AN INVERSE METHOD FOR PREDICTING THE MECHANICS OF HOPPING FROM MOTION DATA INPUT

By segmentation of the body, this study estimated both the natural frequency and mode shapes of the mechanics of hopping, during a stance phase, using a purposely developed three degree-of-freedom state space model of the leg. The model, which was validated via comparison of measured and estimated motion data, incorporated a novel use of the Bellman-Quasilinearization technique estimators. Vertical displacements of the centre of mass of each segment (thigh, shank, and foot) were collected during a stance phase and used as observed data for unknown leg compliance parameters. It was found that the relative joint contributions to compliance during an exhaustive hopping appear to be tuned in part, to the type of foot-surface landing (input signals)

O ensino étnico nos Estados Unidos: as escolas oficiais portuguesas e a comunidade lusófona

[Resumo] Um dos objectivos fundamentais das Escolas Étnicas Comunitárias, nos Estados Unidos, é o de preservar e transmitir a língua, cultura e etnicidade as gerações vindouras. Um grupo de estudantes Luso-Americanos (G1) com significativa frequencia das Escolas Oficiais Portuguesas foi comparado com um outro grupo de estudantes Luso-Americanos (G2) que nao frequentou as referidas escolas. Foram utilizados dois instrumentos de investigação na recolha de dados estatísticos: 1. BentoRibeiro Cultural Identification Scale (B-RCIS), urna escala dicotómica de 36 itens para medir a identidade cultural em tres categorias; 2. Socio-Educational Portuguese Profile (SEEP), um instrumento de 22 itens construído para este estudo para a obtenção de dados demográficos e atitudes em relação a língua Portuguesa. A população deste estudo (n=236) consistiu em duas amostras: um grupo constituído por todos os alunos Luso-Americanos disponíveis com idades entre os 12 e os 17 anos (n=120) frequentando as Escolas Oficiais Portuguesas na costa leste dos Estados Unidos; Este grupo foi comparado com urna segunda amostra de estudantes Luso-Americanos (n = 116) sem frequencia das Escolas Oficiais Portuguesas. Resultados revelaram que a frequencia nas Escolas Oficiais Portuguesas contribuiu significativamente para a preservação dos valores culturais e linguísticos e para o desenvolvimento e reafirmação da COMUNIDADE LUSÓFONA

Leadership of portuguese community schools in the East Coast of the United States and the public policies of education: a multiple case studies

The Portuguese community schools of the United States located in the areas of larger Portuguese population concentration are social organizations that come materializing throughout decades the designs of the educative policies of the Portuguese government in relation to the expansion and preservation of the language, the culture and the history of Portugal. These designs of the educative policies are enrolled in the Constitution of the Republic (1976), in the Basic Law of Educative System (1986) and, over all, in the successive legislative norms (Decree-laws and ordinances) of the successive governments. Portuguese community schools in the United States are structuralized in analogous way to schools of the Portuguese geographic space. For this qualitative study (multiple case), four directors of Portuguese schools of the East Coast of the United States were interviewed; two schools are in the state of Rhode Island and the other two are in the state of Massachusetts. Also, it was administered the questionnaire on practices of leadership “Leadership Practices Inventory” (LPI) of Kouzes and Posner (2002) to collect additional data about practices of leadership on the directors of the schools. The LPI evaluates practices of leadership classifying them in five domains: (a) Model the way; (b) Inspire a shared vision; (c) Challenge the process; (d) Enable others to act; and, (e) Encourage the heart. Results of this qualitative research indicate that the Portuguese Government has not had an educative policy stimulant, coherent and consistent of support, incentive, maintenance and diffusion of the Portuguese language and culture and the directors of the studied schools they have a proactive and serving leadership style in conducting the management of Portuguese community schools. The five practices of leadership are highly practiced by the directors of the studied schools above all the practices “Enable others to act” and “Encourage the heart”

RELATIVE CONTRIBUTION OF THE JOINT MOMENTS TO THE ANGULAR ACCELERATION OF THE LOWER LIMB IN HOPING EXERCISE

The purpose of this study was to estimate the ability of joint moments to transfer mechanical energy through all the leg segments during a cyclic hoping exercise. The technique was applied to data from 4 triathlon athletes to characterize the relative ability of the lower limb joint moments to accelerate the ankle, knee and hip joints. Our findings show that the strategies used to maintain the same jumping height rely on the balance between the joint net moments to guarantee the acceleration of the joints. While the ankle and knee moments reduced their contribution to accelerate the ankle and the knee joints, the hip moments increased their participation

INFLUENCE OF BODY POSITION ON DOLPHIN KICK KINEMATICS

In backstroke, butterfly and front crawl competitive swimming underwater glide after the starts and turns is followed by a series of dolphin kicks while the body is still completely submerged. The aim of this study was to analyze the kinematics of dolphin kick in three body positions, prone, dorsal and lateral. Six national level junior swimmers (17.02 ± 0.36 years) were filmed underwater after jumping from the start blocks in order to analyze 2 complete kick cycles at maximal velocity in each position (APAS). Lateral kicking showed lower frequency and higher feet, hip, elbow and hand transverse amplitude. Swimmers used higher ankle extension in the dorsal kick. Strouhal number (dorsal: 0.95±1.31; prone: 0.86±0.07; lateral: 0.95±0.83) were within the range of previous results for subelite swimmers but failed to discriminate body positions

Mixed reality in an operating room using Hololens 2: the use of the remote assistance from manufacturers techinicians during the surgeries

Proceeding paper[Abstract] The aim of this work is that the participants, using HoloLens 2 and Dynamics 365 Remote Assistance, can receive all the training and information necessary for the correct application of prosthesis and medical devices remotely, from a support center of the manufacturers, avoiding the displacement and presence of these technicians during surgeries. After implementing this method, an analysis will be made on its impact, avoiding displacement and the presence of technicians during surgery, in terms of increasing satisfaction and improving the experience of the participants, reduction of various risks (including the risk of infection) and on reduction of some economic and environmental costs

The influence of brain activity on the interactive process through biofeedback mechanisms in virtual reality environments

Proceeding paper[Abstract] This work focuses on the development of a software link interface tool between the Looxid Link Device coupled to the HTC Vive Pro VR HeadSets and the Unity platform, to generate real-time interactivity in virtual reality applications. The software incorporates a dynamic and parameterizable algorithm to be used as a core-engine in the real-time Biofeedback process, recognizing the values of the biological signals registered in each of the EEG channels of the Looxid Link device. The values of EEG frequencies detected in real time can be used to generate elements of interactivity, with different frequencies and intensities

UPPER LIMB KINETICS BETWEEN TWO DIFFERENT STANCES IN A TENNIS FOREHAND DRIVE: A PRELIMINARY STUDY

The purpose of this study was to compare the joint moments of force of the upper limb between one forehand drive performed in quasi-static stance (QSS) (with both feet on the ground at the impact) and one forehand performed with a dynamic frontal weight transfer stance (DS) (with both feet off the ground at the impact). One high-performance tennis player was recorded with an optical system with a frequency of 240Hz during both techniques. Three forehands in QSS and three in DS were selected for analysis. Results demonstrated that the forehand performed with QSS could present higher moments of force, especially in the shoulder joint abdu/addu (QSS:45.5 vs DS:52.8 Nm), moreover, the DS presented higher racket velocity compared with the QSS forehand drive (DS: 32.7(0.4) vs QSS:31.5(0.4) m/s). The results of this study could present an important information for tennis coaches as for their players in order to understand which forehand technique creates higher joint loads, and, therefore adapt the practice for each situation

3D KINEMATICS OF GAIT PATTERN IN ACTIVE ELDERLY MEN

Gait is one of the most important means for the maintenance of an independent life and gait pattern (GP) seems to be associated with falls and, therefore, with the quality of life in the elderly. On the other side, exercise is associated with the maintenance of the physical function and quality of life. Therefore, the purpose of our study was to determine if moderate/vigorous exercise could retain GP with aging. The sample had two groups of subjects: one of five young males (21.8 (0.45) y) and the other of three old males (69.3 (8.4) y). Kinematics data were determined and compared between groups. No significant differences were found between the groups and therefore exercise practise seems to maintain GP trough aging. However, these results should be seen in a conservative way due to the small number of participants of this study

DYNAMICS OF GAIT IN ACTIVE ELDERLY MEN

The purpose of this study was to identify if, on very active elderly male, the undesirables effects of age in gait dynamic variables where minimized. The gait cycle of 3 healthy and active elderly males (ages: 69.30±1.41 years) and 5 health and active young males (ages: 21.80±0.45 years) was compared in order to verify if the differences (between young and older adults) usually reported in the literature were present. The following kinetics variables were studied: ground reaction force (vertical and anterior-posterior components), joint torques and joint power (ankle, knee and hip joints). The dynamic variables were collected using the inverse dynamics technique. The results show no significant differences between the two groups in ground reaction force, joint torques and joint power. Our results seem to indicate that elderly functional decline is minimized with exercise