Η επίδραση της ισορροπίας στις τεχνικές δεξιότητες νεαρών ποδοσφαιριστών

Το ποδόσφαιρο είναι ένα πολυσύνθετο άθλημα όπου η καλή απόδοση εξαρτάται από την αλληλεπίδραση διαφορετικών χαρακτηριστικών όπως φυσιολογικών, τακτικών, ψυχολογικών και τεχνικών. Το στοιχείο της τεχνικής ικανότητας αποτελεί ίσως το σημαντικότερο παράγοντα στη διάκριση των ποδοσφαιριστών και στον καθορισμό του επιπέδου τους. Επιπλέον, η διαρκώς αυξανόμενη ταχύτητα του παιχνιδιού σε συνδυασμό με τον περιορισμό του πεδίου δράσης των αθλητών όπως προκύπτει από την ανάπτυξη της σύγχρονης τακτικής επιτάσσει τη δημιουργία αρτιότερων τεχνικά ποδοσφαιριστών. Mια από τις πιο βασικές ικανότητες νευρομυϊκής συναρμογής είναι η ισορροπία (Riccoti et al., 2011). Στο ποδόσφαιρο η εκτέλεση πολλών τεχνικών δεξιοτήτων όπως είναι η μεταβίβαση, το σουτ, ο ελιγμός με μπάλα και το σταμάτημα της μπάλας πραγματοποιούνται ενώ ο ποδοσφαιριστής στηρίζεται στο ένα πόδι. Η ισορροπία επομένως παίζει σημαντικό ρόλο στις συνεχείς αλλαγές κατεύθυνσης που πραγματοποιούνται κατά τη διάρκεια του αγώνα καθώς και στις καταστάσεις εκείνες του παιχνιδιού όπου απαιτείται σωματική επαφή με τον αντίπαλο ή σε συνθήκες ολισθηρού και κακού αγωνιστικού χώρου (Bekris et al, 2012). Το γεγονός ότι οι άνθρωποι ως δίποδα μετακινούνται με το ένα πόδι να στηρίζεται στο έδαφος (περπάτημα), χωρίς κανένα πόδι να στηρίζεται στο έδαφος (τρέξιμο) ή στεκόμαστε με τα δυο πόδια σε αυτό (στάση) δημιουργεί μια σημαντική πρόκληση στο σύστημα ελέγχου της ισορροπίας (Winter, 1995). Σκοπός της παρούσας εργασίας ήταν να εξετάσει την επίδραση της ισορροπίας στις τεχνικές δεξιότητες νεαρών ποδοσφαιριστών. Για την πραγματοποίηση της παρούσας έρευνας έλαβαν μέρος 20 νεαροί ποδοσφαιριστές ηλικίας 12-13 ετών, οι οποίοι αγωνίζονται στην ίδια ποδοσφαιρική ομάδα Α΄ ερασιτεχνικής κατηγορίας της Αθήνας. Στη συγκεκριμένη έρευνα η ισορροπία συσχετίστηκε θετικά μόνο με τη δεξιότητα της πάσας. Αυτό κρίνεται απόλυτα φυσιολογικό λόγω του ότι κατά την διαδικασία της πάσας ο αθλητής στηρίζεται στο ένα πόδι. Προτείνεται να εξεταστεί η επίδραση μιας εξειδικευμένης προπόνησης ισορροπίας στην βελτίωση της και κατ επέκταση στην βελτίωση των τεχνικών ικανοτήτων. Ακόμα προτείνεται η εξερεύνηση της επίδρασης της ισορροπίας και σε άλλες ηλικιακές ομάδες.Football is a complex sport where good performance depends on the interaction of different characteristics such as physiological, tactical, psychological and technical. The element of technical capability is perhaps the most important factor to distinguish the players and determine their level. Moreover, the increasing speed of the game in conjunction with limiting the scope of the athletes as evidenced by the development of modern tactics requires the creation of more informed technical players. One of the most basic skills neuromuscular assembly is balance (Riccoti et al., 2011). In football the performance of many technical skills such as the transfer of the shot, the maneuver to pass the ball stopping place while the player rests on one leg. The balance therefore plays an important role in the continuous direction changes carried out during the race and in those situations where the game requires physical contact with the opponent or in slippery conditions, and bad pitch (Bekris et al, 2012). The fact that people as bipeds moving with one foot resting on the ground (walking), no foot rests on the ground (running) or stand with both feet on it (stop) creates a significant challenge to the balance control system (Winter, 1995). The purpose of this study was to examine the effect of the balance on the technical skills of young players. For the realization of this research took part 20 young players aged 12-13 years, who are fighting on the same football team A recreational class of Athens. In this research, the balance was associated positively with the skill of setting. This is perfectly normal because during the process of the pass the athlete relies on one leg. It is proposed to examine the effect of a specific balance training to improve and therefore to the improvement of technical skills. Even proposed to explore the effect of balance and other age groups

Chemical Composition and Evaluation of the Biological Properties of the Essential Oil of the Dietary Phytochemical Lippia citriodora

The aim of the study was to characterize the chemical composition and biological properties of the essential oil from the plant Lippia citriodora grown in Greece. The essential oil volatiles were analyzed by gas chromatography–mass spectrometry GC-MS indicating citral as the major component. Τhe antimicrobial properties were assayed using the disk diffusion method and the minimum inhibitory and non-inhibitory concentration values were determined. Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus, Saccharomyces cerevisiae, and Aspergillus niger were sensitive to Lippia citriodora oil, but not Escherichia coli, Salmonella Enteritidis, Salmonella typhimurium, and Pseudomonas fragi. Adversely, all microbes tested were sensitive to citral. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays were used to assess direct antioxidant activity, which proved to be weak for both agents, while comet assay was utilized to study the cytoprotective effects against H2O2-induced oxidative damage in Jurkat cells. Interestingly, the oil showed a more profound cytoprotective effect compared to citral. The antiproliferative activity was evaluated in a panel of cancer cell lines using the sulforhodamine B (SRB) and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-S-(phenylamino) carbonyl-2-tetrazolium hydroxide (XTT) assays and both agents demonstrated potent antiproliferative activity with citral being more cytotoxic than the oil. Taken together, the essential oil of Lippia citriodora and its major component, citral, exert diverse biological properties worthy of further investigation

Managing Distributed Flexibility under Uncertainty by Combining Deep Learning with Duality

In modern power systems, small distributed energy resources (DERs) are considered a valuable source of flexibility towards accommodating high penetration of Renewable Energy Sources (RES). In this paper we consider an economic dispatch problem for a community of DERs, where energy management decisions are made online and under uncertainty. We model multiple sources of uncertainty such as RES, wholesale electricity prices as well as the arrival times and energy needs of a set of Electric Vehicles. The economic dispatch problem is formulated as a multi-agent Markov Decision Process. The difficulties lie in the curse of dimensionality and in guaranteeing the satisfaction of constraints under uncertainty. A novel method, that combines duality theory and deep learning, is proposed to tackle these challenges. In particular, a Neural Network (NN) is trained to return the optimal dual variables of the economic dispatch problem. By training the NN on the dual problem instead of the primal, the number of output neurons is dramatically reduced, which enhances the performance and reliability of the NN. Finally, by treating the resulting dual variables as prices, each distributed agent can self-schedule, which guarantees the satisfaction of its constraints. As a result, our simulations show that the proposed scheme performs reliably and efficiently

ARMONIA: A Unified Access and Metro Network Architecture

We present a self-configured and unified access and metro network architecture, named ARMONIA. The ARMONIA network monitors its status, and dynamically (re-)optimizes its configuration. ARMONIA leverages software defined networking (SDN) and network functions virtualization (NFV) technologies. These technologies enable the access and metro convergence and the joint and efficient control of the optical and the IP equipment used in these different network segments. Network monitoring information is collected and analyzed utilizing machine learning and big data analytics methods. Dynamic algorithms then decide how to adapt and dynamically optimize the unified network. The ARMONIA network enables unprecedented resource efficiency and provides advanced virtualization services, reducing the capital expenditures (CAPEX) and operating expenses (OPEX) and lowering the barriers for the introduction of new services. We demonstrate the benefits of the ARMONIA network in the context of dynamic resource provisioning of network slices. We observe significant spectrum and equipment savings when compared to static overprovisioning

Phytochemical profile and evaluation of the biological activities of essential oils derived from the greek aromatic plant species Ocimum basilicum, Mentha spicata, Pimpinella anisum and Fortunella margarita

Natural products, known for their medicinal properties since antiquity, are continuously being studied for their biological properties. In the present study, we analyzed the composition of the volatile preparations of essential oils of the Greek plants Ocimum basilicum (sweet basil), Mentha spicata (spearmint), Pimpinella anisum (anise) and Fortunella margarita (kumquat). GC/MS analyses revealed that the major components in the essential oil fractions, were carvone (85.4%) in spearmint, methyl chavicol (74.9%) in sweet basil, trans-anethole (88.1%) in anise, and limonene (93.8%) in kumquat. We further explored their biological potential by studying their antimicrobial, antioxidant and antiproliferative activities. Only the essential oils from spearmint and sweet basil demonstrated cytotoxicity against common foodborne bacteria, while all preparations were active against the fungi Saccharomyces cerevisiae and Aspergillus niger. Antioxidant evaluation by DPPH and ABTS radical scavenging activity assays revealed a variable degree of antioxidant potency. Finally, their antiproliferative potential was tested against a panel of human cancer cell lines and evaluated by using the sulforhodamine B (SRB) assay. All essential oil preparations exhibited a variable degree of antiproliferative activity, depending on the cancer model used, with the most potent one being sweet basil against an in vitro model of human colon carcinoma

The mental health care system for children and adolescents in Greece: a scoping review and structure assessment

The mental health system in Greece faces challenges to complete its transition to a community-oriented model, with particular concerns for child and adolescent mental care due to lower coverage and service gaps. The aim of this study is to perform a scoping review of the mental health care system providing care to children and adolescents operating in the country. We initially review the National Health Care Service (ESY), encompassing its governance, participating agents, financing, coverage, organizational structure, and the range of services offered. Then, we review the mental health care system embedded within ESY, tracing its historical development from the psychiatric reform to its current state. We outline the system’s structure, organization, available services, human resources, and coverage, with specific focus on child and adolescent care; psychoeducational facilities within the school system are also reviewed. For a situational analysis of service availability and distribution, we mapped facilities providing mental health care to children and adolescents, uncovering underserved regions. Our assessment reveals an established framework for a community-oriented, universal access, mental health system, yet facing several barriers to its full realization, including an inconsistent primary healthcare system, a shortage of specialists in the public sector, imbalanced distribution of services, lack of coordination of care across providers, substantial underfunding and absence of quality monitoring. To address these challenges, we explore potential interventions that have proven effective in analogous scenarios, encompassing strategies to promote child and adolescent mental health in primary care, coordinate patient pathways, establish standards of care, and monitor performance