Determining the effect of one decade on fitness of elite Austrian youth soccer players using propensity score matching

Current trends in attacking strategies and increases in external workload have led to a need for fast and well-conditioned athletes in modern soccer. More recently, progressions in speed, coordination, power and endurance were found over a decade in elite Austrian youth players. However, possible confounders such as relative age, maturation, learning effects, and academy philosophy may have influenced these changes. The present study aimed to determine the decade effect on fitness under statistical control of players' exact age, height, body mass, test location as well as total number of pretests and time interval between test and pretest. Players annually completed a battery of anthropometric, general and soccer-specific fitness tests. MANCOVA was calculated to identify the overall impacts of the covariates on fitness. To balance the covariates of initially 2,530 “former” (2002 to 2005) and 2,611 “recent” (2012 to 2015) players, 1:1 nearest neighbor propensity score (PS) matching was used, resulting in 587 U13, 573 U14, 475 U15, 325 U16, 262 U17, and 129 U18 matched pairs. The decade effect on fitness was assessed by independent t-tests and Cohen's d separately at each age group. Superior performances of recent players were found for linear sprint across all age categories (d = 0.154–0.476) as well as for agility (d = 0.125–0.340) and change-of-direction speed (d = 0.172–0.466) in U15 to U18. Reaction speed increased in U13 (d = 0.288) and U15 (d = 0.310). Flexibility reduced over the decade in all age categories (d = −0.151 to −0.589) and upper-limb power decreased (d = −0.278 to −0.347) in U13 and U14. Balancing the covariate distribution via PS matching generally confirmed previous findings, with fitness decade effects reflecting the athletic needs for modern soccer. Since fitness performance changed over time, reference values should be periodically updated. Coaches favor both physical and cognitive fast players nowadays. Thus, training should target all aspects of speed, without disregarding flexibility, upper-limb power and other preventive strategies that keep the players on the pitch

Engineering of carbohydrate oxidoreductases for sensors and bio-fuelcells

Pyranose dehydrogenase (PDH) and pyranose 2-oxidase (POx) are flavoproteins that catalyze the oxidation of free, non-phosphorylated sugars to the corresponding ketosugars. Pyranose dehydrogenase has a broad substrate specificity for monosaccharides (and few disaccharides), but is limited to a narrow range of electron acceptors and reacts extremely slowly with dioxygen, whereas pyranose 2-oxidase shows pronounced specificity for glucose and displays high oxidase as well as dehydrogenase activity. For bio-fuelcell and sensor applications, oxygen reactivity is undesirable as it leads to electron leakage and the formation of damaging hydrogen peroxide; for biocatalytic applications, oxygen reactivity is advantageous, as oxygen is freely available and obviates downstream removal of undesired electron acceptors. Site-saturation mutagenesis libraries of eleven (POx) and twelve (PDH) residues around the active sites were screened for oxidase and dehydrogenase activities. In POx, variants T166R, Q448H, L545C, L547R and N593C displayed reduced oxidase activities (between 40% and 0.2% of the wildtype) concomitant with unaffected or even increased dehydrogenase activity, dependent on the electron acceptor used (DCPIP, 1,4-benzoquinone or ferricenium ion). Kinetic characterization showed that both affinity and turnover numbers can be affected. The switch from oxidase to dehydrogenase activity was also observed electrochemically using screen-printed electrodes. In this miniaturized set-up with a reaction volume of only 50 µL the dehydrogenase activity of variant N593C was entirely preserved in the presence of a suitable mediator, shuttling electrons from the FAD cofactor to the electrode surface. The oxidase activity, utilizing molecular oxygen as acceptor, is abolished in this variant. Of all variants of PDH that were produced by saturation mutagenesis, only variants of one position displayed increased oxygen reactivity to a minor degree. Histidine 103, carrying the covalently attached FAD cofactor, was substituted by tyrosine, phenylalanine, tryptophan and methionine. Variant H103Y displayed a five-fold increase of oxygen reactivity. Stopped flow analysis revealed that the mutation slowed down the reductive half-reaction whereas the oxidative half-reaction was affected to a minor degree. No alterations in the secondary structure were observed, but disruption of the FAD bond had negative effects on thermal and conformational stability. We also engineered PDH by systematically removing several N-glycosylation sites, in order to improve performance by reducing the distance of the active site to the electrode surface, improving accessibility for redox polymers and facilitate denser enzyme packing on the electrode. One glycosylation site, N319, was found to be indispensable for functional expression and folding of the enzyme, as no active variants could be obtained. A variant with two sites, N75 and N175 near the active site entrance, exchanged against G and Q, respectively, showed significantly improved properties when used on electrodes with Osmium-based redox polymers (Mediated Electron Transfer) and a low level of Direct Electron Transfer. The lack of two glycosylation sites results in minor negative effects on expression yield and stability. Removal of a third site, N252, on the opposite side of the active site entrance, does not bring further improvements in catalysis and electron transfer, but is detrimental to functional expression and stability. The bulk of hyperglycosylation of the recombinantly expressed enzyme (observed in both Pichia pastoris and Saccharomyces cerevisiae) is located only on this one glycosylation site. Please click Additional Files below to see the full abstract

Retrospective analysis of anthropometric and fitness characteristics associated with long-term career progression in Rugby League.

The current study retrospectively investigated the differences in anthropometric and fitness characteristics of junior rugby league players selected onto a talent identification and development (TID) programme between long-term career progression levels (i.e., amateur, academy, professional)

Changes Over a Decade in Anthropometry and Fitness of Elite Austrian Youth Soccer Players

Increases in physical (e.g., high-intensity running and sprinting), technical (e.g., passing rate), and tactical (e.g., player density) aspects made elite level soccer more challenging within the past years. The aim of the study was to evaluate whether these evolutions are also been reflected in changes in anthropometric and fitness characteristics between former (2002 to 2005) and current (2012 to 2015) elite Austrian youth development center (U13 to U14) and soccer academy (U15 to U18) players. A battery of anthropometric, general and soccer-specific fitness tests was conducted annually at the end of each year. Independent t-test and Cohen’s d (ES) were calculated to compare the two four-year periods (2530 vs. 2611 players) at each age group separately. Current players were significantly faster in 20 m sprint (ES = 0.26–0.50) and reaction test (ES = 0.15–0.39, except for U18), but less flexible at sit-and-reach (ES = –0.19 to –0.55), in all age categories. Whereas height (ES = 0.26–0.32), body mass (ES = 0.11–0.18) and countermovement jump (ES = 0.24–0.26) increased significantly at youth development center level, current academy players performed superior at shuttle sprint (ES = 0.21–0.59), hurdles agility run (ES = 0.24–0.49), and endurance run (ES = 0.11–0.20). These changes over time in speed, change-of-direction ability, lower-body power, coordination, and endurance were attributed to modern training approaches (e.g., modified games and change-of-direction drills) and modifications in selection politics (e.g., coaches favor speed and decision-making skills)

Mercury pollution for marine environment at Farwa Island, Libya

Coimmobilization of pyranose dehydrogenase as an enzyme catalyst, osmium redox polymers [Os­(4,4′-dimethoxy-2,2′-bipyridine)₂(poly­(vinylimidazole))₁₀Cl]⁺ or [Os­(4,4′-dimethyl-2,2′-bipyridine)₂(poly­(vinylimidazole))₁₀Cl]⁺ as mediators, and carbon nanotube conductive scaffolds in films on graphite electrodes provides enzyme electrodes for glucose oxidation. The recombinant enzyme and a deglycosylated form, both expressed in Pichia pastoris, are investigated and compared as biocatalysts for glucose oxidation using flow injection amperometry and voltammetry. In the presence of 5 mM glucose in phosphate-buffered saline (PBS) (50 mM phosphate buffer solution, pH 7.4, with 150 mM NaCl), higher glucose oxidation current densities, 0.41 mA cm^–2, are obtained from enzyme electrodes containing the deglycosylated form of the enzyme. The optimized glucose-oxidizing anode, prepared using deglycosylated enzyme coimmobilized with [Os­(4,4′-dimethyl-2,2′-bipyridine)₂(poly­(vinylimidazole))₁₀Cl]⁺ and carbon nanotubes, was coupled with an oxygen-reducing bilirubin oxidase on gold nanoparticle dispersed on gold electrode as a biocathode to provide a membraneless fully enzymatic fuel cell. A maximum power density of 275 μW cm^–2 is obtained in 5 mM glucose in PBS, the highest to date under these conditions, providing sufficient power to enable wireless transmission of a signal to a data logger. When tested in whole human blood and unstimulated human saliva maximum power densities of 73 and 6 μW cm^–2 are obtained for the same fuel cell configuration, respectively

Physical characteristics and the talent identification and development processes in male youth soccer: A narrative review

Talent identification and development in male youth soccer are complex and multidimensional processes. The English Football Association “4 Corner Model” is often adopted by academies to support coaches and practitioners to implement a multidisciplinary approach to their talent identification and development framework. This holistic approach is characterized by technical/tactical, psychological, social, and physical attributes, which are central to academy recruitment and individual long-term athlete development. The aim of this narrative review is to provide a critical synthesis of the physical characteristics within this model, which facilitate talent identification and development, namely physical performance, growth and maturation, and the relative age effect

Rational engineering of Pyranose Dehydrogenase for application to enzymatic bio-fuel cells

Enzymatic bio-fuel cells transform chemical into electrical energy, with the help of enzyme modified electrodes. Due their membraneless design, they have been suggested for powering transportable micro devices and implantable sensors. One of the major remaining challenges is the achievable maximum power output of these systems. Here, rational enzyme engineering of an oxidoreductase for anode modification, pyranose dehydrogenase, was employed to increase achievable maximum current densities. The fungal enzyme pyranose dehydrogenase is of interest due to its broad substrate specificity, capability of dioxidation, and inability of reducing O2 to H2O2. Pyranose dehydrogenase from Agaricus bisporus was heterologously expressed in this work and compared to the three other reported recombinant pyranose dehydrogenases, to select the most promising target for enzyme engineering. Agaricus meleagris pyranose dehydrogenase I was chosen due to its generally moderately better catalytic efficiency and enzyme stability. The rational engineering strategy was based on reducing N-glycosylation, which was previously shown to be disadvantageous for bio-fuel cell performance. A systematic set of partially N-glycosylated Agaricus meleagris pyranose dehydrogenase I variants was tested on Os-polymer modified graphite electrodes. Knocking out the only apparently overglycosylated site, N252, did not create a variant with improved performance on Os-polymer modified electrodes. The site N319, on the other side, could not be knocked out without preventing functional recombinant expression in Pichia pastoris. However, electrodes based on the variant N75G/N175Q yielded an approximately 10-fold increased maximum current density (290 A cm-2) compared to the equivalent electrodes with recombinant wild type enzyme. It is therefore a promising candidate for application to future enzymatic bio-fuel cell anodes.Enzymatische Biobrennstoffzellen wandeln chemische in elektrische Energie mithilfe Enzym modifizierter Elektroden um. Aufgrund deren membranloser Designs wurden sie für die Energieversorgung von Miniaturgeräten und implantierbaren Sensoren vorgeschlagen. Eine verbleibende Herausforderung ist die erreichbare maximale elektrische Leistung dieser Systeme. Proteindesign wurde in diesem Werk an einer vielversprechenden Oxidoreduktase, Pyranose Dehydrogenase, angewandt, um eine Erhöhung der maximalen Stromdichte zu erreichen. Dieses Enzym ist von Interesse wegen seiner breiten Substratspezifität, der Fähigkeit zur Dioxidation und da es die Reduktion von O2 zu H2O2 nicht katalysiert. Pyranose Dehydrogenase von Agaricus bisporus wurde in dieser Arbeit rekombinant exprimiert und mit den anderen 3 publizierten rekombinanten Varianten verglichen um die vielversprechendste Basis für rationales Proteindesign zu identifizieren. Agaricus meleagris Pyranose Dehydrogenase I wurde dafür, aufgrund höherer katalytischer Effizienz und Enzymstabilität, schlussendlich ausgewählt. Die Proteindesignstrategie basierte auf der Reduzierung der für Biobrennstoffzellen nachteiligen N-Glykosylierung. Ein systematisches Set an partiell N-glykosylierter Agaricus meleagris Pyranose Dehydrogenase I Varianten wurde auf Os-Polymer modifizierten Graphitelektroden getestet. Die Eliminierung der einzigen überglykosylierten Stelle, N252, führte nicht zu höheren Stromdichten der enzymatischen Bioelektroden. Die Stelle N319 wiederum konnte nicht eliminiert werden, ohne die funktionelle rekombinante Produktion des Enzyms in Pichia pastoris zu unterbinden. Elektroden basierend auf der Variante N75G/N175Q hingegen zeigten eine ca. 10-fache Steigerung der maximalen Stromdichte (290 A cm-2) im Vergleich zu äquivalenten Elektroden mit dem rekombinanten wildtyp Enzym. Diese Variante ist somit ein vielversprechender Kandidat für Anwendung in enzymatischen Biobrennstoffzellenanoden.Christoph GonausZusammenfassung in deutscher SpracheUniversität für Bodenkultur Wien, Dissertation, 2016OeBB(VLID)193144

Entwässerung von Flachdächern und Dachterrassen : Möglichkeiten der Optimierung der Freispiegelentwässerung

Inhalt dieser Arbeit sind die Möglichkeiten der Optimierung von Freispiegelentwässerungen. Um diese Frage zu beantworten werden zuerst die generellen Unterschiede der Anforderungen bei unterschiedlichen Dachaufbauten erläutert. Ebenfalls werden die allgemeinen Bestandteile von Entwässerungssystemen beschrieben und analysiert. In einem Vergleich der Druck- mit der Freispiegelentwässerung erfolgt die Aufarbeitung der Vor- und Nachteile beider Systeme. Eine ausführliche Analyse der normgerechten Dimensionierung, Planung und Konstruktion, unter Berücksichtigung der ÖNORMEN B 2501, EN 12056-3 und der im Februar 2019 aktualisierten B 3691, der Dachentwässerung ist ebenso Bestandteil wie die praktische Anwendung dieser am Beispiel des Projektes „LeoS“. Die Herstellung der Abdichtung ist dabei ebenso berücksichtigt wie die Verlegung des Leitungssystems oder auch die nötigen Anschlüsse von diversen Bauteilen. Durch die Gegenüberstellung der durchgeführten Dimensionierung mit dem geplanten bzw. ausgeführten System kommt es zu einem Ergebnis, welches rechnerisches Verbesserungspotential liefert. Dieses sollte aber auf Grund praktischer und konstruktiver Nachteile in der Ausführung und Wartung nur bedingt ausgeschöpft werden. In der Planung ist hier somit immer ein Kompromiss zwischen theoretisch bestmöglich und praktisch bestausführbar zu finden.Contents of this work are the possibilities of the optimization of freestanding drainage systems. To answer this question, the general differences in the requirements for different roof structures are first described. Also, the general components of drainage systems are described and analyzed. In a comparison of pressure and gravity drainage, the advantages and disadvantages of both systems are addressed. A detailed analysis of the standard-compliant dimensioning, planning and construction, taking into account the ÖNORMEN B 2501, EN 12056-3 and the, in February 2019, updated B 3691, of the roof drainage is just as much a part of this as the practical use in the example of the project "LeoS". The manufacture of the seal is taken into account as well as the laying of the pipe system or the necessary connections of various components. By comparing the dimensioning carried out with the planned or executed system, there is a result which provides computational potential for improvement. However, this should be exploited due to practical and constructive disadvantages in the design and maintenance only partially. In the planning, there is always a compromise between theoretically best possible and practically best execution feasible

'Celebrate the magic of winter sports' : die bewerbung von Salzburg um die Olympischen Winterspiele 2014

Analyse des causes et conséquences de l'échec de la candidature de la ville autrichienne de Salzburg à l'organisation des Jeux Olympiques d'hiver 2014 (qui auront lieu à Sotchi) : manque de soutien financier et désintérêt fédéral, aspects politiques et structurels. Interdépendances entre la politique, l'économie et le sport, divergences entre revendications régionales et intérêts nationaux. Aspects positifs d'un échec : engagement des entreprises, retombées publicitaires pour la régio

Maturity Status Strongly Influences the Relative Age Effect in International Elite Under-9 Soccer

The aim of the study was to assess the role of the relative age effect (RAE) and to investigate the influence of the biological maturity status on the RAE in international under-9 soccer. The birth dates of 222 male participants of the U9 Eurochampionship Soccer Tournament in Vienna in 2016 were analyzed and divided into four relative age quarters (Q1-Q4) and the biological maturity status was assessed with the age at peak height velocity (APHV) method. Based on the mean±standard deviation of the APHV, the athletes were divided into three groups of maturity: early, normal and late maturing. Chi-Square-tests were used to assess the difference between the observed and the expected even relative age quarter distribution and to evaluate the difference between the observed distribution of early, normal and late maturing athletes and the expected normal distribution. A univariate analysis of variance was performed to assess differences in the APHV between the relative age quarters. A RAE was present (χ2 = 23.87; p < 0.001; ω = 0.33). A significant difference was found in APHV between the four relative age quarters (F = 9.906; p < 0.001); relatively older athletes were significantly less mature. A significant difference was found between the distribution of early, normal and late maturing athletes and the expected normal distribution for athletes of Q1 (high percentage of late maturing athletes: 27%; χ2 = 17.69; p < 0.001; ω = 0.46) and of Q4 (high percentage of early maturing soccer players: 31%; χ2 = 12.08; p = 0.002; ω = 0.58). These findings demonstrated that the selection process in international soccer, with athletes younger than 9 years, seems to be associated with the biological maturity status and the relative age. Relatively younger soccer players seem to have a better chance for selection for international tournaments, if they enter puberty at an earlier age, whereas relatively older athletes seem to have an increased likelihood for selection independent of their biological maturity status