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Marco?A.?HaanEmail author S.?Gerhard?Dijkstra Peter?T.?Dijkstra 《Journal of Cultural Economics》2005,29(1):59-78
For centuries, there have been discussions as to whether only experts can judge the quality of cultural output, or whether the taste of the public also has merit. This paper tries to answer that question empirically, using national finals of the Eurovision Song Contest. We show that experts are better judges of quality in the sense that the outcome of finals judged by experts is less sensitive to factors unrelated to quality than the outcome of finals judged by public opinion. Yet, experts are not perfect; their judgment does still depend on such factors. This is also the case in the European finals of the contest. 相似文献
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195.
Electrosprays are a powerful technique to generate charged micro/nanodroplets. In the last century, the technique has been extensively studied, developed, and recognized with a shared Nobel price in Chemistry in 2002 for its wide spread application in mass spectrometry. However, nowadays techniques based on microfluidic devices are competing to be the next generation in atomization techniques. Therefore, an interesting development would be to integrate the electrospray technique into a microfluidic liquid-liquid device. Several works in the literature have attempted to build a microfluidic electrospray with disputable results. The main problem for its integration is the lack of knowledge of the working parameters of the liquid-liquid electrospray. The “submerged electrosprays” share similar properties as their counterparts in air. However, in the microfluidic generation of micro/nanodroplets, the liquid-liquid interfaces are normally stabilized with surface active agents, which might have critical effects on the electrospray behavior. In this work, we review the main properties of the submerged electrosprays in liquid baths with no surfactant, and we methodically study the behavior of the system for increasing surfactant concentrations. The different regimes found are then analyzed and compared with both classical and more recent experimental, theoretical and numerical studies. A very rich phenomenology is found when the surface tension is allowed to vary in the system. More concretely, the lower states of electrification achieved with the reduced surface tension regimes might be of interest in biological or biomedical applications in which excessive electrification can be hazardous for the encapsulated entities. 相似文献
196.
Silva DA Benedetti TR Ferrari EP Meurer ST Antes DL Silva AM Santos DA Matias CN Sardinha LB Vieira F Petroski EL 《Journal of sports sciences》2012,30(5):479-484
The objective of this study was to describe the anthropometric profiles of elite older triathletes participating in the 2009 Ironman Brazil and to compare their somatotype, anthropometric and body composition characteristics with those of elite young triathletes and older non-athletes. The sample consisted of 64 males, divided into three groups: (1) older triathletes (n = 17), (2) young triathletes (n = 24), and (3) older non-athletes (n = 23). Somatotype was analysed according to the Carter and Heath ( 1990 ) method. Body mass index, sum of four skinfolds, percentage body fat, body fat mass, and fat-free mass were also estimated. Older non-athletes had higher endomorphy, sum of four skinfolds, fat percentage, and body fat mass than the athletes. Older athletes who participated in the Ironman and elite young triathletes had higher fat-free mass than older non-athletes. Older triathletes and older non-athletes were considered mainly endomorphic mesomorphs and young triathletes mainly ectomorphic mesomorphs. The findings that characterize the anthropometric profile of athletes in this sports modality could be used as a reference. 相似文献
197.
Miarka B Panissa VL Julio UF Del Vecchio FB Calmet M Franchini E 《Journal of sports sciences》2012,30(9):899-905
The aim of this study was to compare time-motion indicators during judo matches performed by athletes from different age groups. The following age groups were analysed: Pre-Juvenile (13-14 years, n = 522), Juvenile (15-16 years, n = 353); Junior (19 years, n = 349) and Senior (>20 years, n = 587). The time-motion indicators included: Total Combat Time, Standing Combat Time, Displacement Without Contact, Gripping Time, Groundwork Combat Time and Pause Time. Analysis of variance (ANOVA) one-way and the Tukey test, as well as the Kruskal-Wallis test and Mann-Whitney (for non-parametric data), were conducted, using P < 0.05 as significance level. The results showed that all analysed groups obtained a median of 7 (first quantile - 3, third quantile - 12) sequences of combat/pause cycles. In total time of combat, the result was: for Total Combat Time, Standing Combat Time and Gripping Time: Pre-Juvenile and Senior were significantly longer than Juvenile and Junior. Considering Displacement Without Contact, Junior was significantly longer than all other age groups. For Groundwork Combat Time, Senior was significantly longer than all other age groups and Pre-Juvenile was longer than Junior. These results can be used to improve the physiological performance in intermittent practices, as well as technical-tactical training during judo sessions. 相似文献
198.
All traumatic and overuse injuries occurring during an average period of 4 years (2002/09) in a group of 51 currently active road top-level cyclists were retrospectively registered through clinical interviews. Average age was 25.8 years. Average training and competition period was 28.3 ± 2.4 h a week. Only 8 cyclists (15.6%) were completely free from lesions during the period of study. The remaining 43 cyclists suffered a total of 112 lesions; however, 9 out of these were unrelated to their cycling practice. These 103 cycling-related injuries include 50 (48.5%) traumatic and 53 (51.5%) overuse injuries. Twenty-eight fractures were reported, the clavicle being the most frequently affected bone (11 cases). The 68.5% of overuse injuries were located in the lower limbs. Most overuse injuries (89.6%) occurred during the training period. According to the injury abbreviated scale (AIS), severe lesions were only found in 4 cases (8% of traumatic injuries). Overall injury rates were 0.50 per racer/year, 2.02 per studied racer, and 0.007 per 1000 km of training and competition. Active professional top-level cyclists are exposed to a high injury risk. According to the scarce previously published data the current study provides relevant information on the injury occurrence of still active top-level road cycling. 相似文献
199.
M Martín-Matillas FB Ortega JR Ruiz D Martínez-Gómez G Vicente-Rodríguez A Marcos L Béghin A Kafatos M González-Gross M Zaccaria D Molnár S De Henauw M Sjöström LA Moreno MJ Castillo On Behalf Of The Helena Study 《Journal of sports sciences》2012,30(13):1329-1335
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?0.05); and mother's and sisters' physical activity engagement were positively associated with higher muscular strength in adolescents (P?0.05). Furthermore, father's physical activity encouragement was positively linked to physical fitness (all fitness components) in adolescents (P?0.05). Interventions aimed at improving physical fitness in young people might be more successful when family members, particularly mothers and fathers, are encouraged to engage in physical activity and support adolescents' physical activity. 相似文献
200.
目的观察火针治疗前后大鼠跟腱末端区细胞凋亡情况的变化,探讨火针治疗末端病的作用机理,为末端病的火针治疗提供理论依据。方法采用"电击跳跃法"建立大鼠跟腱末端病模型,施以火针治疗,采用TUNEL法检测细胞凋亡指数(AI)。结果(1)1次火针治疗后,治疗组大鼠末端区主要在跟腱、纤维软骨区、腱围这三个部位的AI比对照组有不同程度降低;(2)经4次火针治疗后,跟腱、纤维软骨区、腱骨关节面软骨、腱围的AI明显低于对照组;(3)4次火针治疗后在跟腱、纤维软骨区、腱骨关节面软骨、腱围的AI明显低于1次火针治疗组。结论(1)8周的"电击跳跃法"成功建立了大鼠跟腱末端病模型。(2)1次火针治疗可以减少末端区的细胞凋亡和修复已凋亡的细胞。(3)4次火针治疗不仅使末端区的凋亡细胞得到修复,而且加速了整个末端区组织和结构的恢复。 相似文献