425 research outputs found
Examining the accumulated oxygen deficit method in breaststroke swimming
The present study investigated the accumulated oxygen deficit (AOD) method in breaststroke swimming with the aims to assess the reliability of the oxygen uptake/swimming velocity regression line and to quantify the precision of the AOD. Sixteen male swimmers performed two swimming tests in different days, with a 24-h recovery between tests: a graded swimming test and an all-out test. The all-out test was performed in one of two distances: 100 m (n = 7) or 200 m (n = 9). Through all testing, expired gases were collected breath by breath and analysed with a K4b2 Gas Analyser (Cosmed, Rome, Italy) connected to an AquaTrainer Valve (Cosmed, Rome, Italy). The standard error of the regression lines was approximately 5-6 ml kg(-1) min(-1) and the regressions allowed an extrapolation of the energy cost to higher intensities with a standard error of the predicted value that was lower in the 200-m bout (approximately 3.5 ml kg(-1) min(-1)) comparatively to the 100-m bout (approximately 6 ml kg(-1) min(-1)). The AOD imprecision was calculated as the square root of the sum of the oxygen uptake measurement error and the standard error of the predicted value for energy cost. AOD imprecision was smaller in the 200-m bout (approximately 9 ml kg(-1) min(-1)) comparatively to the 100-m bout (approximately 12 ml kg(-1) min(-1)). However, since the AOD values during the two distances were small, the AOD relative errors can be viewed as high. Additionally, the data variability was considerable (95% confidence intervals of the linear extrapolation larger than 20 ml kg(-1) min(-1)).info:eu-repo/semantics/publishedVersio
In vivo antifungal activity of neem oil and aqueous extracts against leaf spot disease caused by Cercospora abelmoschii on okra
The cercospora leaf spot, caused by Cercospora abelmoschi Ellis and Everhart, is quite common in okra culture. Therefore, this study aimed to evaluate the efficiency of aqueous extracts of neem (Azadirachta indica A. Juss), citronella (Cymbopogon nardus (L.) Rendle), eucalyptus (Eucalyptus grandis L.), ecolife®, A. indica oil and fungicide cercobin 700 PM® in control of cercospora leaf spot on okra in greenhouse. The extracts and neem oil were tested in concentration 10%, the fungicide cercobin 700PM® in dose 2.5 g.l-1, applied 10 days after pathogen inoculation by leaf spray and the citric biomass extract ecolife® in concentration 5.0 ml.l-1, applied 10 days before pathogen inoculation. All treatments, except ecolife®, were effective in controlling cercospora leaf spot and may be recommended as alternatives in agroecological systems. © JASEMKeywords: Abelmoschus esculentus, aqueous extracts, Cercospora abelmoschi, fungicide cercobin andgreenhouse
Can 8-weeks of Training Affect Active Drag in Young Swimmers?
The aim of this study was to assess the effects of 8-weeks of training on active drag in young swimmers of both genders. Eight girls and twelve boys' belonging to the same swimming team and with regular competitive participation in national and regional events for the previous two seasons participated in this study. Active drag measurements were conducted in two different evaluation moments: at the beginning of the season and after 8 weeks of training (6.0 ± 0.15 training units per week, 21.00 ± 3.23 km per week and 3.50 ± 0.23 km per training unit). The maximal swimming velocity at the distance of 13 m, active drag and drag coefficient were measured on both trials by the method of small perturbations with the help of an additional hydrodynamic body. After 8 weeks of training, mean active drag (drag force and drag coefficient) decreased in girls and boys, although no significant differences were found between the two trials. It seems that 8 weeks of swimming training were not sufficient to allow significant improvements on swimming technique. Key pointsThe velocity perturbation method seems to be a good, simple and reliable approach to assess active drag in young swimmers.Eight weeks of swimming training were not sufficient to allow significant improvements on swimming hydrodynamics.There were no differences between boys and girls concerning active drag. A possible explanation may be related to the similar values of body mass and height in boys and girls found in this study.Specific training sets concerning technique correction and improvement in young swimmers might be a main aim during training planning.info:eu-repo/semantics/publishedVersio
THE STUDY OF SWIMMERS’S HAND AND FOREARM USING COMPUTATIONAL FLUID DYNAMICS
Computational Fluid Dynamics has been widely used in biomechanics studies applied to medicine and sport. In this study we developed a 3-D model for swimmer’s hand/forearm
forces using Computational Fluid Dynamics. Models used in the simulations were created in CAD, based on realistic dimensions of a right adult human hand/forearm. The
governing system of equations considered was the incompressible Reynolds averaged Navier-Stokes equations implemented with Fluent® code. The drag coefficient was the
main responsible for propulsion, with a maximum value of force propulsion corresponding to a pitch angle of 90º. The lift coefficient seemed to play a less important role in the
generation of propulsive force with pitch angles of 0º and 90º but it is important with a pitch angle of 45º. It was demonstrated the relevance of applying CFD in the propulsive
force measurements, using a more realistic model of a human segment
UMA ANÁLISE DO PROCESSO DE GESTÃO DA EDUCAÇÃO A DISTÂNCIA EM UMA UNIVERSIDADE PÚBLICA DA REGIÃO SUDESTE
Este trabalho tem como objetivo analisar os processos de gestão da educação a distância (EaD) em instituições públicas de ensino superior (IPES). O trabalho se baseia em um estudo de caso em uma IPES. Os dados foram coletados por meio de entrevistas semi-estruturadas e pesquisa documental. Foi possível observar que o surgimento da EaD na IPES estudada apresentou características bastante específicas. Até o advento da Universidade Aberta do Brasil (UAB), a EaD sequer constava no Plano de Desenvolvimento Institucional (PDI) da IPES. Constatou-se que a IPES estudada não tem de fato políticas bem definidas para a EaD. Ela ainda depende muito das iniciativas isoladas de alguns poucos docentes. A EAD não está consolidada na instituição e não há de fato interesse da sua alta gestão em expandir as ações. A estrutura administrativa e acadêmica é muito rígida e dificulta o desenvolvimento das ações de EaD, em especial em termos de prazos para aprovações de projetos e relatórios. Editais da UAB têm sido abertos recentemente e projetos não têm sido enviados. O setor de apoio à EaD da instituição atua satisfatoriamente como suporte administrativo para os cursos a distância em funcionamento
Ultrasonic pilot-scale reactor for enzymatic bleaching of cotton fabrics
The potential of ultrasound-assisted technology has been demonstrated by several laboratory scale studies. However, their successful industrial scaling-up is still a challenge due to the limited pilot and commercial sonochemical reactors. In this work, a pilot reactor for laccase-hydrogen peroxide cotton bleaching assisted by ultrasound was scaled-up. For this purpose, an existing dyeing machine was transformed and adapted by including piezoelectric ultrasonic devices. Laboratory experiments demonstrated that both low frequency, high power (22 kHz, 2100 W) and high frequency, low power ultrasounds (850 kHz, 400 W) were required to achieve satisfactory results. Standard half (4 g/L H2O2 at 90 ºC for 60 min.) and optical (8 g/L H2O2 at 103 ºC for 40 min.) cotton bleaching processes were used as references. Two sequential stages were established for cotton bleaching: (1) laccase pretreatment assisted by high frequency ultrasound (850 kHz, 400 W) and (2) bleaching using high power ultrasound (22 kHz, 2100 W). When compared with conventional methods, combined laccase-hydrogen peroxide cotton bleaching with ultrasound energy improved the whitening effectiveness. Subsequently, less energy (temperature) and chemicals (hydrogen peroxide) were needed for cotton bleaching thus resulting in costs reduction. This technology allowed the combination of enzyme and hydrogen peroxide treatment in a continuous process. The developed pilot-scale reactor offers an enhancement of the cotton bleaching process with lower environmental impact as well as a better performance of further finishing operations.The author Idalina Goncalves would like to acknowledge the Cottonbleach Project (FP7-SME-2008-2; 243529-2-cottonbleach) for the funding. This work was partly supported by FEDER through POFC-COMPETE and by Portuguese funds from FCT- Fundacao para a Ciencia e a Tecnologia through the project PEst-OE/BIA/ Ul4050/2014. The author Carla Silva would like to acknowledge FCT - Fundacao para a Ciencia e a Tecnologia for the Grant SFRH/ BPD/46515/2008
TARSAL TUNNEL SYNDROME: A STILL CHALLENGE CONDITION
Tarsal tunnel syndrome is a rare, under diagnosed and often confused neuropathy with other clinical entities. There is a lack of population studies on this disease. Herein, we performed a non-systematic review of articles between January 1992 and February 2018. Although with a less complex anatomy comparing to the carpal tunnel, the tarsal tunnel is source of pain and some other conditions. Treatmentinvolves conservative measures such as analgesics and physical therapy rehabilitation or surgical procedures in case of conservative treatment failure. Randomized control studies are lack and mandatory for uncover the best modality of treatment for this condition
In silico identification and characterization of novel microsatellite loci for the Blue-and-yellow Macaw Ara ararauna (Linnaeus, 1758) (Psittaciformes, Psittacidae)
The illegal trade is a major threat to many bird species, and parrots are common victims of this activity. Domestic and international pet markets are interested on different parrot species, such as the Blue-and-yellow Macaw (Ara ararauna). This South American macaw is not globally threatened, but is under protection from over-exploitation. This study aimed to identify and characterize novel microsatellite loci for population and parentage analysis of A. ararauna. Scaffold sequences of Ara macao available in the NCBI database were used for microsatellite searches using MsatCommander software. We tested a total of 28 loci, from which 25 were polymorphic, one was monomorphic, and two did not generated amplification products. For polymorphic loci, the mean number of alleles was 8.24 (4 – 15 alleles per locus), the observed heterozygosity ranged from 0.333 to 0.917, and the expected heterozygosity from 0.353 to 0.890. The paternity exclusion probability and identity probability were highly discriminatory. Thus, these novel microsatellite markers can be useful for population assignment and paternity tests, helping the authorities to manage macaws from the illegal trafficking and control commercial breeders
Effects of high-intensity interval and moderate-intensity continuous exercise on inflammatory, leptin, IgA, and lipid peroxidation responses in obese males
Purpose: To compare the effects of a single high-intensity interval exercise session (HIIE) with amoderate-intensity continuous exercise session (MICE) on the inflammatory profile, IgA levels, and lipid peroxidation in sedentary obese males. Methods: Ten sedentary obese men (age 28.5 ± 2.7 years; BMI 35.9 ± 4.9 kg/m2; body fat 40.6 ± 2.0%) performed three experimental sessions, on separate days with 1 week wash-out period between interventions, according to a randomized order: (1) HIIE: 10 × 60 s at 90% of the HRmax alternated by 60 s of active recovery; (2) MICE: 20min at 70% of the HRmax; (3) Rest—control. Blood and saliva samples were collected before, immediately after and 60min after the end of each session in order to analyse serum levels of cytokines, IgA, and lipoperoxidation markers. Results: Leptin levels decreased immediately after HIIE (P = 0.033) and was different from the MICE (P = 0.025). IFN-g levels were reduced immediately after (P = 0.032) and 60min after HIIE (P = 0.003) compared to baseline, and it also increased IL-4 levels immediately after exercise (P = 0.007) compared to resting values. MICE promoted an increase in IFN-g levels immediately after exercise (P = 0.025) and 60min after exercise (P = 0.004) in relation to baseline. Both exercise conditions increased IL-6 levels up to 60min after exercise (P < 0.05). The IFN-g/IL-4 ratio decreased immediately after (P = 0.002) and 60min after HIIE (P = 0.005) in relation to pre-exercise. No changes were found for IgA-S and TBARS for any of the conditions. Conclusion: A single HIIE session is able to decrease IFN-g/IL-4 ratio, indicating an anti-inflammatory response, without alterations in the function of the mucosal immune systemand lipoperoxidation. On the other hand, a brief session ofMICE induced changes in the pattern of cytokines associated with increased cellular immune function
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