105 research outputs found

    Joseph Baker & Nick Wattie – new insights into the concept of innate talent in sport

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    In this target article, Joseph Baker and Nick Wattie revisited the review article on the evidence for innate talent published by Howe, Davidson and Sloboda 20 years ago, and focused mainly on whether this concept was reasonable and scientifically sound, and whether the concept of innate talent was valid also in the world of sport. The main article (CISS_3:006) is then discussed by five peer commentaries (CISS_4:102 – CISS_4:106), written by research experts in this field. Finally, Joseph Baker and Nick Wattie provided a closing response (CISS_4:108) acknowledging critiques, suggestions, and extensions brought forward by the commentators

    Effects of synchronous, auditory stimuli on running performance and heart rate

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    Research has demonstrated that the human being tends to couple body movements and external, acoustic stimuli (metronome or music). This effect is called auditory-motor synchronization. Motivational music possesses qualities which distract from feelings like fatigue and exertion. Combining these two effects may enhance the sports performance even more. Investigations showed that runners can increase their original cadence up to 2%. The purpose of this study was to examine the effects of accelerated, synchronized stimuli on the running performance. Therefore, 28 students (15 ♀, 13 ♂) of the Institute of Sports Science in Innsbruck were asked to do two cooper tests each. After run 1 (no auditory signal), the sample was divided into two groups. In run 2, which took place on a different day, one group listened to music while running; the other group was stimulated by the sound of a metronome. Distance (m) and average heartrate were measured. 75% of the athletes achieved a greater distance under the influence of an acoustic stimulus. In fact, the running distance changed significantly using an acoustic stimulus: +61 m (SD ± 100) or 2.1% (SD ± 3.6). In group 1 (music), the performance improved up to + 3.8% (SD ± 3.3). This difference was significant compared to group 2 (metronome). The average heart rate decreased by 1.5 beats (SD ± 5) from run 1 to run 2. Influenced by music, the average heart rate measured 179 beats (SD ± 8) in contrast to 182 beats (SD ± 10) in run 1 (no acoustic stimulus). If the tempo of the acoustic stimulus is adapted to the accelerated cadence of an athlete (maximum 2%), improved distances due to the synchronization effect can be achieved. In combination with the motivating qualities of music, improved effects in sport performances could be produced

    Biological Maturity Status, Anthropometric Percentiles, and Core Flexion to Extension Strength Ratio as Possible Traumatic and Overuse Injury Risk Factors in Youth Alpine Ski Racers: A Four-Year Prospective Study

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    The aim of the present study was to investigate prospectively the role of biological maturity status, anthropometric percentiles, and core flexion to extension strength ratios in the context of traumatic and overuse injury risk identification in youth ski racing. In this study, 72 elite youth ski racers (45 males, 27 females) were prospectively observed from the age of 10 to 14 years. Anthropometric parameters, biological maturity status, and core flexion to extension strength ratios were assessed twice per year. Type and severity of traumatic and overuse injuries were prospectively recorded during the 4 years. Generalized estimating equations were used to model the binary outcome (0: no injury; 1: ≥1 injury). Factors tested on association with injury risk were sex, relative age quarter, age, maturity group, puberty status, core flexion to extension strength ratio, height percentile group, and weight percentile group. In total, 104 traumatic injuries and 39 overuse injuries were recorded. Age (odds ratio (OR) = 3.36) and weight percentile group (OR = 0.38) were significant risk factors for traumatic injuries (tendency: pubertal status). No significant risk factor for overuse injuries was identified (tendency: maturity group, puberty status, height percentile group). Future studies should focus on identifying risk factors for overuse injuries; growth rates might be of importance

    Comparative analysis of somitogenesis related genes of the hairy/Enhancer of split class in Fugu and zebrafish

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    BACKGROUND: Members of a class of bHLH transcription factors, namely the hairy (h), Enhancer of split (E(spl)) and hairy-related with YRPW motif (hey) (h/E(spl)/hey) genes are involved in vertebrate somitogenesis and some of them show cycling expression. By sequence comparison, identified orthologues of cycling somitogenesis genes from higher vertebrates do not show an appropriate expression pattern in zebrafish. The zebrafish genomic sequence is not available yet but the genome of Fugu rubripes was recently published. To allow comparative analysis, the currently known Her proteins from zebrafish were used to screen the genomic sequence database of Fugu rubripes. RESULTS: 20 h/E(spl)/hey-related genes were identified in Fugu, which is twice the number of corresponding zebrafish genes known so far. A novel class of c-Hairy proteins was identified in the genomes of Fugu and Tetraodon. A screen of the human genome database with the Fugu proteins yielded 10 h/E(spl)/hey-related genes. By analysing the upstream sequences of the c-hairy class genes in zebrafish, Fugu and Tetraodon highly similar sequence stretches were identified that harbour Suppressor of hairless paired binding sites (SPS). This motif was also discovered in the upstream sequences of the her1 gene in the examined fish species. Here, the Su(h) sites are separated by longer intervening sequences. CONCLUSIONS: Our study indicates that not all her homologues in zebrafish have been isolated. Comparison to the human genome suggests a selective duplication of h/E(spl) genes in pufferfish or loss of members of these genes during evolution to the human lineage

    Commissioning of the vacuum system of the KATRIN Main Spectrometer

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    The KATRIN experiment will probe the neutrino mass by measuring the beta-electron energy spectrum near the endpoint of tritium beta-decay. An integral energy analysis will be performed by an electro-static spectrometer (Main Spectrometer), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m^3, and a complex inner electrode system with about 120000 individual parts. The strong magnetic field that guides the beta-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. A system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300{\deg}C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10^{-11} mbar range. It is demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016

    Modelling the impact of toxic and disturbance stress on white-tailed eagle (Haliaeetus albicilla) populations

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    Several studies have related breeding success and survival of sea eagles to toxic or non-toxic stress separately. In the present investigation, we analysed single and combined impacts of both toxic and disturbance stress on populations of white-tailed eagle (Haliaeetus albicilla), using an analytical single-species model. Chemical and eco(toxico)logical data reported from laboratory and field studies were used to parameterise and validate the model. The model was applied to assess the impact of ∑PCB, DDE and disturbance stress on the white-tailed eagle population in The Netherlands. Disturbance stress was incorporated through a 1.6% reduction in survival and a 10–50% reduction in reproduction. ∑PCB contamination from 1950 up to 1987 was found to be too high to allow the return of white-tailed eagle as a breeding species in that period. ∑PCB and population trends simulated for 2006–2050 suggest that future population growth is still reduced. Disturbance stress resulted in a reduced population development. The combination of both toxic and disturbance stress varied from a slower population development to a catastrophical reduction in population size, where the main cause was attributed to the reduction in reproduction of 50%. Application of the model was restricted by the current lack of quantitative dose–response relationships between non-toxic stress and survival and reproduction. Nevertheless, the model provides a first step towards integrating and quantifying the impacts of multiple stressors on white-tailed eagle populations

    Analysis methods for the first KATRIN neutrino-mass measurement

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    We report on the dataset, data handling, and detailed analysis techniques of the first neutrino-mass measurement by the Karlsruhe Tritium Neutrino (KATRIN) experiment, which probes the absolute neutrino-mass scale via the β-decay kinematics of molecular tritium. The source is highly pure, cryogenic T2 gas. The β electrons are guided along magnetic field lines toward a high-resolution, integrating spectrometer for energy analysis. A silicon detector counts β electrons above the energy threshold of the spectrometer, so that a scan of the thresholds produces a precise measurement of the high-energy spectral tail. After detailed theoretical studies, simulations, and commissioning measurements, extending from the molecular final-state distribution to inelastic scattering in the source to subtleties of the electromagnetic fields, our independent, blind analyses allow us to set an upper limit of 1.1 eV on the neutrino-mass scale at a 90% confidence level. This first result, based on a few weeks of running at a reduced source intensity and dominated by statistical uncertainty, improves on prior limits by nearly a factor of two. This result establishes an analysis framework for future KATRIN measurements, and provides important input to both particle theory and cosmology

    Precision measurement of the electron energy-loss function in tritium and deuterium gas for the KATRIN experiment

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    The KATRIN experiment is designed for a direct and model-independent determination of the effective electron anti-neutrino mass via a high-precision measurement of the tritium β\beta-decay endpoint region with a sensitivity on mνm_\nu of 0.2\,eV/c2^2 (90% CL). For this purpose, the β\beta-electrons from a high-luminosity windowless gaseous tritium source traversing an electrostatic retarding spectrometer are counted to obtain an integral spectrum around the endpoint energy of 18.6\,keV. A dominant systematic effect of the response of the experimental setup is the energy loss of β\beta-electrons from elastic and inelastic scattering off tritium molecules within the source. We determined the \linebreak energy-loss function in-situ with a pulsed angular-selective and monoenergetic photoelectron source at various tritium-source densities. The data was recorded in integral and differential modes; the latter was achieved by using a novel time-of-flight technique. We developed a semi-empirical parametrization for the energy-loss function for the scattering of 18.6-keV electrons from hydrogen isotopologs. This model was fit to measurement data with a 95% T2_2 gas mixture at 30\,K, as used in the first KATRIN neutrino mass analyses, as well as a D2_2 gas mixture of 96% purity used in KATRIN commissioning runs. The achieved precision on the energy-loss function has abated the corresponding uncertainty of σ(mν2)<102eV2\sigma(m_\nu^2)<10^{-2}\,\mathrm{eV}^2 [arXiv:2101.05253] in the KATRIN neutrino-mass measurement to a subdominant level.Comment: 12 figures, 18 pages; to be submitted to EPJ

    Improved eV-scale sterile-neutrino constraints from the second KATRIN measurement campaign

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    We present the results of the light sterile neutrino search from the second Karlsruhe Tritium Neutrino (KATRIN) measurement campaign in 2019. Approaching nominal activity, 3.76×106 tritium β-electrons are analyzed in an energy window extending down to 40 eV below the tritium end point at E0=18.57  keV. We consider the 3ν+1 framework with three active and one sterile neutrino flavors. The analysis is sensitive to a fourth mass eigenstate m24≲1600  eV2 and active-to-sterile mixing |Ue4|2≳6×10−3. As no sterile-neutrino signal was observed, we provide improved exclusion contours on m24 and |Ue4|2 at 95% C.L. Our results supersede the limits from the Mainz and Troitsk experiments. Furthermore, we are able to exclude the large Δm241 solutions of the reactor antineutrino and gallium anomalies to a great extent. The latter has recently been reaffirmed by the BEST Collaboration and could be explained by a sterile neutrino with large mixing. While the remaining solutions at small Δm241 are mostly excluded by short-baseline reactor experiments, KATRIN is the only ongoing laboratory experiment to be sensitive to relevant solutions at large Δm241 through a robust spectral shape analysis
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