Grip and load force coordination in cyclical isometric manipulation task is not affected by the feedback type

Background: The relationship between normal and tangential force components (grip force - GF and load force - LF, respectively) acting on the digits-object interface during object manipulation reveals neural mechanisms involved in movement control. Here, we examined whether the feedback type provided to the participants during exertion of LF would influence GF-LF coordination and task performance. Methods. Sixteen young (24.7 ±3.8 years-old) volunteers isometrically exerted continuously sinusoidal FZ (vertical component of LF) by pulling a fixed instrumented handle up and relaxing under two feedback conditions: targeting and tracking. In targeting condition, FZ exertion range was determined by horizontal lines representing the upper (10 N) and lower (1 N) targets, with frequency (0.77 or 1.53 Hz) dictated by a metronome. In tracking condition, a sinusoidal template set at similar frequencies and range was presented and should be superposed by the participants' exerted FZ. Task performance was assessed by absolute errors at peaks (AEPeak) and valleys (AEValley) and GF-LF coordination by GF-LF ratios, maximum cross-correlation coefficients (r max), and time lags. Results: The results revealed no effect of feedback and no feedback by frequency interaction on any variable. AE Peak and GF-LF ratio were higher and rmax lower at 1.53 Hz than at 0.77 Hz. Conclusion: These findings indicate that the type of feedback does not influence task performance and GF-LF coordination. Therefore, we recommend the use of tracking tasks when assessing GF-LF coordination during isometric LF exertion in externally fixed instrumented handles because they are easier to understand and provide additional indices (e.g., RMSE) of voluntary force control. © 2013 Pedão et al.; licensee BioMed Central Ltd.

Performance of Down syndrome subjects during a coincident timing task

Background: The time synchronization is a very important ability for the acquisition and performance of motor skills that generate the need to adapt the actions of body segments to external events of the environment that are changing their position in space. Down Syndrome (DS) individuals may present some deficits to perform tasks with synchronization demand. We aimed to investigate the performance of individuals with DS in a simple Coincident Timing task. Method. 32 individuals were divided into 2 groups: the Down syndrome group (DSG) comprised of 16 individuals with average age of 20 (+/- 5 years old), and a control group (CG) comprised of 16 individuals of the same age. All individuals performed the Simple Timing (ST) task and their performance was measured in milliseconds. The study was conducted in a single phase with the execution of 20 consecutive trials for each participant. Results: There was a significant difference in the intergroup analysis for the accuracy adjustment - Absolute Error (Z = 3.656, p = 0.001); and for the performance consistence - Variable Error (Z = 2.939, p = 0.003). Conclusion: DS individuals have more difficulty in integrating the motor action to an external stimulus and they also present more inconsistence in performance. Both groups presented the same tendency to delay their motor responses. © 2013 Torriani-Pasin et al.; licensee BioMed Central Ltd.

Transformación y desarrollo: la gran tarea de América Latina (capítulos I y VIII) = Change and development: Latin America's great task (chapters I and VIII)

Incluye Bibliografía

Some considerations on the nature of the task faced by the IRG, and a few suggestions as to how to organize its activities, with particular reference to Latin America

Includes bibliography

Some considerations on the nature of the task faced by the IRG, and a few suggestions as to how to organize its activities, with particular reference to Latin America

Includes bibliography

Report of the special task force on collaboration in agricultural research

Presenta recomendaciones para establecer un criterio de colaboracion entre las agencias que operan en la region en el ambito de la investigacion agricola.

Transformación productiva con equidad: la tarea prioritaria del desarrollo de América Latina y el Caribe en los años noventa = Changing production patterns with social equity: the prime task of Latin American and Caribbean development in the 1990s

Incluye Bibliografía

Transformación y desarrollo: la gran tarea: informe presentado al Banco Interamericano de Desarrollo = Change and development: Latin America's great task: report submitted to the Inter-American Development Bank

Incluye Bibliografía

Where do Latin America and the Caribbean stand in relation to the eLAC2007 Plan of Action?: evidence from available information

Includes bibliography

A disciplina de ginástica artística na formação do licenciado em educação física sob a perspectiva de docentes universitários

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The right to education: An unfinished task for Latin America and the Caribbean

The right to education.Our newsletter once again takes on the challenges set forth by the Millennium Declaration and the human rights approach embedded in the Convention on the Rights of the Child. In this issue, we will examine the right of children and adolescents to education.

Regional report on measuring disability: Overview of the disability measurement procedures in Latin America and the Caribbean. Task Force on Disability Measurement Statistical Conference of the Americas (SCA)

Introduction .-- I. Inclusion of international guidelines in disability measurement processes in Latin American and Caribbean countries .-- II. State of the art in disability measurement in the region’s countries .-- III. Main difficulties facing countries in terms of collecting information .-- Conclusions.

Expectations and industrial output in Uruguay: Sectoral interdependence and common trends

This paper examines the interdependence between expectations and growth by analysing Uruguayan manufacturing industry, divided for the purpose into four industry groupings differentiated by trade participation and production specialization. The study shows that there is a long-run relationship between industrialists' expectations and output growth in each grouping. In the most trade-oriented groupings the relationship is one of predetermination, showing how useful expectations are as a guide to sectoral growth. Expectations in the four industrial groupings are shown to follow a common long-run trend, identified with the one guiding the export grouping. Impulse-response simulations derived from a multisectoral vector autoregression (VAR) model confirm the important role of the industries most exposed to international competition in spreading shorter-term shocks.