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21.
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   
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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   
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Lumbar-pelvic kinematics change in response to increasing rowing stroke rates, but little is known about the effect of incremental stroke rates on changes in joint kinetics and their implications for injury. The purpose of this study was to quantify the effects of incremental rowing intensities on lower limb and lumbar-pelvic kinetics. Twelve female rowers performed an incremental test on a rowing ergometer. Kinematic data of rowers’ ankle, knee, hip and lumbar-pelvic joints, as well as external forces at the handle, seat and foot-stretchers of the rowing machine were recorded. Inter-segmental moments and forces were calculated using inverse dynamics and were compared across stroke rates using repeated measures ANOVA. Rowers exhibited increases in peak ankle and L5/S1 extensor moments, reductions in peak knee moments and no change in peak hip moments, with respect to stroke rate. Large shear and compressive forces were seen at L5/S1 and increased with stroke rate (< 0.05). This coincided with increased levels of lumbar-pelvic flexion. High levels of lumbar-pelvic loading at higher stroke rates have implications with respect to injury and indicated that technique was declining, leading to increased lumbar-pelvic flexion. Such changes are not advantageous to performance and can potentially increase the risk of developing injuries.  相似文献   
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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   
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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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This study investigated whether or not the teaching of matched examples and nonexamples in the form of common errors would improve student performance in applying a procedure to previously unencountered instances, and whether the common errors would be most beneficial in generality form, in example form, or in both forms. Participants were 141 first-year music students, who were randomly assigned to four groups and given the task to learn a procedure that was presented in a self-contained booklet. A pretest-posttest experimental design was used, with a prerequisite test given as a screening device. The two independent variables were the absence and presence of the common errors in the generality form and in the example form (2 x 2 factorial design). Results indicated that the teaching of common errors in the generality form significantly improved learning a procedure at the application level of behavior.  相似文献   
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