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971.
Jörn H.B. Lengsfeld 《The Information Society》2013,29(3):141-157
Introducing an econometric approach to quantify the digital divide, this article presents a new method to facilitate crossnational and in-depth sectional analyses of the digital divide within a consistent framework. It examines the sociodemographic topology of the digital divide in an extensive crossnational analysis covering six sociodemographic factors and twenty-five countries. The findings contradict in part the conclusions of previous research. Although there are differences between the social groups, not all of the tested segmentation factors mark major fault lines of the digital divide. The notions of a gender gap, an income divide, and a divide between urban and rural areas are rejected because between-group disparity proves to be only minor in comparison to overall inequality. However, education, age, and main vocational activity do indeed mark digital boundaries in many of the observed countries. 相似文献
972.
Eeva-Leena Kataja Linnea Karlsson Jukka M. Leppänen Juho Pelto Tuomo Häikiö Saara Nolvi Henri Pesonen Christine E. Parsons Jukka Hyönä Hasse Karlsson 《Child development》2020,91(2):e475-e480
We examined how infants’ attentional disengagement from happy, fearful, neutral, and phase-scrambled faces at 8 months, as assessed by eye tracking, is associated with trajectories of maternal depressive symptoms from early pregnancy to 6 months postpartum (decreasing n = 48, increasing n = 34, and consistently low symptom levels n = 280). The sample (mother–infant dyads belonging to a larger FinnBrain Birth Cohort Study) was collected between 5/2013–6/2016. The overall disengagement probability from faces to distractors was not related to maternal depressive symptoms, but fear bias was heightened in infants whose mothers reported decreasing or increasing depressive symptoms. Exacerbated attention to fearful faces in infants of mothers with depressive symptoms may be independent of the timing of the symptoms in the pre- and postnatal stages. 相似文献
973.
Steven O. Roberts Arnold K. Ho Selin Gülgöz Jacqueline Berka Susan A. Gelman 《Child development》2020,91(3):e721-e732
Hypodescent emerged in U.S. history to reinforce racial hierarchy. Research suggests that among contemporary U.S. adults, hypodescent continues to shape social perception. Among U.S. children, however, hypodescent is less likely to be endorsed. Here, we tested for hypodescent by introducing U.S. children (ages 4–9) and adults (N = 273) to hierarchically ordered novel groups (one was high status and another was low status) and then to a child who had one parent from each group. In Study 1, we presented the groups in a third-party context. In Study 2, we randomly assigned participants to the high-status or the low-status group. Across both studies, participants did not reliably endorse hypodescent, raising questions as to what elicits this practice. 相似文献
974.
Brynley Crosado Sabine Löffler Benjamin Ondruschka Ming Zhang Johann Zwirner Niels Hammer 《Anatomical sciences education》2020,13(6):778-793
Embalming fixatives such as formaldehyde and phenol have been associated with occupational health hazards. While anatomists aim at replacing these chemicals, this seems presently unfeasible in particular for formaldehyde. Furthermore, fixation protocols usually require well-equipped facilities with highly experienced staff to achieve good fixation results in spite of only a minimal use of formaldehyde. Combining these aspects, a technique robust enough to be carried out by morticians is presented, resulting in durable tissues with minimal formaldehyde use. An embalming protocol involving phenoxyethanol was established, using concentrations of 7 and 1.5 Vol% of phenoxyethanol in the fixative and the conservation fluid, respectively. Visual, haptic, histological, and biomechanical properties and their perceived potential to positively influence student learning outcomes were compared to standard embalming techniques. The phenoxyethanol technique provides esthetic, durable, and odorless tissues. Bleaching is less pronounced compared to ethanol- or formaldehyde-based protocols. The tissues remain pliable following the phenoxyethanol-based embalming and can be used for biomechanical experiments to some extent. Phenoxyethanol-fixed tissues are well suited for undergraduate teaching with perceived positive learning outcomes and partly for postgraduate training. Phenoxyethanol tissues provide the option to obtain well-preserved histology samples, similar to those derived from formaldehyde. The provided protocol helps replace the use of phenol and formaldehyde for conservation purposes and minimizes the use of formaldehyde for the initial injection fixation. Phenoxyethanol-based embalming forms an effective alternative to standard embalming techniques for human cadavers. It is simple to use, allowing fixation procedures to be carried out in less sophisticated facilities with non-anatomy staff. 相似文献
975.
Biomechanical differences in double poling (DP) between sex and performance level were investigated in female and male cross-country skiers during a classical race (10/15 km). Skiers were divided into faster and slower on basis of race performance: females faster (n=20), females slower (n=20), males faster (n=20), and males slower (n=20). Based on video analysis while DP in a flat section of the track, joint and pole angles at pole plant (PP) and pole-off, cycle characteristics and the use and coordination pattern of heel-raise (raise of heels from the ground to have a higher body position at PP) were analysed. Faster females and males had 4.3% and 7.8% higher DP velocity than their slower counterparts (both P<0.001). Faster males had 6.5% longer cycles than slower males (P<0.001). Faster skiers stopped heel-raise later than slower skiers (females: 2.0±3.4% vs. ?1.0±3.5%, P<0.05; males: 3.9±2.4% vs. 0.8±3.2% of cycle time in relation to PP, P<0.001). At PP, faster skiers and male skiers had a smaller pole angle and greater ankle to hip and ankle to shoulder angle with respect to vertical, resulting in a more distinct forward body lean. However, the majority of the differences are likely due to higher DP velocity. 相似文献
976.
Christopher Mesagno Jacob Garvey Stephanie J. Tibbert Peter Gröpel 《Research quarterly for exercise and sport》2019,90(2):217-226
When athletes fail to perform at an expected level during an important moment, it is implied the athletes have experienced “choking“ (sudden decline in performance) under pressure.”. Researchers have reported that persistent left-hemispheric activation patterns occur when an athlete experiences considerable performance deteriorations under pressure. Researchers have also observed differences in brain activation patterns between left- and right-handed people on a variety of physical and cognitive tests, with the left-hemispheric activation more pronounced in right-handed participants. Purpose: The purpose of this study was to investigate whether athletes’ handedness may be linked to choking susceptibility (i.e., likelihood to experience performance decline under pressure). Method: Twenty right-handed and 13 left-handed experienced Australian football players completed 15 shot attempts, in both a low-pressure and a high-pressure condition. Both groups displayed equal state anxiety increases due to the pressure manipulation, indicating similar increases in anxiety in both handedness groups. Results: Differences were indicated in performance between the left- and right-handed groups during the high-pressure condition, with the left-handed group maintaining, and the right-handed participants declining, performance. Conclusion: Future electroencephalogram (EEG) research investigating this link may clarify the effect between handedness and choking. 相似文献
977.
While scholarly attention with respect to the social impacts of sports events has increased in recent years, there is still little research discussing the wide-ranging community-related impacts stemming particularly from major sports events. Local political leaders, as (elected) representatives of the community, are important stakeholders within this context and face the challenge of balancing diverse interests in the implementation of major sports events. The purpose of this study is to assess the importance politicians attribute to event impacts that create sustainable outcomes for residents living in a host city. Based on a content analysis, a list of general event impacts (outputs and legacies) produced by major sports events was created and subsequently discussed with scholars and experts in the field to classify the criteria as community relevant or not. A final number of 56 criteria (34 of which are considered community relevant) was then used in the assessment of the politicians’ (representing either the State of Tyrol or the City of Innsbruck) attitude towards these impacts. The findings of the study indicate that, though aware of community interests, politicians nevertheless prioritize economic and touristic benefits for the host city/region such as place marketing. Moreover, politicians seem to have a better understanding of tangible impacts (e.g. infrastructure), underestimating the important intangible impacts (e.g. voluntariness) closely related to community issues. Thus, the research in hand outlines the need to sensitize governments to community interests when planning and implementing major sports events. 相似文献
978.
André Brännström Ji-Guo Yu Per Jonsson Torbjörn Åkerfeldt Mats Stridsberg 《European Journal of Sport Science》2017,17(2):249-256
The present work investigated serum vitamin D (25(OH)D) status in relation to bone and muscle qualities and functions in 19 female soccer players (13–16 years) resident at northern latitude with very low sun exposure (~32–36?h/month) during winter season (late January to early March). Serum 25(OH)D, parathyroid hormone and bone turnover markers osteocalcin (OC) and beta carboxy-terminal collagen cross-links (β-Ctx), as well as body composition and muscle performance were examined. Hormones were tested using routine laboratory methods. Fat mass, lean mass, and bone mineral density in whole body, as well as femur and lumbar spine were evaluated with dual-energy X-ray absorptiometry. Muscle performance was assessed through isokinetic knee extension and flexion, countermovement jump, and sprint running. 25(OH)D was low (50.5?±? 12.8?nmol?l?1), whereas the values of bone turnover markers were markedly high (OC: 59.4?±? 18.6?µg?l?1; β-Ctx: 1075?±? 408?ng?l?1). All bone and muscle measurements were normal or above normal. 25(OH)D was not significantly correlated with most of the parameters of bone and muscle quality or function, except the knee extension time to peak torque (r ? =? ?0.50, p?=? .03). In conclusion, the level of vitamin D is markedly low in adolescent female soccer players during the winter in Sweden. However, vitamin D levels did not significantly correlate with measures of bone and muscle except a moderate correlation in time to peak torque in the knee extensors. The practical implication of low vitamin D levels in young growing female athletes remains unclear. 相似文献
979.
Tobias Wunsch Josef Kröll Thomas Stöggl Hermann Schwameder 《European Journal of Sport Science》2017,17(3):303-309
Research to enhance running performance has led to the design of a leaf spring-structured midsole shoe (LEAF). In treadmill running, it has been shown that LEAF led to an increased running economy and increased stride length (SL) through a horizontal foot shift during stance compared to a standard foam shoe (FOAM). The purpose of this study was to analyse whether (a) these findings can also be observed in overground running and (b) relations exist between spatio-temporal variables and running economy. Ten male long-distance heel-strike runners ran at their individual 2?mmol/l blood lactate speed with LEAF and FOAM in randomized order. Kinematic data were recorded with an inertial measurement unit synchronized with 2D video. Oxygen consumption was measured using an automated metabolic gas analysis system. Blood lactate was collected after each run. The strike pattern was unaffected by LEAF. SL was increased by 0.9?±?1.1?cm (95% CI 0.2 to 1.5; p?=?.040; dz?=?0.76), stride rate (SR) was reduced by ?0.4?±?0.3?strides/min (95% CI ?0.6 to ?0.1; p?=?.029; dz?=?0.82) and oxygen consumption tended to be reduced by 1% (?0.4?±?0.6?ml/min/kg; 95% CI ?0.8 to 0.0; p?=?.082; dz?=?0.62) when running with LEAF compared to FOAM. Changes in oxygen consumption in LEAF were correlated with SL (r?=?0.71; p?=?.022) and SR (r?=??0.68; p?=?.031). It can be concluded that LEAF has the potential to cause small changes in spatio-temporal variables during running. Runners increasing SL and decreasing SR in response to LEAF can achieve small improvements in running economy, which is beneficial in terms of performance. 相似文献
980.