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We have studied the effects of individual and combined treatment of insulin (I) and naringin (NAR) on the bone structure and biomechanical properties of femurs from streptozotocin (STZ)-induced diabetic rats. Male Wistar rats were divided into five groups: (1) controls, (2) STZ-induced diabetic rats, (3) STZ-induced diabetic rats treated with I, (4) STZ-induced diabetic rats treated with NAR, and (5) STZ-induced diabetic rats treated with I + NAR. Bone mineral density (BMD), bone histomorphometry, biomechanical testing, and bone biomarker expressions were accomplished in femur of all animals, as well as serum biochemical analyses. The combined treatment of I + NAR increased the body weight and the femur BMD from STZ-induced diabetic rats. The bone biomechanical properties and the bone morphology of the femurs from STZ-induced diabetic rats were also improved by the combined treatment. The increased number of osteoclasts in STZ-induced diabetic rats was partially prevented by I, NAR, or I + NAR. NAR or I + NAR completely blocked the decrease in the number of osteocalcin (+) cells in the femur from STZ-induced diabetic rats. RUNX family transcription factor 2 immunostaining was much lower in STZ-induced diabetic rats than in control animals; the combination of I + NAR totally blocked this effect. The combined treatment not only ameliorated bone quality and function, but also normalized the variables related to glucose metabolism. Therefore, the combination of I + NAR might be a better therapeutic strategy than the individual I or NAR administration to reduce bone complications in diabetic patients.

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RESUMEN El fútbol es un deporte de varias acciones motrices, donde la recepción del balón se clasifica como una acción de control a diferentes alturas, velocidades y ángulos. El jugador debe tener la capacidad de receptar el balón para poder generar una acción diferente: un pase, tiro o driblar; su optimización implica mayores probabilidades de rendimiento técnico-táctico. En tal sentido, se planteó como objetivo de la investigación analizar biomecánicamente la técnica de la recepción a media altura en futbolistas profesionales y amateurs a partir de video análisis como método de medición. La investigación fue descriptiva-explicativa de orden correlacional, se analizan cuatro variables del movimiento motriz (D: distancia Recorrida; AM: aceleración máxima; VM: velocidad máxima y AF: amplitud de la articulación femorotibial) a través de video-análisis con Kinovea. Se estudiaron a cinco jugadores profesionales (grupo 1) y 15 de nivel amateur (grupo 2). Los futbolistas de nivel amateur presentaron una mayor media en todas las variables estudiadas, "D" (grupo 1: 72.17cm; grupo 2: 101.27cm; p=0.001), "AM" (grupo 1: 61.84m/s2; grupo 2: 101.73m/s2; p=0.000), "VM" (grupo 1: 8.18m/s; grupo 2: 12.55m/s; p=0.000) y "AF" (grupo 1: 62.6°; grupo 2: 75.2°; p=0.002), lo cual se comporta significativamente diferentes en todos los casos. El análisis biomecánico realizado a futbolistas profesionales y amateurs, en la técnica de recepción del balón a media altura, concluye que en los jugadores amateur requieren un mayor perfeccionamiento técnico, independientemente de su experiencia en competencias.

RESUMO O futebol é um esporte de várias ações motoras, onde a recepção da bola é classificada como uma ação de controle em diferentes alturas, velocidades e ângulos. O jogador deve ter a capacidade de receber a bola para poder gerar uma ação diferente: um passe, um chute ou um drible; sua otimização implica em maiores probabilidades de desempenho técnico-tático. Neste sentido, o objetivo da pesquisa era analisar biomecanicamente a técnica de recepção em meia altura em jogadores profissionais e amadores de futebol utilizando a análise de vídeo como método de medição. A pesquisa foi descritiva-explicativa de ordem correlacional, quatro variáveis de movimento motor (D: distância coberta; MA: aceleração máxima; MV: velocidade máxima e FA: amplitude da articulação femorotibial) foram analisadas através de vídeo-análise com Kinovea. Foram estudados cinco jogadores profissionais (grupo 1) e 15 jogadores amadores (grupo 2). Os jogadores de futebol de nível amador apresentaram uma média maior em todas as variáveis estudadas, "D" (grupo 1: 72,17cm; grupo 2: 101,27cm; p=0,001), "AM" (grupo 1: 61,84m/s2; grupo 2: 101. 73m/s2; p=0,000), "VM" (grupo 1: 8,18m/s2; grupo 2: 12,55m/s; p=0,000) e "AF" (grupo 1: 62,6°; grupo 2: 75,2°; p=0,002), que se comportam de forma significativamente diferente em todos os casos. A análise biomecânica realizada sobre jogadores profissionais e amadores de futebol, na técnica de recepção de bola em altura média, conclui que os jogadores amadores requerem um maior aperfeiçoamento técnico, independentemente de sua experiência em competições.

ABSTRACT Soccer is a sport of various motor actions, where the reception of the ball is classified as a control action at different heights, speeds and angles. The player must have the ability to receive the ball in order to generate a different action: a pass, shot or dribble; its optimization implies greater probabilities of technical-tactical performance. In this sense, the objective of the research was to biomechanically analyze the mid-height reception technique in professional and amateur soccer players using video analysis as a measurement method. The research was descriptive-explanatory of correlational order, four variables of the motor movement (D: distance covered; AM: maximum acceleration; VM: maximum speed and AF: amplitude of the femorotibial joint) are analyzed through video-analysis with Kinovea . Five professional players (group 1) and 15 amateur players (group 2) were studied. The amateur soccer players presented a higher mean in all the variables studied, "D" (group 1: 72.17cm; group 2: 101.27cm; p=0.001), "AM" (group 1: 61.84m/s 2 ; group 2: 101.73m/s 2 ; p=0.000), "VM" (group 1: 8.18m/s; group 2: 12.55m/s; p=0.000) and "AF" (group 1: 62.6°; group 2 : 75.2°; p=0.002), which behaves significantly different in all cases. The biomechanical analysis carried out on professional and amateur soccer players, in the technique of receiving the ball at mid-height, concludes that amateur players require greater technical improvement, regardless of their experience in competitions.

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BACKGROUND: Medial column instability is a frequent finding in patients with flatfeet and hallux valgus, within others. The etiology of hallux valgus is multifactorial, and medial ray axial rotation has been mentioned as having an individual role. Our objective was to design a novel cadaveric foot model where we could re-create through progressive medial column ligament damage some components of a hallux valgus deformity. METHODS: Ten fresh-frozen lower leg specimens were used, and fluorescent markers were attached in a multisegment foot model. Constant axial load and cyclic tibial rotation (to simulate foot pronation) were applied, including pull on the flexor hallucis longus tendon (FHL). We first damaged the intercuneiform (C1-C2) ligaments, second the naviculocuneiform (NC) ligaments, and third the first tarsometatarsal ligaments, leaving the plantar ligaments unharmed. Bony axial and coronal alignment was measured after each ligament damage. Statistical analysis was performed. RESULTS: A significant increase in pronation of multiple segments was observed after sectioning the NC ligaments. Damaging the tarsometatarsal ligament generated small supination and varus changes mainly in the medial ray. No significant change was observed in axial or frontal plane alignment after damaging the C1-C2 ligaments. The FHL pull exerted a small valgus change in segments of the first ray. DISCUSSION: In this biomechanical cadaveric model, the naviculocuneiform joint was the most important one responsible for pronation of the medial column. Bone pronation occurs along the whole medial column, not isolated to a certain joint. Flexor hallucis longus pull appears to play some role in frontal plane alignment, but not in bone rotation. This model will be of great help to further study medial column instability as one of the factors influencing medial column pronation and its relevance in pathologies like hallux valgus. CLINICAL RELEVANCE: This cadaveric model suggests a possible influence of medial column instability in first metatarsal pronation. With a thorough understanding of a condition's origin, better treatment strategies can be developed.

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Motion analysis is an area with several applications for health, sports, and entertainment. The high cost of state-of-the-art equipment in the health field makes it unfeasible to apply this technique in the clinics' routines. In this vein, RGB-D and RGB equipment, which have joint tracking tools, are tested with portable and low-cost solutions to enable computational motion analysis. The recent release of Google MediaPipe, a joint inference tracking technique that uses conventional RGB cameras, can be considered a milestone due to its ability to estimate depth coordinates in planar images. In light of this, this work aims to evaluate the measurement of angular variation from RGB-D and RGB sensor data against the Qualisys Tracking Manager gold standard. A total of 60 recordings were performed for each upper and lower limb movement in two different position configurations concerning the sensors. Google's MediaPipe usage obtained close results compared to Kinect V2 sensor in the inherent aspects of absolute error, RMS, and correlation to the gold standard, presenting lower dispersion values and error metrics, which is more positive. In the comparison with equipment commonly used in physical evaluations, MediaPipe had an error within the error range of short- and long-arm goniometers.

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Robotic devices can provide physical assistance to people who have suffered neurological impairments such as stroke. Neurological disorders related to this condition induce abnormal gait patterns, which impede the independence to execute different Activities of Daily Living (ADLs). From the fundamental role of the ankle in walking, Powered Ankle-Foot Orthoses (PAFOs) have been developed to enhance the users' gait patterns, and hence their quality of life. Ten patients who suffered a stroke used the actuation system of the T-FLEX exoskeleton triggered by an inertial sensor on the foot tip. The VICONmotion capture system recorded the users' kinematics for unassisted and assisted gait modalities. Biomechanical analysis and usability assessment measured the performance of the system actuation for the participants in overground walking. The biomechanical assessment exhibited changes in the lower joints' range of motion for 70% of the subjects. Moreover, the ankle kinematics showed a correlation with the variation of other movements analyzed. This variation had positive effects on 70% of the participants in at least one joint. The Gait Deviation Index (GDI) presented significant changes for 30% of the paretic limbs and 40% of the non-paretic, where the tendency was to decrease. The spatiotemporal parameters did not show significant variations between modalities, although users' cadence had a decrease of 70% of the volunteers. Lastly, the satisfaction with the device was positive, the comfort being the most user-selected aspect. This article presents the assessment of the T-FLEX actuation system in people who suffered a stroke. Biomechanical results show improvement in the ankle kinematics and variations in the other joints. In general terms, GDI does not exhibit significant increases, and the Movement Analysis Profile (MAP) registers alterations for the assisted gait with the device. Future works should focus on assessing the full T-FLEX orthosis in a larger sample of patients, including a stage of training.

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This study aimed to perform motor action and biomechanical analysis of techniques in female judo athletes separated by weight categories of 638 female bouts (103 extra lightweight <48 kg, 140 half lightweight 48>52 kg, 65 lightweight 52>57 kg, 73 half middleweight 57>63 kg, 77 middleweight 63>70 kg, 80 half heavyweight 70>78 kg and 60 heavyweight >78 kg). All bouts were analyzed following the phases of approach, gripping, defensive action, attack, also biomechanical analysis of techniques and groundwork was performed (p ≤ .05). Results indicated that lightweight athletes presented lower attempts to grip, right collar grip and left collar grip frequencies than other categories. Extra lightweight judokas presented lower right back grip and left back and sleeve grip frequencies as well as lower occurrence of techniques with arm and leg lever scored than half lightweight athletes, while half lightweight athletes demonstrated higher frequency of techniques with waist lever variable scored than lightweight ones. These findings should be considered for training prescription.

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BACKGROUND: Protective mechanical ventilation (MV) aims at limiting global lung deformation and has been associated with better clinical outcomes in acute respiratory distress syndrome (ARDS) patients. In ARDS lungs without MV support, the mechanisms and evolution of lung tissue deformation remain understudied. In this work, we quantify the progression and heterogeneity of regional strain in injured lungs under spontaneous breathing and under MV. METHODS: Lung injury was induced by lung lavage in murine subjects, followed by 3 h of spontaneous breathing (SB-group) or 3 h of low Vt mechanical ventilation (MV-group). Micro-CT images were acquired in all subjects at the beginning and at the end of the ventilation stage following induction of lung injury. Regional strain, strain progression and strain heterogeneity were computed from image-based biomechanical analysis. Three-dimensional regional strain maps were constructed, from which a region-of-interest (ROI) analysis was performed for the regional strain, the strain progression, and the strain heterogeneity. RESULTS: After 3 h of ventilation, regional strain levels were significantly higher in 43.7% of the ROIs in the SB-group. Significant increase in regional strain was found in 1.2% of the ROIs in the MV-group. Progression of regional strain was found in 100% of the ROIs in the SB-group, whereas the MV-group displayed strain progression in 1.2% of the ROIs. Progression in regional strain heterogeneity was found in 23.4% of the ROIs in the SB-group, while the MV-group resulted in 4.7% of the ROIs showing significant changes. Deformation progression is concurrent with an increase of non-aerated compartment in SB-group (from 13.3% ± 1.6% to 37.5% ± 3.1%), being higher in ventral regions of the lung. CONCLUSIONS: Spontaneous breathing in lung injury promotes regional strain and strain heterogeneity progression. In contrast, low Vt MV prevents regional strain and heterogeneity progression in injured lungs.

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Resumen En el presente trabajo se plantea un análisis biomecánico de una prótesis de cadera bajo condiciones de cargas estáticas asociadas a actividades cotidianas, en el cual se comparan tres materiales metálicos para la fabricación de una prótesis personalizada a partir de imágenes médicas. Se utilizaron plataformas en la nube de diseño asistido por computadora y de análisis por elementos finitos. Se diseñaron dos modelos de la prótesis a analizar, uno hueco y otro sólido mediante curvas spline paramétricas. Para el análisis biomecánico se requirió un tamaño de malla de 2,537,684 de elementos tetraédricos y 471,335 nodos para estudiar siete casos de posturas para una persona de 75 kg de peso, mismos que se analizaron tomando como materiales base acero inoxidable 316L, aleación Ti-6AL-4V y L-605. Se observó que con actividades tales como trotar, subir y bajar escaleras los materiales 316L y L-605, presentan el riesgo de deformación plástica e inclusive fractura. Los resultados mostraron que el material más idóneo para la fabricación de este tipo de prótesis es el Ti-6Al-4V, además de que este nos permite realizar modelos tanto sólidos como huecos, suponiendo este último, un ahorro de material y proporcionando mayor ligereza en la prótesis.

Abstract This paper shows a biomechanical analysis of a hip prosthesis under conditions of static loads associated with daily activities. For which it compared three metallic materials for the manufacture of a customized prosthesis from medical images, it was used cloud platforms with computer-aided design and finite element analysis. Two models of prosthesis one hollow and the other one solid using parametric spline curves were designed and analyzed. The biomechanical analysis required a mesh size consisting of 2,537,684 tetrahedral elements and 471,335 nodes to study seven cases of postures for a person weighing 75 kg. These cases were analyzed based on 316L stainless steel, Ti-6AL-4V alloy, and another L-605 alloy. It was observed that with activities such as jogging, climbing and descending stairs, materials 316L, and L-605 present the risk of plastic deformation and even fracture. The results show that the most suitable material for the manufacture of this type of prosthesis is the Ti-6Al-4V, which allows us to make both solid and hollow models. Assuming this last material is saved and improves the prosthesis lightness.

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The goal of this study is the assessment of an assistive control approach applied to an active knee orthosis plus a walker for gait rehabilitation. The study evaluates post-stroke patients and healthy subjects (control group) in terms of kinematics, kinetics, and muscle activity. Muscle and gait information of interest were acquired from their lower limbs and trunk, and a comparison was conducted between patients and control group. Signals from plantar pressure, gait phase, and knee angle and torque were acquired during gait, which allowed us to verify that the stance control strategy proposed here was efficient at improving the patients' gaits (comparing their results to the control group), without the necessity of imposing a fixed knee trajectory. An innovative evaluation of trunk muscles related to the maintenance of dynamic postural equilibrium during gait assisted by our active knee orthosis plus walker was also conducted through inertial sensors. An increase in gait cycle (stance phase) was also observed when comparing the results of this study to our previous work. Regarding the kinematics, the maximum knee torque was lower for patients when compared to the control group, which implies that our orthosis did not demand from the patients a knee torque greater than that for healthy subjects. Through surface electromyography (sEMG) analysis, a significant reduction in trunk muscle activation and fatigability, before and during the use of our orthosis by patients, was also observed. This suggest that our orthosis, together with the assistive control approach proposed here, is promising and could be considered to complement post-stroke patient gait rehabilitation.

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Resumen Las expectativas actuales del deporte contemporáneo han impuesto retos que necesariamente implican, desde posiciones de ciencia, la búsqueda constante de nuevas tecnologías que permitan elevar el resultado deportivo de los atletas, de lo cual no ha quedado exento el kárate-do. En la presente investigación, se realizó un estudio de las características biomecánicas que tributan al cumplimiento del patrón técnico de la patada Mawash Geri Jodan, con el objetivo de proponer el procedimiento para su análisis, considerando los indicadores biomecánicos que garantizan su patrón técnico. Para ello, se trabajó con una muestra de seis atletas de los dojos del municipio Pinar del Río, así como una muestra secundaria de seis entrenadores y ocho especialistas. Se emplearon métodos y técnicas científicas de investigación como el analítico-sintético, inductivo-deductivo, análisis de documentos, la observación, la entrevista, la videografía, medición y el criterio de expertos. Para lograr el propósito, se tomó como referencia una metodología, identificando las características biomecánicas que contribuyen al resultado de esta técnica, las que fueron complementadas por el análisis del modelo determinístico construido. Una vez seleccionadas las características biomecánicas que posibilitan la ejecución exitosa de esta técnica, se procedió, mediante el criterio de expertos, al análisis cuantitativo de las variables con su correspondencia, en la incidencia del resultado de la ejecución del movimiento técnico mediante la videograbación. Las características biomecánicas determinadas, que aparecen en el modelo determinístico construido para la técnica, son factibles para el análisis de la calidad de la ejecución de esta patada.

Resumo As expectativas atuais do desporto contemporâneo impuseram desafios que implicam necessariamente, a partir de posições da ciência, a constante procura de novas tecnologias que permitam aos atletas elevar o seu desempenho desportivo, do qual o karate-do não tem sido isento. Na presente investigação foi realizado um estudo das características biomecânicas que contribuem para o cumprimento do padrão técnico do pontapé Mawashi Geri Jodan, com o objectivo de propor o procedimento para a sua análise, considerando os indicadores biomecânicos que garantem o seu padrão técnico. Para isso, foi trabalhada uma amostra de seis atletas dos dojos do município de Pinar del Río, assim como uma amostra secundária de seis treinadores e oito especialistas. Foram utilizados métodos e técnicas de pesquisa científica, tais como análise analítico-sintética, indutivo-dedutiva, análise documental, observação, entrevista, videografia, medição e julgamento por especialistas. Para alcançar o objetivo, tomou-se como referência uma metodologia, identificando as características biomecânicas que contribuem para o resultado desta técnica, as quais foram complementadas pela análise do modelo determinístico construído. Uma vez selecionadas as características biomecânicas que tornam possível a execução bem-sucedida desta técnica, a análise quantitativa das variáveis com sua correspondência na incidência do resultado da execução do movimento técnico por meio da gravação em vídeo foi realizada por meio de critérios de especialistas. As determinadas características biomecânicas que aparecem no modelo determinístico construído para a técnica, são viáveis para a análise da qualidade da execução deste chute.

Abstract The current expectations of contemporary sport have imposed challenges that necessarily imply, from positions of science, the constant search for new technologies that will allow athletes to raise their sporting performance, from which karate-do has not been exempt. In the present research, a study of the biomechanical characteristics that contribute to the fulfillment of the technical pattern of the Mawashi Geri Jodan kick was carried out, with the objective of proposing the procedure for its analysis, considering the biomechanical indicators that guarantee its technical pattern. For this purpose, a sample of six athletes from the dojos of the Pinar del Río municipality was worked on, as well as a secondary sample of six coaches and eight specialists. Scientific research methods and techniques were used, such as analytical-synthetic, inductive-deductive, document analysis, observation, interview, videography, measurement and expert judgment. To achieve the purpose, a methodology was taken as reference, identifying the biomechanical characteristics that contribute to the result of this technique, which were complemented by the analysis of the deterministic model built. Once the biomechanical characteristics that make possible the successful implementation of this technique were selected, the quantitative analysis of the variables with their correspondence in the incidence of the result of the implementation of the technical movement through video recording was carried out by means of expert criteria. The determined biomechanical characteristics that appear in the deterministic model constructed for the technique, are feasible for the analysis of the quality of the execution of this kick.

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Introduction: Breathing produces a phenomenon of cyclic deformation throughout life. Biomechanically, deformation of the lung is measured as strain. Regional strain recently started to be recognised as a tool in the study of lung pathophysiology, but regional lung strain has not been studied in healthy subjects breathing spontaneously without voluntary or pharmacological control of ventilation. Our aim is to generate three-dimensional (3D) regional strain and heterogeneity maps of healthy rat lungs and describe their changes over time. Methods: Micro-CT and image-based biomechanical analysis by finite element approach were carried out in six anaesthetised rats under spontaneous breathing in two different states, at the beginning of the experiment and after 3 hours of observation. 3D regional strain maps were constructed and divided into 10 isovolumetric region-of-interest (ROI) in three directions (apex to base, dorsal to ventral and costal to mediastinal), allowing to regionally analyse the volumetric strain, the strain progression and the strain heterogeneity. To describe in depth these parameters, and systematise their report, we defined regional strain heterogeneity index [1+strain SD ROI(x)]/[1+strain mean ROI(x)] and regional strain progression index [ROI(x)-mean of final strain/ROI(x)-mean of initial strain]. Results: We were able to generate 3D regional strain maps of the lung in subjects without respiratory support, showing significant differences among the three analysed axes. We observed a significantly lower regional volumetric strain in the apex sector compared with the base, with no significant anatomical systematic differences in the other directions. This heterogeneity could not be identified with physiological or standard CT methods. There was no progression of the analysed regional volumetric strain when the two time-points were compared. Discussion: It is possible to map the regional volumetric strain in the lung for healthy subjects during spontaneous breathing. Regional strain heterogeneity and changes over time can be measured using a CT image-based numerical analysis applying a finite element approach. These results support that healthy lung might have significant regional strain and its spatial distribution is highly heterogeneous. This protocol for CT image acquisition and analysis could be a useful tool for helping to understand the mechanobiology of the lung in many diseases.

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BACKGROUND: Different techniques have been described for percutaneous Achilles tendon rupture repair, but no biomechanical evaluation has been performed separately for proximal and distal suturing techniques. The purpose of this study was to biomechanically analyze proximal versus distal percutaneous Achilles suture configurations during cyclic loading and load to failure. METHODS: A simulated, midsubstance rupture was created 6 cm proximal to the calcaneal insertion in fresh-frozen cadaveric Achilles tendons. Fifteen proximal specimens were divided into 3 groups: (A1) triple locking technique, (A2) Bunnell-type technique, and (A3) double Bunnell-type technique. Twelve distal specimens were divided into 2 groups: (B1) triple nonlocking technique and (B2) oblique technique. Repairs were subjected to cyclic testing and load to failure. Load to failure, cause of failure, and tendon elongation were evaluated. RESULTS: None of the proximal specimens and 7/12 of the distal ones failed in cyclic testing. The proximal fixation groups demonstrated significantly more strength than the distal groups (P = .001), achieving up to 710 N of failure load in Group A3. Groups B1and B2 failed on average at 380 N with no difference between them (P > .05). The majority of all repairs failed in the suture-tendon interface. Distal groups had more elongation during cyclic testing (13.7 mm) than proximal groups (9.4 mm) (P = .02). CONCLUSION: The distal fixation site in this Achilles tendon repair was significantly weaker than the proximal fixation site. A proximal modified suture configuration increased resistance to cyclic loading and load to failure significantly. CLINICAL RELEVANCE: A modification can be suggested to improve strength of the Achilles repair.

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Problema: en el mundial, los marchistas participan con el más alto nivel de ejecución técnica y con las mejores condiciones físicas, por lo que el análisis de los pasos de un marchista es clave para la obtención de un resultado óptimo. Objetivo: analizar la técnica del paso de un marchista de elite y el comportamiento de las variables de la marcha atlética, pre competencia al mundial de atletismo. Método: al deportista se le aplicó una prueba en una pista electrónica, evaluando las variables cinemáticas: longitud de paso, frecuencia de pasos, tiempo de vuelo y velocidad. Se utilizó ANOVA para determinar diferencias significativas (p ≤0.05). Resultados: en las tres pruebas realizadas, todas las variables incrementaron significativamente, aunque la diferencia más significativa se encontró entre tiempo de vuelo y frecuencia de pasos p=0.0000001, p<0.05. Conclusión: debido a que el tiempo de vuelo se incrementa rápidamente, se debe cuidar que no influya en la ejecución técnica del marchista para que sea más efectiva y así evitar una amonestación o descalificación.

Problem: In the World Athletics Championships, the racewalkers participate with the highest level of technical execution and with the best physical conditions, so the analysis of the steps of a racewalker is key to obtain an optimal result. Objective: To analyze the technique of an elite racewalker and the behavior of the variables of the athletic racewalking, pre-competition to the World Athletics Championships. Method: A test on an electronic track was given to one athlete, evaluating the kinematic variables: step length, step frequency, flight time, and speed. ANOVA was used to determine significant differences (p ≤0.05). Result: In the three tests carried out, all the variables increased significantly, although the most significant difference was found between flight time and step frequency p = 0.0000001, p <0.05. Conclusion: Since the flight time increases rapidly, it must be careful that this not influence the technical execution of the racewalkers, to be more effective, and thus avoid a warning or disqualification.

Problema: No mundial, os marchistas participam com o maior nível de execução técnica e com as melhores condições físicas, é por isso que a análise dos passos de um marchista é a chave para a obtenção de melhores resultados. Objetivo: analisar a técnica de passo de um marchista de elite e o comportamento das variáveis da marcha atlética, pré-competição rumo ao mundial de atletismo. Método: um teste foi aplicado em uma pista eletrônica de um marchista e se estudaram as seguintes variáveis cinemáticas: o comprimento do passo, a frequência de passos, o tempo de voo e a velocidade. ANOVA foi utilizada para determinar as diferenças significativas (p ≤0.05). Resultados: Em todos os três testes realizados, todas as variáveis aumentaram significativamente, embora a diferença mais significativa foi encontrada entre o tempo de voo e a frequência de passos p = 0.0000001, p <0,05. Conclusão: Porque o tempo de voo aumenta rapidamente, deve ser assegurado que não tenha nenhuma influência sobre a execução técnica do marchista, para que seja mais eficaz e, assim, evitar uma advertência ou desqualificação.

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The reaching of objects is usually practiced by CP children in conventional or Virtual Reality-based therapies to enhance motor skill performance. Recently, Kinesio Taping® method has been studied to increase mechanical stability and improve functional movement of the upper limb; however, its influence on CP children´s upper limb motion has been rarely quantified due to lack of sensory measurement. Therefore, in this paper, we evaluate the biomechanical and functional effects of applying shoulder Kinesio Taping® on CP children in the reaching-transporting of virtual objects, by using a low-cost tracking device, exact robust differentiation of data and a simple nonlinear biomechanical dynamic model of the trunk and arm.

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Understanding regional deformation in the lung has long attracted the medical community, as parenchymal deformation plays a key role in respiratory physiology. Recent advances in image registration make it possible to noninvasively study regional deformation, showing that volumetric deformation in healthy lungs follows complex spatial patterns not necessarily shared by all subjects, and that deformation can be highly anisotropic. In this work, we systematically study the regional deformation in the lungs of eleven human subjects by means of in vivo image-based biomechanical analysis. Regional deformation is quantified in terms of 3D maps of the invariants of the right stretch tensor, which are related to regional changes in length, surface and volume. Based on the histograms of individual lungs, we show that log-normal distributions adequately represent the frequency distribution of deformation invariants in the lung, which naturally motivates the normalization of the invariant fields in terms of the log-normal score. Normalized maps of deformation invariants allow for a direct intersubject comparison, as they display spatial patterns of deformation in a range that is common to all subjects. For the population studied, we find that lungs in supine position display a marked gradient along the gravitational direction not only for volumetric but also for length and surface regional deformation, highlighting the role of gravity in the regional deformation of normal lungs under spontaneous breathing.

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Resumen El progreso de la bioingeniería ha permitido el desarrollo de herramientas tecnológicas para cuantificar las variables asociadas al examen físico. En este artículo se presenta la descripción, ventajas y limitaciones de tecnologías para la medición de fuerza, arcos de movimiento, equilibrio y estabilidad, coordinación y marcha. Se proponen también alternativas para uso de estas tecnologías como parte del proceso de valoración de pacientes complejos, ya sea porque se sospeche simulación o porque presenten lesiones graves en las que se requiera sugerir opciones en el proceso de rehabilitación o cierre de caso. En tales circunstancias se identifican alternativas para un diagnóstico más completo que disminuyan la subjetividad del terapeuta y con mayores posibilidades de monitoreo.

Abstract The progress of bioengineering has allowed the development of technological tools to quantify the variables associated to the physical assessment process. The description, advantages and limitations of technologies to measure the strength, range of motion, balance and stability, coordination and gait are shown. Some alternatives are proposed for using those technologies as part of the appreciation process in complex patients, either for any suspicion of simulation or because any serious injury can exist where some alternatives for rehabilitation process are required. In such cases, must be identified some options for a more complete diagnosis, decreasing the subjectivity of the therapist and with more monitoring possibilities.

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BACKGROUND: Manufacturing industry workers who repair computers may be exposed to ergonomic risk factors. OBJECTIVES: This project analyzes the tasks involved in the computer repair process to (1) find the risk level for musculoskeletal disorders (MSDs) and (2) propose ergonomic interventions to address any ergonomic issues. METHODS: Work procedures and main body postures were video recorded and analyzed using task analysis, the Rapid Entire Body Assessment (REBA) postural method, and biomechanical analysis. RESULTS: High risk for MSDs was found on every subtask using REBA. Although biomechanical analysis found an acceptable mass center displacement during tasks, a hazardous level of compression on the lower back during computer's transportation was detected. CONCLUSIONS: This assessment found ergonomic risks mainly in the trunk, arm/forearm, and legs; the neck and hand/wrist were also compromised. Opportunities for ergonomic analyses and interventions in the design and execution of computer repair tasks are discussed.

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The aim of this in vitro study was to evaluate the mechanical resistance of a 2.0-mm titanium system applied to the mandibular angle, either with or without continuity of the inferior border of the mandible. Polyurethane mandibles were used as substrates and divided into two groups: unfavourable and favourable to treatment. A single cut was made through the retromolar region, simulating an angle fracture either unfavourable or favourable to treatment. In addition, a small fragment of the inferior border of the mandible was removed in some of the mandibles, creating a discontinuity. The fragments were stabilized in accordance with the technique of Champy et al. The substrates were adapted to a universal mechanical testing machine and submitted to a constant load applied at three different points; load values were obtained at three different moments of displacement: 1mm, 2mm, and fixation failure. The value of the tip dislocation at final displacement was obtained. When the load was applied at the first molars, regardless of the side, no statistically significant difference was observed between the groups. When the load was applied at the central incisors, a statistically significant difference was observed at fixation failure in the unfavourable to treatment group, with better results in the subgroup with continuity of the inferior border of the mandible compared to the subgroup without continuity. Discontinuity of the inferior border of the mandible did not decrease the mechanical resistance of the fixation.

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Objetivos: avaliar o comportamento biomecânico de três tipos de conexão protética em implantes de diâmetro reduzido. Material e Métodos: implantes com diâmetro 3,25 mm (plataforma 3,4 mm) foram inseridos em polioximetileno (poliacetal) com torque máximo de 45 Ncm e receberam componentes protéticos calcináveis divididos em três grupos: G1: cone-morse (CM), hexágono interno (HI), e Hexágono externo (HE). Todo os pilares foram sobrefundidos em liga de CoCr e aparafusados com torque de 20 Ncm conforme recomendações do fabricante. A avaliação biomecânica ocorreu conforme a norma ISO 14801-2007: carregamento compressivo 30º e fadiga cíclica (f=15Hz, 5 milhões de ciclos) em ambiente seco. A análise estatística foi conduzida usando-se os testes Anova e Tukey (nível de significância 5%). Resultados: os valores compressivos médios foram: G1 (317,43 N), G2 (559,44 N), e G3 (290,83 N). Diferenças signifi cativas foram vistas entre G1 e G2 (p < 0,001) e entre G2 e G3 (p < 0,0001). Não houve diferença entre grupos no teste de fadiga. Os valores correspondentes foram: G1 (190,80 N), G2 (163,25 N), e G3 (141,77 N). Conclusões: todos os grupos demonstraram desempenho biomecânico aceitável

Objectives: to evaluate the biomechanical behavior of three types of prosthetic abutment connections in reduced implant diameters. Material and Methods: 3.25 mm-diameter dental implants (3.4 mm implant platform) were inserted in polyoxymethylene (polyacetal) resin with maximum torque of 45Ncm and received burnout prosthetic abutments divided into three groups: G1: cone-morse (CM), Internal Hex (IH), and External Hex (EH). All abutments were overcast in a CoCr alloy and fastened to 20 Ncm following manufacturer’s instructions. Biomechanical evaluation was performed according to ISO 14801-2007 standards: 30º compressive and fatigue loading (f = 15 Hz, 5 million cycles) in dry environment. Statistical analysis was conducted with Anova and post-hoc Tukey tests (5% signifi cance level). Results: mean compressive values were: G1 (317.43 N), G2 (559.44 N), and G3 (290.83 N). Signifi cant differences were seen between G1 and G2 (p < 0.001) and between G2 and G3 (p < 0.0001). No differences among groups were seen for fatigue loading. The correspondent endurance limits were: G1 (190.80 N), G2 (163.25 N), and G3 (141.77 N). Conclusions: all groups demonstrated acceptable biomechanical performance.

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