers serving officials concerned with high policy. Likewise, to protect themselves from changes of partisanship, leading academic social scientists forsake policy concerns for topics within the analytic traditions of Weberian Wertfreiheit. Just as Weber sought to avoid censorship by value neutral scholarship, the modern social scientist disdains the normative concerns of policy in favour of more tractable, morally neutral issues defined as the core of the discipline.The country needs to draw some of the best analytical talent in the social science community into the policy process and advisory roles. Disciplined inquiry cannot be left only to technicians whose professional interests are far removed from political, economic, social and other human sciences. To promote better policy and better social science, we should encourage serious, professionally grounded inquiry into social values, the directions of policy, and the role and proper limits of state power. In the clamour of American politics, there is little danger that policy will be monopolised by an elite group, but considerable danger that debate on policy will be impoverished by the absence of those most knowledgeable about social and economic reality.A revised and expanded version of the first Dael L. Wolfle Lecture given on 6 October, 1987, at the Graduate School of Public Affairs, University of Washington, Seattle. Don K. Price was dean of the John F. Kennedy School of Government, Harvard University, and is the author ofGovernment and Science (1954),The Scientific Estate (1965) andAmerica's Unwritten Constitution (1983). He has held senior posts in the United States Bureau of the Budget, the Defense Research and Development Board, and the Ford Foundation, and was an adviser to Presidents Eisenhower, Kennedy and Johnson. 相似文献
53.
This paper analyses the popular RateMyProfessors (RMP) website where students evaluate instructors in higher education. A study was designed to measure (1) the awareness and utilisation of the RMP website, (2) the internal and external validity of the RMP ratings in measuring teaching effectiveness, and (3) variation in the above across disciplines. It is concluded that the category of ratings, created by the website, establishes an anti‐intellectual tone that manifests itself in comments about instructors’ personality, easiness of workload and entertainment value rather than knowledge attained. 相似文献
54.
55.
The Effect of Two-dimensional and Stereoscopic Presentation on Middle School Students’ Performance of Spatial Cognition Tasks 总被引:1,自引:1,他引:0
We investigated whether and how student performance on three types of spatial cognition tasks differs when worked with two-dimensional
or stereoscopic representations. We recruited nineteen middle school students visiting a planetarium in a large Midwestern
American city and analyzed their performance on a series of spatial cognition tasks in terms of response accuracy and task
completion time. Results show that response accuracy did not differ between the two types of representations while task completion
time was significantly greater with the stereoscopic representations. The completion time increased as the number of mental
manipulations of 3D objects increased in the tasks. Post-interviews provide evidence that some students continued to think
of stereoscopic representations as two-dimensional. Based on cognitive load and cue theories, we interpret that, in the absence
of pictorial depth cues, students may need more time to be familiar with stereoscopic representations for optimal performance.
In light of these results, we discuss potential uses of stereoscopic representations for science learning. 相似文献
56.
The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption ( V O 2peak ) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev·min -1 . The order of tests was randomized and they were separated by at least 2 days. Peak V O 2 was significantly higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Peak ventilation volume increased as a function of crank rate and was higher ( P ? 0.05) at 80 than at 60 rev·min -1 . Peak heart rate was higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Furthermore, 70 and 80 rev·min -1 resulted in an extended test time compared with 60 rev·min -1 . The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev·min -1 should be used to elicit V O 2peak and other physiological responses in arm crank ergometry. 相似文献
57.
The thermoregulatory responses of upper-body trained athletes were examined at rest, during prolonged arm crank exercise and recovery in cool (21.5 ± 0.9°C, 43.9 ± 10.1% relative humidity; mean ± s) and warm (31.5 &± 0.6°C, 48.9 - 8.4% relative humidity) conditions. Aural temperature increased from rest by 0.7 ± 0.7°C (P ? 0.05) during exercise in cool conditions and by 1.6 ± 0.7°C during exercise in warm conditions (P ? 0.05). During exercise in cool conditions, calf skin temperature decreased (1.5 ± 1.3°C), whereas an increase was observed during exercise in warm conditions (3.0 ± 1.7°C). Lower-body skin temperatures tended to increase by greater amounts than upper-body skin temperatures during exercise in warm conditions. No differences were observed in blood lactate, heart rate or respiratory exchange ratio responses between conditions. Perceived exertion at 45 min of exercise was greater than that reported at 5 min of exercise during the cool trial (P ? 0.05), whereas during exercise in the warm trial the rating of perceived exertion increased from initial values by 30 min (P ? 0.05). Heat storage, body mass losses and fluid consumption were greater during exercise in warm conditions (7.06 ± 2.25 J·g-1 ·°C-1, 1.3 ± 0.5 kg and 1038 ± 356 ml, respectively) than in cool conditions (1.35 ± 0.23 J·g-1·°C-1, 0.8 ± 0.2 kg and 530 ± 284 ml, respectively; P ? 0.05). The results of this study indicate that the increasing thermal strain with constant thermal stress in warm conditions is due to heat storage within the lower body. These results may aid in understanding thermoregulatory control mechanisms of populations with a thermoregulatory dysfunction, such as those with spinal cord injuries. 相似文献
58.
This study examined the effects of different work?–?rest durations during 40?min intermittent treadmill exercise and subsequent running performance. Eight males (mean?±?s: age 24.3?±?2.0 years, body mass 79.4?±?7.0?kg, height 1.77?±?0.05?m) undertook intermittent exercise involving repeated sprints at 120% of the speed at which maximal oxygen uptake (v-[Vdot]O2max) was attained with passive recovery between each one. The work?–?rest ratio was constant at 1:1.5 with trials involving short (6:9?s), medium (12:18?s) or long (24:36?s) work?–?rest durations. Each trial was followed by a performance run to volitional exhaustion at 150% v-[Vdot]O2max. After 40?min, mean exercise intensity was greater during the long (68.4?±?9.3%) than the short work?–?rest trial (54.9?±?8.1% [Vdot]O2max; P?<?0.05). Blood lactate concentration at 10?min was higher in the long and medium than in the short work?–?rest trial (6.1?±?0.8, 5.2?±?0.9, 4.5?±?1.3?mmol?·?l?1, respectively; P?<?0.05). The respiratory exchange ratio was consistently higher during the long than during the medium and short work?–?rest trials (P <?0.05). Plasma glucose concentration was higher in the long and medium than in the short work?–?rest trial after 40?min of exercise (5.6?±?0.1, 6.6?±?0.2 and 5.3?±?0.5?mmol?·?l?1, respectively; P?<?0.05). No differences were observed between trials for performance time (72.7?±?14.9, 63.2?±?13.2, 57.6?±?13.5?s for the short, medium and long work?–?rest trial, respectively; P = 0.17), although a relationship between performance time and 40?min plasma glucose was observed (P?<?0.05). The results show that 40?min of intermittent exercise involving long and medium work?–?rest durations elicits greater physiological strain and carbohydrate utilization than the same amount of intermittent exercise undertaken with a short work?–?rest duration. 相似文献
59.
60.
Abstract In this study, we examined the effects of different work:rest durations during 20 min intermittent treadmill running and subsequent performance. Nine males (mean age 25.8 years, s = 6.8; body mass 73.9 kg, s = 8.8; stature 1.75 m, s = 0.05; [Vdot]O2max 55.5 ml · kg?1 · min?1, s = 5.8) undertook repeated sprints at 120% of the speed at which [Vdot]O2max was attained interspersed with passive recovery. The work:rest ratio was constant (1:1.5) with trials involving either short (6:9 s) or long (24:36 s) work:rest exercise protocols (total exercise time 8 min). Each trial was followed by a performance run to volitional exhaustion at the same running speed. Testing order was randomized and counterbalanced. Heart rate, oxygen consumption, respiratory exchange ratio, and blood glucose were similar between trials (P > 0.05). Blood lactate concentration was greater during the long than the short exercise protocol (P < 0.05), whereas blood pH was lower during the long than the short exercise protocol (7.28, s = 0.11 and 7.30, s = 0.03 at 20 min, respectively; P < 0.05). Perceptions of effort were greater throughout exercise for the long than the short exercise protocol (16.6, s = 1.4 and 15.1, s = 1.6 at 20 min, respectively; P < 0.05) and correlated with blood lactate (r = 0.43) and bicarbonate concentrations (r = ?0.59; P < 0.05). Although blood lactate concentration at 20 min was related to performance time (r = ?0.56; P < 0.05), no differences were observed between trials for time to exhaustion (short exercise protocol: 95.8 s, s = 30.0; long exercise protocol: 92.0 s, s = 37.1) or physiological responses at exhaustion (P > 0.05). Our results demonstrate that 20 min of intermittent exercise involving a long work:rest duration elicits greater metabolic and perceptual strain than intermittent exercise undertaken with a short work:rest duration but does not affect subsequent run time to exhaustion. 相似文献