Assessment of hormonal parameters in long-term karate Practitioners

Introduction: Karate is a Japanese martial art which is widely practiced in the Western world as a form of self-defense, as well as a discipline to achieve physical and mental balance.However, little is known with respect to its specific psychobiological effects, particularly in relation to the influence that karate may exert on the endocrine system. Thus, in the present study we analyzed the effects of regular karate practice on several hormonal parameters. Methods: 27 healthy volunteer subjects participated in the study, of whom 15 were allocated to the experimental group, and 12 were assigned to the control group. Experimental subjects were karate players with a minimum of 3 years of practice in this discipline. Blood samples for the quantification of hormonal parameters (TSH, T3, T4, PTH, ACTH, cortisol, and DHEA) were taken in both groups. To compare the means of the control and experimental group, a t-test for independent groups was performed in each dependent variable. Results: Significant differences between the experimental and control group were found in T3, T4, and cortisol, with karate players showing lower blood levels of these hormones than control. Conclusions: These findings reveal that long-term karate practice is associated to a significant endocrine modulation, which suggests interesting psychobiological implications, and lends itself to potential clinical considerations. Further research is needed to properly assess the scope of the peculiar hormonal profile displayed by advanced karate practitioners.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tec

Immune modulation after long-term karate practice

Introduction: Karate is a Japanese martial arts system which traces its roots back to China, and is nowadays widely popular both as a method of self-defense, as well as a discipline with potential physical and psychological benefits. However, karate has been scarcely investigated from a psychobiological perspective, and its effects on the immune system remain virtually unknown. Therefore, we designed the present study with the aim of analyzing the effects of several years of regular karate practice on different immune parameters. Methods: 27 healthy volunteer subjects participated in the study, 15 being allocated to the experimental group, and 12 to the control group. Experimental subjects were all karate players who had practiced this martial art for a minimum of three years. Blood samples for the quantification of immune parameters (leukocytes, neutrophils, monocytes, eosinophils, basophils, lymphocytes, IgG, IgA, IgM, IgE) were taken in both groups. As statistical analysis, a t-test for independent groups was performed in each dependent variable. Results: Compared to the control group, karate practitioners exhibited a significantly higher number of leukocytes, monocytes, and lymphocytes, as well as greater serum concentrations of IgG and IgM. Conclusions: Our findings show that long-term karate practice is related to a broad modulation of immune parameters, including leukocytes counts as well as immunoglobulin concentrations. This peculiar immunomodulatory profile, apart from its psychobiological relevance, may have noteworthy clinical implications. Further investigation would be necessary to fully elucidate the influence that long-term karate training can exert on the immune system.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tec

Application of Electrical Bio-Impedance for the Evaluation of Strawberry Ripeness

"This is an Author's Accepted Manuscript of an article published in González-Araiza, José Raymundo, María Coral Ortiz-Sánchez, Francisco Miguel Vargas-Luna, and José Manuel Cabrera-Sixto. 2016. Application of Electrical Bio-Impedance for the Evaluation of Strawberry Ripeness. International Journal of Food Properties 20 (5). Informa UK Limited: 1044 50. doi:10.1080/10942912.2016.1199033, available online at: https://www.tandfonline.com/doi/full/10.1080/10942912.2016.1199033."[EN] Electrical bio-impedance measurements were conducted on local strawberry fruits. A non-destructive device was designed to obtain the impedance spectrum of the whole fruit. Four electrical variables were tested: low frequency resistor R0 (related to extracellular resistances), the high frequency resistor R∞ (related to intracellular resistances), and constant phase element (magnitude and phase, related to the membrane capacitances and heterogeneity, respectively). In parallel with the electrical bio-impedance measurement, color and firmness were correlated to the ripeness stage. The results indicated that the strawberries at the highest stage of ripeness had significantly lower constant phase element and R0 values.The authors would like to express their gratitude to Mr. and Mrs. Abraham from Irapuato, Mexico for providing the fruits, and to Mr. Juan Manuel Noriega from the University of Guanajuato for his technical support. The authors would like to thank the University of Guanajuato for the financial support.Gonzalez-Araiza, J.; Ortiz Sánchez, MC.; Vargas-Luna, F.; Cabrera-Sixto, J. (2017). Application of Electrical Bio-Impedance for the Evaluation of Strawberry Ripeness. International Journal of Food Properties. 20(5):1044-1050. https://doi.org/10.1080/10942912.2016.1199033S10441050205Cordenunsi, B. R., Nascimento, J. R. O., & Lajolo, F. M. (2003). Physico-chemical changes related to quality of five strawberry fruit cultivars during cool-storage. Food Chemistry, 83(2), 167-173. doi:10.1016/s0308-8146(03)00059-1Sacks, E. J., & Shaw, D. V. (1994). Optimum Allocation of Objective Color Measurements for Evaluating Fresh Strawberries. Journal of the American Society for Horticultural Science, 119(2), 330-334. doi:10.21273/jashs.119.2.330Harker, F. R., & Forbes, S. K. (1997). Ripening and development of chilling injury in persimmon fruit: An electrical impedance study. New Zealand Journal of Crop and Horticultural Science, 25(2), 149-157. doi:10.1080/01140671.1997.9514001Bauchot, A. D., Harker, F. R., & Arnold, W. M. (2000). The use of electrical impedance spectroscopy to assess the physiological condition of kiwifruit. Postharvest Biology and Technology, 18(1), 9-18. doi:10.1016/s0925-5214(99)00056-3Harker, F. R., & Maindonald, J. H. (1994). Ripening of Nectarine Fruit (Changes in the Cell Wall, Vacuole, and Membranes Detected Using Electrical Impedance Measurements). Plant Physiology, 106(1), 165-171. doi:10.1104/pp.106.1.165Fang, Q., Liu, X., & Cosic, I. (s. f.). Bioimpedance Study on Four Apple Varieties. 13th International Conference on Electrical Bioimpedance and the 8th Conference on Electrical Impedance Tomography, 114-117. doi:10.1007/978-3-540-73841-1_32Vozáry, E., & Benkó, P. (2010). Non-destructive determination of impedance spectrum of fruit flesh under the skin. Journal of Physics: Conference Series, 224, 012142. doi:10.1088/1742-6596/224/1/012142Harker, F. R., Elgar, H. J., Watkins, C. B., Jackson, P. J., & Hallett, I. C. (2000). Physical and mechanical changes in strawberry fruit after high carbon dioxide treatments. Postharvest Biology and Technology, 19(2), 139-146. doi:10.1016/s0925-5214(00)00090-9Juansah, J., Budiastra, I. W., Dahlan, K., & Seminar, K. B. (2014). Electrical Properties of Garut Citrus Fruits at Low Alternating Current Signal and its Correlation with Physicochemical Properties During Maturation. International Journal of Food Properties, 17(7), 1498-1517. doi:10.1080/10942912.2012.723233O’Toole, M. D., Marsh, L. A., Davidson, J. L., Tan, Y. M., Armitage, D. W., & Peyton, A. J. (2015). Non-contact multi-frequency magnetic induction spectroscopy system for industrial-scale bio-impedance measurement. Measurement Science and Technology, 26(3), 035102. doi:10.1088/0957-0233/26/3/035102Gore, C. M., White, J. O., Wachsman, E. D., & Thangadurai, V. (2014). Effect of composition and microstructure on electrical properties and CO2 stability of donor-doped, proton conducting BaCe1−(x+y)ZrxNbyO3. Journal of Materials Chemistry A, 2(7), 2363. doi:10.1039/c3ta12668

Ballistic Localization in Quasi-1D Waveguides with Rough Surfaces

Structure of eigenstates in a periodic quasi-1D waveguide with a rough surface is studied both analytically and numerically. We have found a large number of "regular" eigenstates for any high energy. They result in a very slow convergence to the classical limit in which the eigenstates are expected to be completely ergodic. As a consequence, localization properties of eigenstates originated from unperturbed transverse channels with low indexes, are strongly localized (delocalized) in the momentum (coordinate) representation. These eigenstates were found to have a quite unexpeted form that manifests a kind of "repulsion" from the rough surface. Our results indicate that standard statistical approaches for ballistic localization in such waveguides seem to be unappropriate.Comment: 5 pages, 4 figure

Extended States in a One-dimensional Generalized Dimer Model

The transmission coefficient for a one dimensional system is given in terms of Chebyshev polynomials using the tight-binding model. This result is applied to a system composed of two impurities located between $N$ sites of a host lattice. It is found that the system has extended states for several values of the energy. Analytical expressions are given for the impurity site energy in terms of the electron's energy. The number of resonant states grows like the number of host sites between the impurities. This property makes the system interesting since it is a simple task to design a configuration with resonant energy very close to the Fermi level $E_F$.Comment: 4 pages, 3 figure

Local and average fields inside surface-disordered waveguides: Resonances in the one-dimensional Anderson localization regime

We investigate the one-dimensional propagation of waves in the Anderson localization regime, for a single-mode, surface disordered waveguide. We make use of both an analytical formulation and rigorous numerical simulation calculations. The occurrence of anomalously large transmission coefficients for given realizations and/or frequencies is studied, revealing huge field intensity concentration inside the disordered waveguide. The analytically predicted s-like dependence of the average intensity, being in good agreement with the numerical results for moderately long systems, fails to explain the intensity distribution observed deep in the localized regime. The average contribution to the field intensity from the resonances that are above a threshold transmission coefficient $T_{c}$ is a broad distribution with a large maximum at/near mid-waveguide, depending universally (for given $T_{c}$) on the ratio of the length of the disorder segment to the localization length, $L/\xi$. The same universality is observed in the spatial distribution of the intensity inside typical (non-resonant with respect to the transmission coefficient) realizations, presenting a s-like shape similar to that of the total average intensity for $T_{c}$ close to 1, which decays faster the lower is $T_{c}$. Evidence is given of the self-averaging nature of the random quantity $\log[I(x)]/x\simeq -1/\xi$. Higher-order moments of the intensity are also shown.Comment: 9 pages, 9 figure

Experimental and theoretical investigations on a CVD grown thin film of polymeric carbon nitride and its structure

A polymeric carbon nitride thin film has been grown using chemical vapor deposition. The characterization of the material shows that it has the same molecular composition as a formerly synthesized graphitic carbon nitride powder but both substances differ widely in their structural organization. In particular, our analyses reveal a paradoxical character in which the thin film sample exhibits simultaneously a high degree of organization in the stacking of the polymer sheets with strong inter-layer interactions, as expected from the growth technique, and a complete lack of crystallinity. A comprehensive theoretical study based on massive semi-empirical quantum chemistry computations has permitted to explain the properties of the material and to elucidate fundamental issues regarding the structural conformation of graphitic carbon nitride