ABSTRACT
This study aimed to develop a Walking Pattern Evaluation System during Hypogravity Simulation (SAMSH), which included the adaptation of a body suspension device, the instrumentation of a treadmill and the development of a virtual environment. SAMSH was developed using one subject. Kinematic analyses were performed whilst one individual was walking on the treadmill during body weight reduction simulating the gravitational forces of the Moon (reduction of 60%) and Mars (reduction of 30%) with and without virtual reality glasses (Head Mounted Display, HMD). The walking pattern was evaluated by means of knee and ankle electrogoniometers, foot switches placed on the front and back part of the plantar region, and five video cameras. Results showed that the body weight reduction during Moon simulation alter the walking pattern, including the increase in step time, contact time, step length and aerial time, and the decrease of walking cadence time (steps per minute). The findings of this study also suggested that hypogravity simulation reduces walking effort. The utilization of the HMD allowed the evaluation of the head position three-dimensionally during hypogravity simulation. The virtual environment reduced postural balance, due to the absence of visual input, which was evidenced by a protective extension reaction.
Subject(s)
Engineering/methods , Gait , Walking , Algorithms , Biomechanical Phenomena , Body Weight , Computer Simulation , Earth, Planet , Equipment Design , Humans , Hypogravity , Mars , Models, Theoretical , Moon , Postural Balance , SpacecraftABSTRACT
A headward fluid shift occurs during microgravity exposure, which causes the cardiovascular adaptive syndrome. Different countermeasures have been proposed to decrease its symptomatology, like the application of lower body negative pressure (LBNP). A LBNP box with an environment control system was developed, aiming to improve features of LBNP boxes used worldwide. It consists of five carbon steel ribs in the shape of a cylinder, which is wrapped with high pressure resistant and transparent vinyl. Inner and outer-wheeled trolleys can comfortably and easily move the subject in and out of the box. A custom-made skirt is secured around the subject's waist by an adjustable belt. The other end is secured between two window-type wooden structures, which seal the LBNP box. Inlet and an outlet valves connect the external to the internal environment of the chamber and tube system allows air to circulate gently. Electronic sensors are used to adjust the airflow keeping a pre-set negative pressure without changing humidity and temperature inside the box. Structural, pressure profile and leaking tests were performed with successful results. The improvements of the present LBNP box have substantially decreased the undesirable side effects of uncontrolled environment conditions during rapid pressure changes, and increased test subjects' comfort.
ABSTRACT
A lack of cardiologists in remote areas can delay the diagnosis and the adequate management of cardiovascular emergencies. The digital tele-ECG system (DES) allows electronic data transmission to, and interpretation by, a remote cardiologist. An urban and a rural hospital in Sao Lourenco do Sul city and an outpatient unit in Turucu city employed the DES in Jan 2000, Jan 2001 and June 2003, respectively. DES includes a digital ECG machine, standard computers, a modem connection, telecommunication software and fixed or mobile phones. It allows data to be recorded, transmitted for immediate analysis and stored. A cardiologist performs the ECG analysis remotely, via either fixed or mobile phone, using the same telecommunication software. A total of 1950 digital tele-ECGs have been made in the three locations. The time between data transmission and analysis with online DES is around 9 min in online transmissions. The low cost of this system makes it useful and appropriate for small cities of developing countries where cardiologists are not available for on-site consultation. DES has promoted a significant improvement in the acute management of patients with a consequent decrease in the morbidity and mortality rates from cardiovascular diseases.
ABSTRACT
Educational and outreach programs in space sciences have been a major concern since the beginning of the Space Era. Education curricula in Brazil rarely consider topics related to manned and unmanned space flight. This lack in the Brazilian education system has motivated the development of educational tools, used to demonstrate the effects of hyper- and microgravity on test bodies, both gravitational environments commonly found in aerospace missions. This paper presents the conception and development of a lift and a centrifuge for microgravity and hypergravity research use, respectively. Experiments were recorded via a digital camera and the images acquired were processed for better visualization of the effects of simulated variation in the gravitational force on test bodies. A CD-ROM was then produced for academic purposes. The final goal of this study is to motivate the insertion of space science related topics in the Brazilian elementary and high schools curricula.
Subject(s)
Middle Aged , Humans , Male , Female , Amiodarone , Cineangiography , Coronary Disease , HemodynamicsABSTRACT
Foram analisados sob o ponto de vista hemodinamico e cineangiocardiografico, 8 pacientes da raca branca, 7 do sexo feminino e l do sexo masculino, com idade media de 45 anos e quadro clinico, radiologico e eletrocardiografico compativel com fibrose endomiocardica. Hemodinamicamente, foram encontrados: 1)aumento das pressoes medias de atrio direito (ll,5 + 5,8 mm Hg), diastolica final de ventriculo direito (12,6 +/- 3,0 mm Hg), media de arteria pulmonar (22 +/- 12,7 mm Hg), diastolica final de ventriculo esquerdo (20 +/- 8,8 mm Hg); 2) diminuicao do indice cardiaco (1,9 +/- 0,6 l/min/m2). Do ponto de vista cineangiocardiografico, foram verificados: 1) manutencao em niveis normais do volume diastolico do ventriculo esquerdo (58% +/- 6,5); 3) diminuicao da velocidade media de encurtamento circunferencial (l,09 +/- 0,36 unidades circunferenciais) e 4) alteracoes anatomicas que comprometiam ambos os ventriculos. Insuficiencia mitral isolada foi encontrada em 2 casos e associada a insuficiencia tricuspide em 5 pacientes
Subject(s)
Humans , Male , Female , Cineangiography , Endomyocardial Fibrosis , Arterial PressureABSTRACT
Com o objetivo de avaliar a relacao existente entre a dislipidemia e extensao da aterosclerose coronaria, identificada atraves da cinecoronariografia seletiva, os autores analisaram 161 pacientes, dividindo-se em 4 grupos: grupo 1, constituido por 88 pacientes com colesterol e triglicerideos normais; grupo 2, por 28 pacientes com colesterol aumentado e triglicerideos normais; grupo 3, por 21 pacientes com triglicerideos aumentados e colesterol normal e grupo 4, por 24 pacientes com triglicerideos e colesterol aumentados. A media de idade e a presenca de tabagismo foi semelhante nos 4 grupos estudados, havendo maior frequencia de hipertensao no grupo 4 em relacao ao grupo 1. A analise dos dados revelou que os pacientes dos grupos 1 e 2 apresentaram aterosclerose menos severa e difusa do que os dos grupos 3 e 4; no grupo 3 a extensao da doenca coronariana foi semelhante a do grupo 4. Esses achados sugerem a existencia de uma possivel relacao entre o aumento dos triglicerideos e a extensao da aterosclerose coronaria
Subject(s)
Humans , Male , Female , Coronary Disease , Hyperlipidemias , Triglycerides , CholesterolABSTRACT
Foram estudados 16 pacientes hipertensos, 7 do sexo masculino, com idade media de 56 anos (28 a 76 anos). Apos uso de 0,15 mg/ kg de verapamil por via venosa, houve aumento significativo da pressao media no atrio direito, de 2,3 + ou - 0,6 mm Hg para 3,4 + ou - 0,6 mm Hg (P < 0,05), queda significativa das pressoes aortica maxima, de 165 + ou - 5,4 mm Hg para 136 +ou- 5,4 mm Hg, aortica minima de 87 +/- 3 mm Hg para Hg e aortica media de 119 +/- 4,6 mm Hg para 96 +/- 4,6 mm Hg (P < 0,001), diminuicao da resistencia vascular sistemica de 20 +/- 1 para 15 +/- 1 unidades (P < 0, 001) e da dp/dt maxima do ventriculo esquerdo, de 2350 +/- 115 mm Hg/s para 1923 +/- 115 mm Hg/s (P < 0,05). Observou-se ainda uma tendencia ao aumento do indice cardiaco. A frequencia cardiaca, a pressao media da arteria pulmonar, a pressao diastolica final do ventriculo esquerdo, os volumes diastolicos e sistolicos finais e a fracao de ejecao do ventriculo esquerdo nao se alteraram