The effects of qualitatively different acute physical activity interventions in real-world settings on executive functions in preadolescent children

There is growing evidence indicating a positive effect of acute physical activity on cognitive performance in children. Most of the evidence originates, however, from studies in highly controlled laboratory settings. The aim of the present study was to investigate whether the same effects can be found in more real-world settings. We examined the effects of qualitatively different acute physical activity interventions on the three core dimensions of executive functions (updating, inhibition, shifting). In an experimental between-subject design, 219 ten to twelve year-olds were assigned to one of four conditions which varied systematically in physical activation and cognitive engagement. Executive functions were measured before and immediately after the intervention. Contrary to the hypothesis, no effects of acute physical activity with and without cognitive engagement were found on executive functions in the overall sample. Only children with higher fitness and/or higher academic achievement benefitted from the interventions in terms of their updating performance. Thus, the results indicate that it may be more difficult to attain positive effects through acute physical activity in real-world settings than in laboratory settings and that physiological and cognitive requirements may have to be adjusted to individual capacity to make an intervention effective.

Cognitively engaging chronic physical activity, but not aerobic exercise, affects executive functions in primary school children: A group-randomized controlled trial

Although the positive effects of different kinds of physical activity (PA) on cognitive functioning have already been demonstrated in a variety of studies, the role of cognitive engagement in promoting children’s executive functions is still unclear. The aim of the present study was therefore to investigate the effects of two qualitatively different chronic PA interventions on executive functions in primary school children. 181 children aged between 10 and 12 years were assigned to either a 6-week physical education program with a high level of physical exertion and high cognitive engagement (team games), a physical education program with high physical exertion but low cognitive engagement (aerobic exercise), or to a physical education program with both low physical exertion and low cognitive engagement (control condition). Executive functions (updating, inhibition, shifting) and aerobic fitness (multistage 20-meter shuttle run test) were measured before and after the respective condition. Results revealed that both interventions (team games and aerobic exercise) have a positive impact on children’s aerobic fitness (4-5 % increase in estimated VO2max). Importantly, an improvement in shifting performance was found only in the team games and not in the aerobic exercise or control condition. Thus, the inclusion of cognitive engagement in PA seems to be the most promising type of chronic intervention to enhance executive functions in children, providing further evidence for the importance of the qualitative aspects of PA.

STUDY OF THE EFFECTS OF TOTAL MODULATION TRANSFER FUNCTION CHANGES ON OBSERVER PERFORMANCE USING CLINICAL MAMMOGRAMS

The main goal of this study was to relate physical changes in image quality measured by Modulation Transfer Function (MTF) to diagnostic accuracy.^ One Hundred and Fifty Kodak Min-R screen/film combination conventional craniocaudal mammograms obtained with the Pfizer Microfocus Mammographic system were selected from the files of the Department of Radiology, at M.D. Anderson Hospital and Tumor Institute.^ The mammograms included 88 cases with a variety of benign diagnosis and 62 cases with a variety of malignant biopsy diagnosis. The average age of the patient population was 55 years old. 70 cases presented calcifications with 30 cases having calcifications smaller than 0.5mm. 46 cases presented irregular bordered masses larger than 1 cm. 30 cases presented smooth bordered masses with 20 larger than 1 cm.^ Four separated copies of the original images were made each having a different change in the MTF using a defocusing technique whereby copies of the original were obtained by light exposure through different thicknesses (spacing) of transparent film base.^ The mammograms were randomized, and evaluated by three experienced mammographers for the degree of visibility of various anatomical breast structures and pathological lesions (masses and calicifications), subjective image quality, and mammographic interpretation.^ 3,000 separate evaluations were anayzed by several statistical techniques including Receiver Operating Characteristic curve analysis, McNemar test for differences between proportions and the Landis et al. method of agreement weighted kappa for ordinal categorical data.^ Results from the statistical analysis show: (1) There were no statistical significant differences in the diagnostic accuracy of the observers when diagnosing from mammograms with the same MTF. (2) There were no statistically significant differences in diagnostic accuracy for each observer when diagnosing from mammograms with the different MTF's used in the study. (3) There statistical significant differences in detail visibility between the copies and the originals. Detail visibility was better in the originals. (4) Feature interpretations were not significantly different between the originals and the copies. (5) Perception of image quality did not affect image interpretation.^ Continuation and improvement of this research ca be accomplished by: using a case population more sensitive to MTF changes, i.e., asymptomatic women with minimum breast cancer, more observers (including less experienced radiologists and experienced technologists) must collaborate in the study, and using a minimum of 200 benign and 200 malignant cases.^

Oxygen Supplementing, Biocompatible Outer Membranes for Enhanced Performance of Implantable Glucose Sensors

Lack of linearity and sensitivity, oxygen dependence, biofouling and tissue inflammation hinder the development of implantable biosensors for continuous monitoring of glucose. Herein, we report the development of stacked outer membranes based on LBL/PVA hydrogels that improve sensor sensitivity, linearity, oxygen independence and counter biofouling and inflammation. While the inner LBL membrane affords tunable diffusivity, the outer PVA is capable of releasing anti-inflammatory drugs/tissue response modifying agents to counter acute and chronic inflammation, and to induce neo-angiogenesis at the implant site. Sensors were fabricated by immobilizing GOx enzyme on top of 50 μm platinum wires, followed by deposition of stacked LBL/PVA hydrogel membranes. The response of the sensors at 0.7V to various glucose concentrations was studied. Michelis-Menten analysis was performed to quantify sensor performance in terms of linearity and oxygen dependence. The interplay between sensor performance and inward glucose diffusivity was elucidated using (i) various LBL membranes and (ii) various freeze-thaw (FT) cycles of PVA. Incorporation of LBL/PVA stacked membranes resulted in an 8 fold increase in sensor linearity and a 9 fold decrease in oxygen dependence compared to controls. The enhancement in the sensor performance is attributed to (i) the oxygen storing capability of PVA hydrogel due to the formation of hydrophobic domains during its freezing/ thawing employed for its physical crosslinking and (ii) regulation of glucose flux by the inner LBL membrane. Such membranes offer significant advantages over presently available outer membranes in lieu of (i) their ability to control inflammation, (ii) their modulus that closely matches that of subcutaneous human tissue, (iii) non-necessity of reactive chemical crosslinking agents, (iv) tunable sensitivity and (v) supplemental storage of oxygen.

Physical fitness of industrial firefighters

Firefighting is widely known to be one of the most physically demanding civilian occupations. A subset of this is Industrial Firefighting, which places similarly high physical demands on Industrial Firefighters. Although there are some studies on community firefighters, literature is scant on Industrial Firefighters and their physical fitness. ^ A cross-sectional study of Industrial Firefighters in Petrochemical companies in Texas was carried out in 1996–98 to assess their physical fitness and to develop a set of physical agility criteria useful in their selection and ongoing fitness for duty evaluations. ^ A physical agility criteria and a fitness scorecard was developed based on seven parameters (resting heart rate, diastolic blood pressure, aerobic capacity, muscle strength, muscle endurance, trunk flexibility and total body fat) of musculoskeletal and cardiorespiratory fitness. Each indicator received a minimum of 0 to a maximum of 20 points, based on individual performance. Therefore a minimum and maximum achievable score for the entire battery of tests was 0 and 140 respectively. Of the 111 study subjects, 5 (4.5%) were far above average, 31 (28%) above average, 46 (41.5 %) average, 29 (26%) below average and 0 (0%) far below average as deemed by the physical fitness scorecard. The mean score was 77 (±23) with a minimum and maximum score of 35 and 135 respectively. ^ Following univariate analysis an exploratory factor analysis to group variables and to assess the overall role of constituent variables in total fitness of a firefighter was developed. This was followed by a stepwise linear regression analysis using aerobic capacity as a dependent variable. ^ Finally, a graded implementation strategy was devised, such that all existing Industrial Firefighters would have an opportunity to improve or maintain their physical fitness at or above average level as deemed by the fitness scorecard. ^

Optimizing Performance of Conductive Nanoparticle-filled Membranes

Conductive membranes were prepared by magnetic alignment of graphite-coated iron nanoparticles (GCINs) in a polyisobutylene (PIB) matrix, which was cast onto an interdigitated surface electrode. Toluene and tetrahydrofuran (THF) were used as solvents for the casting solution. Different molecular weights of PIB and solutions with concentrations ranging from 0.05- to 50-wt% were explored to optimize the mechanical and physical properties of the membrane. The amount of GCINs used in the membranes ranged from 0.1- to 2.5-wt%, and a sonicator was used to disperse the particles in the membrane. Sedimentation and surfactant studies were conducted to investigate the dispersion of GCINs in solutions. Progresses were made to find an optimal combination of various parameters in order to attain thin homogenous membranes for fast response.

Performance recovery from exercise: A review from a statistical point of view

Background. Research into methods for recovery from fatigue due to exercise is a popular topic among sport medicine, kinesiology and physical therapy. However, both the quantity and quality of studies and a clear solution of recovery are lacking. An analysis of the statistical methods in the existing literature of performance recovery can enhance the quality of research and provide some guidance for future studies. Methods: A literature review was performed using SCOPUS, SPORTDiscus, MEDLINE, CINAHL, Cochrane Library and Science Citation Index Expanded databases to extract the studies related to performance recovery from exercise of human beings. Original studies and their statistical analysis for recovery methods including Active Recovery, Cryotherapy/Contrast Therapy, Massage Therapy, Diet/Ergogenics, and Rehydration were examined. Results: The review produces a Research Design and Statistical Method Analysis Summary. Conclusion: Research design and statistical methods can be improved by using the guideline from the Research Design and Statistical Method Analysis Summary. This summary table lists the potential issues and suggested solutions, such as, sample size calculation, sports specific and research design issues consideration, population and measure markers selection, statistical methods for different analytical requirements, equality of variance and normality of data, post hoc analyses and effect size calculation.^

AN EMPIRICAL ESTIMATION OF MEDICAL AND NON-MEDICAL INPUTS IN THE PRODUCTION OF CARDIO-RESPIRATORY PHYSICAL HEALTH STATUS

The purpose of this study was to examine, in the context of an economic model of health production, the relationship between inputs (health influencing activities) and fitness.^ Primary data were collected from 204 employees of a large insurance company at the time of their enrollment in an industrially-based health promotion program. The inputs of production included medical care use, exercise, smoking, drinking, eating, coronary disease history, and obesity. The variables of age, gender and education known to affect the production process were also examined. Two estimates of fitness were used; self-report and a physiologic estimate based on exercise treadmill performance. Ordinary least squares and two-stage least squares regression analyses were used to estimate the fitness production functions.^ In the production of self-reported fitness status the coefficients for the exercise, smoking, eating, and drinking production inputs, and the control variable of gender were statistically significant and possessed theoretically correct signs. In the production of physiologic fitness exercise, smoking and gender were statistically significant. Exercise and gender were theoretically consistent while smoking was not. Results are compared with previous analyses of health production. ^

The effects of ethnicity and ethnic composition of schools on physical activity and nutrition behaviors of 8th and 11th graders in Texas

With rates of obesity and overweight continuing to increase in the US, the attention of public health researchers has focused on nutrition and physical activity behaviors. However, attempts to explain the disparate rates of obesity and overweight between whites and Hispanics have often proven inadequate. Indeed, the nebulous term ‘ethnicity’ provides little important detail in addressing potential biological, behavioral, and environmental factors that may affect rates of obesity and overweight. In response to this, the present research seeks to test the explanatory powers of ethnicity by situating the nutrition and physical activity behaviors of whites and Hispanic into their broader social contexts. It is hypothesized that a student's gender and grade level, as well as the socioeconomic status and ethnic composition of their school, will have more predictive power for these behaviors than will self-reported ethnicity. ^ Analyses revealed that while ethnicity did not seem to impact nutrition behaviors among the wealthier schools and those with fewer Hispanics, ethnicity was relevant in explaining these behaviors in the poorest tertile of schools and those with the highest number of Hispanics. With respect to physical activity behaviors, the results were mixed. The variables representing regular physical activity, participation in extracurricular physical activities, and performance of strengthening and toning exercises were more likely to be determined by SES and ethnic composition than ethnicity, especially among 8th grade males. However, school sports team and physical education participation continued to vary by ethnicity, even after controlling for SES and ethnic composition of schools. In conclusion then, it is important to understand the intersecting demographic and social variables that define and surround the individual in order to understand nutrition and physical activity behaviors and thus overweight and obesity.^

Relationships of impulsivity and physical fighting history to alcohol -induced aggression in women

Research suggests women respond to the aggression-inducing effects of alcohol in a manner similar to men. Highly aggressive men are more prone to alcohol-induced aggression, but this relationship is less clear for women. This study examined whether alcohol consumption would differentially affect laboratory-measured aggression in a sample of aggressive and non-aggressive women and how those differences might be related to components of impulsive behavior. In 39 women recruited from the community (two groups: with and without histories of physical fighting) ages 21–40, laboratory aggressive behavior was assessed following placebo and 0.80 g/kg alcohol consumption (all women experienced both conditions). Baseline laboratory impulsive behavior of three impulsivity models was later assessed in the same women. In the aggression model (PSAP), participants were provoked by periodic subtractions of money, which were blamed on a fictitious partner. Aggression was operationalized as the responses the participant made to subtract money from that partner. The three components of impulsivity that were tested included: (1) response initiation (IMT/DMT), premature responses made prior to the completion of stimulus processing, (2) response inhibition (GoStop), a failure to inhibit an already initiated response, and (3) consequence sensitivity (SKIP and TCIP), the choice for a smaller-sooner reward over a larger-later reward. I hypothesized that, compared to women with no history of physical fighting, women with a history of physical fighting would exhibit higher rates of alcohol-induced laboratory aggression and higher rates of baseline impulsive responding (particularly for the IMT/DMT), which would also be related to the alcohol-induced increases aggression. Consistent with studies in men, the aggressive women showed strong associations between laboratory aggression and self-report measures, while the non-aggressive women did not. However, unlike men, following alcohol consumption it was the non-aggressive women's laboratory aggression that was related to their self-reports of aggression and impulsivity. Additionally, response initiation measures of impulsivity distinguished the two groups, while response inhibition and consequence sensitivity measures did not; commission error rates on the IMT/DMT were higher in the aggressive women compared to the non-aggressive women. Regression analyses of the behavioral measures showed no relationship between the aggression and impulsivity performance of the two groups. These results suggest that the behavioral (and potentially biological) mechanism underlying aggressive behavior of women is different than that of men. ^

Model results of ocean physical field of the reference state and the targets in NetCDF format

In a feasibility study, the potential of proxy data for the temperature and salinity during the Last Glacial Maximum (LGM, about 19 000 to 23 000 years before present) in constraining the strength of the Atlantic meridional overturning circulation (AMOC) with a general ocean circulation model was explored. The proxy data were simulated by drawing data from four different model simulations at the ocean sediment core locations of the Multiproxy Approach for the Reconstruction of the Glacial Ocean surface (MARGO) project, and perturbing these data with realistic noise estimates. The results suggest that our method has the potential to provide estimates of the past strength of the AMOC even from sparse data, but in general, paleo-sea-surface temperature data without additional prior knowledge about the ocean state during the LGM is not adequate to constrain the model. On the one hand, additional data in the deep-ocean and salinity data are shown to be highly important in estimating the LGM circulation. On the other hand, increasing the amount of surface data alone does not appear to be enough for better estimates. Finally, better initial guesses to start the state estimation procedure would greatly improve the performance of the method. Indeed, with a sufficiently good first guess, just the sea-surface temperature data from the MARGO project promise to be sufficient for reliable estimates of the strength of the AMOC.

Territorial quality and sustainable development : Indicators of performance in the context of a model for participatory rural tourism certification

El turismo rural ha sido incorporado por pequeños establecimientos agropecuarios del partido de Cnel. Suárez, provincia de Buenos Aires, Argentina, como actividad alternativa para mejorar la calidad de vida de sus miembros y superar situaciones de crisis agravadas por la marginalidad productiva del SO bonaerense, región a la que pertenecen. Bajo el programa Cambio Rural del INTA (Instituto Nacional de Tecnología Agropecuaria) conforman el Grupo 'Cortaderas II', junto a otros emprendedores interesados en valorar el medio rural. Han avanzado en el proceso de reconocimiento de su identidad y puesta en valor de recursos específicos con anclaje en el territorio. Esta identidad comienza a apreciarse internamente, a raíz de la dinámica grupal lograda y la incipiente articulación con otros actores para la construcción de un partenariado público y privado que genere sinergias y contribuya al desarrollo sustentable del territorio. Sin embargo, aún no es claramente percibida por el turista, cada vez más exigente. Por lo tanto, el presente trabajo persigue proponer indicadores para evaluar el desempeño de un Sistema de Gestión de Calidad con enfoque territorial que, adaptando el modelo europeo 'Marca de Calidad Territorial', sustente una estrategia comercial de diferenciación del servicio y simultáneamente, mida el progreso hacia una mejor calidad de vida y fortalecimiento de vínculos con la cultura local y el entorno físico-natural en el marco del desarrollo sustentable. La investigación se plantea para la micro escala, ya que se trata de un estudio de caso, relevándose información primaria mediante observación directa y entrevistas semi-estructuradas, complementada con información secundaria diagnóstica utilizada por INTA. Las características del grupo y su dinámica de funcionamiento bajo el programa Cambio Rural revelan que es posible adoptar un proceso de certificación participativa propuesto para cuatro pilares de la calidad: de Bienes y Servicios, Institucional, Social y Ambiental. El modelo se integra con indicadores de evaluación de desempeño, agrupados en áreas clave para cada una de las dimensiones de la sustentabilidad, que contemplan el paisaje y la gestión de los recursos naturales; el impacto económico de la actividad, la calidad de la oferta y satisfacción del turista; así como las relaciones sociales internas y los vínculos con otros actores del territorio. Principalmente se encontraron fortalezas en la búsqueda de partenariados y debilidades en aspectos de comunicación y promoción. Se considera que este sistema de herramientas de gestión sustentable permitiría superar las dificultades de una certificación individual, pudiendo aplicarse a emprendimientos con otra ubicación geográfica

Territorial quality and sustainable development : Indicators of performance in the context of a model for participatory rural tourism certification

El turismo rural ha sido incorporado por pequeños establecimientos agropecuarios del partido de Cnel. Suárez, provincia de Buenos Aires, Argentina, como actividad alternativa para mejorar la calidad de vida de sus miembros y superar situaciones de crisis agravadas por la marginalidad productiva del SO bonaerense, región a la que pertenecen. Bajo el programa Cambio Rural del INTA (Instituto Nacional de Tecnología Agropecuaria) conforman el Grupo 'Cortaderas II', junto a otros emprendedores interesados en valorar el medio rural. Han avanzado en el proceso de reconocimiento de su identidad y puesta en valor de recursos específicos con anclaje en el territorio. Esta identidad comienza a apreciarse internamente, a raíz de la dinámica grupal lograda y la incipiente articulación con otros actores para la construcción de un partenariado público y privado que genere sinergias y contribuya al desarrollo sustentable del territorio. Sin embargo, aún no es claramente percibida por el turista, cada vez más exigente. Por lo tanto, el presente trabajo persigue proponer indicadores para evaluar el desempeño de un Sistema de Gestión de Calidad con enfoque territorial que, adaptando el modelo europeo 'Marca de Calidad Territorial', sustente una estrategia comercial de diferenciación del servicio y simultáneamente, mida el progreso hacia una mejor calidad de vida y fortalecimiento de vínculos con la cultura local y el entorno físico-natural en el marco del desarrollo sustentable. La investigación se plantea para la micro escala, ya que se trata de un estudio de caso, relevándose información primaria mediante observación directa y entrevistas semi-estructuradas, complementada con información secundaria diagnóstica utilizada por INTA. Las características del grupo y su dinámica de funcionamiento bajo el programa Cambio Rural revelan que es posible adoptar un proceso de certificación participativa propuesto para cuatro pilares de la calidad: de Bienes y Servicios, Institucional, Social y Ambiental. El modelo se integra con indicadores de evaluación de desempeño, agrupados en áreas clave para cada una de las dimensiones de la sustentabilidad, que contemplan el paisaje y la gestión de los recursos naturales; el impacto económico de la actividad, la calidad de la oferta y satisfacción del turista; así como las relaciones sociales internas y los vínculos con otros actores del territorio. Principalmente se encontraron fortalezas en la búsqueda de partenariados y debilidades en aspectos de comunicación y promoción. Se considera que este sistema de herramientas de gestión sustentable permitiría superar las dificultades de una certificación individual, pudiendo aplicarse a emprendimientos con otra ubicación geográfica

Territorial quality and sustainable development : Indicators of performance in the context of a model for participatory rural tourism certification

El turismo rural ha sido incorporado por pequeños establecimientos agropecuarios del partido de Cnel. Suárez, provincia de Buenos Aires, Argentina, como actividad alternativa para mejorar la calidad de vida de sus miembros y superar situaciones de crisis agravadas por la marginalidad productiva del SO bonaerense, región a la que pertenecen. Bajo el programa Cambio Rural del INTA (Instituto Nacional de Tecnología Agropecuaria) conforman el Grupo 'Cortaderas II', junto a otros emprendedores interesados en valorar el medio rural. Han avanzado en el proceso de reconocimiento de su identidad y puesta en valor de recursos específicos con anclaje en el territorio. Esta identidad comienza a apreciarse internamente, a raíz de la dinámica grupal lograda y la incipiente articulación con otros actores para la construcción de un partenariado público y privado que genere sinergias y contribuya al desarrollo sustentable del territorio. Sin embargo, aún no es claramente percibida por el turista, cada vez más exigente. Por lo tanto, el presente trabajo persigue proponer indicadores para evaluar el desempeño de un Sistema de Gestión de Calidad con enfoque territorial que, adaptando el modelo europeo 'Marca de Calidad Territorial', sustente una estrategia comercial de diferenciación del servicio y simultáneamente, mida el progreso hacia una mejor calidad de vida y fortalecimiento de vínculos con la cultura local y el entorno físico-natural en el marco del desarrollo sustentable. La investigación se plantea para la micro escala, ya que se trata de un estudio de caso, relevándose información primaria mediante observación directa y entrevistas semi-estructuradas, complementada con información secundaria diagnóstica utilizada por INTA. Las características del grupo y su dinámica de funcionamiento bajo el programa Cambio Rural revelan que es posible adoptar un proceso de certificación participativa propuesto para cuatro pilares de la calidad: de Bienes y Servicios, Institucional, Social y Ambiental. El modelo se integra con indicadores de evaluación de desempeño, agrupados en áreas clave para cada una de las dimensiones de la sustentabilidad, que contemplan el paisaje y la gestión de los recursos naturales; el impacto económico de la actividad, la calidad de la oferta y satisfacción del turista; así como las relaciones sociales internas y los vínculos con otros actores del territorio. Principalmente se encontraron fortalezas en la búsqueda de partenariados y debilidades en aspectos de comunicación y promoción. Se considera que este sistema de herramientas de gestión sustentable permitiría superar las dificultades de una certificación individual, pudiendo aplicarse a emprendimientos con otra ubicación geográfica