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31.
PurposeThis study investigates the affective technology acceptance model applied to the case of blockchain through Twitter text mining.Design/methodology/approachThe analysis focuses on mapping the acceptance drivers of the blockchain technology by visualizing the users perception constructs through Blockchain hashtags. More than 5000 relevant tweets per day were collected between December 15, 2020, and January 15, 2021. The Kruskal-Wallis and the Mann-Whitney tests were applied over the frequency of the characteristics and the emotions' measurements to validate the research hypotheses.FindingsThe results prove that users show more interest in security, shareability, and decentralization characteristics. Therefore, the blockchain technology usefulness is rather perceived in the informational domain, and the blockchain ease of use is further expressed in smart contracts as a use case. Blockchain benefits are more discussed than the drawbacks among Twitter users. Besides, positive feelings with strong emotions of trust and joy dominate among users. In summary, the results show significant awareness of users towards blockchain technology.OriginalityTo the best of the authors' knowledge, this paper is the first study that explores the affective technology acceptance model with user-generated content analysis.  相似文献   
32.
The purpose of this study was to compare the effects of pre-exercise ice slurry ingestion and cold water immersion on submaximal running time in the heat. On three separate occasions, eight males ran to exhaustion at their first ventilatory threshold in the heat (34.0 ± 0.1 ° C, 52 ± 3% relative humidity) following one of three 30 min pre-exercise manoeuvres: (1) ice slurry ingestion; (2) cold water immersion; or (3) warm fluid ingestion (control). Running time was longer following cold water immersion (56.8 ± 5.6 min; P = 0.008) and ice slurry ingestion (52.7 ± 8.4 min; P = 0.005) compared with control (46.7 ± 7.2 min), but not significantly different between cold water immersion and ice slurry ingestion (P = 0.335). During exercise, rectal temperature was lower with cold water immersion from 15 and 20 min into exercise compared with control and ice slurry ingestion, respectively, and remained lower until 40 min (P = 0.001). At exhaustion rectal temperature was significantly higher following ice slurry ingestion (39.76 ± 0.36 ° C) compared with control (39.48 ± 0.36 ° C; P = 0.042) and tended to be higher than cold water immersion (39.48 ± 0.34 ° C; P = 0.065). As run times were similar between conditions, ice slurry ingestion may be a comparable form of pre-cooling to cold water immersion.  相似文献   
33.
Using a controlled parallel group longitudinal trial design, we investigated the effects of different training interventions on the prooxidant/antioxidant status of elite athletes: living and training at moderate altitude for 3 (Hi-Hi3) and 4 weeks (Hi-Hi), and for 4 weeks too, living high and training high and low (Hi-HiLo) and living and training at sea level (Lo-Lo). From 61 swimmers, 54 completed the study. Nitrites, carbonyls, and lipid peroxidation (LPO) levels were assessed in plasma. Enzymatic antioxidants glutathione peroxidase (GPx) and glutathione reductase (GRd), and non-enzymatic antioxidants total glutathione (GST), reduced glutathione (GSH) and oxidized glutathione (GSSG) were analysed in the erythrocyte fraction. At the end of the intervention, nitrites levels were similar in all altitude groups but higher than in the Lo-Lo controls (P?=?.02). Hi-HiLo had greater GPx activity than Hi-Hi and Hi-Hi3 during most of the intervention (P?≤?.001). GRd activity was higher in Lo-Lo than in Hi-Hi at the end of the training camp (P?≤?.001). All groups showed increased levels of LPO, except Lo-Lo, and carbonyls at the end of the study (P?≤?.001). Training at altitude for 3 or 4 weeks drives oxidative stress leading to cellular damage mainly by worsening the antioxidant capacities. The GSSG/GSH ratio appears to be related to perceived exertion and fatigue. The stronger antioxidant defence showed by the Hi-HiLo group suggests an inverse relationship between redox alterations and performance. Further studies are required to investigate the role of oxidative stress in acclimatization, performance, and health.  相似文献   
34.
Identifying the future influential papers among the newly published ones is an important yet challenging issue in bibliometrics. As newly published papers have no or limited citation history, linear extrapolation of their citation counts—which is motivated by the well-known preferential attachment mechanism—is not applicable. We translate the recently introduced notion of discoverers to the citation network setting, and show that there are authors who frequently cite recent papers that become highly-cited in the future; these authors are referred to as discoverers. We develop a method for early identification of highly-cited papers based on the early citations from discoverers. The results show that the identified discoverers have a consistent citing pattern over time, and the early citations from them can be used as a valuable indicator to predict the future citation counts of a paper. The discoverers themselves are potential future outstanding researchers as they receive more citations than average.  相似文献   
35.
Comprehensive sexuality education which includes discussion about gender and power is increasingly seen as an effective way of promoting sexual and reproductive health and rights. Yet all too often the potential of good quality sexuality education is not realised. This study engages with young peoples’ evaluation of a sexuality education programme in Ethiopia. Using data from ethnographic field notes, focus group discussions and interviews with students, teachers and sexual and reproductive health workers in Oromia region, it reveals the existence of gendered practices in sexuality education. Three forms of exclusion were evident: first, exclusion through selection to participate in the programme; second, exclusion of the views of young people through gendered interpretations and practices; third, exclusion of the views of young people through the omission of discussion on topics that are relevant to them, such as love, relationships and sexual intercourse. As a result, the programme’s potential to contribute to questioning gender relations and improving the emotional and sexual health of young people is undermined. The programme reproduces a gender order in school and arguably broader society, which is a source of frustration and alienation for young people.  相似文献   
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37.
This study investigated the two different time-of-day effect on team-handball-related short-term maximal physical performances. At two different time-of-day, fifteen young female team handball players performed different physical tests: HandGrip (HG) test, Ball-Throwing Velocity (BTV) test, Modified Agility T-test (MAT) and Repeated Shuttle-Sprint and Jump Ability (RSSJA) test. Rating of perceived exertion (RPE) scale was determined following the termination of the last test. Measurements were performed at two separate testing sessions (i.e., in the morning (7:00–8:30 h) and in the early evening (17:00–18:30 h)) in a randomised and counter-balanced setting on non-consecutive days. The results showed that HG (= 0.0013), BTV (= 0.0027) and MAT (< 0.001) performances were better in the evening compared with the morning. During RSSJA, both best and mean sprint times were shorter in the evening compared to the morning (< 0.001). Moreover, during the latter test, mean jump performance was higher in the evening compared to the morning (= 0.026). However, there was no morning–evening difference in the best jump performance during RSSJA. Likewise, jump performance decrement was not affected by the time-of-day of testing. On the other hand, RPE fluctuated, with morning nadirs and afternoon/early evening highest values. The findings suggest that in female team handball players, team-handball-related short-term maximal physical performances were better in the afternoon than in the morning.  相似文献   
38.
Extinction of a conditioned palatability shift preceded extinction of conditioned taste avoidance whether rats were tested using a within-subjects design or a between-subjects design. In each of two experiments, consumption of 0.1% saccharin was paired with either 20 ml/kg of 0.15 M LiCl or equivolume physiological saline on a single trial. In Experiment 1, on each of 10 extinction trials, rats were given a taste reactivity test immediately prior to a consumption test. In Experiment 2, half of the rats were extinguished by taste reactivity testing and half of the rats were extinguished by a consumption test on each of 10 extinction trials. In both experiments, the aversive reactions of gaping and passive dripping were extinguished in a single trial and the suppression of ingestive reactions was extinguished in 2 trials; however, extinction of taste avoidance required 4–5 trials. These results suggest that rats continue to avoid a lithium-paired flavor even when they do not have an aversion to the taste.  相似文献   
39.
The main aim of this study was to assess the physiological responses of male basketball players during usual basketball ball-drills. Fourteen male basketball players (age 18.9 ± 2.3 years) performed the following full-court (28 × 15 m) basketball ball-drills (3 × 4-min with 3-min passive rest): five-a-side (5v5), three-a-side (3v3) and two-a-side (2v2). A main effect (P < 0.0001) for ball-drills modes was evident for all variables (5v5 < 3v3 < 2v2). Mean [Vdot]O(2) during the 5v5, 3v3 and 2v2 were 39.0 ± 7.2, 42.0 ± 7.5 and 45.0 ± 6.5 ml · kg(-1) · min(-1) (69 ± 11, 74 ± 12 and 79 ± 11% of [Vdot]O(2peak)) respectively (5v5 = 3v3 < 2v2, P < 0.001). Mean blood-lactate concentrations for 5v5, 3v3 and 2v2 were 4.2 ± 1.8, 6.2 ± 2.3 and 7.8 ± 1.2 mmol (l(-1) respectively (5v5 < 3v3 < 2v2, P < 0.01). During the 5v5, 3v3 and 2v2 mean heart-rate (HR) was 84.0 ± 9.2, 88.0 ± 8.4 and 92.0 ± 5.6% of the individual peak respectively (5v5 < 3v3 < 2v2; P < 0.001). No significant differences were found between the regression-line slope (P = 0.86) and intercept (P = 0.45) of the HR-[Vdot]O(2) relationships of the multistage maximal fitness test (r(2) from 0.80 to 0.96, P < 0.001) and ball-drills (r(2) from 0.70 to 0.95, P < 0.001) conditions. Reducing the number of players over the same playing court resulted in increments in physiological demands. The 2v2 condition provided responses in the range of those reported to improve aerobic and anaerobic fitness. The aerobic demands of ball-drills can be accurately assessed using heart-rate monitoring in basketball.  相似文献   
40.
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