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21.
Cadore E Lhullier F Brentano M Silva E Ambrosini M Spinelli R Silva R Kruel L 《Journal of sports sciences》2008,26(10):1067-1072
The aim of present study was to examine the relationships between serum and salivary values of free testosterone, dehydroepiandrosterone, and cortisol before and after a session of resistance exercise. Twenty-eight healthy men (mean age 40 years, s = 4) participated in the present study. Serum and salivary samples were collected at rest and after a multiple-sets resistance exercise protocol, of approximately 25 minutes duration. Concentrations of free testosterone, dehydroepiandrosterone, and cortisol were measured using radioimmunoassay kits. No significant correlation was observed between serum free testosterone and salivary testosterone (r = 0.22 to 0.26, P > 0.05). Serum cortisol was significantly correlated with salivary cortisol before (r = 0.52, P = 0.005) and after (r = 0.62, P = 0.001) the exercise protocol. Serum and salivary concentrations of dehydroepiandrosterone were significantly correlated before (r = 0.68, P < 0.001) and after (r = 0.7, P < 0.001) exercise. The results of the present study suggest that even under exercise conditions, the salivary values of cortisol and dehydroepiandrosterone can reflect the behaviour of these hormones in blood. However, further studies are necessary to verify if salivary testosterone reflects the behaviour of serum free testosterone during resistance exercise. 相似文献
22.
E.B. Ogle Stuart McFadyen Shirley Serafini Michel Andrieu 《Communication Booknotes Quarterly》2013,44(9)
E.B. Ogle, Long Distance Please: The Story of the TransCanada Telephone System (Toronto: Collins, 1979—$14.95) Stuart McFadyen, et al., Canadian Broadcasting: Market Structure and Economic Performance (Montreal: Institute for Research on Public Policy/available in U.S. from Renouf, Old Post Rd., Brookfield, Vt. 05036—$15.95, paper) The Information Revolution and its Implications for Canada by Shirley Serafini and Michel Andrieu (November 1980, 113 pp. —$4.95, paper) Telecommunications and Canada: Consultative Committee on the Implications of Telecommunications for Canadian Sovereignty (March 1979, 98 pp.—$6.00, paper) The 1980s: A Decade of Diversity–Broadcasting, Satellites, and Pay-TV (.July 1980, 94 pp.—$3.95, paper) Attitudes of Canadians Toward Advertising on Television (1978, 55 pp.—$2.00, paper) 相似文献
23.
Matthias Bender Sebastian Michel Gerhard Weikum und Christian Zimmer 《Informatik - Forschung und Entwicklung》2005,20(3):152-166
Zusammenfassung In diesem Artikel wird MINERVA pr?sentiert, eine prototypische Implementierung einer verteilten Suchmaschine basierend auf
einer Peer-to-Peer (P2P)-Architektur. MINERVA setzt auf die in der P2P-Welt verbreitete Technik verteilter Hash-Tabellen auf
und benutzt diese zum Aufbau eines verteilten Verzeichnisses. Peers in unserem Ansatz entsprechen v?llig autonomen Benutzern mit ihren lokalen Suchm"oglichkeiten, die bereit sind, ihr lokales
Wissen und ihre lokalen Suchm?glichkeiten im Rahmen einer Kollaboration zur Verfügung zu stellen. Wir formalisieren unsere
Systemarchitektur und beschreiben das zentrale Problem einer effizienten Suche nach vielversprechenden Peers für eine konkrete
Anfrage innerhalb des Verbundes. Wir greifen dabei auf existierende Methoden zurück and passen diese an unseren Systemkontext
an. Wir pr?sentieren Experimente auf realen Daten, die verschiedene dieser Ans?tze vergleichen. Diese Experimente zeigen,
dass die Qualit?t der Ans?tze variiert und untermauern damit die Wichtigkeit und den Einfluss einer leistungsstarken Methode
zur Auswahl guter Datenbanken. Unsere Experimente deuten an, dass eine geringe Anzahl sorgf?ltig ausgew?hlter Datenbanken
typischerweise bereits einen Gro?teil aller relevanten Ergebnisse des Gesamtsystems liefert.
This paper presents the MINERVA project that protoypes a distributed search engine based on P2P techniques. MINERVA is layered on top of a Chord-style overlay network and uses a powerful crawling, indexing, and search engine on every autonomous peer. We formalize our system model and identify the problem of efficiently selecting promising peers for a query as a pivotal issue. We revisit existing approaches to the database selection problem and adapt them to our system environment. Measurements are performed to compare different selection strategies using real-world data. The experiments show significant performance differences between the strategies and prove the importance of a judicious peer selection strategy. The experiments also present first evidence that a small number of carefully selected peers already provide the vast majority of all relevant results.
CR Subject Classification H.4,H.3.3,H3.4 相似文献
24.
A study was conducted to assess the validity of the Global Physical Activity Questionnaire (GPAQ) for measuring sedentary behaviour (SB) in the Chilean adult population. About 217 adults (93/124 male/female, 43.8 ± 15.75 years) who were randomly selected during National Health Survey 2009–2010 completed the protocol. The participants wore an ActiGraph GT3X (AG) for 7 consecutive days and then completed the GPAQ (single-item question for measuring time spent sitting in a usual day). Validity was examined using Spearman’s correlation, mean bias and limits of agreement (LoA), with AG (vertical axis <100 counts · min?1) as the reference standard for estimates of SB in bouts of 1 (AG1), 5 (AG5) and 10 (AG10) min. Agreement between the GPAQ and AG for classifying data into quartiles and tertiles was assessed with kappa method. The GPAQ showed fair correlation with AG1, AG5 and AG10 (range = 0.23–0.26), with large mean biases (range = ?293.9, ?76.12 min · day?1). Agreement between the GPAQ and AG1, AG5 and AG10 was poor for categorising time spent in SB into tertiles and quartiles. The single question from the GPAQ has shown fair validity for measuring SB and poor ability for correctly classifying individuals into tertiles or quartiles of SB in a Chilean population. 相似文献
25.
Nicolas Milazzo Damian Farrow Alexis Ruffault Jean F. Fournier 《Journal of sports sciences》2016,34(16):1547-1556
This study examined the contribution of situational probability information to the perceptual and cognitive processes underlying decision-making behaviour during in situ Karate performance. Experts and novices were required to make decisions about various attacks in different fight scenarios. The order in which the fight situations were presented was modified in order to provide advanced probability information and identify whether fighters were able to use the latter information to make better decisions. Specifically, one of the attacks was repeated every four actions. Results revealed that experts were more accurate and faster than their less skilled counterparts to block and counterattack the opponent. The experts picked up the occurrence of the attack pattern after the fifth repetition whereas novices did not. This enabled experts to improve decision time and decision accuracy. Findings suggest that such superiority could stem from the perceptual and cognitive skills possessed by the experts, thus giving them the opportunity to recognise a situation more easily. This was reinforced by gaze behaviour which demonstrated that experts used a more efficient search strategy involving fewer fixations of longer duration on a lesser number of areas relative to the novices. Moreover, experts generated more refined karate-specific knowledge structures compared with the novices. 相似文献
26.
27.
Nicolas Delorme 《Mass Communication and Society》2014,17(1):121-147
In previous literature, there is an important heterogeneity in how to proceed to determine whether media coverage of the Summer Olympics in relation to athletes' sex is equitable. Therefore, the aims of this study are to determine the most appropriate standards for this comparison and to use them to assess whether there are biases in the journalistic coverage of the Summer Games, using data from previous studies (n = 18). Results show that media coverage is far from being detrimental to women: They are either equitably represented (28.79%) or significantly overrepresented (46.97%). Indeed, all modalities combined, women are only underrepresented in 22.24% of cases. In most cases, these results significantly differ from those of previous research and stress the importance of and the need to take methodological precautions in this type of study. 相似文献
28.
The debate about whether the arts should be supported or not is far from new, and most governments support the arts in one
way or the other. The literature considers several arguments in favor of such interventions. Public education may seem to
be an action which could, in the long run, lead to possible reductions of subsidies. Surveys show that those who have been
exposed to the arts when young participate more when adult. However, the “non-market” transmission from parents to children
generates an external effect, which has to be taken into account to reach first-best situations. We construct an overlapping
generations model in which young consumers are exposed to both public education toward the arts and to non-altruistic transmission
of such a taste from their parents. We show that the first-best can be reached only if there is both public cultural education
and subsidization of arts consumption. Therefore, education cannot be considered as a substitute for subsidies to arts consumption.
However, as is often the case in European countries, government intervention is usually below the first-best level. Using
a model calibrated on French data, we show that it is then preferable to subsidize education, while consumption, especially
of the older generations, should be taxed rather than subsidized.
相似文献
Luc ChamparnaudEmail: |
29.
30.
Michel Pagnier 《Higher Education Quarterly》1973,27(3):323-345