Análisis del estrés psíquico en colocadores brasileños de voleibol de alto nivel

En el voleibol competitivo de alto nivel, los jugadores frecuentemente se han de enfrentar a situaciones estresantes. Los colocadores, específicamente son los responsables de armar las jugadas y decidir qué jugador atacará, su ejecución depende en muchas situaciones de la actuación de otros jugadores. ésta y otras situaciones pueden predisponer a este jugador a manifestar una reacción negativa de estrés y perjudicar su rendimiento. Este estudio tiene como objetivo principal analizar las situaciones típicas que los colocadores experimentan durante la competición y verificar, los comportamientos más probables adoptados por estos jugadores en las respectivas situaciones. El instrumento utilizado fue el Test de Estrés Psíquico de Voleibol (TEP-V) compuesto de situaciones estresantes típicas para la posición del jugador. Colaboraron en este estudio 33 colocadores de voleibol de alto nivel, participantes de la Superliga 97/98, siendo 19 jugadores de sexo masculino y 14 de sexo femenino, haciendo un total de 79,2% de dicha población. Los jugadores presentaron una edad media de 24,7 anos (+-4,21) y una experiencia en competición de 10,4 anos (+-4,97). Se comprobó que para los colocadores la situación más estresante se caracteriza por la frase el árbitro senala, una y otra vez, una infracción en mis acciones. Se concluyó que la situación de estar en desventaja después del minuto 25 es más estresante para los colocadores, que estar en desventaja antes (p0.001). Colocadores de sexo masculino atribuyen una carga negativa mayor a la mayoría de situaciones típicas. Independientemente de la situación de estrés afrontada, el comportamiento más probable a ser adoptado por los jugadores de sexo masculino y femenino de las diferentes posiciones (colocadores y atacantes) fue, me tengo que tranquilizar.High level volleyball athletes are confronted with stress situations very often. The principal task of the setters is to prepare the stroke, deciding which player will attack, and his performance is influenced, in many situations, by the actions of the other players. Under such conditions, the athlete is subject to a stressful negative reaction, which is prejudicial to his performance. The purpose of this study is to analyse the most probable behaviors applied by the setters in critical competition situations. The Volleyball Psychological Stress Test (VPS-T) containing typical stressful situations for such players was used as the instrument. This test was applied to 33 setters at the Brazilian Superleague, being 19 males and 14 females, which means 79,2% of the total population. They were 24,7 (± 4,21) years old and 10,4 (± 4,97) years of competitive experience. It was verified that for such players, the most stressing situation was «the referee is, over and over, pointing an infraction in my actions». It was concluded that is most stressful for the players a negative score after the 25' minute than before (p<0.01), and males usually attribute more negative charge to the typical situations. Aside of the stress situation, both males and females players, spikers as well as setters, the behaviors of «trying to control myself' is the most probable to be used

Wholly Aromatic Ether-Imides as n-Type Semiconductors

Some wholly aromatic ether-imides consisting of rod-shaped, relatively-low-mass molecules that can form liquid crystals have been investigated for potential utility as electron-donor-type (ntype) organic semiconductors. It is envisioned that after further research to improve understanding of their physical and chemical properties, compounds of this type would be used to make thin film semiconductor devices (e.g., photovoltaic cells and field-effect transistors) on flexible electronic-circuit substrates. This investigation was inspired by several prior developments: Poly(ether-imides) [PEIs] are a class of engineering plastics that have been used extensively in the form of films in a variety of electronic applications, including insulating layers, circuit boards, and low-permittivity coatings. Wholly aromatic PEIs containing naphthalene and perylene moieties have been shown to be useful as electrochromic polymers. More recently, low-molecular-weight imides comprising naphthalene-based molecules with terminal fluorinated tails were shown to be useful as n-type organic semiconductors in such devices as field-effect transistors and Schottky diodes. Poly(etherimide)s as structural resins have been extensively investigated at NASA Langley Research Center for over 30 years. More recently, the need for multi-functional materials has become increasingly important. This n-type semiconductor illustrates the scope of current work towards new families of PEIs that not only can be used as structural resins for carbon-fiber reinforced composites, but also can function as sensors. Such a multi-functional material would permit so-called in-situ health monitoring of composite structures during service. The work presented here demonstrates that parts of the PEI backbone can be used as an n-type semiconductor with such materials being sensitive to damage, temperature, stress, and pressure. In the near future, multi-functional or "smart" composite structures are envisioned to be able to communicate such important parameters to the flight crew and provide vital information with respect to the operational status of their aircraft

Síndrome de burnout em treinadores brasileiros de voleibol de alto rendimento

O estudo investigou os fatores que podem causar a síndrome de burnout e suas manifestações e efeitos em treinadores de voleibol de alto rendimento. Foram realizadas quinze entrevistas com os treinadores da Superliga Brasileira de Voleibol Masculino 2010/2011. Os dados foram submetidos à análise de conteúdo, sendo, identificadas três categorias: "Fatores que podem causar a síndrome de burnout", "As manifestações do burnout" e "Os efeitos do burnout". Os resultados indicaram que os treinadores possuem fatores que geram estresse em sua profissão. Foram observadas evidências das três dimensões da síndrome de burnout: exaustão física e emocional, reduzido senso de realização esportiva e desvalorização esportiva. Concluímos que estes treinadores apresentaram vulnerabilidade para a manifestação dos sintomas relacionados à síndrome de burnout.El estudio investigó los factores que pueden causar el burnout, así como sus manifestaciones y sus efectos en entrenadores de voleibol de alto rendimiento. Se realizaron quince entrevistas con los entrenadores de la Superliga Brasileña de Voleibol Masculino 2010/2011. Los datos fueron evaluados por medio del análisis de contenido. Se identificaron tres categorías: "Los factores que podrían causar que el síndrome de burnout"; "Las manifestaciones de burnout" y "Los efectos de burnout". Se observaron las tres dimensiones del burnout: agotamiento físico y emocional, reducida sensación de logro deportivo y devaluación deportiva. Los resultados indican que los entrenadores tienen factores que generan estrés en su profesión. Se concluyó que estos entrenadores mostraron vulnerabilidad a la aparición de los síntomas relacionados con el burnout.This study investigated the factors that can cause burnout syndrome, as well as its occurrence and effects in high-performance volleyball coaches. Fifteen interviews were conducted with coaches of the Brazilian Volleyball Male Super League 2010/2011. The data were subjected to content analysis. Three categories were identified: "Factors that could cause burnout syndrome"; "The manifestations of burnout", and "The effects of burnout." Results indicate that coaches have factors that generate stress in their profession. Evidence was observed of the three dimensions of burnout syndrome: physical and emotional exhaustion, a reduced sense of sport accomplishment, and sport devaluation. We concluded that these coaches showed vulnerability to the onset of symptoms related to burnout

Monitoring levels of stress and overtraining in an elite brazilian female volleyball athlete : case study

Overtraining is the result of an imbalance between stress and recovery, in addition to short recovery time and psychosocial events. In this case study, a questionnaire of stress and recovery in sports was used to assess the level of overtraining of an elite female Brazilian volleyball player. The results showed that the heavy loads caused changes in the athlete's profile, resulting in an increase in the fatigue scales. The recovery periods were fundamental to restore her physical and psychological capacities. Finally, the method used detected changes in the athlete's profile after acute events, such as an unexpected defeat. We concluded that changes in the profile of the curve, showed by the instrument, reflected the different moments of the collection, thus reflecting the change in the stress overload. Therefore, the detection or monitoring of stressing factors might be valuable to improve the physical and psychological performance of a team

Benzene at 1GHz. Magnetic field-induced fine structure

The deuterium NMR spectrum of benzene-d6 in a high field spectrometer (1 GHz protons) exhibits a magnetic field-induced deuterium quadrupolar splitting ??. The magnitude of ?? observed for the central resonance is smaller than that observed for the 13C satellite doublets ???. This difference, ?(??) = ??? ? ??, is due to unresolved fine structure contributions to the respective resonances. We determine the origins of and simulate this difference, and report pulse sequences that exploit the connectivity of the peaks in the 13C and 2H spectra to determine the relative signs of the indirect coupling, JCD, and ??. The positive sign found for ?? is consonant with the magnetic field biasing of an isolated benzene molecule—the magnetic energy of the aromatic ring is lowest for configurations where the C6 axis is normal to the field. In the neat liquid the magnitude of ?? is decreased by the pair correlations in this prototypical molecular liquid

El liderazgo de los entrenadores de fútbol sala

En el fútbol sala de alto rendimiento, el conocimiento de las fases que implican el liderazgo en el deporte puede ser un componente que haga la diferencia entre los entrenadores. Este estudio tuvo como objetivo analizar los estilos de liderazgo de varios entrenadores de fútbol sala a nivel competitivo. Las herramientas utilizadas fueron la Escala de Liderazgo Revisado para el Deporte (ELRE) y también un cuestionario de datos demográficos. Participaron en el estudio 26 entrenadores del Campeonato Metropolitano de Fútbol Sala. No se hallaron diferencias estadísticamente significativas en el perfil de liderazgo de entrenadores entre las diferentes categorías ni tampoco cuando se comparó el perfil de liderazgo de los entrenadores en relación al rendimiento de los equipos en la competencia. Se concluyó que los entrenadores se evalúan a sí mismo como líderes democráticos orientados hacia un estilo de interacción fundamentado en el refuerzo positivo.In high level futsal, knowledge of the processes that involve leadership in sports might be a distinguishing characteristic among coaches. This study aimed at analysing the leadership styles of competition futsal coaches. The questionnaire used was the Revised Leadership Scale for Sport (RLSS), in addition to a questionnaire on socio-demographic data. 26 coaches in the Metropolitan Futsal Championship participated in the study. No statistically significant differences were detected as regards the leadership profiles of the coaches in the different categories, or in relation to the performance of the teams in the competition. We concluded that coaches see themselves as democratic leaders whose interaction style is based on positive reinforcement.No futsal de alto rendimento, o conhecimento das fases que implicam a liderança no desporto pode ser um factor que faz a diferença entre os treinadores. Este estudo teve como objectivo analisar os estilos de liderança de vários treinadores de futsal a nível competitivo. As ferramentas utilizadas foram a Escala de Liderança Revista para o Desporto (ELRE) e também o questionário de dados demográficos. Participaram neste estudo 26 treinadores do Campeonato Metropolitano de Futsal. Não se verificaram diferenças estatisticamente significativas no perfil de liderança dos treinadores entre os diferentes escalões, nem quando foram comparados os perfis de liderança dos treinadores em relação ao rendimento das equipas em competição. Concluiu-se que os treinadores se avaliam a si mesmos como lideres democráticos orientados para um estilo de interacção fundamentado no reforço positivo

An Investigation of the Effect of Chewing on Rhythmic Motor Tasks

Chewing gum and walking has traditionally been cited as the quintessentially difficult dual task, but little is known regarding chewing effects on motor control. The aims of this dissertation include describing chewing patterns across adulthood, describing chewing’s influence on secondary motor tasks, and investigate entrainment patterns of chewing and gait per established patterns of coupled oscillators. Three experiments were conducted to describe chewing patterns and to examine the effect chewing has on other motor tasks, particularly walking, in young and old adults. The first experiment used a metronome to manipulate chewing rates and measured associated gait parameters. This experiment established that chewing affects gait. As chewing speed increases or decreases, step rate also changes accordingly. Tasks such as walking, finger tapping, and simple reaction time all slow with advancing age. This experiment established chewing as a task resistant to neuromotor slowing with age. The second experiment examined the effect of chewing on a variety of secondary motor tasks. This experiment confirmed that chewing interferes with performance of a discrete secondary task, such as reaction time, whereas chewing entrains with cyclic movements, like finger tapping and gait. The final experiment varied the timing of when chewing was initiated to highlight the inherent organization of task influence. This experiment confirmed that chewing consistently impacts gait, but not vice versa. A top-down hierarchy where chewing drives changes in gait was substantiated. The physiological basis for the observed behavior is discussed in terms of coupled neural oscillators, such as the central pattern generators in the hindbrain and spinal cord. The findings from the series of experiments highlights oral sensory information as a potentially novel method of influencing movement patterns throughout adulthood. The functional implications of chewing are paramount to survival, but the connection between the mouth and the legs has not been well documented. Understanding the mechanisms associated with this inimitable relationship whereby the mouth is driving leg motion during gait could lead to innovative rehabilitative techniques for gait training

Tilt order parameters, polarity and inversion phenomena in smectic liquid crystals

The order parameters for the phenomenological description of the smectic-{\it A} to smectic-{\it C} phase transition are formulated on the basis of molecular symmetry and structure. It is shown that, unless the long molecular axis is an axis of two-fold or higher rotational symmetry, the ordering of the molecules in the smectic-{\it C} phase gives rise to more than one tilt order parameter and to one or more polar order parameters. The latter describe the indigenous polarity of the smectic-{\it C} phase, which is not related to molecular chirality but underlies the appearance of spontaneous polarisation in chiral smectics. A phenomenological theory of the phase transition is formulated by means of a Landau expansion in two tilt order parameters (primary and secondary) and an indigenous polarity order parameter. The coupling among these order parameters determines the possibility of sign inversions in the temperature dependence of the spontaneous polarisation and of the helical pitch observed experimentally for some chiral smectic-{\it $C^{\ast}$} materials. The molecular interpretation of the inversion phenomena is examined in the light of the new formulation.Comment: 12 pages, 5 figures, RevTe

Direct interaction of human serum proteins with AAV virions to enhance AAV transduction: immediate impact on clinical applications

Recent hemophilia B clinical trials using adeno-associated virus (AAV) gene delivery have demonstrated much lower FIX production in patients compared to the high levels observed in animal models and AAV capsid specific CTLs response elicited at high doses of AAV vectors. These results emphasize the necessity to explore effective approaches for enhancement of AAV transduction. Initially, we found that incubation of all AAV vectors with human serum enhanced AAV transduction. Complementary analytical experiments demonstrated that human serum albumin (HSA) directly interacted with the AAV capsid and augmented AAV transduction. The enhanced transduction was observed with clinical grade HSA. Mechanistic studies suggest that HSA increases AAV binding to target cells and that the interaction of HSA with AAV doesn’t interfere with the AAV infection pathway. Importantly, HSA incubation during vector dialysis also increased transduction. Finally, HSA enhancement of AAV transduction in a model of hemophilia B displayed greater than a 5-fold increase in vector derived circulating FIX, which improved the bleeding phenotype correction. In conclusion, incubation of HSA with AAV vectors supports a universal augmentation of AAV transduction and more importantly, this approach can be immediately transitioned to the clinic for the treatment of hemophilia and other diseases