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161.
Cassidy R. Sugimoto Vincent Larivière Chaoqun Ni Blaise Cronin 《Journal of Informetrics》2013,7(4):897-906
There are many indicators of journal quality and prestige. Although acceptance rates are discussed anecdotally, there has been little systematic exploration of the relationship between acceptance rates and other journal measures. This study examines the variability of acceptance rates for a set of 5094 journals in five disciplines and the relationship between acceptance rates and JCR measures for 1301 journals. The results show statistically significant differences in acceptance rates by discipline, country affiliation of the editor, and number of reviewers per article. Negative correlations are found between acceptance rates and citation-based indicators. Positive correlations are found with journal age. These relationships are most pronounced in the most selective journals and vary by discipline. Open access journals were found to have statistically significantly higher acceptance rates than non-open access journals. Implications in light of changes in the scholarly communication system are discussed. 相似文献
162.
ABSTRACTOur understanding of spelling development has largely been gleaned from analysis of children’s accuracy at spelling words under varying conditions and the nature of their errors. Here, we consider whether handwriting durations can inform us about the time course with which children use morphological information to produce accurate spellings of root morphemes. Six- to 7-year-old (n = 23) and 8- to 11-year-old (n = 25) children produced 28 target spellings in a spelling-to-dictation task. Target words were matched quadruplets of base, control, inflected, and derived words beginning with the same letters (e.g., rock, rocket, rocking, rocky). Both groups of children showed evidence of morphological processing as they prepared their spelling; writing onset latencies were shorter for two-morpheme words than control words. The findings are consistent with statistical learning theories of spelling development and theories of lexical quality that include a role of morphology. 相似文献
163.
Agnès Lattuati-Derieux Céline Egasse Sylvie Thao-Heu Nathalie Balcar Gilles Barabant Bertrand Lavédrine 《Journal of Cultural Heritage》2013,14(3):238-247
In recent years, plastics are designated as a source of indoor pollution and particular attention has thus been devoted to the identification of emitting low molecular weight compounds. Headspace-solid phase microextraction-gas chromatography coupled with mass spectrometry (HS-SPME-GC/MS) has been already successfully applied for screening emissions from synthetic materials. This analytical tool being also non-invasive, it has been already successfully applied in the field of cultural heritage science for the identification of volatile organic compounds (VOCs) emitted from various museum objects made of natural materials. In this research, we aimed at assessing the use of HS-SPME-GC/MS as an in situ non-invasive analytical tool for a better knowledge of the volatile organic compounds emitted by plastics in collections. The possibility of characterizing plastics based on their emission signatures was also evaluated. Twelve new standard plastic samples, belonging to seven main polymer families widely present in museum collections as well as three naturally aged museum objects, were investigated. In this paper, we provide a survey of the VOCs emitted, and the use of HS-SPME-GC/MS for identifying volatile marker compounds, degradation products, additives, and monomer residues of the plastic synthesis is evaluated. More than 200 different VOCs were identified from the new standard samples. Two categories of VOCs were distinguished: “non-specific” and “specific” ones. We showed that based on the “specific” VOCs, it was possible to identify the nature of the polymeric matrix itself or at least to unambiguously distinguish a plastic by family. Emissions from the museum objects were then characterised, and main volatile degradation compounds considered as degradation markers of the natural deterioration of polymeric matrices, were identified. This identification procedure could be further exploited for the characterization of VOCs emitted by objects made of multiple synthetic polymers. Complementary to other techniques, this analytical tool is an interesting way to assess the risk for the objects stored in the vicinity of emitting plastics. 相似文献
164.
165.
Patrice Rougier Nicolas Genthon Thibault Gallois-Montbrun Steve Brugière Eric Bouvat 《Research quarterly for exercise and sport》2013,84(4):702-709
To highlight the capacity of one- and two-legged standing protocols when assessing postural behavior induced by a rigid ankle orthosis, 14 healthy individuals stood upright barefoot and wore either an elastic stocking on the preferred leg or a rigid orthosis with or without additional taping in one- or two-legged (TL) conditions. Traditional center-of-pressure (CP) measures were evaluated for the total two-feet resultant CP and under the feet (plantar CP). Focusing on the plantar CP displacements under the leg fitted with the various orthoses demonstrated particular postural behaviors for traditional parameters with main effects along the mediolateral axis. Only the TL protocol showed the limiting effects of the rigid shells on the inversion-eversion movements in healthy individuals. 相似文献
166.
Chantal Bard Michelle Fleury Lise Carrière Madeleine Hallé 《Research quarterly for exercise and sport》2013,84(2):267-273
Abstract This study was designed to investigate the visual search patterns of gymnastics judges. The subjects were four national judges (experienced) and three local judges (novice). Three dependent variables were measured: the number and the location of ocular fixations during the evaluation of a gymnast's performance, and the number of errors made by the judges. Ocular fixations were studied by the corneal reflection technique with a NAC Eye-Movement Recorder. There was no statistical difference in the number of fixations for both groups of judges. However, the expert judges had 27% less fixations than the novice judges. A statistical difference was found between expert judges and novice judges for the location of fixations; experts had more fixations on the upper part of the gymnast's body, while novices concentrated their attention on the legs. The type of routine significantly affected the number of fixations; more fixations were found for optional routines. There was no statistical difference in the number of judgment errors made by the two groups of judges. However, novice judges detected only half the gymnast's errors detected by the expert judges. 相似文献
167.
Emiliano Cè Eloisa Limonta Martina A. Maggioni Susanna Rampichini Arsenio Veicsteinas 《Journal of sports sciences》2013,31(8):856-866
Abstract The study aimed to assess the role of deep and superficial massage and passive stretching recovery on blood lactate concentration ([La?]) kinetics after a fatiguing exercise compared to active and passive recovery. Nine participants (age 23 ± 1 years; stature 1.76 ± 0.02 m; body mass 74 ± 4 kg) performed on five occasions an 8-min fatiguing exercise at 90% of maximum oxygen uptake, followed by five different 10-min interventions in random order: passive and active recovery, deep and superficial massage and stretching. Interventions were followed by 1 hour of recovery. Throughout each session, maximum voluntary contraction (MVC) of the knee extensor muscles, [La?], cardiorespiratory and metabolic variables were determined. Electromyographic signal (EMG) from the quadriceps muscles was also recorded. At the end of the fatiguing exercise, [La?], MVC, EMG amplitude, and metabolic and cardiorespiratory parameters were similar among conditions. During intervention administration, [La?] was lower and metabolic and cardiorespiratory parameters were higher in active recovery compared to the other modalities (P < 0.05). Stretching and deep and superficial massage did not alter [La?] kinetics compared to passive recovery. These findings indicate that the pressure exerted during massage administration and stretching manoeuvres did not play a significant role on post-exercise blood La? levels. 相似文献
168.
Anthony M. J. Sanchez Olivier Galbès Frédérique Fabre-Guery Luc Thomas Aymeric Douillard Guillaume Py 《Journal of sports sciences》2013,31(14):1510-1519
Abstract The aim of the study is the modelling of training responses with a variable dose-response model in a sport discipline that requires highly complex coordination. We propose a method to optimise the training programme plan using the potential maximal performance gain associated with overload and tapering periods. Data from five female elite gymnasts were collected over a 3-month training period. The relationship between training amounts and performance was then assessed with a non-linear model. The optimal magnitude of training load reduction and its duration were investigated with and without an overload period using simulation procedures based on individual responses to training. The correlation between actual and modelled performances was significant (R 2 = 0.81 ± 0.02, P < 0.01). The standard error was 2.7%. Simulations revealed that taper preceded by an overload period allows a higher performance to be achieved compared to an absence of overload period (106.3 ± 0.3% vs. 105.1 ± 0.3%). With respect to the pre-taper load, the model predicts that optimal load reductions during taper were 48.4 ± 0.7% and 42.5 ± 1.0% for overloading and non-overloading strategies, respectively. Moreover, optimal durations of the taper period were 34 ± 0.5 days and 22 ± 0.5 days for overloading and non-overloading strategies, respectively. In conclusion, the study showed that the variable dose-response model describes precisely the training response in gymnasts. 相似文献
169.
Abstract The mechanical responses (i.e. external contact forces and external power) of 25 elite rowers to a race-pace rowing protocol were investigated on the traditional fixed stretcher mechanism and the more recently introduced free-floating stretcher mechanism rowing ergometers. Using a Rowperfect rowing ergometer for both conditions, external contact forces at the handle, stretcher and sliding seat, as well as the displacements of the handle and stretcher, were recorded. The external power was calculated as the product of the force and velocity data from both the handle and stretcher. Significant differences (P < 0.05) between the two conditions for each mechanical parameter were observed. The fixed condition showed larger maximum values for forces and external power and average power throughout the rowing cycle. Moreover, rowing with the fixed mechanism generated higher inertial forces during the transition between the propulsion and recovery phases, especially at the catch of the cycle. The results suggest that: (i) muscular coordination may differ according to the stretcher mechanism used, which could have an impact on the physiological adaptations of muscles; and (ii) the free-floating mechanism may induce lower catch and maximum values for net joint forces and net joint moments that could decrease the risk of injury. 相似文献
170.
Fabio Esposito Emiliano Cè Susanna Rampichini Arsenio Veicsteinas 《Journal of sports sciences》2013,31(12):1347-1357
Abstract The aim of this study was to assess the effects of acute passive stretching on the electrical and mechanical response of a previously fatigued muscle. Eleven participants underwent maximal tetanic stimulations (50 Hz) of the medial gastrocnemius, before and after a fatiguing protocol and after a bout of passive stretching of the fatigued muscle. During contraction, surface electromyography (EMG), mechanomyography (MMG), and force were recorded. The following parameters were calculated: (1) the EMG root mean square (RMS), mean frequency, and fibre conduction velocity; (2) MMG peak-to-peak and RMS; (3) the peak force, contraction time, half-relaxation time, peak rate of force development (dF/dt) and its acceleration (d2 F/dt 2). Fatigue reduced peak force by 18% (P < 0.05) and affected the other force, EMG, and MMG parameters. After stretching: (1) all EMG parameters recovered to pre-fatigue values; (2) MMG peak-to-peak remained depressed, while RMS recovered to pre-fatigue values; (3) the peak force, peak rate of force development and its acceleration were further reduced by 22, 18, and 51%, respectively, and half-relaxation time by 40% (P < 0.05). In conclusion, acute passive stretching, when applied to a previously fatigued muscle, further depresses the maximum force-generating capacity. Although stretching does not alter the electrical parameters of the fatigued muscle, it does affect the mechanical behaviour of the muscle–tendon unit. 相似文献