The main aim of this study was to investigate the effect of finger spread on the propulsive force production in swimming using computational fluid dynamics. Computer tomography scans of an Olympic swimmer hand were conducted. This procedure involved three models of the hand with differing finger spreads: fingers closed together (no spread), fingers with a small (0.32 cm) spread, and fingers with large (0.64 cm) spread. Steady-state computational fluid dynamics analyses were performed using the Fluent code. The measured forces on the hand models were decomposed into drag and lift coefficients. For hand models, angles of attack of 0 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, and 90 degrees, with a sweep back angle of 0 degrees, were used for the calculations. The results showed that the model with a small spread between fingers presented higher values of drag coefficient than did the models with fingers closed and fingers with a large spread. One can note that the drag coefficient presented the highest values for an attack angle of 90 degrees in the three hand models. The lift coefficient resembled a sinusoidal curve across the attack angle. The values for the lift coefficient presented few differences among the three models, for a given attack angle. These results suggested that fingers slightly spread could allow the hand to create more propulsive force during swimming.

The aim of the present study was to analyze the hydrodynamic characteristics of a true model of a swimmer hand with the thumb in different positions using numerical simulation techniques. A three-dimensional domain was created to simulate the fluid flow around three models of a swimmer hand, with the thumb in different positions: thumb fully abducted, partially abducted, and adducted. These three hand models were obtained through computerized tomography scans of an Olympic swimmer hand. Steady-state computational fluid dynamics analyses were performed using the Fluent(®) code. The forces estimated in each of the three hand models were decomposed into drag and lift coefficients. Angles of attack of hand models of 0°, 45° and 90°, with a sweep back angle of 0° were used for the calculations. The results showed that the position with the thumb adducted presented slightly higher values of drag coefficient compared with thumb abducted positions. Moreover, the position with the thumb fully abducted allowed increasing the lift coefficient of the hand at angles of attack of 0° and 45°. These results suggested that, for hand models in which the lift force can play an important role, the abduction of the thumb may be better, whereas at higher angles of attack, in which the drag force is dominant, the adduction of the thumb may be preferable. Key pointsNumerical simulation techniques can provide answers to problems which have been unobtainable using experimental methods.The computer tomography scans allowed the creation of a complete and true digital anatomic model of a swimmer hand.The position with the thumb adducted presented slightly higher values of drag coefficient than the positions with the thumb abducted.The position with the thumb fully abducted allowed increasing the lift coefficient of the hand at angles of attack of 0 and 45 degrees.For hand positions in which the lift force can play an important role the abduction of the thumb may be better whereas at higher angles of attack, in which the drag force is dominant, the adduction of the thumb may be preferable for swimmers.

The purpose of this study was to analyze the hydrodynamic characteristics of a realistic model of an elite swimmer hand/forearm using three-dimensional computational fluid dynamics techniques. A three-dimensional domain was designed to simulate the fluid flow around a swimmer hand and forearm model in different orientations (0°, 45°, and 90° for the three axes Ox, Oy and Oz). The hand/forearm model was obtained through computerized tomography scans. Steady-state analyses were performed using the commercial code Fluent. The drag coefficient presented higher values than the lift coefficient for all model orientations. The drag coefficient of the hand/forearm model increased with the angle of attack, with the maximum value of the force coefficient corresponding to an angle of attack of 90°. The drag coefficient obtained the highest value at an orientation of the hand plane in which the model was directly perpendicular to the direction of the flow. An important contribution of the lift coefficient was observed at an angle of attack of 45°, which could have an important role in the overall propulsive force production of the hand and forearm in swimming phases, when the angle of attack is near 45°.

In everyday applications, the use of hands is essential in performing many tasks. Several situations such as car acidents, labor or stroke, impair mobility and maneuverability of the hands, forcing the individual to seek rehabilitation methods. This study aims to model and develop a device for rehabilitation of the finger that allows performthemovements of flexion / extension, within the limits of each joint. Evaluating types of fingers rehabilitation devices, they are observed its peculiarities and its main advantages, culminating in proposing an efficient model. Thus, this research presents the development of a more affordable device that meets the needs of patients in order to recover their normal activities.

The present work starts from the observation of scientific works that used the methodology of mapping the vulnerability to soil loss by Crepani et al. (2001), and questions about the adaptation or lack of analysis factors that are part of this methodology. Observing these works, it was found that most authors fail to apply or substitute geomorphological factors such as altimetric amplitude and horizontal dissection, using only the slope, differently from what is proposed by the methodology. With this, the work proposes the adaptation of the altimetric amplitude factor, replacing it with the vertical distance to the nearest drainage, called HAND, which is also applied to the mapping of land use aptitudes and the mapping of areas of susceptibility. The HAND as a method of hydrological modeling is studied as a predictor of susceptibility to hydrological disasters such as wet mass landslides and flooding. With this in mind, the main objective of the work is to propose an adaptation of the geomorphological factor of the methodology for vulnerability to soil loss, by Crepani et al. (2001). The work structure is divided into 4 sessions, the first with the theoretical framework, the second showing the applied methodology, the third session with the results and discussions and finally the final considerations about the work. The methodology was divided into two fronts, a bibliographic survey about subjects that encompass the research, as well as applications of the methodology of vulnerability to soil loss and data processing through secondary data, compilation of thematic maps and use of orbital images for the generation maps of land use and geomorphometric elements of the relief, using GIS programs. As a main result, the good response obtained by the application with the HAND model is evidenced, which presented values consistent with the study area and also results dose to those of the altimetric amplitude map, used as a comparison and observation factor. Through these points, two final maps were drawn up, the environmental vulnerability to soil loss, using the land use and cover map and the natural vulnerability to soil loss, using the vegetation factor, as evidenced by the vegetation cover . With the result of these two mappings, it was found that the hydrographic basin of the Peixe River, considered as the application area of the methodology, presented significant areas of moderately stable / vulnerable vulnerability, which according to the analyzes the main factor of this degree are the agricultura! activities and the incorrect handling of the soil, allied to some locations of busy reliefs and types of rocks and soils. As final considerations, it is possible to say that this work provides support for the application of this adaptation in other hydrographic basins, and socioeconomic factors can also be implemented for possible studies of Economic Ecological Zoning.

O objetivo do estudo foi quantificar a força muscular da mão, nos movimentos de preensão palmar e três tipos de pinça, comparando os cadetes homens e mulheres. Foram avaliados 31 cadetes da Academia da Força Aérea Basileira, sendo 17 homens e 14 mulheres, com os dinamômetros Jamar e Preston Pinch Gauge. A média de preensão das mulheres foi de 31,4 kgf no lado dominante e 29,3 kgf no lado não-dominante; nos homens, foi 43,6 e 41,2 kgf, respectivamente (p

OBJECTIVE: We aimed to evaluate the association between platelet (PLT) count and the risk and progression of hand, foot, and mouth disease (HFMD). METHODS: In total, 122 HFMD patients and 40 healthy controls were enrolled in the study. The differences between variables among the different subgroups were compared. Logistic regression analyses were performed to assess the relationship between various parameters and HFMD risk/progression. Sensitivity analysis was conducted by detecting the trend of the association between PLT count quartiles and HFMD risk/progression. A generalized additive model was used to identify the nonlinear relationship between PLT count and HFMD risk/ progression. The relationship between gender and PLT count as well as the risk/progression of HFMD was detected using a stratified logistic regression model. RESULTS: Significant differences were observed in terms of age, male/female ratio, white blood cell (WBC) count, and PLT count between patients with stage I-II, III-IV HFMD and healthy controls. Moreover, the alanine aminotransferase and magnesium levels between patients with stage I-II and III-IV HFMD significantly differed. Moreover, a significant difference was noted in the male/female ratio among the different PLT groups. The group with a low PLT count had a lower risk of HFMD progression than the group with a high PLT count (Q4) (p=0.039). Lower age, male gender, and WBC count were found to be associated with HFMD risk. Meanwhile, PLT count was correlated to HFMD progression. The sensitivity analysis yielded a similar result using the minimally adjusted model (p for trend=0.037), and minimal changes were observed using the crude and fully adjusted model (p for trend=0.054; 0.090). A significant nonlinear relationship was observed between PLT count and HFMD progression after adjusting for age, gender, and WBC (p=0.039). CONCLUSIONS: PLT was independently associated with HFMD progression in a nonlinear manner.

Pilots from Brazilian Air Force Academy (AFA) perform strentgth- and accuracy-demanding hand movements, which may modify muscle strength. The aim of this study was to analyse hand isometric strength of grip and pulp-to-pulp, tripode and lateral pinch in three groups of male AFA pilots: ADS (Air Demonstration Squadron), n=15; IP (instructor pilots), n=16; and TP (training pilots), n=6. Pilots body positioning during tests followed the standards of the American Society of Hand Therapists; the sequence of assessed movements was predefined in order to prevent muscle fatigue. The maximum isometric muscle force was collected in a contraction kept for 6 seconds. As to grip, results show significant differences within all groups, favouring dominant hands; also, mean ADS grip values were significantly higher than the other groups'. Tripode pinch ADS mean values were significantly higher than training pilots'; and dominant hands significantly overtopped non- dominant ones in ADS and IP groups. It may thus be said that specific hand muscle training during flight, as well as training specialization and duration influence hand isometric muscle strength.

Um protocolo de força de preensão manual (FPM) em degraus de intensidade foi empregado para estudo da fadiga dos músculos flexor radial do carpo (FRC) e flexor superficial dos dedos (FSD) por meio do registro da força de preensão sustentada. Foi feita a análise do sinal eletromiográfico de superfície destes músculos no domínio do tempo e da frequência de 2kHz. Foi utilizado um dinamômetro eletrônico e um conversor analógico-digital de 16 bits. Participaram deste estudo 12 indivíduos saudáveis, ativos e destros, com média de idade 21,53 ± 1,26 anos, percentual de gordura 7,76 ± 3,53%, peso corporal 74,9 ± 10,36 kg e estatura 180,69 ± 7,14 cm. Os indivíduos realizaram o teste de contração isométrica voluntária máxima (CIVM) da mão dominante seguido do protocolo de degraus submáximos em 20%, 40% e 60% da CIVM por 10 segundos cada. O processamento dos sinais envolveu a filtragem passa banda e o cálculo dos valores de raiz média quadrática (RMS) e frequência mediana (FM) em cada degrau de contração submáxima. A análise de variância "two-way" foi aplicada para os valores de RMS e FM. O teste proposto não gerou queda do rendimento de força nos degraus submáximos estabelecidos e a instauração do processo de fadiga do FSD. Por outro lado, o FRC apresentou sinais de fadiga mioelétrica sugerindo o processo de falência da FPM. Estes dados sugerem que a fadiga mioelétrica dos flexores dos dedos durante a FPM é um processo tardio à fadiga dos estabilizadores do punho. O protocolo em degrau de 60% parece desencadear o processo de fadiga mioelétrica do músculo FRC, mas não do FSD, baseado na análise da ativação muscular nos domínios do tempo e frequência.

PURPOSE AND METHODS: In order to determine forces acting upon an articular joint during hand rehabilitation, a dynamic splint was built and connected to a dynamometer (capable of measuring forces in the range 0 - 600 gf). Through trigonometric calculation, the authors measured the flexing force in the proximal interphalangeal joint of the middle finger at 30°, 45°, 60°, and 90° of flexion. Measurements were obtained in a population of 40 voluntary adults, 20 females and 20 males, This flexing force was correlated with age, sex, and anthropometric measures. RESULTS: Force in the flexing tendon is maximal at the start of flexion, and decreases as the angle of joint flexion increases. A relationship was observed between finger length and the magnitude of the force exerted on the tendon: the longer the finger, the greater the force exherted upon the tendon. Force is greater at all the measured angles, (except 30°) in males and in individuals of higher stature, and bigger arm span. CONCLUSIONS: The flexing force can be effectively measured at all flexing angles, that it correlates with a number of different anthropometric parameters, and that such data are likely to open the way for future studies.