A multi-directional wear apparatus was developed to simulate the kinematic motion of diarthrodial joints. A comprehensive evaluation including biotribological and biomechanical characterization of articular surfaces was performed with concomitant translational and oscillating rotational motion similar to that experienced in vivo. Various system parameters were evaluated in the designed experiments including normal load magnitude (high/low), surface quality (defect/no defect), and wear pattern (with/without rotation). Biomechanical characterization was achieved through stress relaxation and dynamic cyclical testing. Quasi-linear viscoelastic theory was used to curve-fit the stress relaxation data, while the dynamic data was used to determine the dynamic properties through Fast Fourier Transform analysis and verify the assumptions posed with the QLV theory.Overall tissue compression was significantly dependent on load magnitude (pstatic was significantly dependent on surface quality (pinitial was significantly dependent on both surface quality (pComparisons of the curve-fit parameters showed a significant decrease in pre- vs post-wear elastic response, A, and viscous response, c. In addition, the short term relaxation response, τ1, showed a significant decrease between no defect (0.801 ± 0.13 sec) and a defect (0.679 ± 0.16 sec). lGlpost-wear/lGlpre-wear tan δ , was generally greater while lGl was less for those specimens experiencing rotation Qualitatively, SEM photographs revealed the mechanical degradation of the tissue surface due to wear. Surfaces with a defect had increased wear debris, which ultimately contributes to third body wear. Surfaces without a defect had preferentially aligned abrasions, while those surfaces outside the wear path showed no signs of wear.Significant correlation was detected between the μstatic and μinitial for both the nonliner viscous response, B (p2 (p<0.013 and p<0.062). Thus, the comprehensive evaluation of biomechanical and biotribological characteristics suggests the new wear regime and standardization of analysis techniques will aid in the development of functional articular repair and clinical repair techniques.

O objetivo do presente estudo foi analisar, por meio de microtomografia computadorizada, as alterações bidimensionais (área e perímetro), tridimensionais (volume, área de superfície e SMI) e o transporte do canal nas raízes mesiais de molares inferiores com curvatura severa, após o preparo biomecânico realizado por quatro sistemas de NiTi variando o tipo de cinemática e conceito de preparo, a geometria e design dos instrumentos e o tipo de tratamento da liga. Dessa forma, foram avaliados o sistema rotatório de instrumentos múltiplos Protaper Next (PTN); o sistema reciprocante de instrumento único Reciproc (RC); o sistema reciprocante de instrumento único, Reciproc Blue (RCB) e o sistema rotatório de instrumentos múltiplos TRUShape (TRS). Foram selecionados 32 molares inferiores com ângulo de curvatura da raiz mesial de 25-50º e raio 4 mm, e escaneados em microtomógrafo 1176 (SkyScan, Kontich, Bélgica), com resolução isotrópica de 18 m. Após isso, as imagens foram reconstruídas e analisadas com obtenção dos parâmetros iniciais (pré-instrumentação) bidimensionais de área e perímetro, e tridimensionais de volume, área de superfície e SMI, além do transporte do canal por meio da obtenção dos valores do centroide. Os espécimes foram então distribuídos em grupos experimentais de acordo com o sistema de instrumentação utilizado (n=8), e após a instrumentação, foi realizada nova análise microtromográfica seguindo os padrões iniciais descritos. Os dados pré e pós instrumentação foram tabulados e então realizada a análise estatística por meio de ANOVA e pós teste Tukey, com nível de significância de 5%. Os resultados demonstraram que, independente do sistema de instrumentação, houve alterações dos parâmetros bidimensionais e tridimensionais, como também transporte do canal pós-instrumentação. Não foram observadas diferenças estatisticamente significantes (p>0,05) entre os sistemas RC e RCB, bem como entre os sistemas PTN e TRS em nenhum dos parâmetros analisados (bidimensionais, tridimensionais e transporte do canal). No terço cervical, foram encontradas diferenças estatisticamente significantes (p<0,05) entre os sistemas, com maiores alterações entre RC e RCB, em relação aos sistemas PTN e TRS. No terço apical, não houve diferenças estatisticamente significantes (p>0,05) entre os sistemas, em relação aos parâmetros estudados. Pode-se concluir que os sistemas em estudo, independentemente do número de instrumentos, do tipo de movimento, do tipo de tratamento térmico das ligas e das características particulares de cada instrumento, não promoveram alterações na zona crítica apical, e que os instrumentos de maior conicidade promoveram maiores mudanças na morfologia do canal, de acordo com os parâmetros avaliados / The aim of the present study was to analyze, by micro-CT, the two (area and perimeter) and three (volume, surface area and SMI) dimensional changes and root canal transportation in mesial roots of mandibular molars with severe curvature, after the biomechanical procedures performed by four different NiTi, varying the kinematic type and preparation concept, the geometry and design of the instruments and the type of alloy treatment. In this way, the multi-instrument rotary system Protaper Next (PTN); the reciprocating single file system Reciproc (RC); the reciprocating single file system Reciproc Blue (RCB) and the multi-instrument rotary system TRUShape (TRS), were evaluated. Thirty-two lower molars with mesial root curvature angle of 25-50 ° and radius 4 mm were selected and scanned in a micro-CT 1176 (SkyScan, Kontich, Belgium) with 18 m isotropic resolution. After that, the images were reconstructed and analyzed to obtain the initial parameters (pre-instrumentation) of the area and perimeter, and three-dimensional volume, surface area, and SMI, besides of the root canal transportation by means of the centroid values. The specimens were distributed in experimental groups according to the instrumentation system used (n = 8), and after instrumentation, a new microtomographic analysis was performed following the initial standards described. The pre and post instrumentation data were tabulated and then the statistical analysis was performed using ANOVA and post Tukey test, with a significance level of 5%. The results showed that, regardless of the instrumentation system, changes in the two-dimensional and three-dimensional parameters, as well as the root canal transportation were noticed. No statistically significant differences (p> 0.05) were observed between the RC and RCB systems, as well as between the PTN and TRS systems in none of the analyzed parameters (bidimensional, three-dimensional and root canal transportation). In the cervical third, statistically significant differences (p <0.05) were found between the systems, with greater changes to RC and BCR, in relation to the PTN and TRS systems. In the apical third, there were no statistically significant differences (p> 0.05) between the systems, in relation to the parameters studied. It can be concluded that the systems analyzed in this study, independently of the number of instruments, the type of movement, the type of heat treatment of the alloys and the particular characteristics of each instrument, did not promote changes in the critical apical zone, and that the conicity promoted greater changes in the morphology of the canal, according to the evaluated parameters

<div>Pancreatic cancer is the present third leading cause of all cancer-associated deaths with a under 9% 5-year survival rate. Aggressive tumor progression and lack of early detection technique lead to the fact that most patients are diagnosed at terminal stage - pancreatic ductal adenocarcinoma (PDAC). Despite that numerous therapeutic approaches have been introduced, most options cannot advance to or fail at the clinical trials. It has been suggested that previous failure is due to insufficient understanding of PDAC tumor microenvironment (TME). Human PDAC is composed of severely fibrotic tissue (i.e., desmoplasia) that harbors a variety of malignant cells (e.g., pancreatic stellate cells, cancer-associated fibroblasts, macrophages, etc.), excessive extracellular matrices (ECM), as well as abnormal expression of growth factors, cytokines, and chemokines. Multiple cell-cell and cell-ECM interactions jointly result in a stiffened, hypoxic, and fluid pressure-elevated PDAC tissue. The resulting pancreatic TME not only physically hinders penetration of therapeutics, but also dynamically interacts with the residing cells, regulating their behaviors.</div><div><br></div><div>Increasing tumor tissue stiffness in PDAC is not only a passive outcome from desmoplasia, but an active environmental factor that promotes tumor survival, growth, and invasion. However, traditional in vitro cell culture systems such as two-dimensional (2D) culture plate and animal models are not ideal for mechanistic understanding of specific cell-matrix interactions. Therefore, dynamic hydrogels have been introduced as a category of advanced biomaterials that exhibit biomimetic, adaptable, and modularly tunable physiochemical property. Dynamic hydrogels can be precisely engineered to recapitulate a variety of aspects in TME, from which to investigate the role of dynamic tumor-stroma interaction in PDAC progression. The goal of this dissertation was to exploit synthetic polymers (i.e., poly(ethylene glycol) (PEG)) or natural ECM (i.e., gelatin and hyaluronic acid (HA)) as precursors to prepare the dynamic cancer-cell laden gels. The design utilized the orthogonal thiol-norbornene photopolymerization to prepare the primary homogenous xxvi</div><div><br></div><div>gel network. Next, through further functionalizing gel precursors with phenolic derivatives, enzymatic reaction (i.e., tyrosinase) or flavin mononucleotide (FMN)-mediated photochemistry could be harnessed to manipulate the dynamic changes of substrate mechanics. Experimentally, a computational model and the associated validation were presented to investigate the process of gel stiffening. Finally, these techniques were integrated to prepare cell-laden gels with spatial-temporally tunable properties that were instrumental in exploring the synergistic effects of dynamical matrix stiffening and presence of HA in promoting epithelial-mesenchymal transition (EMT) in PDAC cancer and stromal cells.</div>

The scale of the scholarly community complicates searches within scholarly databases, necessitating keywords to index the topics of any given work. As a result, an author’s choice in keywords affects the visibility of each publication; making the sum of these choices a key representation of the author’s academic profile. As such the underlying network of investigators are often viewed through the lens of their keyword networks. Current keyword networks connect publications only if they use the exact same keyword, meaning uncontrolled keyword choice prevents connections despite semantic similarity. Computational understanding of semantic similarity has already been achieved through the process of word embedding, which transforms words to numerical vectors with context-correlated values. The resulting vectors preserve semantic relations and can be analyzed mathematically. Here we develop a model that uses embedded keywords to construct a network which circumvents the limitations caused by uncontrolled vocabulary. The model pipeline begins with a set of faculty, the publications and keywords of which are retrieved by SCOPUS API. These keywords are processed and then embedded. This work develops a novel method of network construction that leverages the interdisciplinarity of each publication, resulting in a unique network construction for any given set of publications. Postconstruction the network is visualized and analyzed with topological data analysis (TDA). TDA is used to calculate the connectivity and the holes within the network, referred to as the zero and first homology. These homologies inform how each author connects and where publication data is sparse. This platform has successfully modelled collaborations within the biomedical department at Purdue University and provides insight into potential future collaborations.

<div>The eradication of yaws a neglected tropical disease caused by Treponema pallidum subsp. pertenue, which affects children living in very deprived hard to reach rural communities is constrained by the lack of rapid, accurate diagnosis. I sought to develop a molecular point-of-care test for the diagnosis of yaws. A Loop-mediated isothermal amplification (LAMP) assay with primers targeting the conserved gene, tp0967, with visual detection by lateral flow test strip was developed and optimized. The limit of detection was evaluated while 63 samples from clinical cases of yaws and 5 samples with PCR-confirmed syphilis were used to determine the sensitivity and specificity of the assay compared to the current molecular testing protocol. Reagents were dried in tubes and tested up to 14 days. The developed LAMP assay was found to be optimal when run at 65oC in a water bath for 30 minutes. The limit of detection was 2.7*104 DNA copies/ml. The sensitivity of the LAMP assay using unextracted and DNA extracted samples were 0.67 and 1.00 respectively. None of the syphilis samples tested positive in any of the assays. We show the development of a fast and sensitive LAMP assay for yaws detected by lateral flow test strip. Using extracted DNA, the assay sensitivity is at par with gold standard detection. The assay can be adapted to minimal sample processing required for in-field detection without DNA extraction.</div><div><br></div>

Introdução: As órteses são recursos terapêuticos auxiliares indicados para alívio da dor, melhora do padrão funcional ou aplicação de forças para correção de deformidades. Existe uma carência de estudos que analisem as alterações biomecânicas promovidas pelas órteses no padrão funcional do membro superior. O objetivo do presente estudo foi analisar os efeitos biomecânicos do ombro e do cotovelo com o uso de órteses funcionais em pacientes com disfunções decorrentes de traumas do sistema musculoesquelético. Métodos: O estudo analisou as alterações do padrão de movimento com o uso das órteses dinâmicas e estáticas por meio da análise cinemática e eletromiográfica do membro superior durante a realização de uma tarefa funcional padronizada, sendo que os controles serão os próprios pacientes. Os movimentos analisados foram flexão-extensão de ombro, abdução-adução de ombro, rotação interna-rotação externa de ombro, flexão-extensão de cotovelo, pronação-supinação. Na eletromiografia foi analisada a integral normalizada dos músculos trapézio superior, bíceps braquial e tríceps braquial. Além disso foi realizada dinamometria isométrica de preensão e pinças, bem como a aplicação do questionário QuickDASH sobre sintomatologia e funcionalidade. Foram incluídos 6 pacientes, maiores de 18 anos, com disfunções decorrentes de lesões nervosas periféricas e deformidades musculoesqueléticas decorrentes de artrite reumatóide, que tiveram indicação do uso de órtese. Resultados: embora as órteses estáticas sejam indicadas para correção de desvio ulnar e para bloqueio de garra mista, de acordo com os resultados deste estudo, não agregaram em termos de funcionalidade. Neste último modelo, um voluntário apresentou diferença clinicamente importante de 22,7 pontos, sinalizando piora da função na situação com órtese. Além disso, as órteses para bloqueio de garra mista demandaram maior recrutamento de trapézio superior e bíceps braquial. As órteses dinâmicas para lesão do nervo radial parecem favorecer a força de preensão estática, porém, promoveram compensações proximais durante a execução de tarefas dinâmicas, que envolveram elevação e deslocamento do membro superior, em termos de amplitude de movimento de abdução de ombro, flexão e pronação de cotovelo / Introduction: Orthoses are therapeutic resources that are indicated for pain relief, improvement of the functional pattern and / or to correct deformities. There is a lack of studies that analyze the biomechanical alterations promoted by the orthoses in the functional pattern of the upper limb. The aim of the present study was to analyze the biomechanical effects in shoulder and elbow promoted by orthoses in patients with upper extremity dysfunctions due to trauma of the musculoskeletal system. Methods: The range of motion and muscle activation was collected simultaneously during the performance of a standardized functional task with and witho no orthosis. The movements analyzed were shoulder flexion-extension, shoulder abduction-adduction, shoulder internal-external rotation, elbow flexion-extension, pronation-supination and the integrated electromyography signal of the upper trapezius, brachial bíceps and brachial triceps muscles were analyzed. In addition, isometric dynamometry of gripping and pinch, besides the application of the questionnaire QuickDASH about symptomatology and functionality. Were included six patients, older than 18 years, with peripheral nerve dysfunction and musculoskeletal deformities due to rheumatoid arthritis, who had indication of the use of orthosis. Results: although the static orthosis are indicated for correction of ulnar deviation and MCP extension-blocking, according to the results of this study, they did not add in terms of functionality. MCP extension-bloking orthosis promoted a clinically important difference of 22,7 points, suggesting worsing of the funtion. In addition, this model demanded greater proximal muscular recruitment of upper trapezius and brachial biceps. Dynamic orthoses for radial nerve injury seem to favor static grip strength, but they promoted proximal compensations during the execution of dynamic tasks, that involved elevation and displacement of the upper limb in terms of shoulder abduction, flexion and pronation of elbow

Atualmente, a avaliação das propriedades biomecânicas da córnea vem sendo considerada um parâmetro importante a ser determinado, uma vez que está relacionado a diversos procedimentos (diagnósticos e cirúrgicos) e oftalmopatias. Devido à complexa disposição de suas lamelas, o estroma corneal é considerado a camada que exerce maior influência sobre as propriedades elásticas da córnea. A busca por modelos experimentais no estudo das propriedades biomecânicas da córnea têm aumentado ultimamente, devido à dificuldade em se obter amostras de córnea humana para fins científicos. Logo, estudos comparativos entre a córnea humana e a suína vêm sendo desenvolvidos, e algumas similaridades foram identificadas entre estas duas espécies. O presente estudo tem como objetivo avaliar as propriedades biomecânicas de diferentes regiões da córnea suína por meio da microscopia da força atômica. Dezesseis bulbos oculares não escaldados, de oito animais da espécie suína, foram adquiridos em frigorífico local. Animais de diferentes raças, faixas de peso e idade foram utilizados neste estudo. Bulbos oculares frescos foram submetidos ao debridamento da camada epitelial da córnea, sendo posteriormente imersos em solução de dextran a 25%. Mensurações da paquimetria corneal em regiões central, superior, inferior, nasal e temporal foram realizadas em cada etapa do preparo das amostras. Após 24 horas submersas em solução de dextran, as córneas foram excisadas em fragmentos de aproximadamente 3 x 3 mm, conforme as regiões acima descritas. Tais fragmentos foram submetidos à avaliação pelo microscópio de força atômica, imersos em solução de dextran a 25%. Os valores do módulo de Young para cada fragmento foram obtidos com base no modelo de elasticidade de Hertz. O armazenamento de amostras de córnea em solução de dextran preveniu a hidratação excessiva destas, mantendo a paquimetria dentro dos valores considerados normais. Tanto a paquimetria quanto o módulo de elasticidade corneais não variaram dentre as regiões central, superior, inferior, nasal e temporal da córnea. A espessura e a elasticidade da córnea não diferiram frente à comparação de olhos contralaterais. Devido à facilidade de aquisição e aos resultados obtidos, a córnea suína pode ser empregada como modelo experimental na avaliação das propriedades biomecânicas corneais. / Currently, the assessment of corneal biomechanical properties has been considered an important parameter to be determined, since it is related to several procedures (diagnostic and surgical) and ocular diseases. Due to the complex arrangement of its lamellae, the corneal stroma is considered the layer that exert more influence on the elastic properties of the cornea. The demand for experimental models to study the biomechanical properties of the cornea has recently increased due to the difficulty in obtaining samples of human cornea for scientific purposes. Therefore, comparative studies between human and porcine cornea have been developed, and some similarities were identified between these two species. This study aims to evaluate the biomechanical properties of different regions of the porcine cornea using atomic force microscopy. Sixteen eyes, enucleated from eight animals, were purchased at a local slaughterhouse. Animals of different breeds, age and weight ranges were used in this study. Fresh eyeballs underwent debridement of the corneal epithelial layer, and subsequently immersed in 25% dextran solution. Measurements of corneal pachymetry in the central, superior, inferior, nasal, and temporal regions were performed at each stage of sample preparation. After 24 hours submerged in dextran solution, the corneas were excised into fragments of approximately 3 x 3 mm, according to the regions described above. These fragments were analysed by atomic force microscope immersed in 25% dextran solution. The values of Young modulus for each fragment were obtained from the elasticity model of Hertz. The storage of samples in dextran solution prevented their excessive hydration, keeping the pachymetry values within normal limits. Both corneal thickness and elastic modulus did not vary among the central, superior, inferior, nasal and temporal regions of the cornea. The thickness and elasticity of the cornea did not differ between right and left eyes. Due to the facility of acquisition and the results obtained, porcine cornea can be used as experimental model for assessment of corneal biomechanical properties.

O ser humano locomove-se utilizando-se do complexo sistema neuro-músculo-esquelético, o que lhe confere qualidade de vida. Partes do sistema esquelético são passíveis de tratamento ou mesmo de substituição pelo emprego de materiais estranhos ao corpo humano mas que provocam pequena reação biológica e necessitam ser dimensionados de modo a suportar toda tensão resultante do movimento humano. O objetivo deste trabalho foi desenvolver uma máquina de ensaio cíclico para testes biomecânicos, de implantes utilizados nas cirurgias de reconstrução ósteo-articular, utilizando tecnologia nacional. A máquina possui um sistema de acionamento por meio de um motor trifásico de 2 HP, 1800 rpm; um sistema de transmissão de cargas cíclicas utilizando um eixo excêntrico, que aciona um pistão, que promove o movimento de duas alavancas que transmitem a carga para os componentes a serem ensaiados. Há um inversor de freqüência para controle do número de ciclos do motor, um reservatório de soro fisiológico com um sistema que mantém o soro aquecido entre 36 e 38 ºC, e uma bomba hidráulica submersa que mantém o soro em constante movimentação. Foi feito um teste cíclico de fadiga de componente femoral de artroplastia de quadril, com torção, seguindo determinações das normas ISO 7206/89, parte 4 e ASTM F 1612/95, e utilizada para o teste a Prótese Femoral Cimentada Modelo Alpha ® da empresa Baumer ®, haste polida de 150 mm e off-set de 37,5 mm. Também foi feito um ensaio para verificação de trincas seguindo determinações da Norma ABNT NBR ISO 9583/1997. Durante as 139 horas previstas para o teste de fadiga do componente femoral, a máquina de ensaio não apresentou problemas mecânicos, demonstrando eficiência e o êxito na confecção de uma máquina de ensaios cíclicos para testes biomecânicos / The human being locomotes using the complex neuro-muscle-skeletal system, what confers him life quality. Parts of the skeletal system can submit to treatment or even to the substitution for the employment of strange materials to the human body but that provoke small biological reaction and they need to be projected in way to support every resulting tension of the human movement. The objective of this work was to develop a machine of cyclic trial for biomechanical tests using national technology. The machine has an activation system by means of a triphasic motor of 2 HP, 1800 rpm; a system of transmission of cyclic loads using an eccentric axis, that activates a piston, that promotes the movement of two levers that transmit the load for the components at be tested. There is a frequency inverter for control of the number of cycles of the motor, a reservoir of physiologic serum with a system that maintains the serum heated up to 36-38 ºC, and a submerged hydraulic bomb that maintains the serum in constant movement. It was made a cyclic test of fatigue of femoral component of hip arthroplasty, with torsion, following determinations of the norms ISO 7206/89, part 4 and ASTM F 1612/95, and used for the test the Prosthesis Femoral Cemented Model Alpha ® of the company Baumer ®, polished stem of 150 mm and off-set of 37,5 mm. It was also made a trial for verification of cracks following determinations of the norm ABNT NBR ISO 9583/1997. During the 139 hours foreseen for the test of fatigue of the femoral component, the trial machine didn’t present mechanical problems, demonstrating efficiency and the success in the production of a machine of cyclic trials for biomechanical tests

O presente estudo objetivou comparar biomecanicamente, por meio do ensaio de compressão excêntrica, a resistência dos implantes Clamp and Rod Internal Fixation (CRIF) 5,0 mm versus placa de reconstrução 3,5 mm na fixação de fratura distais de fêmur de cão. Tais implantes foram subdividos em dois grupos, denominados grupo CRIF (GC) e grupo placa (GC). Foram utilizados 22 fêmures de 10 cadáveres de cão entre 2 e 7 anos de idade e peso corporal entre 20 e 40 kg, que foram distribuídos aleatoriamente a serem testados ambos os implantes em cada um dos membros dos pares. Para realização dos testes, foi simulado uma fratura distal nos corpos de prova, através de uma osteotomia de até 0,5 cm, realizada por meio de serra oscilatória, imediatamente proximal ao início da tróclea. Os implantes foram fixados segundo os padrões AOSIF, lateralmente ao fêmur, sendo utilizados três parafusos distais e cinco proximais ao foco de fratura. Foi utilizado o programa de computador PMI para calcular o ponto máximo de resistência antes da falha e avaliadas as variáveis força máxima, deformação máxima real, rigidez, força intermediária e deformação intermediária real. Não foram encontradas diferenças estatisticamente significativas entre os GC e GP quantos as variáveis avaliadas / This study aims to compare the biomechanical properties, through eccentric compression test, of the resistance of the 5.0 mm Clamp and Rod Internal Fixation Implants (CRIF) and 3.5 mm reconstruction plate in fixing dog femur distal fracture. Such implants were subdivided into two groups, called CRIF Group (CG) and plate group (CG). It was used 22 femurs from 11 dog cadavers with age between 2 and 7 years old and body weight between 20 and 40 kg, which was randomly assigned to test both implants in each member of the pair. A distal fracture in the specimens with a gap of 0.5 cm osteotomy, it was simulated to perform the test, performed by the oscillating saw, just proximal to the beginning of the trochlea. Bound the distance from the gap to the distal femur limit was equivalent to the distance between the femoral condyles. The implants were fixed by the standards AO / SIF, laterally to the femur, being used three distal screws and five proximal to the fracture site. The bone was placed longitudinally, and the femoral neck coupled to a concave surface simulating an acetabular device. PMI computer program was used to calculate the maximum point of resistance before failure and evaluated the variables maximum strength, real maximum deformation, stiffness, intermediate strength and real intermediate deformation. No statistically significant differences were found between the GC and GP as the variables evaluated

O domínio da locomoção é essencial para a execução adequada de diferentes atividades da vida diária. Atualmente, utiliza-se de vários instrumentos de treinamento para o retorno às atividades funcionais, como a esteira rolante e o elíptico. O problema desta pesquisa está baseado na pergunta: Qual é o padrão de ativação dos músculos do membro durante o exercício no elíptico? O objetivo principal é analisar e descrever as características biomecânicas da aceleração e da atividade eletromiográfica do andar em um elíptico. Participaram 42 adultos divididos em três grupos: grupo adulto jovem, constituído por 20 adultos jovens, grupo adulto idoso, constituído por 12 adultos idosos, ambos praticantes de atividade física regular e sem lesões ou problemas no aparelho locomotor, e grupo de adultos pós acidente vascular encefálico, constituído por 10 indivíduos. O questionário internacional de atividade física e os testes para a avaliação qualitativa da marcha, o teste de categoria de ambulação funcional e teste de equilíbrio em pé foram aplicados. Foram utilizados um acelerômetro tridimensional e um eletromiógrafo de superfície com 16 canais, além de uma esteira ergométrica e um elíptico. Após a familiarização com os equipamentos, os sujeitos andaram no elíptico e na esteira enquanto que a atividade miolétrica e a aceleração tibial foram coletadas. O tempo de coleta foi de 20s e a frequência de aquisição foi 2kHz. As curvas do envoltório linear foram geradas e normalizadas pela base do tempo. Resultados: A amplitude da ativação muscular foi maior durante a marcha na esteira, na fase de propulsão, no grupo de pessoas com AVE e idosos e nos músculos tibial anterior e bíceps femoral (p<0,0001). A menor ativação muscular foi observada no músculo reto abdominal, no grupo de adultos jovens, na fase pré-balanço (p<0,0001). Na análise qualitativa a aceleração da tíbia foi menor para o equipamento elíptico em comparação com a esteira. Os resultados favorecem a indicação do elíptico para o processo de recuperação da locomoção de pessoas com dificuldade para andar com limitações neurológicas ou ortopédicas / The achievement of the locomotion is essential for the adequate performance of different daily life activities. Several training instruments for the return to the functional activities exist, such as the treadmill and the elliptical. The research problem is: What is the lower limb muscle activation pattern during exercising in an elliptical trainer? The aim of this study is to analyze and describe the biomechanical characteristics of the acceleration and myoeletrical activity during walking in an elliptical trainer. The participants were 42 adults divided into three groups: young adult group (n=20), old adult group (n=12), both physically active and without any chronic pain or orthopedic conditions that could alter gait patterning, and chronic stroke adults (n=10). The international questionnaire of physical activity, the gait functional test and balance test were applied. We used one accelerometer and 16-channels electromyography system, a treadmill and an elliptical trainer. They walked on the elliptical and on the treadmill while the myoelectrical activity of 8 muscles and the tibial acceleration were recorded. The recording time was 20 s and sampling frequency was 2 kHz. The ensemble average was calculated for each variable. Results: The muscle activation was the highest at the treadmill, for propulsion phase, for the people with stroke and elderly and for the muscles Tibialis Anterior and Biceps Femoris (p<0.0001). The smallest muscle activity was observed on the Rectus Abdominus muscle, for the young adults, for pre contact phase (p<0.0001). The tibial acceleration was smaller for the elliptical than the treadmill. The results support the use of the elliptical for the rehabilitation of gait impairments related to neurological or orthopedic limitations