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Arm regeneration in two populations of Ophionereis reticulata (Echinodermata, Ophiuroidea)

YOKOYAMA, Leonardo Q.; AMARAL, Antonia Cecilia Z.
Fonte: FUNDACAO ZOOBOTANICA RIO GRANDE SUL, MUSEU CIENCIAS NATURAIS Publicador: FUNDACAO ZOOBOTANICA RIO GRANDE SUL, MUSEU CIENCIAS NATURAIS
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.66%
This study compared the arm regeneration frequencies in two different populations of Ophionereis reticulata (Say, 1825) in Sao Sebastiao, Southeast Brazil and observed arm regeneration between age classes (juvenile and adults) and sexes (male and female). From the 1,170 individuals sampled, 1,089 (92.2%) showed signs of arm regeneration. The relative frequencies of regenerating arms in the two areas were not different (Baleeiro Isthmus: 91.3% and Grande Beach: 99.5%). Both areas also presented similar values for the number of arms regenerating/individual and in the frequency of regenerating individuals. The major part of the regenerating scars was concentrated in the distal portion of the arm. Sub-lethal predation is most likely the cause to the high rates of arm regeneration in O. reticulata. There was no significant differences in the regeneration rates between females (3.57 +/- 1.36 arms regenerating/individual) and males (3.47 +/- 1.42).; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundo de Apoio Ao Ensino, a Pesquisa e a Extensao (FAEPEX-UNICAMP); Fundo de Apoio ao Ensino, a Pesquisa e a Extensao (FAEPEX/UNICAMP)

Antimicrobial activity of two techniques for arm skin disinfection of blood donors in Brazil

Celere, M. S.; Ferreira, O.; Ubiali, E. M. A.; Juliao, F. C.; Fernandes, A. F. T.; de Andrade, D.; Segura-Munoz, S. I.
Fonte: WILEY-BLACKWELL; MALDEN Publicador: WILEY-BLACKWELL; MALDEN
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.62%
Objective: Evaluation of the antimicrobial effect of skin disinfection techniques is essential to avoid the transmission of infectious agents during blood transfusion. The aim of this study was to examine the effectiveness of two methods of arm skin disinfection used in blood donors at a Hemotherapy Center in Brazil that represents an important centre for distributing haemocomponents to many cities in the country. Methods: Two skin disinfection techniques in 50 blood donors were evaluated. For the first arm, 10% povidone-iodine/two-stage technique was used. On the opposite arm, 0.5% chlorhexidine digluconate alcohol solution/one-stage technique was used. The swabs were seeded on three culture media: blood agar, mannitol salt agar and Mac Conkey agar. Automated bacterial classification based on biochemical tests/specific substrates was performed. Donor characteristics were collected using the computerised system of the Hemotherapy Center. Results: We found that microbial reduction was significantly higher for 10% povidone-iodine technique (98.57-98.87%) when compared with 0.5% chlorhexidine technique (94.38-95.06%). The species Leuconostoc mesenteroides and Staphylococcus hominis showed resistance to both disinfection techniques. We did not find statistically significant relationships between donor characteristics and microbial reduction. Conclusions: Arm skin disinfection with 10% povidone-iodine produced better antimicrobial activity. We must acknowledge that 10% povidone-iodine technique has the limitation of being a two-stage method. However...

"Comparação anatômica entre o retalho perfurante ântero-lateral da coxa e os retalhos cutâneos paraescapular e lateral do braço" ; Anatomical comparison of the anterolateral thigh perforator flap and the parascapular and lateral arm skin flaps

Busnardo, Fabio de Freitas
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/09/2006 PT
Relevância na Pesquisa
36.66%
A descrição de retalhos cutâneos pediculados em ramos perfurantes musculares é recente. O retalho ântero-lateral da coxa é vascularizado por vasos perfurantes musculares do ramo descendente da artéria circunflexa femoral lateral. Trata-se de retalho de pouca espessura, pedículo vascular longo e calibroso e baixa morbidade de área doadora. Entretanto, a dissecção do trajeto intramuscular de seu pedículo é tecnicamente difícil. Sua indicação é por vezes questionada por tratar-se de retalho de características semelhantes a outros vascularizados por artérias cutâneas diretas ou septocutâneas. Estes têm menor variação anatômica e dissecção mais simples. O presente estudo avaliou as características anatômicas do retalho ântero-lateral da coxa, através de dissecção em cadáveres frescos, comparando-as com as do retalho paraescapular e lateral do braço. Foram dissecados 60 retalhos (20 retalhos ântero-laterais da coxa, 20 paraescapulares e 20 retalhos laterais do braço) em 20 cadáveres frescos, não formolizados, com menos de 24 horas após o óbito. Todos os retalhos tiveram os seguintes parâmetros avaliados: comprimento do pedículo vascular, espessura do retalho, diâmetro do pedículo vascular arterial e venoso. Além disso...

Estudo anatômico das dimensões e do padrão vascular do retalho lateral do braço ampliado distalmente ao epicôndilo lateral; Anatomic study of the dimensions and the vascular pattern of distal part to lateral epicondyle of the extended lateral arm flap

Gonçalves, Renato Ribeiro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 28/04/2003 PT
Relevância na Pesquisa
36.62%
Foram realizadas dissecções anatômicas de 45 membros superiores de cadáveres, com o objetivo de avaliar as dimensões e o padrão vascular da porção distal ao epicôndilo lateral do retalho lateral do braço. Todos os casos deste estudo eram do sexo masculino, com idade superior a 21 anos. Os casos foram divididos em grupos A, B, e C e submetidos a injeção de contraste diretamente na artéria colateral radial posterior. Nos cadáveres do Grupo A, foi injetado contraste a base de azul de metileno e serviu para avaliar o maior comprimento e largura de pele corada pelo contraste, tendo como local para início das medidas o epicôndilo lateral do úmero. No Grupo B foi utilizada a mesma metodologia do Grupo A, sendo acrescentado para cada cadáver em estudo, uma ficha com os dados antropométricos e serviu para avaliar a extensão de pele corada pelo contraste e correlacioná-la com os dados antropométricos individuais. Nos cadáveres do Grupo C foi utilizado contraste a base de látex e serviu para avaliar o padrão vascular da artéria colateral radial posterior encontrado distalmente ao epicôndilo lateral. Em todos os casos a pele foi corada pelo contraste distalmente ao epicôndilo lateral, com o comprimento variando de 4 cm a 12 cm...

Assessment of anaerobic power of swimmers: the correlation of laboratory tests on an arm ergometer with field tests in a swimming fool

Guglielmo, LGA; Denadai, B. S.
Fonte: Allen Press Inc Publicador: Allen Press Inc
Tipo: Artigo de Revista Científica Formato: 395-398
ENG
Relevância na Pesquisa
36.62%
The aim of this study was to verify the correlation between the Wingate arm crank test outputs (peak power, mean power, and fatigue index), obtained on a specific ergometer, and the performance in crawl stroke swim sprints of 14, 25, 50, and 400 m. The experiment was conducted with 9 healthy male volunteers (18.1 +/- 2.2 years of age; 172 +/- 0.04 cm; 67.7 +/- 5.92 kg and 15.7 +/- 4.57% body fat). on determined days, all individuals were submitted to the Wingate arm crank test and crawl freestyle sprints of 14, 25, 50, and 400 m as they were timed with a stopwatch. The peak power, the mean power, and the fatigue index, which were obtained during the Wingate arm crank test, were not significantly correlated with the maximum swim velocities during the crawl free-style tests of 14 (r = 0.40; r = 0.64; r = 0.11), 25 (r = 0.28; r = 0.39; r = -0.27), 50 (r = 0.03; r = 0.09; r = -0.31), and 400 (r = -0.52; r = -0.37; r = -0.65) m respectively. Thus, it is possible to conclude that the Wingate arm crank test is not suitable to assess the anaerobic power of swimmers under the described experimental conditions.

Arm regeneration in two populations of Ophionereis reticulata (Echinodermata, Ophiuroidea)

YOKOYAMA, Leonardo Q.; AMARAL, Antonia Cecilia Z.
Fonte: FUNDACAO ZOOBOTANICA RIO GRANDE SUL, MUSEU CIENCIAS NATURAIS Publicador: FUNDACAO ZOOBOTANICA RIO GRANDE SUL, MUSEU CIENCIAS NATURAIS
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.66%
This study compared the arm regeneration frequencies in two different populations of Ophionereis reticulata (Say, 1825) in Sao Sebastiao, Southeast Brazil and observed arm regeneration between age classes (juvenile and adults) and sexes (male and female). From the 1,170 individuals sampled, 1,089 (92.2%) showed signs of arm regeneration. The relative frequencies of regenerating arms in the two areas were not different (Baleeiro Isthmus: 91.3% and Grande Beach: 99.5%). Both areas also presented similar values for the number of arms regenerating/individual and in the frequency of regenerating individuals. The major part of the regenerating scars was concentrated in the distal portion of the arm. Sub-lethal predation is most likely the cause to the high rates of arm regeneration in O. reticulata. There was no significant differences in the regeneration rates between females (3.57 +/- 1.36 arms regenerating/individual) and males (3.47 +/- 1.42).; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Continuous evaluation of the stiffness of stabilized soils since compaction: enhancements to the EMM-ARM methodology; Avaliação contínua da deformabilidade de solos estabilizados desde a compactação: refinamentos à metodologia EMM-ARM

Vieira, Luís Miguel Rios
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Trabalho de Conclusão de Curso
Publicado em //2014 ENG
Relevância na Pesquisa
36.77%
Dissertação de mestrado integrado em Civil Engineering; The stabilization of soils has been used for the improvement of its characteristics to meet required performances. Binders are widely used for the stabilization process, and thereby the soil suffers a hardening process during which its mechanical properties are improved, namely its stiffness. Monitoring the stiffness evolution over the hardening time can reveal important information for quality control, and early identification of potential problems. The EMM-ARM (Elasticity Modulus Measurement through Ambient Response Method) has been applied to stabilized soils in pursuit of a robust method that actually allows continuous measurement of the stiffness of a stabilized soil since very early ages. EMMARM is based on the identification of the resonance frequency of a composite beam that comprises the tested material, over the curing time and allows inferring the E-modulus of the stabilized time through the dynamic equation of motion of the beam. This technique has been used on stabilized soils with success. However, the technique still lacked a sampling method that allowed retrieving representative samples from in-situ layers. This dissertation aimed to contribute for the development of the EMM-ARM technique namely in developing a sampling procedure that can be applied on practical conditions. Therefore...

Control and Function of Arm Swing in Human Walking and Running

Pontzer, Herman; Lieberman, Daniel Eric; Holloway, John H. III; Raichlen, David A.
Fonte: The Company of Biologists Publicador: The Company of Biologists
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.73%
We investigated the control and function of arm swing in human walking and running to test the hypothesis that the arms act as passive mass dampers powered by movement of the lower body, rather than being actively driven by the shoulder muscles. We measured locomotor cost, deltoid muscle activity and kinematics in 10 healthy adult subjects while walking and running on a treadmill in three experimental conditions: control; no arms (arms folded across the chest); and arm weights (weights worn at the elbow). Decreasing and increasing the moment of inertia of the upper body in no arms and arm weights conditions, respectively, had corresponding effects on head yaw and on the phase differences between shoulder and pelvis rotation, consistent with the view of arms as mass dampers. Angular acceleration of the shoulders and arm increased with torsion of the trunk and shoulder, respectively, but angular acceleration of the shoulders was not inversely related to angular acceleration of the pelvis or arm. Restricting arm swing in no arms trials had no effect on locomotor cost. Anterior and posterior portions of the deltoid contracted simultaneously rather than firing alternately to drive the arm. These results support a passive arm swing hypothesis for upper body movement during human walking and running...

The effect of arm weight support on upper limb muscle synergies during reaching movements

Coscia, Martina; Cheung, Vincent CK; Tropea, Peppino; Koenig, Alexander; Monaco, Vito; Bennis, Caoimhe; Micera, Silvestro; Bonato, Paolo
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.81%
Background: Compensating for the effect of gravity by providing arm-weight support (WS) is a technique often utilized in the rehabilitation of patients with neurological conditions such as stroke to facilitate the performance of arm movements during therapy. Although it has been shown that, in healthy subjects as well as in stroke survivors, the use of arm WS during the performance of reaching movements leads to a general reduction, as expected, in the level of activation of upper limb muscles, the effects of different levels of WS on the characteristics of the kinematics of motion and of the activity of upper limb muscles have not been thoroughly investigated before. Methods: In this study, we systematically assessed the characteristics of the kinematics of motion and of the activity of 14 upper limb muscles in a group of 9 healthy subjects who performed 3-D arm reaching movements while provided with different levels of arm WS. We studied the hand trajectory and the trunk, shoulder, and elbow joint angular displacement trajectories for different levels of arm WS. Besides, we analyzed the amplitude of the surface electromyographic (EMG) data collected from upper limb muscles and investigated patterns of coordination via the analysis of muscle synergies. Results: The characteristics of the kinematics of motion varied across WS conditions but did not show distinct trends with the level of arm WS. The level of activation of upper limb muscles generally decreased...

Arm vein as a last autogenous option for infrainguinal bypass surgery: It is worth the effort

Varcoe, R.; Chee, T.; Subramaniam, P.; Roach, D.; Benveniste, G.; Fitridge, R.
Fonte: W B Saunders Co Ltd Publicador: W B Saunders Co Ltd
Tipo: Artigo de Revista Científica
Publicado em //2007 EN
Relevância na Pesquisa
36.66%
Objectives: Considerable evidence exists for the use of arm vein conduit in lower limb bypass surgery. The use of arm vein in preference to synthetic conduit as a last autogenous option was assessed for patency and limb salvage outcomes. Materials and methods: A prospective database was interrogated and checked against TQEH operating theatre database to detect all infrainguinal arm vein bypasses performed between 1997 and 2005. Patency, limb salvage and survival data for 37 arm vein bypasses was calculated using the Kaplan-Meier survival estimate method. Results: There were no perioperative deaths. 30 day patency rates were 89% primary, 95% secondary and 95% limb salvage. 12 month patency rates were 56% primary, 79% secondary and 91% limb salvage. 5 year patency rates were 37% primary, 76% secondary and 91% limb salvage. There was no significant patency advantage for primary vs. “redo” grafts (p = 0.54), single vessel vs. spliced conduits (p = 0.33) or popliteal vs tibial outflow (p = 0.80). Patient survival rate was 92% and 65% at 1 and 5 years respectively. Conclusion: Lower limb bypasses using arm vein can be performed with favourable patency and limb salvage compared to synthetic conduits. However, secondary interventions are frequently required to maintain patency. We recommend a vigilant surveillance program for early identification of patency threatening disease.; R.L. Varcoe...

Long-term follow-up of last autogenous option arm vein bypass

Robinson, D.; Varcoe, R.; Chee, W.; Subramaniam, P.; Benveniste, G.; Fitridge, R.
Fonte: Blackwell Science Asia Publicador: Blackwell Science Asia
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
36.66%
BACKGROUND The superiority of autogenous conduits in infrainguinal bypass surgery is well established. At our institution, arm vein is utilized as the last autogenous option for infrainguinal bypass surgery. The aim of this study was to review the long-term outcomes of last autogenous option arm vein bypass. METHODS All infrainguinal arm vein bypasses performed between 1997 and 2005 by The Queen Elizabeth Hospital vascular surgeons were identified. Patency, reintervention, limb salvage and survival were calculated using the Kaplan–Meier survival estimate method. RESULTS Thirty-eight arm vein bypasses were performed in 35 patients. Eighty-nine per cent were performed for critical limb ischaemia. Median follow-up was 58 months (range 2–121). Twelve-month primary, assisted primary and secondary patency rates were 52%, 73% and 76%, respectively. Three-year primary, assisted primary and secondary patency rates were 32%, 61% and 63%, respectively. Five-year primary, assisted primary and secondary patency rates were 21%, 47% and 49%, respectively. Patency was superior in single compared with spliced vein grafts (P < 0.05). Limb salvage rates at 1, 3 and 5 years were 94%, 87% and 76%, respectively. Patient survival at 1, 3 and 5 years was 92%...

Portado de MaRTE OS a la arquitectura ARM; MaRTE OS port to ARM architecture

García Villaescusa, David
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Trabalho de Conclusão de Curso
SPA
Relevância na Pesquisa
36.71%
RESUMEN: Este proyecto, como su propio nombre indica, consiste en el portado de MaRTE OS a la arquitectura ARM. Para dicho portado se ha escogido una plataforma de desarrollo sobre la que comprobar, junto a un emulador, la funcionalidad del desarrollo. La plataforma seleccionada para este propósito es la polifacética Raspberry Pi. El portado debe de realizarse teniendo en cuenta que MaRTE OS es un sistema operativo de tiempo real estricto. Esto quiere decir que hay que tener especial atención con el reloj, las interrupciones del temporizador y el cambio de contexto. Se tiene en cuenta que en un futuro es muy posible que se requiera el portado de MaRTE OS a otras plataformas que comparten la arquitectura ARM, pero tienen ciertas diferencias respecto a la plataforma Raspberry Pi. Se pretende, por lo tanto, hacer su adaptación lo más sencilla posible. También hay que considerar que este no es el primer portado que se realiza de este sistema operativo y que est´a preparado para dicho fin. Es muy importante percatarse de las posibles mejoras que se pueden hacer al propio sistema operativo, el portado a esta plataforma puede destapar ciertas mejoras a realizar en un futuro. En este proyecto se desvelaría este proceso, descubriendo el más bajo nivel de la arquitectura ARM...

Unmanned systems: a lab-based robotic arm for grasping

Jacinto, Arturo, II
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
36.69%
Approved for public release; distribution is unlimited; This thesis implements the development of a Robotic Manipulation Laboratory to explore learning opportunities for various student experiments including the initial selection, startup and development of the Robotic arm and glove controller. The Robotic Manipulation Laboratory consists of a 6 Degree of Freedom robotic arm and a resistive glove controller that allows students to achieve hands-on understanding of the physics required to fabricate and maneuver a robotic arm. The Kinova JACO robotic arm was selected for its smooth operation, the ability to alter operational speed and open source programming examples. We chose a glove controller for ease of training and human-like efficiency. Testing on the JACO arm was completed. The JACO software was installed and verified for standalone operations within its range of motion. Tests on glove/arm interaction in the Robotic Operating System were completed and proved ineffective. Experiments with flex sensors on the glove for normal hand movements were completed and were successful.; ; Lieutenant, United States Navy

Comparison of volume displacement versus circumferential arm measurements for lymphoedema: Implications for the SNAC Trial

Tewari, N.; Gill, P.; Bochner, M.; Kollias, J.
Fonte: Blackwell Science Asia Publicador: Blackwell Science Asia
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
36.71%
Background: The Royal Australasian College of Surgeons Sentinel Node versus Axillary Clearance trial is a randomized controlled trial comparing sentinel node biopsy with axillary clearance in breast cancer patients. Primary study end-points include arm volume differences with time, which may indicate the development of lymphoedema. The RACS SNAC trial uses circumferential arm measurements in the estimation of arm volume. This study aimed to assess the accuracy of circumferential volume estimation in comparison with water displacement. Methods: Eighty-seven women attending the breast clinic at the Women's Health Centre, Royal Adelaide Hospital, were assessed by volumetric and circumferential arm measurements. Correlations between volume estimations and measurements were made, taking into account the width of measuring tape and body mass index. Results: There was a highly significant correlation between circumferential and volumetric arm measurements (Pearson's correlation coefficient = 0.92, P < 0.0001), especially when using the narrow measuring tape. Correlation was best in the overweight BMI group (Pearson's correlation coefficient = 0.94. P < 0.0001) and worst in the obese group (Pearson's correlation coefficient = 0.79, P < 0.0001) but all relationships were statistically significant. Conclusion: Using a narrow tape...

ROTATION ENCODING OF C-ARM FLUOROSCOPES WITH ACCELEROMETER

GRZEDA, VICTOR
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
36.71%
Accurate, practical, and affordable pose tracking on manually operated C-arm fluoroscopes is a major technical challenge. Conventional tracking methods, such as optical cameras and radiographic fiducials, are hampered by significant shortcomings. Optical cameras are delicate, costly, and have a complex system setup that is easily susceptible to camera obstruction in cluttered operating room. Radiographic fiducials occupy a significant portion of the fluoroscopic imaging space. Using fiducials also requires segmentation that limits clinical use. In this thesis, an alternative form of tracking is proposed to encode the rotational joints of manually operated C-arms using a tilt sensing accelerometer for tracking the C-arm rotational pose. The technique is evaluated by affixing an accelerometer to a full-scale C-arm where a webcam is used as a substitute for X-ray imaging. Ground truth C-arm rotational poses were obtained from the webcam by tracking a checkerboard plate. From these rotational poses, a series of angle and structural correction equations were formulated that can properly relate the accelerometer angle readings to the C-arm rotational pose in real-time and compensate for systematic structural C-arm deformations...

Do single-arm trials have a role in drug development plans incorporating randomised trials?

Grayling, Michael J.; Mander, Adrian P.
Fonte: Wiley Publicador: Wiley
Tipo: Article; published version
EN
Relevância na Pesquisa
36.81%
This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/pst.1726; Often, single-arm trials are used in phase II to gather the first evidence of an oncological drug?s efficacy; with drug activity determined through tumour response using the RECIST criterion. Provided the null hypothesis of ?insufficient drug activity? is rejected, the next step could be a randomised two-arm trial. However, single-arm trials may provide a biased treatment effect due to patient selection, and thus this development plan may not be an efficient use of resources. Therefore, we compare the performance of development plans consisting of single-arm trials followed by randomised two-arm trials, to stand-alone single-stage or group sequential randomised two-arm trials. Through this we are able to investigate the utility of single-arm trials, and determine the most efficient drug development plans, setting our work in the context of a published single-arm non-small-cell lung cancer trial. Reference priors, reflecting the opinions of ?sceptical? and ?enthusiastic? investigators, are used to quantify and guide the suitability of single-arm trials in this setting. We observe that the explored development plans incorporating single-arm trials are often non-optimal. Moreover...

MID ARM CIRCUMFERENCE IN PREGNANT WOMEN AND ITS RELATION TO OTHER MATERNAL ANTHROPOMETRIC INDICATORS; EL PERIMENTO BRAQUIAL EN LA MUJER GESTANTE, Y SU RELACIÓN CON OTRAS MEDIDAS ANTROPOMÉTRICAS MATERNAS; EL PERIMENTO BRAQUIAL EN LA MUJER GESTANTE, Y SU RELACIÓN CON OTRAS MEDIDAS ANTROPOMÉTRICAS MATERNAS

Ricalde, Anamaria E.; Siqueira, Arnaldo A. F. de
Fonte: Universidade de São Paulo. Faculdade de Saúde Pública Publicador: Universidade de São Paulo. Faculdade de Saúde Pública
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 19/12/1996 SPA
Relevância na Pesquisa
36.73%
; Weight, height, arm circumference and uterine height during pregnancy were compared in a cross sectional study with two hundred pregnant women, in order to determine therelationship between maternal arm circumference and other anthropometric indicators, and to determine patterns of changes of arm circumference during pregnancy. During the study, maternal arm circumference remained stable in the three trimesters of pregnancy. An analysis of arm circumference means showed no statistically significant diferences (P>0,05).Pearson correlation analysis showed that arm circumference was strongly correlated with weight at anytime during pregnancy; on the other hand, it was not correlated with gestational age, maternal height or uterine height at different trimesters. This implies that a woman’s arm circumference can be measured at any point in pregnancy to estimate pre-pregnancy weight. These findings, together with the practical advantages of using maternal arrn circu~ference, considerably strengthen the argument for using arm circumference for nutritional monitoring of pregnant women.; Con el objetivo de determinar las variaciones dei perimetro braquial durante ei embarazo y verificar la relación entre este indicador y otras medidas antropométricas...

Influência da posição do braço na relação EMG-força em músculos do braço; Influence of arm position on the EMG-force relationship in arm muscles

Oliveira, Anamaria Siriani de; Tucci, Helga Tatiana; Verri, Edson Donizetti; Vitti, Mathias; Regalo, Simone Cecílio Hallak
Fonte: Universidade de São Paulo. Faculdade de Medicina Publicador: Universidade de São Paulo. Faculdade de Medicina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/01/2008 POR
Relevância na Pesquisa
36.77%
A relação entre a amplitude do sinal eletromiográfico e a força muscular (EMG-força) tem sido tomada como medida indireta da força muscular. Este estudo, em 18 voluntárias saudáveis e destras, visou avaliar a influência da posição do braço na relação EMG-força em músculos do braço em três tarefas - flexão do braço (FB), abdução do braço (AB) e neutra do braço (NB) - enquanto se tomavam ambas as medidas: uma célula de carga foi acoplada ao conversor do eletromiógrafo para registrar simultaneamente força e sinal eletromiográfico. Foram analisados os sinais dos músculos bíceps braquial, braquiorradial e tríceps braquial, e estimada a força de flexão e de extensão do braço nas diferentes tarefas. A relação entre esses conjuntos de valores foi analisada estatisticamente, verificando se havia correlação entre força e sinal eletromiográfico. Os resultados mostraram não haver tal correlação nas tarefas avaliadas. A posição do braço não influenciou a relação EMG-força dos músculos avaliados, com exceção do tríceps braquial, cuja atividade eletromiográfica foi maior durante a tarefa NB. Conclui-se que, em isometria, as tarefas podem ser empregadas para ativar o bíceps braquial e o braquiorradial; a tarefa NB é a mais indicada para ativar o tríceps braquial.; The relationship between myoelectric signal amplitude and muscle strength (EMG-force) has been used as an indirect measure of muscle strength. The aim of this study...

IMPROVED CONTROL FOR AN ARTIFICIAL ARM

Jones, Ben; Kyberd, Peter
Fonte: Myoelectric Symposium Publicador: Myoelectric Symposium
Tipo: Artigo de Revista Científica Formato: 189623 bytes; application/pdf
Publicado em //2005 EN_US
Relevância na Pesquisa
36.71%
Successful control of multi-degree of freedom upper limb prostheses generally uses some form of sequential instruction. This is because simultaneous control of multiple inputs requires a considerable concentration to be operated effectively. In contrast, the natural arm is controlled in a parallel manner with a high level of subconscious control. Such control uses feedback, the person is rarely conscious of the feedback information, and most of the control is automatic. Attempts to achieve similar control with a prosthesis would requires a wide bandwidth feedback channel to the controller. This is currently impractical if the controller of a multiple degree of freedom arm is the wearer, because only very low frequency feedback is achievable. The Southampton Arm control philosophy avoids this bottleneck by keeping the low level control within the prosthesis and leaves low bandwidth and strategic control to the operator [1]. This study describes the development of a control system for an artificial arm based on this concept. A joystick was used to input control signals via a harness at the shoulder, allowing a user to manipulate the arm with small movements of their acromium. A co-ordinate control strategy (inverse kinematics or IK) was implemented allowing both the shoulder and elbow joints of the arm to move simultaneously giving a smooth...

MAXFAS: a mobile arm exoskeleton for firearm aim stabilization

Baechle, Daniel
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
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Agrawal, Sunil K.; Accurately aiming and firing a pistol requires a steady hand. While many devices can steady a shooter's arm or hand by restricting movement or degrees of freedom, few devices actively reduce involuntary tremors while allowing larger voluntary aiming movements. This paper details the design, fabrication, and experimental evaluation of an arm exoskeleton that can actively damp arm tremors while allowing voluntary aiming movements. The MAXFAS (Mobile Arm eXoskeleton for Firearm Aim Stabilization) device allows five degrees of freedom, controlling four degrees of freedom using thin steel cables. The cable-driven architecture allows the control motors to be mounted away from the arm, resulting in device that adds very little weight and inertia to the arm. The cables attach to braces that are mounted on the forearm and upper arm. Weight of MAXFAS is further reduced compared to conventional arm exoskeletons through the careful design and manufacture of the braces using stiff, lightweight carbon fiber composites. The initial design called for tremorous movement to be filtered out from voluntary motion, and an adaptive algorithm to provide a tremor-cancelling signal to the cable control motors. Experiments described in this paper involved a control method which used the motors to only actively allow voluntary motion...