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51.
This paper presents the results of a study to determine the effect of the presence of a public junior college in a community upon the types of colleges attended by high school graduates of that community. Results of multivariate cross-tabular analysis of the college destinations of over 8,000 1966 Illinois high school seniors of different sex, ability, and social-status backgrounds living in 25 different communities, suggest that the local availability of a public junior college serves largely to alter patterns of college-going by substituting attendance locally for attendance elsewhere in a manner inversely related to social status. More importantly, results also suggest that among lower- and middle-status persons the substitution is such as to replace attendance at nonlocal four-year colleges with attendance locally at the public junior college.  相似文献   
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Physical profile data from elite, sub-elite, regional, under 21s (U21), under 19s (U19) and under 17s (U17) (n = 845) players from a state netball association in Australia were analysed. Within season changes were examined for the elite and sub-elite players. Longitudinal changes were examined for the elite across four consecutive netball seasons.

Elite were significantly older (24.3 ± 3.4years), taller (182.4 ± 7.2cm) and heavier (73.42 ± 6.95kg) than other playing levels (p < 0.001, ES 0.49–3.26) and had higher vertical jump (VJ) data compared to all groups (p < 0.001, ES 0.47–0.93). U17’s were significantly faster than elite, sub-elite and U19 players over 5m (p < 0.05, ES 0.36–0.58) while elite were faster over 20m compared to all groups (p < 0.01, ES 0.45–0.72). Elite achieved a greater distance (1350.8m; p < 0.05, ES 0.32–0.50) in the Yo-YoIRT1 compared to the sub-elite, regional, U19 and U17. VJ height significantly increased from the 2014 (51.6 ± 4.8cm) to the 2017 season (59.6 ± 6.3cm) for the elite players (p < 0.01, ES 1.18). Yo-YoIRT1 test scores increased significantly between the pre-season and in-season phases (p < 0.05, ES 0.17).  相似文献   

54.
The protective action of remote ischaemic preconditioning (RIPC) has been demonstrated in the context of surgical interventions in cardiology. Application of RIPC to sports performance has been proposed, but its effect on the electrocardiogram (ECG) during exercise remains unknown. This exploratory study aims to measure the changes in ventricular repolarization observed during exercise following RIPC in healthy subjects. In an experimental randomized crossover study, 17 subjects underwent two bouts of constant load exercise tests at 75% and 115% of gas exchange threshold (GET). Prior to exercise, they were allocated to either control or RIPC intervention with four cycles of 5?min of ischaemia followed by 5?min of reperfusion. ECG was continuously recorded during the protocol. QT and RR intervals were measured every 30?s (on an average tracing of the preceding 10?s). Although the time course of RR intervals did not differ between the two interventions (p?=?.56 at 75% GET and p?=?.74 at 115% GET), a significant shortening of QT intervals (measured from Q onset to T end) was observed during exercise (mean?±?standard deviation of RIPC vs. control: ?32?±?19?ms at 75% GET (p?p?p?p?相似文献   
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56.
Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position.  相似文献   
57.
Research into sighted children’s reading shows that letter recognition skill predicts phonological awareness skill. Congenitally–blind children do not receive exposure to environmental print and do not generally learn to recognise written letters of the alphabet prior to schooling in Braille. A cross–sectional analysis revealed that blind children with no knowledge of written letters or written words showed no ability at measures of phonological awareness. Blind children with knowledge of written letters and no written words showed much increased phonological awareness scores and blind children with knowledge of written letters and written words scored higher still on phonological awareness measures. It was concluded that letter learning is a major contributor to the development of phonological awareness in blind children. It suggests key similarities in the underlying processes of reading development across two different populations using different modalities to learn to read.  相似文献   
58.
Understanding that mathematics is founded on reasoning and is not just a collection of rules to apply is an important message to convey to students. Here we examined the reasoning presented in seven topics in nine Australian eighth-grade textbooks. Focusing on explanatory text that introduced new mathematical rules or relationships, we classified explanations according to the mode of reasoning used. Seven modes were identified, making a classification scheme which both refined and extended previous schemes. Most textbooks provided explanations for most topics rather than presenting “rules without reasons” but the main purpose appeared to be rule derivation or justification in preparation for practise exercises, rather than using explanations as thinking tools. Textbooks generally did not distinguish between the legitimacies of deductive and other modes of reasoning.  相似文献   
59.
Compared to isokinetic and isometric tests, isoinertial movements have been poorly used to assess single-joint performance. Two calculation procedures were developed to estimate mechanical performance during single-joint isoinertial movements performed on a customised isokinetic dynamometer. The results were also compared to appreciate the effects of measurement systems and calculation procedures. Five participants performed maximal knee extensions at four levels of resistance (30, 50, 70 and 90% of the one-repetition maximum, 1-RM). Joint angular velocity and torque were assessed from customised isokinetic dynamometer measures (method A) and from weight stack kinematic (method B). Bland–Altman plots and mean percent differences (Mdiff) were used to assess the level of agreement for mean and peak angular velocity and torque. A Passing–Bablok regression was performed to compare the angular velocity-angle and torque-angle relationships computed from the two analysis methods. The results showed a high level of agreement for all mechanical parameters (Mdiff < 6% for all parameters). No statistically significant differences were observed between methods A and B in terms of angular velocity-angle and torque-angle relationships except at 30% of 1-RM for the torque-angle relationship. Both methodologies provide comparable values of angular velocity and torque, offering alternative approaches to assess neuromuscular function from single-joint isoinertial movements.  相似文献   
60.
This paper explores the possible job creation effect of innovation activity. We analyze a unique panel dataset covering almost 20,000 patenting firms from Europe over the period 2003–2012. The main outcome from the proposed GMM-SYS estimations is the labor-friendly nature of innovation, which we measure in terms of forward-citation weighted patents. However, this positive impact of innovation is statistically significant only for firms in the high-tech manufacturing sectors, while not significant in low-tech manufacturing and services.  相似文献   
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