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131.
Johnny Nilsson Sandor Csergö Lennart Gullstrand Per Tveit Per Egil Refsnes 《Journal of sports sciences》2013,31(11):939-945
The aim of this study was to examine work-time profiles, blood lactate concentrations and perceived exertion among Greco-Roman wrestlers in the 1998 World Championship. Forty-two senior wrestlers from nine nations were studied in 94 matches. Each match was recorded with a video camera (Panasonic AG 455, film rate: 25 Hz) and analysed for duration of work (wrestling) and rest (interrupt) periods. Blood lactate concentration was determined with an electrochemical device (Analox P-LM5) and a rating of perceived exertion scale (Borg) was used to estimate general exertion and exertion in the extremity and trunk muscles. The mean duration of the matches was 427 s (range 324-535 s), with mean durations of work and rest of 317 and 110 s, respectively. The mean periods of work and rest were 37.2 and 13.8 s, respectively. Mean blood lactate concentration was 14.8 mmol · l -1 (range 6.9-20.6). The difference in mean blood lactate concentration between the first- and final-round matches was not significant ( P > 0.05). Blood lactate concentration was significantly higher ( P ? 0.04) in matches of long duration than in those of short duration. The mean general rating of perceived exertion for all matches was 13.8 according to the scale used. Most of the wrestlers (53.3%) perceived exertion to be highest in the flexors of the forearm, followed by the deltoids (17.4%) and the biceps brachii muscles (12.0%). In addition to a relatively high rating of perceived exertion in the arm muscles, this indicates a high specific load on the flexor muscles of the forearm. 相似文献
132.
The spelling of many disyllabic English word endings holds cues to their grammatical category, beyond obvious inflectional endings such as -ing for verbs. For example, some letter sequences are clearly associated with nouns (e.g., -oon) and others with verbs (e.g., -erge). This study extended recent research by Arciuli and Cupples (2006), and confirmed that skilled adult readers are sensitive to these orthographic cues. It was found that adults were more likely to treat pseudowords as nouns when they had noun-like endings than verb-like or control endings, and more likely to treat pseudowords as verbs when they had verb-like than noun-like endings. This sensitivity held across three tasks (sentence construction, sentence judgement, and pseudoword judgement), which required increasingly explicit awareness of the way that cues could allow grammatical categorisation. In some tasks sensitivity to verb-like endings was related to reading ability, although not to spelling ability or grammatical awareness. Implications for our understanding of language processing are discussed. 相似文献
133.
In the golf instructional literature, the putting stroke is typically given higher priority than green reading and aiming. The main purpose of this study was to assess the importance of the putting stroke for direction consistency in golf putting. Kinematic stroke parameters were recorded from 71 elite golf players (mean handicap = 1.8, s = 4.2) on 1301 putts from about 4 m. Of the different factors deciding stroke direction consistency, face angle was found to be the most important (80%), followed by putter path (17%) and impact point (3%). This suggests that improvements in consistency of putter path and impact point will have very little effect on overall putting direction consistency and should not be prioritized in the training of elite players. In addition, mean stroke direction variability for an elite player (European Tour) was found to be 0.39 degrees, which is good enough to hole about 95% of all 4-m putts. In practice, however, top professionals in tournaments only hole about 17% of 4-m putts. We conclude that the putting stroke of elite golfers has a relatively minor influence on direction consistency. 相似文献
134.
Angela Lo Monaco Elisabetta Mattei Claudia Pelosi Marco Santancini 《Journal of Cultural Heritage》2013,14(6):537-543
The focus of this work is the wood polychrome model of the church of S. Maria della Consolazione in Todi, an artefact whose author and historical events are not completely known except a general reference to the construction period of the church (1508–1607 AD). In this study, original and additional materials were examined in order to provide a deeper understanding of the painting and assembly techniques, and a greater awareness of how well preserved the object is, as well as an analysis of previous preservation and conservation interventions. The samples from the painted surfaces were examined by means of micro-Raman spectroscopy, fourier transform infrared (FTIR) spectrometry and internal microstratigraphic analysis. Thin sections of the wood samples were examined under an optical transmission light microscope in order to identify the botanical species. The results shown in this paper suggest the possibility that the original painted layers are made of calcium carbonate white, red ochre and indigo and they were applied by protein binder without any ground layer. Some non-original pigments were found on the model surface like Prussian blue and chrome yellow. Concerning wood components, poplar was characterized both in the original and non-original parts of the model whereas pine species were detected only in the restoration elements. 相似文献
135.
Identification of a nonlinear dynamic biological model using the dominant parameter selection method
Ilya Ioslovich Marco Ivan Ramirez-Sosa Moran 《Journal of The Franklin Institute》2010,347(6):1001-1014
The identification of nonlinear models sometimes encounters problems because of the limited amount of available measurements in combination with a large number of uncertain model parameters to be identified. E.g., the determination of the chemical composition of a lettuce crop is a rather expensive procedure; thus the number of experimental measurements is limited. As a result, the number of parameters of the dynamic model that can be successively identified is also limited, and the subset of the parameters to be identified must be chosen in a reasonable way.Parameter estimation for an extended nonlinear three-state model for lettuce growth in greenhouses is presented in this paper. The varying structural nitrogen concentration and water contents are the new elements included in the model. The dominant parameter selection (DPS) method was used to select a suitable set of identifiable parameters. The resulting calibrated model predicts quite well the experimental data which also include observations with severe nitrogen stress. 相似文献
136.
137.
Orloff ND Dennis JR Cecchini M Schonbrun E Rocas E Wang Y Novotny D Simmonds RW Moreland J Takeuchi I Booth JC 《Biomicrofluidics》2011,5(4):44107-441079
We present a 91 MHz surface acoustic wave resonator with integrated microfluidics that includes a flow focus, an expansion region, and a binning region in order to manipulate particle trajectories. We demonstrate the ability to change the position of the acoustic nodes by varying the electronic phase of one of the transducers relative to the other in a pseudo-static manner. The measurements were performed at room temperature with 3 μm diameter latex beads dispersed in a water-based solution. We demonstrate the dependence of nodal position on pseudo-static phase and show simultaneous control of 9 bead streams with spatial control of −0.058 μm/deg ± 0.001 μm/deg. As a consequence of changing the position of bead streams perpendicular to their flow direction, we also show that the integrated acoustic-microfluidic device can be used to change the trajectory of a bead stream towards a selected bin with an angular control of 0.008 deg/deg ± 0.000(2) deg/deg. 相似文献
138.
Marco Cucculelli 《Research Policy》2012,41(5):808-821
This study contributes to the recent empirical literature on the innovation-firm performance relationship by investigating the effect of product introduction on firm growth in a sample of Italian firms from 2000 to 2006. We adopted a novel approach that exploits the interpretative content of the tenure of the last product introduced (i.e., the number of years since its first introduction) as an additional variable into the explanatory scheme of firm sales growth rate. This variable aims to capture peculiar characteristics of new goods, such as their novelty and complexity. The estimated results confirmed the relevance of this model specification and helps in understanding the reason why previous studies have failed to find a statistically robust relationship between product innovation and growth. Moreover, we found the following: first, the release of a new product enhances growth opportunity among multiproduct firms; second, product development promotes the growth of firms belonging to sectors with stronger commitment to research and development; and third, new product development enhances firm growth substantially in those sectors that absorb externally originated patents. 相似文献
139.
Educational Studies in Mathematics - Visuospatial representations of numbers and their relationships are widely used in mathematics education. These include drawn images, models constructed with... 相似文献
140.