Publications by authors named "Maria Zakynthinaki"

Hallux Valgus foot deformity affects gait performance. Common treatment options include distal oblique metatarsal osteotomy and chevron osteotomy. Nonetheless, the current process of selecting the appropriate osteotomy method poses potential biases and risks, due to its reliance on subjective human judgment and interpretation.

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In this study, we proposed novel metrics for evaluating volleyball technical performance in relation to the action context. To assess each player's relative participation, we also introduced relative contextual coefficients. We analyzed 20 games played by the world's top eight teams during the 2019 FIVB Women's Club World Championship, using Data Volley software and Python programming.

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Recently, there has been much controversy over the International Association of Athletics Federation (IAAF) regulations regarding eligibility to compete and natural testosterone levels in female athletes. Much interest lies in the analysis of Caster Semenya's extraordinary performance. The objective of this work were, a) Complete an analysis of Caster Semenya's results during the 800m finals and b) search for existing similar performances by other female athletes.

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The ability to stabilize the gun, a crucial factor for performance in air pistol Olympic shooting, is thought to be strongly related to the muscular work of the shooter´s shoulder and forearm. The objective of the present study was to confirm this relationship by analysing the influence of maximal finger flexor forces and maximal isometric shoulder force on performance in female air pistol shooting. Twenty-three female pistol shooters participated in the study.

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The purpose of this study was to examine whether the difference in elite-standard track and field performance between women athletes with and without hyperandrogenism reaches the 10-12% difference in performance between men and women, using only results from elite-standard track and field final competitions. Officially available data from two hyperandrogenic women (Caster Semenya and Dutee Chand) were compared with the characteristic performance of 200m and 800m elite-standard finals. The finishing times of Caster Semenya, before her ineligibility to compete in 2009 and after the suspension of the 2011 IAAF Hyperandrogenism Regulations were found to be respectively 1.

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The purpose of this study was to assess the veracity of the Court of Arbitration for Sport's assertion that sex-differences in athletic performance in elite-standard track and field competition is of the order of 10-12%. Exponential curves were fitted to the data of selected track and field events of the finals of all IAAF World Championships and Olympic Games from 1983 to 2016. For each curve, the coefficient of determination R was calculated, in combination the corresponding 95% confidence intervals for the curve constants.

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The present study implements a stochastic optimization technique to optimally manage freshwater pumping from coastal aquifers. Our simulations utilize the well-known sharp interface model for saltwater intrusion in coastal aquifers together with its known analytical solution. The objective is to maximize the total volume of freshwater pumped by the wells from the aquifer while, at the same time, protecting the aquifer from saltwater intrusion.

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The ability to stabilize the gun is crucial for performance in Olympic pistol shooting and is thought to be related to the shooters muscular strength. The present study examines the relation between performance and finger flexor force as well as shoulder abduction isometric force in senior male air pistol shooting. 46 Spanish national level shooters served as test subjects of the study.

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The objective of the present study was to formulate a simple and at the same time effective mathematical model of heart rate kinetics in response to movement (exercise). Based on an existing model, a system of two coupled differential equations which give the rate of change of heart rate and the rate of change of exercise intensity is used. The modifications introduced to the existing model are justified and discussed in detail, while models of blood lactate accumulation in respect to time and exercise intensity are also presented.

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We present and validate a test able to provide reliable body sway measurements in air pistol shooting, without the use of a gun. 46 senior male pistol shooters who participated in Spanish air pistol championships participated in the study. Body sway data of two static bipodal balance tests have been compared: during the first test, shooting was simulated by use of a dumbbell, while during the second test the shooters own pistol was used.

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Objective: We have studied the effect of moderate physical activity that is performed by healthy women during their entire pregnancy on their perception of health status.

Study Design: Eighty sedentary women were assigned randomly to either an exercise group (n = 40) or a control group (n = 40). Maternal perception of health status and several pregnancy outcomes were recorded.

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We present a method of modeling the basin of attraction as a three-dimensional function describing a two-dimensional manifold on which the dynamics of the system evolves from experimental time series data. Our method is based on the density of the data set and uses numerical optimization and data modeling tools. We also show how to obtain analytic curves that describe both the contours and the boundary of the basin.

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Objective: We examined the effect of light-intensity resistance exercise training that is performed during the second and third trimester of pregnancy by previously sedentary and healthy women on the type of delivery and on the dilation, expulsion, and childbirth time.

Study Design: We randomly assigned 160 sedentary women to either a training (n=80) or a control (n=80) group. We recorded several maternal and newborn characteristics, the type of delivery (normal, instrumental, or cesarean), and dilation, expulsion, and childbirth time.

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This paper applies geometric methods developed to understand chaos and transport in Hamiltonian systems to the study of power distribution in nonlinear waveguide arrays. The specific case of two linearly coupled chi((2)) waveguides is modeled and analyzed in terms of transport and geometry in the phase space. This gives us a transport problem in the phase space resulting from the coupling of the two Hamiltonian systems for each waveguide.

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