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71.
新媒体时代,纸媒期刊所能提供的基本服务已无法满足各类用户对信息的深层次需求和差异化要求.科技期刊如要在这一时代立足,应走与新媒体融合发展的道路,将传统期刊和新媒体各自优势相结合,为读者和作者提供精准服务,并通过互动实现多方共赢.文章介绍《药学进展》编辑部在微信群和微信订阅号运营中的实践经验,旨在为科技期刊利用微信平台服务读者和作者提供思路.  相似文献   
72.
Although the effectiveness of inoculation as a strategy for promoting resistance to attitude change is fairly well established, the potential of inoculation messages to offer cross-protection for related, but untreated, attitudes warrants additional attention from scholars. The reported study tested the “blanket of protection” conferred by inoculation. Participants (N = 118) were randomly assigned to read an inoculation message addressing a target topic and subsequently had their attitudes toward three related, but untreated, topics attacked. The results offer some evidence that inoculation messages can confer cross-protection for related attitudes. Participants in the inoculation condition reported greater perceptions of threat, greater counterarguing, and less attitude change in response to attacks than participants in the control condition for two of the three untreated topics. Counterarguing in response to attacks on untreated attitudes appears to be primarily responsible for cross-protection.  相似文献   
73.
Heavy training is associated with increased respiratory infection risk and antimicrobial proteins are important in defence against oral and respiratory tract infections. We examined the effect of 14 weeks of vitamin D3 supplementation (5000 IU/day) on the resting plasma cathelicidin concentration and the salivary secretion rates of secretory immunoglobulin A (SIgA), cathelicidin, lactoferrin and lysozyme in athletes during a winter training period. Blood and saliva were obtained at the start of the study from 39 healthy men who were randomly allocated to vitamin D3 supplement or placebo. Blood samples were also collected at the end of the study; saliva samples were collected after 7 and 14 weeks. Plasma total 25(OH)D concentration increased by 130% in the vitamin D3 group and decreased by 43% in the placebo group (both = 0.001). The percentage change of plasma cathelicidin concentration in the vitamin D3 group was higher than in the placebo group (= 0.025). Only in the vitamin D3 group, the saliva SIgA and cathelicidin secretion rates increased over time (both = 0.03). A daily 5000 IU vitamin D3 supplement has a beneficial effect in up-regulating the expression of SIgA and cathelicidin in athletes during a winter training period, which could improve resistance to respiratory infections.  相似文献   
74.
The aim of this study was to investigate how the type of contact influences physiological, perceptual and locomotive load during a simulated rugby league match. Eleven male university rugby league players performed two trials of the rugby league movement simulation protocol for interchange forwards with a traditional soft tackle bag and a weighted tackle sled to replicate contact demands. The interchange forward-specific simulation was chosen given the contact frequency is higher for this group of players compared to whole match players. Locomotive rate, sprint speed, tackle intensity, heart rate (HR) and rating of perceived exertion were analysed during the first and second bouts that replicated two ~23 min on-field passages. Countermovement jump (CMJ) was measured before and immediately after each trial. More time was spent in heart rate zone between 91 and 100% HRpeak during the first (effect size ± 90% confidence interval: 0.44 ± 0.49) and second bouts (0.44 ± 0.43), and larger (0.6 ± 0.69) decrements in CMJ performance were observed during the sled trial (5.9, = 4.9%) compared to the bag trial (2.6, = 5.4%). Changing the type of contact during the match simulation subtly altered both the internal and external loads on participants. Using a standard tackle bag results in faster sprint speed to contact, but lower overall high-intensity running. Conversely, a heavier tackle object increases the internal load and results in greater lower limb neuromuscular fatigue as reflected by the decrease in CMJ performance.  相似文献   
75.
The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids and body composition in overweight/obese women. Thirty women (mean ± SD; weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg · m2) were randomly assigned to ten 1-min high-intensity intervals (90%VO2 peak, 1 min recovery) or five 2-min high-intensity intervals (80–100% VO2 peak, 1 min recovery) or control. Peak oxygen uptake (VO2 peak), peak power output (PPO), body composition and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (P > 0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in PPO (?18.9 ± 8.5 watts; P = 0.014) and time to exhaustion (?55.1 ± 16.4 s; P = 0.001); non-significant increase in VO2 peak (?2.36 ± 1.34 ml · kg?1 · min?1; P = 0.185); and a significant decrease in fat mass (FM) (??1.96 ± 0.99 kg; P = 0.011). Short-term interval exercise training may be effective for decreasing FM and improving exercise tolerance in overweight and obese women.  相似文献   
76.
Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.  相似文献   
77.
1.Introduction The reproduction systems of 3D images without using eyeglasses and other special accessories has always attracted attention and aroused great interest of developers and consumers of such equipment because of totally accurate image and method of its presentation.Such systems can be used and are already partially used in advertising,television,different devices (i.e.smartphones,tablet computers),at the exhibitions,etc.,as well as in various technical applications,training systems,simulators,etc.  相似文献   
78.
This study examined the accuracy of self-attachment of the activPAL activity monitor. A convenience sample of 50 participants self-attached the monitor after being presented with written material only (WMO) and then written and video (WV) instructions; and completed a questionnaire regarding the acceptability of the instructional methods. Participants positioned the monitor lower than the instructed position on the thigh (WMO ?5.15 ± 2.75 cm, WV ?4.16 ± 2.15 cm; p = .008 difference) and approximately 2 cm laterally from the thigh midline (WMO 1.90 ± 0.92 cm; WV 2.08 ± 1.24 cm). The orientation of the device was positioned correctly along the midline (within < 1° of vertical). Acceptability was high for both instructional methods although preference was shown for the WV instruction. In conclusion, participants consistently self-attached the activPAL close to the intended placement with either instructional method. The addition of video instruction produced a slightly more accurate attachment and was preferred by the participants.  相似文献   
79.
Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost.  相似文献   
80.
This article reassesses The People's Choice by Paul Lazarsfeld, Bernard Berelson, and Hazel Gaudet, one of the foundations of communication and voting behavior research. As with most classics, which are often cited but seldom read, we believe this book has much to teach contemporary social scientists. We return to the original context of the research and use voting data from the period with three broad goals: (a) to find ideas and lessons from this work that generally have been overlooked, (b) to suggest new ways of applying these ideas, and (c) to encourage scholars to engage more with this seminal work to understand ideas that are often overlooked when a complex piece of research is reduced to a brief discussion or passing citation.  相似文献   
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