Quadriceps activation in closed and in open kinetic chain exercise

Purpose: For treatment of various knee disorders, muscles are trained in open or closed kinetic chain tasks. Coordination between the heads of the quadriceps muscle is important for stability and optimal joint loading for both the tibiofemoral and the patellofemoral joint. The aim of this study was to examine whether the quadriceps femoris muscles are activated differently in open versus closed kinetic chain tasks. Methods: Ten healthy men and women (mean age 28.5 +/- 0.7) extended the knees isometrically in open and closed kinetic chain tasks in a reaction time paradigm using moderate force. Surface electromyography (EMG) recordings were made from four different parts of the quadriceps muscle. The onset and amplitude of EMG and force data were measured. Results: In closed chain knee extension, the onset of EMG activity of the four different muscle portions of the quadriceps was more simultaneous than in the open chain. In open chain, rectus femoris (RF) had the earliest EMG onset while vastus medialis obliquus was activated last (7 +/- 13 ms after RF EMG onset) and with smaller amplitude (40 +/- 30% of maximal voluntary contraction (MVC)) than in closed chain (46 +/- 43% MVC). Conclusions: Exercise in closed kinetic chain promotes more balanced initial quadriceps activation than does exercise in open kinetic chain. This may be of importance in designing training programs aimed toward control of the patellofemoral joint.

Winding patterns for actively shielded shim coils with asymmetric target-fields

A method is presented for calculating the currents and winding patterns required to design independent zonal and tesseral shim coils for magnetic resonance imaging. Both actively shielded and unshielded configurations are considered, and the region of interest can be located asymmetrically with respect to the coil's length. Streamline, target-field and Fourier-series methods are utilized. The desired target-field is specified at two cylindrical radii, on and inside a circular conducting cylinder of length 2L and radius a. The specification is over some asymmetric portion pL < z < qL of the coil's length (-1 < p < q < 1). Arbitrary functions are used in the outer sections, -L < z < pL and qL < z < L, to ensure continuity of the magnetic field across the entire length of the coil. The entire field is then periodically extended as a half-range cosine Fourier series about either end of the coil. The resultant Fourier coefficients are then substituted into the Fourier-series expressions for the internal and external magnetic fields, and current densities and stream functions on both the primary coil and shield. A contour plot of the stream function directly gives the required coil winding patterns. Spherical harmonic analysis and shielding analysis on field calculations from a ZX shim coil indicate that example designs and theory are well matched.

Actively shielded multi-layer gradient coil designs with improved cooling properties

In standard cylindrical gradient coils consisting of a single layer of wires, a limiting factor in achieving very large magnetic field gradients is the rapid increase in coil resistance with efficiency. This is a particular problem in small-bore scanners, such as those used for MR microscopy. By adopting a multi-layer design in which the coil wires are allowed to spread out into multiple layers wound at increasing radii, a more favourable scaling of resistance with efficiency is achieved, thus allowing the design of more powerful gradient coils with acceptable resistance values. Previously this approach has been applied to the design of unshielded, longitudinal, and transverse gradient coils. Here, the multi-layer approach has been extended to allow the design of actively shielded multi-layer gradient coils, and also to produce coils exhibiting enhanced cooling characteristics. An iterative approach to modelling the steady-state temperature distribution within the coil has also been developed. Results indicate that a good level of screening can be achieved in multi-layer coils, that small versions of such coils can yield higher efficiencies at fixed resistance than conventional two-layer (primary and screen) coils, and that performance improves as the number of layers of increases. Simulations show that by optimising multi-layer coils for cooling it is possible to achieve significantly higher gradient strengths at a fixed maximum operating temperature. A four-layer coil of 8 mm inner diameter has been constructed and used to test the steady-state temperature model. (C) 2003 Elsevier Inc. All rights reserved.

Applied physiology and game analysis of rugby union

Increased professionalism in rugby has elicited rapid changes in the fitness profile of elite players. Recent research, focusing on the physiological and anthropometrical characteristics of rugby players, and the demands of competition are reviewed. The paucity of research on contemporary elite rugby players is highlighted, along with the need for standardised testing protocols. Recent data reinforce the pronounced differences in the anthropometric and physical characteristics of the forwards and backs. Forwards are typically heavier, taller, and have a greater proportion of body fat than backs. These characteristics are changing, with forwards developing greater total mass and higher muscularity. The forwards demonstrate superior absolute aerobic and anaerobic power, and Muscular strength. Results favour the backs when body mass is taken into account. The scaling of results to body mass can be problematic and future investigations should present results using power function ratios. Recommended tests for elite players include body mass and skinfolds, vertical jump, speed, and the multi-stage shuttle run. Repeat sprint testing is a possible avenue for more specific evaluation of players. During competition, high-intensity efforts are often followed by periods of incomplete recovery. The total work over the duration of a game is lower in the backs compared with the forwards; forwards spend greater time in physical contact with the opposition while the backs spend more time in free running, allowing them to cover greater distances. The intense efforts undertaken by rugby players place considerable stress on anaerobic energy sources, while the aerobic system provides energy during repeated efforts and for recovery. Training should focus on repeated brief high-intensity efforts with short rest intervals to condition players to the demands of the game. Training for the forwards should emphasise the higher work rates of the game, while extended rest periods can be provided to the backs. Players should not only be prepared for the demands of competition, but also the stress of travel and extreme environmental conditions. The greater professionalism of rugby union has increased scientific research in the sport; however, there is scope for significant refinement of investigations on the physiological demands of the game, and sports-specific testing procedures.

Use of web-based formative assessment to support student learning in metabolism/nutrition unit

In 2002, an integrated basic science course was introduced into the Bachelor of Dental Sciences programme at the University of Queensland, Australia. Learning activities for the Metabolism and Nutrition unit within this integrated course included lectures, problem-based learning tutorials, computer-based self-directed learning exercises and practicals. To support student learning and assist students to develop the skills necessary to become lifelong learners, an extensive bank of formative assessment questions was set up using the commercially available package, WebCT®. Questions included short-answer, multiple-choice and extended matching questions. As significant staff time was involved in setting up the question database, the extent to which students used the formative assessment and their perceptions of its usefulness to their learning were evaluated to determine whether formative assessment should be extended to other units within the course. More than 90% of the class completed formative assessment tasks associated with learning activities scheduled in the first two weeks of the block, but this declined to less than 50% by the fourth and final week of the block. Patterns of usage of the formative assessment were also compared in students who scored in the top 10% for all assessment for the semester with those who scored in the lowest 10%. High-performing students accessed the Web-based formative assessment about twice as often as those who scored in the lowest band. However, marks for the formative assessment tests did not differ significantly between the two groups. In a questionnaire that was administered at the completion of the block, students rated the formative assessment highly, with 80% regarding it as being helpful for their learning. In conclusion, although substantial staff time was required to set up the question database, this appeared to be justified by the positive responses of the students.

Instrumentation used to measure residential magnetic fields and currents

The equipment used to measure magnetic fields and, electric currents in residences is described. The instrumentation consisted of current transformers, magnetic field probes and locally designed and, built signal conditioning modules. The data acquisition system was capable of unattended recording for extended time periods. The complete system was calibrated to verify its response to known physical inputs. (C) 2003 ISA-The Instrumentation Automation Society.

Subsoil nitrogen mineralisation and its potential to contribute to NH4 accumulation in a Vertosol

High concentrations of NH4+ (up to 270 kg N/ha) have been observed in a Vertosol below 1 m depth in south-east Queensland. This study examined the possibility that mineralisation associated with the removal of native vegetation (Acacia harpophylla) for cropping was responsible for the production of NH4+. Particularly, the potential contribution of decomposing root material and/or dissolved organic nitrogen (DON) leached into the subsoil after clearing was investigated. The amount of N that was contained within native vegetation root material was determined from an area of native vegetation adjacent to the cleared site containing elevated NH4+ concentrations. In addition, the amount of NH4+ that could be mineralised in the native vegetation soil was determined by monitoring NH4+ concentrations over 360 days in intact cores, and by conducting waterlogged incubations. To determine the rate at which a source of DON leached into the subsoil would mineralise, soil was amended with glutamic acid at a rate of 250 mg N/kg and placed under waterlogged incubation. The possibility that the acidic pH of the subsoil, or the lack of a significant subsoil microbial population, was inhibiting mineralisation was also examined by increasing soil pH from 4.4 to 7.0, and inoculating the subsoil with surface soil microorganisms during waterlogged incubations. Low concentrations of N, approximately 90 kg N/ha between 1.2 and 3 m, were found in the native vegetation root material. In addition, no net N mineralisation was observed in either the extended incubation of intact cores or in the control samples of the waterlogged incubations. Net N mineralisation was also not detected when the subsoil was amended with a source of organic N. Results indicate that this lack of mineralisation is largely due to pH inhibition of the microbial population. It is concluded that the mineralisation of either in situ organic material, or DON transported to the subsoil during leaching events, is unlikely to have significantly contributed to the subsoil NH4 accumulation at the study site.

Induction in the timed interval calculus

The Timed Interval Calculus, a timed-trace formalism based on set theory, is introduced. It is extended with an induction law and a unit for concatenation, which facilitates the proof of properties over trace histories. The effectiveness of the extended Timed Interval Calculus is demonstrated via a benchmark case study, the mine pump. Specifically, a safety property relating to the operation of a mine shaft is proved, based on an implementation of the mine pump and assumptions about the environment of the mine. (C) 2002 Elsevier Science B.V. All rights reserved.

Measuring the accumulated hazards of smoking: global and regional estimates for 2000

Objective: Current prevalence of smoking, even where data are available, is a poor proxy for cumulative hazards of smoking, which depend on several factors including the age at which smoking began, duration of smoking, number of cigarettes smoked per day, degree of inhalation, and cigarette characteristics such as tar and nicotine content or filter type. Methods: We extended the Peto-Lopez smoking impact ratio method to estimate accumulated hazards of smoking for different regions of the world. Lung cancer mortality data were obtained from the Global Burden of Disease mortality database. The American Cancer Society Cancer Prevention Study, phase 11 (CPS-II) with follow up for the years 1982 to 1988 was the reference population. For the global application of the method, never-smoker lung cancer mortality rates were chosen based on the estimated use of coal for household energy in each region. Results: Men in industrialised countries of Europe, North America, and the Western Pacific had the largest accumulated hazards of smoking. Young and middle age males in many regions of the developing world also had large smoking risks. The accumulated hazards of smoking for women were highest in North America followed by Europe. Conclusions: In the absence of detailed data on smoking prevalence and history, lung cancer mortality provides a robust indicator of the accumulated hazards of smoking. These hazards in developing countries are currently more concentrated among young and middle aged males.

Relat??rio final do projeto desenvolvimento de capacidade de lideran??a (Brasil-Canad??)

Desde o in??cio de 2000, a Canada School of Public Service (CSPS) e a Escola Nacional de Administra????o P??blica (ENAP) demonstraram interesse na possibilidade de coopera????o para desenvolver capacidades de gest??o de servidores p??blicos brasileiros. Um acordo assinado em 2003, inicialmente foi planejado para ser uma parceria de tr??s anos entre as duas escolas. No entanto, a parceria continua at?? hoje e agora estamos no final do segundo, e ??ltimo projeto de coopera????o t??cnica financiado pela Canadian International Development Agency (CIDA) entre Brasil e Canad??, denominado ???Desenvolvimento da Capacidade de Governan??a???. Este relat??rio representa o resultado deste segundo projeto, o qual ampliou o esfor??o de capacita????o da primeira parceria, focando agora em funcion??rios p??blicos mais pr??ximos da "linha de frente" da presta????o de servi??os, aumentando assim a efic??cia do governo nessas ??reas. O projeto mostrou ser bem-sucedido, principalmente, porque seguiu de perto os princ??pios do desenvolvimento eficaz e sustent??vel. Considerando a sua miss??o de desenvolver compet??ncias de servidores p??blicos, a ENAP deu prioridade, dentro deste projeto de coopera????o com o Canad??, a atividades que visam refor??ar a capacidade de governan??a do pa??s, trabalhando em conjunto com escolas em cinco regi??es: Norte, Nordeste, Centro-Oeste, Sudeste e Sul, com especial ??nfase nas ??reas mais pobres do pa??s, localizadas nas regi??es Norte e Nordeste. Foram participantes-chave neste projeto: i) seis escolas brasileiras regionais de administra????o p??blica; ii) uma das principais institui????es acad??micas do Canad?? - Queen's University, e iii) o Minist??rio do Desenvolvimento Social e Combate ?? Fome e tr??s Secretarias de Ra??a, Direitos Humanos e Pol??ticas para as Mulheres. Neste projeto, a CSPS compartilhou suas metodologias em educa????o a dist??ncia, lideran??a e gest??o p??blica. Trabalhando com parceiros brasileiros, ela tamb??m transferiu e adaptou curr??culos e conte??dos de seus cursos. A CIDA forneceu $1.845.000,00 por meio da Programa de Interc??mbio de Conhecimentos para a Promo????o da Eq??idade (PIPE) Brasil-Canad??. A ENAP e as EPBs contribu??ram com $993,752 e a CSPS contribuiu com material de curso, conhecimento e apoio t??cnico no valor de $ 1.000.000

Aprendizagem por imitação através de mapeamento Visuomotor baseado em imagens omnidirecionais

Este trabalho propõe uma metodologia de aprendizagem que permite a um robô aprender uma tarefa adaptando-a e representando-a de acordo com a sua capacidade motora e sensorial. Primeiramente, um mapeamento sensoriomotor é criado e converte informação sensorial em informação motora. Depois, através de imitação, o robô aprende um conjunto de ações elementares formando um vocabulário motor. A imitação é baseada nas representações motoras obtidas com o mapeamento sensoriomotor. O vocabulário motor criado é então utilizado para aprender e realizar tarefas mais sofisticadas, compostas por seqüências ou combinações de ações elementares. Esta metodologia é ilustrada através de uma aplicação de mapeamento e navegação topológica com um robô móvel. O automovimento é utilizado como mapeamento visuomotor, convertendo o fluxo óptico em imagens omnidirecionais em informação motora (translação e rotação), a qual é usada para a criação de um vocabulário motor. A seguir, o vocabulário é utilizado para mapeamento e navegação topológica. Os resultados obtidos são interessantes e a abordagem proposta pode ser estendida a diferentes robôs e aplicações.

Os processos de formação na Política Nacional de Humanização : a experiência de um curso para gestores e trabalhadores da atenção básica em saúde

Este artigo tem como objetivo relatar a experiência de um curso de formação da Política Nacional de Humanização voltado para gestores e trabalhadores da atenção básica de um município no estado do Rio de Janeiro. O curso visou a formação de apoiadores institucionais capazes de fomentar rede no Sistema Único de Saúde (SUS), promover mudanças e consolidação nos modos de atenção e de gestão dos serviços. Como referencial metodológico, buscou-se um modo de "formação-intervenção" que fosse baseado em práticas concretas de intervenção dos trabalhadores nos processos de trabalho em saúde. O curso envolveu quarenta participantes, gestores e trabalhadores de nível médio e superior, ligados à atenção básica, oriundos da Estratégia de Saúde da Família e de Unidades de Saúde. Como resultados destacam-se ações de co-gestão no formato de reuniões com os usuários para o compartilhamento de decisões relativas ao serviço; implementação de acolhimento, com intervenções que garantam o acesso do usuário ao serviço; e de clínica ampliada, com discussões em equipe dos casos clínicos; e ações no campo da saúde do trabalhador, como efeito das discussões dos processos de trabalho nas equipes multiprofissionais.

Educação escolar Tupinikim e Guarani : experiências de interculturalidade em aldeias de Aracruz, no Estado do Espírito Santo

A pesquisa analisa as relações entre interculturalidade, práxis e educação escolar indígena Tupinikim e Guarani do município de Aracruz, Espírito Santo, Brasil. Investiga a práxis da educação intercultural no espaço da educação escolar indígena como meio de revitalização das culturas Tupinikim e Guarani. Objetiva problematizar a formação inicial e continuada dos professores indígenas; discutir a práxis da interculturalidade no contexto da educação escolar indígena; e, identificar outros espaços educativos da cultura e educação indígena. Analisa aspectos teóricos e práticos sobre cultura (WILLIAMS, 2008; BRANDÃO, 1989; FORQUIN, 1993; CANDAU, 2011; GEERTZ, 1989), interculturalidade (D‘AMBROSIO,1996; FLEURI, 2002; 2003; SCANDIUZZI, 2009;), identidade e alteridade (MELIÁ, 2000; FREIRE, 1981; 1987; LITAIFF, 2004) e práxis (FREIRE, 1989; VÁSQUEZ, 2011; SEMERARO, 2006) e educação (escolar) indígena de acordo com a legislação vigente. Realiza pesquisa interpretativa (GEERTZ, 1989) na educação escolar indígena junto aos professores indígenas Guarani das Aldeias de Boa Esperança e Três Palmeiras (2009-2010) e professores indígenas Tupinikim da Aldeia de Comboios (2011-2013) na perspectiva de um diálogo intercultural. Contribuem nos processos investigativos para produção, sistematização e análise de dados a realização de observações, entrevistas semiestruturadas, registros no caderno de campo, fotografias, gravações em áudio e em vídeo e análise documental sobre a educação escolar indígena de Aracruz. (ANDRÉ, 2007; GIL, 1999; 2004). Os resultados deste trabalho levantam questões relativas a duas realidades de educação escolar nas comunidades indígenas pesquisadas que se constituem em aspectos de sobrevivência e desencadeia formas para interagir e reagir em defesa de sua identidade e dignidade. Nesse sentido, a escola é um local de vivências e de encontro, vista e sentida pelas lideranças e pela comunidade como uma possibilidade real para desenvolver um elo entre as formas tradicionais de vida e as formas contemporâneas. O desafio de garantir uma escola nestes termos significa concretizar a proposta de um projeto de educação escolar para os povos indígenas, constituído por especificidades de como trabalhar a terra, pelo reconhecimento de suas tradições, das línguas e da memória coletiva. Distante de apresentar respostas conclusivas propõe uma educação escolar, coletiva e participativa, que critica e dialoga com todos os envolvidos no processo educativo.