Post-season detraining effects on physiological and performance parameters in top-level kayakers: comparison of two recovery strategies

This study analyzed changes in physiological parameters, hormonal markers and kayaking performance following 5-wk of reduced training (RT) or complete training cessation (TC). Fourteen top-level male kayakers were randomly assigned to either a TC (n = 7) or RT group (n = 7) at the end of their competitive season (T1). Subjects undertook blood sampling and an incremental test to exhaustion on a kayak ergometer at T1 and again following 5 weeks of RT or TC (T2). Maximal oxygen uptake (VO(2)max) and oxygen uptake at second ventilatory threshold (VT2) significantly decreased following TC (-10.1% and -8.8%, respectively). Significant decreases were also observed in RT group but to a lesser extent (-4.8% and -5.7% respectively). Heart rate at VT2 showed significant increases following TC (3.5%). However, no changes, were detected in heart rate at VO(2)max in any group. Peak blood lactate remained unchanged in both groups at T2. Paddling speed at VO(2)max declined significantly at T2 in the TC group (-3.3%), while paddling speed at VT2 declined significantly in both groups (-5.0% and -4.2% for TC and RT, respectively). Stroke rate at VO(2)max and at VT2 increased significantly only following TC by 5.2% and 4.9%, respectively. Paddling power at VO(2)max and at VT2 decreased significantly in both groups although the values observed following RT were higher than those observed following TC. A significant decline in cortisol levels (-30%) was observed in both groups, while a higher increase in testosterone to cortisol ratio was detected in the RT group. These results indicate that a RT strategy may be more effective than complete TC in order to avoid excessive declines in cardiovascular function and kayaking performance in top-level paddlers

Real-Time Monitoring System for a Utility-Scale Photovoltaic Power Plant

There is, at present, considerable interest in the storage and dispatchability of photovoltaic (PV) energy, together with the need to manage power flows in real-time. This paper presents a new system, PV-on time, which has been developed to supervise the operating mode of a Grid-Connected Utility-Scale PV Power Plant in order to ensure the reliability and continuity of its supply. This system presents an architecture of acquisition devices, including wireless sensors distributed around the plant, which measure the required information. It is also equipped with a high-precision protocol for synchronizing all data acquisition equipment, something that is necessary for correctly establishing relationships among events in the plant. Moreover, a system for monitoring and supervising all of the distributed devices, as well as for the real-time treatment of all the registered information, is presented. Performances were analyzed in a 400 kW transformation center belonging to a 6.1 MW Utility-Scale PV Power Plant. In addition to monitoring the performance of all of the PV plant’s components and detecting any failures or deviations in production, this system enables users to control the power quality of the signal injected and the influence of the installation on the distribution grid

Monitoring of Energy Data with Seamless Temporal Accuracy Based on the Time-Sensitive Networking Standard and Enhanced μPMUs

In the energy sector, distributed synchronism and a high degree of stability are necessary for all real-time monitoring and control systems. Instantaneous response to critical situations is essential for the integration of renewable energies. The most widely used standards for clock synchronisation, such as Network Time Protocol (NTP) and Precision Time Protocol (PTP), do not allow for achieving synchronised simultaneous sampling in distributed systems. In this work, a novel distributed synchronism system based on the Time-Sensitive Networking (TSN) standard has been validated for its integration in an architecture oriented towards the high-resolution digitisation of photovoltaic (PV) generation systems. This method guarantees a time stamping with an optimal resolution that allows for the analysis of the influence of fast-evolving atmospheric fluctuations in several plants located in the same geographical area. This paper proposes an enhanced micro-phasor measurement unit (μPMU) that acts as a phasor meter and TSN master controlling the monitoring system synchronism. With this technique, the synchronism would be extended to the remaining measurement systems that would be involved in the installation at distances greater than 100 m. Several analyses were carried out with an on-line topology of four acquisition systems capturing simultaneously. The influence of the Ethernet network and the transducers involved in the acquisition process were studied. Tests were performed with Ethernet cable lengths of 2, 10, 50, and 75 m. The results were validated with 24-bit Sigma-Delta converters and high-precision resistor networks specialised in high-voltage monitoring. It was observed that with an appropriate choice of sensors and TSN synchronism, phase errors of less than ±1μs can be guaranteed by performing distributed captures up to 50 kS/s. Statistical analysis showed that uncertainties of less than ±100 ns were achieved with 16-bit Successive Approximation Register (SAR) converters at a moderate cost. Finally, the requirements of the IEEE C37.118.1-2011 standard for phasor measurement units (PMU) were also satisfied. This standard establishes an uncertainty of ±3.1 μs for 50 Hz systems. These results demonstrate the feasibility of implementing a simultaneous sampling system for distributed acquisition systems coordinated by a μPMU

Can Our Fingers Alone Raise Us Up to the Sky? Analysis of the Digit Ratio Association with Success in Olympic Wrestling

The aim of this study is to analyse the contribution of the second to fourth digit ratio (2D:4D) to success in wrestling. A total of 180 elite wrestlers who participated in the 2011 Spanish Wrestling Championship took part in this study (132 men, 23.6±6.1 years old; 48 women, 21.7±4.9 years old). Prior to competition, wrestlers were interviewed about their years of training experience and their hands were scanned. 2D:4D was calculated using computer-assisted image analysis. A multinomial logistic regression coefficient to calculate odd ratios (OR’s) and 95% confidence intervals (CI’s) were established to determine the contribution of digit ratio and training experience to success in Olympic wrestling. Additionally, mean and median analyses were calculated between males and females, and between successful and non-successful wrestlers in order to establish differences in 2D:4D and training experience between these groups. There were no differences between successful and non-successful wrestlers in 2D:4D (p=0.87 for right hand, and p=0.46 for left hand), whereas having high training experience supposed an increase up to 4.38 (1.70 – 11.01) times more likely to be successful. Our results suggest that 2D:4D fails in predicting wrestling success, whereas training background is a good predictor of competition prowess in highly trained wrestlers

An Embedded System in Smart Inverters for Power Quality and Safety Functionality

The electricity sector is undergoing an evolution that demands the development of a network model with a high level of intelligence, known as a Smart Grid. One of the factors accelerating these changes is the development and implementation of renewable energy. In particular, increased photovoltaic generation can affect the network’s stability. One line of action is to provide inverters with a management capacity that enables them to act upon the grid in order to compensate for these problems. This paper describes the design and development of a prototype embedded system able to integrate with a photovoltaic inverter and provide it with multifunctional ability in order to analyze power quality and operate with protection. The most important subsystems of this prototype are described, indicating their operating fundamentals. This prototype has been tested with class A protocols according to IEC 61000-4-30 and IEC 62586-2. Tests have also been carried out to validate the response time in generating orders and alarm signals for protections. The highlights of these experimental results are discussed. Some descriptive aspects of the integration of the prototype in an experimental smart inverter are also commented upon

Diferencias en la condición física en niños de entornos rurales y urbanos

The aim of this work is to study the relationship between health related physical fitness and residence context in samples of school children. A total of 293 students took part in the study (137 boys and 156 girls). After receiving the informed consent, we assessed health related physical fitness through an abbreviated version of the Eurofit Battery test that included BMI, horizontal jump, Sit and Reach test (flexibility), hand grip strength, and 20 metre shuttle run. To establish the relationship between the different variables, we conducted a statistical analysis using the Kolmogorov-Smirnov test and one t test for independent samples. In this study school children living in rural areas are fitter in comparison with the ones living in urban areas

Factores físicos y psicológicos predictores del éxito en lucha olímpica

This study was undertaken to analyse differences in physical, psychological and anthropometric markers related to success in olympic wrestling. Thirty seven male Freestyle and Greco-Roman wrestlers were assigned to two groups according to their competitive level: Elite (n = 18) and Amateur (n = 19). All the subjects underwent an anthropometric assessment, a complete physical fitness test battery (maximal dynamic and isometric strength, muscle power output, crank-arm wingate test, running speed and hamstring extensibility) as well as a psychological characteristics assessment associated with sport performance through the Psychological Performance Inventory. The elite wrestlers were older, had more training experience, a fat free mass, maximal dynamic and isometric strength, muscle power, mean and peak power during wingate testing and significantly higher self- perceptions of self-control, attitude control and the total average of the sum of all the scales. These results suggest that the optimisation of neuromuscular and anaerobic metabolism and several psychological performance markers are conditional and thus predictive of success in wrestling

Cellular Responses in Human Dental Pulp Stem Cells Treated with Three Endodontic Materials

Human dental pulp stem cells (HDPSCs) are of special relevance in future regenerative dental therapies. Characterizing cytotoxicity and genotoxicity produced by endodontic materials is required to evaluate the potential for regeneration of injured tissues in future strategies combining regenerative and root canal therapies. This study explores the cytotoxicity and genotoxicity mediated by oxidative stress of three endodontic materials that are widely used on HDPSCs: a mineral trioxide aggregate (MTA-Angelus white), an epoxy resin sealant (AH-Plus cement), and an MTA-based cement sealer (MTA-Fillapex). Cell viability and cell death rate were assessed by flow cytometry. Oxidative stress was measured by OxyBlot. Levels of antioxidant enzymes were evaluated by Western blot. Genotoxicity was studied by quantifying the expression levels of DNA damage sensors such as ATM and RAD53 genes and DNA damage repair sensors such as RAD51 and PARP-1. Results indicate that AH-Plus increased apoptosis, oxidative stress, and genotoxicity markers in HDPSCs. MTA-Fillapex was the most cytotoxic oxidative stress inductor and genotoxic material for HDPSCs at longer times in preincubated cell culture medium, and MTA-Angelus was less cytotoxic and genotoxic than AH-Plus and MTA-Fillapex at all times assayed

Methodologies and effects of weight cutting approaches in Olympic Wrestling: a review

La Lucha fue un deporte fundamental en los Juegos Olímpicos antiguos y todavía hoy sigue siendo una de las modalidades más populares en el Juegos Olímpico modernos. Actualmente, la Lucha Olímpica es un deporte de combate basado en un sistema de categorías por pesos que trata de equilibrar el potencial físico entre rivales, y por consiguiente aumentar el porcentaje del rendimiento que depende de las habilidades técnico-tácticas y psicológicas que cada luchador demuestra sobre el tapiz. Este sistema de categorías por peso obliga a todos los luchadores a cumplir o “dar el peso” unas pocas horas antes del comienzo del torneo, por lo que a lo largo de las últimas décadas los luchadores han puesto en práctica numerosas estrategias y metodologías de reducción de la masa corporal de cara a este pesaje oficial. En esta revisión se describirán pormenorizadamente estas metodologías de pérdida abrupta de masa corporal, así como los efectos que estas estrategias tienen sobre el rendimiento físico de los luchadores. Igualmente, y en base a evidencias científicas, se realizarán propuestas de adecuación y actualización de este reglamento oficial, considerado por la mayor parte de los científicos y técnicos relacionados con esta modalidad como parcialmente desfasado y en ocasiones irracional.Wrestling was an important part of the ancient Olympic Games and is still one of the more popular events of the modern Olympic Games. Nowadays, this combat sport is based on a weight class system which aims to balance out the physical characteristics between wrestlers and therefore increase the percentage of performance that depends on technical and psychological skills. This weight class system requires all wrestlers to "make weight" few hours before the tournament begins, so that over the last decades the wrestlers have implemented numerous kinds of weight cutting approaches before the official weighing. In this review the authors aim to perform a detailed description of these weight cutting strategies and their effects on the physical fitness performance of the wrestlers Furthermore, and based on scientific data, there will be proposals for adapting and updating these official rules, considered by most scientists and coaches as partially outdated and sometimes irrational.peerReviewe

AMIGaS - Motivational Activities for Gender Equality in STEM

En el marco del proyecto de innovación docente, se han realizado una serie de actividades de promoción de la mujer en estudios y empleos de disciplinas STEM, acrónimo de los términos en inglés Science, Technology, Engineering and Mathematics (Ciencia, Tecnología, Ingeniería y Matemáticas). El objetivo ha sido contribuir a que las mujeres puedan obtener mejores oportunidades de trabajo y no se mantengan alejadas de los cambios económicos y sociales que conllevará la industria del futuro, marcada por la convergencia de tecnologías digitales, físicas y biológicas, y que cambiará el mundo tal y como lo conocemos. Para ello se han realizado una serie de seminarios que han consistido en apoyar la participación de mujeres en el ámbito científico-tecnológico. Consiguiendo una concepción del alumnado femenino de las disciplinas de Ciencia e Ingeniería sobre el trabajo que desempeñan mujeres cuyas trayectorias profesionales son de alta relevancia en el ámbito tecnológico. Con esta propuesta se ha contribuido a la lucha contra los estereotipos y que el acceso de la mujer a estas materias crezca al mismo nivel al que es demandado, ya que la tecnología se encuentra en todos los niveles de la sociedad actual.Within the framework of the educational innovation project, a series of activities have been carried out to promote women in studies and jobs in STEM disciplines, an acronym for Science, Technology, Engineering, and Mathematics. The aim has been to help women to obtain better job opportunities and not to stay away from the economic and social changes that the industry of the future, marked by the convergence of digital, physical and biological technologies, will bring, will bring, and will change the world as we know it. To this end, a series of seminars have been held which have consisted of supporting the participation of women in the scientific-technological field. Achieving a conception of the female student body of the disciplines of Science and Engineering on the work carried out by women whose professional trajectories are of high relevance in the technological field. This proposal has contributed to the fight against stereotypes and to ensure that women's access to these subjects grows to the same level as that at which they are demanded since technology is found at all levels of today's society