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101.
Doping in sports is commonplace. The prevention of harm to the athlete, the guarantee of fair play, and a level playing field for all competitors are the basis of the current anti-doping strategies. As healthcare systems are forced to allocate increasing resources to prevent and treat the prevailing pathologies worldwide, funding for anti-doping campaigns will necessarily be restricted. Ideally, additional resources should be devoted to increasing the number of athletes tested, the panels of tests used, and the frequency of out-of-competition controls. Since doping prevention cannot be considered a priority for most healthcare systems, such an approach is unaffordable and an alternative framework should be devised, focused primarily on harm reduction rather than fair play. The identification of abnormal deviations from reference values, regardless of pathological or artificial causes, would allow the athlete to be followed and tested using conventional laboratory tests, which are affordable to governments and healthcare systems and available to clinical laboratories. Although this strategy would not detect cheating, it would safeguard athletes' health. 相似文献
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103.
Giuseppe Grassi Author Vitae 《Journal of The Franklin Institute》2010,347(2):438-451
Projective synchronization is a type of chaos synchronization where the response system states are scaled replicas of the drive system states. This paper deals with the propagation of projective synchronization in a series connection of N chaotic discrete-time drive systems and N response systems. By exploiting an observer-based approach, the paper demonstrates that dead-beat projective synchronization (i.e., exact synchronization in finite time for any scaling factor) is achieved between the nth drive and nth response systems. In particular, it is shown that projective synchronization starts from the innermost (Nth) drive-response system pair and propagates toward the outermost (first) drive-response system pair. Only a single scalar synchronizing signal connects the cascaded drive and response systems. Finally, an example illustrates the propagation of different types of chaos synchronization in a series connection consisting of a Gingerbreadman map, a third order hyperchaotic Henon map and a Lozi map. 相似文献
104.
Giuseppe Gibertini Donato Grassi Carlo Macchi Giuseppe De Bortoli 《Sports Engineering》2010,12(3):155-161
The present paper describes the activity carried out to investigate the aerodynamic effects of cycling shoes for time trial
competitions. This subject has not been widely studied but can be important for an accurate aerodynamic optimisation of a
time trial cyclist. The study was carried out by means of wind tunnel testing: an appropriate test setup and an appropriate
test procedure (based on “effective angle of attack approach”) were developed in order to produce realistic test conditions.
The developed testing procedure was applied to two different shoe models, differently fastened. Furthermore, an important
point was the investigation of the overshoe effect. The results showed that the power required to overcome the shoe’s drag
is almost a tenth of the total power and that differences between the shoes can affect the cyclist’s performance. 相似文献
105.
Swelling damage in clay-rich sandstones used in the church of San Mateo in Tarifa (Spain) 总被引：1，自引：0，他引：1
Eduardo Sebastin Giuseppe Cultrone David Benavente Lucia Linares Fernandez Kerstin Elert Carlos Rodriguez-Navarro 《Journal of Cultural Heritage》2008,9(1):66-76
This study shows that the sandstone used in the construction of the Church of San Mateo in Tarifa (Cádiz, Spain) is highly sensitive to processes of decay because of a combination of factors that are intrinsic and extrinsic to the material. The mineralogy, texture and porous system of the sandstone and the proximity of the church to the sea all play a part in these processes. X-ray diffraction reveals that there are interstratified chlorite/smectite clays among the minerals that make up the rock. These mixed layer clays have been shown to undergo hydric expansion. This phenomenon may be accompanied and augmented by the presence of NaCl which acts as an electrolyte in osmotic swelling processes. Two varieties of sandstone were used in the construction of the church, namely grey sandstone and brown sandstone. The latter is more porous and undergoes greater hydric expansion, showing a higher degree of deterioration. Ultrasound analysis has demonstrated that both varieties are anisotropic because they contain bedding planes and are affected by the preferred orientation of the phyllosilicates in the rock. The anisotropic nature of these stones was confirmed by capillary suction tests. The capillary front reaches a relatively low height which means that when water is absorbed, the anisotropic textural properties combined with the presence of chlorite–smectite mixed layers in the sandstone result in mechanical (shear) stress between the first few centimetres of the wet stone and the dry area behind. The latter effect favours the development of flakes, so causing the decay of the ornamental stone and the church façade. 相似文献
106.
Giuseppe Maria Russo Patricia Amlia Tomei Antonio Braga Jos Linhares Andr Moreira Santos 《Performance Improvement》2013,52(7):13-21
Alignment between management strategies, policies, and practices with organizational cultures holds great potential to meet the challenges of retaining professionals and maintaining their commitment. In this article, authors consider that when it is aligned with company strategy, compensation acts as an incentive for developing common visions within organizational culture. 相似文献
107.
Giuseppe Lippi Paola Avanzini Roberta Musa Franca Sandei Rosalia Aloe Gianfranco Cervellin 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(1):64-69
Background:
In vitro hemolysis can be induced by several biological and technical sources, and may be worsened by forced aspiration of blood in vacuum tubes. This study was aimed to compare the probability of hemolysis by drawing blood with a commercial evacuated blood collection tube, and S-Monovette used either in the “vacuum” or “aspiration” mode.Materials and methods:
The study population consisted in 20 healthy volunteers. A sample was drawn into 4.0 mL BD Vacutainer serum tube from a vein of one upper arm. Two other samples were drawn with a second venipuncture from a vein of the opposite arm, into 4.0 mL S-Monovette serum tubes, by both vacuum an aspiration modes. After separation, serum potassium, lactate dehydrogenase (LD) and hemolysis index (HI) were tested on Beckman Coulter DxC.Results:
In no case the HI exceed the limit of significant hemolysis. As compared with BD Vacutainer, no significant differences were observed for potassium and LD using S-Monovette with vacuum method. Significant increased values of both parameters were however found in serum collected into BD Vacutainer and S-Monovette by vacuum mode, compared to serum drawn by S-Monovette in aspiration mode. The mean potassium bias was 2.2% versus BD Vacutainer and 2.4% versus S-Monovette in vacuum mode, that of LD was 2.7% versus BD Vacutainer and 2.1% versus S-Monovette in vacuum mode. None of these variations exceeded the allowable total error.Conclusions:
Although no significant macro-hemolysis was observed with any collection system, the less chance of producing micro-hemolysis by S-Monovette in aspiration mode suggest that this device may be used when a difficult venipuncture combined with the vacuum may increase the probability of spurious hemolysis. 相似文献108.
Marco Beato Franco M. Impellizzeri Giuseppe Coratella Federico Schena 《Journal of sports sciences》2016,34(24):2185-2188
ABSTRACTThere is a strong relationship between low physical activity level and cardiovascular diseases (CVD). The popularity of football may be used to promote physical activity and previous evidence has shown it is effective to decrease the risk of CVD. However, the energy expenditure (EE) of recreational football is not well known but it is crucial to develop preventive health programmes.Fifteen sedentary middle-aged male participants were involved (mean ± SDs; age 43.9 ± 3.1 years, weight 83.0 ± 13.6 kg, height 174.9 ± 6.8 cm). EE was estimated from the heart rate (HR)-VO2 relation during 1-h 5-a-side matches (futsal). Participants covered 3412 ± 381 m in 52 ± 2 min, at an average HR of 85 ± 2% of maximum HR. Estimated EE during a recreational futsal match was 634 ± 92 kcal. One futsal recreational match corresponds to about 50% of American College of Sport Medicine recommended physical activity quantity per week. Based on this estimation: once, twice and 3 sessions per week are equivalent to 50% (634 kcal), 100% (1268 kcal) and 150% (1902 kcal), respectively, of EE suggested in international guidelines. This EE estimation may have important implications for designing recreational football training protocols in health programmes and dose response studies. 相似文献
109.
Michelle Malizia Catalano Porcia Vaughn Joshua Been 《Medical reference services quarterly》2017,36(4):415-422
Data play a crucial role in health research, education, and patient care. Initiatives such as Big Data to Knowledge (BD2K) and Precision Medicine point to the increasing focus and value of data use and reuse. As the universe of data continues to grow exponentially, health education needs to provide students with practical hands-on learning sessions that illustrate the multitude of uses for data and statistics. Giving students early exposure to data reuse provides a solid background for the more complex data they may gather later in their education. This column describes how librarians at a general academic library used data dashboards and Tableau in two library sessions to provide students with hands-on experience in data visualization and its role in decision-making. 相似文献
110.
Theresa Catalano Jill Fox Saloshna Vandeyar 《Journal of Language, Identity & Education》2016,15(3):137-150
Much research is available that details student experiences of immigration and adaptation to receiving countries and schools, but few studies analyze the metaphors used by immigrant students (IS) when talking about the immigration experience, or offer a comparative lens through which to view identity negotiation in two very different contexts. The present paper aims to address these gaps by conducting a comparative linguistic analysis of 20 interviews conducted with IS at universities in South Africa and the United States in order to gain a greater understanding of immigration and the types of identity negotiation processes learners undergo in these very different countries. Findings reveal interesting similarities between metaphorical conceptions of immigration across different cultural contexts and a remarkable resilience in the use of adaptation strategies and identity development that leads to salient pedagogical implications for teachers of higher education who face increasingly international classrooms. 相似文献