Efectos de un programa de actividad física extracurricular en niños de primer ciclo de ESO con sobrepeso y obesidad

Obesity and its impact are increasingly obvious in Spanish society. Thus, the purpose of this study was to investigate the effectiveness of an extracurricular intervention of physical and sports activities in order to improve students' body composition and fitness level between two groups of adolescences with overweight or obesity for a six-month period. Moreover, a comparison based on gender was also targeted in this intervention. The sample consisted of 38 students, seventeen boys and twenty-one girls, with BMI above the 85th percentile. Several fitness tests and anthropometric measurements were performed. The results showed significant improvements in the experimental group regarding their physical condition and body fat percentage compared to the control group who did not show any significant achievements. According to the comparison based on gender, within the experimental group, girls achieved more significant results both in their physical fitness and in their body fat percentage

A Compact Array Transducer for Full Calibration of Underwater Acoustic Detection Neutrino Telescopes

[EN] KM3NeT, the underwater neutrino telescope in the Mediterranean Sea, is a detector under construction. KM3NeT uses Digital Optical Modules (DOMs) to detect neutrinos but there will be a study about the viability to acoustic detection of neutrinos using mainly the acoustic sensors the telescope has for positioning purposes. For this, it is necessary to calibrate and test the acoustic response of the receivers in the detector to determine the sensitivity to detect the neutrino acoustic signal and discriminate it from the environmental background. In this work, the strategy for the calibration of the sensor system using a compact array using three steps (frequency, directivity and neutrino signal-like) is described. Moreover, some R&D activities and results about the second step (long parametric directive signals) are shown.Financial support of the Spanish Plan Estatal de Investigación, ref. PGC2018-096663-B-C43 (MICINN/FEDER)Ardid Ramírez, M.; Tortosa, DD.; Martínez Mora, JA. (2019). A Compact Array Transducer for Full Calibration of Underwater Acoustic Detection Neutrino Telescopes. IEEE. 591-595. https://doi.org/10.1109/IOTSMS48152.2019.8939244S59159

Within-subject variation in the Cognitive Timed Up and Go test as an explanatory variable in fall risk in patients with Parkinson’s disease

Objective: To explore the use of within-subject variation in the Cognitive Timed Up and Go test (Cognitive TUGwsv) as an explanatory variable in fall risk in the Parkinson’s disease population. Design: Cross-sectional study. Methods: Fifty-three patients with Parkinson’s disease completed 3 trials of the Cognitive TUGwsv. Within-subject variation was calculated using the standard deviation of an individual’s repeated measurements, and compared on the basis of the fall history reported in the previous 6 months. Participants who reported < 2 falls were classified as “non-recurrent fallers” (n = 31) and those who reported ≥ 2 falls were classified as “recurrent fallers” (n = 22). Univariate and a multivariate logistic regression were used to investigate the statistical impact of the Cognitive TUGwsv as an explanatory variable in fall risk. Discriminative ability and cut-off score were determined based on receiver operating characteristic analysis. Results: There was a significant difference between groups in the Cognitive TUGwsv (p = 0.002). Univariate logistic regression indicated a significant association between Cognitive TUGwsv and fall risk (χ2=12.365, p < 0.001), with an odds ratio of 2.5 (95% confidence interval (95% CI) = 1.34–4.65). Multivariate logistic regression showed that body mass index (BMI), Falls Efficacy Scale-International (FES-I), Cognitive TUGwsv, and the mean velocity of the centre of foot pressure (Closed Eyes) (Velocity COP (CE)) were significant explanatory variables in fall risk. Cognitive TUGwsv was the most important independent variable. Receiver operating characteristic analysis revealed an acceptable discriminative power (area under the curve (AUC) = 0.757, 95% CI = 0.619–0.864, p < 0.001) and a cut-off point of 1.53 s. Conclusion: A higher Cognitive TUGwsv correlated with higher fall risk. Thus, diagnostic tests and exercise programmes could consider Cognitive TUGwsv when assessing fall risk in the Parkinson’s disease population.Sergio Sebastiá-Amat participated in this study supported by a pre-doctoral grant (ACIF/2018/209) from the Generalitat Valenciana, Spain

Influence of Abdominal Hollowing Maneuver on the Core Musculature Activation during the Prone Plank Exercise

This cross-sectional study of repeated measures investigated whether integrating the abdominal hollowing maneuver (AHM) into the prone plank performance is an effective strategy for increasing both the activation of the deep and superficial core musculature. Electromyographical (EMG) responses of rectus abdominis (RA), external oblique (EO), internal oblique (IO), and lumbar erector spinae (LES), and ratings of perceived exertion (RPE) of 20 participants (13 male, 7 female; mean ± standard deviation (SD) age: 24.25 ± 3.54 years; body mass: 66.42 ± 8.40 kg; height: 1.70 ± 9.51 m) were compared across two experimental conditions: the traditional prone plank (STANDARD); and a variation including the AHM (HOLLOWING). Regarding Total Intensity, HOLLOWING resulted in significantly greater EMG response than STANDARD (p < 0.001; Effect size (ES) = 3.01). Specifically, RA showed no significant differences between STANDARD and HOLLOWING (p = 0.056; ES = 0.285). However, for the remaining analyzed muscles, HOLLOWING significantly provided higher EMG activation compared to STANDARD (LES: p = 0.004; ES = 0.619; left EO: p < 0.001; ES = 1.031; right EO: p < 0.001; ES = 1.419; left IO: p < 0.001; ES = 2.021; right IO: p < 0.001; ES = 2.269). Regarding RPE, HOLLOWING reported values significantly greater than STANDARD (p < 0.001; ES = 2.94). In conclusion, integrating the AHM into the prone plank exercise enhances overall abdominal activity, particularly in both obliques. These findings provide updated guidelines for lumbar stabilization and core strengthening in health-related physical fitness programs.This research was funded by Consellería de Educación, Investigación, Cultura y Deporte de la Generalitat Valenciana, and European Social Fund (European Union), grant project number ACIF/2016/048

Rail corrugation growth accounting for the flexibility and rotation of the wheel set and the non-Hertzian and non-steady-state effects at contact patch

[EN] In this work, a simulation tool is developed to analyse the growth of rail corrugation consisting of several models connected in a feedback loop in order to account for both the short-term dynamic vehicle track interaction and the long-term damage. The time-domain vehicle track interaction model comprises a flexible rotating wheel set model, a cyclic track model based on a substructuring technique and a non-Hertzian and non-steady-state three-dimensional wheel rail contact model, based on the variational theory by Kalker. Wear calculation is performed with Archard s wear model by using the contact parameters obtained with the non-Hertzian and non-steady-state three-dimensional contact model. The aim of this paper is to analyse the influence of the excitation of two coinciding resonances of the flexible rotating wheel set on the rail corrugation growth in the frequency range from 20 to 1500 Hz, when contact conditions similar to those that can arise while a wheel set is negotiating a gentle curve are simulated. Numerical results show that rail corrugation grows only on the low rail for two cases in which two different modes of the rotating wheel set coincide in frequency. In the first case, identified by using the Campbell diagram, the excitation of both the backward wheel mode and the forward third bending mode of the wheel set model (B-F modes) promotes the growth of rail corrugation with a wavelength of 110mm for a vehicle velocity of 142 km/h. In the second case, the excitation of both the backward wheel mode and the backward third bending mode (B-B modes) gives rise to rail corrugation growth at a wavelength of 156 mm when the vehicle velocity is 198 km/h.The authors acknowledge the financial contribution by the Spanish Ministry of Economy and Competitiveness through the project TRA2010-15669.Vila Tortosa, MP.; Baeza González, LM.; Martínez Casas, J.; Carballeira, J. (2014). Rail corrugation growth accounting for the flexibility and rotation of the wheel set and the non-Hertzian and non-steady-state effects at contact patch. Vehicle System Dynamics. 52:92-108. https://doi.org/10.1080/00423114.2014.881513S9210852Grassie, S. L., & Kalousek, J. (1993). Rail Corrugation: Characteristics, Causes and Treatments. Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 207(1), 57-68. doi:10.1243/pime_proc_1993_207_227_02Hempelmann, K., Hiss, F., Knothe, K., & Ripke, B. (1991). The formation of wear patterns on rail tread. Wear, 144(1-2), 179-195. doi:10.1016/0043-1648(91)90014-lHempelmann, K., & Knothe, K. (1996). An extended linear model for the prediction of short pitch corrugation. Wear, 191(1-2), 161-169. doi:10.1016/0043-1648(95)06747-7GRASSIE, S. L., & ELKINS, J. A. (1998). RAIL CORRUGATION ON NORTH AMERICAN TRANSIT SYSTEMS. Vehicle System Dynamics, 29(sup1), 5-17. doi:10.1080/00423119808969548Egana, J. I., Vinolas, J., & Seco, M. (2006). Investigation of the influence of rail pad stiffness on rail corrugation on a transit system. Wear, 261(2), 216-224. doi:10.1016/j.wear.2005.10.004Igeland, A. (1996). Railhead Corrugation Growth Explained by Dynamic Interaction between Track and Bogie Wheelsets. Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 210(1), 11-20. doi:10.1243/pime_proc_1996_210_322_02Gómez, I., & Vadillo, E. G. (2003). A linear model to explain short pitch corrugation on rails. Wear, 255(7-12), 1127-1142. doi:10.1016/s0043-1648(03)00282-5Collette, C., Vanhonacker, P., Bastaits, R., & Levy, D. (2008). Comparison between time and frequency studies of a corrugated curve of RER Paris network. Wear, 265(9-10), 1249-1258. doi:10.1016/j.wear.2008.01.030Daniel, W. J. T., Horwood, R. J., Meehan, P. A., & Wheatley, N. (2008). Analysis of rail corrugation in cornering. Wear, 265(9-10), 1183-1192. doi:10.1016/j.wear.2008.02.030Fayos, J., Baeza, L., Denia, F. D., & Tarancón, J. E. (2007). An Eulerian coordinate-based method for analysing the structural vibrations of a solid of revolution rotating about its main axis. Journal of Sound and Vibration, 306(3-5), 618-635. doi:10.1016/j.jsv.2007.05.051Baeza, L., & Ouyang, H. (2011). A railway track dynamics model based on modal substructuring and a cyclic boundary condition. Journal of Sound and Vibration, 330(1), 75-86. doi:10.1016/j.jsv.2010.07.023Kalker, J. J. (1990). Three-Dimensional Elastic Bodies in Rolling Contact. Solid Mechanics and Its Applications. doi:10.1007/978-94-015-7889-9Xie, G., & Iwnicki, S. D. (2008). Simulation of wear on a rough rail using a time-domain wheel–track interaction model. Wear, 265(11-12), 1572-1583. doi:10.1016/j.wear.2008.03.016Igeland, A., & Ilias, H. (1997). Rail head corrugation growth predictions based on non-linear high frequency vehicle/track interaction. Wear, 213(1-2), 90-97. doi:10.1016/s0043-1648(97)00172-5Vila, P., Fayos, J., & Baeza, L. (2011). Simulation of the evolution of rail corrugation using a rotating flexible wheelset model. Vehicle System Dynamics, 49(11), 1749-1769. doi:10.1080/00423114.2011.552619Popp, K., Kruse, H., & Kaiser, I. (1999). Vehicle-Track Dynamics in the Mid-Frequency Range. Vehicle System Dynamics, 31(5-6), 423-464. doi:10.1076/vesd.31.5.423.8363Johnson, K. L. (1985). Contact Mechanics. doi:10.1017/cbo9781139171731Hiensch, M., Nielsen, J. C. O., & Verheijen, E. (2002). Rail corrugation in The Netherlands—measurements and simulations. Wear, 253(1-2), 140-149. doi:10.1016/s0043-1648(02)00093-5Jin, X., Xiao, X., Wen, Z., Guo, J., & Zhu, M. (2009). An investigation into the effect of train curving on wear and contact stresses of wheel and rail. Tribology International, 42(3), 475-490. doi:10.1016/j.triboint.2008.08.004Ilias, H., & Müller, S. (1994). A discrete-continuous track-model for wheelsets rolling over short wavelength sinusoidal rail irregularities. Vehicle System Dynamics, 23(sup1), 221-233. doi:10.1080/0042311930896951

Development of a trigger for acoustic neutrino candidates in KM3NeT

The KM3NeT Collaboration is constructing two large neutrino detectors in the Mediterranean Sea: ARCA, located near Sicily and aiming at neutrino astronomy, and ORCA located near Toulon and designed for the study of intrinsic neutrino properties. The two detectors together will have hundreds of Detection Units with Digital Optical Modules kept vertically by buoyancy forming a large 3D optical array for detecting the Cherenkov light produced after the neutrino interactions. To properly reconstruct the direction of the incoming neutrino, the position of the DOMs, which are not static due to the sea currents, must be monitored. For this purpose, the detector is equipped with an Acoustic Positioning System, which is composed of fixed acoustic emitters on the sea bottom, a hydrophone in each DU base, and a piezoceramic sensor in each DOM, as acoustic receivers. This network of acoustic sensors can be used not only for positioning, but also for acoustic monitoring studies such as bioacoustics, ship noise monitoring, environmental noise control, and acoustic neutrinos detection. This work explores the possibility of creating a trigger for saving the data for ultra-high-energy neutrino candidates detected acoustically by the hydrophones. The acoustic signal caused by the neutrino interaction in a fluid is a short-time duration Bipolar Pulse extremely directive and with a Fourier transform extending over a wide range of frequencies. A study of signal detection, has been done by simulating BP produced by the interaction of a UHE neutrino at 1 km from the detector at zero-degree incidence added to the experimental real acoustic data. Finally, a trigger proposal has been developed in order to record candidates of BPs and it has been tested. The number of candidates per second, precision, and recall have been monitored according to the cuts applied and parameters calculated by the algorithm.Comment: 9th International Workshop on Acoustic and Radio EeV Neutrino Detection Activities - ARENA202

Underwater Acoustic Positioning System for the Monitoring of KM3NeT Optical Modules

[EN] KM3NeT, the underwater neutrino telescope in the Mediterranean Sea, is a detector under construction. KM3NeT uses Digital Optical Modules (DOMs) to detect neutrinos by detecting the Cherenkov light of relativistic particles produced in the interaction. To reconstruct the neutrino event and the coming direction, it is necessary to monitor the position of each DOM, which is not fixed since it is mounted in flexible string lines, held close to vertical by buoys but sensitive to sea currents. A piezo-ceramic transducer is installed inside of each DOM. Using some emitters anchored in the sea floor it is possible to calculate the position of the DOMs by triangulation of distances obtained from the determination of the time of flight of the acoustic wave. In this work, the acoustic model used for the simulation of the system is described and the results presented.[ES] KM3NeT, el detector submarino que se encuentra en construcción en el Mar Mediterráneo, usa Módulos Digitales Ópticos (DOMs) para localizar neutrinos, a través de la detección de la luz de Cherenkov producida por partículas relativistas durante la interacción con el agua. Para reconstruir el camino seguido por el neutrino, es necesario saber la posición de cada DOM, el cuál no se encuentra fijo ya que está sujeto a unos cables anclados que se mantienen en vertical gracias a una boya en el final de la línea, lo cual la hace sensible al movimiento de las corrientes marinas. Cada DOM contiene instalada una cerámica piezoeléctrica, como receptor acústico, y usando unos emisores anclados en el fondo del mar se puede estimar la posición de cada DOM triangulando las distancias entre ellos, las cuales se saben por el tiempo de vuelo de la señal acústica. En este trabajo, se presenta una simulación del sistema y se describe el modelo acústico usado.Ardid Ramírez, M.; Bou Cabo, M.; D. Tortosa, D.; Martínez Mora, JA.; Poirè, C. (2019). Underwater Acoustic Positioning System for the Monitoring of KM3NeT Optical Modules. Revista de Acústica. 50(3-4):24-33. http://hdl.handle.net/10251/160009S2433503-

Ejercicio físico para personas con demencia y deterioro cognitivo leve: consideraciones metodológicas

The exponential worldwide increase in the number of older adults is causing a parallel rise in the number of cases of neurodegenerative diseases, such as mild cognitive impairment (MCI) and dementia. Exercise is a promising strategy for improving physical and cognitive function in healthy older adults, reducing the risk of developing MCI and dementia, and improving physical and cognitive function as well as decreasing neuropsychiatric symptoms in people with MCI and dementia. However, there are still some inconsistencies in the literature, especially in regards to the cognitive benefits, and there are currently no guidelines for prescribing exercise for older adults with cognitive impairment. In this article, a narrative review on the benefits of exercise for people with MCI and dementia was conducted, establishing some preliminary guidelines for prescribing exercise efficiently and safely in this population.El incremento exponencial del número de personas mayores a nivel mundial, está causando un aumento paralelo en el número de casos de enfermedades neurodegenerativas, como es el caso del deterioro cognitivo leve (DCL) o la demencia. El ejercicio físico es una estrategia prometedora para mejorar la función física y cognitiva de los adultos mayores sanos, reducir el riesgo de desarrollar un DCL o una demencia, así como mejorar la función física, cognitiva y los síntomas neuropsiquiátricos en personas con DCL o demencia. Sin embargo, existen todavía algunas inconsistencias en la literatura científica, especialmente acerca de los beneficios cognitivos, y faltan pautas metodológicas para prescribir ejercicio físico para personas mayores con deterioro cognitivo. En este artículo, se ha llevado a cabo una revisión narrativa de la literatura acerca de los beneficios del ejercicio físico para personas con DCL y demencia, estableciendo unas pautas metodológicas preliminares para prescribir ejercicio físico, de forma eficiente y segura en esta población.Miguel García-Jaén participated in this study supported by a pre-doctoral grant ACIF/2016/048 from the Generalitat Valenciana, Spain

Acute Effects of ACL Injury-Prevention Warm-Up and Soccer-Specific Fatigue Protocol on Dynamic Knee Valgus in Youth Male Soccer Players

Childhood anterior cruciate ligament (ACL) injuries—which can pose a major risk to a child’s sporting career—have been on the rise in the last few decades. Dynamic knee valgus (DKV) has been linked to an increased risk of ACL injury. Therefore, the aim of this study was to analyze the acute effects of an ACL injury prevention protocol (ACL-IPP) and a soccer-specific fatigue protocol (SSFP) on DKV in youth male soccer players. The research hypothesis was that DKV would be reduced by the ACL-IPP and increased by the SSFP. Eighteen youth male soccer players were divided according to baseline DKV. Those with moderate or large DKV performed a neuromuscular training protocol based on activation of the abductor and external rotator hip muscles. Those with little or no DKV performed a soccer-specific fatigue protocol. DKV was assessed using the single-leg squat pre- and post-protocols in both legs. The ACL-IPP significantly decreased DKV during single-leg squat (p < 0.01, effect size = 1.39), while the SSFP significantly increased baseline DKV in the dominant leg during single-leg squat (p = 0.012; effect size = 1.74). In conclusion, the ACL-IPP appears to acutely reduce the DKV in youth male soccer players, and the SSFP seems to acutely increase the DKV in those players who showed a light or no DKV in a non-fatigue situation. By using the SSFP, it may be possible to determine which players would benefit from injury prevention programs due to increased DKV during game scenarios, while hip abductor and external rotator neuromuscular training may be beneficial for players who have moderate and severe DKV during single-leg squat under non-fatigued scenarios

Acoustic parametric techniques for neutrino telescopes

[EN] In this work, we present a compact transmitter array based on the parametric acoustic sources effect able to reproduce the acoustic signature of an Ultra-High Energy neutrino interaction in water. We also propose to use directive transducers using the parametric technique for the characterization of piezo-ceramic sensors contained in the KM3NeT DOMs. This technique can minimize the need for an anechoic tank.Ardid Ramírez, M.; Tortosa, DD.; Llorens Alvarez, CD.; Martínez Mora, JA.; Saldaña-Coscollar, M. (2019). Acoustic parametric techniques for neutrino telescopes. EPJ Web of Conferences (Online). 216:1-3. https://doi.org/10.1051/epjconf/201921604001S13216Saldana M., PhD Thesis, Acoustic System Development for Neutrino Underwater Detectors. Gandia: Universitat Politecnica de Valencia (2017)Buis E.J.; et al. Characterization of the KM3NeT hydrophone. ARENA2018 this issue