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51.
Governmental initiatives around scientific policy have progressively raised collaboration to priority status. In this context, a need has arisen to broaden the traditional approach to the analysis and study of research results by descending to the group or even the individual scale and supplementing the output-, productivity-, visibility- and impact-based focus with new measures that emphasize collaboration from the vantage of structural analysis. To this end, the present paper proposes new hybrid indicators for the analysis and evaluation of individual research results, popularity and prestige, that combine bibliometric and structural aspects. A case study was conducted of the nine most productive departments in Carlos III University of Madrid. The findings showed hybridization to be a tool sensitive to traditional indicators, but also to the new demands of modern science as a self-organized system of interaction among individuals, furnishing information on researchers’ environments and the behaviour and attitudes adopted within those environments.  相似文献   
52.
Online education based on small self‐managing groups, with slight supervision by a professional tutor, is a strategically interesting methodology for lifelong learning. This solution may combine aspects of cost‐effectiveness (reducing tutors' work) with the demands for active and engaging learning methods based on the exchange and sharing of experiences. In such a context, how can information on collaborative attitudes and behaviour be gathered? A typical tool for online learning activities is the threaded web forum. This study proposes a methodology for assessing effective collaborative interactions within the add‐on module, Forum Plus, for the Moodle learning management system (LMS). The methodology here presented is able to supply an early overview of the level of effectiveness of the collaborative group and therefore it may provide a useful instrument to guide further qualitative observations conducted directly in the web forum.  相似文献   
53.
This study compared the effects of two velocity loss thresholds during a power-oriented resistance training program on the mechanical capacities of lower-body muscles. Twenty men were counterbalanced in two groups (VL10 and VL20) based on their maximum power capacity. Both groups used the same exercises, relative intensity and repetition volume, only differing in the velocity loss threshold of each set (VL10: 10% vs. VL20: 20%). Pre- and post-training assessments included an incremental loading test and a 15-m linear sprint to assess the force- and load-velocity relationships and athletic performance variables, respectively. No significant between-group differences (P > 0.05) were observed for the force-velocity relationship parameters (ES range = 0.15–0.42), the MPV attained against different external loads (ES range = 0.02–0.18) or the 15-m sprint time (ES = 0.09). A high between-participants variability was reported for the number of repetitions completed in each training set (CV = 30.3% for VL10 and 29.4% for VL20). These results suggest that both velocity loss thresholds induce similar changes on the lower-body function. The high and variable number of repetitions completed may compromise the velocity-based approach for prescribing and monitoring the repetition volume during a power-oriented resistance training program conducted with the countermovement jump exercise.  相似文献   
54.
In this paper we propose a new event generator, which has strong noise-filtering capabilities, to be used in event-based control systems with a PIDPlus controller. An approximate frequency analysis is performed in order to characterize the event generator system and tuning guidelines are provided for its design parameter. Simulation and experimental results obtained with a laboratory setup demonstrate the effectiveness of the methodology in providing a satisfactory performance related to set-point and load disturbance step responses with a total variation that is significantly reduced with respect to the standard cases.  相似文献   
55.
Business cycles modify firms’ incentives to innovate and the direction of innovation. By introducing a new measure of patent unconventionality this paper explores the impact of the business cycle on firms’ technological search strategies. We find that during upturns firms generate inventions characterized by a higher level of technological unconventionality. We also find that financially resilient and diversified firms produce more unconventional patents. While patent unconventionality is associated with technological impact and market value, firms extract more value by investing in unconventional inventions in downturns.  相似文献   
56.
We investigated whether low-level laser therapy (LLLT) prior to or post resistance exercise could attenuate muscle damage and inflammation. Female Wistar rats were assigned to non-LLLT or LLLT groups. An 830-nm DMC Laser Photon III was used to irradiate their hind legs with 2J, 4J, and 8J doses. Irradiations were performed prior to or post (4J) resistance exercise bouts. Resistance exercise consisted of four maximum load climbs. The load work during a resistance exercise bout was similar between Control (non-LLLT, 225 ± 10 g), 2J (215 ± 8 g), 4J (210 ± 9 g), and 8J (226 ± 9 g) groups. Prior LLLT did not induce climbing performance improvement, but exposure to 4J irradiation resulted in lower blood lactate levels post-exercise. The 4J dose decreased creatine kinase and lactic dehydrogenase levels post-exercise regardless of the time of application. Moreover, 4-J irradiation exposure significantly attenuated tumor necrosis factor alpha, interleukin-6, interleukin-1β, cytokine-induced neutrophil chemoattractant-1, and monocyte chemoattractant protein-1. There was minor macrophage muscle infiltration in 4J-exposed rats. These data indicate that LLLT prior to or post resistance exercise can reduce muscle damage and inflammation, resulting in muscle recovery improvement. We attempted to determine an ideal LLLT dose for suitable results, wherein 4J irradiation exposure showed a significant protective role.  相似文献   
57.
This study aimed to investigate the effect of contact (C-SSG) and no-contact (NC-SSG) handball small-sided games (SSGs) on motion patterns and physiological responses of elite handball players. Twelve male handball players performed 10 C-SSG and 10 NC-SSG while being monitored through the heart rate (HR) and rate of perceived exertion (RPE) as physiological responses and time-motion activities profile using video-match analysis. Both game conditions resulted in similar HR responses (> 0.05), but the NC-SSG led to a higher RPE scores. The time-motion activity analysis featured NC-SSG with a greater amount of walking (855.6 ± 25.1 vs. 690.6 ± 35.2 m) and backward movements (187.5 ± 12.3 vs. 142.5 ± 8.7 m) combined with fast running (232.3 ± 8.5 vs. 159.7 ± 5.7 m) and sprinting (79.5 ± 4.7 vs. 39.7 ± 3.7 m) activities (< 0.001). Conversely, C-SSG had a higher percentage of jogging and sideway movements associated with greater frequency of jumping (0.87 ± 0.09 vs. 0.31 ± 0.06 nr) and physical contact (1.82 ± 0.55 vs. 0.25 ± 0.03 nr) events (< 0.001). No between-regimen differences were found for the number of throws (= 0.745). In addition, the RPE was significantly correlated with fast running relative distances (= 0.909, < 0.001) and sprinting relative distances (= 0.939, < 0.001). In conclusion, this investigation showed that both C-SSG and NC-SSG in team handball can effectively represent specifically oriented exercises, according to the sport-task and the performance demands.  相似文献   
58.
Two important problems have been observed fairly frequently among information technology (IT) professionals, namely turn-over – where the IT professional moves to another company but still remains in the IT sector – and turn-away, in which the IT professional abandons the area in order to occupy a position in a different area, either in the same company or in another, sometimes assuming a managerial function. Few research papers were found with respect to the latter phenomenon. Based on that, the main thrust of this work is to understand how and why IT professionals in Brazil abandon their area, identifying typical characteristics in their career transition. Thus, from a literature review about career development and the analysis of the data collected, eight research hypotheses were developed in order to be analyzed by the researchers. A multiple case study method with several units of analysis was applied in two large companies in Brazil. In-depth interviews were conducted with IT professionals who had migrated to other areas within their organizations, they being considered the unit of analysis. The results accrued from this research reveal that IT professionals in Brazil need to have more growth opportunities than either their companies have been able to offer them or it is possible to offer within the technical arena.  相似文献   
59.
Abstract

The purpose of this study was to investigate the association between relay exchange block time and final performance in 4 × 100-m and 4 × 200-m freestyle and 4 × 100-m medley relays as a function of sex (men and women) and classification (medallists and non-medallists) in international competitions. Nineteen international competitions covering a 13-year period (2000–2012) were analysed retrospectively. The data corresponded to a total of 827 team relay histories (407 men, 420 women). Kruskal–Wallis and Mann–Whitney tests were performed to determine any differences by sex, classification, and event. Similarly, the relationship between the exchange block times and final performance was examined by means of a Pearson correlation analysis. In the three events, the men’s exchange block times were shorter than those of the women (η2 = 0.049–0.109; < 0.001). The exchange block time was especially relevant for the women’s relay medallists in the 4 × 100-m freestyle (= 0.306, = 0.021) and 4 × 100-m medley (= 0.385, = 0.011), while for men the relationship was clearer for the non-medallists. These results suggest that the exchange block time should be considered as one of the performance parameters of swimming relay starts, and thus should be included explicitly as part of training. In particular, the coach could design training targeted at standardising an optimal exchange block time equal to or less than that expected for other teams in the competition.  相似文献   
60.

Purpose: The purpose of this study was to examine the relative effectiveness of 2 forms of physical education instruction on students' skill and technical performance, as well as content knowledge in 3 track and field events. Method: Students from 6 classes in 3 Portuguese schools completed 900-min units conducted under the auspices of sport education or a more traditional teacher-directed format. Classes were randomly assigned to these conditions within each school. Results: Although both groups improved significantly from pretest to posttest, the sport education classes outperformed the traditional classes in both technique and skill execution. Only the sport education group made significant improvements in content knowledge. When the students in the traditional group were tested at the point in time where they would usually complete a unit of physical education (450 min), there were no significant improvements in any of the study's variables. Conclusion: The explanation given for the superior performance outcomes of the sport education classes lies in the nature of formal competition and team affiliation, which are cornerstones of this pedagogical model. That is, students take their learning experiences more seriously than in traditional and often inauthentic classes. In terms of content knowledge, the fact that sport education has a level of content-embedded accountability that holds students accountable for their officiating duties is postulated as a significant contributor to their increased understanding of rules and protocols of athletic events.  相似文献   
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