Open Science Journal (OSJ)
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Maximal oxygen uptake of male professional soccer players, 2012-2015, at the end of four preseasons training
Get PDFPurpose: We hypothesized that the aerobic capacity of soccer players was well developed and maintained during the competitive season and that a short rest period in the off-season would not be sufficient to significantly affect V̇O2max in these players. Methods: A total of 211 soccer athletes (age range, 17-34 years) being 71 professional juniors and 113 professional adults were compared with a control group of 27 non-professionals soccer players. All players performed cardiopulmonary exercise testing on a treadmill.Results: The results showed that a large number of soccer players had V̇O2max levels incompatible with the status of professional athletes in this sport. The results between the players were: The player’s juniors presented average V̇O2max (56.2 mL.min-1.kg-1) significantly higher (P < 0.05) of that the professional players (53.3 mL.min-1.kg-1) and controls (amateur, 50.4 mL.min-1.kg-1). However, a large number of the adult (67%) and juniors (42%) professionals players presented values of V̇O2max near to the values covered for the control group.Conclusions: The study verified a great number of soccer players, considered of the elite, with values below that it is recommended for players of this competitive level. It seems that preseason training was not enough to achieve compatible V̇O2max levels for most players
Sentinel-1 data to support monitoring deforestation in tropical humid forests
Get PDFIn recent years, methodologies for deforestation detection that use satellite data have been developed, primarily using optical data, which cannot detect deforestation in the presence of clouds. In this paper, we discuss a methodology developed to detect deforestation using Sentinel-1 data and that aims to complement typical early warning system based on optical satellite images such as one the Peruvian Government employs. The methodology was applied in three pilot areas in the tropical humid forest of Peru. Sentinel-1 data were acquired in Interferometric Wide Swath (IW) mode and VH polarization. We use a Gamma-Map filter to reduce the speckle noise, and the average of 3 chrono-sequentially continuous images to reduce the multi-temporal variation of the forest backscattering. This produced 6 time series for each pilot area. For the detection of deforestation, we used an algorithm based on the difference and ratio between the images before and after deforestation. The accuracy assessment revealed a user’s accuracy greater than 95%. We also made a multitemporal comparison between our results and the early warning tropical forest loss alerts that use only Landsat data, which showed that until the end of the study period 33.26% of the deforestation we detected was not detected by the early warning alerts that use Landsat data
Screening of refractive errors and ocular disorders of professional soccer players
No full textTo improve their performance, many athletes already invest a significant amount of time and effort in training camps, personal trainers, and equipment, while neglecting to invest in their vision. However, improving visual performance can help improve overall performance in a way that other training regiments cannot. Even for athletes without vision problems, improving visual performance - such as increasing dynamic visual acuity, decreasing reaction times, and improving eye-hand coordination - is an integral component of improving overall performance. To verify if the changes found in soccer players exceeded the 40% found in the literature. The athletes were all submitted to visual acuity (VA) tests without correction using the Snellen eye chart and the noncontact intraocular pressure (IOP) by means of a computerized tonometer. They also underwent a self-refraction examination through a self-refractor. Among the 54 athletes that presented to the screening (108 eyes) 93/108 (86%) had refractive errors in one or both eyes. In 108 eyes there was 50 (46%) hyperopic eye with astigmatism; 19/108 (18%) of myopic astigmatism, 15/108 (14%) with myopia, 6/108 (6%) with hypermetropy and 15/108 (14%) were emmetropes. The prevalence of refractive errors was hyperopic astigmatism followed by myopic astigmatism (50 vs 19 cases). The left eye was the one that presented more hyperopic and myopic astigmatism in relation to the right eye, 52% and 58%, respectively. There were no differences in mean VA and IOP between in the right and left eyes, respectively. The changes verified in the screening of the present study exceeded 40% of ophthalmological alterations found in soccer players and contemplates the hypothesis of the study
Auditing: An analysis of scientific production in scopus
Get PDFScientific databases make it possible to keep abreast of the progress of science on various topics. This paper reviews bibliographically, the basic concepts and scientific production on auditing to analyze its frequency and trends. For this study we proceeded to collect information from the SCOPUS database, from the year 2014 to 2019 from the subarea of business and economics. Among the main results, Spain stands out as the country with the highest scientific production, with 43.55% of authors having written about auditing. Latin American countries do not present a greater participation in articles related to auditing: Ecuador reached 7.2%, Colombia 2.9% and Brazil 13%. The information reflects that most of the work done has been applied to the private sector, focusing its research directly about audit consulting with 23.2% of the global total. In America, the most applied approach is that of general auditing; these studies consider the importance of audit analysis in a global manner for a company or sector. The data analyzed indicate that the countries of Europe are the ones that develop the greatest amount of scientific production, while the continents with developing countries have a low level of representativeness
Effect of body movements in the venous blood flow and lymphatic circulation
Get PDFThe studies of ballistocardiography about the effect of cardiovascular activity in body motion raised the author interest in the research of the influence of body movements in the circulatory flow in venous and lymphatic vessels. These effects follow Sir Isaac Newton laws. With the body movement, the one-way valve structure of these vessels will cause a mobilization of venous blood and lymph to the proximal side. A model was built to demonstrate the effect of oscillatory movement in a liquid flow in a system of one-way valve. There was a rise of the liquid with difference in level that ranged from 9 cm up to 34 cm, depending on the amplitude and frequency. The model tried to mimic a segment of vein with its valve, and evaluate the effectiveness of oscillatory movements in the progression of the liquid, In a preliminary study, to assess the effect of oscillatory movements on leg swelling, this movements was applied in a clinical cases. There was regression of the oedema and circumference on the leg, by oscillatory movements, that was correlated with increase in lymphatic and venous drainage. Venous stasis is a predisposing factor of venous thromboembolism. How we extrapolate from the experimental model, the oscillatory movements of the legs improving venous circulation may contribute to the prophylaxis of venous thromboembolism. In conclusion, it is of interest to study its application in some situations of venous thromboembolism risk
Spacing and places arrangements: a study of the identity symbols of the Moto Club ‘Children of Freedom’ and their representations
Get PDFThe article is the result of an ethnography carried out on a motorcycle club located in the city of Curitiba, Brazil, called the Brotherhood Children of Freedom, and seeks to understand how the members of the motorcycle club construct the category of place in different micro spaces through their greater symbols, such as the brotherhood headquarters, the badge in their vests and the trips through the roads under formation. The city is considered as a field of analysis, from the overlapping spaces and plurality individual group. In this context, it describes the identity constructions among the Brotherhood's members, their obligations and restrictions in new arrangements related to those appropriate spaces and transformed into place. It also shows how, in relations with others inside or outside the city, spaces of different scales are appropriate by the members of the Brotherhood by means of their symbols, values, beliefs and identity, to which systems of significance are attributed, such as the very notion of belonging and tradition of the Brotherhood Children of Freedom
Overview of the change in the organization of the education system in Gabon
Get PDFThe question of change in the organization is at the heart of the concerns of public policy managers. This article proposes to analyze the management of organizations in the educational system in Gabon. We have examined what is said and what is best done in the field in an attempt to identify this consideration by the theorists of change. As pointed out by several authors, particularly those who have investigated this issue, change is a stakeholder in the management of organizations. At the end of this literature review, we found that Gabon is not the only country to be confronted with the problem of change management in its education system. In conducting an education reform, it must take into account the balance of power within the organization. In order for the organization to achieve its goal, communication must become a permanent feature of human resources management. Thus, changing the education system is a titanic but achievable undertaking. The competence of the managers, the piloting mode and the management of human resources are determining factors in the process of change
Physiological, morphological characteristics and blood profile of female elite Brazilian soccer players according to position
Get PDFThe main goal of this study was to identify the performance parameters and blood profile found among female soccer players. The second aim was to examine if there were any systematic differences between players assigned to different playing positions. Thirty-six players (age: 23.7 ± 3.5 y; weight: 61.9 ± 5.7 kg; height: 165.7± 6.2 cm) underwent a set of laboratory tests (cardiopulmonary exercise test, skinfold measurements, Wingate test, sit-and-reach test, and blood biochemical tests). The following results were verified: maximal oxygen uptake (53±3.9 mL.kg-1.min-1), second ventilatory threshold (11.5 ± 0.8 km.h-1), body fat (14.1 ± 2.9%), Wingate anaerobic test (peak power: 9.5 ± 0.8 w.kg-1; mean power: 7.3 ± 0.4 w.kg-1 and fatigue index: 55.5 ± 4.9%), flexibility test [sit-and-reach] (18.1 ± 2.9 cm) and biochemical parameters of blood (Hb:13.9 ± 0.3 g.dL-1; iron: 85.2 ± 12.6 µ.dL-1; calcium: 9.2±0.5 mg.dL-1; total cholesterol: 204.7 ± 34.7 mg.dL-1; HDL-c: 50.7± 3.6 mg.dL-1; LDL-c: 125.8± 23.3 mg.dL-1; triglycerides: 96.8±18.5 mg.dL-1). In conclusion, the current results indicate that present elite players' physiological characteristics are similar to those previously shown, despite the rapid changes of the female soccer game worldwide. However, data showed that different playing positions had different physiological and anthropometrics differences.
Brazilian soap opera and American TV series: narrativity according Barthes
Get PDFAbstract: This paper aims to compare two audiovisual tv products: a Brazilian soap opera “Avenida Brasil” (Brazil Avenue, 2012) and an American TV series Grey´s Anatomy (2005). The theoretical and methodological approach are structural narratology studies and French Semiotics, based on narratology studies influenced by Propp, Greimas and Barthes. The main goal is to analyze and compare the narrative structure of the first episodes of both TV productions by means the cardinal and catalyzer functions according to Roland Barthes narratives point of view.Keywords: brazilian soap opera, tv series, structural narratology, semiotic
Studying the rate of polyphenol oxidase activity in apples using a colorimeter
No full textSalt is one of the oldest methods used to preserve food and help it stay fresh by preventing rotting due to its antibacterial properties. This study was therefore conducted to understand how the increase in salt concentration affects the rate of change of polyphenol oxidase activity in apples using a colorimeter. A colorimeter is a device used to measure absorbance of particular wavelengths of light by specific solutions, in this case, Granny Smith Apple juice. The results correlated with the hypothesis which is predicted that as the salt concentration of the dilutions increase, there will be a decrease in the rate of change of absorbance because the chlorine ions from the salt will inhibit the polyphenol oxidase activity and prevent further oxidation of phenols to quinones, limiting the polymerization and formation of melanin. The results confirm that salt is a non-competitive inhibitor of polyphenol oxidase because it slows down the catabolic processes in apples- mainly the breakdown of glucose. However, salt is a non-competitive inhibitor of PPO but as for lower concentrations, such as 0.25M and 0.50M, the higher concentration of substrates still mitigates the effect of salt as an inhibitor to a significant extent