Game-theoretic perspective of Ping-Pong protocol

Science.gov (United States)

Kaur, Hargeet; Kumar, Atul

2018-01-01

We analyse Ping-Pong protocol from the point of view of a game. The analysis helps us in understanding the different strategies of a sender and an eavesdropper to gain the maximum payoff in the game. The study presented here characterizes strategies that lead to different Nash equilibriums. We further demonstrate the condition for Pareto optimality depending on the parameters used in the game. Moreover, we also analysed LM05 protocol and compared it with PP protocol from the point of view of a generic two-way QKD game with or without entanglement. Our results provide a deeper understanding of general two-way QKD protocols in terms of the security and payoffs of different stakeholders in the protocol.

Ping-Pong Beam Training with Hybrid Digital-Analog Antenna Arrays

DEFF Research Database (Denmark)

Manchón, Carles Navarro; Carvalho, Elisabeth De; Andersen, Jørgen Bach

2017-01-01

In this article we propose an iterative training scheme that approximates optimal beamforming between two transceivers equipped with hybrid digital-analog antenna arrays. Inspired by methods proposed for digital arrays that exploit algebraic power iterations, the proposed training procedure...... is based on a series of alternate (ping-pong) transmissions between the two devices over a reciprocal channel. During the transmissions, the devices updates their digital beamformers by conjugation and normalization operations on the received digital signal, while the analog beamformers are progressively...

Conserved generation of short products at piRNA loci

Directory of Open Access Journals (Sweden)

Khorshid Mohsen

2011-01-01

Full Text Available Abstract Background The piRNA pathway operates in animal germ lines to ensure genome integrity through retrotransposon silencing. The Piwi protein-associated small RNAs (piRNAs guide Piwi proteins to retrotransposon transcripts, which are degraded and thereby post-transcriptionally silenced through a ping-pong amplification process. Cleavage of the retrotransposon transcript defines at the same time the 5' end of a secondary piRNA that will in turn guide a Piwi protein to a primary piRNA precursor, thereby amplifying primary piRNAs. Although several studies provided evidence that this mechanism is conserved among metazoa, how the process is initiated and what enzymatic activities are responsible for generating the primary and secondary piRNAs are not entirely clear. Results Here we analyzed small RNAs from three mammalian species, seeking to gain further insight into the mechanisms responsible for the piRNA amplification loop. We found that in all these species piRNA-directed targeting is accompanied by the generation of short sequences that have a very precisely defined length, 19 nucleotides, and a specific spatial relationship with the guide piRNAs. Conclusions This suggests that the processing of the 5' product of piRNA-guided cleavage occurs while the piRNA target is engaged by the Piwi protein. Although they are not stabilized through methylation of their 3' ends, the 19-mers are abundant not only in testes lysates but also in immunoprecipitates of Miwi and Mili proteins. They will enable more accurate identification of piRNA loci in deep sequencing data sets.

A general scheme for information interception in the ping pong protocol

OpenAIRE

Zawadzki, Piotr; Miszczak, Jarosław Adam

2016-01-01

The existence of an undetectable eavesdropping of dense coded information has been already demonstrated by Pavi\\v{c}i\\'c for the quantum direct communication based on the ping-pong paradigm. However, a) the explicit scheme of the circuit is only given and no design rules are provided, b) the existence of losses is implicitly assumed, c) the attack has been formulated against qubit based protocol only and it is not clear whether it can be adapted to higher dimensional systems. These deficienci...

Respective Functions of Two Distinct Siwi Complexes Assembled during PIWI-Interacting RNA Biogenesis in Bombyx Germ Cells

Directory of Open Access Journals (Sweden)

Kazumichi M. Nishida

2015-01-01

Full Text Available PIWI-interacting RNA (piRNA biogenesis consists of two sequential steps: primary piRNA processing and the ping-pong cycle that depends on reciprocal Slicer-mediated RNA cleavage by PIWI proteins. However, the molecular functions of the factors involved remain elusive. Here, we show that RNAs cleaved by a Bombyx mori PIWI, Siwi, remain bound to the protein upon cleavage but are released by a DEAD box protein BmVasa. BmVasa copurifies with Siwi but not another PIWI BmAgo3. A lack of BmVasa does not affect primary piRNA processing but abolishes the ping-pong cycle. Siwi also forms a complex with BmSpn-E and BmQin. This complex is physically separable from the Siwi/BmVasa complex. BmSpn-E, unlike BmVasa, is necessary for primary piRNA production. We propose a model for piRNA biogenesis, where the BmSpn-E/BmQin dimer binds Siwi to function in primary piRNA processing, whereas BmVasa, by associating with Siwi, ensures target RNA release upon cleavage to facilitate the ping-pong cycle.

Correct mutual information, quantum bit error rate and secure transmission efficiency in Wojcik's eavesdropping scheme on ping-pong protocol

OpenAIRE

Zhang, Zhanjun

2004-01-01

Comment: The wrong mutual information, quantum bit error rate and secure transmission efficiency in Wojcik's eavesdropping scheme [PRL90(03)157901]on ping-pong protocol have been pointed out and corrected

Eavesdropping on the "Ping-Pong" Quantum Communication Protocol Freely in a Noise Channel

OpenAIRE

Deng, Fu-Guo; Li, Xi-Han; Li, Chun-Yan; Zhou, Ping; Zhou, Hong-Yu

2005-01-01

We introduce an attack scheme for eavesdropping the ping-pong quantum communication protocol proposed by Bostr$\\ddot{o}$m and Felbinger [Phys. Rev. Lett. \\textbf{89}, 187902 (2002)] freely in a noise channel. The vicious eavesdropper, Eve, intercepts and measures the travel photon transmitted between the sender and the receiver. Then she replaces the quantum signal with a multi-photon signal in a same state, and measures the photons return with the measuring basis with which Eve prepares the ...

Security of modified Ping-Pong protocol in noisy and lossy channel.

Science.gov (United States)

Han, Yun-Guang; Yin, Zhen-Qiang; Li, Hong-Wei; Chen, Wei; Wang, Shuang; Guo, Guang-Can; Han, Zheng-Fu

2014-05-12

The "Ping-Pong" (PP) protocol is a two-way quantum key protocol based on entanglement. In this protocol, Bob prepares one maximally entangled pair of qubits, and sends one qubit to Alice. Then, Alice performs some necessary operations on this qubit and sends it back to Bob. Although this protocol was proposed in 2002, its security in the noisy and lossy channel has not been proven. In this report, we add a simple and experimentally feasible modification to the original PP protocol, and prove the security of this modified PP protocol against collective attacks when the noisy and lossy channel is taken into account. Simulation results show that our protocol is practical.

Improved W\\'{o}jcik's Eavesdropping Attack on Ping-Pong Protocol Without Eavesdropping-Induced Channel Loss

OpenAIRE

Zhang, Zhan-jun; Li, Yong; Man, Zhong-xiao

2004-01-01

The eavesdropping scheme proposed by W\\'{o}jcik [Phys. Rev. Lett. {\\bf 90},157901(2003)] on the ping-pong protocol [Phys. Rev. Lett. {\\bf 89}, 187902(2002)] is improved by constituting a new set of attack operations. The improved scheme has a zero eavesdropping-induced channel loss and produces perfect anticorrelation. Therefore, the eavesdropper Eve can safely attack all the transmitted bits and the eavesdropping information gain can always exceed the legitimate user's information gain in th...

A General Scheme for Information Interception in the Ping-Pong Protocol

Directory of Open Access Journals (Sweden)

Piotr Zawadzki

2016-01-01

Full Text Available The existence of undetectable eavesdropping of dense coded information has been already demonstrated by Pavičić for the quantum direct communication based on the ping-pong paradigm. However, (a the explicit scheme of the circuit is only given and no design rules are provided; (b the existence of losses is implicitly assumed; (c the attack has been formulated against qubit based protocol only and it is not clear whether it can be adapted to higher dimensional systems. These deficiencies are removed in the presented contribution. A new generic eavesdropping scheme built on a firm theoretical background is proposed. In contrast to the previous approach, it does not refer to the properties of the vacuum state, so it is fully consistent with the absence of losses assumption. Moreover, the scheme applies to the communication paradigm based on signal particles of any dimensionality. It is also shown that some well known attacks are special cases of the proposed scheme.

Reconstructing Climate Change: The Model-Data Ping-Pong

Science.gov (United States)

Stocker, T. F.

2017-12-01

When Cesare Emiliani, the father of paleoceanography, made the first attempts at a quantitative reconstruction of Pleistocene climate change in the early 1950s, climate models were not yet conceived. The understanding of paleoceanographic records was therefore limited, and scientists had to resort to plausibility arguments to interpret their data. With the advent of coupled climate models in the early 1970s, for the first time hypotheses about climate processes and climate change could be tested in a dynamically consistent framework. However, only a model hierarchy can cope with the long time scales and the multi-component physical-biogeochemical Earth System. There are many examples how climate models have inspired the interpretation of paleoclimate data on the one hand, and conversely, how data have questioned long-held concepts and models. In this lecture I critically revisit a few examples of this model-data ping-pong, such as the bipolar seesaw, the mid-Holocene greenhouse gas increase, millennial and rapid CO2 changes reconstructed from polar ice cores, and the interpretation of novel paleoceanographic tracers. These examples also highlight many of the still unsolved questions and provide guidance for future research. The combination of high-resolution paleoceanographic data and modeling has never been more relevant than today. It will be the key for an appropriate risk assessment of impacts on the Earth System that are already underway in the Anthropocene.

La mode du ping-pong de 1901 à 1939 : d’un jeu de salon mondain à un sport moderne

OpenAIRE

Mousset , Kilian

2017-01-01

From the board game in the worldly salons in the beginning of the 20th century to the sought-after sport in 1932 and 1933, this ball game breaks a reductive representation of fashion, mostly about clothing. Ping-pong, which is originally a simple game box, knows two major popular movements during the first half of the 20th century. In 1902, the trend is about salon entertainment, a pretext for social distinction. Taking place after diners in the wealthy bourgeoisie, straightness of the body i...

Implementing web-based ping-pong-type e-communication to enhance staff satisfaction, multidisciplinary cooperation, and clinical effectiveness

Science.gov (United States)

Yeh, Pei-Han; Hung, Shih-Kai; Lee, Moon-Sing; Chiou, Wen-Yen; Lai, Chun-Liang; Tsai, Wei-Ta; Hsieh, Hui-Ling; Shih, Yi-Ting; Chen, Liang-Cheng; Huang, Li-Wen; Lin, Yi-An; Lin, Po-Hao; Lin, Yung-Hsiang; Liu, Dai-Wei; Hsu, Feng-Chun; Tsai, Shiang-Jiun; Liu, Jia-Chi; Chung, En-Seu; Lin, Hon-Yi

2016-01-01

Abstract Background: Frequent multidisciplinary communication is essential in conducting daily radiotherapy (RT) practice. However, traditional oral or paper-based communication has limitations. E-communication has been suggested, but its effects are still not well demarcated in the field of radiation oncology. Objects: In our web-based integrated information platform, we constructed a ping-pong-type e-communication function to transfer specific notations among multidisciplinary RT staffs. The purpose was to test whether applying this e-communication can increase effectiveness of multidisciplinary cooperation when compared with oral or paper-based practice. Staff satisfaction and clinical benefits were also demonstrated. Design and setting: A real-world quality-improving study was conducted in a large center of radiation oncology. Participants and dataset used: Before and after applying multidisciplinary e-communication (from 2014 to 2015), clinical RT staffs were surveyed for their user experience and satisfaction (n = 23). For measuring clinical effectiveness, a secondary database of irradiated head and neck cancer patients was re-analyzed for comparing RT toxicities (n = 402). Interventions: Applying ping-pong-type multidisciplinary reflective e-communication was the main intervention. Outcome measures: For measuring staff satisfaction, eight domains were surveyed, such as timeliness, convenience, and completeness. For measuring clinical effectiveness of multidisciplinary cooperation, event rates of severe (i.e., grade 3–4) RT mucositis and dermatitis were recorded. Results: Overall, when compared with oral communication only, e-communication demonstrated multiple benefits, particularly on notation-review convenience (2.00 ± 1.76 vs 9.19 ± 0.81; P communication showed statistically significant benefits on all eight domains, especially on notation-review convenience (5.05 ± 2.11 vs 9.19 ± 0.81; P communication (8.76 ± 0

Adapting playware to multiple players

DEFF Research Database (Denmark)

Þorsteinsson, Arnar Tumi; Lund, Henrik Hautop; Mastorakis, Nikos

2011-01-01

With the creation of playware as intelligent hardware and software that creates play, it is possible to adapt the play tool to the individual user, and even to multiple users playing at the same time with the play tool. In this paper, we show how it is possible to implement adaptivity in modular...... to such differences, and argues that adaptivity is needed to make games fit to the individual users in both single-player games and multi-player games. As a case study, we implemented such adaptivity on modular interactive tiles for the single-user game ColorTimer, and for the multiple-user games PingPong, in which...

Analysis of ping-pong reaction mechanisms by positional isotope exchange. Application to galactose-1-phosphate uridyltransferase

International Nuclear Information System (INIS)

Hester, L.S.; Raushel, F.M.

1987-01-01

A new positional isotope exchange method has been developed that can be used for the analysis of enzyme-catalyzed reactions which have ping-pong kinetic mechanisms. The technique can be used to measure the relative rates of ligand dissociation from enzyme-product complexes. Enzyme is incubated with the labeled substrate and an excess of the corresponding unlabeled product. The partitioning of the enzyme-product complex back toward free enzyme is determined from the rate of positional isotope exchange within the original labeled substrate. The partitioning of the enzyme-product complex forward toward free enzyme is determined from the rate of formation of totally unlabeled substrate. It has been shown that the ratio of the two rates provides a lower limit for the release of product from the enzyme-product complex. The technique has been applied to the reaction catalyzed by galactose-1-phosphate uridyltransferase. The lower limit for the release of glucose 1-phosphate from the uridyl-enzyme relative to the maximal velocity of the reverse reaction was determined to be 3.4 +/- 0.5

Transposon defense by endo-siRNAs, piRNAs and somatic pilRNAs in Drosophila: contributions of Loqs-PD and R2D2.

Directory of Open Access Journals (Sweden)

Milijana Mirkovic-Hösle

Full Text Available Transposable elements are a serious threat for genome integrity and their control via small RNA mediated silencing pathways is an ancient strategy. The fruit fly Drosophila melanogaster has two silencing activities that target transposons: endogenous siRNAs (esiRNAs or endo-siRNAs and Piwi-interacting small RNAs (piRNAs. The biogenesis of endo-siRNAs involves the Dicer-2 co-factors Loqs-PD, which acts predominantly during processing of dsRNA by Dcr-2, and R2D2, which primarily helps to direct siRNAs into the RNA interference effector Ago2. Nonetheless, loss of either protein is not sufficient to produce a phenotype comparable with a dcr-2 mutation. We provide further deep sequencing evidence supporting the notion that R2D2 and Loqs-PD have partially overlapping function. Certain transposons display a preference for either dsRBD-protein during production or loading; this appeared to correlate neither with overall abundance, classification of the transposon or a specific site of genomic origin. The endo-siRNA biogenesis pathway in germline operates according to the same principles as the existing model for the soma, and its impairment does not significantly affect piRNAs. Expanding the analysis, we confirmed the occurrence of somatic piRNA-like RNAs (pilRNAs that show a ping-pong signature. We detected expression of the Piwi-family protein mRNAs only barely above background, indicating that the somatic pilRNAs may arise from a small sub-population of somatic cells that express a functional piRNA pathway.

Ping pong in Phuket: the intersections of tourism, porn and the future

Directory of Open Access Journals (Sweden)

Michelle Stella Mars

2017-04-01

Full Text Available Purpose – Sex tourism is well documented in the literature, but what about porn tourism? Whether it is a Ping Pong show in Phuket or the Banana show in Amsterdam, porn and tourism have an encounter and gaze no different from the Mona Lisa in the Louvre or magnificent views of New Zealand’s Southern Alps. The paper aims to discuss these issues. Design/methodology/approach – This paper explores the intersections of tourism, porn and the future as a conceptual framework. Findings – Four intersections are derived from the conceptual framework. Intersection 1, the Future of Tourism, portrays the evolution of tourism and explores its technological future. Interaction 2, Porn in Tourism, distinguishes between soft- and hard-core porn tourism. Intersection 3, Portraying Porn as a Future Dimension, delves into futurism, science fiction and fantasy. The fourth intersection, the Future Gaze, conveys the thrust of the paper by exploring how technological advancement blends with authenticity and reality. Thus the porn tourist seeks both the visual and the visceral pleasures of desire. The paper concludes with four future gazes of porn tourism, The Allure of Porn, The Porn Bubble, Porn as Liminal Experience and Hardcore. Originality/value – The originality of this paper is that this is the first paper to systematically examine porn tourism beyond sex tourism overlaying with a futures dimension. Porn tourists actively seek to experience both visual and visceral pleasures. Tourism and pornography both begin with the gaze. The gaze is an integral component of futures thinking. Technology is changing us, making us smarter, driving our thirst for liminal experiences. Like the transition from silent movies to talking pictures the porn tourism experience of the future is likely to involve more of the bodily senses.

Division of labor as an emergent phenomenon of social coordination: The example of playing doubles-pong : The example of playing doubles-pong

NARCIS (Netherlands)

Benerink, Niek H.; Zaal, Frank T J M; Casanova, Remy; Bonnardel, Nathalie; Bootsma, Reinoud J

In many daily situations, our behavior is coordinated with that of others. This study investigated this coordination in a doubles-pong task. In this task, two participants each controlled a paddle that could move laterally near the bottom of a shared computer screen. With their paddles, the players

Security of modified Ping-Pong protocol in noisy and lossy channel

OpenAIRE

Han, Yun-Guang; Yin, Zhen-Qiang; Li, Hong-Wei; Chen, Wei; Wang, Shuang; Guo, Guang-Can; Han, Zheng-Fu

2014-01-01

The “Ping-Pong” (PP) protocol is a two-way quantum key protocol based on entanglement. In this protocol, Bob prepares one maximally entangled pair of qubits, and sends one qubit to Alice. Then, Alice performs some necessary operations on this qubit and sends it back to Bob. Although this protocol was proposed in 2002, its security in the noisy and lossy channel has not been proven. In this report, we add a simple and experimentally feasible modification to the original PP protocol, and prove ...

Guardian small RNAs and sex determination.

Science.gov (United States)

Katsuma, Susumu; Kawamoto, Munetaka; Kiuchi, Takashi

2014-01-01

The W chromosome of the silkworm Bombyx mori has been known to determine femaleness for more than 80 years. However, the feminizing gene has not been molecularly identified, because the B. mori W chromosome is almost fully occupied by a large number of transposable elements. The W chromosome-derived feminizing factor of B. mori was recently shown to be a female-specific PIWI-interacting RNA (piRNA). piRNAs are small RNAs that potentially repress invading "non-self" elements (e.g., transposons and virus-like elements) by associating with PIWI proteins. Our results revealed that female-specific piRNA precursors, which we named Fem, are transcribed from the sex-determining region of the W chromosome at the early embryonic stage and are processed into a single mature piRNA (Fem piRNA). Fem piRNA forms a complex with Siwi (silkworm Piwi), which cleaves a protein-coding mRNA transcribed from the Z chromosome. RNA interference of this Z-linked gene, which we named Masc, revealed that this gene encodes a protein required for masculinization and dosage compensation. Fem and Masc both participate in the ping-pong cycle of the piRNA amplification loop by associating with the 2 B. mori PIWI proteins Siwi and BmAgo3 (silkworm Ago3), respectively, indicating that the piRNA-mediated interaction between the 2 sex chromosomes is the primary signal for the B. mori sex determination cascade. Fem is a non-transposable repetitive sequence on the W chromosome, whereas Masc is a single-copy protein-coding gene. It is of great interest how the piRNA system recognizes "self "Masc mRNA as "non-self" RNA.

Minotaur is critical for primary piRNA biogenesis.

Science.gov (United States)

Vagin, Vasily V; Yu, Yang; Jankowska, Anna; Luo, Yicheng; Wasik, Kaja A; Malone, Colin D; Harrison, Emily; Rosebrock, Adam; Wakimoto, Barbara T; Fagegaltier, Delphine; Muerdter, Felix; Hannon, Gregory J

2013-08-01

Piwi proteins and their associated small RNAs are essential for fertility in animals. In part, this is due to their roles in guarding germ cell genomes against the activity of mobile genetic elements. piRNA populations direct Piwi proteins to silence transposon targets and, as such, form a molecular code that discriminates transposons from endogenous genes. Information ultimately carried by piRNAs is encoded within genomic loci, termed piRNA clusters. These give rise to long, single-stranded, primary transcripts that are processed into piRNAs. Despite the biological importance of this pathway, neither the characteristics that define a locus as a source of piRNAs nor the mechanisms that catalyze primary piRNA biogenesis are well understood. We searched an EMS-mutant collection annotated for fertility phenotypes for genes involved in the piRNA pathway. Twenty-seven homozygous sterile strains showed transposon-silencing defects. One of these, which strongly impacted primary piRNA biogenesis, harbored a causal mutation in CG5508, a member of the Drosophila glycerol-3-phosphate O-acetyltransferase (GPAT) family. These enzymes catalyze the first acylation step on the path to the production of phosphatidic acid (PA). Though this pointed strongly to a function for phospholipid signaling in the piRNA pathway, a mutant form of CG5508, which lacks the GPAT active site, still functions in piRNA biogenesis. We have named this new biogenesis factor Minotaur.

Minotaur is critical for primary piRNA biogenesis

Science.gov (United States)

Vagin, Vasily V.; Yu, Yang; Jankowska, Anna; Luo, Yicheng; Wasik, Kaja A.; Malone, Colin D.; Harrison, Emily; Rosebrock, Adam; Wakimoto, Barbara T.; Fagegaltier, Delphine; Muerdter, Felix; Hannon, Gregory J.

2013-01-01

Piwi proteins and their associated small RNAs are essential for fertility in animals. In part, this is due to their roles in guarding germ cell genomes against the activity of mobile genetic elements. piRNA populations direct Piwi proteins to silence transposon targets and, as such, form a molecular code that discriminates transposons from endogenous genes. Information ultimately carried by piRNAs is encoded within genomic loci, termed piRNA clusters. These give rise to long, single-stranded, primary transcripts that are processed into piRNAs. Despite the biological importance of this pathway, neither the characteristics that define a locus as a source of piRNAs nor the mechanisms that catalyze primary piRNA biogenesis are well understood. We searched an EMS-mutant collection annotated for fertility phenotypes for genes involved in the piRNA pathway. Twenty-seven homozygous sterile strains showed transposon-silencing defects. One of these, which strongly impacted primary piRNA biogenesis, harbored a causal mutation in CG5508, a member of the Drosophila glycerol-3-phosphate O-acetyltransferase (GPAT) family. These enzymes catalyze the first acylation step on the path to the production of phosphatidic acid (PA). Though this pointed strongly to a function for phospholipid signaling in the piRNA pathway, a mutant form of CG5508, which lacks the GPAT active site, still functions in piRNA biogenesis. We have named this new biogenesis factor Minotaur. PMID:23788724

Characterization of piRNAs across postnatal development in mouse brain

KAUST Repository

Ghosheh, Yanal; Seridi, Loqmane; Ryu, Tae Woo; Takahashi, Hazuki; Orlando, Valerio; Carninci, Piero; Ravasi, Timothy

2016-01-01

PIWI-interacting RNAs (piRNAs) are responsible for maintaining the genome stability by silencing retrotransposons in germline tissues– where piRNAs were first discovered and thought to be restricted. Recently, novel functions were reported for piRNAs in germline and somatic cells. Using deep sequencing of small RNAs and CAGE of postnatal development of mouse brain, we identified piRNAs only in adult mouse brain. These piRNAs have similar sequence length as those of MILI-bound piRNAs. In addition, we predicted novel candidate regulators and putative targets of adult brain piRNAs.

Characterization of piRNAs across postnatal development in mouse brain

KAUST Repository

Ghosheh, Yanal

2016-04-26

PIWI-interacting RNAs (piRNAs) are responsible for maintaining the genome stability by silencing retrotransposons in germline tissues– where piRNAs were first discovered and thought to be restricted. Recently, novel functions were reported for piRNAs in germline and somatic cells. Using deep sequencing of small RNAs and CAGE of postnatal development of mouse brain, we identified piRNAs only in adult mouse brain. These piRNAs have similar sequence length as those of MILI-bound piRNAs. In addition, we predicted novel candidate regulators and putative targets of adult brain piRNAs.

Elucidating the Small Regulatory RNA Repertoire of the Sea Anemone Anemonia viridis Based on Whole Genome and Small RNA Sequencing.

Science.gov (United States)

Urbarova, Ilona; Patel, Hardip; Forêt, Sylvain; Karlsen, Bård Ove; Jørgensen, Tor Erik; Hall-Spencer, Jason M; Johansen, Steinar D

2018-02-01

Cnidarians harbor a variety of small regulatory RNAs that include microRNAs (miRNAs) and PIWI-interacting RNAs (piRNAs), but detailed information is limited. Here, we report the identification and expression of novel miRNAs and putative piRNAs, as well as their genomic loci, in the symbiotic sea anemone Anemonia viridis. We generated a draft assembly of the A. viridis genome with putative size of 313 Mb that appeared to be composed of about 36% repeats, including known transposable elements. We detected approximately equal fractions of DNA transposons and retrotransposons. Deep sequencing of small RNA libraries constructed from A. viridis adults sampled at a natural CO2 gradient off Vulcano Island, Italy, identified 70 distinct miRNAs. Eight were homologous to previously reported miRNAs in cnidarians, whereas 62 appeared novel. Nine miRNAs were recognized as differentially expressed along the natural seawater pH gradient. We found a highly abundant and diverse population of piRNAs, with a substantial fraction showing ping-pong signatures. We identified nearly 22% putative piRNAs potentially targeting transposable elements within the A. viridis genome. The A. viridis genome appeared similar in size to that of other hexacorals with a very high divergence of transposable elements resembling that of the sea anemone genus Exaiptasia. The genome encodes and expresses a high number of small regulatory RNAs, which include novel miRNAs and piRNAs. Differentially expressed small RNAs along the seawater pH gradient indicated regulatory gene responses to environmental stressors. © The Author(s) 2018. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Natural variation of piRNA expression affects immunity to transposable elements.

Directory of Open Access Journals (Sweden)

Sergei Ryazansky

2017-04-01

Full Text Available In the Drosophila germline, transposable elements (TEs are silenced by PIWI-interacting RNA (piRNA that originate from distinct genomic regions termed piRNA clusters and are processed by PIWI-subfamily Argonaute proteins. Here, we explore the variation in the ability to restrain an alien TE in different Drosophila strains. The I-element is a retrotransposon involved in the phenomenon of I-R hybrid dysgenesis in Drosophila melanogaster. Genomes of R strains do not contain active I-elements, but harbour remnants of ancestral I-related elements. The permissivity to I-element activity of R females, called reactivity, varies considerably in natural R populations, indicating the existence of a strong natural polymorphism in defense systems targeting transposons. To reveal the nature of such polymorphisms, we compared ovarian small RNAs between R strains with low and high reactivity and show that reactivity negatively correlates with the ancestral I-element-specific piRNA content. Analysis of piRNA clusters containing remnants of I-elements shows increased expression of the piRNA precursors and enrichment by the Heterochromatin Protein 1 homolog, Rhino, in weak R strains, which is in accordance with stronger piRNA expression by these regions. To explore the nature of the differences in piRNA production, we focused on two R strains, weak and strong, and showed that the efficiency of maternal inheritance of piRNAs as well as the I-element copy number are very similar in both strains. At the same time, germline and somatic uni-strand piRNA clusters generate more piRNAs in strains with low reactivity, suggesting the relationship between the efficiency of primary piRNA production and variable response to TE invasions. The strength of adaptive genome defense is likely driven by naturally occurring polymorphisms in the rapidly evolving piRNA pathway proteins. We hypothesize that hyper-efficient piRNA production is contributing to elimination of a telomeric

Recursive Ping-Pong Protocols

DEFF Research Database (Denmark)

Huttel, Hans; Srba, Jiri

2004-01-01

and bisimulation checking. Our main result is that our channel-free and memory-less calculus is Turing powerful, assuming that at least three principals are involved. We also investigate the expressive power of the calculus in the case of two participants. Here, our main results are that reachability and, under...

Detection of PIWI and piRNAs in the mitochondria of mammalian cancer cells

International Nuclear Information System (INIS)

Kwon, ChangHyuk; Tak, Hyosun; Rho, Mina; Chang, Hae Ryung; Kim, Yon Hui; Kim, Kyung Tae; Balch, Curt; Lee, Eun Kyung; Nam, Seungyoon

2014-01-01

Highlights: • piRNA sequences were mapped to human mitochondrial (mt) genome. • We inspected small RNA-Seq datasets from somatic cell mt subcellular fractions. • Piwi and piRNA transcripts are present in mammalian somatic cancer cell mt fractions. - Abstract: Piwi-interacting RNAs (piRNAs) are 26–31 nt small noncoding RNAs that are processed from their longer precursor transcripts by Piwi proteins. Localization of Piwi and piRNA has been reported mostly in nucleus and cytoplasm of higher eukaryotes germ-line cells, where it is believed that known piRNA sequences are located in repeat regions of nuclear genome in germ-line cells. However, localization of PIWI and piRNA in mammalian somatic cell mitochondria yet remains largely unknown. We identified 29 piRNA sequence alignments from various regions of the human mitochondrial genome. Twelve out 29 piRNA sequences matched stem-loop fragment sequences of seven distinct tRNAs. We observed their actual expression in mitochondria subcellular fractions by inspecting mitochondrial-specific small RNA-Seq datasets. Of interest, the majority of the 29 piRNAs overlapped with multiple longer transcripts (expressed sequence tags) that are unique to the human mitochondrial genome. The presence of mature piRNAs in mitochondria was detected by qRT-PCR of mitochondrial subcellular RNAs. Further validation showed detection of Piwi by colocalization using anti-Piwil1 and mitochondria organelle-specific protein antibodies

Detection of PIWI and piRNAs in the mitochondria of mammalian cancer cells

Energy Technology Data Exchange (ETDEWEB)

Kwon, ChangHyuk, E-mail: netbuyer@hanmail.net [Cancer Genomics Branch, National Cancer Center, Goyang 410-769 (Korea, Republic of); Tak, Hyosun, E-mail: chuberry@naver.com [Department of Biochemistry, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Rho, Mina, E-mail: minarho@hanyang.ac.kr [Department of Computer Science, Hanyang University, Seoul 133-791 (Korea, Republic of); Chang, Hae Ryung, E-mail: heyhae@ncc.re.kr [New Experimental Therapeutics Branch, National Cancer Center, Goyang 410-769 (Korea, Republic of); Kim, Yon Hui, E-mail: yhkim@ncc.re.kr [New Experimental Therapeutics Branch, National Cancer Center, Goyang 410-769 (Korea, Republic of); Kim, Kyung Tae, E-mail: bioktkim@ncc.re.kr [Molecular Epidemiology Branch, National Cancer Center, Goyang 410-769 (Korea, Republic of); Balch, Curt, E-mail: curt.balch@gmail.com [Medical Sciences Program, Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Bloomington, IN 47405 (United States); Lee, Eun Kyung, E-mail: leeek@catholic.ac.kr [Department of Biochemistry, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Nam, Seungyoon, E-mail: seungyoon.nam@ncc.re.kr [Cancer Genomics Branch, National Cancer Center, Goyang 410-769 (Korea, Republic of)

2014-03-28

Highlights: • piRNA sequences were mapped to human mitochondrial (mt) genome. • We inspected small RNA-Seq datasets from somatic cell mt subcellular fractions. • Piwi and piRNA transcripts are present in mammalian somatic cancer cell mt fractions. - Abstract: Piwi-interacting RNAs (piRNAs) are 26–31 nt small noncoding RNAs that are processed from their longer precursor transcripts by Piwi proteins. Localization of Piwi and piRNA has been reported mostly in nucleus and cytoplasm of higher eukaryotes germ-line cells, where it is believed that known piRNA sequences are located in repeat regions of nuclear genome in germ-line cells. However, localization of PIWI and piRNA in mammalian somatic cell mitochondria yet remains largely unknown. We identified 29 piRNA sequence alignments from various regions of the human mitochondrial genome. Twelve out 29 piRNA sequences matched stem-loop fragment sequences of seven distinct tRNAs. We observed their actual expression in mitochondria subcellular fractions by inspecting mitochondrial-specific small RNA-Seq datasets. Of interest, the majority of the 29 piRNAs overlapped with multiple longer transcripts (expressed sequence tags) that are unique to the human mitochondrial genome. The presence of mature piRNAs in mitochondria was detected by qRT-PCR of mitochondrial subcellular RNAs. Further validation showed detection of Piwi by colocalization using anti-Piwil1 and mitochondria organelle-specific protein antibodies.

Early embryogenesis-specific expression of the rice transposon Ping enhances amplification of the MITE mPing.

Directory of Open Access Journals (Sweden)

Shota Teramoto

2014-06-01

Full Text Available Miniature inverted-repeat transposable elements (MITEs are numerically predominant transposable elements in the rice genome, and their activities have influenced the evolution of genes. Very little is known about how MITEs can rapidly amplify to thousands in the genome. The rice MITE mPing is quiescent in most cultivars under natural growth conditions, although it is activated by various stresses, such as tissue culture, gamma-ray irradiation, and high hydrostatic pressure. Exceptionally in the temperate japonica rice strain EG4 (cultivar Gimbozu, mPing has reached over 1000 copies in the genome, and is amplifying owing to its active transposition even under natural growth conditions. Being the only active MITE, mPing in EG4 is an appropriate material to study how MITEs amplify in the genome. Here, we provide important findings regarding the transposition and amplification of mPing in EG4. Transposon display of mPing using various tissues of a single EG4 plant revealed that most de novo mPing insertions arise in embryogenesis during the period from 3 to 5 days after pollination (DAP, and a large majority of these insertions are transmissible to the next generation. Locus-specific PCR showed that mPing excisions and insertions arose at the same time (3 to 5 DAP. Moreover, expression analysis and in situ hybridization analysis revealed that Ping, an autonomous partner for mPing, was markedly up-regulated in the 3 DAP embryo of EG4, whereas such up-regulation of Ping was not observed in the mPing-inactive cultivar Nipponbare. These results demonstrate that the early embryogenesis-specific expression of Ping is responsible for the successful amplification of mPing in EG4. This study helps not only to elucidate the whole mechanism of mPing amplification but also to further understand the contribution of MITEs to genome evolution.

An Ancient Transcription Factor Initiates the Burst of piRNA Production During Early Meiosis in Mouse Testes

Science.gov (United States)

Li, Xin Zhiguo; Roy, Christian K.; Dong, Xianjun; Bolcun-Filas, Ewelina; Wang, Jie; Han, Bo W.; Xu, Jia; Moore, Melissa J.; Schimenti, John C.; Weng, Zhiping; Zamore, Phillip D.

2013-01-01

SUMMARY Animal germ cells produce PIWI-interacting RNAs (piRNAs), small silencing RNAs that suppress transposons and enable gamete maturation. Mammalian transposon-silencing piRNAs accumulate early in spermatogenesis, whereas pachytene piRNAs are produced later during post-natal spermatogenesis and account for >95% of all piRNAs in the adult mouse testis. Mutants defective for pachytene piRNA pathway proteins fail to produce mature sperm, but neither the piRNA precursor transcripts nor the trigger for pachytene piRNA production is known. Here, we show that the transcription factor A-MYB initiates pachytene piRNA production. A-MYB drives transcription of both pachytene piRNA precursor RNAs and the mRNAs for core piRNA biogenesis factors, including MIWI, the protein through which pachytene piRNAs function. A-MYB regulation of piRNA pathway proteins and piRNA genes creates a coherent feed-forward loop that ensures the robust accumulation of pachytene piRNAs. This regulatory circuit, which can be detected in rooster testes, likely predates the divergence of birds and mammals. PMID:23523368

The genetic makeup of the Drosophila piRNA pathway.

Science.gov (United States)

Handler, Dominik; Meixner, Katharina; Pizka, Manfred; Lauss, Kathrin; Schmied, Christopher; Gruber, Franz Sebastian; Brennecke, Julius

2013-06-06

The piRNA (PIWI-interacting RNA) pathway is a small RNA silencing system that acts in animal gonads and protects the genome against the deleterious influence of transposons. A major bottleneck in the field is the lack of comprehensive knowledge of the factors and molecular processes that constitute this pathway. We conducted an RNAi screen in Drosophila and identified ~50 genes that strongly impact the ovarian somatic piRNA pathway. Many identified genes fall into functional categories that indicate essential roles for mitochondrial metabolism, RNA export, the nuclear pore, transcription elongation, and chromatin regulation in the pathway. Follow-up studies on two factors demonstrate that components acting at distinct hierarchical levels of the pathway were identified. Finally, we define CG2183/Gasz as an essential primary piRNA biogenesis factor in somatic and germline cells. Based on the similarities between insect and vertebrate piRNA pathways, our results have far-reaching implications for the understanding of this conserved genome defense system. Copyright © 2013 Elsevier Inc. All rights reserved.

Discovery and Characterization of piRNAs in the Human Fetal Ovary

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Zev Williams

2015-10-01

Full Text Available Piwi-interacting RNAs (piRNAs, a class of 26- to 32-nt non-coding RNAs (ncRNAs, function in germline development, transposon silencing, and epigenetic regulation. We performed deep sequencing and annotation of untreated and periodate-treated small RNA cDNA libraries from human fetal and adult germline and reference somatic tissues. This revealed abundant piRNAs originating from 150 piRNA-encoding genes, including some exhibiting gender-specific expression, in fetal ovary and adult testis—developmental periods coinciding with mitotic cell divisions expanding fetal germ cells prior to meiotic divisions. The absence of reads mapping uniquely to annotated piRNA genes demonstrated their paucity in fetal testis and adult ovary and absence in somatic tissues. We curated human piRNA-expressing regions and defined their precise borders and observed piRNA-guided cleavage of transcripts antisense to some piRNA-producing genes. This study provides insights into sex-specific mammalian piRNA expression and function and serves as a reference for human piRNA analysis and annotation.

piRNA analysis framework from small RNA-Seq data by a novel cluster prediction tool - PILFER.

Science.gov (United States)

Ray, Rishav; Pandey, Priyanka

2017-12-19

With the increasing number of studies focusing on PIWI-interacting RNA (piRNAs), it is now pertinent to develop efficient tools dedicated towards piRNA analysis. We have developed a novel cluster prediction tool called PILFER (PIrna cLuster FindER), which can accurately predict piRNA clusters from small RNA sequencing data. PILFER is an open source, easy to use tool, and can be executed even on a personal computer with minimum resources. It uses a sliding-window mechanism by integrating the expression of the reads along with the spatial information to predict the piRNA clusters. We have additionally defined a piRNA analysis pipeline incorporating PILFER to detect and annotate piRNAs and their clusters from raw small RNA sequencing data and implemented it on publicly available data from healthy germline and somatic tissues. We compared PILFER with other existing piRNA cluster prediction tools and found it to be statistically more accurate and superior in many aspects such as the robustness of PILFER clusters is higher and memory efficiency is more. Overall, PILFER provides a fast and accurate solution to piRNA cluster prediction. Copyright © 2017 Elsevier Inc. All rights reserved.

PIWIs Go Viral: Arbovirus-Derived piRNAs in Vector Mosquitoes.

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Pascal Miesen

2016-12-01

Full Text Available Vector mosquitoes are responsible for transmission of the majority of arthropod-borne (arbo- viruses. Virus replication in these vectors needs to be sufficiently high to permit efficient virus transfer to vertebrate hosts. The mosquito immune response therefore is a key determinant for arbovirus transmission. Mosquito antiviral immunity is primarily mediated by the small interfering RNA pathway. Besides this well-established antiviral machinery, the PIWI-interacting RNA (piRNA pathway processes viral RNA into piRNAs. In recent years, significant progress has been made in characterizing the biogenesis and function of these viral piRNAs. In this review, we discuss these developments, identify knowledge gaps, and suggest directions for future research.

Eavesdropping on the Bostroem-Filbinger Communication Protocol in Noisy Quantum Channel

OpenAIRE

Cai, Qing-yu

2004-01-01

We show an eavesdropping scheme on Bostr\\UNICODE{0xf6}m-Felbinger communication protocol (called ping-pong protocol) [Phys. Rev. Lett. 89, 187902 (2002)] in an ideal quantum channel. A measurement attack can be perfectly used to eavesdrop Alice's information instead of a most general quantum operation attack. In a noisy quantum channel, the direct communication is forbidden. We present a quantum key distribution protocol based on the ping-pong protocol, which can be used in a low noisy quantu...

PingFederate

Data.gov (United States)

US Agency for International Development — PingFederate Server provides Identity Federation and Single Sign On Capabilities. Federated identity management (or identity federation) enables enterprises to...

The small RNA content of human sperm reveals pseudogene-derived piRNAs complementary to protein-coding genes

DEFF Research Database (Denmark)

Pantano, Lorena; Jodar, Meritxell; Bak, Mads

2015-01-01

-specific genes. The most abundant class of small noncoding RNAs in sperm are PIWI-interacting RNAs (piRNAs). Surprisingly, we found that human sperm cells contain piRNAs processed from pseudogenes. Clusters of piRNAs from human testes contain pseudogenes transcribed in the antisense strand and processed...... into small RNAs. Several human protein-coding genes contain antisense predicted targets of pseudogene-derived piRNAs in the male germline and these piRNAs are still found in mature sperm. Our study provides the most extensive data set and annotation of human sperm small RNAs to date and is a resource...... for further functional studies on the roles of sperm small RNAs. In addition, we propose that some of the pseudogene-derived human piRNAs may regulate expression of their parent gene in the male germline....

Characterization of the Zika virus induced small RNA response in Aedes aegypti cells.

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Margus Varjak

2017-10-01

Full Text Available RNA interference (RNAi controls arbovirus infections in mosquitoes. Two different RNAi pathways are involved in antiviral responses: the PIWI-interacting RNA (piRNA and exogenous short interfering RNA (exo-siRNA pathways, which are characterized by the production of virus-derived small RNAs of 25-29 and 21 nucleotides, respectively. The exo-siRNA pathway is considered to be the key mosquito antiviral response mechanism. In Aedes aegypti-derived cells, Zika virus (ZIKV-specific siRNAs were produced and loaded into the exo-siRNA pathway effector protein Argonaute 2 (Ago2; although the knockdown of Ago2 did not enhance virus replication. Enhanced ZIKV replication was observed in a Dcr2-knockout cell line suggesting that the exo-siRNA pathway is implicated in the antiviral response. Although ZIKV-specific piRNA-sized small RNAs were detected, these lacked the characteristic piRNA ping-pong signature motif and were bound to Ago3 but not Piwi5 or Piwi6. Silencing of PIWI proteins indicated that the knockdown of Ago3, Piwi5 or Piwi6 did not enhance ZIKV replication and only Piwi4 displayed antiviral activity. We also report that the expression of ZIKV capsid (C protein amplified the replication of a reporter alphavirus; although, unlike yellow fever virus C protein, it does not inhibit the exo-siRNA pathway. Our findings elucidate ZIKV-mosquito RNAi interactions that are important for understanding its spread.

Ping-pong champion with adrenal insufficiency

Science.gov (United States)

Arima, Hiroshi; Imamine, Rui; Oiso, Yutaka

2009-01-01

A 62-year-old Japanese man, a bronze medal winner in the World Championship of table tennis when in his 20s, was diagnosed with secondary adrenocortical insufficiency due to isolated adrenocorticotropic hormone (ACTH) deficiency, and steroid administration was started. About 1 year after the diagnosis, he took part in a table tennis championship which was open to those 40 years or older. He took 10 mg hydrocortisone after breakfast as usual, played 10 matches, each of which took 20–30 min, and won the championship in about 8 h. Since the man could not always win the gruelling competition even when in his 50s, it is suggested that extra steroid hormone is not necessary for patients with adrenocortical insufficiency due to ACTH deficiency in order to successfully engage in sports requiring such intensity and endurance. PMID:21686433

An Atmospheric Pressure Ping-Pong "Ballometer"

Science.gov (United States)

Kazachkov, Alexander; Kryuchkov, Dmitriy; Willis, Courtney; Moore, John C.

2006-01-01

Classroom experiments on atmospheric pressure focus largely on demonstrating its existence, often in a most impressive way. A series of amusing physics demonstrations is widely known and practiced by educators teaching the topic. However, measuring the value of atmospheric pressure(P[subscript atm]) is generally done in a rather mundane way,…

piRNA Profiling of Dengue Virus Type 2-Infected Asian Tiger Mosquito and Midgut Tissues

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Yanhai Wang

2018-04-01

Full Text Available The Asian tiger mosquito, Aedes albopictus, is a competent vector for the majority of arboviruses. The mosquito innate immune response is a primary determinant for arthropod-borne virus transmission, and the midgut is the first barrier to pathogen transmission. Mosquito antiviral immunity is primarily mediated by the small interfering RNA pathway. However, the roles that the P-element induced wimpy testis (PIWI-interacting RNA (piRNA pathway play in antiviral immunity in Ae. albopictus and its midgut still need further exploration. This study aimed to explore the profiles of both viral-derived and host-originated piRNAs in the whole body and midgut infected with Dengue virus 2 (DENV-2 in Ae. albopictus, and to elucidate gene expression profile differences of the PIWI protein family between adult females and their midguts. A deep sequencing-based method was used to identify and analyze small non-coding RNAs, especially the piRNA profiles in DENV-2-infected Ae. albopictus and its midgut. The top-ranked, differentially-expressed piRNAs were further validated using Stem-loop qRT-PCR. Bioinformatics analyses and reverse-transcription PCR (RT-PCR methods were used to detect PIWI protein family members, and their expression profiles. DENV-2 derived piRNAs (vpiRNA, 24–30 nts were observed in both infected Ae. albopictus and its midgut; however, only vpiRNA in the whole-body library had a weak preference for adenine at position 10 (10A in the sense molecules as a feature of secondary piRNA. These vpiRNAs were not equally distributed, instead they were derived from a few specific regions of the genome, especially several hot spots, and displayed an obvious positive strand bias. We refer to the differentially expressed host piRNAs after DENV infection as virus-induced host endogenous piRNAs (vepiRNAs. However, we found that vepiRNAs were abundant in mosquito whole-body tissue, but deficient in the midgut. A total of eleven PIWI family genes were

Ping Zhang

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. PING ZHANG. Articles written in Bulletin of Materials Science. Volume 36 Issue 6 November 2013 pp 1073-1077. Intrinsic structure and friction properties of graphene and graphene oxide nanosheets studied by scanning probe microscopy · Yan-Huai Ding Hu-Ming Ren Fei-Hu ...

Complete Subsurface Elemental Composition Measurements With PING

Science.gov (United States)

Parsons, A. M.

2012-01-01

The Probing In situ with Neutrons and Gamma rays (PING) instrument will measure the complete bulk elemental composition of the subsurface of Mars as well as any other solid planetary body. PING can thus be a highly effective tool for both detailed local geochemistry science investigations and precision measurements of Mars subsurface reSOurces in preparation for future human exploration. As such, PING is thus fully capable of meeting a majority of both ncar and far term elements in Challenge #1 presented for this conference. Measuring the ncar subsurface composition of Mars will enable many of the MEPAG science goals and will be key to filling an important Strategic Knowledge Gap with regard to In situ Resources Utilization (ISRU) needs for human exploration. [1, 2] PING will thus fill an important niche in the Mars Exploration Program.

Distinct functions for the Drosophila piRNA pathway in genome maintenance and telomere protection.

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Jaspreet S Khurana

2010-12-01

Full Text Available Transposons and other selfish DNA elements can be found in all phyla, and mobilization of these elements can compromise genome integrity. The piRNA (PIWI-interacting RNA pathway silences transposons in the germline, but it is unclear if this pathway has additional functions during development. Here we show that mutations in the Drosophila piRNA pathway genes, armi, aub, ago3, and rhi, lead to extensive fragmentation of the zygotic genome during the cleavage stage of embryonic divisions. Additionally, aub and armi show defects in telomere resolution during meiosis and the cleavage divisions; and mutations in lig-IV, which disrupt non-homologous end joining, suppress these fusions. By contrast, lig-IV mutations enhance chromosome fragmentation. Chromatin immunoprecipitation studies show that aub and armi mutations disrupt telomere binding of HOAP, which is a component of the telomere protection complex, and reduce expression of a subpopulation of 19- to 22-nt telomere-specific piRNAs. Mutations in rhi and ago3, by contrast, do not block HOAP binding or production of these piRNAs. These findings uncover genetically separable functions for the Drosophila piRNA pathway. The aub, armi, rhi, and ago3 genes silence transposons and maintain chromosome integrity during cleavage-stage embryonic divisions. However, the aub and armi genes have an additional function in assembly of the telomere protection complex.

Identification and verification of potential piRNAs from domesticated yak testis.

Science.gov (United States)

Gong, Jishang; Zhang, Quanwei; Wang, Qi; Ma, Youji; Du, Jiaxiang; Zhang, Yong; Zhao, Xingxu

2018-02-01

PIWI-interacting RNAs (piRNA) are small non-coding RNA molecules expressed in animal germ cells that interact with PIWI family proteins to form RNA-protein complexes involved in epigenetic and post-transcriptional gene silencing of retrotransposons and other genetic elements in germ line cells, including reproductive stem cell self-sustainment, differentiation, meiosis and spermatogenesis. In the present study, we performed high-throughput sequencing of piRNAs in testis samples from yaks in different stages of sexual maturity. Deep sequencing of the small RNAs (18-40 nt in length) yielded 4,900,538 unique reads from a total of 53,035,635 reads. We identified yak small RNAs (18-30 nt) and performed functional characterization. Yak small RNAs showed a bimodal length distribution, with two peaks at 22 nt and >28 nt. More than 80% of the 3,106,033 putative piRNAs were mapped to 4637 piRNA-producing genomic clusters using RPKM. 6388 candidate piRNAs were identified from clean reads and the annotations were compared with the yak reference genome repeat region. Integrated network analysis suggested that some differentially expressed genes were involved in spermatogenesis through ECM-receptor interaction and PI3K-Akt signaling pathways. Our data provide novel insights into the molecular expression and regulation similarities and diversities in spermatogenesis and testicular development in yaks at different stages of sexual maturity. © 2018 The authors.

Silencing of Transposable Elements by piRNAs in Drosophila: An Evolutionary Perspective.

Science.gov (United States)

Luo, Shiqi; Lu, Jian

2017-06-01

Transposable elements (TEs) are DNA sequences that can move within the genome. TEs have greatly shaped the genomes, transcriptomes, and proteomes of the host organisms through a variety of mechanisms. However, TEs generally disrupt genes and destabilize the host genomes, which substantially reduce fitness of the host organisms. Understanding the genomic distribution and evolutionary dynamics of TEs will greatly deepen our understanding of the TE-mediated biological processes. Most TE insertions are highly polymorphic in Drosophila melanogaster, providing us a good system to investigate the evolution of TEs at the population level. Decades of theoretical and experimental studies have well established "transposition-selection" population genetics model, which assumes that the equilibrium between TE replication and purifying selection determines the copy number of TEs in the genome. In the last decade, P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs) were demonstrated to be master repressors of TE activities in Drosophila. The discovery of piRNAs revolutionized our understanding of TE repression, because it reveals that the host organisms have evolved an adaptive mechanism to defend against TE invasion. Tremendous progress has been made to understand the molecular mechanisms by which piRNAs repress active TEs, although many details in this process remain to be further explored. The interaction between piRNAs and TEs well explains the molecular mechanisms underlying hybrid dysgenesis for the I-R and P-M systems in Drosophila, which have puzzled evolutionary biologists for decades. The piRNA repression pathway provides us an unparalleled system to study the co-evolutionary process between parasites and host organisms. Copyright © 2017 Beijing Institute of Genomics, Chinese Academy of Sciences and Genetics Society of China. Production and hosting by Elsevier B.V. All rights reserved.

Retrotransposon-centered analysis of piRNA targeting shows a shift from active to passive retrotransposon transcription in developing mouse testes

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Mourier Tobias

2011-09-01

Full Text Available Abstract Background Piwi-associated RNAs (piRNAs bind transcripts from retrotransposable elements (RTE in mouse germline cells and seemingly act as guides for genomic methylation, thereby repressing the activity of RTEs. It is currently unknown if and how Piwi proteins distinguish RTE transcripts from other cellular RNAs. During germline development, the main target of piRNAs switch between different types of RTEs. Using the piRNA targeting of RTEs as an indicator of RTE activity, and considering the entire population of genomic RTE loci along with their age and location, this study aims at further elucidating the dynamics of RTE activity during mouse germline development. Results Due to the inherent sequence redundancy between RTE loci, assigning piRNA targeting to specific loci is problematic. This limits the analysis, although certain features of piRNA targeting of RTE loci are apparent. As expected, young RTEs display a much higher level of piRNA targeting than old RTEs. Further, irrespective of age, RTE loci near protein-coding coding genes are targeted to a greater extent than RTE loci far from genes. During development, a shift in piRNA targeting is observed, with a clear increase in the relative piRNA targeting of RTEs residing within boundaries of protein-coding gene transcripts. Conclusions Reanalyzing published piRNA sequences and taking into account the features of individual RTE loci provide novel insight into the activity of RTEs during development. The obtained results are consistent with some degree of proportionality between what transcripts become substrates for Piwi protein complexes and the level by which the transcripts are present in the cell. A transition from active transcription of RTEs to passive co-transcription of RTE sequences residing within protein-coding transcripts appears to take place in postnatal development. Hence, the previously reported increase in piRNA targeting of SINEs in postnatal testis development

The small RNA content of human sperm reveals pseudogene-derived piRNAs complementary to protein-coding genes

Science.gov (United States)

Pantano, Lorena; Jodar, Meritxell; Bak, Mads; Ballescà, Josep Lluís; Tommerup, Niels; Oliva, Rafael; Vavouri, Tanya

2015-01-01

At the end of mammalian sperm development, sperm cells expel most of their cytoplasm and dispose of the majority of their RNA. Yet, hundreds of RNA molecules remain in mature sperm. The biological significance of the vast majority of these molecules is unclear. To better understand the processes that generate sperm small RNAs and what roles they may have, we sequenced and characterized the small RNA content of sperm samples from two human fertile individuals. We detected 182 microRNAs, some of which are highly abundant. The most abundant microRNA in sperm is miR-1246 with predicted targets among sperm-specific genes. The most abundant class of small noncoding RNAs in sperm are PIWI-interacting RNAs (piRNAs). Surprisingly, we found that human sperm cells contain piRNAs processed from pseudogenes. Clusters of piRNAs from human testes contain pseudogenes transcribed in the antisense strand and processed into small RNAs. Several human protein-coding genes contain antisense predicted targets of pseudogene-derived piRNAs in the male germline and these piRNAs are still found in mature sperm. Our study provides the most extensive data set and annotation of human sperm small RNAs to date and is a resource for further functional studies on the roles of sperm small RNAs. In addition, we propose that some of the pseudogene-derived human piRNAs may regulate expression of their parent gene in the male germline. PMID:25904136

Conventional Criticism of an Unconventional Text: on Samuel Beckett's Ping Conventional Criticism of an Unconventional Text: on Samuel Beckett's Ping

Directory of Open Access Journals (Sweden)

Maria Helena Peixoto Kopschitz

2008-04-01

Full Text Available Robert Scholes once affirmed that the sense of design is essential to a full reading experience and that in fiction it takes many forms, which are mainly of two kinds: juxtaposition and repetition. I If so one of the very causes of difficulty in "Ping", its repetitive nature and its elusive permutations, can turn into guidelines for its analysis. Beckett's rhetoric of repetition operates as a cumulative process, which allows us to distinguish the fundamental semantic constituents of "Ping". Hence it is possible to try to organize items that correspond to the traditional elements of fiction, as stated below. In order to make the work less hard for the eyes and the mind, I have recopied the seventy sentences of "Ping", each one separately, and numbered them. I shall refer to the numbers in my text. (See Appendix. Robert Scholes once affirmed that the sense of design is essential to a full reading experience and that in fiction it takes many forms, which are mainly of two kinds: juxtaposition and repetition. I If so one of the very causes of difficulty in "Ping", its repetitive nature and its elusive permutations, can turn into guidelines for its analysis. Beckett's rhetoric of repetition operates as a cumulative process, which allows us to distinguish the fundamental semantic constituents of "Ping". Hence it is possible to try to organize items that correspond to the traditional elements of fiction, as stated below. In order to make the work less hard for the eyes and the mind, I have recopied the seventy sentences of "Ping", each one separately, and numbered them. I shall refer to the numbers in my text. (See Appendix.

Calculation of weighted averages approach for the estimation of ping tolerance values

Science.gov (United States)

Silalom, S.; Carter, J.L.; Chantaramongkol, P.

2010-01-01

A biotic index was created and proposed as a tool to assess water quality in the Upper Mae Ping sub-watersheds. The Ping biotic index was calculated by utilizing Ping tolerance values. This paper presents the calculation of Ping tolerance values of the collected macroinvertebrates. Ping tolerance values were estimated by a weighted averages approach based on the abundance of macroinvertebrates and six chemical constituents that include conductivity, dissolved oxygen, biochemical oxygen demand, ammonia nitrogen, nitrate nitrogen and orthophosphate. Ping tolerance values range from 0 to 10. Macroinvertebrates assigned a 0 are very sensitive to organic pollution while macroinvertebrates assigned 10 are highly tolerant to pollution.

Measuring the Digital Divide with PingER

Energy Technology Data Exchange (ETDEWEB)

Cottrell, L.

2003-10-01

We introduce the PingER project/toolkit and show its relevance to monitoring sites in developing countries. We then show results from PingER that illustrate the extent of the Digital Divide in terms of Internet performance between developed and developing regions, which developing regions are catching up, keeping up, or falling behind and the magnitude of the differences in performance between developed regions and developing regions.

Ancient and novel small RNA pathways compensate for the loss of piRNAs in multiple independent nematode lineages.

Directory of Open Access Journals (Sweden)

Peter Sarkies

2015-02-01

Full Text Available Small RNA pathways act at the front line of defence against transposable elements across the Eukaryota. In animals, Piwi interacting small RNAs (piRNAs are a crucial arm of this defence. However, the evolutionary relationships among piRNAs and other small RNA pathways targeting transposable elements are poorly resolved. To address this question we sequenced small RNAs from multiple, diverse nematode species, producing the first phylum-wide analysis of how small RNA pathways evolve. Surprisingly, despite their prominence in Caenorhabditis elegans and closely related nematodes, piRNAs are absent in all other nematode lineages. We found that there are at least two evolutionarily distinct mechanisms that compensate for the absence of piRNAs, both involving RNA-dependent RNA polymerases (RdRPs. Whilst one pathway is unique to nematodes, the second involves Dicer-dependent RNA-directed DNA methylation, hitherto unknown in animals, and bears striking similarity to transposon-control mechanisms in fungi and plants. Our results highlight the rapid, context-dependent evolution of small RNA pathways and suggest piRNAs in animals may have replaced an ancient eukaryotic RNA-dependent RNA polymerase pathway to control transposable elements.

Revisión de registros y notas de Pingüino Rey (Aptenodytes patagonicus) y el Pingüino Penacho Amarillo (Eudyptes chrysocome) en Brasil

OpenAIRE

Barquete, Viviane; Bugoni, Leandro; Silva-Filho, Rodolfo P.; Adornes, Andrea C.

2006-01-01

En este estudio se presenta una revisión de hallazgos previos y nuevos registros del Pingüino Rey (Aptenodytes patagonicus) y del Pingüino Penacho Amarillo (Eudyptes chrysocome) en la costa de Brasil. En total se registraron seis individuos de Pingüino Rey y diez de Pingüino de Penacho Amarillo. Tanto juveniles como adultos de las dos especies fueron encontrados en las playas, especialmente en Rio Grande do Sul, sur de Brasil. Los registros de Pingüino Rey están restringidos al verano, mientr...

Piwi-interacting RNAs (piRNAs) in animals: The story so far

African Journals Online (AJOL)

STORAGESEVER

2009-09-01

Sep 1, 2009 ... germline stem cell maintenance, epigenetic regulation, and transposition. Although the ... Species. MILI. (PIWIL2 In human. Transposon, and piRNA clusters. 24-28 nts .... However, the differences among embryonic, neonatal,.

Division of labor as an emergent phenomenon of social coordination: The example of playing doubles-pong.

Science.gov (United States)

Benerink, Niek H; Zaal, Frank T J M; Casanova, Remy; Bonnardel, Nathalie; Bootsma, Reinoud J

2018-02-01

In many daily situations, our behavior is coordinated with that of others. This study investigated this coordination in a doubles-pong task. In this task, two participants each controlled a paddle that could move laterally near the bottom of a shared computer screen. With their paddles, the players needed to block balls that moved down under an angle. In doing so, they needed to make sure that their paddles did not collide. A successful interception led to the ball bouncing back upwards. Importantly, all communication other than through vision of the shared screen was excluded. In the experiment, the initial position of the paddle of the right player was varied across trials. This allowed testing hypotheses regarding the use of a tacitly understood boundary to divide interception space. This boundary could be halfway the screen, or in the middle between the initial positions of the two paddles. These two hypotheses did not hold. As an alternative to planned division of labor, the behavioral patterns might emerge from continuous visual couplings of paddles and ball. This was tested with an action-based decision model that considered the rates of change of each player's angle between the interception axis and the line connecting the ball and inner edge of the paddle. The model accounted for the observed patterns of behavior to a very large extent. This led to the conclusion that decisions of who would take the ball emerged from ongoing social coordination. Implications for social coordination in general are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Transposable Element Misregulation Is Linked to the Divergence between Parental piRNA Pathways in Drosophila Hybrids.

Science.gov (United States)

Romero-Soriano, Valèria; Modolo, Laurent; Lopez-Maestre, Hélène; Mugat, Bruno; Pessia, Eugénie; Chambeyron, Séverine; Vieira, Cristina; Garcia Guerreiro, Maria Pilar

2017-06-01

Interspecific hybridization is a genomic stress condition that leads to the activation of transposable elements (TEs) in both animals and plants. In hybrids between Drosophila buzzatii and Drosophila koepferae, mobilization of at least 28 TEs has been described. However, the molecular mechanisms underlying this TE release remain poorly understood. To give insight on the causes of this TE activation, we performed a TE transcriptomic analysis in ovaries (notorious for playing a major role in TE silencing) of parental species and their F1 and backcrossed (BC) hybrids. We find that 15.2% and 10.6% of the expressed TEs are deregulated in F1 and BC1 ovaries, respectively, with a bias toward overexpression in both cases. Although differences between parental piRNA (Piwi-interacting RNA) populations explain only partially these results, we demonstrate that piRNA pathway proteins have divergent sequences and are differentially expressed between parental species. Thus, a functional divergence of the piRNA pathway between parental species, together with some differences between their piRNA pools, might be at the origin of hybrid instabilities and ultimately cause TE misregulation in ovaries. These analyses were complemented with the study of F1 testes, where TEs tend to be less expressed than in D. buzzatii. This can be explained by an increase in piRNA production, which probably acts as a defence mechanism against TE instability in the male germline. Hence, we describe a differential impact of interspecific hybridization in testes and ovaries, which reveals that TE expression and regulation are sex-biased. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

FlowPing - The New Tool for Throughput and Stress Testing

Directory of Open Access Journals (Sweden)

Ondrej Vondrous

2015-01-01

Full Text Available This article presents a new tool for network throughput and stress testing. The FlowPing tool is easy to use, and its basic output is very similar to standard Linux ping application. The FlowPing tool is not limited to reach-ability or round trip time testing but is capable of complex UDP based throughput stress testing with rich reporting capabilities on client and server sides. Our new tool implements features, which allow the user to perform tests with variable packet size and traffic rate. All these features can be used in one single test run. This allows the user to use and develop new methodologies for network throughput and stress testing. With the FlowPing tool, it is easy to perform the test with the slowly increasing the amount of network traffic and monitor the behavior of network when the congestion occurs.

The piRNAs forge an immune system for the genome

DEFF Research Database (Denmark)

Muller, Sébastian; Pandey, R.R.; Pillai, R.S.

2013-01-01

Genome integrity of germline is essential for the survival of any species. A dedicated defence mechanism based on small RNA called piRNA (PIWI-interacting RNA) has evolved to protect the germline from the deleterious effects of transposon mobility in genomes such as mutations, deletions or chromo...

The Piwi pathway: from piRNA methylation to histone methylation

NARCIS (Netherlands)

Luteijn, M.J.

2013-01-01

Piwi-interacting RNAs (piRNAs) are germ line-specific small RNA molecules that have a function in genome defense and germ cell development. They associate with a specific class of Argonaute proteins, named Piwi, and function through an RNA interference-like mechanism. These small RNA molecules play

Wrinkling of Pressurized Elastic Shells

KAUST Repository

Vella, Dominic; Ajdari, Amin; Vaziri, Ashkan; Boudaoud, Arezki

2011-01-01

We study the formation of localized structures formed by the point loading of an internally pressurized elastic shell. While unpressurized shells (such as a ping-pong ball) buckle into polygonal structures, we show that pressurized shells

Ping-pong tsherez granitsu, kotoroi net / Aleksandr Shegedin

Index Scriptorium Estoniae

Shegedin, Aleksandr

2006-01-01

Võrus toimus Saksamaa poolel sõdinud veteranide traditsiooniline kokkutulek, kus esines ka peaminister Andrus Ansip. Venemaa reageeris tavapäraste süüdistustega: katse rehabiliteerida natsismi, Teise maailmasõja tulemuste ümberhindamine, venelaste olukord Baltimaades. Venemaa - Soome suhted

Eavesdropping on the "ping-pong" quantum communication protocol

OpenAIRE

Wojcik, Antoni

2002-01-01

The proposed eavesdropping scheme reveals that the quantum communication protocol recently presented by Bostrom and Felbinger [Phys. Rev. Lett. 89, 187902 (2002)] is not secure as far as quantum channel losses are taken into account.

Aubergine and piRNAs promote germline stem cell self-renewal by repressing the proto-oncogene Cbl.

Science.gov (United States)

Rojas-Ríos, Patricia; Chartier, Aymeric; Pierson, Stéphanie; Simonelig, Martine

2017-11-02

PIWI proteins play essential roles in germ cells and stem cell lineages. In Drosophila , Piwi is required in somatic niche cells and germline stem cells (GSCs) to support GSC self-renewal and differentiation. Whether and how other PIWI proteins are involved in GSC biology remains unknown. Here, we show that Aubergine (Aub), another PIWI protein, is intrinsically required in GSCs for their self-renewal and differentiation. Aub needs to be loaded with piRNAs to control GSC self-renewal and acts through direct mRNA regulation. We identify the Cbl proto-oncogene, a regulator of mammalian hematopoietic stem cells, as a novel GSC differentiation factor. Aub stimulates GSC self-renewal by repressing Cbl mRNA translation and does so in part through recruitment of the CCR4-NOT complex. This study reveals the role of piRNAs and PIWI proteins in controlling stem cell homeostasis via translational repression and highlights piRNAs as major post-transcriptional regulators in key developmental decisions. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

Bioassay-guided studies on the cytotoxic and in vitro trypanocidal ...

African Journals Online (AJOL)

This paper reports a bioassay-guided study to search for possible biological activity (cytotoxic and trypanocidal) in two Ugandan medicinal plants. The methodology adopted was the so-called ping-pong approach, involving phytochemical purification (column chromatography and preparative thin layer chromatography), ...

Recursion Versus Replication in Simple Cryptographic Protocols

DEFF Research Database (Denmark)

Hüttel, Hans; Srba, Jiri

2005-01-01

We use some very recent techniques from process algebra to draw interesting conclusions about the well studied class of ping-pong protocols introduced by Dolev and Yao. In particular we show that all nontrivial properties, including reachability and equivalence checking wrt. the whole van Glabbee...

Quantum secure direct communication with high-dimension quantum superdense coding

International Nuclear Information System (INIS)

Wang Chuan; Li Yansong; Liu Xiaoshu; Deng Fuguo; Long Guilu

2005-01-01

A protocol for quantum secure direct communication with quantum superdense coding is proposed. It combines the ideas of block transmission, the ping-pong quantum secure direct communication protocol, and quantum superdense coding. It has the advantage of being secure and of high source capacity

Kinetic study on the enzymatic esterification of octanoic acid and hexanol by immobilized Candida antarctica lipase B

DEFF Research Database (Denmark)

Lopresto, Catia Giovanna; Calabro, Vincenza; Woodley, John M.

2014-01-01

a Ping-Pong bi-bi mechanism with dead-end inhibition by both substrates and, based on the proposed model, the kinetic constants of the esterification reaction are estimated. These parameters are verified to be intrinsic – neither external nor internal mass transfer resistances are significant...

Reexamining the P-Element Invasion of Drosophila melanogaster Through the Lens of piRNA Silencing

Science.gov (United States)

Kelleher, Erin S.

2016-01-01

Transposable elements (TEs) are both important drivers of genome evolution and genetic parasites with potentially dramatic consequences for host fitness. The recent explosion of research on regulatory RNAs reveals that small RNA-mediated silencing is a conserved genetic mechanism through which hosts repress TE activity. The invasion of the Drosophila melanogaster genome by P elements, which happened on a historical timescale, represents an incomparable opportunity to understand how small RNA-mediated silencing of TEs evolves. Repression of P-element transposition emerged almost concurrently with its invasion. Recent studies suggest that this repression is implemented in part, and perhaps predominantly, by the Piwi-interacting RNA (piRNA) pathway, a small RNA-mediated silencing pathway that regulates TE activity in many metazoan germlines. In this review, I consider the P-element invasion from both a molecular and evolutionary genetic perspective, reconciling classic studies of P-element regulation with the new mechanistic framework provided by the piRNA pathway. I further explore the utility of the P-element invasion as an exemplar of the evolution of piRNA-mediated silencing. In light of the highly-conserved role for piRNAs in regulating TEs, discoveries from this system have taxonomically broad implications for the evolution of repression. PMID:27516614

LHC gets the ball rolling

CERN Multimedia

2007-01-01

A technique involving a small ball with a transmitter embedded inside it has been successfully tested in Sector 7-8. The ball is sent through the LHC beam pipes to check the LHC interconnections. The multidisciplinary team responsible for the RF ball project to check the interconnections. From left to right: Rhodri Jones (AB/BI), Eva Calvo (AB/BI), Francesco Bertinelli (AT/MCS), Sonia Bartolome Jimenez (TS/IC), Sylvain Weisz (TS/IC), Paul Cruikshank (AT/VAC), Willemjan Maan (AT/VAC), Alain Poncet (AT/MCS), Marek Gasior (AB/BI). During the tests the ball is inserted very carefully into the vacuum chamber.A game of ping-pong at the LHC? On 13 September a rather unusual test was carried out in Sector 7-8 of the accelerator. A ball just a bit smaller than a ping-pong ball was carefully introduced into one of the accelerator’s two vacuum pipes, where it travelled 800 metres in the space of a few mi...

[Doctor HUANG Shi-ping's acupuncture with golden needles].

Science.gov (United States)

Chen, Teng-Fei; Ma, Zeng-Bin; Xin, Si-Yuan; Zhu, Jiang

2013-08-01

Taking Doctor HUANG Shi-ping as the representative, the school of Huang's golden needle is based on Chinese martial art. Golden needles are adopted as main tool. Attaching great importance on the combination of acupuncture and moxibustioin, it is also characterized with penetrating needling with long needles. Through the development of three generations, it once outshone other schools in the field of acupuncture, and became famous all over the world. It made great contribution to the development of the course of acupuncture. However, with the development of the history, the form of acupuncture education as well as apparatus were all undergone an unified reform. Therefore, Doctor HUANG Shi-ping's acupuncture school be lost gradually.

The Effect of Recreational Activities on Self-Esteem Development of Girls in Adolescence

Science.gov (United States)

Bayazit, Betül

2014-01-01

This study aimed to investigate the effect of recreational activities on self-esteem development of girls in adolescence. For this purpose, a total of 20 girls in adolescence period took part in the present study. Recreational activities program included bowling, patenga, orienteering, basketball, volleyball, badminton, ping-pong, dance, fun…

Structural insights into Rhino-Deadlock complex for germline piRNA cluster specification.

Science.gov (United States)

Yu, Bowen; Lin, Yu An; Parhad, Swapnil S; Jin, Zhaohui; Ma, Jinbiao; Theurkauf, William E; Zhang, Zz Zhao; Huang, Ying

2018-06-01

PIWI-interacting RNAs (piRNAs) silence transposons in germ cells to maintain genome stability and animal fertility. Rhino, a rapidly evolving heterochromatin protein 1 (HP1) family protein, binds Deadlock in a species-specific manner and so defines the piRNA-producing loci in the Drosophila genome. Here, we determine the crystal structures of Rhino-Deadlock complex in Drosophila melanogaster and simulans In both species, one Rhino binds the N-terminal helix-hairpin-helix motif of one Deadlock protein through a novel interface formed by the beta-sheet in the Rhino chromoshadow domain. Disrupting the interface leads to infertility and transposon hyperactivation in flies. Our structural and functional experiments indicate that electrostatic repulsion at the interaction interface causes cross-species incompatibility between the sibling species. By determining the molecular architecture of this piRNA-producing machinery, we discover a novel HP1-partner interacting mode that is crucial to piRNA biogenesis and transposon silencing. We thus explain the cross-species incompatibility of two sibling species at the molecular level. © 2018 The Authors.

The patellar tendon in junior elite volleyball players and an Olympic elite weightlifter

OpenAIRE

Gisslén, Karl

2006-01-01

The principal aim of the present thesis was to prospectively follow (clinical status and ultrasound + Doppler findings) the patellar tendons in the young elite volleyball players at the Swedish National Centre for high school volleyball in Falköping. In an Olympic weightlifter with chronic painful jumper´s knee, the effects of treatment with sclerosing injections followed by early instituted very heavy weightlifting training, was also evaluated. First, in a prevalence study, we demonstrated t...

X Marks the Spot: Creating and Managing a Single Service Point to Improve Customer Service and Maximize Resources

Science.gov (United States)

Venner, Mary Ann; Keshmiripour, Seti

2016-01-01

This article will describe how merging service points in an academic library is an opportunity to improve customer service and utilize staffing resources more efficiently. Combining service points provides libraries with the ability to create a more positive library experience for patrons by minimizing the ping-pong effect for assistance. The…

Academic Value of Non-Academics: The Case for Keeping Extracurriculars

Science.gov (United States)

Kronholz, June

2012-01-01

With school districts struggling to keep their noses above choppy budget waters and voters howling about taxes, should schools be funding Ping-Pong and trading-card clubs? Swim teams, moot court, powder puff football? Latino unions, gay-straight alliances, the Future Business Leaders of America, the French Honors Society, the jazz band, the…

Inhibition of nucleoside diphosphate kinase activity by in vitro phosphorylation by protein kinase CK2. Differential phosphorylation of NDP kinases in HeLa cells in culture

DEFF Research Database (Denmark)

Biondi, R M; Engel, M; Sauane, M

1996-01-01

that in vitro protein kinase CK2 catalyzed phosphorylation of human NDPK A inhibits its enzymatic activity by inhibiting the first step of its ping-pong mechanism of catalysis: its autophosphorylation. Upon in vivo 32P labeling of HeLa cells, we observed that both human NDPKs, A and B, were autophosphorylated...

Recoil Experiments Using a Compressed Air Cannon

Science.gov (United States)

Taylor, Brett

2006-01-01

Ping-Pong vacuum cannons, potato guns, and compressed air cannons are popular and dramatic demonstrations for lecture and lab. Students enjoy them for the spectacle, but they can also be used effectively to teach physics. Recently we have used a student-built compressed air cannon as a laboratory activity to investigate impulse, conservation of…

The second-phase development of the China JinPing underground Laboratory

OpenAIRE

Li, Jainmin; Ji, Xiangdong; Haxton, Wick; Wang, Joseph S. Y.

2014-01-01

During 2013-2015 an expansion of the China JinPing underground Laboratory (CJPL) will be undertaken along a main branch of a bypass tunnel in the JinPing tunnel complex. This second phase of CJPL will increase laboratory space to approximately 96,000 m^3, which can be compared to the existing CJPL-I volume of 4,000 m^3. One design configuration has eight additional hall spaces, each over 60 m long and approximately 12 m in width, with overburdens of about 2.4 km of rock, oriented parallel to ...

Enzymatic synthesis of vitamin B6 precursor

Directory of Open Access Journals (Sweden)

Prlainović Nevena Ž.

2013-01-01

Full Text Available 3-Cyano-4-ethoxymethyl-6-methyl-2-pyridone is an important precursor in the synthesis of vitamin B6, obtained in the addition reaction between 2-cyanoacetamide and 1-ethoxy-2,4-pentanedione catalyzed by lipase from Candida rugosa (triacylglycerol ester hydrolases, EC 3.1.1.3. This work shows new experimental data and mathematical modeling of lipase catalyzed synthesis of 3-cyano-4-ethoxymethyl-6-methyl-2-pyridone, starting from 1-ethoxy-2,4-pentanedione and 2-cyanoacetamide. Kinetic measurements were done at 50 oC with enzyme concentration of 1.2 % w/v. Experimental results were fitted with two kinetic models: the ordered bi-ter and ping-pong bi-ter model, and the initial rates of the reaction were found to correlate best with a ping-pong bi-ter mechanism with inhibition by 2-cyanoacetamide. Obtained specificity constants indicated that lipase from C. rugosa had higher affinity towards 1-ethoxy-2,4-pentanedione and less bulky substrates. [Projekat Ministarstva nauke Republike Srbije, br. 172013, br. III 46010 and br. 172049

Altered expression of testis-specific genes, piRNAs, and transposons in the silkworm ovary masculinized by a W chromosome mutation

Science.gov (United States)

2012-01-01

Background In the silkworm, Bombyx mori, femaleness is strongly controlled by the female-specific W chromosome. Originally, it was presumed that the W chromosome encodes female-determining gene(s), accordingly called Fem. However, to date, neither Fem nor any protein-coding gene has been identified from the W chromosome. Instead, the W chromosome is occupied with numerous transposon-related sequences. Interestingly, the silkworm W chromosome is a source of female-enriched PIWI-interacting RNAs (piRNAs). piRNAs are small RNAs of 23-30 nucleotides in length, which are required for controlling transposon activity in animal gonads. A recent study has identified a novel mutant silkworm line called KG, whose mutation in the W chromosome causes severe female masculinization. However, the molecular nature of KG line has not been well characterized yet. Results Here we molecularly characterize the KG line. Genomic PCR analyses using currently available W chromosome-specific PCR markers indicated that no large deletion existed in the KG W chromosome. Genetic analyses demonstrated that sib-crosses within the KG line suppressed masculinization. Masculinization reactivated when crossing KG females with wild type males. Importantly, the KG ovaries exhibited a significantly abnormal transcriptome. First, the KG ovaries misexpressed testis-specific genes. Second, a set of female-enriched piRNAs was downregulated in the KG ovaries. Third, several transposons were overexpressed in the KG ovaries. Conclusions Collectively, the mutation in the KG W chromosome causes broadly altered expression of testis-specific genes, piRNAs, and transposons. To our knowledge, this is the first study that describes a W chromosome mutant with such an intriguing phenotype. PMID:22452797

Siim Nestor soovitab : Eddie Henderson. Pong. Tony Touch. Teenage Kicks / Siim Nestor

Index Scriptorium Estoniae

Nestor, Siim, 1974-

2005-01-01

Ameerika trompetisti Eddie Hendersoni ja briti nu-jazz-bändi Mr. Gone'i kontserdist Jazzkaare raames 27. jaan. klubis Rock Café. Saksa rockansambli Mürgelmaschine kontserdist 28. jaan üritusel Pong. Ameerika hip-hop -diskor ja produtsent Tony Touch klubis Privé 28. jaan.. Üritusel Teenage Kicks 29. jaan. esinevad saksa ansambel Kante, rootsi ansambel Sons Of Cyrus, ansamblid Shelton San ja Kwing-Kungks

Tricky Circuitry

Science.gov (United States)

Davies, Tony

2014-01-01

Teaching children about circuits and the way electricity works is a "tricky business" because it is invisible. Just imagine all eyes are on the teacher as he or she produces for the class what looks like a ping-pong ball and then, with a wave of their hand, the incredible happens! This wonderful white sphere begins to glow red and a…

The French Reader's Relationship to Poetry in the Electronic Age: Ponge, Alferi, and Vassiliou

Science.gov (United States)

LeBlond-Schrader, Ellen Benton

2010-01-01

My dissertation investigates the twentieth and twenty-first century reader's relationship to poetic text as it is altered through daily exposure to technology in the rise of the information age, as seen in the works of Francis Ponge, Pierre Alferi and Veronique Vassiliou. My project also examines historical documents--radio and television…

Playback system designed for X-Band SAR

International Nuclear Information System (INIS)

Yuquan, Liu; Changyong, Dou

2014-01-01

SAR(Synthetic Aperture Radar) has extensive application because it is daylight and weather independent. In particular, X-Band SAR strip map, designed by Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, provides high ground resolution images, at the same time it has a large spatial coverage and a short acquisition time, so it is promising in multi-applications. When sudden disaster comes, the emergency situation acquires radar signal data and image as soon as possible, in order to take action to reduce loss and save lives in the first time. This paper summarizes a type of X-Band SAR playback processing system designed for disaster response and scientific needs. It describes SAR data workflow includes the payload data transmission and reception process. Playback processing system completes signal analysis on the original data, providing SAR level 0 products and quick image. Gigabit network promises radar signal transmission efficiency from recorder to calculation unit. Multi-thread parallel computing and ping pong operation can ensure computation speed. Through gigabit network, multi-thread parallel computing and ping pong operation, high speed data transmission and processing meet the SAR radar data playback real time requirement

Playback system designed for X-Band SAR

Science.gov (United States)

Yuquan, Liu; Changyong, Dou

2014-03-01

SAR(Synthetic Aperture Radar) has extensive application because it is daylight and weather independent. In particular, X-Band SAR strip map, designed by Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, provides high ground resolution images, at the same time it has a large spatial coverage and a short acquisition time, so it is promising in multi-applications. When sudden disaster comes, the emergency situation acquires radar signal data and image as soon as possible, in order to take action to reduce loss and save lives in the first time. This paper summarizes a type of X-Band SAR playback processing system designed for disaster response and scientific needs. It describes SAR data workflow includes the payload data transmission and reception process. Playback processing system completes signal analysis on the original data, providing SAR level 0 products and quick image. Gigabit network promises radar signal transmission efficiency from recorder to calculation unit. Multi-thread parallel computing and ping pong operation can ensure computation speed. Through gigabit network, multi-thread parallel computing and ping pong operation, high speed data transmission and processing meet the SAR radar data playback real time requirement.

Adaptación de parámetros de handover para reducir transferencias de conexión erróneas en redes inalámbricas heterogéneas de nueva generación

Directory of Open Access Journals (Sweden)

Enrique René Bastidas Puga

2015-01-01

Full Text Available Un objetivo de los sistemas de comunicación móvil de Quinta Generación (5G, es atender el creciente volumen de usuarios y el tráfico de datos. El despliegue de redes heterogéneas (HetNet es una opción que incrementa la capacidad de estos sistemas, pero también la cantidad de procesos de transferencia de servicio ( handover y, con ello, el número de fallas de handover y de handovers ping-pong . Para reducir estas fallas, que deterioran la calidad de servicio de la HetNet, en este trabajo se propone adaptar los parámetros que disparan un handover , tiempo-para-disparo ( TTT y margen-de- handover ( HOM , en función de la relación señal-ruido-interferencia ( SINR . Evaluaciones numéricas muestran que las tasas de fallas de handover y de handovers ping-pong se reducen simultáneamente al adaptar el TTT y HOM con un conocimiento perfecto de valores futuros de SINR , contrario al caso cuando se mantienen constantes, en el que se presenta un compro - miso entre ambas fallas.

Deterministic Secure Direct Communication Using Mixed state

OpenAIRE

Cai, Qing-yu

2003-01-01

We show an improved ping-pong protocol which is based on the protocol showed by Kim Bostrom and Timo Felbinger [Phys. Rev. Lett. 89, 187902 (2002); quant-ph/0209040]. We show that our protocol is asymptotically secure key distribution and quasisecure direct communication using a single photon resource. And this protocol can be can be carried out with great efficiency and speed using today's technology.

Final design proposal: Delta Group-Nood Rider 821(tm)

Science.gov (United States)

Pastega, C. B.; Vahey, B. P.; Hoffman, K. W.; Doherty, M. C.; Fay, M. J.; Konesky, A. L.; Lilly, D. C.; Moody, D. J.

1991-01-01

The Nood Rider 821 (trademark) twin-engine, prop passenger aircraft is described. It is argued that the aircraft is very economical to operate and maintain, offering competitive advantages in the air travel marketplace. The aircraft was designed to operate in 'Aeroworld', a fictional world where the passengers are ping pong balls and the distances between cites are on the order of thousands of feet.

Exploitation of Microdoppler and Multiple Scattering Phenomena for Radar Target Recognition

Science.gov (United States)

2006-08-24

progress on the reserach grant "Exploitation of MicroDoppler and Multiple Scattering Phenomena for Radar Target Recognition" during the period 1...paper describes a methodology of modeling A number of ray-based EM techniques have been interferometric synthetic aperture radar (IFSAR) images...modes including the single present an IFSAR simulation methodology to simulate the antenna transmit mode, the ping-pong mode or the repeat interferogram

Roles of piRNAs in microcystin-leucine-arginine (MC-LR) induced reproductive toxicity in testis on male offspring.

Science.gov (United States)

Zhang, Ling; Zhang, Hui; Zhang, Huan; Benson, Mikael; Han, Xiaodong; Li, Dongmei

2017-07-01

In the present study, we evaluated the toxic effects on the testis of the male offspring of MC-LR exposure during fetal and lactational periods. Pregnant females were distributed into two experimental groups: control group and MC-LR group which were exposed to 0 and 10 μg/L of MC-LR, respectively, through drinking water separately during fetal and lactational periods. At the age of 30 days after birth, the male offspring were euthanized. The body weight, testis index, and histomorphology change were observed and the global changes of piwi-interacting RNA (piRNA) expression were evaluated. The results revealed that MC-LR was found in the testis of male offspring, body weight and testis index decreased significantly, and testicular tissue structure was damaged in the MC-LR group. In addition, the exposure to MC-LR resulted in an altered piRNA expression profile and an increase of the cell apoptosis and a decrease of the cell proliferation in the testis of the male offspring. It was reasonable to speculate that the toxic effects on reproductive system of the male offspring in MC-LR group might be mediated by piRNAs through the regulation of the target genes. As far as we are aware, this is the first report showing that MC-LR could play a role in disorder of proliferative and cell apoptosis in the testis of the male offspring by the maternal transmission effect of toxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Local community participatory learning with a nature interpretation system: A case study in Ban Pong, Sansai district, Chiang Mai, Thailand

Directory of Open Access Journals (Sweden)

Raktida Siri

2017-05-01

The research employed multiple research methods consisting of surveys, focus group discussion, and participatory observation. Samples used in the study were members of the Agro-tourism Club of Ban Pong community, Ban Pong, Papai sub-district, Sansai district, Chiang Mai province. The community members undertook learning through a four-step participatory learning process; (1 analyzing problems, (2 planning, exploring, and voting, (3 implementation, and (4 evaluation. The results showed that the community members had gained knowledge about tourism interpretation and showed a positive attitude toward the development of tourism interpretation. Moreover, at the end of the study, they had actually developed an interpretative nature trail that was derived from the real needs of their community.

Loss-of-function of a ubiquitin-related modifier promotes the mobilization of the active MITE mPing.

Science.gov (United States)

Tsukiyama, Takuji; Teramoto, Shota; Yasuda, Kanako; Horibata, Akira; Mori, Nanako; Okumoto, Yutaka; Teraishi, Masayoshi; Saito, Hiroki; Onishi, Akiko; Tamura, Kanako; Tanisaka, Takatoshi

2013-05-01

Miniature inverted-repeat transposable elements (MITEs) are widespread in both prokaryotic and eukaryotic genomes, where their copy numbers can attain several thousands. Little is known, however, about the genetic factor(s) affecting their transpositions. Here, we show that disruption of a gene encoding ubiquitin-like protein markedly enhances the transposition activity of a MITE mPing in intact rice plants without any exogenous stresses. We found that the transposition activity of mPing is far higher in the lines harboring a non-functional allele at the Rurm1 (Rice ubiquitin-related modifier-1) locus than in the wild-type line. Although the alteration of cytosine methylation pattern triggers the activation of transposable elements under exogenous stress conditions, the methylation degrees in the whole genome, the mPing-body region, and the mPing-flanking regions of the non-functional Rurm1 line were unchanged. This study provides experimental evidence for one of the models of genome shock theory that genetic accidents within cells enhance the transposition activities of transposable elements.

Recursion vs. Replication in Simple Cryptographic Protocols

DEFF Research Database (Denmark)

Huttel, Hans; Srba, Jiri

2005-01-01

We use some recent techniques from process algebra to draw several conclusions about the well studied class of ping-pong protocols introduced by Dolev and Yao. In particular we show that all nontrivial properties, including reachability and equivalence checking wrt. the whole van Glabbeek's spect...... of messages in the sense of Amadio, Lugiez and Vanackere. We conclude by showing that reachability analysis for a replicative variant of the protocol becomes decidable....

Dihydrooxonate is a substrate of Dihydroorrotate Dehydrogenase (DHOD) providing evidence for involvement of crsteine and serine residues in base catalysis

DEFF Research Database (Denmark)

Björnberg, Olof; Jordan, Douglas B.; Palfey, Bruce Allan

2001-01-01

pKa of the 5-position in the substrate. Oxonate, the oxidation product of dihydrooxonate, was a competitive inhibitor versus dihydroorotate, and DHODA was the most sensitive of the three enzymes. DHODA was reinvestigated with respect to product inhibition by orotate. The results suggest a classical...... one-site ping-pong mechanism with fumarate as electron acceptor, while the kinetics with ferricyanide is highly dependent on the detailed reaction conditions....

PIN-G – A novel reporter for imaging and defining the effects of trafficking signals in membrane proteins

Directory of Open Access Journals (Sweden)

Hu Weiwen

2006-03-01

Full Text Available Abstract Background The identification of protein trafficking signals, and their interacting mechanisms, is a fundamental objective of modern biology. Unfortunately, the analysis of trafficking signals is complicated by their topography, hierarchical nature and regulation. Powerful strategies to test candidate motifs include their ability to direct simpler reporter proteins, to which they are fused, to the appropriate cellular compartment. However, present reporters are limited by their endogenous expression, paucity of cloning sites, and difficult detection in live cells. Results Consequently, we have engineered a mammalian expression vector encoding a novel trafficking reporter – pIN-G – consisting of a simple, type I integral protein bearing permissive intra/extracellular cloning sites, green fluorescent protein (GFP, cMyc and HA epitope tags. Fluorescence imaging, flow cytometry and biochemical assays of transfected HEK293 cells, confirm the size, topology and surface expression of PIN-G. Moreover, a pIN-G fusion construct, containing a Trans-Golgi Network (TGN targeting determinant, internalises rapidly from the cell surface and localises to the TGN. Additionally, another PIN-G fusion protein and its mutants reveal trafficking determinants in the cytoplasmic carboxy terminus of Kv1.4 voltage-gated potassium channels. Conclusion Together, these data indicate that pIN-G is a versatile, powerful, new reporter for analysing signals controlling membrane protein trafficking, surface expression and dynamics.

Decentralized Cooperation Strategies in Two-Dimensional Traffic of Cellular Automata

International Nuclear Information System (INIS)

Fang Jun; Qin Zheng; Xu Zhaohui; Chen Xiqun; Leng Biao; Jiang Zineng

2012-01-01

We study the two-dimensional traffic of cellular automata using computer simulation. We propose two type of decentralized cooperation strategies, which are called stepping aside (CS-SA) and choosing alternative routes (CS-CAR) respectively. We introduce them into an existing two-dimensional cellular automata (CA) model. CS-SA is designed to prohibit a kind of ping-pong jump when two objects standing together try to move in opposite directions. CS-CAR is designed to change the solution of conflict in parallel update. CS-CAR encourages the objects involved in parallel conflicts choose their alternative routes instead of waiting. We also combine the two cooperation strategies (CS-SA-CAR) to test their combined effects. It is found that the system keeps on a partial jam phase with nonzero velocity and flow until the density reaches one. The ratios of the ping-pong jump and the waiting objects involved in conflict are decreased obviously, especially at the free phase. And the average flow is improved by the three cooperation strategies. Although the average travel time is lengthened a bit by CS-CAR, it is shorten by CS-SA and CS-SA-CAR. In addition, we discuss the advantage and applicability of decentralized cooperation modeling.

Modeling the methanolysis of triglyceride catalyzed by immobilized lipase in a continuous-flow packed-bed reactor

International Nuclear Information System (INIS)

Tran, Dang-Thuan; Lin, Yi-Jan; Chen, Ching-Lung; Chang, Jo-Shu

2014-01-01

Highlights: • A Burkholderia lipase was immobilized on alkyl-grafted celite carriers. • Celite-alkyl-lipase catalyzed the methanolysis of triglyceride in packed-bed reactor. • The kinetics of the enzymatic transesterification follows Ping Pong Bi Bi mechanism. • Models were developed to discuss the mass transfer and enzyme kinetics in the PBR. - Abstract: A Burkholderia lipase was immobilized on celite grafted with long alkyl groups. The immobilized lipase-catalyzed methanolysis of sunflower oil in a packed-bed reactor (PBR) follows the Ping Pong Bi Bi mechanism. The external mass transfer and enzymatic reaction that simultaneously occurred in the PBR were investigated via the mathematical models. The overall biodiesel production in the PBR was verified to work in an enzymatic reaction-limited regime. Triglyceride conversion and biodiesel yield were higher under a lower reactant feeding rate, while a larger amount of biocatalyst would be required to achieve the designated conversion rate if a higher reactant feeding rate was employed. The PBR can achieve nearly complete conversion of triglyceride at a biocatalyst bed height of 60 cm (ca. 29 g biocatalyst) and a flow rate of 0.1 ml min −1 , whereas the biodiesel yield was lower than 67%, probably due to the positional specificity of Burkholderia lipase and the accumulation of glycerol

On the implementation of a deterministic secure coding protocol using polarization entangled photons

OpenAIRE

Ostermeyer, Martin; Walenta, Nino

2007-01-01

We demonstrate a prototype-implementation of deterministic information encoding for quantum key distribution (QKD) following the ping-pong coding protocol [K. Bostroem, T. Felbinger, Phys. Rev. Lett. 89 (2002) 187902-1]. Due to the deterministic nature of this protocol the need for post-processing the key is distinctly reduced compared to non-deterministic protocols. In the course of our implementation we analyze the practicability of the protocol and discuss some security aspects of informat...

La physique à l'honneur Le CERN, l'ESA et l'ESO mettent la physique en scène

CERN Multimedia

CERN Press Office. Geneva

2000-01-01

Can you imagine how much physics is in a simple match of ping-pong, in throwing a boomerang, or in a musical concert? Physics is all around us and governs our lives. The World-Wide Web and mobile communication are only two examples of technologies that have rapidly found their way from science into the everyday life. But who is going to maintain these technologies and develop new ones in the future?

Substrate Trapping in Crystals of the Thiolase OleA Identifies Three Channels That Enable Long Chain Olefin Biosynthesis*

OpenAIRE

Goblirsch, Brandon R.; Jensen, Matthew R.; Mohamed, Fatuma A.; Wackett, Lawrence P.; Wilmot, Carrie M.

2016-01-01

Phylogenetically diverse microbes that produce long chain, olefinic hydrocarbons have received much attention as possible sources of renewable energy biocatalysts. One enzyme that is critical for this process is OleA, a thiolase superfamily enzyme that condenses two fatty acyl-CoA substrates to produce a β-ketoacid product and initiates the biosynthesis of long chain olefins in bacteria. Thiolases typically utilize a ping-pong mechanism centered on an active site cysteine residue. Reaction wi...

Xiao-Ai-Ping, a TCM Injection, Enhances the Antigrowth Effects of Cisplatin on Lewis Lung Cancer Cells through Promoting the Infiltration and Function of CD8+ T Lymphocytes

Directory of Open Access Journals (Sweden)

Wanshuai Li

2013-01-01

Full Text Available Objectives. To investigate how Xiao-Ai-Ping injection, a traditional Chinese medicine and an ancillary drug in tumor treatment, enhances the antitumor effects of cisplatin on Lewis lung cancer (LLC cells. Methods. LLC-bearing mice were daily intraperitoneally injected with various doses of cisplatin, Xiao-Ai-Ping, or cisplatin plus Xiao-Ai-Ping, respectively. Body weight and tumor volumes were measured every three days. Results. Combination of Xiao-Ai-Ping and cisplatin yielded significantly better antigrowth and proapoptotic effects on LLC xenografts than sole drug treatment did. In addition, we found that Xiao-Ai-Ping triggered the infiltration of CD8+ T cells, a group of cytotoxic T cells, to LLC xenografts. Furthermore, the mRNA levels of interferon-γ (ifn-γ, perforin-1 (prf-1, and granzyme B (gzmb in CD8+ T cells were significantly increased after combination treatment of Xiao-Ai-Ping and cisplatin. In vitro studies showed that Xiao-Ai-Ping markedly upregulated the mRNA levels of ifn-γ, prf-1, and gzmb in CD8+ T cells in a concentration-dependent manner, suggesting that Xiao-Ai-Ping augments the function of CD8+ T cells. Conclusions. Xiao-Ai-Ping promotes the infiltration and function of CD8+ T cells and thus enhances the antigrowth effects of cisplatin on LLC xenografts, which provides new evidence for the combination of Xiao-Ai-Ping and cisplatin in clinic in China.

Small RNA Profiling in Dengue Virus 2-Infected Aedes Mosquito Cells Reveals Viral piRNAs and Novel Host miRNAs

NARCIS (Netherlands)

Miesen, P.; Ivens, A.; Buck, A.H.; Rij, R.P. van

2016-01-01

In Aedes mosquitoes, infections with arthropod-borne viruses (arboviruses) trigger or modulate the expression of various classes of viral and host-derived small RNAs, including small interfering RNAs (siRNAs), PIWI interacting RNAs (piRNAs), and microRNAs (miRNAs). Viral siRNAs are at the core of

Creating Accessible Science Museums with User-Activated Environmental Audio Beacons (Ping!)

Science.gov (United States)

Landau, Steven; Wiener, William; Naghshineh, Koorosh; Giusti, Ellen

2005-01-01

In 2003, Touch Graphics Company carried out research on a new invention that promises to improve accessibility to science museums for visitors who are visually impaired. The system, nicknamed Ping!, allows users to navigate an exhibit area, listen to audio descriptions, and interact with exhibits using a cell phone-based interface. The system…

Report on Third International Intensive Aftercare Conference in Norrköping, Sweden

DEFF Research Database (Denmark)

Jones, Christina; Bäckman, Carl; Egerod, Ingrid

2015-01-01

The third international conference on intensive care unit (ICU) diaries and intensive aftercare took place in Norrköping, Sweden, on 28 November 2013. The conference was organized by Carl Bäckman and colleagues, Vrinnevi Hospital and NOFI, and represented by Sissell Storli. More than 100 clinicians...

THE “HAPPY BOUNCING BALL” GAME FOR THE LEARNING OF TABLE TENNIS FOR GRADE V PRIMARY SCHOOL STUDENTS "PERMAINAN “HAPPY BOUNCING BALL” UNTUK PEMBELAJARAN TENIS MEJA BAGI SISWA KELAS V SEKOLAH DASAR"

Directory of Open Access Journals (Sweden)

Moch Fahmi Abdulaziz

2017-06-01

Full Text Available Physical education, health and sports is an integral part of the overall education, aiming to develop physical fitness, skills of motion, critical thinking skills, social skills, reasoning, emotional stability, moral action, aspects of healthy living patterns and the introduction of clean environment through physical activity, sport and health selected planned systematically in order to achieve the goals of national education. Physical education, health and sports are the attempts to embody the whole person in the school, either from a basic to intermediate education level.Table tennis is one of the Physical education learning material taught in elementary school. However, the reality in the learning process has not been implemented optimally because the table was not proportional to the number of students. Thus the need to win and the modifications to the game, make students more actively in learning. The problems that plagued the school made teacher’s creativity in developing models of learning a new, yet fun and in accordance with the objectives of the learning that has been set. Modification of the learning game of ping-pong was one of the efforts that must be realized. Learning the ping-pong game through the happy bouncing ball game was expected to make children more actively engaged in a variety of pleasant situations and conditions, while following the learning of table tennis game.

The Intercomparison of X-Band SAR Images from COSMO‑SkyMed and TerraSAR-X Satellites: Case Studies

Directory of Open Access Journals (Sweden)

Simone Pettinato

2013-06-01

Full Text Available The analysis of experimental data collected by X-band SAR of COSMO-SkyMed (CSK® and TerraSAR-X (TSX images on the same surface types has shown significant differences in the signal level of the two sensors. In order to investigate the possibility of combining data from the two instruments, a study was carried out by comparing images collected with similar orbital and sensor parameters (e.g., incidence angle, polarization, look angle at approximately the same date on two Italian agricultural test sites. Several homogenous agricultural fields within the observed area common to the two sensors were selected. Some forest plots have also been considered and used as a reference target. Direct comparisons were then performed between CSK and TSX images in different acquisition modes. The analysis carried out on the agricultural fields showed that, in general, the backscattering coefficient is higher in TSX Stripmap images with respect to CSK-Himage (about 3 dB, while CSK-Ping Pong data showed values lower than TSX of about 4.8 dB. Finally, a difference in backscattering of about 2.5 dB was pointed out between CSK-Himage and Ping-Pong images on agricultural fields. These results, achieved on bare soils, have also been compared with simulations performed by using the Advanced Integral Equation Model (AIEM.

Small RNA Profiling in Dengue Virus 2-Infected Aedes Mosquito Cells Reveals Viral piRNAs and Novel Host miRNAs.

Science.gov (United States)

Miesen, Pascal; Ivens, Alasdair; Buck, Amy H; van Rij, Ronald P

2016-02-01

In Aedes mosquitoes, infections with arthropod-borne viruses (arboviruses) trigger or modulate the expression of various classes of viral and host-derived small RNAs, including small interfering RNAs (siRNAs), PIWI interacting RNAs (piRNAs), and microRNAs (miRNAs). Viral siRNAs are at the core of the antiviral RNA interference machinery, one of the key pathways that limit virus replication in invertebrates. Besides siRNAs, Aedes mosquitoes and cells derived from these insects produce arbovirus-derived piRNAs, the best studied examples being viruses from the Togaviridae or Bunyaviridae families. Host miRNAs modulate the expression of a large number of genes and their levels may change in response to viral infections. In addition, some viruses, mostly with a DNA genome, express their own miRNAs to regulate host and viral gene expression. Here, we perform a comprehensive analysis of both viral and host-derived small RNAs in Aedes aegypti Aag2 cells infected with dengue virus 2 (DENV), a member of the Flaviviridae family. Aag2 cells are competent in producing all three types of small RNAs and provide a powerful tool to explore the crosstalk between arboviral infection and the distinct RNA silencing pathways. Interestingly, besides the well-characterized DENV-derived siRNAs, a specific population of viral piRNAs was identified in infected Aag2 cells. Knockdown of Piwi5, Ago3 and, to a lesser extent, Piwi6 results in reduction of vpiRNA levels, providing the first genetic evidence that Aedes PIWI proteins produce DENV-derived small RNAs. In contrast, we do not find convincing evidence for the production of virus-derived miRNAs. Neither do we find that host miRNA expression is strongly changed upon DENV2 infection. Finally, our deep-sequencing analyses detect 30 novel Aedes miRNAs, complementing the repertoire of regulatory small RNAs in this important vector species.

Design and realization of real-time processing system for seismic exploration

International Nuclear Information System (INIS)

Zhang Sifeng; Cao Ping; Song Kezhu; Yao Lin

2010-01-01

For solving real-time seismic data processing problems, a high-speed, large-capacity and real-time data processing system is designed based on FPGA and ARM. With the advantages of multi-processor, DRPS has the characteristics of high-speed data receiving, large-capacity data storage, protocol analysis, data splicing, data converting from time sequence into channel sequence, no dead time data ping-pong storage, etc. And with the embedded Linux operating system, DRPS has the characteristics of flexibility and reliability. (authors)

Monotonic Set-Extended Prefix Rewriting and Verification of Recursive Ping-Pong Protocols

DEFF Research Database (Denmark)

Delzanno, Giorgio; Esparza, Javier; Srba, Jiri

2006-01-01

of messages) some verification problems become decidable. In particular we give an algorithm to decide control state reachability, a problem related to security properties like secrecy and authenticity. The proof is via a reduction to a new prefix rewriting model called Monotonic Set-extended Prefix rewriting...

MicroRNA and piRNA profiles in normal human testis detected by next generation sequencing.

Directory of Open Access Journals (Sweden)

Qingling Yang

Full Text Available BACKGROUND: MicroRNAs (miRNAs are the class of small endogenous RNAs that play an important regulatory role in cells by negatively affecting gene expression at transcriptional and post-transcriptional levels. There have been extensive studies aiming to discover miRNAs and to analyze their functions in the cells from a variety of species. However, there are no published studies of miRNA profiles in human testis using next generation sequencing (NGS technology. RESULTS: We employed Solexa sequencing technology to profile miRNAs in normal human testis. Total 770 known and 5 novel human miRNAs, and 20121 piRNAs were detected, indicating that the human testis has a complex population of small RNAs. The expression of 15 known and 5 novel detected miRNAs was validated by qRT-PCR. We have also predicted the potential target genes of the abundant known and novel miRNAs, and subjected them to GO and pathway analysis, revealing the involvement of miRNAs in many important biological phenomenon including meiosis and p53-related pathways that are implicated in the regulation of spermatogenesis. CONCLUSIONS: This study reports the first genome-wide miRNA profiles in human testis using a NGS approach. The presence of large number of miRNAs and the nature of their target genes suggested that miRNAs play important roles in spermatogenesis. Here we provide a useful resource for further elucidation of the regulatory role of miRNAs and piRNAs in the spermatogenesis. It may also facilitate the development of prophylactic strategies for male infertility.

Effects of the Environment Temperature on the Characteristic of Parallax Ping Ultrasonic Sensor

Directory of Open Access Journals (Sweden)

Tony Stănescu

2014-12-01

Full Text Available This paper presents some characteristics of the Parallax PING ultrasonic sensor and the way the environmental temperature affects them. The used sensor functions at 40 KHz. There is also presented the experimental test setup and the authors’ conclusions on the functioning of the sensor at various temperatures.

PingER: Internet performance monitoring -- How do collisions make better physics

International Nuclear Information System (INIS)

Matthews, W.

2000-01-01

Internet connectivity is critical infrastructure for modern high energy nuclear and particle physics experiments at laboratories around the world. Achieving the ambitious computing goals is dependent on reliable and fast connections between collaborators in geographically separate regions. The ambitious computing goals of experiments such as BaBar, RHIC and the LHC place internet connectivity in a highly critical position. More over the ability to monitor performance and identify weak points for upgrades has become pivotal to recruiting collaborators not only overseas from the location of the experiment but in locations previously considered remote. The methodology of the Internet End-to-End Performance Monitoring (IEPM) project and long-term trends in regional and trans-oceanic performance measured by the PingER tools has previously been described. The project has grown significantly and now 593 nodes at 424 sites in 72 countries are monitored by 28 monitoring sites in 15 countries. A total of 2,138 end-to-end pairs are monitored, making PingER probably the largest performance monitoring project in the world. Recently particular effort has been made to extend the monitoring of locations in East Europe and the former USSR and to Central and South America and the Middle East, reflecting the increasing reach of high energy nuclear and particle physics research

Improving the capacity of the Boström-Felbinger protocol

Science.gov (United States)

Cai, Qing-Yu; Li, Bai-Wen

2004-05-01

We show that the capacity of the Boström-Felbinger (ping-pong) protocol [Phys. Rev. Lett. 89, 187902 (2002)] can be doubled by introducing two additional unitary operations. In message mode, Alice can use one of the four unitary operations to encode two classical bits of information. Bob can decode Alice’s information by using a Bell-basis measurement. Security against eavesdropping attack can be ensured by using two conjugate measurement bases in control mode. A message authentification method can protect this communication against a man-in-the-middle attack without eavesdropping.

One Step Quantum Key Distribution Based on EPR Entanglement.

Science.gov (United States)

Li, Jian; Li, Na; Li, Lei-Lei; Wang, Tao

2016-06-30

A novel quantum key distribution protocol is presented, based on entanglement and dense coding and allowing asymptotically secure key distribution. Considering the storage time limit of quantum bits, a grouping quantum key distribution protocol is proposed, which overcomes the vulnerability of first protocol and improves the maneuverability. Moreover, a security analysis is given and a simple type of eavesdropper's attack would introduce at least an error rate of 46.875%. Compared with the "Ping-pong" protocol involving two steps, the proposed protocol does not need to store the qubit and only involves one step.

Improving the capacity of the Bostroem-Felbinger protocol

International Nuclear Information System (INIS)

Cai Qingyu; Li Baiwen

2004-01-01

We show that the capacity of the Bostroem-Felbinger (ping-pong) protocol [Phys. Rev. Lett. 89, 187902 (2002)] can be doubled by introducing two additional unitary operations. In message mode, Alice can use one of the four unitary operations to encode two classical bits of information. Bob can decode Alice's information by using a Bell-basis measurement. Security against eavesdropping attack can be ensured by using two conjugate measurement bases in control mode. A message authentification method can protect this communication against a man-in-the-middle attack without eavesdropping

Eavesdropping on the two-way quantum communication protocols with invisible photons

Energy Technology Data Exchange (ETDEWEB)

Cai Qingyu [State Key Laboratory of Magnetics Resonance and Atomic and Molecular Physics, Wuhan Institution of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)]. E-mail: qycai@wipm.ac.cn

2006-02-20

The crucial issue of quantum communication protocol is its security. In this Letter, we show that all the deterministic and direct two-way quantum communication protocols, sometimes called ping-pong (PP) protocols, are insecure when an eavesdropper uses the invisible photon to eavesdrop on the communication. With our invisible photon eavesdropping (IPE) scheme, the eavesdropper can obtain full information of the communication with zero risk of being detected. We show that this IPE scheme can be implemented experimentally with current technology. Finally, a possible improvement of PP communication protocols security is proposed00.

SP.ACE: taking secondary school students' hearts and minds "up, up and away"

Science.gov (United States)

de Schrijver, Erik

2005-08-01

Secondary school students were given the opportunity to build and fly "pongsats" (small experiments weighing under 100 grams each, and packed inside a ping pong ball) on high-altitude balloons bound for 100000 feet, or 30 km: the edge of space. The need to acquire the knowledge and know-how to build successful experiments gave birth to the SP.ACE project. Over their last 3 years of secondary education, students are now learning about flight vehicles, the physical conditions in space, microcontrollers, sensors, programming, data logging, flight path analysis, and much more.

Eavesdropping on the two-way quantum communication protocols with invisible photons

International Nuclear Information System (INIS)

Cai Qingyu

2006-01-01

The crucial issue of quantum communication protocol is its security. In this Letter, we show that all the deterministic and direct two-way quantum communication protocols, sometimes called ping-pong (PP) protocols, are insecure when an eavesdropper uses the invisible photon to eavesdrop on the communication. With our invisible photon eavesdropping (IPE) scheme, the eavesdropper can obtain full information of the communication with zero risk of being detected. We show that this IPE scheme can be implemented experimentally with current technology. Finally, a possible improvement of PP communication protocols security is proposed

Using magnets in physical blocks that behave as programming objects

CSIR Research Space (South Africa)

Smith, Andrew C

2007-02-01

Full Text Available with the concepts. Children in the age group 4-7 years sometimes have difficulty in using the keyboard and interpreting error messages [1]. Our system aims to provide a mechanism for constructing a programme without the coder being literate. It can be used....L., Kristensen, S., Nielsen, B.W., Grønbæk, K., Designing an augmented reality board game with children: the battleboard 3D experience, In Proc. IDC 2004, ACM Press. 3. Bekker, A., Kruger C., Usability and educational review on GameBlocks and Body Ping Pong...

Computer-games for gravitational wave science outreach: Black Hole Pong and Space Time Quest

International Nuclear Information System (INIS)

Carbone, L; Bond, C; Brown, D; Brückner, F; Grover, K; Lodhia, D; Mingarelli, C M F; Fulda, P; Smith, R J E; Unwin, R; Vecchio, A; Wang, M; Whalley, L; Freise, A

2012-01-01

We have established a program aimed at developing computer applications and web applets to be used for educational purposes as well as gravitational wave outreach activities. These applications and applets teach gravitational wave physics and technology. The computer programs are generated in collaboration with undergraduates and summer students as part of our teaching activities, and are freely distributed on a dedicated website. As part of this program, we have developed two computer-games related to gravitational wave science: 'Black Hole Pong' and 'Space Time Quest'. In this article we present an overview of our computer related outreach activities and discuss the games and their educational aspects, and report on some positive feedback received.

An early story of Kho Ping Hoo

Directory of Open Access Journals (Sweden)

CW Watson

2017-05-01

Full Text Available Kho Ping Hoo (1926–1994 is the most well-known of all Indonesian writers of popular silat stories, largely set in China, which describe the adventures and romances of legendary heroes famed for their skill in martial arts. It is less well-known that he began his career writing critical stories about socio-economic conditions in the late 50s and early 60s. This paper discusses one of these stories. It places the story in the context of political developments of the time, in particular as they affected the Chinese Indonesian community. The paper argues that this story and one or two others like it come at the end of a tradition of Sino-Indonesian literature which had flourished from the end of the nineteenth century until the mid-1950s. After 1960, Chinese-Indonesian writers cease writing realist fiction of any kind and write either silat stories or romantic stories set in middle class urban environments.

High precision simple interpolation asynchronous FIFO based on ACEX1K30 for HIRFL-CSRe

International Nuclear Information System (INIS)

Li Guihua; Qiao Weimin; Jing Lan

2008-01-01

High precision simple interpolation asynchronous FIFO of HIRFL-CSRe was developed based on the ACEX1K30 FPGA in VHDL Hardware Description language. The FIFO runs in FPGA of DSP module of HIRFL-CSRe. The input data of FIFO is from DSP data bus and the output data is to DAC data bus. It's kernel adopts double buffer ping-pong mode and it can implement simple interpolation inside FPGA. The module can control out- put data time delay in 40 ns. The experimental results indicate that this module is practical and accurate to HIRFL-CSRe. (authors)

Success for ``Physics on Stage'' Festival in Geneva

Science.gov (United States)

Madsen, C.; West, R.

2000-12-01

Can you imagine how much physics is in a simple match of ping-pong, in throwing a boomerang, or in a musical concert? Physics is all around us and governs our lives. But who is going to maintain these technologies and develop new ones in the future? Recent surveys show a frightening decline of interest in physics and technology among E u r o p e 's citizens, especially school children. Fewer and fewer young people enrol in physics courses at Europe's universities while scepticism towards science and technology is spreading and causing great concern among governments and educators.

Cryptanalysis of an Improved Flexible Ping-Pong Protocol in Perfect and Imperfect Quantum Channels

International Nuclear Information System (INIS)

Bin-Bin, Zhang; Da-Qing, Wang; Shan-Shan, Huang; Yu, Liu

2009-01-01

We recently proposed a flexible quantum secure direct communication protocol [Chin. Phys. Lett. 23 (2006) 3152]. By analyzing its security in the perfect channel from the aspect of quantum information theory, we find that an eavesdropper is capable of stealing all the information without being detected. Two typical attacks are presented to illustrate this point. A solution to this loophole is also suggested and we show its powerfulness against the most general individual attack in the ideal case. We also discuss the security in the imperfect case when there is noise and loss

Lossless quantum data compression and secure direct communication

Science.gov (United States)

Boström, Kim

2004-07-01

This thesis deals with the encoding and transmission of information through a quantum channel. A quantum channel is a quantum mechanical system whose state is manipulated by a sender and read out by a receiver. The individual state of the channel represents the message. The two topics of the thesis comprise 1) the possibility of compressing a message stored in a quantum channel without loss of information and 2) the possibility to communicate a message directly from one party to another in a secure manner, that is, a third party is not able to eavesdrop the message without being detected. The main results of the thesis are the following. A general framework for variable-length quantum codes is worked out. These codes are necessary to make lossless compression possible. Due to the quantum nature of the channel, the encoded messages are in general in a superposition of different lengths. It is found to be impossible to compress a quantum message without loss of information if the message is not apriori known to the sender. In the other case it is shown that lossless quantum data compression is possible and a lower bound on the compression rate is derived. Furthermore, an explicit compression scheme is constructed that works for arbitrarily given source message ensembles. A quantum cryptographic protocol - the “ping-pong protocol” - is presented that realizes the secure direct communication of classical messages through a quantum channel. The security of the protocol against arbitrary eavesdropping attacks is proven for the case of an ideal quantum channel. In contrast to other quantum cryptographic protocols, the ping-pong protocol is deterministic and can thus be used to transmit a random key as well as a composed message. The protocol is perfectly secure for the transmission of a key, and it is quasi-secure for the direct transmission of a message. The latter means that the probability of successful eavesdropping exponentially decreases with the length of the

An investigation of player to player character identification via personal pronouns

DEFF Research Database (Denmark)

Hichens, Michael; Drachen, Anders; Richards, Deborah

2012-01-01

The player character is an important feature of many games, where it is through the character that the player interacts with game world. There has been considerable interest in the relationship between the player and the player character. Much of this work has examined the identification of players......, third) as an indication of the relationship between player and character. Results indicate that the presence of story and information about the player character had no effect on identification with the plater character. However, characteristics of the players, particularly gender and general experience...... in playing video games, did have a statistically significant affect, indicating that different levels of identification are more dependent on the player than on the game. This indicates that players are not a homogeneous group with respect to player character identification and is an important consideration...

The decline of Falkland Islands penguins in the presence of a commercial fishing industry La disminución de los pingüinos de las Islas Falklands en la presencia de actividades de pesca comercial

Directory of Open Access Journals (Sweden)

MIKE BINGHAM

2002-12-01

Islands Government to exclude large-scale commercial fishing close to penguin breeding sitesLas islas Falklands son un lugar importante para tres especies de pingüinos, pingüino papua (Pygoscelis papua, pingüino de penacho amarillo (Eudyptes c.chrysocome y pingüino de Magallanes (Spheniscus magallanicus. Recientemente estas especies han disminuido 84 % en estas islas. En la costa de Sudamérica los pingüinos no disminuyeron. Se sospecha que la causa es una reducción de peces y calamares debido a los barcos de pesca comercial que operan en aguas de las Islas Falklands. En 1995 el pingüino papua y el pingüino penacho amarillo terminaron sus disminuciones y ya parece que sus poblaciones están en equilibrio, pero en un número mucho mas bajo que antes que los pescadores comenzaron 20 años atrás. El pingüino de Magallanes todavía disminuye en las Islas Falklands. El pingüino de Magallanes depende más de especies de calamares y peces capturados por barcos de pesca comercial. Avisos de protección de la fauna no fueron suficientes para impedir que 1998 comenzaras exploraciones petroleras en las Islas Falklands. Tres derrames de petróleo ocurrieron en cinco meses, y cientos de pingüinos murieron. La torre de perforación se fue después de cinco meses, y no ocurrieron más derrames de petróleo. Nuevamente van a comenzar a buscar petróleo, sin mejorar la protección para la fauna. El turismo ha crecido rápidamente en las Islas Falklands, y la mayoría de los turistas llegan para ver los pingüinos. Investigaciones de poblaciones y éxito reproductivo indican que aún no hay efectos perjudiciales para los pingüinos por esta actividad. En este trabajo se investigan las causas potenciales de la disminución de pingüinos en las Islas Falklands y se hacen compariciones con poblaciones en Chile que parecen saludables

The NBA’s Maximum Player Salary and the Distribution of Player Rents

Directory of Open Access Journals (Sweden)

Kelly M. Hastings

2015-03-01

Full Text Available The NBA’s 1999 Collective Bargaining Agreement (CBA included provisions capping individual player pay in addition to team payrolls. This study examines the effect the NBA’s maximum player salary on player rents by comparing player pay from the 1997–1998 and 2003–2004 seasons while controlling for player productivity and other factors related to player pay. The results indicate a large increase in the pay received by teams’ second highest and, to a lesser extent, third highest paid players. We interpret this result as evidence that the adoption of the maximum player salary shifted rents from stars to complementary players. We also show that the 1999 CBA’s rookie contract provisions reduced salaries of early career players.

Experimental aspects of deterministic secure quantum key distribution

Energy Technology Data Exchange (ETDEWEB)

Walenta, Nino; Korn, Dietmar; Puhlmann, Dirk; Felbinger, Timo; Hoffmann, Holger; Ostermeyer, Martin [Universitaet Potsdam (Germany). Institut fuer Physik; Bostroem, Kim [Universitaet Muenster (Germany)

2008-07-01

Most common protocols for quantum key distribution (QKD) use non-deterministic algorithms to establish a shared key. But deterministic implementations can allow for higher net key transfer rates and eavesdropping detection rates. The Ping-Pong coding scheme by Bostroem and Felbinger[1] employs deterministic information encoding in entangled states with its characteristic quantum channel from Bob to Alice and back to Bob. Based on a table-top implementation of this protocol with polarization-entangled photons fundamental advantages as well as practical issues like transmission losses, photon storage and requirements for progress towards longer transmission distances are discussed and compared to non-deterministic protocols. Modifications of common protocols towards a deterministic quantum key distribution are addressed.

Cellobiose Dehydrogenase Inhibition of Polymerization of Phenolic Compounds and Enhancing Lignin Degradation by Lignina.

Science.gov (United States)

Fang, Jing; Liu, Wen; Gao, Pei-Ji

1999-01-01

The kinetic behavior of cellobiose dehydrogenase (CDH) was investigated by steady-state initial velocity studies. Variation in the concentration of one substrate led to changes in K(m) and V(max) of the other substrate. The results were consistent with a ping-pong mechanism. In the presence of cellobiose, CDH could reduce many oxidized products catalyzed by soybean hull peroxidase (SHP). The oxidation product of 1-hydroxybenzotriazole (HBT) catalyzed by SHP inactivated the enzyme itself however, CDH could prevent SHP from inactivation by reducing the oxidation product of HBT. CDH could also inhibit the polymerization of phenolic compounds catalyzed by SHP. It was found that the addition of CDH could enhance kraft pulp lignin degradation by ligninases.

Loominguliste ja uuenduslike ideede rakendamisega seotud pinged / Maureen McLaughlin, Mary Ellen Vogt ; tõlkinud Tiina Nurm

Index Scriptorium Estoniae

McLaughlin, Maureen

2000-01-01

Selleks, et saaks toimuda tulemuslik ja uuenduslik aineõpetus, tuleb teadvustada ja ületada pinged, mis on seotud loovideede rakendamisega. Pingetekitajad, millega õpetajad uuenduslike õpetamis- ja õppimistoimingute rakendamisel võivad kokku puutuda, on järgmised : aeg, ainekavad, tekstid ja muud allikad, oletatav loovuse puudumine, ebakõla uuenduste ja reaalsuse vahel, õpilaste erinevus, tunni organiseerimine ja läbiviimine, hindamine ja hinnangu andmine, õpilaste usaldamine

Player-Character Dynamics in Multi- Player Role Playing Games

DEFF Research Database (Denmark)

Tychsen, Anders; McIlwain, D.; Brolund, T.

2007-01-01

This paper presents the results of a comprehensive empirical study of the impact of integrating complex game characters in multi-player Role Playing Games across tabletop and digital formats. Players were provided with characters that had detailed background history, personality and goals. Player...

TRAF4 and Castration-Resistant Prostate Cancer

Science.gov (United States)

2017-10-01

AWARD NUMBER: W81XWH-15-1-0536 TITLE: TRAF4 and Castration-Resistant Prostate Cancer PRINCIPAL INVESTIGATOR: Ping Yi CONTRACTING...Castration Resistant prostate cancer 5b. GRANT NUMBER W81XWH-15-1-0536 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Ping Yi 5d. PROJECT NUMBER 5e. TASK...to be a critical player in castration-resistant prostate cancers . It was suggested that the function of AR in CRPC is not to turn on the same

Librarians as Advocates of Social Media for Researchers: A Social Media Project Initiated by Linköping University Library, Sweden

Science.gov (United States)

Persson, Sassa; Svenningsson, Maria

2016-01-01

Librarians at Linköping University help researchers keep abreast of developments in their fields and to increase the visibility of their work. Strategic, professional use of social media ought to be an essential part of a researcher's communication strategy. This article investigates the level of awareness of the professional use of social media…

The Anthropometric Characteristics of Futsal Players Compared with Professional Soccer Players

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Burdukiewicz Anna

2014-08-01

Full Text Available Purpose. The aim of the study was to compare the morphological characteristics of experienced futsal players with professional soccer players. Methods. The research sample included 22 university futsal players and 22 professional soccer players. Parameters including body height and mass, skinfold thicknesses of the trunk and extremities, lower limb length, trunk width, humerus and femur bone breadths, and the circumferences of the chest, hips, thighs, and calves were used to calculate various somatic indices. Somatotyping was performed using the Heath–carter method. Differences in the characteristics between the futsal and soccer players were analyzed using Student’s t test. Intragroup analysis was also performed on futsal players depending on player position and compared with the arithmetic means and standard deviations of all variables of the entire sample. Results. compared with their soccer-playing peers, the futsal players were shorter, weighed less, had shorter lower limbs, narrower hips, and smaller hip circumference and bone breadth values. In contrast, higher levels of body fat and endomorphy were noted in this group. The proportion of mesomorphs and ectomorphs were similar in both groups. Futsal goalkeepers were differentiated by greater subcutaneous adiposity and body mass. Defenders had the slimmest body shape, with relatively narrower shoulders and hips, smaller bone breadths, and lower levels of adiposity. The body build of wingers was slightly larger. Pivoters were characterized by greater body height and larger values for the characteristics measuring the lateral trunk dimensions. Conclusions. The observed morphological differences between futsal and soccer players were mainly in body height and height-associated characteristics. This indicates that no specialized approach in futsal recruitment is currently used. This points to the need to develop a specialized approach in the player recruitment stage, as the tactical and

A multi-attribute vertical handoff scheme for heterogeneous wireless networks

Directory of Open Access Journals (Sweden)

JI Xiaolong

2014-04-01

Full Text Available In order to meet the user demand for different services as well as to mitigate the Ping-pong effect caused by vertical handoff for wireless network,a multi-attribute vertical handoff scheme for heterogeneous wireless network is proposed.In the algorithm,a fuzzy logic method is used to make pre-decision.The optimal handoff target network is selected by a cost function of network which uses an Analytic Hierarchy Process to calculate the weights of SNR,delay,cost and user preference in different business scenarios.Simulation is performed in the environment which is overlapped by WiMAX and UMTS networks.Results show that the proposed approach can effectively reduce the number of handoff and power consumption in a condition to satisfy the user needs.

Fair and efficient network congestion control based on minority game

Science.gov (United States)

Wang, Zuxi; Wang, Wen; Hu, Hanping; Deng, Zhaozhang

2011-12-01

Low link utility, RTT unfairness and unfairness of Multi-Bottleneck network are the existing problems in the present network congestion control algorithms at large. Through the analogy of network congestion control with the "El Farol Bar" problem, we establish a congestion control model based on minority game(MG), and then present a novel network congestion control algorithm based on the model. The result of simulations indicates that the proposed algorithm can make the achievements of link utility closing to 100%, zero packet lose rate, and small of queue size. Besides, the RTT unfairness and the unfairness of Multi-Bottleneck network can be solved, to achieve the max-min fairness in Multi-Bottleneck network, while efficiently weaken the "ping-pong" oscillation caused by the overall synchronization.

Esterification of fatty acids using nylon-immobilized lipase in n-hexane: kinetic parameters and chain-length effects.

Science.gov (United States)

Zaidi, A; Gainer, J L; Carta, G; Mrani, A; Kadiri, T; Belarbi, Y; Mir, A

2002-02-28

The esterification of long-chain fatty acids in n-hexane catalyzed by nylon-immobilized lipase from Candida rugosa has been investigated. Butyl oleate (22 carbon atoms), oleyl butyrate (22 carbon atoms) and oleyl oleate (36 carbon atoms) were produced at maximum reaction rates of approximately equal to 60 mmol h(-1) g(-1) immobilized enzyme when the substrates were present in equimolar proportions at an initial concentration of 0.6 mol l(-1). The observed kinetic behavior of all the esterification reactions is found to follow a ping-pong bi-bi mechanism with competitive inhibition by both substrates. The effect of the chain-length of the fatty acids and the alcohols could be correlated to some mechanistic models, in accordance with the calculated kinetic parameters.

Enhancing base station connectivity with directional information of movement

Directory of Open Access Journals (Sweden)

Eugene Kim

2016-09-01

Full Text Available High-performance smartphones with various sensor capabilities, including the inertial measurement unit, allow us to have higher freedom to localize our movements and utilize them for other applications. In this paper, we present a simple method to estimate the heading of a user using only a digital compass, accelerometer, and gyroscope. Several experiments were conducted using an Apple iPhone. In addition, we also present an algorithm to reduce the number of handover attempts in a dense base station environment. A series of simulations were conducted on OPNET in various emulated environments to present the effectiveness of the proposed method. The simulation results show that our proposed algorithm effectively reduces the ping-pong effect in a dense base station environment.

A data acquisition system for coincidence imaging using a conventional dual head gamma camera

Science.gov (United States)

Lewellen, T. K.; Miyaoka, R. S.; Jansen, F.; Kaplan, M. S.

1997-06-01

A low cost data acquisition system (DAS) was developed to acquire coincidence data from an unmodified General Electric Maxxus dual head scintillation camera. A high impedance pick-off circuit provides position and energy signals to the DAS without interfering with normal camera operation. The signals are pulse-clipped to reduce pileup effects. Coincidence is determined with fast timing signals derived from constant fraction discriminators. A charge-integrating FERA 16 channel ADC feeds position and energy data to two CAMAC FERA memories operated as ping-pong buffers. A Macintosh PowerPC running Labview controls the system and reads the CAMAC memories. A CAMAC 12-channel scaler records singles and coincidence rate data. The system dead-time is approximately 10% at a coincidence rate of 4.0 kHz.

A data acquisition system for coincidence imaging using a conventional dual head gamma camera

International Nuclear Information System (INIS)

Lewellen, T.K.; Miyaoka, R.S.; Kaplan, M.S.

1996-01-01

A low cost data acquisition system (DAS) was developed to acquire coincidence data from an unmodified General Electric Maxxus dual head scintillation camera. A high impedance pick-off circuit provides position and energy signals to the DAS without interfering with normal camera operation. The signals are pulse-clipped to reduce pileup effects. Coincidence is determined with fast timing signals derived from constant fraction discriminators. A charge-integrating FERA 16 channel ADC feeds position and energy data to two CAMAC FERA memories operated as ping-pong buffers. A Macintosh PowerPC running Labview controls the system and reads the CAMAC memories. A CAMAC 12-channel scaler records singles and coincidence rate data. The system dead-time is approximately 10% at a coincidence rate of 4.0 kHz

Prospective Player-Reported Injuries in Female Youth Fast-Pitch Softball Players.

Science.gov (United States)

Smith, Matthew V; Davis, Randi; Brophy, Robert H; Prather, Heidi; Garbutt, Jane; Wright, Rick W

2015-01-01

There is a scarcity of literature evaluating injuries in youth fast-pitch softball players. To perform a descriptive analysis of player-reported injuries in youth fast-pitch softball position players and pitchers during a single select-level season. Prospective observation cohort study. Level 3. Ninety-eight athletes (48 pitchers, 50 position players) were followed for a single select fast-pitch softball season. Study participants completed web-based surveys every 3 weeks reporting injuries related to participation in fast-pitch softball. Injury was defined as pain causing cessation of participation in the current game or practice that prevents the player's return to that session or any pain that causes cessation of a player's customary participation on the day after the day of onset. The median age of the study participants was 14 years (range, 9-18 years). There were 49 reported injuries in 98 athletes. The average age was 13 years for those not injured and 14 years for those who were injured (P softball players. Better off-season and preseason conditioning may be a key factor for reducing pitching injuries. Recognition of injury patterns in fast-pitch softball players is critical to developing strategies to keep these athletes competing safely. © 2015 The Author(s).

N isotopes and N cycle in the TieShanPing subtropical forest ecosystem, Southwestern China.

Science.gov (United States)

Jiang, Chun-lai; Zhang, Xiao-Shan

2009-07-01

Nitrogen is essential for forest growth and forest stand development. It is commonly a limited factor for forest productivity. We examined delta (15)N values in soils and plants by studying the sources of N used by vegetation and cycles of N in a 43-year-old plantation of the TieShanPing forest ecosystem in southwestern China, dominated by massone pine (Pinus massoniana). The N concentration of plant materials ranges from 1.1% to 2.2%. The nitrogen concentration of P. massoniana was 1.3% while soils showed the concentration of 0.04-0.15%. Regarding natural abundance of (15)N, large significant variation (-6.0 per thousand to -3.8 per thousand) in delta (15)N values was observed among shrub and tree leaves. delta (15)N values were also significantly varied from -4.7 per thousand to -3.8 per thousand among the pioneer species in the plantation. Soil delta (15)N values (3.1-6.3 per thousand) were significantly enriched compared to those values in plant samples. Despite the negative delta (15)N values of the vegetation cover, the high delta (15)N values in the topsoil indicate that return of N to soils by litter-fall is minimal on TieShanPing and the present forests do not change very much the soil (15)N signals at the surface layer. The positive delta (15)N values may also indicate large N losses from the soil system vial leaching, volatilization and plant uptake.

Beam pinging, sweeping, shaking, and electron/ion collecting, at the Proton Storage Ring

International Nuclear Information System (INIS)

Hardek, T.W.; Macek, R.J.; Plum, M.A.; Wang, T.S.F.

1993-01-01

We have built, installed and tested a pinger for use as a general diagnostic at the Los Alamos Proton Storage Ring (PSR). Two 4-m-long parallel-plate electrodes with a plate spacing of 10.2 cm provide kicks of up to 1.1 mrad. A pair of solid-state pulsers may be operated in a single-pulse mode for beam pinging (tune measurements) or in a burst mode at up to 700 kHz pulse rates for beam sweeping. During our 1992 operating period we used the pinger for beam sweeping, for beam shaking, for measuring the tune shift, and we have used it as an ion chamber. Using the pinger as an ion chamber during production conditions has yielded some surprising results

Quantifying the uncertainties of climate change effects on the storage-yield and performance characteristics of the Pong multi-purpose reservoir, India

Directory of Open Access Journals (Sweden)

B. Soundharajan

2015-06-01

Full Text Available Climate change is predicted to affect water resources infrastructure due to its effect on rainfall, temperature and evapotranspiration. However, there are huge uncertainties on both the magnitude and direction of these effects. The Pong reservoir on the Beas River in northern India serves irrigation and hydropower needs. The hydrology of the catchment is highly influenced by Himalayan seasonal snow and glaciers, and Monsoon rainfall; the changing pattern of the latter and the predicted disappearance of the former will have profound effects on the performance of the reservoir. This study employed a Monte-Carlo simulation approach to characterise the uncertainties in the future storage requirements and performance of the reservoir. Using a calibrated rainfall-runoff (R-R model, the baseline runoff scenario was first simulated. The R-R inputs (rainfall and temperature were then perturbed using plausible delta-changes to produce simulated climate change runoff scenarios. Stochastic models of the runoff were developed and used to generate ensembles of both the current and climate-change perturbed future scenarios. The resulting runoff ensembles were used to simulate the behaviour of the reservoir and determine "populations" of reservoir storage capacity and performance characteristics. Comparing these parameters between the current and the perturbed provided the population of climate change effects which was then analysed to determine the uncertainties. The results show that contrary to the usual practice of using single records, there is wide variability in the assessed impacts. This variability or uncertainty will, no doubt, complicate the development of climate change adaptation measures; however, knowledge of its sheer magnitude as demonstrated in this study will help in the formulation of appropriate policy and technical interventions for sustaining and possibly enhancing water security for irrigation and other uses served by Pong reservoir.

El Riesgo de la Mora en el fletamento: ¿Cómo un juego de Ping Pong?

Directory of Open Access Journals (Sweden)

Javier Andrés Franco Zárate

2009-06-01

Full Text Available Uno de los contratos más usados hoy en día para transportar mercancías por mar es el contrato de fletamento. El presente artículo pretende hacer una presentación general de los efectos de la “demora” que se puede presentar, tanto de parte del fletador como de parte del fletante, en el cumplimiento de sus compromisos contractuales bien en un contrato de fletamento por tiempo, bien en un contrato de fletamento por viaje.

El Riesgo de la Mora en el fletamento: ¿Cómo un juego de Ping Pong?

Directory of Open Access Journals (Sweden)

Javier Andrés Franco Zárate

2009-07-01

Full Text Available Uno de los contratos más usados hoy en día para transportar mercancías por mar es el contrato de fletamento. El presente artículo pretende hacer una presentación general de los efectos de la “demora” que se puede presentar, tanto de parte del fletador como de parte del fletante, en el cumplimiento de sus compromisos contractuales bien en un contrato de fletamento por tiempo, bien en un contrato de fletamento por viaje.

Sotsiaal-majanduslikud pinged sotsiaalse konflikti eeldusena : (Tallinna ja Harjumaa materjali näitel) : [bakalaureusetöö] / Irina Borozdina ; Tartu Ülikool, õigusteaduskond ; juhendaja: Silvia Kaugia

Index Scriptorium Estoniae

Borozdina, Irina

2006-01-01

Inimkäitumist mõjutavad sotsiaal-majanduslikud pinged, olulisemad hälbekäitumise vormid (kuritegevus, alkoholism, narkomaania, prostitutsioon), sotsiaalse konflikti olemus, allikad, liigid, konflikti lahendamine (kohtuprotsess, vahekohus, läbirääkimised, vahendus) sotsiaalse eesmärgina

Bacillus anthracis o-succinylbenzoyl-CoA synthetase: reaction kinetics and a novel inhibitor mimicking its reaction intermediate.

Science.gov (United States)

Tian, Yang; Suk, Dae-Hwan; Cai, Feng; Crich, David; Mesecar, Andrew D

2008-11-25

o-Succinylbenzoyl-CoA (OSB-CoA) synthetase (EC 6.2.1.26) catalyzes the ATP-dependent condensation of o-succinylbenzoate (OSB) and CoA to form OSB-CoA, the fourth step of the menaquinone biosynthetic pathway in Bacillus anthracis. Gene knockout studies have highlighted this enzyme as a potential target for the discovery of new antibiotics. Here we report the first studies on the kinetic mechanism of B. anthracis OSB-CoA synthetase, classifying it as an ordered bi uni uni bi ping-pong mechanism. Through a series of pre-steady-state and steady-state kinetic studies in conjunction with direct binding studies, it is demonstrated that CoA, the last substrate to bind, strongly activates the first half-reaction after the first round of turnover. The activation of the first half-reaction is most likely achieved by CoA stabilizing conformations of the enzyme in the "F" form, which slowly isomerize back to the E form. Thus, the kinetic mechanism of OSB-CoA synthetase may be more accurately described as an ordered bi uni uni bi iso ping-pong mechanism. The substrate specificity of OSB-CoA synthetase was probed using a series of OSB analogues with alterations in the carboxylate groups. OSB-CoA shows a strong preference for OSB over all of the analogues tested as none were active except 4-[2-(trifluoromethyl)phenyl]-4-oxobutyric acid which exhibited a 100-fold decrease in k(cat)/K(m). On the basis of an understanding of OSB-CoA synthetase's kinetic mechanism and substrate specificity, a reaction intermediate analogue of OSB-AMP, 5'-O-{N-[2-(trifluoromethyl)phenyl]-4-oxobutyl}adenosine sulfonamide (TFMP-butyl-AMS), was designed and synthesized. This inhibitor was found to be an uncompetitive inhibitor to CoA and a mixed-type inhibitor to ATP and OSB with low micromolar inhibition constants. Collectively, these results should serve as an important forerunner to more detailed and extensive inhibitor design studies aimed at developing lead compounds against the OSB-CoA synthetase

Bacillus anthracis o-succinylbenzoyl-CoA synthetase: reaction kinetics and a novel inhibitor mimicking its reaction intermediate †

Science.gov (United States)

Tian, Yang; Suk, Dae-Hwan; Cai, Feng; Crich, David; Mesecar, Andrew D.

2009-01-01

O-succinylbenzoyl-CoA (OSB-CoA) synthetase (EC 6.2.1.26) catalyzes the ATP-dependent condensation of o-succinylbenzoate (OSB) and CoA to form OSB-CoA, the fourth step of the menaquinone biosynthetic pathway in Bacillus anthracis. Gene knockout studies have highlighted this enzyme as a potential target for the discovery of new antibiotics. Here we report the first studies on the kinetic mechanism of B. anthracis OSB-CoA synthetase, classifying it as an ordered Bi Uni Uni Bi ping-pong mechanism. Through a series of pre-steady-state and steady-state kinetic studies in conjunction with direct-binding studies, it is demonstrated that CoA, the last substrate to bind, strongly activates the first half-reaction after the first round of turnover. The activation of the first-half reaction is most likely achieved by CoA stabilizing conformations of the enzyme in the ‘F’ form, which slowly isomerize back to the E form. Thus, the kinetic mechanism of OSB-CoA synthetase may be more accurately described as an ordered Bi Uni Uni Bi Iso ping-pong mechanism. The substrate specificity of OSB-CoA synthetase was probed using a series of OSB analogs with alterations in the carboxylate groups. OSB-CoA shows a strong preference for OSB over all of the analogs tested as none were active except 4-(2-trifluoromethylphenyl)-4-oxobutyric acid which exhibited a 100-fold decrease in kcat/Km. Based on an understanding of OSB-CoA synthetase’s kinetic mechanism and substrate specificity, a reaction intermediate analog of OSB-AMP, 5’-O-(N-(2-trifluoromethylphenyl)-4-oxobutyl) adenosine sulfonamide (TFMP-butyl-AMS), was designed and synthesized. This inhibitor was found to be an uncompetitive inhibitor to CoA and a mixed-type inhibitor to ATP and OSB with low micromolar inhibition constants. Collectively, these results should serve as an important forerunner to more detailed and extensive inhibitor design studies aimed at developing lead compounds against the OSB-CoA synthetase class of

The Effectiveness Evaluation among Different Player-Matching Mechanisms in a Multi-Player Quiz Game

Science.gov (United States)

Tsai, Fu-Hsing

2016-01-01

This study aims to investigate whether different player-matching mechanisms in educational multi-player online games (MOGs) can affect students' learning performance, enjoyment perception and gaming behaviors. Based on the multi-player quiz game, TRIS-Q, developed by Tsai, Tsai and Lin (2015) using a free player-matching (FPM) mechanism, the same…

Frontal lobe function in chess players.

Science.gov (United States)

Nejati, Majid; Nejati, Vahid

2012-01-01

Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST) data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players don't have any preference in any stage of Stroop test. Chess players don't have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.

A comparison of static near stereo acuity in youth baseball/softball players and non-ball players.

Science.gov (United States)

Boden, Lauren M; Rosengren, Kenneth J; Martin, Daniel F; Boden, Scott D

2009-03-01

Although many aspects of vision have been investigated in professional baseball players, few studies have been performed in developing athletes. The issue of whether youth baseball players have superior stereopsis to nonplayers has not been addressed specifically. The purpose of this study was to determine if youth baseball/softball players have better stereo acuity than non-ball players. Informed consent was obtained from 51 baseball/softball players and 52 non-ball players (ages 10 to 18 years). Subjects completed a questionnaire, and their static near stereo acuity was measured using the Randot Stereotest (Stereo Optical Company, Chicago, Illinois). Stereo acuity was measured as the seconds of arc between the last pair of images correctly distinguished by the subject. The mean stereo acuity score was 25.5 +/- 1.7 seconds of arc in the baseball/softball players and 56.2 +/- 8.4 seconds of arc in the non-ball players. This difference was statistically significant (P softball players had significantly better static stereo acuity than non-ball players, comparable to professional ball players.

Tales of Recombinant Femininity: "The Reincarnation of Golden Lotus," the "Chin P'ing Mei," and the Politics of Melodrama in Hong Kong.

Science.gov (United States)

Fore, Steve

1993-01-01

Examines the film "The Reincarnation of Golden Lotus" and the text upon which it is loosely based, the "Chin P'ing Mei," and the relationship between it and modern Chinese culture. States that the film's screenplay is much less an adaptation of the source novel than it is a female-centered reworking of a particular narrative…

Veto players

NARCIS (Netherlands)

Warntjen, Andreas; Dowding, Keith

2010-01-01

Veto players are political actors whose consent is necessary to adopt a new policy. Put otherwise, they have veto power which allows them to prevent a change to the status quo. The concept is crucial to the influential veto player theory developed by George Tsebelis. Building on earlier work in

Quantum direct communication protocol strengthening against Pavičić’s attack

Science.gov (United States)

Zhang, Bo; Shi, Wei-Xu; Wang, Jian; Tang, Chao-Jing

2015-12-01

A quantum circuit providing an undetectable eavesdropping of information in message mode, which compromises all two-state ψ-ϕ quantum direct communication (QDC) protocols, has been recently proposed by Pavičić [Phys. Rev. A 87 (2013) 042326]. A modification of the protocol’s control mode is proposed, which improves users’ 25% detection probability of Eve to 50% at best, as that in ping-pong protocol. The modification also improves the detection probability of Wójcik’s attack [Phys. Rev. Lett 90 (2003) 157901] to 75% at best. The resistance against man-in-the-middle (MITM) attack as well as the discussion of security for four Bell state protocols is presented. As a result, the protocol security is strengthened both theoretically and practically, and quantum advantage of superdense coding is restored.

Frontal Lobe Function in Chess Players

Directory of Open Access Journals (Sweden)

Vahid Nejati

2012-05-01

Full Text Available Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players dont have any preference in any stage of Stroop test. Chess players dont have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.

Subsurface deformation measurements during a fast shallow landslide triggered by rainfall

Science.gov (United States)

Askarinejad, Amin; Springman, Sarah M.; Akca, Devrim; Bleiker, Ernst; Gruen, Armin

2010-05-01

A forested area in Ruedlingen, northern Switzerland, was selected to investigate the geotechnical and hydrological response of a steep slope prior to a rainfall induced failure. Artificial rainfall was applied according to a pre-planned schedule and parameters such as pore water pressure, volumetric water content, horizontal soil pressure, temperature, piezometric water level and subsurface deformations were monitored. The latter were determined from four deformation probes that were developed in the Institute for Geotechnical Engineering, ETHZ. Strain gauges have been attached at a regular spacing along a long, slender, flexible plate to enable measurements of bending strain to be made at different points along it. The strain gauges were connected as 'half bridges' to minimize the temperature effects. A biaxial inclinometer was also installed on the top of the plate, 20 cm above the soil surface, to measure the tilt above ground level, providing more boundary conditions to determine the deformed shape of the probe. The probe is installed vertically inside the soil, while the lowest part is grouted into the stiffer layer under the topsoil, and is assumed to be stable and without any rotation. Bending strains and the inclination at the top of the probe are sampled at a frequency of 100 Hz. These are input into an algorithm to determine a polynomial relationship of deformations and rotations with depth, so that the initiation of slow movements and propagation of failure during fast soil mass movements can be examined. A 4-camera arrangement was used for the image acquisition to monitor surface movements using photogrammetric analyses. Approximately 250 white ping-pong balls were attached to the ground and used as target points. Using a network simulation tool that was developed in-house, an a priori point positioning accuracy of the ping-pong balls was estimated to be ± 10.3 mm along the horizontal direction and ± 3.5 mm in the vertical direction. The cameras

Prospective Player-Reported Injuries in Female Youth Fast-Pitch Softball Players

Science.gov (United States)

Smith, Matthew V.; Davis, Randi; Brophy, Robert H.; Prather, Heidi; Garbutt, Jane; Wright, Rick W.

2015-01-01

Background: There is a scarcity of literature evaluating injuries in youth fast-pitch softball players. Purpose: To perform a descriptive analysis of player-reported injuries in youth fast-pitch softball position players and pitchers during a single select-level season. Study Design: Prospective observation cohort study. Level of Evidence: Level 3. Methods: Ninety-eight athletes (48 pitchers, 50 position players) were followed for a single select fast-pitch softball season. Study participants completed web-based surveys every 3 weeks reporting injuries related to participation in fast-pitch softball. Injury was defined as pain causing cessation of participation in the current game or practice that prevents the player’s return to that session or any pain that causes cessation of a player’s customary participation on the day after the day of onset. Results: The median age of the study participants was 14 years (range, 9-18 years). There were 49 reported injuries in 98 athletes. The average age was 13 years for those not injured and 14 years for those who were injured (P softball players. Better off-season and preseason conditioning may be a key factor for reducing pitching injuries. Clinical Relevance: Recognition of injury patterns in fast-pitch softball players is critical to developing strategies to keep these athletes competing safely. PMID:26502442

A COMPARISON OF THE ANTHROPOMETRIC PARAMETERS BETWEEN BASKETBALL PLAYERS, HANDBALL PLAYERS AND VOLLEYBALL PLAYERS

OpenAIRE

Florian Miftari; Juel Jarani; Dhimitraq Stratoberdha; Hazir Salihu

2017-01-01

The purpose of this study was to compare the anthropometric measurement to the professional players of the three different disciplines of basketball, handball and volleyball. . For each player anthropometric measurements such as weight, body height, waist circumference, BMI and skinfold calculation on different sports are performed. Differences in terms of anthropometric measurements were assessed by independent static tests and the differences for each variable for each sport were evaluated ...

Co-option of the piRNA pathway for germline-specific alternative splicing of C. elegans TOR.

Science.gov (United States)

Barberán-Soler, Sergio; Fontrodona, Laura; Ribó, Anna; Lamm, Ayelet T; Iannone, Camilla; Cerón, Julián; Lehner, Ben; Valcárcel, Juan

2014-09-25

Many eukaryotic genes contain embedded antisense transcripts and repetitive sequences of unknown function. We report that male germline-specific expression of an antisense transcript contained in an intron of C. elegans Target of Rapamycin (TOR, let-363) is associated with (1) accumulation of endo-small interfering RNAs (siRNAs) against an embedded Helitron transposon and (2) activation of an alternative 3' splice site of TOR. The germline-specific Argonaute proteins PRG-1 and CSR-1, which participate in self/nonself RNA recognition, antagonistically regulate the generation of these endo-siRNAs, TOR mRNA levels, and 3' splice-site selection. Supply of exogenous double-stranded RNA against the region of sense/antisense overlap reverses changes in TOR expression and splicing and suppresses the progressive multigenerational sterility phenotype of prg-1 mutants. We propose that recognition of a "nonself" intronic transposon by endo-siRNAs/the piRNA system provides physiological regulation of expression and alternative splicing of a host gene that, in turn, contributes to the maintenance of germline function across generations. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Player and Game Characteristics and Head Impacts in Female Youth Ice Hockey Players.

Science.gov (United States)

Reed, Nick; Taha, Tim; Greenwald, Richard; Keightley, Michelle

2017-08-01

  Despite the growing popularity of ice hockey among female youth and interest in the biomechanics of head impacts in sport, the head impacts sustained by this population have yet to be characterized.   To describe the number of, biomechanical characteristics of, and exposure to head impacts of female youth ice hockey players during competition and to investigate the influences of player and game characteristics on head impacts.   Cohort study.   Twenty-seven female youth ice hockey players (mean age = 12.5 ± 0.52 years) wore instrumented ice hockey helmets during 66 ice hockey games over a 3-year period. Data specific to player, game, and biomechanical head impact characteristics were recorded. A multiple regression analysis identified factors most associated with head impacts of greater frequency and severity.   A total of 436 total head impacts were sustained during 6924 minutes of active ice hockey participation (0.9 ± 0.6 impacts per player per game; range, 0-2.1). A higher body mass index (BMI) significantly predicted a higher number of head impacts sustained per game (P = .008). Linear acceleration of head impacts was greater in older players and those who played the forward position, had a greater BMI, and spent more time on the ice (P = .008), whereas greater rotational acceleration was present in older players who had a greater BMI and played the forward position (P = .008). During tournament games, increased ice time predicted increased severity of head impacts (P = .03).   This study reveals for the first time that head impacts are occurring in female youth ice hockey players, albeit at a lower rate and severity than in male youth ice hockey players, despite the lack of intentional body checking.

Active Learning for Player Modeling

DEFF Research Database (Denmark)

Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad

2015-01-01

Learning models of player behavior has been the focus of several studies. This work is motivated by better understanding of player behavior, a knowledge that can ultimately be employed to provide player-adapted or personalized content. In this paper, we propose the use of active learning for player...... experience modeling. We use a dataset from hundreds of players playing Infinite Mario Bros. as a case study and we employ the random forest method to learn mod- els of player experience through the active learning approach. The results obtained suggest that only part of the dataset (up to half the size...... that the method can be used online during the content generation process where the mod- els can improve and better content can be presented as the game is being played....

Impact locations and concussion outcomes in high school football player-to-player collisions.

Science.gov (United States)

Kerr, Zachary Y; Collins, Christy L; Mihalik, Jason P; Marshall, Stephen W; Guskiewicz, Kevin M; Comstock, R Dawn

2014-09-01

Little research has examined concussion outcomes in terms of impact location (ie, the area on the head in which the impact occurred). This study describes the epidemiology of concussions resulting from player-to-player collision in high school football by impact location. National High School Sports-Related Injury Surveillance Study data (2008/2009-2012/2013) were analyzed to calculate rates and describe circumstances of football concussion (eg, symptomology, symptom resolution time, return to play) resulting from player-to-player collisions by impact location (ie, front-, back-, side-, and top-of-the-head). Most concussions resulting from player-to-player collisions occurred from front-of-the-head (44.7%) and side-of-the-head (22.3%) impacts. Number of symptoms reported, prevalence of reported symptoms, symptom resolution time, and length of time to return to play were not associated with impact location. However, a larger proportion of football players sustaining concussions from top-of-the-head impacts experienced loss of consciousness (8.0%) than those sustaining concussions from impacts to other areas of the head (3.5%) (injury proportion ratio 2.3; 95% confidence interval 1.2-4.2; P = .008). Players had their head down at the time of impact in a higher proportion of concussions caused by top-of-the-head impacts (86.4%) than concussions from impacts to other areas of the head (24.0%) (injury proportion ratio 3.6; 95% confidence interval 3.2-4.0; P impact location. Recommended strategies for reducing the proportion of top-of-the-head impacts include improved education regarding tackling with proper "head-up" technique. Copyright © 2014 by the American Academy of Pediatrics.

Physical fitness of elite Belgian soccer players by player position.

Science.gov (United States)

Boone, Jan; Vaeyens, Roel; Steyaert, Adelheid; Vanden Bossche, Luc; Bourgois, Jan

2012-08-01

The purpose of this study was to gain an insight into the physical and physiological profile of elite Belgian soccer players with specific regard to the player's position on the field. The sample consisted of 289 adult players from 6 different first division teams. The players were divided into 5 subgroups (goalkeepers, center backs, full backs, midfielders, and strikers) according to their self-reported best position on the field. The subjects performed anaerobic (10-m sprint, 5 × 10-m shuttle run [SR], squat jump [SJ], and countermovement jump [CMJ]) and aerobic (incremental running protocol) laboratory tests. The strikers had significantly shorter sprinting times (5-, 5- to 10-m time, and SR) compared with the midfielders, center backs, and goalkeepers, whereas the full backs were also significantly faster compared with the goalkeepers and the center backs. The goalkeepers and the center backs displayed higher jumping heights (total mean SJ = 40.7 ± 4.6 cm and CMJ = 43.1 ± 4.9 cm) compared with the other 3 positions, whereas the strikers also jumped higher than the full backs and the midfielders did. Regarding the aerobic performance, both full backs and the midfielders (61.2 ± 2.7 and 60.4 ± 2.8 ml · min(-1) · kg(-1), respectively) had a higher VO2max compared with the strikers, center backs, and goalkeepers (56.8 ± 3.1, 55.6 ± 3.5, and 52.1 ± 5.0 ml · min(-1) · kg(-1), respectively). From this study, it could be concluded that players in different positions have different physiological characteristics. The results of this study might provide useful insights for individualized conditional training programs for soccer players. Aside from the predominant technical and tactical skills, a physical profile that is well adjusted to the position on the field might enhance game performance.

High School Football Players Use Their Helmets to Tackle Other Players Despite Knowing the Risks.

Science.gov (United States)

Kuriyama, Andrew M; Nakatsuka, Austin S; Yamamoto, Loren G

2017-03-01

There is greater attention to head-related injuries and concussions in American football. The helmet's structural safety and the way that football players use their helmets are important in preventing head injuries. Current strategies include penalizing players for high-risk behavior such as leading with their helmet or hitting an opposing player above the shoulder. Passive strategies include helmet modification to better protect the head of the players or to change the playing style of the players. Hawai'i high school varsity football players were surveyed to determine how they use their helmets and how a new helmet design would affect their style of play. One hundred seventy-seven surveys were completed; 79% said that they used their helmet to hit an opposing player during a tackle and 46% said they made this contact intentionally. When asked about modifying helmets with a soft material on the outside, 48% said they thought putting a soft cover over a regular helmet would protect their head better. However, many participants said that putting a soft cover over their regular helmet was a bad idea for various reasons. Most young football players use their helmets to block or tackle despite being taught they would be penalized or potentially injured if they did so. By gaining a better understanding of why and how players use their helmets and how they would respond to new helmet designs, steps can be taken to reduce head injuries for all levels of play.

Pros and cons of vertical integration between clinical medicine and basic science within a problem-based undergraduate medical curriculum: examples and experiences from Linköping, Sweden.

Science.gov (United States)

Dahle, L O; Brynhildsen, J; Behrbohm Fallsberg, M; Rundquist, I; Hammar, M

2002-05-01

Problem-based learning (PBL), combined with early patient contact, multiprofessional education and emphasis on development of communications skills, has become the basis for the medical curriculum at the Faculty of Health Sciences in Linköping (FHS), Sweden, which was started in 1986. Important elements in the curriculum are vertical integration, i.e. integration between the clinical and basic science parts of the curriculum and horizontal integration between different subject areas. This article discusses the importance of vertical integration in an undergraduate medical curriculum, according to experiences from the Faculty of Health Sciences in Linköping, and also give examples on how it has been implemented during the latest 15 years. Results and views put forward in published articles concerning vertical integration within undergraduate medical education are discussed in relation to the experiences in Linköping. Vertical integration between basic sciences and clinical medicine in a PBL setting has been found to stimulate profound rather than superficial learning, and thereby stimulates better understanding of important biomedical principles. Integration probably leads to better retention of knowledge and the ability to apply basic science principles in the appropriate clinical context. Integration throughout the whole curriculum entails a lot of time and work in respect of planning, organization and execution. The teachers have to be deeply involved and enthusiastic and have to cooperate over departmental borders, which may produce positive spin-off effects in teaching and research but also conflicts that have to be resolved. The authors believe vertical integration supports PBL and stimulates deep and lifelong learning.

Wrinkling of Pressurized Elastic Shells

KAUST Repository

Vella, Dominic

2011-10-01

We study the formation of localized structures formed by the point loading of an internally pressurized elastic shell. While unpressurized shells (such as a ping-pong ball) buckle into polygonal structures, we show that pressurized shells are subject to a wrinkling instability. We study wrinkling in depth, presenting scaling laws for the critical indentation at which wrinkling occurs and the number of wrinkles formed in terms of the internal pressurization and material properties of the shell. These results are validated by numerical simulations. We show that the evolution of the wrinkle length with increasing indentation can be understood for highly pressurized shells from membrane theory. These results suggest that the position and number of wrinkles may be used in combination to give simple methods for the estimation of the mechanical properties of highly pressurized shells. © 2011 American Physical Society.

A Velocity-Aware Handover Trigger in Two-Tier Heterogeneous Networks

Directory of Open Access Journals (Sweden)

Asmae Ait Mansour

2018-01-01

Full Text Available The unexpected change in user equipment (UE velocity is recognized as the primary explanation for poor handover quality. In order to resolve this issue, while limiting ping-pong (PP events we carefully and dynamically optimized handover parameters for each UE unit according to its velocity and the coverage area of the access point (AP. In order to recognize any variations in velocity, we applied Allan variance (AVAR to the received signal strength (RSS from the serving AP. To assess our approach, it was essential to configure a heterogeneous network context (LTE-WiFi and interconnect Media-Independent Handover (MIH and Proxy Mobile IPv6 (PMIPv6 for seamless handover. Reproduction demonstrated that our approach does not only result in a gain in relatively accurate velocity but in addition reduces the number of PP and handover failures (HOFs.

Information literacy progression within the Environmental science program at Linköping University

Directory of Open Access Journals (Sweden)

Kajsa Gustafsson Åman

2013-12-01

Full Text Available Since the Environmental Science program at Linköping University started 1998 the author has been liaison librarian. The program is a three-year candidate program with approximately 60 students enrolled per year. Information literacy is of vital importance for the teachers and the students. Collaboration between the liaison librarian, the teachers and the administrator is the fundament. During the years a curriculum for Information literacy has evolved. The initiative for the evolvement comes from both librarian and teachers. The program consists today of fifteen different parts with education in information literacy with a progression during the three-year program. Special concern is given to progression, learning design, learning environments and quality development. An important part is appendixes in connection to the student essay. The appendixes consist of reflections on the search of information for the essay in order to make the students more conscious about their Information Literacy processes.

Technical player profiles related to the physical fitness of young female volleyball players predict team performance.

Science.gov (United States)

Dávila-Romero, C; Hernández-Mocholí, M A; García-Hermoso, A

2015-03-01

This study is divided into three sequential stages: identification of fitness and game performance profiles (individual player performance), an assessment of the relationship between these profiles, and an assessment of the relationship between individual player profiles and team performance during play (in championship performance). The overall study sample comprised 525 (19 teams) female volleyball players aged 12-16 years and a subsample (N.=43) used to examine study aims one and two was selected from overall sample. Anthropometric, fitness and individual player performance (actual game) data were collected in the subsample. These data were analyzed through clustering methods, ANOVA and independence chi-square test. Then, we investigated whether the proportion of players with the highest individual player performance profile might predict a team's results in the championship. Cluster analysis identified three volleyball fitness profiles (high, medium, and low) and two individual player performance profiles (high and low). The results showed a relationship between both types of profile (fitness and individual player performance). Then, linear regression revealed a moderate relationship between the number of players with a high volleyball fitness profile and a team's results in the championship (R2=0.23). The current study findings may enable coaches and trainers to manage training programs more efficiently in order to obtain tailor-made training, identify volleyball-specific physical fitness training requirements and reach better results during competitions.

Protective Equipment and Player Characteristics Associated With the Incidence of Sport-Related Concussion in High School Football Players

Science.gov (United States)

McGuine, Timothy A.; Hetzel, Scott; McCrea, Michael; Brooks, M. Alison

2015-01-01

Background The incidence of sport-related concussion (SRC) in high school football is well documented. However, limited prospective data are available regarding how player characteristics and protective equipment affect the incidence of SRC. Purpose To determine whether the type of protective equipment (helmet and mouth guard) and player characteristics affect the incidence of SRC in high school football players. Design Cohort study; Level of evidence, 2. Methods Certified athletic trainers (ATs) at each high school recorded the type of helmet worn (brand, model, purchase year, and recondition status) by each player as well as information regarding players’ demographics, type of mouth guard used, and history of SRC. The ATs also recorded the incidence and days lost from participation for each SRC. Incidence of SRC was compared for various helmets, type of mouth guard, history of SRC, and player demographics. Results A total of 2081 players (grades 9–12) enrolled during the 2012 and/or 2013 football seasons (2287 player-seasons) and participated in 134,437 football (practice or competition) exposures. Of these players, 206 (9%) sustained a total of 211 SRCs (1.56/1000 exposures). There was no difference in the incidence of SRC (number of helmets, % SRC [95% CI]) for players wearing Riddell (1171, 9.1% [7.6%–11.0%]), Schutt (680, 8.7% [6.7%–11.1%]), or Xenith (436, 9.2% [6.7%–12.4%]) helmets. Helmet age and recondition status did not affect the incidence of SRC. The rate of SRC (hazard ratio [HR]) was higher in players who wore a custom mouth guard (HR = 1.69 [95% CI, 1.20–2.37], P football players. Players who had sustained an SRC within the previous 12 months were more likely to sustain an SRC than were players without a history of SRC. Sports medicine providers who work with high school football players need to realize that factors other than the type of protective equipment worn affect the risk of SRC in high school players. PMID:25060072

Vascular Health in American Football Players: Cardiovascular Risk Increased in Division III Players

Directory of Open Access Journals (Sweden)

Deborah L. Feairheller

2016-01-01

Full Text Available Studies report that football players have high blood pressure (BP and increased cardiovascular risk. There are over 70,000 NCAA football players and 450 Division III schools sponsor football programs, yet limited research exists on vascular health of athletes. This study aimed to compare vascular and cardiovascular health measures between football players and nonathlete controls. Twenty-three athletes and 19 nonathletes participated. Vascular health measures included flow-mediated dilation (FMD and carotid artery intima-media thickness (IMT. Cardiovascular measures included clinic and 24 hr BP levels, body composition, VO2 max, and fasting glucose/cholesterol levels. Compared to controls, football players had a worse vascular and cardiovascular profile. Football players had thicker carotid artery IMT (0.49 ± 0.06 mm versus 0.46 ± 0.07 mm and larger brachial artery diameter during FMD (4.3±0.5 mm versus 3.7±0.6 mm, but no difference in percent FMD. Systolic BP was significantly higher in football players at all measurements: resting (128.2±6.4 mmHg versus 122.4±6.8 mmHg, submaximal exercise (150.4±18.8 mmHg versus 137.3±9.5 mmHg, maximal exercise (211.3±25.9 mmHg versus 191.4±19.2 mmHg, and 24-hour BP (124.9±6.3 mmHg versus 109.8±3.7 mmHg. Football players also had higher fasting glucose (91.6±6.5 mg/dL versus 86.6±5.8 mg/dL, lower HDL (36.5±11.2 mg/dL versus 47.1±14.8 mg/dL, and higher body fat percentage (29.2±7.9% versus 23.2±7.0%. Division III collegiate football players remain an understudied population and may be at increased cardiovascular risk.

A Method for Using Player Tracking Data in Basketball to Learn Player Skills and Predict Team Performance.

Science.gov (United States)

Skinner, Brian; Guy, Stephen J

2015-01-01

Player tracking data represents a revolutionary new data source for basketball analysis, in which essentially every aspect of a player's performance is tracked and can be analyzed numerically. We suggest a way by which this data set, when coupled with a network-style model of the offense that relates players' skills to the team's success at running different plays, can be used to automatically learn players' skills and predict the performance of untested 5-man lineups in a way that accounts for the interaction between players' respective skill sets. After developing a general analysis procedure, we present as an example a specific implementation of our method using a simplified network model. While player tracking data is not yet available in the public domain, we evaluate our model using simulated data and show that player skills can be accurately inferred by a simple statistical inference scheme. Finally, we use the model to analyze games from the 2011 playoff series between the Memphis Grizzlies and the Oklahoma City Thunder and we show that, even with a very limited data set, the model can consistently describe a player's interactions with a given lineup based only on his performance with a different lineup.

Musculoskeletal injuries among Malaysian badminton players.

Science.gov (United States)

Shariff, A H; George, J; Ramlan, A A

2009-11-01

The purpose of this study was to investigate the pattern of musculoskeletal injuries sustained by Malaysian badminton players. This is a retrospective case notes review of all badminton players who attended the National Sports Institute (NSI) Clinic, Kuala Lumpur, Malaysia, and were diagnosed with musculoskeletal injuries. In a two and a half year period, from January 2005 to June 2007, 469 musculoskeletal injuries were diagnosed among badminton players at the NSI Clinic. The mean age of the players who attended the clinic was 19.2 (range 13-52) years. Approximately 60 percent of the injuries occurred in players younger than 20 years of age. The majority of injuries (91.5 percent) were categorised as mild overuse injury and mostly involved the knee. The majority of the injuries sustained by badminton players in this study were due to overuse, primarily in the knee. The majority of the injuries were diagnosed in younger players and occurred during training/practice sessions. There was no difference in terms of incidence and types of injuries between the genders.

Vitamin D Deficiency Among Professional Basketball Players.

Science.gov (United States)

Fishman, Matthew P; Lombardo, Stephen J; Kharrazi, F Daniel

2016-07-01

Vitamin D plays an important role in several systems of the human body. Various studies have linked vitamin D deficiency to stress and insufficiency fractures, muscle recovery and function, and athletic performance. The prevalence of vitamin D deficiency in the elite athletic population has not been extensively studied, and very few reports exist among professional athletes. There is a high prevalence of vitamin D deficiency or insufficiency among players attending the National Basketball Association (NBA) Combine. Cross-sectional study; Level of evidence, 3. This is a retrospective review of data previously collected as part of the routine medical evaluation of players in the NBA Combines from 2009 through 2013. Player parameters evaluated were height, weight, body mass index (BMI), and vitamin D level. Statistical analysis using t tests and analysis of variance was used to detect any correlation between the player parameters and vitamin D level. Vitamin D levels were categorized as deficient (32 ng/mL). After institutional review board approval was submitted to the NBA, the NBA released deidentified data on 279 players who participated in the combines from 2009 through 2013. There were 90 players (32.3%) who were deficient, 131 players (47.0%) who were insufficient, and 58 players (20.8%) who were sufficient. A total of 221 players (79.3%) were either vitamin D deficient or insufficient. Among all players included, the average vitamin D level was 25.6 ± 10.2 ng/mL. Among the players who were deficient, insufficient, and sufficient, the average vitamin D levels were 16.1 ± 2.1 ng/mL, 25.0 ± 3.4 ng/mL, and 41.6 ± 8.6 ng/mL, respectively. Player height and weight were significantly increased in vitamin D-sufficient players compared with players who were not sufficient (P = .0008 and .009, respectively). Player age and BMI did not significantly differ depending on vitamin D status (P = .15 and .77, respectively). There is a high prevalence of vitamin D deficiency

Time-motion analysis of goalball players in attacks: differences of the player positions and the throwing techniques.

Science.gov (United States)

Monezi, Lucas Antônio; Magalhães, Thiago Pinguelli; Morato, Márcio Pereira; Mercadante, Luciano Allegretti; Furtado, Otávio Luis Piva da Cunha; Misuta, Milton Shoiti

2018-03-26

In this study, we aimed to analyse goalball players time-motion variables (distance covered, time spent, maximum and average velocities) in official goalball match attacks, taking into account the attack phases (preparation and throwing), player position (centres and wings) and throwing techniques (frontal, spin and between the legs). A total of 365 attacks were assessed using a video based method (2D) through manual tracking using the Dvideo system. Inferential non-parametric statistics were applied for comparison of preparation vs. throwing phase, wings vs. centres and, among the throwing techniques, frontal, spin and between the legs. Significant differences were found between the attack preparation versus the throwing phase for all player time-motion variables: distance covered, time spent, maximum player velocity and average player velocity. Wing players performed most of the throws (85%) and covered longer distances than centres (1.65 vs 0.31 m). The between the legs and the spin throwing techniques presented greater values for most of the time-motion variables (distance covered, time spent and maximum player velocity) than did the frontal technique in both attack phases. These findings provide important information regarding players' movement patterns during goalball matches that can be used to plan more effective training.

A Method for Using Player Tracking Data in Basketball to Learn Player Skills and Predict Team Performance.

Directory of Open Access Journals (Sweden)

Brian Skinner

Full Text Available Player tracking data represents a revolutionary new data source for basketball analysis, in which essentially every aspect of a player's performance is tracked and can be analyzed numerically. We suggest a way by which this data set, when coupled with a network-style model of the offense that relates players' skills to the team's success at running different plays, can be used to automatically learn players' skills and predict the performance of untested 5-man lineups in a way that accounts for the interaction between players' respective skill sets. After developing a general analysis procedure, we present as an example a specific implementation of our method using a simplified network model. While player tracking data is not yet available in the public domain, we evaluate our model using simulated data and show that player skills can be accurately inferred by a simple statistical inference scheme. Finally, we use the model to analyze games from the 2011 playoff series between the Memphis Grizzlies and the Oklahoma City Thunder and we show that, even with a very limited data set, the model can consistently describe a player's interactions with a given lineup based only on his performance with a different lineup.

Finite stage asymmetric repeated games: Both players' viewpoints

KAUST Repository

Li, Lichun

2017-01-05

In asymmetric zero-sum games, one player has superior information about the game over the other. It is known that the informed players (maximizer) face the tradeoff of exploiting its superior information at the cost of revealing its superior information, but the basic point of the uninformed player (minimizer)\\'s decision making remains unknown. This paper studies the finite stage asymmetric repeated games from both players\\' viewpoints, and derives that not only security strategies but also the opponents\\' corresponding best responses depends only on the informed player\\'s history action sequences. Moreover, efficient LP formulations to compute both player\\'s security strategies are provided.

Shoulder instability in professional football players.

Science.gov (United States)

Leclere, Lance E; Asnis, Peter D; Griffith, Matthew H; Granito, David; Berkson, Eric M; Gill, Thomas J

2013-09-01

Shoulder instability is a common problem in American football players entering the National Football League (NFL). Treatment options include nonoperative and surgical stabilization. This study evaluated how the method of treatment of pre-NFL shoulder instability affects the rate of recurrence and the time elapsed until recurrence in players on 1 NFL team. Retrospective cohort. Medical records from 1980 to 2008 for 1 NFL team were reviewed. There were 328 players included in the study who started their career on the team and remained on the team for at least 2 years (mean, 3.9 years; range, 2-14 years). The history of instability prior to entering the NFL and the method of treatment were collected. Data on the occurrence of instability while in the NFL were recorded to determine the rate and timing of recurrence. Thirty-one players (9.5%) had a history of instability prior to entering the NFL. Of the 297 players with no history of instability, 39 (13.1%) had a primary event at a mean of 18.4 ± 22.2 months (range, 0-102 months) after joining the team. In the group of players with prior instability treated with surgical stabilization, there was no statistical difference in the rate of recurrence (10.5%) or the timing to the instability episode (mean, 26 months) compared with players with no history of instability. Twelve players had shoulder instability treated nonoperatively prior to the NFL. Five of these players (41.7%) had recurrent instability at a mean of 4.4 ± 7.0 months (range, 0-16 months). The patients treated nonoperatively had a significantly higher rate of recurrence (P = 0.02) and an earlier time of recurrence (P = 0.04). The rate of contralateral instability was 25.8%, occurring at a mean of 8.6 months. Recurrent shoulder instability is more common in NFL players with a history of nonoperative treatment. Surgical stabilization appears to restore the rate and timing of instability to that of players with no prior history of instability.

Purification and characterization of NADPH--cytochrome c reductase from the midgut of the southern armyworm (Spodoptera eridania).

Science.gov (United States)

Crankshaw, D L; Hetnarski, K; Wilkinson, C F

1979-09-01

1. NADPH-cytochrome c reductase was solubilized with bromelain and purified about 400-fold from sucrose/pyrophosphate-washed microsomal fractions from southern armyworm (Spodoptera eridania) larval midguts. 2. The enzyme has a mol.wt. of 70 035 +/- 1300 and contained 2 mol of flavin/mol of enzyme consisting of almost equimolar amounts of FMN and FAD. 3. Aerobic titration of the enzyme with NADPH caused the formation of a stable half-reduced state at 0.5 mol of NADPH/mol of flavin. 4. Kinetic analysis showed that the reduction of cytochrome c proceeded by a Bi Bi Ping Pong mechanism. 5. Apparent Km values for NADPH and cytochrome c and Ki values for NADP+ and 2'-AMP were considerably higher for the insect reductase than for the mammalian liver enzyme. 6. These are discussed in relation to possible differences in the active sites of the enzymes.

[Dietary behaviours of volleyball and basketball players].

Science.gov (United States)

Szczepańska, Elzbieta; Spałkowska, Agnieszka

2012-01-01

In sports, such as basketball and volleyball, players must demonstrate the speed, strength, stamina and concentration. Correct nutrition affects the strength of the muscles and the extension of capacity. It is also necessary for the proper functioning of the nervous system and determines the rate of regeneration after physical effort. The aim of this study was to assess dietary behaviours of professional volleyball and basketball players and compare the prevalence of correct behaviours in both groups. 209 professional volleyball and basketball players from sports clubs localized in six Silesian cities were survived with the mean of author questionnaire. The chi-square test was used to examine differences in the prevalence of the correct behaviours among players. Analysis of the results obtained showed that 52% of the players had 4-5 meals a day. 35% of respondents had wholemeal bread and/or groats daily. Milk and dairy products daily ate 71% of surveyed players, meat and sausages 70% respectively. 41% of respondents had cottage cheese and 28% had fish several times a week. Vegetables and fruit were eaten by 21% and respectively 23% of respondents. Sweets were eaten daily by 40% of surveyed, while fast-food were eaten several times a week by 17% of players. Nutrients for athletes were used by 32%, and vitamin supplementation by 48% of respondents. Prevalence of correct dietary behaviour in the group of professional volleyball and basketball players differed. Basketball players statistically more frequently than volleyball players had 4-5 meals a day, had wholemeal bread and/or thick groats, milk and dairy products, meat and sausages, especially poultry. They had raw vegetables and fruit several times a day. They drank more than 2.5 liters of fluids per day. They also significantly more frequently than volleyball players consumed the fast-food occasionally or never. Dietary behaviours of surveyed players were incorrect. Comparison of prevalence of proper behaviours

Chess players' fame versus their merit.

Science.gov (United States)

Simkin, M V; Roychowdhury, V P

2015-12-12

We investigate a pool of international chess title holders born between 1901 and 1943. Using Elo ratings, we compute for every player his expected score in a game with a randomly selected player from the pool. We use this figure as the player's merit. We measure players' fame as the number of Google hits. The correlation between fame and merit is 0.38. At the same time, the correlation between the logarithm of fame and merit is 0.61. This suggests that fame grows exponentially with merit.

Playing in School or at Home? An Exploration of the Effects of Context on Educational Game Experience

Science.gov (United States)

De Grove, Frederik; Van Looy, Jan; Neys, Joyce; Jansz, Jeroen

2012-01-01

The goal of this study is to gain insight into the effects of context on educational game experience. Using a quasi-experimental setup, it compares the playing and learning experiences of adolescent players of the awareness-raising game PING in a domestic (N=135) and a school (N=121) context. Results indicate that both gaming (identification,…

Racism in soccer? Perception of challenges of black and white players by white referees, soccer players, and fans.

Science.gov (United States)

Wagner-Egger, Pascal; Gygax, Pascal; Ribordy, Farfalla

2012-02-01

This experiment investigated challenge evaluations in soccer and their relation to prejudice: more precisely, whether skin colour may influence judgments of soccer tackles. Three groups of participants (soccer players, referees,and soccer fans) were asked to evaluate challenges, featuring Black and White players as aggressors and victims in a mixed-design study. Results showed that participants made some differentiations between Black and White players in a challenge evaluation task. Participants were more likely to consider within-group challenges as fouls and were faster to consider challenges made by Black players as fouls. On the other hand, fouls made by White players were seen as more severe. There were no major differences between the participating groups, suggesting that the observed effects were independent of how good players were or whether the participants were referees or not.

DIFFERENCES IN FUNCTIONAL AND MOTOR ABILITIES OFYOUNG FOOTBALL PLAYERS, BASKETBALL AND VOLLEYBALL PLAYERS

Directory of Open Access Journals (Sweden)

Franja Fratrić

2009-11-01

Full Text Available The main goal of this research is to determine whether and what differences exist between the three groups of subjects (high-quality football, volleyball and basketball cadets and youth age, in the motoric and functional abilities, as well as to identify dif- ferences between subgroups within each sport. The sample consists of 61 volleyball, 31 basketball player and football player 31 (total n = 123 male, cadet and youth age are members of local clubs. Subjects were born between 01.01.1991 and 12.12.1994. The sample of variables are the values of 17 tests for the evaluation of functional and mobile status. The Motor-functional status on the basis of the results of secondary value of foot- ball, basketball and volleyball make a clear conclusion that the football players showed the best results in almost all the tests and that they had the smallest disbalance in the power of certain groups of muscles.The football players hve the highest homogeneity.

Comparative characteristics of psychophysiological features skilled basketball players-women with hearing and skilled basketball players healthy

Directory of Open Access Journals (Sweden)

Kozina Zh.L.

2013-06-01

Full Text Available A comparative analysis of the psychophysiological features of skilled basketball players with normal hearing and impaired hearing aid. The study involved two women's basketball team to 12 people each. The study used a complex computer psychodiagnosis. The complex includes 20 psychophysiological and 18 personal psychological tests. The indicators of the time simple and complex reaction and average tapping test healthy skilled basketball players and basketball players are hearing impaired. There was a significant higher rates of visual-motor speed and reaction-tapping test in basketball players with hearing compared to healthy athletes. This is explained by compensatory mechanisms that occur in connection with the violation of the audition.

Comparative characteristics of psychophysiological features skilled basketball players-women with hearing and skilled basketball players healthy

Directory of Open Access Journals (Sweden)

Zh.L. Kozina

2013-07-01

Full Text Available A comparative analysis of the psychophysiological features of skilled basketball players with normal hearing and impaired hearing aid. The study involved two women's basketball team to 12 people each. The study used a complex computer psychodiagnosis. The complex includes 20 psychophysiological and 18 personal psychological tests. The indicators of the time simple and complex reaction and average tapping test healthy skilled basketball players and basketball players are hearing impaired. There was a significant higher rates of visual-motor speed and reaction-tapping test in basketball players with hearing compared to healthy athletes. This is explained by compensatory mechanisms that occur in connection with the violation of the audition.

The consultation of rugby players in co-developing a player health study: feasibility and consequences of sports participants as research partners.

Science.gov (United States)

Davies, Madeleine A M; Balai, Edward; Adams, Jo; Carter, John-Henry; Judge, Andrew; Newton, Julia L; Arden, Nigel K

2017-01-01

Many funding bodies within the United Kingdom and globally have encouraged public involvement in research. The Department of Health has also called public involvement a sign of good research. Despite the wide acceptance of public involvement improving many aspects of research, from its design to its communication, involvement has varied levels of implementation across different fields of research. Sports people have rarely been involved in research, partly as this research tends not to be funded by mainstream funding bodies. This may lead to a lower research quality, not founded in player ('service user') experiences. When creating a study of former rugby player health, we were very keen to involve rugby players, understand their thoughts on player health, and their playing experiences. This article explains how rugby players were involved in several ways, but mainly in group discussions during the design stage. These groups helped to inform our study's aims and questionnaire, ensure the questionnaire would capture player experiences and answer questions relevant to players, that they would like to understand after their participation in rugby. We found that these groups were easy to arrange, and that in only one session with each group, we were given many ideas of how to improve the questionnaire and study. We believe that other studies in sports should involve sports people, and that this is a useful activity that will change data collection forms and processes, improving the research, helping researchers, and making studies more suitable for players who take part in them. Background Patient and public involvement ('involvement') in the UK has increased in accordance with funding requirements, patient-centered health policy initiatives and reporting of the positive impact of involvement for those involved, research and researchers. However, involvement has not been implemented equally across all disease areas and populations. The aim of this process was to

Incidence of Stingers in Young Rugby Players.

Science.gov (United States)

Kawasaki, Takayuki; Ota, Chihiro; Yoneda, Takeshi; Maki, Nobukazu; Urayama, Shingo; Nagao, Masashi; Nagayama, Masataka; Kaketa, Takefumi; Takazawa, Yuji; Kaneko, Kazuo

2015-11-01

A stinger is a type of neurapraxia of the cervical roots or brachial plexus and represents a reversible peripheral nerve injury. The incidence of and major risk factors for stingers among young rugby players remain uninvestigated. To investigate the incidence, symptoms, and intrinsic risk factors for stingers in elite rugby union teams of young players. Descriptive epidemiology study. A total of 569 male rugby players, including 358 players from 7 high school teams and 211 players from 2 university teams, were investigated using self-administered preseason and postseason questionnaires. The prevalence of a history of stingers was 33.9% (95% CI, 30.3-37.9), and 20.9% (119/569) of players experienced at least 1 episode of a stinger during the season (34.2 [95% CI, 26.2-42.1] events per 1000 player-hours of match exposure). The reinjury rate for stingers per season was 37.3% (95% CI, 30.4-44.2). Using the multivariate Poisson regression method, a history of stingers in the previous season and the grade and position of the player were found to be risk factors for stingers during the current season. The mean severity of injury was 2.9 days, with 79.3% (191/241) of the players not losing any time from playing after sustaining a stinger injury and 5.8% (14/241) of the players recovering within more than 14 days. The most frequent symptom was numbness in the unilateral upper extremity, and the most severe symptom was weakness of grasping (mean severity, 6 days). A logistic regression analysis indicated that a history of stingers in the previous season and an injury with more than 3 symptoms, especially motor weakness, were correlated with the severity of injury. Young rugby players with a history of stingers have a significantly high rate of repeat injuries. Although nearly 80% of the players experienced only minimal (0-1 day) time loss injuries, neurological deficits sometimes last beyond 1 month. A history of stingers was identified to be the strongest risk factor for

Rules of engagement : influence of co-player presence on player involvement in digital games

NARCIS (Netherlands)

Gajadhar, B.J.; Kort, de Y.A.W.; IJsselsteijn, W.A.

2009-01-01

This article presents an empirical study of social setting as a determinant of player involvement in competitive play. We conceptualize player experience as comprising of components of involvement and enjoyment. Involvement relates to the attentional pull of games encompassing feelings of immersion,

An embouchure aid for saxophone player

Directory of Open Access Journals (Sweden)

Ho-Jin Moon

2012-02-01

Full Text Available This study aims to introduce the method that can relieve vibrating forces to oral environment by making an embouchure aid. Thin plastic crown forms were fabricated to prevent tooth abrasion and irritation to lip mucosa for the saxophone player. After application to the player, the most comfort form was chosen and delivered to 3 professional saxophone players. After 5 mon, the players responded to the survey. This embouchure aid did not disturb playing and gave comfort to lower lip. In general, the players preferred thin soft type and thought it caused little effect on sound. Far too little attention has been paid to the problems encountered by single-reed wind instrumentalist who suffer from tooth abrasion and irritation to lip mucosa. The embouchure aid not only prevent tooth damage but also diminish the discomfort of tight embouchure.

Auditory memory function in expert chess players.

Science.gov (United States)

Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

2015-01-01

Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert chess players using the Persian version of dichotic auditory-verbal memory test. The Persian version of dichotic auditory-verbal memory test was performed for 30 expert chess players aged 20-35 years and 30 non chess players who were matched by different conditions; the participants in both groups were randomly selected. The performance of the two groups was compared by independent samples t-test using SPSS version 21. The mean score of dichotic auditory-verbal memory test between the two groups, expert chess players and non-chess players, revealed a significant difference (p≤ 0.001). The difference between the ears scores for expert chess players (p= 0.023) and non-chess players (p= 0.013) was significant. Gender had no effect on the test results. Auditory memory function in expert chess players was significantly better compared to non-chess players. It seems that increased auditory memory function is related to strengthening cognitive performances due to playing chess for a long time.

Player Skill Decomposition in Multiplayer Online Battle Arenas

OpenAIRE

Chen, Zhengxing; Sun, Yizhou; El-nasr, Magy Seif; Nguyen, Truong-Huy D.

2017-01-01

Successful analysis of player skills in video games has important impacts on the process of enhancing player experience without undermining their continuous skill development. Moreover, player skill analysis becomes more intriguing in team-based video games because such form of study can help discover useful factors in effective team formation. In this paper, we consider the problem of skill decomposition in MOBA (MultiPlayer Online Battle Arena) games, with the goal to understand what player...

Expression of the Argonaute protein PiwiL2 and piRNAs in adult mouse mesenchymal stem cells

International Nuclear Information System (INIS)

Wu, Qiuling; Ma, Qi; Shehadeh, Lina A.; Wilson, Amber; Xia, Linghui; Yu, Hong; Webster, Keith A.

2010-01-01

Piwi (P-element-induced wimpy testis) first discovered in Drosophila is a member of the Argonaute family of micro-RNA binding proteins with essential roles in germ-cell development. The murine homologue of PiwiL2, also known as Mili is selectively expressed in the testes, and mice bearing targeted mutations of the PiwiL2 gene are male-sterile. PiwiL2 proteins are thought to protect the germ line genome by suppressing retrotransposons, stabilizing heterochromatin structure, and regulating target genes during meiosis and mitosis. Here, we report that PiwiL2 and associated piRNAs (piRs) may play similar roles in adult mouse mesenchymal stem cells. We found that PiwiL2 is expressed in the cytoplasm of metaphase mesenchymal stem cells from the bone marrow of adult and aged mice. Knockdown of PiwiL2 with a specific siRNA enhanced cell proliferation, significantly increased the number of cells in G1/S and G2/M cell cycle phases and was associated with increased expression of cell cycle genes CCND1, CDK8, microtubule regulation genes, and decreased expression of tumor suppressors Cables 1, LATS, and Cxxc4. The results suggest broader roles for Piwi in genome surveillance beyond the germ line and a possible role in regulating the cell cycle of mesenchymal stem cells.

Expression of the Argonaute protein PiwiL2 and piRNAs in adult mouse mesenchymal stem cells

Energy Technology Data Exchange (ETDEWEB)

Wu, Qiuling; Ma, Qi; Shehadeh, Lina A.; Wilson, Amber; Xia, Linghui; Yu, Hong [Department of Molecular and Cellular Pharmacology, Vascular Biology Institute, University of Miami Miller School of Medicine, Miami, FL 33136 (United States); Webster, Keith A., E-mail: kwebster@med.miami.edu [Department of Molecular and Cellular Pharmacology, Vascular Biology Institute, University of Miami Miller School of Medicine, Miami, FL 33136 (United States)

2010-06-11

Piwi (P-element-induced wimpy testis) first discovered in Drosophila is a member of the Argonaute family of micro-RNA binding proteins with essential roles in germ-cell development. The murine homologue of PiwiL2, also known as Mili is selectively expressed in the testes, and mice bearing targeted mutations of the PiwiL2 gene are male-sterile. PiwiL2 proteins are thought to protect the germ line genome by suppressing retrotransposons, stabilizing heterochromatin structure, and regulating target genes during meiosis and mitosis. Here, we report that PiwiL2 and associated piRNAs (piRs) may play similar roles in adult mouse mesenchymal stem cells. We found that PiwiL2 is expressed in the cytoplasm of metaphase mesenchymal stem cells from the bone marrow of adult and aged mice. Knockdown of PiwiL2 with a specific siRNA enhanced cell proliferation, significantly increased the number of cells in G1/S and G2/M cell cycle phases and was associated with increased expression of cell cycle genes CCND1, CDK8, microtubule regulation genes, and decreased expression of tumor suppressors Cables 1, LATS, and Cxxc4. The results suggest broader roles for Piwi in genome surveillance beyond the germ line and a possible role in regulating the cell cycle of mesenchymal stem cells.

Identification af explosive power factors as predictors of player quality in young female volleyball players.

Science.gov (United States)

Grgantov, Zoran; Milić, Mirjana; Katić, Ratko

2013-05-01

With the purpose of determining the factor structure of explosive power, as well as the influence of each factor on situational efficiency, 56 young female volleyball players were tested using 14 tests for assessing nonspecific and specific explosive power. By factor analysis, 4 significant factors were isolated which explained the total of over 80% of the common variability in young female volleyball players. The first factor was defined as volleyball-specific jumping, the second factor as nonspecific jumping and sprinting, the third factor as throwing explosive power, while the fourth factor was interpreted as volleyball-specific throwing and spiking speed from the ground. Results obtained by regression analysis in the latent space of explosive power indicate that the identified factors are good predictors of player quality in young female volleyball players. The fourth factor defined as throwing and spiking speed from the ground had the largest influence on player quality, followed by volleyball-specific jumping and nonspecific jumping and sprinting, and to a much lesser extent, by throwing explosive power The results obtained in this age group bring to the fore the ability of spiking and serving a ball of high speed, which hinders the opponents from playing those balls in serve reception and field defence. This ability, combined with a high standing vertical jump reach and spike approach vertical jump reach (which is the basis of the 1st varimax factor) enables successful performance of all volleyball elements by which points are won in complex 1 (spike) and complex 2 (serve and block). Even though the 2nd factor (nonspecific jumping and sprinting) has a slightly smaller impact on situational efficiency in young players, this ability provides preconditions i.e. preparation for successful realisation of all volleyball elements, so greater attention must be paid to perfecting it in young female volleyball players.

Protective equipment and player characteristics associated with the incidence of sport-related concussion in high school football players: a multifactorial prospective study.

Science.gov (United States)

McGuine, Timothy A; Hetzel, Scott; McCrea, Michael; Brooks, M Alison

2014-10-01

The incidence of sport-related concussion (SRC) in high school football is well documented. However, limited prospective data are available regarding how player characteristics and protective equipment affect the incidence of SRC. To determine whether the type of protective equipment (helmet and mouth guard) and player characteristics affect the incidence of SRC in high school football players. Cohort study; Level of evidence, 2. Certified athletic trainers (ATs) at each high school recorded the type of helmet worn (brand, model, purchase year, and recondition status) by each player as well as information regarding players' demographics, type of mouth guard used, and history of SRC. The ATs also recorded the incidence and days lost from participation for each SRC. Incidence of SRC was compared for various helmets, type of mouth guard, history of SRC, and player demographics. A total of 2081 players (grades 9-12) enrolled during the 2012 and/or 2013 football seasons (2287 player-seasons) and participated in 134,437 football (practice or competition) exposures. Of these players, 206 (9%) sustained a total of 211 SRCs (1.56/1000 exposures). There was no difference in the incidence of SRC (number of helmets, % SRC [95% CI]) for players wearing Riddell (1171, 9.1% [7.6%-11.0%]), Schutt (680, 8.7% [6.7%-11.1%]), or Xenith (436, 9.2% [6.7%-12.4%]) helmets. Helmet age and recondition status did not affect the incidence of SRC. The rate of SRC (hazard ratio [HR]) was higher in players who wore a custom mouth guard (HR = 1.69 [95% CI, 1.20-2.37], P football players. Players who had sustained an SRC within the previous 12 months were more likely to sustain an SRC than were players without a history of SRC. Sports medicine providers who work with high school football players need to realize that factors other than the type of protective equipment worn affect the risk of SRC in high school players. © 2014 The Author(s).

Executive Functioning in Highly Talented Soccer Players

Science.gov (United States)

Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap

2014-01-01

Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer. PMID:24632735

Executive functioning in highly talented soccer players.

Directory of Open Access Journals (Sweden)

Lot Verburgh

Full Text Available Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9, and forty-two age-matched amateur soccer players (mean age 11.8 in the age range 8 to 16 years performed a Stop Signal task (motor inhibition, the Attention Network Test (alerting, orienting, and executive attention and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer.

Comparison of Angiotensin Converting Enzyme (ACE gene polymorphisms elite basketball players and volleyball players

Directory of Open Access Journals (Sweden)

Emin Süel

2015-09-01

Full Text Available Aim: The purpose of this study is to research the differences of genotype polymorphism between the elite male and elite female basketball player, volleyball player and control group. Material and Methods: 58 basketball players (ages 24.25±4.99 years, height 188.22±12.31 cm and weight 80.62±16.34 kg, 64 volleyball players (ages 22.82±5.40 years, height 188.67±9.69 cm and weight 77.82±12.14 kg and 122 sedentary subjects (control group were participated randomly in the study. 5cc blood was taken control and control groups for measuring the ACE gene polymorphism. Chi-square and analysis of variance (ANOVA, Levene’s Tests, and frequencies of allele were used for statistical evaluation at significance level p0.05, basketball, volleyball and control group (p>0.05, male basketball, volleyball and control group (p>0.05, female basketball, volleyball and control group (p>0.05 and male and female athletes (p>0.05 respectively. There were no significance differences in male athletes between the genotype distribution and physical performance tests, such as 20m shuttle-run (F=1.31, vertical jump (F=0.22, and 20m sprint test (F=0.44. There were also no significance differences in female athletes between the genotype distribution and physical performance tests, such as 20m shuttle-run (F=2.03, vertical jump (F=0.10, and 20m sprint test (F=1.17. Conclusion: ACE polymorphism genotype distribution in terms of elite female and male volleyball players with elite female and male basketball players are the same.

Translucent Players: Explaining Cooperative Behavior in Social Dilemmas

Directory of Open Access Journals (Sweden)

Valerio Capraro

2016-06-01

Full Text Available In the last few decades, numerous experiments have shown that humans do not always behave so as to maximize their material payoff. Cooperative behavior when non-cooperation is a dominant strategy (with respect to the material payoffs is particularly puzzling. Here we propose a novel approach to explain cooperation, assuming what Halpern and Pass call translucent players. Typically, players are assumed to be opaque, in the sense that a deviation by one player in a normal-form game does not affect the strategies used by other players. But a player may believe that if he switches from one strategy to another, the fact that he chooses to switch may be visible to the other players. For example, if he chooses to defect in Prisoner's Dilemma, the other player may sense his guilt. We show that by assuming translucent players, we can recover many of the regularities observed in human behavior in well-studied games such as Prisoner's Dilemma, Traveler's Dilemma, Bertrand Competition, and the Public Goods game.

The audiological health of horn players.

Science.gov (United States)

Wilson, Wayne J; O'Brien, Ian; Bradley, Andrew P

2013-01-01

Among orchestral musicians, horn players are one of the most at-risk groups for noise-induced hearing loss (NIHL). To investigate this group further, pure tone audiometry and a 14-item questionnaire were used to assess the hearing health, as well as attitudes and practices regarding hearing conservation, among 142 French horn players attending an international horn conference in Brisbane, Australia. Of this study's French horn players, 11.1% to 22.2%, and 17.7% to 32.9% of those aged ≤40 years, showed some form of hearing loss (corrected for age and gender) typical of NIHL, using conservative versus lenient criteria, respectively. Stepwise multiple regression analyses showed no obvious predictor of hearing loss in this study's participants. Of the 18% of participants who reported using hearing protection, 81% used this protection "sometimes" and 50% used generic, foam, or other inferior forms of protection. Continued efforts to better manage the hearing health of horn players is warranted particularly as any hearing loss will affect a horn player's ability to perform and therefore his or her livelihood. Managing the hearing health of horn players will be challenging, however, with no simple predictor of NIHL loss being identified in this study's sample.

The Prevalence of Injuries in Professional Turkish Soccer Players

Science.gov (United States)

Yamaner, Faruk; Gumusdag, Hayrettin; Kartal, Alparslan; Gumus, M.; Gullu, A.; Imamoglu, O.

2011-01-01

Study aim: To assess the prevalence and anatomical sites of injuries in professional soccer players in one game season. Material and methods: A cohort of 510 professional male soccer players consisting of 48 goalkeepers, 194 defence players, 189 mid-field players and 79 forward players of the 1st and 2nd Turkish Professional Soccer Leagues in…

MiRNAs and piRNAs from bone marrow mesenchymal stem cell extracellular vesicles induce cell survival and inhibit cell differentiation of cord blood hematopoietic stem cells: a new insight in transplantation.

Science.gov (United States)

De Luca, Luciana; Trino, Stefania; Laurenzana, Ilaria; Simeon, Vittorio; Calice, Giovanni; Raimondo, Stefania; Podestà, Marina; Santodirocco, Michele; Di Mauro, Lazzaro; La Rocca, Francesco; Caivano, Antonella; Morano, Annalisa; Frassoni, Francesco; Cilloni, Daniela; Del Vecchio, Luigi; Musto, Pellegrino

2016-02-09

Hematopoietic stem cells (HSC), including umbilical cord blood CD34+ stem cells (UCB-CD34+), are used for the treatment of several diseases. Although different studies suggest that bone marrow mesenchymal stem cells (BM-MSC) support hematopoiesis, the exact mechanism remains unclear. Recently, extracellular vesicles (EVs) have been described as a novel avenue of cell communication, which may mediate BM-MSC effect on HSC. In this work, we studied the interaction between UCB-CD34+ cells and BM-MSC derived EVs. First, by sequencing EV derived miRNAs and piRNAs we found that EVs contain RNAs able to influence UCB-CD34+ cell fate. Accordingly, a gene expression profile of UCB-CD34+ cells treated with EVs, identified about 100 down-regulated genes among those targeted by EV-derived miRNAs and piRNAs (e.g. miR-27b/MPL, miR-21/ANXA1, miR-181/EGR2), indicating that EV content was able to modify gene expression profile of receiving cells. Moreover, we demonstrated that UCB-CD34+ cells, exposed to EVs, significantly changed different biological functions, becoming more viable and less differentiated. UCB-CD34+ gene expression profile also identified 103 up-regulated genes, most of them codifying for chemokines, cytokines and their receptors, involved in chemotaxis of different BM cells, an essential function of hematopoietic reconstitution. Finally, the exposure of UCB-CD34+ cells to EVs caused an increased expression CXCR4, paralleled by an in vivo augmented migration from peripheral blood to BM niche in NSG mice. This study demonstrates the existence of a powerful cross talk between BM-MSC and UCB-CD34+ cells, mediated by EVs, providing new insight in the biology of cord blood transplantation.

ANALYSIS AND COMPARISON OF ADOLESCENT ATHLETES' MOTIVATION: BASKETBALL PLAYERS VS. FOOTBALL PLAYERS

Directory of Open Access Journals (Sweden)

Bartolom\\u00E9 J. Almagro

2009-01-01

Full Text Available The motivation of an athlete is determinant for the athletic engagement of the adolescent. The present study attempts to analyze the motivation of adolescent basketball and football players from the perspectives of Achievement Goal Theory (Nicholls, 1989 and Self-Determination Theory (Deci & Ryan, 1985. The study's sample was composed of 248 athletes from 12 to 17 years of age. Half were from basketball and half were from football. The instruments that were utilized were: the Spanish version of the Sport Motivation Scale (SMS (Núñez, Martín-Albo, Navarro, & González, 2006, the Spanish version of the Perceived Motivational Climate in Sport Questionnaire-2 (PMSCQ-2 (Balaguer, Mayo, Atienza, & Duda, 1997, and the adapted Spanish translation (Moreno, Moreno, & Cervelló, 2007 of the Intention to be Physically Active Scale (IPAS by Hein, Müür, and Koka (2004. The comparison of the means of the variables between football and basketball players was done utilizing the student t-test for independent samples. Significant differences were found for variables such as: intrinsic motivation (IM toward accomplishment, external regulation, amotivation, task, ego, and Self-Determination Index (SDI. Basketball players obtained higher values in the SDI, in task, and in IM toward accomplishment than football players. The search for premature performance in football and coaches' educations can help to explain these differences. The importance of these differences reside in the relationship between these motivational variables and the adherence to athletic practice. In conclusion, basketball demonstrated better values in motivational variables, which demonstrates that training sessions are more oriented toward task than ego, that players have more intrinsic and self-determined motivation, and therefore, the adherence of the young athletes will be greater in this sport.

In quantum direct communication an undetectable eavesdropper can always tell Ψ from Φ Bell states in the message mode

Science.gov (United States)

Pavičić, Mladen

2013-04-01

We show that in any quantum direct communication protocol that is based on Ψ and Φ Bell states, an eavesdropper can always tell Ψ from Φ states without altering the transmission in any way in the message mode. This renders all protocols that make use of only one Ψ state and one Φ state completely insecure in the message mode. All four-Bell-state protocols require a revision and this might be of importance for new implementations of entanglement-based cryptographic protocols. The detection rate of an eavesdropper is 25% per control transmission, i.e., a half of the rate in the two-state (ping-pong) protocol. An eavesdropper can detect control probes with certainty in the standard control transmission without a photon in the Alice-to-Bob's travel mode and with near certainty in a transmission with a fake photon in the travel mode. Resending of measured control photons via the travel mode would make an eavesdropper completely invisible.

Mathematical modelling of the electrostatic pendulum in school and undergraduate education

International Nuclear Information System (INIS)

Forjan, Matej; Marhl, Marko; Grubelnik, Vladimir

2014-01-01

The electrostatic pendulum, also known as the electrostatic ping-pong, is an exciting experiment in school as well as in undergraduate education. We can easily demonstrate how the frequency of the electrostatic pendulum depends on the voltage across the capacitor. In this paper, we develop a simple mathematical model describing the dynamics of this experiment. In a step-wise manner, we introduce the external forces influencing the dynamics of the electrostatic pendulum. First, we take into account the electric force only. Then, we add air resistance and the non-elasticity of ball collisions with the capacitor plates. The model predictions show that the non-elastic collisions have greater effect on the pendulum dynamics than air resistance; in particular, this is true for higher frequencies of the pendulum. For lower frequencies, however, gravity is of crucial importance. The mathematical model is implemented in a graphic-oriented computer program, which gives the possibility of using this theoretical analysis also at the secondary school level. (paper)

Using Balls of Different Sports To Model the Variation of Atomic Sizes

Science.gov (United States)

Pinto, Gabriel

1998-06-01

In this article, an analogy is described about the order of magnitude of the variation of atomic sizes that can be used for discussion in introductory chemistry classes. The order of magnitude of this variation, involving microscopic magnitudes, is difficult for students to imagine. For the most part, the students are very familiar with the world of sports. In any case for example, the teacher can make use of the wide, informative coverage given to the olympic games or similar events, where different sports are televised in a few days. The radii of official balls for seven well-known sports are given, and students must assign an atom to each ball by using tabulated single-bond, covalent radii and by assigning the smallest ball (i.e., corresponding to ping-pong) to the smallest atom (i.e., hydrogen). The balls can also be used to show how the ionic radii change upon ionization.

Some experiments on the primary electron acceptor in reaction centres from Rhodopseudomanas sphaeroides

Energy Technology Data Exchange (ETDEWEB)

Wraight, C A; Cogdell, R J; Clayton, R K

1975-01-01

The bacterial reaction center absorbance change at 450 nm (A-450), assigned to an anionic semiquinone, has been suggested as a candidate for the reduced form of the primary electron acceptor in bacterial photosynthesis. In reaction centers of Rhodopseudomonas sphaeroides we have found kinetic discrepancies between the decay of A-450 and the recovery of photochemical competence. In addition, no proton uptake is measurable on the first turnover, although subsequent ones elicit one proton bound per electron. These results are taken to indicate that the acceptor reaction after a long dark period may be different for the first turnover than for subsequent ones. It is suggested that A-450 is still a likely candidate for the acceptor function but that in reaction centers, additional quinone may act as an adventitious primary acceptor when the ''true'' primary acceptor is reduced. Alternatively, the primary acceptor may act in a ''ping-pong'' fashion with respect to subsequent photoelectrons.

Modeling of an immobilized lipase tubular reactor for the production of glycerol and fatty acids from oils; Modelado de un reactor tubular de lipasas inmovilizadas para la produccion de glicerol y acidos grasos a partir de aceites

Energy Technology Data Exchange (ETDEWEB)

Oddone, S.; Grasselli, M.; Cuellas, A.

2010-07-01

Advances in the design of a bioreactor in the fats and oils industry have permitted the hydrolysis of triglycerides in mild conditions and improved productivity while avoiding the formation of unwanted byproducts. The present work develops a mathematical model that describes the hydrolytic activity of a tubular reactor with immobilized lipases for the production of glycerol and fatty acids from the oil trade. Runge Kuttas numerical method of high order has been applied, considering that there is no accumulation of the substratum in the surface of the membrane, where the enzyme is. At the same time, different equations based on the kinetic model of Michaelis Mentens and the Ping-Pong bi-bi mechanism were examined. Experimental data in discontinuous systems are the basis for the development of the quantitative mathematical model that was used to simulate the process computationally. The obtained results allow for optimizing both the operative variables and the economic aspects of industrial processes. (Author)

Kinetics of the H 2O 2-dependent ligninase-catalyzed oxidation of veratryl alcohol in the presence of cationic surfactant studied by spectrophotometric technique

Science.gov (United States)

Liu, Airong; Huang, Xirong; Song, Shaofang; Wang, Dan; Lu, Xuemei; Qu, Yinbo; Gao, Peiji

2003-09-01

The kinetics of ligninase-catalyzed oxidation of veratryl alcohol (VA) by H 2O 2 in the aqueous medium containing cationic surfactant cetyltrimethylammonium bromide (CTAB) has been investigated using spectrophotometric technique. Steady-state kinetic studies at different concentrations of CTAB indicate that the reaction follows a ping pong mechanism and the mechanism always holds but the kinetic parameters vary with CTAB concentrations. CTAB is a weak inhibitor for ligninase; it lowers the maximum initial velocity. CTAB also causes the Michaelis constant of H 2O 2 to decrease dramatically and that of VA to increase markedly. Based on the changes in kinetic parameters of the enzyme-catalyzed reaction at different CTAB concentrations (lower than, near to and larger than its critical micelle concentration) and the effects of the CTAB monomer and the micelles on the spectra of VA and its corresponding aldehyde, a conclusion could be made that modification of the enzymatic protein by the surfactant monomer should be responsible for the above-mentioned results.

New insights into the catalytic mechanism of human glycine N-acyltransferase.

Science.gov (United States)

van der Sluis, Rencia; Ungerer, Vida; Nortje, Carla; A van Dijk, Alberdina; Erasmus, Elardus

2017-11-01

Even though the glycine conjugation pathway was one of the first metabolic pathways to be discovered, this pathway remains very poorly characterized. The bi-substrate kinetic parameters of a recombinant human glycine N-acyltransferase (GLYAT, E.C. 2.3.1.13) were determined using the traditional colorimetric method and a newly developed HPLC-ESI-MS/MS method. Previous studies analyzing the kinetic parameters of GLYAT, indicated a random Bi-Bi and/or ping-pong mechanism. In this study, the hippuric acid concentrations produced by the GLYAT enzyme reaction were analyzed using the allosteric sigmoidal enzyme kinetic module. Analyses of the initial rate (v) against substrate concentration plots, produced a sigmoidal curve (substrate activation) when the benzoyl-CoA concentrations was kept constant, whereas the plot with glycine concentrations kept constant, passed through a maximum (substrate inhibition). Thus, human GLYAT exhibits mechanistic kinetic cooperativity as described by the Ferdinand enzyme mechanism rather than the previously assumed Michaelis-Menten reaction mechanism. © 2017 Wiley Periodicals, Inc.

A quantum secure direct communication protocol based on a five-particle cluster state and classical XOR operation

International Nuclear Information System (INIS)

Li Jian; Song Danjie; Guo Xiaojing; Jing Bo

2012-01-01

In order to transmit secure messages, a quantum secure direct communication protocol based on a five-particle cluster state and classical XOR operation is presented. The five-particle cluster state is used to detect eavesdroppers, and the classical XOR operation serving as a one-time-pad is used to ensure the security of the protocol. In the security analysis, the entropy theory method is introduced, and three detection strategies are compared quantitatively by using the constraint between the information that the eavesdroppers can obtain and the interference introduced. If the eavesdroppers intend to obtain all the information, the detection rate of the original ping-pong protocol is 50%; the second protocol, using two particles of the Einstein-Podolsky-Rosen pair as detection particles, is also 50%; while the presented protocol is 89%. Finally, the security of the proposed protocol is discussed, and the analysis results indicate that the protocol in this paper is more secure than the other two. (authors)

N-player quantum games in an EPR setting.

Directory of Open Access Journals (Sweden)

James M Chappell

Full Text Available The N-player quantum games are analyzed that use an Einstein-Podolsky-Rosen (EPR experiment, as the underlying physical setup. In this setup, a player's strategies are not unitary transformations as in alternate quantum game-theoretic frameworks, but a classical choice between two directions along which spin or polarization measurements are made. The players' strategies thus remain identical to their strategies in the mixed-strategy version of the classical game. In the EPR setting the quantum game reduces itself to the corresponding classical game when the shared quantum state reaches zero entanglement. We find the relations for the probability distribution for N-qubit GHZ and W-type states, subject to general measurement directions, from which the expressions for the players' payoffs and mixed Nash equilibrium are determined. Players' N x N payoff matrices are then defined using linear functions so that common two-player games can be easily extended to the N-player case and permit analytic expressions for the Nash equilibrium. As a specific example, we solve the Prisoners' Dilemma game for general N ≥ 2. We find a new property for the game that for an even number of players the payoffs at the Nash equilibrium are equal, whereas for an odd number of players the cooperating players receive higher payoffs. By dispensing with the standard unitary transformations on state vectors in Hilbert space and using instead rotors and multivectors, based on Clifford's geometric algebra (GA, it is shown how the N-player case becomes tractable. The new mathematical approach presented here has wide implications in the areas of quantum information and quantum complexity, as it opens up a powerful way to tractably analyze N-partite qubit interactions.

Player Modeling for Intelligent Difficulty Adjustment

Science.gov (United States)

Missura, Olana; Gärtner, Thomas

In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.

Secure Multi-Player Protocols

DEFF Research Database (Denmark)

Fehr, Serge

While classically cryptography is concerned with the problem of private communication among two entities, say players, in modern cryptography multi-player protocols play an important role. And among these, it is probably fair to say that secret sharing, and its stronger version verifiable secret...... sharing (VSS), as well as multi-party computation (MPC) belong to the most appealing and/or useful ones. The former two are basic tools to achieve better robustness of cryptographic schemes against malfunction or misuse by “decentralizing” the security from one single to a whole group of individuals...... (captured by the term threshold cryptography). The latter allows—at least in principle—to execute any collaboration among a group of players in a secure way that guarantees the correctness of the outcome but simultaneously respects the privacy of the participants. In this work, we study three aspects...

Comparison of Shoulder Strength in Routinely Trained Badminton Players and Non-Badminton Players

Directory of Open Access Journals (Sweden)

Wong Zhen Feng

2017-06-01

Full Text Available Background: Shoulder pain is a common reason for patients to seek medical help in any healthcare center. Shoulder pain is influenced by a few factors such as gender, posture during daily activities, aging and psychological factors. Based on the study of Epidemiology of Injuries and Prevention Strategies in Competitive Swimmers, shoulder pain due to shoulder injuries can be reduced by strengthening the shoulder muscle. Badminton has become one of the most popular sports in Asia, especially in Indonesia. This study was conducted to determine if badmintonis able to strengthen the shoulder muscle group. Methods: A cross-sectional analytic experimental study was conducted on September 2015 at Lodaya Badminton Training Center and Bale Padjadjaran of Universitas Padjadjaran. Subjects were 30 healthy male routinely trained badminton players and 30 non-badminton players who voluntarily follow the rstudy procedures. Strength measurement procedures were provided to the subjects after getting informed consent.  Data analysis was performed using T-test. Results: The shoulder strength  in routinely trained badminton players was significantly different from  non-badminton players (P<0.05. Conclusions: Shoulder strength can be improved through routine training of badminton to reduce risk of shoulder injury.   DOI: 10.15850/amj.v4n2.1083

How Players Lose Interest in Playing a Game

DEFF Research Database (Denmark)

Bauckhage, Christian; Kersting, Kristian; Sifa, Rafet

2012-01-01

introduce methods from random process theory into game data mining in order to draw inferences about player engagement. Given large samples (over 250,000 players) of behavioral telemetry data from five different action-adventure and shooter games, we extract information as to how long individual players......Analyzing telemetry data of player behavior in computer games is a topic of increasing interest for industry and research, alike. When applied to game telemetry data, pattern recognition and statistical analysis provide valuable business intelligence tools for game development. An important problem...... in this area is to characterize how player engagement in a game evolves over time. Reliable models are of pivotal interest since they allow for assessing the long-term success of game products and can provide estimates of how long players may be expected to keep actively playing a game. In this paper, we...

Effect of coach change on professional tennis players

OpenAIRE

Nekolová, Barbora

2014-01-01

Title: Effect of coach change on professional tennis players Objectives of work: The aim of the thesis is to analyze the impact of coach change on professional tennis players from the psychology perspective, social relationship and player's attitude to the sport itself. The impact of the coach change on player's approach to tennis, game results, personal life and interpersonal relationships will be examined. Method: The methods that will be used are narrative interviews - annotated transcript...

Bridging Media with the Help of Players

Science.gov (United States)

Nitsche, Michael; Drake, Matthew; Murray, Janet

We suggest harvesting the power of multiplayer design to bridge content across different media platforms and develop player-driven cross-media experiences. This paper first argues to partially replace complex AI systems with multiplayer design strategies to provide the necessary level of flexibility in the content generation for cross-media applications. The second part describes one example project - the Next Generation Play (NGP) project - that illustrates one practical approach of such a player-driven cross-media content generation. NGP allows players to collect virtual items while watching a TV show. These items are re-used in a multiplayer casual game that automatically generates new game worlds based on the various collections of active players joining a game session. While the TV experience is designed for the single big screen, the game executes on multiple mobile phones. Design and technical implementation of the prototype are explained in more detail to clarify how players carry elements of television narratives into a non-linear handheld gaming experience. The system describes a practical way to create casual game adaptations based on players' personal preferences in a multi-user environment.

Vitamin D profile in National Football League players.

Science.gov (United States)

Maroon, Joseph C; Mathyssek, Christina M; Bost, Jeffrey W; Amos, Austin; Winkelman, Robert; Yates, Anthony P; Duca, Mark A; Norwig, John A

2015-05-01

By maintaining phosphate and calcium homeostasis, vitamin D is critical for bone health and possibly physical performance. Hence, vitamin D is important to athletes. Few studies have investigated vitamin D levels in relation to fractures and performance in athletes, and no published study has included a multiracial sample of professional American football players. To assess vitamin D levels, including the prevalence of vitamin D deficiency/insufficiency, in professional American football players and to evaluate the association of vitamin D levels with race, fracture history, and the ability to obtain a contract position, which may be a marker for athletic performance. Cohort study; Level of evidence, 3. Serum vitamin D levels of 80 professional football players from a single team in the National Football League were obtained during the 2011 off-season (mean age, 26.5±3.7 years; black, n=67 [84%]). These levels were used to compare injury reports from the 2011-2012 and 2012-2013 seasons. Statistical analyses were performed to test if vitamin D levels were related to race, fracture history, and the ability to obtain a contract position. Mean vitamin D level was 27.4±11.7 ng/mL, with significantly lower levels for black players (25.6±11.3 ng/mL) versus white players (37.4±8.6 ng/mL; F 1,78=13.00, P=.001). All athletes who were vitamin D deficient were black. When controlling for number of professional years played, vitamin D levels were significantly lower in players with at least 1 bone fracture when compared with no fractures. Players who were released during the preseason because of either injury or poor performance had significantly lower vitamin D levels than did players who played in the regular season. Black professional football players have a higher rate of vitamin D deficiency than do white players. Furthermore, professional football players with higher vitamin D levels were more likely to obtain a contract position in the National Football League

Outcomes of microfracture in professional basketball players.

Science.gov (United States)

Cerynik, Douglas L; Lewullis, Gabriel E; Joves, Brian C; Palmer, Michael P; Tom, James A

2009-09-01

Surgical treatment for chondral defects of the knee in competitive running and jumping athletes remains controversial. This study evaluated the performance outcomes of professional basketball players in the National Basketball Association (NBA) who underwent microfracture. Data from 24 professional basketball players from 1997 to 2006 was obtained and analyzed. NBA player efficiency ratings (PER) were calculated for two seasons before and after injury. A control group of 24 players was used for comparison. Study group and control group demographics including age, NBA experience, and minutes per game demonstrated no statistical difference. Mean time to return to an NBA game was 30.0 weeks from the time of surgery. The first season after returning to competition PER and minutes per game decreased by 3.5 (P 0.05) and 3.0 min (P NBA game. On return to competition player performance and minutes per game are diminished.

Injuries in Spanish female soccer players

Directory of Open Access Journals (Sweden)

Juan Del Coso

2018-04-01

Full Text Available Background: Epidemiologic research to learn the incidence, type, location, and severity of female soccer injuries and the risk factors for sustaining a sport injury is the first step in developing preventive policies. The aim of this study was to analyze the incidence of injuries in the population of female soccer players in Spain. Methods: The injuries incurred by 25,397 female soccer players were registered by the medical staff of the Spanish Football Federation during 1 season. A standardized medical questionnaire was used to classify the injury according to type, severity, location, and injury mechanism. A total of 2108 injuries was reported with an incidence of 0.083 injuries per player per season. Most injuries were in the lower limbs (74.0%, mainly affecting knee (30.4% and ankle joints (17.9%. Results: The proportion of injuries derived from contact with another player was higher during matches (33.7% than during training (11.4%; p  0.05. Conclusion: Most female soccer injuries were located at the knee and ankle; the injury mechanism determined the playing time lost; and the player's age did not affect injury characteristics. Keywords: Ankle, Epidemiology, Knee, Sport injuries, Women

Gender-specific hierarchy in nuage localization of PIWI-interacting RNA factors in Drosophila

Directory of Open Access Journals (Sweden)

Mikiko C Siomi

2011-08-01

Full Text Available PIWI-interacting RNAs (piRNAs are germline-specific small non-coding RNAs that form piRNA-induced silencing complexes (piRISCs by associating with PIWI proteins, a subclade of the Argonaute proteins predominantly expressed in the germline. piRISCs protect the integrity of the germline genome from invasive transposable DNA elements by silencing them. Multiple piRNA biogenesis factors have been identified in Drosophila. The majority of piRNA factors are localized in the nuage, electron-dense non-membranous cytoplasmic structures located in the perinuclear regions of germ cells. Thus, piRNA biogenesis is thought to occur in the nuage in germ cells. Immunofluorescence analyses of ovaries from piRNA factor mutants have revealed a localization hierarchy of piRNA factors in female nuage. However, whether this hierarchy is female-specific or can also be applied in male gonads remains undetermined. Here, we show by immunostaining of both ovaries and testes from piRNA factor mutants that the molecular hierarchy of piRNA factors shows gender-specificity, especially for Krimper (Krimp, a Tudor-domain containing protein of unknown function(s: Krimp is dispensable for PIWI protein Aubergine (Aub nuage localization in ovaries but Krimp and Aub require each other for their proper nuage localization in testes. This suggests that the functional requirement of Krimp in piRNA biogenesis may be different in male and female gonads.

Towards Player-Driven Procedural Content Generation

DEFF Research Database (Denmark)

Shaker, Noor; Yannakakis, Georgios N.; Togelius, Julian

2012-01-01

Generating immersive game content is one of the ultimate goals for a game designer. This goal can be achieved by realizing the fact that players’ perception of the same game differ according to a number of factors including: players’ personality, playing styles, expertise and culture background....... While one player might find the game immersive, others may quit playing as a result of encountering a seemingly insoluble problem. One promising avenue towards optimizing the gameplay experience for individual game players is to tailor player experience in real-time via automatic game content generation......-driven content generation....

Sex-specific differences in injury types among basketball players.

Science.gov (United States)

Ito, Eri; Iwamoto, Jun; Azuma, Koichiro; Matsumoto, Hideo

2015-01-01

The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females) were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%), and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%). The proportion of anterior cruciate ligament injury in the 10-19-year-old age group was higher among female players than among male players (45.9% vs 22.1%), while the proportions of Osgood-Schlatter disease in the 10-19-year-old age group and jumper's knee (patellar and femoral tendinopathy) in the 20-29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively). However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.

Drosophila interspecific hybrids phenocopy piRNA-pathway mutants.

Directory of Open Access Journals (Sweden)

Erin S Kelleher

Full Text Available The Piwi-interacting RNA (piRNA pathway defends the germline of animals from the deleterious activity of selfish transposable elements (TEs through small-RNA mediated silencing. Adaptation to novel invasive TEs is proposed to occur by incorporating their sequences into the piRNA pool that females produce and deposit into their eggs, which then propagates immunity against specific TEs to future generations. In support of this model, the F1 offspring of crosses between strains of the same Drosophila species sometimes suffer from germline derepression of paternally inherited TE families, caused by a failure of the maternal strain to produce the piRNAs necessary for their regulation. However, many protein components of the Drosophila piRNA pathway exhibit signatures of positive selection, suggesting that they also contribute to the evolution of host genome defense. Here we investigate piRNA pathway function and TE regulation in the F1 hybrids of interspecific crosses between D. melanogaster and D. simulans and compare them with intraspecific control crosses of D. melanogaster. We confirm previous reports showing that intraspecific crosses are characterized by derepression of paternally inherited TE families that are rare or absent from the maternal genome and piRNA pool, consistent with the role of maternally deposited piRNAs in shaping TE silencing. In contrast to the intraspecific cross, we discover that interspecific hybrids are characterized by widespread derepression of both maternally and paternally inherited TE families. Furthermore, the pattern of derepression of TE families in interspecific hybrids cannot be attributed to their paucity or absence from the piRNA pool of the maternal species. Rather, we demonstrate that interspecific hybrids closely resemble piRNA effector-protein mutants in both TE misregulation and aberrant piRNA production. We suggest that TE derepression in interspecific hybrids largely reflects adaptive divergence of piRNA

The El Dorado of Handball? Foreign Female Players Stay, while Domestic Players Return from Abroad

Science.gov (United States)

Topič, Mojca Doupona; Šibila, Marko

2016-01-01

Abstract The main purpose of this research was to study the characteristics of migration in European women’s handball based on the Slovenian example and to find the differences between the foreigners coming to Slovenia and the Slovenians transferring to foreign clubs. The research was based on 16 open face-to-face semi-structured interviews (8 Slovenians (age 29.5 ± 6.2 years) and 8 foreigners (age 35.5 ± 8.7 years)). We found out that the most powerful factor in foreigners was the financial one, while within Slovenian players it was their personal desire for progression within their sport, the club’s reputation and poor conditions in their previous club. The results confirm that when making a decision on transfer, all players had the support of family and friends, while the clubs of foreign players were not as supportive. Most interviewees considered their careers successful and did not regret going abroad. The research indicates that the largest differences discovered between Slovenians and foreigners were that foreign female players chose to stay in the new country (Slovenia), while domestic players returned home after few years playing abroad. In conclusion, the results show that in top-level handball there are important differences between migration models which are based on nationality and also that the migration models change throughout time, which is largely connected with the socioeconomic events in the country of origin or transfer. PMID:28149349

The El Dorado of Handball? Foreign Female Players Stay, while Domestic Players Return from Abroad

Directory of Open Access Journals (Sweden)

Bon Marta

2016-04-01

Full Text Available The main purpose of this research was to study the characteristics of migration in European women’s handball based on the Slovenian example and to find the differences between the foreigners coming to Slovenia and the Slovenians transferring to foreign clubs. The research was based on 16 open face-to-face semi-structured interviews (8 Slovenians (age 29.5 ± 6.2 years and 8 foreigners (age 35.5 ± 8.7 years. We found out that the most powerful factor in foreigners was the financial one, while within Slovenian players it was their personal desire for progression within their sport, the club’s reputation and poor conditions in their previous club. The results confirm that when making a decision on transfer, all players had the support of family and friends, while the clubs of foreign players were not as supportive. Most interviewees considered their careers successful and did not regret going abroad. The research indicates that the largest differences discovered between Slovenians and foreigners were that foreign female players chose to stay in the new country (Slovenia, while domestic players returned home after few years playing abroad. In conclusion, the results show that in top-level handball there are important differences between migration models which are based on nationality and also that the migration models change throughout time, which is largely connected with the socioeconomic events in the country of origin or transfer.

Efficiently detecting outlying behavior in video-game players.

Science.gov (United States)

Kim, Young Bin; Kang, Shin Jin; Lee, Sang Hyeok; Jung, Jang Young; Kam, Hyeong Ryeol; Lee, Jung; Kim, Young Sun; Lee, Joonsoo; Kim, Chang Hun

2015-01-01

In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players' characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse) was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.

Head Impact Exposure in Junior and Adult Australian Football Players

Directory of Open Access Journals (Sweden)

Mark Hecimovich

2018-01-01

Full Text Available This study measured and compared the frequency, magnitude, and distribution of head impacts sustained by junior and adult Australian football players, respectively, and between player positions over a season of games. Twelve junior and twelve adult players were tracked using a skin-mounted impact sensor. Head impact exposure, including frequency, magnitude, and location of impacts, was quantified using previously established methods. Over the collection period, there were no significant differences in the impact frequency between junior and adult players. However, there was a significant increase in the frequency of head impacts for midfielders in both grades once we accounted for player position. A comparable amount of head impacts in both junior and adult players has implications for Australian football regarding player safety and medical coverage as younger players sustained similar impact levels as adult players. The other implication of a higher impact profile within midfielders is that, by targeting education and prevention strategies, a decrease in the incidence of sports-related concussion may result.

Morphological evolution of Springbok rugby players: Implications for ...

African Journals Online (AJOL)

The physique of rugby players has evolved over the course of the Twentieth Century. A novel morphological dataset was constructed of all Springbok rugby players until 2014. Although most of the change in body structure, particularly body weight, occurs during the era of professionalism, white Springbok rugby players ...

Hip Arthroscopy in High-Level Baseball Players.

Science.gov (United States)

Byrd, J W Thomas; Jones, Kay S

2015-08-01

To report the results of hip arthroscopy among high-level baseball players as recorded by outcome scores and return to baseball. All patients undergoing hip arthroscopy were prospectively assessed with the modified Harris Hip Score. On review of all procedures performed over a 12-year period, 44 hips were identified among 41 intercollegiate or professional baseball players who had achieved 2-year follow-up. Among the 41 players, follow-up averaged 45 months (range, 24 to 120 months), with a mean age of 23 years (range, 18 to 34 years). There were 23 collegiate (1 bilateral) and 18 professional (2 bilateral) baseball players, including 10 Major League Baseball players. Of the 8 Major League Baseball pitchers, 6 (75%) also underwent ulnar collateral ligament elbow surgery. Improvement in the modified Harris Hip Score averaged 13 points (from 81 points preoperatively to 94 points postoperatively); a paired-samples t test determined that this mean improvement of 13 points was statistically significant (P arthroscopy. This study supports the idea that arthroscopic treatment for a variety of hip pathologies in high-level baseball players provides a successful return to sport and improvement in functional outcome scores. Level IV, therapeutic case series. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Football players, asset management & the unexploited potential of enhanced player engagement in football management & marketing

DEFF Research Database (Denmark)

Cortsen, Kenneth

2016-01-01

This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives.......This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives....

Football players, asset management & the unexploited potential of enhanced player engagement in football management & marketing

DEFF Research Database (Denmark)

Cortsen, Kenneth

2014-01-01

This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives.......This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives....

High School Rugby Players' Perception of Coaching Effectiveness

Science.gov (United States)

Broodryk, Retief; van den Berg, Pieter Hendrick

2011-01-01

The aims of this study were firstly to determine the players' perceptions of their respective coaches' coaching effectiveness and secondly, determine the difference between big and small schools of the players' perceptions of their respective coaches' coaching effectiveness. Four hundred and seventy six players from 22 schools were asked to fill…

Swimming literacy field hockey woman player ground.

OpenAIRE

Baštová, Miroslava

2012-01-01

Title: Swimming literacy field hockey woman player ground. Objectives: To obtain and analyze data on the level ground swimming literacy field hockey woman player. Their perception swimming literacy for life, the use of non-specific regeneration and as a training resource. Methods: Analysis of scientific literature, survey, case study, data analysis and graphical presentation of results. Results of the work: field hockey player as swimming literate, benefits swimming but not used as a means of...

Protective equipment use among female rugby players.

Science.gov (United States)

Comstock, R Dawn; Fields, Sarah K; Knox, Christy L

2005-07-01

Our objective was to assess the prevalence of protective equipment use and the motivation for using protective equipment among a sample of US female rugby players. We surveyed a convenience sample of 234 current US female rugby players from 14 teams participating in a US women's rugby tournament, obtaining self-reported demographic, rugby exposure, and protective equipment use information. Mouthguards were the most commonly used piece of protective equipment: 90.8% of players reported having always worn a mouthguard while playing or practicing rugby within their most recent 3 months of play. Fewer than 15% of players reported having always worn other types of protective equipment. Equipment use varied by playing position. Whereas over 80% of players in all other positions always wore a mouthguard, 66.7% of scrum halves reported always wearing one. Both backs and forwards reported wearing shoulder pads, but only forwards reported always wearing padded headgear. Mouthguards, padded headgear, and shoulder pads were worn "to prevent injury," whereas ankle braces, neoprene sleeves, and athletic tape on joints were worn "to protect a current/recent injury." This is the first study of female rugby players to assess the prevalence of protective equipment use by playing position and the motivation for using protective equipment. With the exception of mouthguards, US female rugby players infrequently use protective equipment. Protective equipment use varies by playing position. Some types of protective equipment appear to be used as primary prevention mechanisms, whereas others are used as secondary or tertiary prevention mechanisms.

Sex-specific differences in injury types among basketball players

Directory of Open Access Journals (Sweden)

Ito E

2014-12-01

Full Text Available Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%, and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%. The proportion of anterior cruciate ligament injury in the 10–19-year-old age group was higher among female players than among male players (45.9% vs 22.1%, while the proportions of Osgood–Schlatter disease in the 10–19-year-old age group and jumper's knee (patellar and femoral tendinopathy in the 20–29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively. However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.Keywords: sports injury, sex, anterior cruciate ligament injury, Osgood–Schlatter disease, basketball

Strength asymmetry of the shoulders in elite volleyball players.

Science.gov (United States)

Hadzic, Vedran; Sattler, Tine; Veselko, Matjaž; Markovic, Goran; Dervisevic, Edvin

2014-01-01

Volleyball players are reported to have shoulder strength imbalances. Previous authors have primarily investigated small samples of male players at a single skill level, without considering playing position, and with inconsistent findings. To evaluate shoulder strength asymmetry and a history of shoulder injury in a large sample of professional volleyball players of both sexes across different playing positions and skill levels. Descriptive laboratory study. A sample of 183 volleyball players (99 men, 84 women). We assessed shoulder internal-rotator and external-rotator concentric strength at 60°/s using an isokinetic dynamometer and dominant-nondominant differences in shoulder strength and strength ratios using repeated-measures analyses of variance. Peak torque was normalized for body mass and external-rotation/internal-rotation concentric strength. Internal-rotation strength was asymmetric in favor of the dominant side in both sexes, regardless of previous shoulder injury status. Male volleyball players had a lower shoulder strength ratio on the dominant side, regardless of previous shoulder injury status. However, this finding was valid only when hand dominance was taken into account. Female volleyball players playing at a higher level (ie, first versus second division) were 3.43 times more likely to have an abnormal strength ratio. Playing position was not associated with an abnormal shoulder strength ratio or strength asymmetry. In male volleyball players, the external-rotation/internal-rotation strength ratio of the dominant shoulder was lower, regardless of playing position, skill level, or a previous shoulder injury. In female players, the ratio was less only in those at a higher skill level. Although speculative, these findings generally suggest that female volleyball players could have a lower risk of developing shoulder-related problems than male volleyball players. Isokinetic shoulder testing may reveal important information about the possible risk

Are squash players protecting their eyes?

Science.gov (United States)

Eime, R M; Finch, C F; Sherman, C A; Garnham, A P

2002-09-01

To determine factors associated with adult squash players' protective eyewear behaviours. A survey of 303 players (aged >or =18 years) was conducted at three squash venues in Melbourne, Australia over a three week period in June 2000 to obtain information about protective eyewear use. Of 303 participants the response rate was 98.1%; 66.1% were males, with a mean age of 40.5 years. The majority (68.4%) had played squash for 10 years or more. Although 18.8% of players reported using protective eyewear, only 8.9% reported wearing approved eyewear. Both age group (peye injuries (50.0%) and knowledge of eye injury risk (33.9%). A commonly reported barrier was restriction of vision (34.2%). These findings demonstrate a low prevalence of voluntary use of appropriate protective eyewear. Future prevention strategies incorporating education campaigns should focus on increasing players' knowledge of risks. The barriers to use and misconceptions about which types of eyewear is most protective need to be addressed as a priority.

Player behavioural modelling for video games

NARCIS (Netherlands)

van Lankveld, G.; Spronck, P.H.M.; Bakkes, S.C.J.

2012-01-01

Player behavioural modelling has grown from a means to improve the playing strength of computer programs that play classic games (e.g., chess), to a means for impacting the player experience and satisfaction in video games, as well as in cross-domain applications such as interactive storytelling. In

Self-determined motivation in rehabilitating professional rugby union players

OpenAIRE

Carson, F.; Polman, Remco C.J.

2017-01-01

Background The aim of the present study was to explore the views of professional rugby union players during the early rehabilitation, late rehabilitation and return to play stages, following anterior cruciate ligament (ACL) injury. Methods A qualitative dominant, mixed methodological approach was utilized with five players who had suffered an ACL injury requiring reconstructive surgery. A longitudinal approach, concurrent with each player?s rehabilitation, consisting of twice monthly intervie...

Physical Characteristics and Performance of Japanese Top-Level American Football Players.

Science.gov (United States)

Yamashita, Daichi; Asakura, Masaki; Ito, Yoshihiko; Yamada, Shinzo; Yamada, Yosuke

2017-09-01

Yamashita, D, Asakura, M, Ito, Y, Yamada, S, and Yamada, Y. Physical characteristics and performance of Japanese top-level American football players. J Strength Cond Res 31(9): 2455-2461, 2017-This study aimed to compare the physical characteristics and performance between top-level nonprofessional football players in Japan and National Football League (NFL) Combine invited players and between top-level and middle-level players in Japan to determine the factors that enhance performance in international and national competitions. A total of 168 American football players (>20 years) in Japan participated in an anthropometric (height and weight) and physical (vertical jump, long jump, 40-yard dash, pro-agility shuttle, 3-cone drill, and bench press repetition test) measurement program based on the NFL Combine program to compete in the selection of candidates for the Senior World Championship. All players were categorized into 1 of the 3 position groups based on playing position: skill players, big skill players, and linemen. Japanese players were additionally categorized into selected and nonselected players for the second tryout. The NFL Combine candidates had significantly better performance than selected Japanese players on all variables except on performance related to quickness among the 3 position groups. Compared with nonselected players, selected Japanese skill players had better performance in the 40-yard dash and bench press test and big skill players had better performance in the vertical jump, broad jump, and 40-yard dash. Selected and nonselected Japanese linemen were not different in any measurements. These results showed the challenges in American football in Japan, which include not only improving physical performance of top-level players, but also increasing the number of football players with good physical performance.

Training Patterns of Wheelchair Basketball Players in Turkey

Science.gov (United States)

Tatar, Yasar

2008-01-01

The aim of this study was to analyze technical drills, warm-up and cool-down exercises used by wheelchair basketball players of the Turkish league in relation to training sessions. 33 male wheelchair basketball players participated in the study (mean age 26.6[plus or minus]5,95 years). All players reported that they used warm-up exercises before…

Prospective study of injury in volleyball players: 6 year results.

Science.gov (United States)

Pastor, M F; Ezechieli, M; Classen, L; Kieffer, O; Miltner, O

2015-01-01

The volleyball game has a high complexity and thus entails a lot of strain to the players. Due to this high and different training and competition strain comprehensive and individual training plans should be developed with competing training objectives in order to prevent injuries. The aim of the study was to analyse prospectively over six seasons the acute and overuse injuries of a German male professional volleyball team. The study included 34 male national league players from season the 2007/08 to 2012/13. All players received a sport medicine examination and a functional diagnosis before each season. Based on the results the players received an individual training plan. The players suffered 186 injuries. The prevalence of acute injuries was 1.94 per player and overuse injuries 0.64 per player. The incidence of acute injuries was 3.3/1000 h volleyball and overuse injuries 1.08/1000 h volleyball. The largest number of injuries was found in the spine. The players had most likely minor injuries. The players had significantly fewer injuries in their second season (1.92) than in their first season (3.25; p= 0.004). It could be concluded that volleyball is a sport with a relative low prevalence of injuries compared to other team sports. The prevalence of injury is 2.58 per player. Due to an injury a player dropped out 16.91 days per season. An individual training program seems to reduce the incidence of injury.

Investigating the Nutritional and Recovery Habits of Tennis Players

Directory of Open Access Journals (Sweden)

James A. Fleming

2018-04-01

Full Text Available In this study, the nutritional and recovery habits of tennis players pre-, during, and post-match-play were investigated. Seventy tennis players completed a bespoke nutrition and recovery habits questionnaire, with questions related to the following areas: match preparation, intra-match nutritional habits, situation dependent variables, and post-match nutrition and recovery. On match day-1, the consumption of balanced meals consisting of carbohydrate (CHO, fat and protein, with some micronutrient considerations were reported by 51% of players. On match-days, CHOs were prioritised prior to match-play with CHO dominant meals consumed by the majority of players. During matches, all players adopted a nutritional strategy, with water (94%, banana(s (86% and sports drinks (50% commonly used. Carbohydrate rich nutritional aids, including sports drinks (80% and energy gels (26% were utilised more readily during long matches (>2 h. The day after match-play, 39% of players reported the consumption of “nothing specific”. Multiple post-match recovery strategies were adopted by 80% of players, with foam rolling (77%, ice baths (40%, protein shake intake (37% and hot baths (26% most used. Findings indicate highly variable eating and recovery habits in tennis players pre-, during and post-match-play, with scope for improved practices.

Investigating the Nutritional and Recovery Habits of Tennis Players.

Science.gov (United States)

Fleming, James A; Naughton, Robert J; Harper, Liam D

2018-04-03

In this study, the nutritional and recovery habits of tennis players pre-, during, and post-match-play were investigated. Seventy tennis players completed a bespoke nutrition and recovery habits questionnaire, with questions related to the following areas: match preparation, intra-match nutritional habits, situation dependent variables, and post-match nutrition and recovery. On match day-1, the consumption of balanced meals consisting of carbohydrate (CHO), fat and protein, with some micronutrient considerations were reported by 51% of players. On match-days, CHOs were prioritised prior to match-play with CHO dominant meals consumed by the majority of players. During matches, all players adopted a nutritional strategy, with water (94%), banana(s) (86%) and sports drinks (50%) commonly used. Carbohydrate rich nutritional aids, including sports drinks (80%) and energy gels (26%) were utilised more readily during long matches (>2 h). The day after match-play, 39% of players reported the consumption of "nothing specific". Multiple post-match recovery strategies were adopted by 80% of players, with foam rolling (77%), ice baths (40%), protein shake intake (37%) and hot baths (26%) most used. Findings indicate highly variable eating and recovery habits in tennis players pre-, during and post-match-play, with scope for improved practices.

Generative Agents for Player Decision Modeling in Games

DEFF Research Database (Denmark)

Holmgård, Christoffer; Liapis, Antonios; Togelius, Julian

2014-01-01

This paper presents a method for modeling player decision making through the use of agents as AI-driven personas. The paper argues that artificial agents, as generative player models, have properties that allow them to be used as psyhometrically valid, abstract simulations of a human player......’s internal decision making processes. Such agents can then be used to interpret human decision making, as personas and playtesting tools in the game design process, as baselines for adapting agents to mimic classes of human players, or as believable, human-like opponents. This argument is explored...... in a crowdsourced decision making experiment, in which the decisions of human players are recorded in a small-scale dungeon themed puzzle game. Human decisions are compared to the decisions of a number of a priori defined “archetypical” agent-personas, and the humans are characterized by their likeness...

Beneficial Long Communication in the Multi-Player Electronic Mail Game

NARCIS (Netherlands)

De Jaegher, K.J.M.

2015-01-01

In the two-player electronic mail game (EMG), as is well-known, the probability of collective action is lower the more confirmations and re-confirmations are made available to players. In the multi-player EMG, however, as we show players may coordinate on equilibria where they require only few of

Decomposition of Multi-player Games

Science.gov (United States)

Zhao, Dengji; Schiffel, Stephan; Thielscher, Michael

Research in General Game Playing aims at building systems that learn to play unknown games without human intervention. We contribute to this endeavour by generalising the established technique of decomposition from AI Planning to multi-player games. To this end, we present a method for the automatic decomposition of previously unknown games into independent subgames, and we show how a general game player can exploit a successful decomposition for game tree search.

Mental Toughness Attributes of Junior Level Medalist Badminton Players

Directory of Open Access Journals (Sweden)

Varghese C. Antony

2016-10-01

Full Text Available The study aims to compare the mental toughness attributes between medalist and non-medalist badminton players and between male and female players. Participants were 15 male and 15 female badminton players aged between 13-19 years (M= 15.71, SD=2.82. Mental toughness questionnaire of Tiwari and Sharma was administered and the data were analyzed by using descriptive statistics and t-test. Medalist players have exhibited higher mean values on self-confidence, attention control, motivation and goal setting attributes. Overall mental toughness of medalists was higher 180.80±17.15 than non-medalists 170.25±20.10. Comparison analysis showed significant difference between medalists and non-medalists on mental toughness attributes: Self-confidence (SCO: p=0.001<0.05, medalists scored (M±SD=31.33±2.10 higher than non-medalists; motivation (MOT: p=0.006<0.05, medalist scored higher (M±SD=33.50±4.07; goal setting (GSE: p=0.044<0.05, medalists scored significantly higher (M±SD=33.55±4.11 than non-medalists. Other attributes did not show any significant difference between medalist and non-medalist players. When compared with gender, no significant difference was observed on mental toughness attributes except attention control (ATNCON: p=0.044<0.05, female players scored (M±SD=38.97±3.08 higher than male players. The findings confirm that mental toughness is a desired attribute which differentiates a medalist and non-medalist player. Connaughton et al., (2007 stated that elite competitive athletes possess better mental toughness. Medalist players displayed better self-confidence than the non-medalists as supported by Kuan and Roy (2007, Loehr (1986. Motivation helps players to achieve their best and enhance mental toughness (Connaughton et al., 2008; Mohammad et al., 2009. Goal setting determines successful performance Weinberg and Weigand (1993, Weinberg (2003. It was concluded that medalist badminton players showed better mental toughness

A Survey on Common Injuries in Recreational Badminton Players

Directory of Open Access Journals (Sweden)

A Muttalib

2009-11-01

Full Text Available The aim of this descriptive study is to determine the incidence of injuries among recreational badminton players. We evaluated 86 recreational badminton players in the city of Malacca; 35 were excluded for fitting the exclusion criteria. The average recreational badminton player was 36.13 years old and had been playing badminton for the past 17.84 years at a frequency of 2.11 times per week. 39.21% of the recreational badminton players complained of recent injuries in relation to playing badminton. Our data showed that the most common injury sustained by recreational badminton players was pain and stiffness at the shoulder joint. None of the injuries sustained by the players in our data were serious enough to warrant any form of surgical intervention. We conclude that badminton is a sport of relatively low risk and that the majority of related injuries were chronic overuse injuries.

Incidence of tinnitus in mp3 player users.

Science.gov (United States)

Figueiredo, Ricardo Rodrigues; Azevedo, Andreia Aparecida de; Oliveira, Patrícia Mello de; Amorim, Sandro Pereira Vasconcellos; Rios, Artur Guedes; Baptista, Vanderlei

2011-06-01

Exposure to loud noise is one of the main causes of tinnitus. To analyze the incidence of tinnitus in mp3 player users and non-users. One hundred subjects aged from 15 to 30 years were enrolled, 54 of them were regular mp3 player users and 46 were not. Patients with continuous tinnitus for at least 6 months completed the Tinnitus Handicap Inventory (THI) and were tested with high frequency audiometry and transient-evoked otoacoustic emissions (TAOE). A cross-sectional cohort study. The incidence of tinnitus in non-users was about 8 %; in mp3 player users it was about 28 %, a statistically significant difference. Hearing thresholds at 8 kHz were significantly higher in tinnitus patients that used mp3 portable players.TAOE were reduced at 2 kHz in the users group. No statistically significant difference was found in the THI scores between the two groups. Tinnitus was more frequent in teenagers and young adults who regularly listen to mp3 music in players. Moreover, the incidence of tinnitus among mp3 player users was associated with higher hearing thresholds at 8 kHz and lower TOAE at 2 kHz.

Female Chess Players Outperform Expectations When Playing Men.

Science.gov (United States)

Stafford, Tom

2018-03-01

Stereotype threat has been offered as a potential explanation of differential performance between men and women in some cognitive domains. Questions remain about the reliability and generality of the phenomenon. Previous studies have found that stereotype threat is activated in female chess players when they are matched against male players. I used data from over 5.5 million games of international tournament chess and found no evidence of a stereotype-threat effect. In fact, female players outperform expectations when playing men. Further analysis showed no influence of degree of challenge, player age, nor prevalence of female role models in national chess leagues on differences in performance when women play men versus when they play women. Though this analysis contradicts one specific mechanism of influence of gender stereotypes, the persistent differences between male and female players suggest that systematic factors do exist and remain to be uncovered.

Perceptions of football players regarding injury risk factors and prevention strategies.

Directory of Open Access Journals (Sweden)

Astrid Zech

Full Text Available Current approaches regarding injury prevention focus on the transfer of evidence into daily practice. One promising approach is to influence attitudes and beliefs of players. The objective of this study was to record player's perceptions on injury prevention. A survey was performed among players of one German high-level football (soccer club. 139 professional and youth players between age 13 and 35 years completed a standardized questionnaire (response rate = 98%. It included categories with (1 history of lower extremity injuries, (2 perceptions regarding risk factors and (3 regularly used prevention strategies. The majority of players (84.2% had a previous injury. 47.5% of respondents believe that contact with other players is a risk factor, followed by fatigue (38.1% and environmental factors (25.9%. The relevance of previous injuries as a risk factor is differently perceived between injured (25% and uninjured players (0.0%. Nearly all players (91.5% perform stretching to prevent injuries, followed by neuromuscular warm up exercises (54.0%. Taping is used by 40.2% of previously injured players and 13.6% of players without a history of injuries. In conclusion, the perception of risk factors and performed preventive strategies are inconsistent with scientific evidence. Future transfer strategies should incorporate the players beliefs and attitudes.

Performance following a first professional concussion among National Basketball Association players.

Science.gov (United States)

Yengo-Kahn, Aaron M; Zuckerman, Scott L; Stotts, Jeff; Zalneraitis, Brian H; Gardner, Ryan M; Kerr, Zachary Y; Solomon, Gary S

2016-09-01

Basketball is a physical game played on a hardwood floor among high-jumping athletes at risk for injury. It is currently unknown how sport-related concussion (SRC) affects player performance after injury among professional basketball players. The objective of this study was to explore the impact of SRC on basketball performance among National Basketball Association (NBA) players. A retrospective, archival cohort study was performed that compared NBA player performance following concussion to pre-concussive performance. A comprehensive NBA injury database, compiled from publically available sources, was queried for NBA players who suffered concussion from 2005-06 to 2014-15 (10 seasons). Intra-and inter-player analyses were performed against a matched control group of players who missed playing time for personal reasons. Following application of inclusion/exclusion criteria and a matching process, 51 concussed players and 51 control players were included in analysis. There were no statistically significant decrements in baseline to post-concussion performance metrics in intra-player or player vs. controls after 5 return games. Our findings suggest that at the NBA level, an athlete's performance in the initial 5 games following injury does not suffer from the after-effects of concussive injury. These results may be useful in counseling professional athletes following a concussion.

Genome-wide profiling of the PIWI-interacting RNA-mRNA regulatory networks in epithelial ovarian cancers.

Science.gov (United States)

Singh, Garima; Roy, Jyoti; Rout, Pratiti; Mallick, Bibekanand

2018-01-01

PIWI-interacting (piRNAs), ~23-36 nucleotide-long small non-coding RNAs (sncRNAs), earlier believed to be germline-specific, have now been identified in somatic cells, including cancer cells. These sncRNAs impact critical biological processes by fine-tuning gene expression at post-transcriptional and epigenetic levels. The expression of piRNAs in ovarian cancer, the most lethal gynecologic cancer is largely uncharted. In this study, we investigated the expression of PIWILs by qRT-PCR and western blotting and then identified piRNA transcriptomes in tissues of normal ovary and two most prevalent epithelial ovarian cancer subtypes, serous and endometrioid by small RNA sequencing. We detected 219, 256 and 234 piRNAs in normal ovary, endometrioid and serous ovarian cancer samples respectively. We observed piRNAs are encoded from various genomic regions, among which introns harbor the majority of them. Surprisingly, piRNAs originated from different genomic contexts showed the varied level of conservations across vertebrates. The functional analysis of predicted targets of differentially expressed piRNAs revealed these could modulate key processes and pathways involved in ovarian oncogenesis. Our study provides the first comprehensive piRNA landscape in these samples and a useful resource for further functional studies to decipher new mechanistic views of piRNA-mediated gene regulatory networks affecting ovarian oncogenesis. The RNA-seq data is submitted to GEO database (GSE83794).

Big Data for Business Ecosystem Players

Directory of Open Access Journals (Sweden)

Perko Igor

2016-06-01

Full Text Available In the provided research, some of the Big Data most prospective usage domains connect with distinguished player groups found in the business ecosystem. Literature analysis is used to identify the state of the art of Big Data related research in the major domains of its use-namely, individual marketing, health treatment, work opportunities, financial services, and security enforcement. System theory was used to identify business ecosystem major player types disrupted by Big Data: individuals, small and mid-sized enterprises, large organizations, information providers, and regulators. Relationships between the domains and players were explained through new Big Data opportunities and threats and by players’ responsive strategies. System dynamics was used to visualize relationships in the provided model.

EVALUATING AUSTRALIAN FOOTBALL LEAGUE PLAYER CONTRIBUTIONS USING INTERACTIVE NETWORK SIMULATION

Directory of Open Access Journals (Sweden)

Jonathan Sargent

2013-03-01

Full Text Available This paper focuses on the contribution of Australian Football League (AFL players to their team's on-field network by simulating player interactions within a chosen team list and estimating the net effect on final score margin. A Visual Basic computer program was written, firstly, to isolate the effective interactions between players from a particular team in all 2011 season matches and, secondly, to generate a symmetric interaction matrix for each match. Negative binomial distributions were fitted to each player pairing in the Geelong Football Club for the 2011 season, enabling an interactive match simulation model given the 22 chosen players. Dynamic player ratings were calculated from the simulated network using eigenvector centrality, a method that recognises and rewards interactions with more prominent players in the team network. The centrality ratings were recorded after every network simulation and then applied in final score margin predictions so that each player's match contribution-and, hence, an optimal team-could be estimated. The paper ultimately demonstrates that the presence of highly rated players, such as Geelong's Jimmy Bartel, provides the most utility within a simulated team network. It is anticipated that these findings will facilitate optimal AFL team selection and player substitutions, which are key areas of interest to coaches. Network simulations are also attractive for use within betting markets, specifically to provide information on the likelihood of a chosen AFL team list "covering the line".

Coping strategies of soccer players | Plaatjie | South African Journal ...

African Journals Online (AJOL)

This study focused on coping strategies used by soccer (football) players by exploring the role of the environment, ethnicity and culture in players' response to stressful situations. An interpretive-qualitative research methodology was applied with a sample of 33 professional soccer players. The subjects were representative ...

Time-motion analysis and physiological responses of small-sided team handball games in youth male players: Influence of player number

Directory of Open Access Journals (Sweden)

Jan Bělka

2016-12-01

Full Text Available Background: Effective training depends on knowledge of a sport's requirements. Small-sided games (SSG are a spontaneous form of specific training, where exercise intensity can be manipulated mainly by modifying external factors. In SSG the players develop technical and tactical skills in the similar situations, such as during a match and can also develop their physical skills. Objective: The purpose of this study was to examine the distance covered and physiological response of altering the number of youth male players during small-sided team handball games with modified rules. Methods: The subjects consisted of 12 male youth team handball players (age 16.6 ± 0.5 years playing the first league for youth male players in the Czech Republic. The study was conducted during six weeks (one training session per week. Only three SSG were played in each training session. The SSG were played, first with five players on each side (5 vs. 5, then four (4 vs. 4, then three (3 vs. 3. Each game was four minutes long, followed by three minutes of passive rest. Results: The players covered the greatest distance (520.6 ± 61.4 m in the SSG 3 vs. 3. There was a difference in the distance covered between players in the 3 vs. 3 SSG and the other SSG (4 vs. 4 and 5 vs. 5 (p = .041 and p = .043, respectively. In individual speed zones a difference occurred only in the first and third speed zone and always among the 3 vs. 3 and 5 vs. 5 SSG (p = .034 and p = .044, respectively. The highest average intensity (87.9 ± 4.8% HRmax was in 3 vs. 3 SSG. Loading of the players in 5 vs. 5 was lower compared to 4 vs. 4 (p = .035 and 3 vs. 3 (p < .001. There was a difference in zone load intensity (> 90% HRmax between 3 vs. 3 and 5 vs. 5 SSG (p = .041. Conclusions: These results indicate that changing the number of players during SSG with modified rules in youth team handball may be used to manipulate the physiological response

Efficiently detecting outlying behavior in video-game players

Directory of Open Access Journals (Sweden)

Young Bin Kim

2015-12-01

Full Text Available In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players’ characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.

Upper extremity sensorimotor control among collegiate football players.

Science.gov (United States)

Laudner, Kevin G

2012-03-01

Injuries stemming from shoulder instability are very common among athletes participating in contact sports, such as football. Previous research has shown that increased laxity negatively affects the function of the sensorimotor system potentially leading to a pathological cycle of shoulder dysfunction. Currently, there are no data detailing such effects among football players. Therefore, the purpose of this study was to examine the differences in upper extremity sensorimotor control among football players compared with that of a control group. Forty-five collegiate football players and 70 male control subjects with no previous experience in contact sports participated. All the subjects had no recent history of upper extremity injury. Each subject performed three 30-second upper extremity balance trials on each arm. The balance trials were conducted in a single-arm push-up position with the test arm in the center of a force platform and the subjects' feet on a labile device. The trials were averaged, and the differences in radial area deviation between groups were analyzed using separate 1-way analyses of variance (p football players showed significantly more radial area deviation of the dominant (0.41 ± 1.23 cm2, p = 0.02) and nondominant arms (0.47 ± 1.63 cm2, p = 0.03) when compared with the control group. These results suggest that football players may have decreased sensorimotor control of the upper extremity compared with individuals with no contact sport experience. The decreased upper extremity sensorimotor control among the football players may be because of the frequent impacts accumulated during football participation. Football players may benefit from exercises that target the sensorimotor system. These findings may also be beneficial in the evaluation and treatment of various upper extremity injuries among football players.

Finite stage asymmetric repeated games: Both players' viewpoints

KAUST Repository

Li, Lichun; Feron, Eric; Shamma, Jeff S.

2017-01-01

the opponents' corresponding best responses depends only on the informed player's history action sequences. Moreover, efficient LP formulations to compute both player's security strategies are provided.

I Fought the Law: Transgressive Play and The Implied Player

DEFF Research Database (Denmark)

Aarseth, Espen J.

2007-01-01

This paper is an attempt to understand Game Studies through the contested notion of the “player” both inside and outside “the game object” – that is the object that game users perceive and respond to when they play. Building on Hans-Georg Gadamer’s notion of games as a subject that “masters...... the players”, the paper will go beyond the traditional split between the social sciences’ real players and the aesthetics/humanities critical author-as-player, and present a theory of the player and player studies that incorporates the complex tensions between the real, historical player and the game’s human...... components. Since games are both aesthetic and social phenomena, a theory of the player must combine both social and aesthetic perspectives to be successful. The tension between the humanities and the social sciences over who controls the idea of the player can be found mirrored also in the struggle between...

How should "hot" players in basketball be defended? The use of fast-and-frugal heuristics by basketball coaches and players in response to streakiness.

Science.gov (United States)

Csapo, Peter; Avugos, Simcha; Raab, Markus; Bar-Eli, Michael

2015-01-01

Previous research has shown that changes in shot difficulty may have rendered the hot-hand effect in basketball unobservable and are potentially a result of defensive adjustments. However, it has not been directly analysed whether strategic changes indeed take place in response to streakiness and whether they are effective with respect to winning games. The current work consists of an experimental study with 18 professional coaches and 20 players based on video sequences from National Basketball Association games, where the shown player displayed a streaky performance in half of the sequences. While coaches were asked to devise a defensive strategy after each viewed sequence, players had to assume the role of the shown player and decide whether to shoot or pass the ball. We find that coaches tended to increase the defensive pressure significantly more often on presumably hot players and thus make use of the hot-hand heuristic. Meanwhile, players chose to shoot more frequently in low-pressure and streaky situations but selected "pass" regardless of the previous performance when they faced increased defensive pressure. Assuming that a streaky player's performance is indeed elevated during hot phases, hot-hand behaviour can be considered adaptive in certain situations as it led hot players to pass instead of shoot.

Soccer player recognition by pixel classification in a hybrid color space

Science.gov (United States)

Vandenbroucke, Nicolas; Macaire, Ludovic; Postaire, Jack-Gerard

1997-08-01

Soccer is a very popular sport all over the world, Coaches and sport commentators need accurate information about soccer games, especially about the players behavior. These information can be gathered by inspectors who watch the soccer match and report manually the actions of the players involved in the principal phases of the game. Generally, these inspectors focus their attention on the few players standing near the ball and don't report about the motion of all the other players. So it seems desirable to design a system which automatically tracks all the players in real- time. That's why we propose to automatically track each player through the successive color images of the sequences acquired by a fixed color camera. Each player which is present in the image, is modelized by an active contour model or snake. When, during the soccer match, a player is hidden by another, the snakes which track these two players merge. So, it becomes impossible to track the players, except if the snakes are interactively re-initialized. Fortunately, in most cases, the two players don't belong to the same team. That is why we present an algorithm which recognizes the teams of the players by pixels representing the soccer ground which must be withdrawn before considering the players themselves. To eliminate these pixels, the color characteristics of the ground are determined interactively. In a second step, dealing with windows containing only one player of one team, the color features which yield the best discrimination between the two teams are selected. Thanks to these color features, the pixels associated to the players of the two teams form two separated clusters into a color space. In fact, there are many color representation systems and it's interesting to evaluate the features which provide the best separation between the two classes of pixels according to the players soccer suit. Finally, the classification process for image segmentation is based on the three most

[Muscular trunk stability in professional and amateur volleyball players].

Science.gov (United States)

Miltner, O; Siebert, C; Tschaepe, R; Maus, U; Kieffer, O

2010-03-01

The aim of this study was to analyse the efficiency of muscular activity in the trunk stabilisation of professional volleyball players compared to a group of amateur hobby players. The results were compared amongst the groups as well as with a reference group consisting of asymptomatic individuals. The question to be answered was whether or not professional volleyball players possess a characteristic strength profile in their trunk musculature and if differences exist with regard to the individuals' competitive playing level. In this comparative study 12 professional volleyball players (German Bundesliga) and 18 non-professional volleyball players were analysed with regard to their isometric strength profile in all three planes. The reference group was provided by the Proxomed company, which had previously analysed healthy untrained individuals (n = 1045) of various age groups. A sports-specific profile for the musculature of volleyball players revealed a significant reduction in the flexion and rotation strength as well as a well-developed lateral flexion strength (highly significant when compared to the reference group). With reference to the level played, better strength values in flexion and lateral flexion were found among the professional athletes. Professional volleyball players present with a characteristic trunk musculature strength profile. A detailed analysis of the muscle strength of the spine as part of a sports medicine work-up could prove helpful in preventing injuries and overuse problems in professional and hobby volleyball players.

Risk Factors for Injuries in Professional Football Players.

Science.gov (United States)

Haxhiu, Bekim; Murtezani, Ardiana; Zahiti, Bedri; Shalaj, Ismet; Sllamniku, Sabit

2015-01-01

The aim of this study was to identify risk factors related to the occurrence of injuries in football players. The study included 216 football players from 12 teams in the elite football league. Football-related injury data were collected prospectively during the 2012/2013 competitive season. At baseline the following information was collected for the players: anthropometric measurements (weight, height, BMI, subcutaneous skinfolds), playing experience, injury history, physical fitness performance test (agility run), peak oxygen uptake. The incidence, type and severity of injuries and training and game exposure times were prospectively documented for each player. Most of the players (n = 155, 71.7%) sustained the injures during the study period. The overall injury incidence during the regular season was 6.3 injuries per 1000 athlete-exposures (95% confidence interval, 4.31-9.67). Multivariate logistic regression analysis showed that playing experience (odds ratio [OR] = 0.44; 95% CI = 0.32-0.61, p football for more than 1 month, with knee injuries (25.42%) being the most severe type. The risk factors that increase injury rates in football players were previous injury, higher age and years of playing. Future research should include adequate rehabilitation program to reduce the risk of injuries.

Menstrual cycle disorders in female volleyball players.

Science.gov (United States)

Wodarska, M; Witkoś, J; Drosdzol-Cop, A; Dąbrowska, J; Dąbrowska-Galas, M; Hartman, M; Plinta, R; Skrzypulec-Plinta, V

2013-07-01

The aim of this study was to examine the relation between increased physical activity and menstrual disorders in adolescent female volleyball players. The study was conducted on 210 Polish female volleyball players, aged 13-17 years, the authorship questionnaire was used. The results of the study showed that irregular menstruation occurred in 19% of girls, spotting between menstrual periods in 27% and heavy menstruation was reported in 33% of girls. Out of all volleyball female players participating in the study, 94 girls (45%) declared absence of menstrual periods after regular cycles. Statistical analysis showed that the more training hours per week, the bigger probability of the occurrence of irregular menstruation. It was concluded that the number of hours of volleyball training per week affects regularity of menstrual cycles in female volleyball players. The absence of menstruation might be caused by the duration of training per week or years of training.

Bone Mineral Density of Adolescent Female Tennis Players and Nontennis Players

Directory of Open Access Journals (Sweden)

Kevser Ermin

2012-01-01

Full Text Available The purpose of this study was to determine differences in bone mineral density (BMD among adolescent female tennis players (TPs and nontennis players (NTPs and to assess body composition as a predictor variable of BMD. Nineteen female TPs and 19 female NTPs, ages 14 to 18 years, participated in this study. Lumbar spine, total hip, femoral neck, forearms BMD, and body composition were assessed using dual-energy X-ray absorptiometry (DXA. Lumbar spine and total hip BMD measurements for TP were greater than NTP. However, these differences were not statistically significant (=0.37 and 0.12, resp.. TP had significantly greater femoral neck BMD than NTPs (=0.02. This difference might play an important role in preventing osteoporosis and decreasing the risk of fractures at the hip later in life.

Effect of Concussion on Performance of National Football League Players.

Science.gov (United States)

Reams, Nicole; Hayward, Rodney A; Kutcher, Jeffrey S; Burke, James F

2017-09-01

Lingering neurologic injury after concussion may expose athletes to increased risk if return to play is premature. The authors explored whether on-field performance after concussion is a marker of lingering neurologic injury. Retrospective cohort study on 1882 skill-position players who played in the National Football League (NFL) during 2007-2010. Players with concussion based on the weekly injury report were compared with players with other head and neck injuries (controls) on measures of on-field performance using Football Outsiders' calculation of defense-adjusted yards above replacement (DYAR), a measure of a player's contribution controlling for game context. Changes in performance, relative to a player's baseline level of performance, were estimated before and after injury using fixed-effects models. The study included 140 concussed players and 57 controls. Players with concussion performed no better or worse than their baseline on return to play. However, a decline in DYAR relative to their prior performance was noted 2 wk and 1 wk before appearing on the injury report. Concussed players performed slightly better than controls in situations where they returned to play the same week as appearing on the injury report. On return, concussed NFL players performed at their baseline level of performance, suggesting that players have recovered from concussion. Decline in performance noted 2 wk and 1 wk before appearing on the injury report may suggest that concussion diagnosis was delayed or that concussion can be a multihit phenomenon. Athletic performance may be a novel tool for assessing concussion injury and recovery.

Tracking of ball and players in beach volleyball videos.

Directory of Open Access Journals (Sweden)

Gabriel Gomez

Full Text Available This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points.

Linking performance decline to choking: players' perceptions in basketball.

Science.gov (United States)

Fryer, Ashley Marie; Tenenbaum, Gershon; Chow, Graig M

2018-02-01

This study was aimed at examining how basketball players view unexpected performance errors in basketball, and under what conditions they perceive them as choking. Fifty-three basketball players were randomly assigned into 2 groups (game half) to evaluate the linkage between performance decline and choking as a function of game-time, score gap and game half. Within each group, players viewed 8 scenario clips, which featured a different player conducting an error, and subsequently rated the extent of performance decline, the instance of choking and the salience of various performance attributions regarding the error. The analysis revealed that choking was most salient in the 2nd half of the game, but an error was perceived as choking more saliently in the beginning of the 2nd half. This trend was also shown for players' perception of performance decline. Players' ratings of the attributions assigned to errors, however, revealed that during the end of the 2nd half, time pressure and lack of concentration were the causes of errors. Overall, the results provide evidence towards a conceptual framework linking performance decline to the perception of choking, and that errors conducted by players are perceived as choking when there is not a salient reason to suggest its occurrence.

Differences in energy capacities between tennis players and runners.

Science.gov (United States)

Novak, Dario; Vucetić, Vlatko; Zugaj, Sanja

2013-05-01

The primary purpose of this study was to determine differences between elite athletes and tennis players in order to provide a clearer picture regarding the energy demands in modern tennis. Forty-eight (48) athletes and 24 tennis players from Croatian national leagues were compared in morphological and physiological parameters of an all-out incremental treadmill test with gas exchange measurements. Tennis players' HRmax (192.96+/-7.75 bpm) shows values that are most different to 400-meters sprinters (200.13+/-6.95 bpm). Maximum running speed of tennis players on the treadmill (vmax) is no different with the speed achieved by sprinters, while there are significant differences among other athletes. Values in running speed at anaerobic threshold (vAnT) show no statistically significant difference with the values for athlete sprinters and 400-m sprinters. Values of RvO2max for tennis players indicate significant similarities with athlete sprinters and 400-m sprinters while the values of RvO2AnT are nearly identical with the values for sprinters and show no statistically significant differences (psprint endurance in tennis players. Knowing these characteristics is the basis for planning and implementing training systems that will enable the increase and optimal usage of energy capacities of tennis players in possibly improving sports results.

Tracking of Ball and Players in Beach Volleyball Videos

Science.gov (United States)

Gomez, Gabriel; Herrera López, Patricia; Link, Daniel; Eskofier, Bjoern

2014-01-01

This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points. PMID:25426936

Arthroscopic rotator cuff repair in elite rugby players

OpenAIRE

Tambe, Amol; Badge, Ravi; Funk, Lennard

2009-01-01

Background: Rugby is an increasingly popular collision sport. A wide spectrum of injuries can be sustained during training and match play. Rotator cuff injury is uncommon in contact sports and there is little published literature on the treatment of rotator cuff tears in rugby players. Aims: We therefore reviewed the results and functional outcomes of arthroscopic rotator cuff repair in elite rugby players. Materials and Methods: Eleven professional rugby players underwent arthroscopic ...

An Optimized Player Taxonomy Model for Mobile MMORPGs with Millions of Users

Directory of Open Access Journals (Sweden)

Fang You

2011-01-01

Full Text Available Massively multiplayer online role-playing games (MMORPGs have great potential as sites for research within the social and human-computer interaction. In the MMORPGs, a stability player taxonomy model is very important for game design. It helps to balance different types of players and improve business strategy of the game. The players in mobile MMORPGs are also connected with social networks; many studies only use the player's own attributes statistics or questionnaire survey method to predict player taxonomy, so lots of social network relations' information will be lost. In this paper, by analyzing the impacts of player's social network, commercial operating data from mobile MMORPGs is used to establish our player taxonomy model (SN model. From the model results, social network-related information in mobile MMORPGs will be considered as important factors to pose this optimized player taxonomy model. As experimental results showed, compared with another player taxonomy model (RA model, our proposed player taxonomy model can achieve good results: classification is more stable.

Exploring Online Game Players' Flow Experiences and Positive Affect

Science.gov (United States)

Chiang, Yu-Tzu; Lin, Sunny S. J.; Cheng, Chao-Yang; Liu, Eric Zhi-Feng

2011-01-01

The authors conducted two studies to explore online game players' flow experiences and positive affect. Our findings indicated that online game are capable of evoking flow experiences and positive affect, and games of violent or nonviolent type may not arouse players' aggression. The players could be placed into four flow conditions: flow,…

Foot morphology of Turkish football players according to foot ...

African Journals Online (AJOL)

Football is the most popular sport in the world. Foot morphology and foot preference are important factors in football player's performance. The aim of this cross-sectional study was to evaluate the foot morphology of elite football players with different foot preferences. 407 male football players participated in this study. 328 of ...

Soccer and Relative Age Effect: A Walk among Elite Players and Young Players

Directory of Open Access Journals (Sweden)

Manuel Jacob Sierra-Díaz

2017-01-01

Full Text Available Grouping people according to chronological age is popular in fields such as education and sport. Athletes who are born in the first months of the year usually have cognitive and physical development differences in contrast to those born in the last months of the same year. That is why competitive teams tend to select older players more often than youngsters. Age differences between athletes born in the same year as well as an over-representation of older players are known as the Relative Age Effect. This effect is extensively described in young and elite team sports such as basketball, volleyball or, ice-hockey, as well as in soccer. The purpose of this study is to examine the state-of-the-art of the Relative Age Effect in youth and elite soccer players. This review summarizes recent research articles on the Relative Age Effect related to competitive soccer from 2010 to 2016. The systematic literature search was conducted in four databases: SPORTDiscus, Medline, EBSCO host and Google Scholar. Although causes and final solutions have not been clearly achieved yet, it is necessary to continue investigating this phenomenon in order to provide a starting point for future research.

Training habits and injuries of masters' level football players: a preliminary report.

Science.gov (United States)

Newsham-West, R; Button, C; Milburn, P D; Mündermann, A; Sole, G; Schneiders, A G; Sullivan, S J

2009-05-01

To profile training habits and injuries in football players participating in a national Masters tournament. A cross-sectional retrospective study design was used to survey male football players attending the 2008 New Zealand Masters Games. Information regarding player demographics, football injuries, football related training, and risk factors for injury were collected. 199 Players were recruited, with a median age of 44 yrs (range 35-73) and a median football playing history of 15 yrs (range 0-66). Irrespective of age, 112 (84%) players included a warm-up and 104 (78%) included a stretching regime in their regular training programme. In the 12 months prior to the tournament, 128 football related injuries were reported by 93 players (64 injuries/100 players or 46 injured players/100 players). The most frequently injured region was the lower limb; specifically the lower leg (n=23), ankle (n=18), hamstring (n=17), knee (n=15), and Achilles tendon (n=15). This study provides a preliminary insight into the training habits and injury profiles of Masters football players. Despite all players including some form of injury prevention strategy in their training, a significant number of players experienced an injury in the 12 months prior to the tournament.

Relations of competitive state anxiety and efficacy of young volleyball players.

Science.gov (United States)

Milavić, Boris; Jurko, Damir; Grgantov, Zoran

2013-05-01

With the aim of validating the Competitive State Anxiety Inventory on a population of young Croatian volleyball players, 286 examinees, 106 male and 180 female volleyball players (average age of 16.09+/-1.83), filled out the CSAI-2, constructed by Martens, Vealey, Burton, Bump and Smith (1990)1. Given the fact that all scales of the Competitive State Anxiety Inventory have good homogeneity, reliability and sensitivity, it can be concluded that they represent high-quality measuring instruments for measuring psychological characteristics of young volleyball players. Young male and female volleyball players generally have a moderate level of self-confidence, and their cognitive anxiety is more prominent that somatic anxiety. In order to determine the age and gender differences in somatic and cognitive anxiety and self-confidence, parametric analysis of differences was performed and coefficients of the independent samples t-test were calculated. By analysis of differences according to age, it has been established that female junior players, in relation to female youth players, express a significantly lower level of somatic and cognitive anxiety and a significantly higher level of self-confidence. As opposed to female players, male youth and junior players do not differ in any of the analysed variables. By analysis of differences according to gender, it has been established that male youth players have a significantly higher level of self-confidence in comparison to female youth players. No significant differences were found in the level of competitive anxiety and self-confidence by analysis of variance between different player roles. No significant differences were found by discriminant analysis in somatic and cognitive anxiety, and self-confidence of female volleyball players of different situational efficacy. The group of least efficient male volleyball players is characterized by a very low level of self-confidence, while the most efficient group of volleyball

Computing Decoupled Residuals for Compact Disc Players

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Stoustrup, Jakob; Andersen, Palle

2006-01-01

a pair of residuals generated by Compact Disc Player. However, these residuals depend on the performance of position servos in the Compact Disc Player. In other publications of the same authors a pair of decoupled residuals is derived. However, the computation of these alternative residuals has been...

Physiological characteristics of elite soccer players.

Science.gov (United States)

Tumilty, D

1993-08-01

Soccer is one of the most popular sports in the world. There is still much uncertainty and debate surrounding its physiological requirements because emphasis is on skills to the neglect of fitness, conservative training methods and the difficulty of studying the sport scientifically. The frequently found values for total distance covered in a game of about 10 km and an above-average, though not outstanding, maximum oxygen uptake of 60 ml/kg/min suggest a moderate overall aerobic demand. A comparison of top teams and players with less able participants indicates that the components of anaerobic fitness-speed, power, strength and the capacity of the lactic acid system may differentiate better between the 2 groups. Generally, there is a reduction in the level of activity in the second half of games compared with the first. There is some evidence that increased aerobic fitness may help counteract this. Progressively lower muscle glycogen stores are one likely cause of reduction in activity, and nutrition also appears to be a key factor in minimising performance deterioration, both in terms of overall diet and, more particularly, the ingestion of carbohydrates immediately before, during and after a game. There are evolutionary trends in the sport such as greater frequency of games, changes in the roles of players, and new strategies and tactics which are placing increasing demands on the all-round fitness of players. Many studies indicate scope for improvement in player fitness. The challenge for coaches and players is to meet these fitness requirements without sacrificing the skill work which makes the sport unique.

Clustering Professional Basketball Players by Performance

OpenAIRE

Patel, Riki

2017-01-01

Basketball players are traditionally grouped into five distinct positions, but these designationsare quickly becoming outdated. We attempt to reclassify players into new groupsbased on personal performance in the 2016-2017 NBA regular season. Two dimensionalityreduction techniques, t-Distributed Stochastic Neighbor Embedding (t-SNE) and principalcomponent analysis (PCA), were employed to reduce 18 classic metrics down to two dimensionsfor visualization. k-means clustering discovered four grou...

Exploring Stereotypical Perceptions of Female Players in Digital Gaming Contexts.

Science.gov (United States)

Kaye, Linda K; Gresty, Claire E; Stubbs-Ennis, Natasha

2017-12-01

Gender stereotypes are still reported to exist in digital gaming contexts, despite the fact that participation of females is relatively equal to that of males. The current research explored a number of factors and their impact upon stereotypical perceptions and attitudes toward female players. This included avatar gender, gender identity by gaming context, as well as more general gender-role beliefs. We undertook two studies, each utilizing an online questionnaire targeted toward online players. Study 1 recruited online gamers (N = 489) and compared competence perceptions of players, which varied by player gender (male, female) and avatar gender (male, female), whereby four conditions were established. Overall, player competence was perceived to be highest when male avatars were used, specifically when female players were depicted in this way. Study 2 explored the relationships between male social identity and gender-role beliefs, with sexist attitudes in gaming, and whether this varied by gaming context (massively multiplayer online [MMO] vs. first-person shooter [FPS]). Male online gamers (N = 193) were recruited, of which 112 were MMO players, and 81 were FPS players. It was found that identifying as male social identity was not related to sexist attitudes in either gaming context. However, more general gender-role beliefs were related to sexist attitudes. The findings indicate that although certain stereotypes exist (e.g., competence perceptions), these are not necessarily harvested by players' identities within communities, but may derive through more operational functions such as avatar gender.

Physical and physiological attributes of female volleyball players--a review.

Science.gov (United States)

Lidor, Ronnie; Ziv, Gal

2010-07-01

The main objective of this article was to review a series of studies (n = 31) on physical attributes, physiological attributes, and on-court performances of female volleyball players. Empirical and practical knowledge emerging from studies on training-related issues in volleyball, such as body mass, fat-free mass, aerobic profile, strength, and agility and speed, should be integrated and applied when planning annual training programs for volleyball players. Based on our review, it was found that (a) players of a higher skill level are taller, somewhat heavier, and have higher vertical jump values than players of a lower level; (b) the aerobic profile of female volleyball players is similar to that of female basketball players; (c) ballistic resistance training can increase vertical jump values in female volleyball players; and (d) preseason conditioning should be conducted to prevent fatigue and reduced performance at the beginning of the season. Among the research concerns discussed in the article are that there is a lack data for on-court performance and time-motion analysis in female volleyball players and that more experimental/manipulative studies are needed to examine the effectiveness of different training programs on physiological attributes of female volleyball players. Two practical implications are suggested for volleyball and strength and conditioning coaches: (a) functional and nonfunctional overreaching should be carefully monitored when planning strength and conditioning programs, and (b) volleyball programs should include ballistic-type training.

A Profile of Fitness Parameters and Performance of Volleyball Players

Directory of Open Access Journals (Sweden)

Govind B. Taware

2013-07-01

Full Text Available Background: Ball games require comprehen-sive ability including physical, technical, men-tal and tactical abilities. Among them, physicalabilities of players exert marked effects on theskill of the players themselves and the tacticsof the team. Therefore players must have thephysical abilities to meet the demand of thesport. Volleyball is one of the most popularlyplayed games in the world. Unfortunately, thelevel of performance of the Indian volleyballplayers lags far behind the international stan-dards. Aim of the Study: The present study wasaimed to assess flexibility, muscular endurance,power and cardio-respiratory endurance of vol-leyball players and to compare the results withage matched controls. Also, to compare thefindings of the volleyball players with that ofthe international norms from the available lit-erature and to make some suggestions for theimprovement in their performance level. Ma-terial and Methods: The study was carried outin 40 male volleyball players aged between 17to 26 years and 40 ages matched male controls.Physical fitness parameters namely flexibility,muscular endurance, power and cardio-respi-ratory endurance were measured, data was ana-lyzed using unpaired ‘t’-test. Results: It was ob-served that all physical fitness parameters weresignificantly more in players as compared totheir aged-matched controls but when values ofthe subjects were compared to internationalstandards; our subjects were behind the recom-mended norms for the elite volleyball players.Conclusion: The volleyball players have moreadvantage of flexibility muscular endurance,power and cardio-respiratory endurance.

Speed and countermovement-jump characteristics of elite female soccer players, 1995-2010.

Science.gov (United States)

Haugen, Thomas A; Tønnessen, Espen; Seiler, Stephen

2012-12-01

The purpose of this investigation was to compare sprint and countermovement-jump (CMJ) performance among female competitive soccer players as a function of performance level, field position, and age. In addition, the authors wanted to quantify the evolution of these physical characteristics among elite players over a 15-y period. 194 female elite players (22± 4.1 y, 63 ± 5.6 kg), including an Olympic winning squad, tested 40-m sprint with electronic timing and CMJ on a force platform at the Norwegian Olympic training center from 1995 to 2010. Moderate to large velocity differences across performance levels and positions were observed. National-team players were 2% faster than 1st-division players (P = .027, d = 0.5) and 5% faster than 2nd-division players (P players jumped 8-9% higher than 1st-division players (P = .001, d = 0.6) and junior elite players (P = .023, d = 0.5). Forwards were 3-4% faster than midfielders (P Players from 2006-2010 were 2% faster (P players from 1995-1999 over 20 m, whereas no differences in 20- to 40-m velocity or CMJ performance were observed. This study provides effect-magnitude estimates for the influence of performance level, age, and player position on sprint and CMJ performance in female soccer players. While 20- to 40-m velocity and CMJ performance have remained stable over the time, there has been a moderate but positive development in 0- to 20-m velocity among elite performers.

Sports hernia in National Hockey League players: does surgery affect performance?

Science.gov (United States)

Jakoi, Andre; O'Neill, Craig; Damsgaard, Christopher; Fehring, Keith; Tom, James

2013-01-01

Athletic pubalgia is a complex injury that results in loss of play in competitive athletes, especially hockey players. The number of reported sports hernias has been increasing, and the importance of their management is vital. There are no studies reporting whether athletes can return to play at preinjury levels. The focus of this study was to evaluate the productivity of professional hockey players before an established athletic pubalgia diagnosis contrasted with the productivity after sports hernia repair. Cohort study; Level of evidence, 3. Professional National Hockey League (NHL) players who were reported to have a sports hernia and who underwent surgery from 2001 to 2008 were identified. Statistics were gathered on the players' previous 2 full seasons and compared with the statistics 2 full seasons after surgery. Data concerning games played, goals, average time on ice, time of productivity, and assists were gathered. Players were divided into 3 groups: group A incorporated all players, group B were players with 6 or fewer seasons of play, and group C consisted of players with 7 or more seasons of play. A control group was chosen to compare player deterioration or improvement over a career; each player selected for the study had a corresponding control player with the same tenure in his career and position during the same years. Forty-three hockey players were identified to have had sports hernia repairs from 2001 to 2008; ultimately, 80% would return to play 2 or more full seasons. Group A had statistically significant decreases in games played, goals scored, and assists. Versus the control group, the decreases in games played and assists were supported. Statistical analysis showed significant decreases in games played, goals scored, assists, and average time on ice the following 2 seasons in group C, which was also seen in comparison with the control group. Group B (16 players) showed only statistical significance in games played versus the control group

Sports injuries in Plus League volleyball players.

Science.gov (United States)

Cieśla, E; Dutkiewicz, R; Mgłosiek, M; Nowak-Starz, G; Markowska, M; Jasiński, P; Dudek, J

2015-06-01

Although physical activity brings a range of lifelong health benefits, it may also lead to injuries that pose a significant threat to health. It is particularly noticeable in people involved in professional sports where sport-related injuries commonly occur and are associated with intense exercise which aims to improve physical fitness. The article attempts to determine incidence of sports injuries reported by Plus League volleyball players, as well as to identify their most common types and causes. The research project involved 90 Plus League volleyball players aged 18-37 with the average age of 25.11 (SD±5.378). A method of diagnostic survey was applied to collect empirical data by means of questionnaire developed by the authors (researchers). The results were statistically analysed and verified with the analysis of variance (ANOVA) and χ2 test at the significance level (or critical P-value) of P≤0.05. Over 87% of the respondents suffered from at least one sport-related injury. In total, 362 injuries occurred, on average 4.02 injuries per one volleyball player. The most common sports injuries involved ankle or talocrural joint (46 injuries), knee and lower leg muscles (30), interphalangeal articulations of fingers (30) as well as shoulder joint. More than half of the injuries (57%) occurred twice or three times. Volleyball players commonly sustain injuries through contact with an opposing player in competition. Sport-specific injuries may also occur due to exhaustion, lack of rest and undertreated injuries. The most common volleyball-related injuries are primarily talocrural joint, hand and shoulder injuries. Common types of injuries that can affect volleyball players include muscles, joints and ligaments injuries, sprains and strains as well as bruises. Most of these injuries are caused by exhaustion, contact with an opposing player during competition and fatigue. The incidence of sport-related injuries seems to be influenced by such factors as somatic

How to know and choose online games: differences between current and potential players.

Science.gov (United States)

Teng, Ching-I; Lo, Shao-Kang; Wang, Pe-Cheng

2007-12-01

This study investigated how different adolescent players acquire game information and the criteria they use in choosing online games and found that (1) current players generally use comprehensive information sources more than potential players do; (2) current players rely on free trials and smooth display of motion graphics as choice criteria more than potential players do; (3) potential players rely on the look of advertisements more than current players do; (4) both current and potential players most likely use word-of-mouth and gaming programs on TV as information sources; and (5) endorser attractiveness is ranked the least important among six choice criteria by both current and potential players.

Fitness Profiles of Elite Portuguese Rugby Union Players

Science.gov (United States)

Vaz, Luís; Morais, Tomaz; Rocha, Henrique; James, Nic

2014-01-01

The aim of this study was to describe the fitness profiles of senior elite Portuguese rugby players. Forty-six senior Portuguese rugby players, classified as backs (n=22; age 26.2±2.8) and forwards (n=24; age 26.7±2.9) were assessed during physical testing sessions carried out for the Portuguese National rugby team. The body composition, maximum strength and anaerobic capacity of players are hypothesized to be important physical characteristics as successful performance in rugby is predicated on the ability to undertake skilled behaviours both quickly and whilst withstanding large forces when in contact situations. No absolute differences were found between the backs and forwards for the speed performance variables although positional differences were found across all speeds when assessed relative to body mass since the forwards were significantly heavier. Coaches and the management team can use this information for monitoring progressive improvements in the physiological capacities of rugby players. These physical characteristics of elite rugby players provide normative profiles for specific positions and should form the basis of developmental programmes for adolescents. PMID:25114750

Fitness Profiles of Elite Portuguese Rugby Union Players

Directory of Open Access Journals (Sweden)

Vaz Luís

2014-07-01

Full Text Available The aim of this study was to describe the fitness profiles of senior elite Portuguese rugby players. Forty-six senior Portuguese rugby players, classified as backs (n=22; age 26.2±2.8 and forwards (n=24; age 26.7±2.9 were assessed during physical testing sessions carried out for the Portuguese National rugby team. The body composition, maximum strength and anaerobic capacity of players are hypothesized to be important physical characteristics as successful performance in rugby is predicated on the ability to undertake skilled behaviours both quickly and whilst withstanding large forces when in contact situations. No absolute differences were found between the backs and forwards for the speed performance variables although positional differences were found across all speeds when assessed relative to body mass since the forwards were significantly heavier. Coaches and the management team can use this information for monitoring progressive improvements in the physiological capacities of rugby players. These physical characteristics of elite rugby players provide normative profiles for specific positions and should form the basis of developmental programmes for adolescents.

Legionnaires' disease from a cooling tower in a community outbreak in Lidköping, Sweden- epidemiological, environmental and microbiological investigation supported by meteorological modelling.

Science.gov (United States)

Ulleryd, Peter; Hugosson, Anna; Allestam, Görel; Bernander, Sverker; Claesson, Berndt E B; Eilertz, Ingrid; Hagaeus, Anne-Christine; Hjorth, Martin; Johansson, Agneta; de Jong, Birgitta; Lindqvist, Anna; Nolskog, Peter; Svensson, Nils

2012-11-21

An outbreak of Legionnaires' Disease took place in the Swedish town Lidköping on Lake Vänern in August 2004 and the number of pneumonia cases at the local hospital increased markedly. As soon as the first patients were diagnosed, health care providers were informed and an outbreak investigation was launched. Classical epidemiological investigation, diagnostic tests, environmental analyses, epidemiological typing and meteorological methods. Thirty-two cases were found. The median age was 62 years (range 36 - 88) and 22 (69%) were males. No common indoor exposure was found. Legionella pneumophila serogroup 1 was found at two industries, each with two cooling towers. In one cooling tower exceptionally high concentrations, 1.2 × 109 cfu/L, were found. Smaller amounts were also found in the other tower of the first industry and in one tower of the second plant. Sero- and genotyping of isolated L. pneumophila serogroup 1 from three patients and epidemiologically suspected environmental strains supported the cooling tower with the high concentration as the source. In all, two L. pneumophila strains were isolated from three culture confirmed cases and both these strains were detected in the cooling tower, but one strain in another cooling tower as well. Meteorological modelling demonstrated probable spread from the most suspected cooling tower towards the town centre and the precise location of four cases that were stray visitors to Lidköping. Classical epidemiological, environmental and microbiological investigation of an LD outbreak can be supported by meteorological modelling methods.The broad competence and cooperation capabilities in the investigation team from different authorities were of paramount importance in stopping this outbreak.

Legionnaires’ disease from a cooling tower in a community outbreak in Lidköping, Sweden- epidemiological, environmental and microbiological investigation supported by meteorological modelling

Science.gov (United States)

2012-01-01

Background An outbreak of Legionnaires’ Disease took place in the Swedish town Lidköping on Lake Vänern in August 2004 and the number of pneumonia cases at the local hospital increased markedly. As soon as the first patients were diagnosed, health care providers were informed and an outbreak investigation was launched. Methods Classical epidemiological investigation, diagnostic tests, environmental analyses, epidemiological typing and meteorological methods. Results Thirty-two cases were found. The median age was 62 years (range 36 – 88) and 22 (69%) were males. No common indoor exposure was found. Legionella pneumophila serogroup 1 was found at two industries, each with two cooling towers. In one cooling tower exceptionally high concentrations, 1.2 × 109 cfu/L, were found. Smaller amounts were also found in the other tower of the first industry and in one tower of the second plant. Sero- and genotyping of isolated L. pneumophila serogroup 1 from three patients and epidemiologically suspected environmental strains supported the cooling tower with the high concentration as the source. In all, two L. pneumophila strains were isolated from three culture confirmed cases and both these strains were detected in the cooling tower, but one strain in another cooling tower as well. Meteorological modelling demonstrated probable spread from the most suspected cooling tower towards the town centre and the precise location of four cases that were stray visitors to Lidköping. Conclusions Classical epidemiological, environmental and microbiological investigation of an LD outbreak can be supported by meteorological modelling methods. The broad competence and cooperation capabilities in the investigation team from different authorities were of paramount importance in stopping this outbreak. PMID:23171054

Legionnaires’ disease from a cooling tower in a community outbreak in Lidköping, Sweden- epidemiological, environmental and microbiological investigation supported by meteorological modelling

Directory of Open Access Journals (Sweden)

Ulleryd Peter

2012-11-01

Full Text Available Abstract Background An outbreak of Legionnaires’ Disease took place in the Swedish town Lidköping on Lake Vänern in August 2004 and the number of pneumonia cases at the local hospital increased markedly. As soon as the first patients were diagnosed, health care providers were informed and an outbreak investigation was launched. Methods Classical epidemiological investigation, diagnostic tests, environmental analyses, epidemiological typing and meteorological methods. Results Thirty-two cases were found. The median age was 62 years (range 36 – 88 and 22 (69% were males. No common indoor exposure was found. Legionella pneumophila serogroup 1 was found at two industries, each with two cooling towers. In one cooling tower exceptionally high concentrations, 1.2 × 109 cfu/L, were found. Smaller amounts were also found in the other tower of the first industry and in one tower of the second plant. Sero- and genotyping of isolated L. pneumophila serogroup 1 from three patients and epidemiologically suspected environmental strains supported the cooling tower with the high concentration as the source. In all, two L. pneumophila strains were isolated from three culture confirmed cases and both these strains were detected in the cooling tower, but one strain in another cooling tower as well. Meteorological modelling demonstrated probable spread from the most suspected cooling tower towards the town centre and the precise location of four cases that were stray visitors to Lidköping. Conclusions Classical epidemiological, environmental and microbiological investigation of an LD outbreak can be supported by meteorological modelling methods. The broad competence and cooperation capabilities in the investigation team from different authorities were of paramount importance in stopping this outbreak.

Cricket club looking for new players

CERN Multimedia

Cricket Club

2016-01-01

The CERN Cricket Club, having lost several key players, has had a very difficult season so far and is desperately in need of new players. Having qualified for the Cricket Switzerland semi-finals for the last two years (unfortunately losing both), this year we are bottom of the Western Pool, having played the last two league matches with only 10 players. If you are interested in playing cricket please join us at net practice, which takes place on the Prevessin site each Thursday evening from 18:00 to around 20:00 (weather permitting) or send me an e-mail (see below). Please have a look at the Cricket Club web site for more information: http://cern.ch/Club-Cricket/ Chris Onions, President of the CERN Cricket Club   (christopher.onions@gmail.com)

Fault Predictive Control of Compact Disk Players

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Wickerhauser, Mladen Victor

2006-01-01

Optical disc players such as CD-players have problems playing certain discs with surface faults like scratches and fingerprints. The problem is to be found in the servo controller which positions the optical pick-up, such that the laser beam is focused on the information track. A scheme handling...

Reklamen som pastiche. Om Dansk Sygeplejeråds annoncekampagne efteråret 1986

Directory of Open Access Journals (Sweden)

Gunhild Agger

1989-08-01

Full Text Available Der er flere og flere medieproducenter, der anser modtagerne for at besidde en vis tekstuel intelligens. Fra detektivpasticher som Dick Spanner og Batman over den konstant genreparodierende "Moon- lighting" (De heldige helte til Poul og Nulles respektløse faktion "I sandhedens Tjeneste" leges der med betydningsdannelsen. Seerne/læserne indbydes til selv at spille ping-pong med billeder og tekst. Gunhild Agger analyserer her denne tendens, sådan som den kom- mer til udtryk inden for reklamen: Anker Jørgensen som James Bond, og kondomer til Prinsessen på Ærten! Mest indgående beskæftiger hun sig med Dansk Sygeplejeråds brug af myten om sygeplejersken i en annoncekampagne op mod overenskomstforhandlingerne i 1987. Gunhild Agger nøjes ikke med en indholdsanalyse af annoncerne, men beskriver hele kampagnen: Dansk Sygeplejeråds hensigter med frem- stødet, kampagnens lancering over for den tre-dobbelte målgruppe, læsernes formodede reception, og kampagnens politiske og holdnings- mæssige effekter.

Development of induction current acquisition device based on ARM

Science.gov (United States)

Ji, Yanju; Liu, Xiyang; Huang, Wanyu; Yao, Jiang; Yuan, Guiyang; Hui, Luan; Guan, Shanshan

2018-03-01

We design an induction current acquisition device based on ARM in order to realize high resolution and high sampling rate of acquisition for the induction current in wire-loop. Considering its characteristics of fast attenuation and small signal amplitude, we use the method of multi-path fusion for noise suppression. In the paper, the design is carried out from three aspects of analog circuit and device selection, independent power supply structure and the electromagnetic interference suppression of high frequency. DMA and ping-pong buffer, as a new data transmission technology, solves real time storage problem of massive data. The performance parameters of ARM acquisition device are tested. The comparison test of ARM acquisition device and cRIO acquisition device is performed at different time constants. The results show that it has 120dB dynamic range, 47kHz bandwidth, 96kHz sampling rate, 5μV the smallest resolution, and its average error value is not more than 4%, which proves the high accuracy and stability of the device.

Sustainability and the Fixed Bed Nuclear Reactor (FBNR

Directory of Open Access Journals (Sweden)

Farhang Sefidvash

2012-08-01

Full Text Available Sustainability as a multifaceted and holistic concept is analyzed. Sustainability involves human relationship with elements such as natural environment, economy, power, governance, education and technology with the ultimate purpose of carrying forward an ever-advancing civilization. The Fixed Bed Nuclear Reactor (FBNR is an innovative, small, simple in design, inherently safe, non-proliferating, and environmentally friendly concept that its deployment can generate energy in a sustainable manner contributing to the prosperity of humanity. The development of FBNR will provide electricity as well as desalinated water through a simple but advanced technology for the developing, as well as developed countries. FBNR is environmentally friendly due to its inherent safety and the convenience of using its spent fuel as the source of radiation for irradiation purposes in agriculture, industry, and medicine. Politically, if a ping pong game brought peace between China and USA, a program of development of FBNR supported by the peace loving international community can become a more mature means to bring peace among certain apparently hostile nations who crave sustainable energy, desalinated water and simple advanced technology.

Multi-static MIMO along track interferometry (ATI)

Science.gov (United States)

Knight, Chad; Deming, Ross; Gunther, Jake

2016-05-01

Along-track interferometry (ATI) has the ability to generate high-quality synthetic aperture radar (SAR) images and concurrently detect and estimate the positions of ground moving target indicators (GMTI) with moderate processing requirements. This paper focuses on several different ATI system configurations, with an emphasis on low-cost configurations employing no active electronic scanned array (AESA). The objective system has two transmit phase centers and four receive phase centers and supports agile adaptive radar behavior. The advantages of multistatic, multiple input multiple output (MIMO) ATI system configurations are explored. The two transmit phase centers can employ a ping-pong configuration to provide the multistatic behavior. For example, they can toggle between an up and down linear frequency modulated (LFM) waveform every other pulse. The four receive apertures are considered in simple linear spatial configurations. Simulated examples are examined to understand the trade space and verify the expected results. Finally, actual results are collected with the Space Dynamics Laboratorys (SDL) FlexSAR system in diverse configurations. The theory, as well as the simulated and actual SAR results, are presented and discussed.

Mechanism of host substrate acetylation by a YopJ family effector.

Science.gov (United States)

Zhang, Zhi-Min; Ma, Ka-Wai; Gao, Linfeng; Hu, Zhenquan; Schwizer, Simon; Ma, Wenbo; Song, Jikui

2017-07-24

The Yersinia outer protein J (YopJ) family of bacterial effectors depends on a novel acetyltransferase domain to acetylate signalling proteins from plant and animal hosts. However, the underlying mechanism is unclear. Here, we report the crystal structures of PopP2, a YopJ effector produced by the plant pathogen Ralstonia solanacearum, in complex with inositol hexaphosphate (InsP 6 ), acetyl-coenzyme A (AcCoA) and/or substrate Resistance to Ralstonia solanacearum 1 (RRS1-R) WRKY . PopP2 recognizes the WRKYGQK motif of RRS1-R WRKY to position a targeted lysine in the active site for acetylation. Importantly, the PopP2-RRS1-R WRKY association is allosterically regulated by InsP 6 binding, suggesting a previously unidentified role of the eukaryote-specific cofactor in substrate interaction. Furthermore, we provide evidence for the reaction intermediate of PopP2-mediated acetylation, an acetyl-cysteine covalent adduct, lending direct support to the 'ping-pong'-like catalytic mechanism proposed for YopJ effectors. Our study provides critical mechanistic insights into the virulence activity of YopJ class of acetyltransferases.

Enzymatic oxidation of rutin by horseradish peroxidase: kinetic mechanism and identification of a dimeric product by LC-Orbitrap mass spectrometry.

Science.gov (United States)

Savic, Sasa; Vojinovic, Katarina; Milenkovic, Sanja; Smelcerovic, Andrija; Lamshoeft, Marc; Petronijevic, Zivomir

2013-12-15

Flavonoid oxidation is important issue in food processing and quality. The kinetic mechanism of enzymatic oxidation of rutin by horseradish peroxidase (HRP) was studied. Rutin oxidation reaction was followed by recording of spectral changes over the time at 360 nm. The studied oxidation is mostly enzymatic and less part non-enzymatic. The reaction with HRP has a higher rate compared with the reaction without of HRP, whereby is part of non-enzymatic reaction about 10% of the total reaction. Kinetic parameters were determined from graphics of linear Michaelis-Menten equation, and it was found that investigated reactions of rutin oxidation by HRP take place in a ping-pong kinetic mechanism. High resolution HPLC-MS analysis of the mixture of oxidized products of rutin revealed the presence of rutin dimer. Because of widely distribution of rutin as well as presence of peroxidases and hydrogen peroxide in fresh foods identification of this enzymatic modification product can be beneficial for foods quality and safety. Copyright © 2013 Elsevier Ltd. All rights reserved.

A word from the DG: LHC commissionning 
enters the home straight

CERN Multimedia

2007-01-01

In an age of blogs there are seemingly no secrets, so by the time Lyn Evans gave his talk on the status of LHC commissioning on 13 September, everyone seemed to know about plug-in modules, beam position monitors and transmitters embedded in ping-pong balls. All the on-line speculation made for interesting reading, and is a clear sign of the growing interest there is in CERN as we approach LHC start-up. We are now entering the final phase of commissioning, and things are going well given the unprecedented complexity of the task in hand. Following the cool-down, powering and warm-up of Sector 7-8 earlier this year, we have learned a great deal about what it means to commission the LHC. There have inevitably been hitches, including the plug-in modules, or PIMs. When the LHC is cooled down, each sector shrinks by about 10 metres in length, and this has to be absorbed by bellows between components and a system of sliding copper fingers (PIM) that ensure electrical connectivity ar...

Compensatory Analysis and Optimization for MADM for Heterogeneous Wireless Network Selection

Directory of Open Access Journals (Sweden)

Jian Zhou

2016-01-01

Full Text Available In the next-generation heterogeneous wireless networks, a mobile terminal with a multi-interface may have network access from different service providers using various technologies. In spite of this heterogeneity, seamless intersystem mobility is a mandatory requirement. One of the major challenges for seamless mobility is the creation of a network selection scheme, which is for users that select an optimal network with best comprehensive performance between different types of networks. However, the optimal network may be not the most reasonable one due to compensation of MADM (Multiple Attribute Decision Making, and the network is called pseudo-optimal network. This paper conducts a performance evaluation of a number of widely used MADM-based methods for network selection that aim to keep the mobile users always best connected anywhere and anytime, where subjective weight and objective weight are all considered. The performance analysis shows that the selection scheme based on MEW (weighted multiplicative method and combination weight can better avoid accessing pseudo-optimal network for balancing network load and reducing ping-pong effect in comparison with three other MADM solutions.

Nanodiamond-Gold Nanocomposites with the Peroxidase-Like Oxidative Catalytic Activity.

Science.gov (United States)

Kim, Min-Chul; Lee, Dukhee; Jeong, Seong Hoon; Lee, Sang-Yup; Kang, Eunah

2016-12-21

Novel nanodiamond-gold nanocomposites (NDAus) are prepared, and their oxidative catalytic activity is examined. Gold nanoparticles are deposited on carboxylated nanodiamonds (NDs) by in situ chemical reduction of gold precursor ions to produce NDAus, which exhibit catalytic activity for the oxidation of o-phenylenediamine in the presence of hydrogen peroxide similarly to a peroxidase. This remarkable catalytic activity is exhibited only by the gold nanoparticle-decorated NDs and is not observed for either Au nanoparticles or NDs separately. Kinetic oxidative catalysis studies show that NDAus exhibit a ping-pong mechanism with an activation energy of 93.3 kJ mol -1 , with the oxidation reaction rate being proportional to the substrate concentration. NDAus retain considerable activity even after several instances of reuse and are compatible with a natural enzyme, allowing the detection of xanthine using cascade catalysis. Association with gold nanoparticles makes NDs a good carbonic catalyst due to charge transfer at the metal-carbon interface and facilitated substrate adsorption. The results of this study suggest that diverse carbonic catalysts can be obtained by interfacial incorporation of various metal/inorganic substances.

GASNet-EX Performance Improvements Due to Specialization for the Cray Aries Network

Energy Technology Data Exchange (ETDEWEB)

Hargrove, Paul H.; Bonachea, Dan

2018-03-27

This document is a deliverable for milestone STPM17-6 of the Exascale Computing Project, delivered by WBS 2.3.1.14. It reports on the improvements in performance observed on Cray XC-series systems due to enhancements made to the GASNet-EX software. These enhancements, known as “specializations”, primarily consist of replacing network-independent implementations of several recently added features with implementations tailored to the Cray Aries network. Performance gains from specialization include (1) Negotiated-Payload Active Messages improve bandwidth of a ping-pong test by up to 14%, (2) Immediate Operations reduce running time of a synthetic benchmark by up to 93%, (3) non-bulk RMA Put bandwidth is increased by up to 32%, (4) Remote Atomic performance is 70% faster than the reference on a point-to-point test and allows a hot-spot test to scale robustly, and (5) non-contiguous RMA interfaces see up to 8.6x speedups for an intra-node benchmark and 26% for inter-node. These improvements are available in the GASNet-EX 2018.3.0 release.

Thermoregulation, Fluid Balance, and Sweat Losses in American Football Players.

Science.gov (United States)

Davis, Jon K; Baker, Lindsay B; Barnes, Kelly; Ungaro, Corey; Stofan, John

2016-10-01

Numerous studies have reported on the thermoregulation and hydration challenges athletes face in team and individual sports during exercise in the heat. Comparatively less research, however, has been conducted on the American Football player. Therefore, the purpose of this article is to review data collected in laboratory and field studies and discuss the thermoregulation, fluid balance, and sweat losses of American Football players. American Football presents a unique challenge to thermoregulation compared with other sports because of the encapsulating nature of the required protective equipment, large body size of players, and preseason practice occurring during the hottest time of year. Epidemiological studies report disproportionately higher rates of exertional heat illness and heat stroke in American Football compared with other sports. Specifically, larger players (e.g., linemen) are at increased risk for heat ailments compared with smaller players (e.g., backs) because of greater body mass index, increased body fat, lower surface area to body mass ratio, lower aerobic capacity, and the stationary nature of the position, which can reduce heat dissipation. A consistent finding across studies is that larger players exhibit higher sweating rates than smaller players. Mean sweating rates from 1.0 to 2.9 L/h have been reported for college and professional American Football players, with several studies reporting 3.0 L/h or more in some larger players. Sweat sodium concentration of American Football players does not seem to differ from that of athletes in other sports; however, given the high volume of sweat loss, the potential for sodium loss is higher in American Football than in other sports. Despite high sweating rates with American Football players, the observed disturbances in fluid balance have generally been mild (mean body mass loss ≤2 %). The majority of field-based studies have been conducted in the northeastern part of the United States, with limited

Pre-training perceived wellness impacts training output in Australian football players.

Science.gov (United States)

Gallo, Tania F; Cormack, Stuart J; Gabbett, Tim J; Lorenzen, Christian H

2016-08-01

The impact of perceived wellness on a range of external load parameters, rating of perceived exertion (RPE) and external load:RPE ratios, was explored during skill-based training in Australian footballers. Fifteen training sessions involving 36 participants were analysed. Each morning before any physical training, players completed a customised perceived wellness questionnaire (sleep quality, fatigue, stress, mood and muscle soreness). Microtechnology devices provided external load (average speed, high-speed running distance, player load and player load slow). Players provided RPE using the modified Borg category-ratio 10 RPE scale. Mixed-effect linear models revealed significant effects of wellness Z-score on player load and player load slow. Effects are reported with 95% confidence limits. A wellness Z-score of -1 corresponded to a -4.9 ± 3.1 and -8.6 ± 3.9% reduction in player load and player load slow, respectively, compared to those without reduced wellness. Small significant effects were also seen in the average speed:RPE and player load slow:RPE models. A wellness Z-score of -1 corresponded to a 0.43 ± 0.38 m·min(-1) and -0.02 ± 0.01 au·min(-1) change in the average speed:RPE and player load slow:RPE ratios, respectively. Magnitude-based analysis revealed that the practical size of the effect of a pre-training perceived wellness Z-score of -1 would have on player load slow was likely negative. The results of this study suggests that monitoring pre-training perceived wellness may provide coaches with information about the intensity of output that can be expected from individual players during a training session.

Prevalence and variance of shoulder injuries in elite collegiate football players.

Science.gov (United States)

Kaplan, Lee D; Flanigan, David C; Norwig, John; Jost, Patrick; Bradley, James

2005-08-01

Shoulder injuries are the fourth most common musculoskeletal injury encountered in American football players. There is little information in the literature on the role of playing position in the type of shoulder injuries seen. There is a high prevalence of shoulder injuries in elite collegiate American football players, with type of injury varying by playing position. Cohort study (prevalence); Level of evidence, 3. A total of 336 elite collegiate American football players were invited to the National Football League Combine for physical testing and medical evaluation. Current and historical data were evaluated for the purpose of this study, and all players underwent radiographic examinations, including plain radiographs and/or magnetic resonance imaging when necessary. All shoulder pathological conditions and shoulder surgical procedures were recorded. Players were categorized by position for the analysis of position-specific trends. Of the players, 50% had a history of shoulder injuries, with a total of 226 shoulder injuries (1.3 injuries per player injured); 56 players (34%) had a total of 73 surgeries. The most common injuries were acromioclavicular separation (41%), anterior instability (20%), rotator cuff injury (12%), clavicle fracture (4%), and posterior instability (4%). The most common surgeries performed were anterior instability reconstruction (48%), Mumford/Weaver-Dunn surgery (15%), posterior instability surgery (10%), and rotator cuff surgery (10%). Shoulder injuries were more common in quarterbacks and defensive backs. Surgery was more common in linebackers or linemen. A history of anterior instability was more common in defensive players, with surgery required 76% of the time. Linemen had more rotator cuff injuries and posterior instability than players in other positions. Shoulder injuries are common injuries in elite collegiate football players, with one-third undergoing surgical procedures. There are definitive trends in the types of injuries

Timing of metamorphism of the Lansang gneiss and implications for left-lateral motion along the Mae Ping (Wang Chao) strike-slip fault, Thailand

Science.gov (United States)

Palin, R. M.; Searle, M. P.; Morley, C. K.; Charusiri, P.; Horstwood, M. S. A.; Roberts, N. M. W.

2013-10-01

The Mae Ping fault (MPF), western Thailand, exhibits dominantly left-lateral strike-slip motion and stretches for >600 km, reportedly branching off the right-lateral Sagaing fault in Myanmar and extending southeast towards Cambodia. Previous studies have suggested that the fault assisted the large-scale extrusion of Sundaland that occurred during the Late Eocene-Early Oligocene, with a geological offset of ˜120-150 km estimated from displaced high-grade gneisses and granites of the Chiang Mai-Lincang belt. Exposures of high-grade orthogneiss in the Lansang National Park, part of this belt, locally contain strong mylonitic textures and are bounded by strike-slip ductile shear zones and brittle faults. Geochronological analysis of monazite from a sample of sheared biotite-K-feldspar orthogneiss suggests two episodes of crystallization, with core regions documenting Th-Pb ages between c. 123 and c. 114 Ma and rim regions documenting a significantly younger age range between c. 45-37 Ma. These data are interpreted to represent possible magmatic protolith emplacement for the Lansang orthogneiss during the Early Cretaceous, with a later episode of metamorphism occurring during the Eocene. Textural relationships provided by in situ analysis suggest that ductile shearing along the MPF occurred during the latter stages of, or after, this metamorphic event. In addition, monazite analyzed from an undeformed garnet-two-mica granite dyke intruding metamorphic units at Bhumipol Lake outside of the Mae Ping shear zone produced a Th-Pb age of 66.2 ± 1.6 Ma. This age is interpreted to date the timing of dyke emplacement, implying that the MPF cuts through earlier formed magmatic and high-grade metamorphic rocks. These new data, when combined with regional mapping and earlier geochronological work, show that neither metamorphism, nor regional cooling, was directly related to strike-slip motion.

Ranking benchmarks of top 100 players in men's professional tennis.

Science.gov (United States)

Reid, Machar; Morris, Craig

2013-01-01

In men's professional tennis, players aspire to hold the top ranking position. On the way to the top spot, reaching the top 100 can be seen as a significant career milestone. National Federations undertake extensive efforts to assist their players to reach the top 100. However, objective data considering reasonable ranking yardsticks for top 100 success in men's professional tennis are lacking. Therefore, it is difficult for National Federations and those involved in player development to give empirical programming advice to young players. By taking a closer look at the ranking history of professional male tennis players, this article tries to provide those involved in player development a more objective basis for decision-making. The 100 names, countries, birthdates and ranking histories of the top 100 players listed in the Association of Tennis Professionals (ATP) at 31 December 2009 were recorded from websites in the public domain. Descriptive statistics were reported for the ranking milestones of interest. Results confirmed the merits of the International Tennis Federation's junior tour with 91% of the top 100 professionals earning a junior ranking, the mean peak of which was 94.1, s=148.9. On average, top 100 professionals achieved their best junior rankings and earned their first ATP point at similar ages, suggesting that players compete on both the junior and professional tours during their transition. Once professionally ranked, players took an average 4.5, s=2.1 years to reach the ATP top 100 at the mean age of 21.5, s=2.6 years, which contrasts with the mean current age of the top 100 of 26.8, s=3.2. The best professional rankings of players born in 1982 or earlier were positively related to the ages at which players earned their first ATP point and then entered the top 100, suggesting that the ages associated with these ranking milestones may have some forecasting potential. Future work should focus on the change in top 100 demographics over time as well

Kinanthropometric and performance characteristics of elite and non-elite female softball players.

Science.gov (United States)

Singh, S; Singh, M; Rathi, B

2013-12-01

The purpose of the present study was to compare the kinanthropometric and performance characteristics of elite and non-elite female softball players. A total forty elite and non-elite level female softball players were selected from the different colleges affiliated to the Guru Nanak Dev University, Amritsar, for the present study. The height of subjects was measured by using the standard anthropometric rod. Weight was measured with portable weighing machine. Widths and diameters of body parts were measured by using digital caliper. Girths and lengths were taken with steel tape. Skinfold thickness measurements were taken using the Slimguide skinfold caliper. All subjects were also assessed for performance tests i.e. vertical jump, 50m sprint, medicine ball throw, 10×4m shuttle run and reaction time. Independent samples t-test reveals that elite female softball players were significantly taller (Psoftball players also had significantly greater biacromial (Psoftball players. The non-elite female softball players were found to have significantly greater thigh circumference (Psoftball players. The non-elite players were also found to have significantly higher percentage body fat (Psoftball players. The elite female softball players had significantly greater kinanthropometric characteristics, body composition and performance characteristics than the non-elite female softball players.

Decreased shoulder function and pain common in recreational badminton players.

Science.gov (United States)

Fahlström, M; Söderman, K

2007-06-01

The aim of this study was to describe the prevalence and consequences of painful conditions in the shoulder region in recreational badminton players. A questionnaire study was performed on 99 players, of whom 57 were also assessed with Constant score. Previous or present pain in the dominant shoulder was reported by 52% of the players. Sixteen percent of the players had on-going shoulder pain associated with badminton play. A majority of these players reported that their training habits were affected by the pain. Total Constant score was lower in the painful shoulders. Furthermore, range of active pain-free shoulder abduction was decreased. However, isometric shoulder strength test showed no differences when compared with pain-free shoulders. Even though the pain caused functional problems, the players were still playing with on-going symptoms. The diagnoses were mostly unknown, although history and clinical tests indicate problems resembling subacromial impingement.

Little League Baseball and Players' Self-Esteem.

Science.gov (United States)

Hawkins, Donna B.; Gruber, Joseph J.

1982-01-01

The effect of a season of little league baseball on the self-esteem of 94 pre-adolescent players was investigated. The Coopersmith Self-esteem Inventory and a newly devised Baseball-Self scale were administered. Significant improvements in players' total Self-esteem, Home-Parents and School-Academic scores were found. (Author/PN)

Incidence of injuries in high school softball and baseball players.

Science.gov (United States)

Shanley, Ellen; Rauh, Mitchell J; Michener, Lori A; Ellenbecker, Todd S

2011-01-01

Participation in high school sports has grown 16.1% over the last decade, but few studies have compared the overall injury risks in girls' softball and boys' baseball. To examine the incidence of injury in high school softball and baseball players. Cohort study. Greenville, South Carolina, high schools. Softball and baseball players (n = 247) from 11 high schools. Injury rates, locations, types; initial or subsequent injury; practice or game setting; positions played; seasonal trends. The overall incidence injury rate was 4.5/1000 athlete-exposures (AEs), with more injuries overall in softball players (5.6/1000 AEs) than in baseball players (4.0/1000 AEs). Baseball players had a higher initial injury rate (75.9/1000 AEs) than softball players (66.4/1000 AEs): rate ratio (RR) = 0.88, 95% confidence interval (CI) = 0.4, 1.7. The initial injury rate was higher than the subsequent injury rate for the overall sample (P softball (P Softball players were more likely to be injured in a game than were baseball players (RR = 1.92, 95% CI = 0.8, 4.3). Most injuries (77%) were mild (3.5/1000 AEs). The upper extremity accounted for the highest proportion of injuries (63.3%). The incidence of injury for pitchers was 37.3% and for position players was 15.3%. The rate of injury was highest during the first month of the season (7.96/1000 AEs). The incidence of injury was low for both softball and baseball. Most injuries were minor and affected the upper extremity. The injury rates were highest in the first month of the season, so prevention strategies should be focused on minimizing injuries and monitoring players early in the season.

Match activities of elite women soccer players at different performance levels

DEFF Research Database (Denmark)

Mohr, Magni; Krustrup, Peter; Andersson, Helena

2008-01-01

, (2) fatigue develops temporarily during and towards the end of a game, and (3) defenders have lower work rates than midfielders and attackers. The difference in high-intensity running between the 2 levels demonstrates the importance of intense intermittent exercise for match performance in women......We sought to study the physical demands and match performance of women soccer players. Nineteen top-class and 15 high-level players were individually videotaped in competitive matches, and time-motion analysis were performed. The players changed locomotor activity >1,300 times in a game...... fewer (P women soccer players (1) top-class international players perform more intervals of high-intensity running than elite players at a lower level...

Performance Outcomes After Metacarpal Fractures in National Basketball Association Players.

Science.gov (United States)

Guss, Michael S; Begly, John P; Ramme, Austin J; Hinds, Richard M; Karia, Raj J; Capo, John T

2016-12-01

Background: The aim was to determine whether players in the National Basketball Association (NBA) who sustain metacarpal fractures demonstrate decreased performance upon return to competition when compared with their performance before injury and that of their control-matched peers. Methods: Data for 32 NBA players with metacarpal fractures incurred over 11 seasons (2002-2003 to 2012-2013) were obtained from injury reports, press releases, and player profiles (www.nba.com and www.basketballreference.com). Player age, body mass index (BMI), position, shooting hand, number of years in the league, and treatment (surgical vs nonsurgical) were recorded. Individual season statistics for the 2 seasons immediately prior to injury and the 2 seasons after injury, including player efficiency rating (PER), were obtained. Thirty-two controls matched by player position, age, and performance statistics were identified. A performance comparison of the cohorts was performed. Results: Mean age at the time of injury was 27 years with an average player BMI of 24. Players had a mean 5.6 seasons of NBA experience prior to injury. There was no significant change in PER when preinjury and postinjury performances were compared. Neither injury to their shooting hand nor operative management of the fracture led to a decrease in performance during the 2 seasons after injury. When compared with matched controls, no significant decline in performance in PER the first season and second season after injury was found. Conclusion: NBA players sustaining metacarpal fractures can reasonably expect to return to their preinjury performance levels following appropriate treatment.

Physiological characteristics of elite and sub-elite badminton players.

Science.gov (United States)

Ooi, Cheong Hwa; Tan, Albert; Ahmad, Azwari; Kwong, Kien Weng; Sompong, Ruji; Ghazali, Khairul Aswadi Mohd; Liew, Swee Lee; Chai, Wen Jin; Thompson, Martin William

2009-12-01

The aims of this study were to establish the physical and physiological attributes of elite and sub-elite Malaysian male badminton players and to determine whether these attributes discriminate elite players from sub-elite players. Measurements and tests of basic anthropometry, explosive power, anaerobic recovery capacity, badminton-specific movement agility, maximum strength, and aerobic capacity were conducted on two occasions, separated by at least one day. The elite (n = 12) and sub-elite (n = 12) players' characteristics were, respectively: mean age 24.6 years (s = 3.7) and 20.5 years (s = 0.7); mass 73.2 kg (s = 7.6) and 62.7 kg (s = 4.2); stature 1.76 m (s = 0.07) and 1.71 m (s = 0.05); body fat 12.5% (s = 4.8) and 9.5% (s = 3.4); estimated VO(2max) 56.9 ml . kg(-1) . min(-1) (s = 3.7) and 59.5 ml . kg(-1) . min(-1) (s = 5.2). The elite players had greater maximum absolute strength in one-repetition maximum bench press (P = 0.015) compared with the sub-elite players. There were significant differences in instantaneous lower body power estimated from vertical jump height between the elite and sub-elite groups (P badminton-specific movement agility tests. Our results show that elite Malaysian male badminton players are taller, heavier, and stronger than their sub-elite counterparts. The test battery, however, did not allow us to discriminate between the elite and sub-elite players, suggesting that at the elite level tactical knowledge, technical skills, and psychological readiness could be of greater importance.

Assessment of Cardiovascular Risk in Collegiate Football Players and Nonathletes

Science.gov (United States)

Dobrosielski, Devon A.; Rosenbaum, Daryl; Wooster, Benjamin M.; Merrill, Michael; Swanson, John; Moore, J. Brian; Brubaker, Peter H.

2010-01-01

Collegiate American football players may be at risk for cardiovascular disease. Objective: To compare cardiovascular disease risk factors and cardiovascular structure and function parameters of football players, stratified by position, to a group of sedentary, nonathletes. Participants: Twenty-six collegiate football players and 13 nonathletes…

Role-player expectations regarding the education of nursing research.

Science.gov (United States)

Zeelie, S C; Bornman, J E; Botes, A C

2003-12-01

This article reports on role player expectations regarding the education of nursing research. The importance of the role player expectations are two-fold: firstly as a factor in the external environment influencing and guiding the formulation phase of the development of standards and secondly, due to the clear indications of problems regarding nursing research in the nursing profession in literature. The role player expectations were elicited using a qualitative, exploratory and contextual design. The role player population included nurse educators, nurses in managerial, clinical and research positions, students and the medical profession. The data was gathered using the naïve sketches and qualitative data analysis was done using Morse & Field's approach (1996:103-107) in combination with Tesch's data analysis approach as cited by Creswell (1994:154-156). Sixty initial categories were narrowed down to six final categories, which are the research learning programme, personnel, students, departmental policies, funding and support systems. The role player expectations were elicited as part of a research study aiming tot develop a self-evaluation system for quality assurance in nursing research and as such, the role player expectations plays a pivotal role in the development of standards for the self-evaluation system.

The players of the photovoltaic sector in France

International Nuclear Information System (INIS)

Houot, G.

2012-01-01

This document reviews 338 players in the French photovoltaic industry. Each player can be the owner of a photovoltaic power plant, or its operator, or the manufacturer of photovoltaic systems, or the manufacturer of components involved in photovoltaic systems, or the equipment wholesaler, or the designer of photovoltaic projects, or the photovoltaic system installer. For each player some pieces of information are gathered: a brief history of the enterprise, the enterprise activity, its staff, its turnover, its main achievements and its prospects. (A.C.)

Monitoring Elite Soccer Players' External Loads Using Real-Time Data.

Science.gov (United States)

Barrett, Steve

2017-11-01

To assess the validity of measuring locomotor activities and PlayerLoad using real-time (RT) data collection during soccer training. Twenty-nine English soccer players participated. Each player wore the same MEMS device (Micromechanical Electrical Systems; S5, Optimeye; CatapultSports, Melbourne, Australia) during 21 training sessions (N = 331 data sets) in the 2015-16 and 2016-17 seasons. An RT receiver (TRX; Catapultsports, Melbourne, Australia) was used to collect the locomotor activities and PlayerLoad data in RT and compared with the postevent downloaded (PED) data. PlayerLoad and locomotor activities (total distance covered; total high-speed running distance covered, >5.5#x00A0;m/s; total sprinting distance covered, >7 m/s; maximum velocity) were analyzed. Correlations were near perfect for all variables analyzed (r = .98-1.00), with a varied level of noise between RT and PED also (0.3-9.7% coefficient of variation). Locomotor activities and PlayerLoad can use both RT and PED concurrently to quantify a player's physical output during a training session. Caution should be taken with higher-velocity-based locomotor activities during RT compared to PED.

Context-dependent player's movement interpretation: application to adaptive game development

Science.gov (United States)

Picard, Francois; Estraillier, Pascal

2010-02-01

Video games are more and more controlled by the real movements of the player. However, the player is constrained by the system devices, imposing a limited vocabulary of actions associated with a set of unnatural movements. To introduce more entertaining video games to players, a component-based architecture is proposed. It has been acknowledged as the starting point for the development of adaptive applications based on the hypothesis of a high level dialogue between the system and the player. The system adaptability relies on interpretation mechanisms of the player behaviors. These behaviors are defined through the representation of the real movements of the player who freely interacts with the 3D elements composing an immersive virtual environment, following a given game scenario. The efficient interpretation of the player movements relies on the introduction in the system of the management of the scene's context. The contextual information not only helps to determine the true meaning of an observed behavior but also makes the system to adapt its processes regarding this interpretation, while managing its hardware and software resources efficiently. A commercial motion capture interface has been enhanced by the elaboration of such a system.

Online Game Elements, Players and the Bond Between Them

OpenAIRE

Schweizer, Sandra

2017-01-01

The results are guidelines for game developers to improve their game design. Through using the guidelines of the paper, developers know how to implement appealing online game elements which appeal to the player and draw them in. The result of the thesis are socializing, achievements and immersion are motivated the player to play online games, as well as the way online games stimulate the player's brain.

Towards Player-Driven Procedural Content Generation

DEFF Research Database (Denmark)

Shaker, Noor

Generating immersive game content is one of the ultimate goals for a game designer. This goal can be achieved taken into account that players’ perceptions of the same game differ according to a number of factors including: players’ personality, playing styles, expertise and cultural background. One...... promising avenue towards optimizing the gameplay experience for individual game players - and thereby attempt to close the affective loop in games - is to automatically tailor the game content in real-time. To realize player-driven procedural content generation one needs to specify the aspects of the game...... that have a key influence on the gameplay experience, identify the relationship between these aspects and player experience and define a mechanism for tailoring the game content to each individual needs. In this dissertation we attempt to address the following research questions towards the aim...

Motivational profile quality players handball

Directory of Open Access Journals (Sweden)

Alfonso Martínez Moreno

2017-06-01

Full Text Available In the sport context, elite category, it is necessary to know all the factors, which in one way or another, affect the athletes throughout the different competitions. The object of study is to know the motivational profile of elite handball players. The sample consisted of 495 players, of whom 47.8% were boys and 52.2% girls, their ages ranged from 12 to 16 years, with an average of 13.8 years (dt = 1.0. Descriptive statistical analyzes of the sample, absolute and relative frequencies were performed for the qualitative variables and for the quantitative values minimum, maximum, mean, standard deviation, Cronbach's alpha. Correlation between variables, with the Pearson correlation coefficient. The MANCOVA test was performed to determine if there were differences between the dimensions of the questionnaire, according to age and years of practice. The results reveal that handball players elite category of the sample object of study have mainly intrinsic motivation, achieving high scores on general motivation, motivation achievement and motivation stimulation. In addition to moderately high values in introjected regulation and very low values in demotivation.

Diagnosis Aerobic Component of Operational Preparedness Skill Players

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Vasylyuk Vasyl

2017-01-01

Full Text Available Considerable importance for the control system, selection and orientation of the players on the stage long-term preparation plays a selection of effective methods of testing the various components of functional fitness athlete for timely, objective information about the players. The use of reliable scientific methods of effective monitoring of the athlete contributes to the further improvement of skills, increase athletic achievements. The purpose of this article is to describe and summarize modern methods of diagnosis and development of aerobic component of operational preparedness players qualifications. This article describes methods that actively and effectively used in leading European football teams. Specifically Yo-Yo test, test Shuttle (beep-test, Bangsbo test, test Hoff-Helgerud, test Conconi, Wingate-test. These tests have a high level of reliability and security mechanisms for assessing aerobic power players.

Noise effects in a three-player prisoner's dilemma quantum game

International Nuclear Information System (INIS)

Ramzan, M; Khan, M K

2008-01-01

We study the three-player prisoner's dilemma game under the effect of decoherence and correlated noise. It is seen that the quantum player is always better off than the classical players. It is also seen that the game's Nash equilibrium does not change in the presence of correlated noise in contradiction to the effect of decoherence in the multiplayer case. Furthermore, it is shown that for maximum correlation the game does not behave as a noiseless game and the quantum player is still better off for all values of the decoherence parameter p which is not possible in the two-player case. In addition, the payoffs reduction due to decoherence is controlled by the correlated noise throughout the course of the game

Race differences in ventricular remodeling and function among college football players.

Science.gov (United States)

Haddad, Francois; Peter, Shanon; Hulme, Olivia; Liang, David; Schnittger, Ingela; Puryear, Josephine; Gomari, Fatemeh A; Finocchiaro, Gherardo; Myers, Jonathan; Froelicher, Victor; Garza, Daniel; Ashley, Euan A

2013-07-01

Athletic training is associated with increases in ventricular mass and volume. Recent studies have shown that left ventricular mass increases proportionally in white athletes with a mass/volume ratio approaching unity. The objective of this study was to compare the proportionality in ventricular remodeling and ventricular function in black versus white National Collegiate Athletic Association Division I football players. From 2008 to 2011, football players at Stanford University underwent cardiovascular screening with a 12-point history and physical examination, electrocardiography, and focused echocardiography. Compared with white players, black players had on average higher left ventricular mass indexes (77 ± 11 vs 71 ± 11 g/m(2), p = 0.009), higher mass/volume ratios (1.18 ± 0.16 vs 1.06 ± 0.09 g/ml, p 1.2. Mass/volume ratio was inversely related to early diastolic tissue Doppler velocity e' (r = -0.50, p football players exhibit more concentric ventricular remodeling, lower early diastolic annular velocities, and increased ventricular voltage compared with white players. Ventricular mass increases proportionally to volume in white players but not in black players. Copyright © 2013 Elsevier Inc. All rights reserved.

Dental Trauma and Mouthguard Usage among Soccer Players in Izmir, Turkey

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Ilhan Uzel

2014-07-01

Full Text Available The aims of this study were to verify the occurrence of dental injuries in 343 amateur Turkish soccer players in İzmir and the level of knowledge of the teams’ soccer players about mouthguards. The soccer players were interviewed to determine the occurrence of dental trauma during soccer and mouthguard usage level. The data were analyzed with descriptive analysis to determine absolute and relative frequencies of answers for each one of the questions. Only 35 (10.2% soccer players reported the occurrence of some type of dental injury during soccer practice. Regarding emergency conducts, approximately 84 players (24.48% answered that replantation could be obtained after teeth avulsion, 23 players (27.38% answered that successful replantation could be obtained within 2 hours immediately after injury, and 60.71% were not able to answer this question. Regarding mouthguard use, 61.8% of soccer players did not know about mouthguards. It was possible to conclude that dental injuries are common during amateur soccer practice and that there is a lack of information in the soccer players related to the emergency conducts and prevention of dental trauma.

[Participation of the piRNA pathway in recruiting a component of RNA polymerase I transcription initiation complex to germline cell nucleoli].

Science.gov (United States)

Fefelova, E A; Stolyarenko, A D; Yakushev, E Y; Gvozdev, V A; Klenov, M S

2017-01-01

Proteins of the Piwi family and short Piwi-interacting RNAs (piRNAs) ensure the protection of the genome from transposable elements. We have previously shown that nuclear Piwi protein tends to concentrate in the nucleoli of the cells of Drosophila melanogaster ovaries. It could be hypothesized that the function of Piwi in the nucleolus is associated with the repression of R1 and R2 retrotransposons inserted into the rDNA cluster. Here, we show that Piwi participates in recruiting Udd protein to nucleoli. Udd is a component of the conserved Selectivity Factor I-like (SL1-like) complex, which is required for transcription initiation by RNA polymerase I. We found that Udd localization depends on Piwi in germline cells, but not in somatic cells of the ovaries. In contrast, knockdowns of the SL1-like components (Udd or TAF1b) do not disrupt Piwi localization. We also observed that the absence of Udd or TAF1b in germline cells, as well as the impairment of Piwi nuclear localization lead to the accumulation of late stage egg chambers in the ovaries, which could be explained by reduced rRNA transcription. These results allow us to propose for the first time a role for Piwi in the nucleolus that is not directly associated with transposable element repression.

Nutrition Status of Young Elite Female German Football Players.

Science.gov (United States)

Braun, Hans; von Andrian-Werburg, Judith; Schänzer, Wilhelm; Thevis, Mario

2018-02-01

To investigate energy intake, energy expenditure, and the nutritional status of young female elite football players using 7-day food and activity records and blood parameters. A total of 56 female elite football players [14.8 (0.7) y] completed the requested food and activity protocols. Misreporting was assessed by the ratio of energy intake to energy expenditure. The food records were analyzed concerning energy and macronutrient and micronutrient intakes, and energy expenditure was calculated using predictive equations. Hematological data and 25-hydroxyvitamin D serum concentrations were determined. Mean energy intake was 2262 (368) kcal/d [40.5 (7.0) kcal/kg/d] and estimated EE averaged 2403 (195) kcal/d. Fifty-three percent of the players exhibited an energy availability nutrition status of some young female football players. As a consequence, strategies have to be developed for a better information and application of sport nutrition practice among young female football players.

Nutrient intake and blood iron status of male collegiate soccer players.

Science.gov (United States)

Noda, Yuka; Iide, Kazuhide; Masuda, Reika; Kishida, Reina; Nagata, Atsumi; Hirakawa, Fumiko; Yoshimura, Yoshitaka; Imamura, Hiroyuki

2009-01-01

The purpose of this study was: 1) to collect baseline data on nutrient intake in order to advise athletes about nutrition practices that might enhance performance, and 2) to evaluate the dietary iron intake and blood iron status of Japanese collegiate soccer players. The subjects were 31 soccer players and 15 controls. Dietary information was obtained with a food frequency questionnaire. The mean carbohydrate (6.9 g.kg-1 BW) and protein (1.3 g/kg) intakes of the soccer players were marginal in comparisons with recommended targets. The mean intakes of calcium, magnesium, vitamin A, B1, B2, and C were lower than the respective Japanese recommended dietary allowances (RDAs) or adequate dietary intakes in the soccer players. The mean intakes of green and other vegetables, milk and dairy products, fruits, and eggs were lower than the recommended targets. Thus, we recommended athletes to increase the intake of these foodstuffs along with slight increase in carbohydrate and lean meat. The mean intake of iron was higher than the respective RDA in the soccer players. A high prevalence of hemolysis (71%) in the soccer players was found. None of the soccer players and controls had anemia. Two soccer players had iron depletion, while none was found in the controls. In those players who had iron deficiency, the training load need to be lowered and/or iron intake may be increased.

SPORTS SHOES PURCHASE INTENTION AMONG MALAYSIAN VOLLEYBALL PLAYERS VS. NON-VOLLEYBALL PLAYERS: A CONCEPTUAL PAPER

Directory of Open Access Journals (Sweden)

GOH PIN SIANG

2013-12-01

Full Text Available The purpose of this study is to advance the understanding of volleyball players’ purchase intention toward sport shoes by investigating the relationship between the independent variables (endorsement, advertising, pricing and electronic word-of-mouth and purchase intention. Descriptive research and causal research will be used as the research design, thus questionnaire and experimentation will be used to obtain data. Primary data in this study is attained by distributing the questionnaire to the Malaysian volleyball players throughout several volleyball tournament venues in Malaysia. The experiment will be conducted by comparing two groups of respondents, including volleyball players and non-volleyball players. This study is limited to several independent variables such as endorsement, advertising, pricing and electronic word-of-mouth. This study is significant for marketers for solving the challenges faced in the sport industry. It also helps to identify consumers’ purchase preferences for sport shoes. The marketer would understand more about their targeted customers’ intentions to purchase, thus the sport industry related with sport marketing in Malaysia might gain more profit.

N-Player Stochastic Differential Games. [control theory

Science.gov (United States)

Varaiya, P.

1974-01-01

Conditions are described which guarantee that the control strategies adopted by N players constitute an efficient solution, an equilibrium, or a core solution. The system dynamics are described by an Ito equation, and all players have perfect information. It was found that when the set of instantaneous joint costs and velocity vectors is convex, the conditions are necessary.

Quantum Two Player Game in Thermal Environment.

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Jerzy Dajka

Full Text Available A two-player quantum game is considered in the presence of thermal decoherence. It is shown how the thermal environment modeled in terms of rigorous Davies approach affects payoffs of the players. The conditions for either beneficial or pernicious effect of decoherence are identified. The general considerations are exemplified by the quantum version of Prisoner Dilemma.

Development of speed qualities of skilled water-polo players

Directory of Open Access Journals (Sweden)

Ostrovsky M.V.

2010-02-01

Full Text Available Swimming preparation of water-polo players is the basic factor of victory of command. There are a few variants of development of speed swimming preparation. The effective pedagogical mean of stimulation of speed qualities is brief exercises at the end of employments after long aerobic work. The purpose of work is an improvement of method of speed preparation of skilled water-polo players. 26 skilled water-polo players (MS -14 and KMS - 12 took part in an experiment in age from 21 to 32 years. The results of correction of structure of training employment are in-process presented in micro cycle. They are directed on the improvement of speed qualities of water-polo players.

Dynamics of tactical behaviour in association football when manipulating players' space of interaction.

Directory of Open Access Journals (Sweden)

Angel Ric

Full Text Available The analysis of positional data in association football allows the spatial distribution of players during matches to be described in order to improve the understanding of tactical-related constraints on the behavioural dynamics of players. The aim of this study was to identify how players' spatial restrictions affected the exploratory tactical behaviour and constrained the perceptual-motor workspace of players in possession of the ball, as well as inter-player passing interactions. Nineteen professional outfield male players were divided into two teams of 10 and 9 players, respectively. The game was played under three spatial constraints: a players were not allowed to move out of their allocated zones, except for the player in possession of the ball; b players were allowed to move to an adjacent zone, and; c non-specific spatial constraints. Positional data was captured using a 5 Hz interpolated GPS tracking system and used to define the configuration states of players for each second in time. The configuration state comprised 37 categories derived from tactical actions, distance from the nearest opponent, distance from the target and movement speed. Notational analysis of players in possession of the ball allowed the mean time of ball possession and the probabilities of passing the ball between players to be calculated. The results revealed that the players' long-term exploratory behaviour decreased and their short-term exploration increased when restricting their space of interaction. Relaxing players' positional constraints seemed to increase the speed of ball flow dynamics. Allowing players to move to an adjacent sub-area increased the probabilities of interaction with the full-back during play build-up. The instability of the coordinative state defined by being free from opponents when players had the ball possession was an invariant feature under all three task constraints. By allowing players to move to adjacent sub-areas, the

Towards Player Adaptivity in a Serious Game for Conflict Resolution

DEFF Research Database (Denmark)

Grappiolo, C.; Cheong, Yun-Gyung; Togelius, J.

2011-01-01

to resolve this type of conflict, the underlying system generates level content automatically which adapts to player experience and behaviour. Preliminary results demonstrate the efficiency of the procedural content generation mechanism in guiding the training of players towards targeted learning objectives.......We present a technology demonstrator for an adaptive serious game for teaching conflict resolution and discuss the research questions associated with the project. The prototype is a single-player 3D mini-game which simulates a resource management conflict scenario. In order to teach the player how...

Game Performance Evaluation in Male Goalball Players

Science.gov (United States)

Molik, Bartosz; Morgulec-Adamowicz, Natalia; Kosmol, Andrzej; Perkowski, Krzysztof; Bednarczuk, Grzegorz; Skowroński, Waldemar; Gomez, Miguel Angel; Koc, Krzysztof; Rutkowska, Izabela; Szyman, Robert J

2015-01-01

Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg), body height (cm), the arm span (cm) and length of the body in the defensive position (cm). The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03) and the sum of good defense (p = 0.04). The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04), the sum of penalty defenses (p = 0.01), and fouls (p = 0.01). The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level. PMID:26834872

Game Performance Evaluation in Male Goalball Players

Directory of Open Access Journals (Sweden)

Molik Bartosz

2015-12-01

Full Text Available Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg, body height (cm, the arm span (cm and length of the body in the defensive position (cm. The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03 and the sum of good defense (p = 0.04. The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04, the sum of penalty defenses (p = 0.01, and fouls (p = 0.01. The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level.

[Eating habits of a group of professional volleyball players].

Science.gov (United States)

Gacek, Maria

2011-01-01

The aim of the research was an analysis of the eating habits of professional volleyball players according to their sex and age. The research has been carried out on a group of 210 men players and women players at the age of 13-25, representatives of sports clubs in Ostrołeka, Myślenice, Bydgoszcz and Warszawa. The research has revealed a limited realisation of rational diets by both men and women players. The most common mistakes made by them include a smaller number of meals during the day than recommended (especially among men), taking up training on empty stomach and insufficient frequency of consumption of dairy products, fish, vegetables and fruit. The research has also revealed excessive consumption of sweets, sweet sparkling drinks and fast food (mainly among men). The examined players to some extent only apply regular strategies of rehydration of their organisms. A high percentage of them do not pay attention to supplementation of liquids after an effort or they drink a lot of liquids at one time. The most frequently chosen drinks were mineral water and isotonic drinks. Supplementation was applied by a small percentage of the players, mainly men, who most often chose vitamins, Izostar, creatine, L-carnitine and HMB.

The health status of retired American football players: Super Bowl III revisited.

Science.gov (United States)

Nicholas, Stephen J; Nicholas, James A; Nicholas, Calvin; Diecchio, Jennifer R; McHugh, Malachy P

2007-10-01

Despite a perception that retired professional football players have poor health, there are little supporting data. Retired football players have poor health compared with age-matched population norms. Cross-sectional study; Level of evidence, 4. Thirty-six of 41 members of the 1969 Super Bowl winning team were contacted 35 years after that event (3 were deceased, and no contact information was available for 2). Players completed an SF-36 health survey and a medical history and football-specific questionnaire. Each player's football-related injury history before 1969 was documented from medical records. It was estimated that there was 80% power to detect a 10% difference in physical and mental health scores between the retired football players (age, 62 +/- 3 y) and population norms (n = 741) at an alpha level of 0.05. SF-36 scores for physical and mental health were not different from age-matched norms (physical health P = .69; mental health P = .49). The most prevalent medical conditions were arthritis (24 of 36 players), hypertension (13 of 36 players), and chronic low back pain (13 of 36 players). SF-36 physical health scores were 21% lower in players with arthritis (P football for 8.3 +/- 3.8 years, and 33 players (94%) reported having had "very fulfilling" (n = 24) or "somewhat fulfilling" (n = 9) careers. These professional football players had long and fulfilling careers with no apparent long-term detrimental effects on physical or mental health scores despite a high prevalence of arthritis.

Evaluating and treating neurobehavioral symptoms in professional American football players

Science.gov (United States)

Possin, Katherine L.; Hess, Christopher P.; Huang, Eric J.; Grinberg, Lea T.; Nolan, Amber L.; Cohn-Sheehy, Brendan I.; Ghosh, Pia M.; Lanata, Serggio; Merrilees, Jennifer; Kramer, Joel H.; Berger, Mitchel S.; Miller, Bruce L.; Yaffe, Kristine; Rabinovici, Gil D.

2015-01-01

Summary In the aftermath of multiple high-profile cases of chronic traumatic encephalopathy (CTE) in professional American football players, physicians in clinical practice are likely to face an increasing number of retired football players seeking evaluation for chronic neurobehavioral symptoms. Guidelines for the evaluation and treatment of these patients are sparse. Clinical criteria for a diagnosis of CTE are under development. The contribution of CTE vs other neuropathologies to neurobehavioral symptoms in these players remains unclear. Here we describe the experience of our academic memory clinic in evaluating and treating a series of 14 self-referred symptomatic players. Our aim is to raise awareness in the neurology community regarding the different clinical phenotypes, idiosyncratic but potentially treatable symptoms, and the spectrum of underlying neuropathologies in these players. PMID:26336629

Prevalent morphometric vertebral fractures in professional male rugby players.

Directory of Open Access Journals (Sweden)

Karen Hind

Full Text Available There is an ongoing concern about the risk of injury to the spine in professional rugby players. The objective of this study was to investigate the prevalence of vertebral fracture using vertebral fracture assessment (VFA dual energy X-ray absorptiometry (DXA imaging in professional male rugby players. Ninety five professional rugby league (n = 52 and union (n = 43 players (n = 95; age 25.9 (SD 4.3 years; BMI: 29.5 (SD 2.9 kg.m2 participated in the research. Each participant received one VFA, and one total body and lumbar spine DXA scan (GE Lunar iDXA. One hundred and twenty vertebral fractures were identified in over half of the sample by VFA. Seventy four were graded mild (grade 1, 40 moderate (grade 2 and 6 severe (grade 3. Multiple vertebral fractures (≥2 were found in 37 players (39%. There were no differences in prevalence between codes, or between forwards and backs (both 1.2 v 1.4; p>0.05. The most common sites of fracture were T8 (n = 23, T9 (n = 18 and T10 (n = 21. The mean (SD lumbar spine bone mineral density Z-score was 2.7 (1.3 indicating high player bone mass in comparison with age- and sex-matched norms. We observed a high number of vertebral fractures using DXA VFA in professional rugby players of both codes. The incidence, aetiology and consequences of vertebral fractures in professional rugby players are unclear, and warrant timely, prospective investigation.

ANTHROPOMETRIC AND PHYSIOLOGICAL CHARACTERISTICS ON INDIAN INTERUNIVERSITY BASKETBALL PLAYERS

Directory of Open Access Journals (Sweden)

Shyamal Koley

2010-08-01

Full Text Available The purpose of this study was two-fold, firstly, to evaluate the anthropometric profile of Indian interuniversity basketball players and, secondly, to search the correlation of body mass index, % body fat, hand grip strength (right dominant and Vo2max,with other anthropometric characteristics studied. Eleven anthropometriccharacteristics, four body composition parameters, two physical and two physiological variables were measured on randomly selected 60 inter-university Indian basketball players (35 males and 25 females aged 18–25 years from Guru Nanak Dev University, Amritsar, Punjab, India with adequate controls (n = 102, 52 males and 50 females. The results indicated that male basketball players were taller (6.63% and heavier (7.31% and female basketball players were slightly taller (0.31% and lighter (3.74% than their control counterparts. One way analysis of variance showed significant (p ≤ .004 - .000 between group differences in all the variables (excepthip circumference between basketball players and controls. In basketball players, significantly positive correlations were found with BMI and other 12 variables, with percent body fat and 7 variables, with right hand grip strength and 12 variables and with Vo2max and other 9 variables, and significantly negative correlationswere found with BMI and other 1 variable (% lean body mass, with percent body fat and other 6 variables, with right hand grip strength and other 2 variables and with Vo2max with other 3 variables. The findings of the present study might be useful in future investigation on player selection, talent identification in the game of basketball and its training program development.

Injury Pattern in Icelandic Elite Male Handball Players.

Science.gov (United States)

Rafnsson, Elis Thor; Valdimarsson, Örnólfur; Sveinsson, Thorarinn; Árnason, Árni

2017-10-10

To examine the incidence, type, location, and severity of injuries in Icelandic elite male handball players and compare across factors like physical characteristics and playing position. Prospective cohort study. The latter part of the preseason and the competitive season of Icelandic male handball. Eleven handball teams (185 players) from the 2 highest divisions in Iceland participated in the study. Six teams (109 players) completed the study. Injuries were recorded by the players under supervision from their team physiotherapists or coaches. Coaches recorded training exposure, and match exposure was obtained from the Icelandic and European Handball Federations. The players directly recorded potential risk factors, such as age, height, weight, previous injuries, and player position. Injury incidence and injury location and number of injury days. Recorded time-loss injuries were 86, of which 53 (62%) were acute and 33 (38%) were due to overuse. The incidence of acute injuries was 15.0 injuries/1000 hours during games and 1.1 injuries/1000 hours during training sessions. No significant difference was found in injury incidence between teams, but number of injury days did differ between teams (P = 0.0006). Acute injuries were most common in knees (26%), ankles (19%), and feet/toes (17%), but overuse injuries occurred in low back/pelvic region (39%), shoulders (21%), and knees (21%). Previous knee injuries were the only potential risk factor found for knee injury. The results indicate a higher rate of overuse injuries in low back/pelvic region and shoulders than in comparable studies.

Physical qualities and activity profiles of sub-elite and recreational Australian football players.

Science.gov (United States)

Stein, Josh G; Gabbett, Tim J; Townshend, Andrew D; Dawson, Brian T

2015-11-01

To investigate the relationship between physical qualities and match activity profiles of recreational Australian football players. Prospective cohort study. Forty players from three recreational Australian football teams (Division One, Two and Three) underwent a battery of fitness tests (vertical jump, 10 and 40 m sprint, 6 m × 30 m repeated sprint test, Yo-Yo intermittent recovery level Two and 2-km time trial). The activity profiles of competitive match-play were quantified using 10-Hz Global Positioning System units. Division One players possessed greater maximum velocity, Yo-Yo level Two and 2-km time trial performances than Division Two and Three players. In addition, Division One players covered greater relative distance, and relative distances at moderate- and high-intensities during match-play than Division Two and Three players. Division Two players had better 2-km time trial performances than Division Three players. Positive associations (P football players competing at a higher level exhibit greater physical qualities and match-play activity profiles than lesser-skilled recreational players. Acceleration and maximum velocity, 2-km time trial and Yo-Yo level Two performances discriminate between players of different playing levels, and are related to physical match performance in recreational Australian football. The development of these qualities is likely to contribute to improved match performance in recreational Australian football players. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Mean Field Games with a Dominating Player

Energy Technology Data Exchange (ETDEWEB)

Bensoussan, A., E-mail: axb046100@utdallas.edu [The University of Texas at Dallas, International Center for Decision and Risk Analysis, Jindal School of Management (United States); Chau, M. H. M., E-mail: michaelchaumanho@gmail.com; Yam, S. C. P., E-mail: scpyam@sta.cuhk.edu.hk [The Chinese University of Hong Kong, Department of Statistics (Hong Kong, People’s Republic of China) (China)

2016-08-15

In this article, we consider mean field games between a dominating player and a group of representative agents, each of which acts similarly and also interacts with each other through a mean field term being substantially influenced by the dominating player. We first provide the general theory and discuss the necessary condition for the optimal controls and equilibrium condition by adopting adjoint equation approach. We then present a special case in the context of linear-quadratic framework, in which a necessary and sufficient condition can be asserted by stochastic maximum principle; we finally establish the sufficient condition that guarantees the unique existence of the equilibrium control. The proof of the convergence result of finite player game to mean field counterpart is provided in Appendix.

Motivation and Sport Injuries in Handball Players

Directory of Open Access Journals (Sweden)

Laguna, María

2010-12-01

Full Text Available The aim of the study was to test whether different levels of motivation are related to the injuries suffered by elite athletes. The sample consists of 80 professional handball players of ASOBAL League, with a mean age of 24.83 years (+ 5.21. Motivation was assessed through the CPRD scale (Gimeno, Buceta & Pérez-Llantada; 1999 and a self-report questionnaire was used to register sports injuries. The results indicate that there is a relationship between motivational levels and the risk for injury. Specifically, players with high motivated players had a greater number of moderate injuries. Although it may seem paradoxical, it is possible that an excessively high motivation leads to overachievement and risk behaviors, which in turn facilitate the appearance of lesions.

Repeated change-of-direction test for collegiate male soccer players.

Science.gov (United States)

Mizuguchi, S; Gray, H; Calabrese, L S; Haff, G G; Sands, W A; Ramsey, M W; Cardinale, M; Stone, M H

2014-08-01

The aim of the study was to investigate the applicability of a repeated change-of-direction (RCoD) test for NCAA Division-I male soccer players. The RCoD test consisted of 5 diagonal direction changes per repetition with a soccer ball to be struck at the end. Each player performed 15 repetitions with approximately 10 seconds to jog back between repetitions. Data were collected in two sessions. In the first session, 13 players were examined for heart rate responses and blood lactate concentrations. In the second session, 22 players were examined for the test's ability to discriminate the primary from secondary players (78.0±16.1 and 10.4±13.3 minutes per match, respectively). Heart rate data were available only from 9 players due to artifacts. The peak heart rate (200.2±6.6 beats∙min-1: 99.9±3.0% maximum) and blood lactate concentration (14.8±2.4 mmol∙L-1 immediately after) resulted in approximately 3.5 and 6.4-fold increases from the resting values, respectively. These values appear comparable to those during intense periods of soccer matches. In addition, the average repetition time of the test was found to discriminate the primary (4.85±0.23 s) from the secondary players (5.10±0.24 s) (P=0.02). The RCoD test appears to induce physiological responses similar to intense periods of soccer matches with respect to heart rate and blood lactate concentration. Players with better average repetition times tend to be those who play major minutes.

Lateral Scapular Slide Test and Scapular Mobility in Volleyball Players

Science.gov (United States)

Ozunlu, Nihan; Tekeli, Hatice; Baltaci, Gul

2011-01-01

Context: The stability of the scapula in relation to the entire moving upper extremity is the key in the throwing sequence. The importance of scapular positioning in volleyball players has been well documented in the literature, but no one has compared scapular positioning between volleyball players and sedentary people. Objective: To compare measurements of scapular mobility obtained using the lateral scapular slide test between volleyball players and sedentary participants without shoulder impairments and to compare changes in scapular mobility in players according to the number of years of sport participation. Design: Cross-sectional study. Setting: University research laboratory. Patients or Other Participants: A total of 121 people at a single university volunteered. Of these, 67 were sedentary (age = 24.3 ± 2.34 years, height = 1.69 ± 0.09 m, mass = 65.1 ± 11.91 kg); 54 were volleyball players from 4 professional teams and were separated into 2 groups according to their years of sport participation. The first group was named young players (n = 31; age = 17.7 ± 2.58 years, height = 1.83 ± 0.10 m, mass = 68.3 ± 12.21 kg, sport participation ≤ 9 years), and the second group was named old players (n = 23; age = 26.9 ± 3.39 years, height = 1.95 ± 4.38 m, mass = 90.7 ± 5.75 kg, sport participation ≥ 10 years). Main Outcome Measure(s): Study participants completed a rating scale for pain and a questionnaire about demographic and shoulder problems. One assessor performed the lateral scapular slide test and additional flexibility measurements around the shoulder girdle. Flexibility (external rotation, internal rotation) and scapular position (1, 2, 3) were compared among groups (young players, old players, sedentary people) and between sides (dominant, nondominant). Results: In sedentary participants, we found differences for position 1 (t66 = 3.327, P = .002), position 2 (t66 = 2.491, P = .004), position 3 (t66 = 2.512, P = .006), and internal rotation

Preferred Leadership Behaviours of Male and Female Badminton Players

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Rajkumar S HARMA

2015-06-01

Full Text Available Pr eferences for specific coaching behaviours of male and female Badminton players were measured by the modified and revised Leadership Scale for Sport. Eighty two (Males=61, Females=21 badminton players were selected from amongst the players representing th eir respective university teams in East - zone Inter - university Badminton (Men/Women tournaments held at Bilaspur (CG. The present investigation noted the statistically significant differences among East - zone Inter - university level male as well as female B adminton player’s preferences for specific coaching behaviour. Differences were not observed between male and female badminton players in all the dimensions together of specific coaching behaviours of preferred leadership. It is recommended that coaches a lign their coaching style to meet the needs of their teams.

Epidemiology of neurodegeneration in American-style professional football players.

Science.gov (United States)

Lehman, Everett J

2013-01-01

The purpose of this article is to review the history of head injuries in relation to American-style football play, summarize recent research that has linked football head injuries to neurodegeneration, and provide a discussion of the next steps for refining the examination of neurodegeneration in football players. For most of the history of football, the focus of media reports and scientific studies on football-related head injuries was on the acute or short-term effects of serious, traumatic head injuries. Beginning about 10 years ago, a growing concern developed among neurologists and researchers about the long-term effects that playing professional football has on the neurologic health of the players. Autopsy-based studies identified a pathologically distinct neurodegenerative disorder, chronic traumatic encephalopathy, among athletes who were known to have experienced concussive and subconcussive blows to the head during their playing careers. Football players have been well represented in these autopsy findings. A mortality study of a large cohort of retired professional football players found a significantly increased risk of death from neurodegeneration. Further analysis found that non-line players were at higher risk than line players, possibly because of an increased risk of concussion. Although the results of the studies reviewed do not establish a cause effect relationship between football-related head injury and neurodegenerative disorders, a growing body of research supports the hypothesis that professional football players are at an increased risk of neurodegeneration. Significant progress has been made in the last few years on detecting and defining the pathology of neurodegenerative diseases. However, less progress has been made on other factors related to the progression of those diseases in football players. This review identifies three areas for further research: (a) quantification of exposure - a consensus is needed on the use of clinically

Characteristics of anteroposterior curvatures of the spine in soccer and futsal players

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Chromik Krystyna

2017-12-01

Full Text Available Purpose. The aim of the study was to determine differences in anteroposterior spine curvatures between futsal players, soccer players, and non-training students. The results may contribute to the development of present-day knowledge of posturometry, and its implementation in training can help reduce the risk of body posture disorders in athletes. Methods. The examined group consisted of 48 athletes and 38 non-training college students. Body posture parameters were measured with the use of Posturometr-S. The normality of distribution was checked with the Shapiro-Wilk test, and the differences between the groups were measured with ANOVA and the Bonferroni post-hoc test. The level of statistical significance was set at p < 0.05. Results. The analysis of angle values revealed the widest and most similar measurements in the group of futsal players and soccer players. The analysis of variance proved statistically significant differences between the soccer players and futsal players (p = 0.003. The difference between the soccer players and non-training students was statistically significant. The highest γ angular value was measured in non-training students, followed by futsal players and soccer players. The statistical analysis revealed significant differences between the non-training students and futsal players, as well as non-training students and soccer players (p < 0.001. Conclusions. A complex assessment of athletes’ body posture is crucial in injury prevention. Training overloads may often lead to disorders of the organ of locomotion and affect the correct body posture in athletes. This, in turn, may result in pains and injuries.

Algorithms for finding optimal paths in network games with p players

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R. Boliac

1997-08-01

Full Text Available We study the problem of finding optimal paths in network games with p players. Some polynomial-time algorithms for finding optimal paths and optimal by Nash strategies of the players in network games with p players are proposed.

Estimation of typhoon rainfall in GaoPing River: A Multivariate Maximum Entropy Method

Science.gov (United States)

Pei-Jui, Wu; Hwa-Lung, Yu

2016-04-01

The heavy rainfall from typhoons is the main factor of the natural disaster in Taiwan, which causes the significant loss of human lives and properties. Statistically average 3.5 typhoons invade Taiwan every year, and the serious typhoon, Morakot in 2009, impacted Taiwan in recorded history. Because the duration, path and intensity of typhoon, also affect the temporal and spatial rainfall type in specific region , finding the characteristics of the typhoon rainfall type is advantageous when we try to estimate the quantity of rainfall. This study developed a rainfall prediction model and can be divided three parts. First, using the EEOF(extended empirical orthogonal function) to classify the typhoon events, and decompose the standard rainfall type of all stations of each typhoon event into the EOF and PC(principal component). So we can classify the typhoon events which vary similarly in temporally and spatially as the similar typhoon types. Next, according to the classification above, we construct the PDF(probability density function) in different space and time by means of using the multivariate maximum entropy from the first to forth moment statistically. Therefore, we can get the probability of each stations of each time. Final we use the BME(Bayesian Maximum Entropy method) to construct the typhoon rainfall prediction model , and to estimate the rainfall for the case of GaoPing river which located in south of Taiwan.This study could be useful for typhoon rainfall predictions in future and suitable to government for the typhoon disaster prevention .

Sex-specific differences in injury types among basketball players

OpenAIRE

Ito E; Iwamoto J; Azuma K; Matsumoto H

2014-01-01

Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball player...

Analyzing In-Game Movements of Soccer Players at Scale

OpenAIRE

Gyarmati, Laszlo; Hefeeda, Mohamed

2016-01-01

It is challenging to get access to datasets related to the physical performance of soccer players. The teams consider such information highly confidential, especially if it covers in-game performance.Hence, most of the analysis and evaluation of the players' performance do not contain much information on the physical aspect of the game, creating a blindspot in performance analysis. We propose a novel method to solve this issue by deriving movement characteristics of soccer players. We use eve...

Profiling in basketball: physical and physiological characteristics of elite players.

Science.gov (United States)

Ostojic, Sergej M; Mazic, Sanja; Dikic, Nenad

2006-11-01

The purpose of this study was to describe structural and functional characteristics of elite Serbian basketball players and to evaluate whether players in different positional roles have different physical and physiological profiles. Five men's basketball teams participated in the study and competed in the professional First National League. Physiological measurements were taken of 60 players during the final week of their preparatory training for competition. According to positional roles, players were categorized as guards (n = 20), forwards (n = 20), and centers (n = 20). Guards were older (p Vertical jump power was significantly higher in centers (p basketball.

Body composition of italian female hockey players

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P Pavan

2009-07-01

Full Text Available Objective: In this work the anthropometric features and the body composition of Italian hockey players, members of the Female National team, were analysed. The purpose of the research was to verify if morphological features could influence the performance of different positional groups. Materials and Methods: Each player was measured for her total and sitting height, weight, 9 skinfolds thickness and bioelectrical impedance analysis. Different equations were used to calculate the Fat% from skinfolds thickness. Results: Average height is not a crucial advantage for this sport. On the contrary the proportion trunk-limb seems to play an important role for the performance of the midfield players. Percentage of body fat of the hockey players was lower than the Fat% of the non-athletes women of the same age. Significant differences were found between Fat% determined by skinfolds thickness and Fat% obtained by bioelectrical impedance analysis. Conclusions: The results of this study indicate that there are significant differences in anthropometric features and in body composition between positional groups, stressing the importance of a specific training program. Keywords: field hockey, bioelectrical impedance, skinfolds thickness, anthropometry.

Hypoconnectivity and Hyperfrontality in Retired American Football Players

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Hampshire, Adam; MacDonald, Alex; Owen, Adrian M.

2013-10-01

Recent research has raised concerns about the long-term neurological consequences of repetitive concussive and sub-concussive injuries in professional players of American Football. Despite this interest, the neural and psychological status of retired players remains unknown. Here, we evaluated the performances and brain activation patterns of retired National Football League players (NFL alumni) relative to controls using an fMRI-optimised neuropsychological test of executive function. Behaviourally, the NFL alumni showed only modest performance deficits on the executive task. By contrast, they showed pronounced hyperactivation and hypoconnectivity of the dorsolateral frontal and frontopolar cortices. Critically, abnormal frontal-lobe function was correlated with the number of times that NFL alumni reported having been removed from play after head injury and was evident in individual players. These results support the hypothesis that NFL alumni have a heightened probability of developing executive dysfunction and suggest that fMRI provides the most sensitive biomarker of the underlying neural abnormality.

Cavum Septum Pellucidum in Retired American Pro-Football Players.

Science.gov (United States)

Gardner, Raquel C; Hess, Christopher P; Brus-Ramer, Marcel; Possin, Katherine L; Cohn-Sheehy, Brendan I; Kramer, Joel H; Berger, Mitchel S; Yaffe, Kristine; Miller, Bruce; Rabinovici, Gil D

2016-01-01

Previous studies report that cavum septum pellucidum (CSP) is frequent among athletes with a history of repeated traumatic brain injury (TBI), such as boxers. Few studies of CSP in athletes, however, have assessed detailed features of the septum pellucidum in a case-control fashion. This is important because prevalence of CSP in the general population varies widely (2% to 85%) between studies. Further, rates of CSP among American pro-football players have not been described previously. We sought to characterize MRI features of the septum pellucidum in a series of retired pro-football players with a history of repeated concussive/subconcussive head traumas compared with controls. We retrospectively assessed retired American pro-football players presenting to our memory clinic with cognitive/behavioral symptoms in whom structural MRI was available with slice thickness ≤2 mm (n=17). Each player was matched to a memory clinic control patient with no history of TBI. Scans were interpreted by raters blinded to clinical information and TBI/football history, who measured CSP grade (0-absent, 1-equivocal, 2-mild, 3-moderate, 4-severe) and length according to a standard protocol. Sixteen of 17 (94%) players had a CSP graded ≥2 compared with 3 of 17 (18%) controls. CSP was significantly higher grade (pfootball players compared with patients without a history of TBI.

Non-invasive Player Experience Estimation from Body Motion and Game Context

DEFF Research Database (Denmark)

Burelli, Paolo; Triantafyllidis, George; Patras, Ioannis

2014-01-01

In this paper, we investigate on the relationship between player experience and body movements in a non-physical 3D computer game. During an experiment, the participants played a series of short game sessions and rated their experience while their body movements were tracked using a depth camera....... The data collected was analysed and a neural network was trained to find the mapping between player body movements, player in- game behaviour and player experience. The results reveal that some aspects of player experience, such as anxiety or challenge, can be detected with high accuracy (up to 81......%). Moreover, taking into account the playing context, the accuracy can be raised up to 86%. Following such a multi-modal approach, it is possible to estimate the player experience in a non-invasive fashion during the game and, based on this information, the game content could be adapted accordingly....

Iliopsoas and Gluteal Muscles Are Asymmetric in Tennis Players but Not in Soccer Players

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Sanchis-Moysi, Joaquin; Idoate, Fernando; Izquierdo, Mikel; Calbet, Jose A. L.; Dorado, Cecilia

2011-01-01

Purpose To determine the volume and degree of asymmetry of iliopsoas (IL) and gluteal muscles (GL) in tennis and soccer players. Methods IL and GL volumes were determined using magnetic resonance imaging (MRI) in male professional tennis (TP) and soccer players (SP), and in non-active control subjects (CG) (n = 8, 15 and 6, respectively). Results The dominant and non-dominant IL were hypertrophied in TP (24 and 36%, respectively, Psoccer players had similar volumes in both sides (P = 0.87). The degree of side-to-side asymmetry decreased linearly from the first lumbar disc to the pubic symphysis in TP (r = −0.97, PSoccer and CG had similar GL volumes in both sides (P = 0.11 and P = 0.19, for the dominant and contralateral GL, respectively). GL was asymmetrically hypertrophied in TP. The non-dominant GL volume was 20% greater in TP than in CG (Psoccer is associated to a symmetric hypertrophy of IL. Gluteal muscles are asymmetrically hypertrophied in TP, while SP display a similar size to that observed in controls. It remains to be determined whether the different patterns of IL and GL hypertrophy may influence the risk of injury. PMID:21829539

Body Image Amongst Elite Rugby Union Players.

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Gibson, Claire; Hindle, Chloe; McLay-Cooke, Rebecca; Slater, Joanne; Brown, Rachel; Smith, Brett; Baker, Dane; Healey, Philip; Black, Katherine

2017-11-16

There is limited information on the risk of eating disorders and body image of elite male athletes. However, research suggests there are some athletes who have poor body image and they may be at increased risk of developing eating disorders. Therefore, the current study investigated risk of eating disorders, body image, and the relationship with age, in elite rugby union players during their pre-season training period.This cross-sectional study was undertaken at the start of the pre-season amongst elite rugby union players in New Zealand. Twenty-six professional rugby union players completed a 49-item questionnaire on body image and disordered eating. A 'body image score' was calculated from questionnaire subscales including 'drive for thinness', 'bulimia' and 'body dissatisfaction', with total scores above twenty indicative of poor body image.Body image scores varied from 8-39 out of a possible 0-100. Disordered eating behaviours were reported, including binge eating at least once a week (15%, n=4/26), pathogenic weight control use (4%, n=1/26) and avoidance of certain foods (77%, n=20/26). There was a statistically significant inverse association between the bulimia subscale and age (P = 0.034).At the start of the pre-season training period, many elite rugby union players experience disturbances in body image. The prevalence of disordered eating behaviours is of concern, and needs to be minimised due to the negative impact on health and performance. A focus on assessment and education of younger male rugby players may be required in order to reduce disordered eating patterns.

Kinetic studies of Chromobacterium viscosum lipase in AOT water in oil microemulsions and gelatin microemulsion-based organogels.

Science.gov (United States)

Jenta, T R; Batts, G; Rees, G D; Robinson, B H

1997-06-05

Kinetic studies have shown that octyl decanoate synthesis by Chromobacterium viscosum (CV) lipase in sodium bis-2-(ethylhexyl) sulfosuccinate (AOT) water in oil (w/o) microemulsions occurs via the nonsequential (ping-pong) bi bi mechanism. There was evidence of single substrate inhibition by decanoic acid at high concentrations. Initial rate data yielded estimates for acid and alcohol Michaelis constants of ca. 10(-1) mol dm(-3) and a maximum rate under saturation conditions of ca. 10(-3) mol dm(-3) s(-1) for a lipase concentration of 0.36 mg cm(-3). CV lipase immobilized in AOT microemulsion-based organogels (MBGs) was also found to catalyze the synthesis of octyl decanoate according to the ping-pong bi bi mechanism. Reaction rates were similar in the free and immobilized systems under comparable conditions. Initial rates at saturating (but noninhibiting) substrate concentrations were first order with respect to CV lipase concentration in both w/o microemulsions and the MBG/oil systems. Gradients yielded an apparent k(cat) = 4.4 x 10(-4) mol g(-1) s(-1) in the case of w/o microemulsions, and 6.1 x 10(-4) mol g(-1) s(-1) for CV lipase immobilized in the MBGs. A third system comprising w/o microemulsions containing substrates and gelatin at concentrations comparable to those employed in the MBG formulations, provided a useful link between the conventional liquid microemulsion medium and the solid organogels. The nongelation of these intermediate systems stems from the early inclusion of substrate during a modified preparative protocol. The presence of substrate appears to prevent the development of a percolated microstructure that is thought to be a prerequisite for MBG formation. FT-NMR was employed as a semicontinuous in situ assay procedure. The apparent activity expressed by CV lipase in compositionally equivalent liquid and solid phase gelatin-containing systems was similar. An apparent activation energy of 24 +/- 2 kJ mol(-1) was determined by (1)H-NMR for

Effect of Core Training on 16 Year-Old Soccer Players

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Afyon, Yakup Akif

2014-01-01

Core trainings have been widely used by trainers recently in order to improve performance of soccer players. In this context, the aim of this study is to examine the effect of core training on some motoric capabilities of 16 years old soccer players. Thirty certified soccer players who were 16 years old from B.B. Bodrumspor Club in 2013-2014…

Estimation of player's preference for cooperative RPGs using multi-strategy Monte-Carlo method

OpenAIRE

Sato, Naoyuki; Ikeda, Kokolo; Wada, Takayuki

2015-01-01

In many video games such as role playing games(RPGs) or sports games, computer players act not only as the opponents of the human player but also as team-mates. But computer players as team-mates often behave in a way that human players do not expect, and such mismatches cause bigger dissatisfaction than in the case of computer players as opponents. One of the reasons for such mismatches is that there are several types of sub-goals or play-styles in these games and the Ai players act without ...

Energy and macronutrient intakes of professional football (soccer) players.

OpenAIRE

Maughan, R J

1997-01-01

OBJECTIVE: To examine the dietary habits of professional soccer players at two Scottish Premier League clubs during the competitive season. METHODS: A study of the dietary intake of 51 professional soccer players with two different clubs was carried out by the seven day weighed intake method. RESULTS: Physical characteristics of the two groups of players were similar, with only small differences in age and body mass but no difference in height and body fat. Mean (SD) daily energy intake for c...

Prevalence of Os Styloideum in National Hockey League Players

Science.gov (United States)

Greditzer, Harry G.; Hutchinson, Ian D.; Geannette, Christian S.; Hotchkiss, Robert N.; Kelly, Bryan T.; Potter, Hollis G.

2017-01-01

Background: Os styloideum describes an accessory carpal ossicle between the trapezoid, the capitate, and the second and third metacarpals. Injuries to this tissue have been described as part of the carpal boss syndrome. While the etiology of os styloideum remains uncertain, it may represent a physiologic response to altered loading forces in the wrist, similar to the development of cam-type deformity in the hips of ice hockey players or the Bennett lesion in the shoulders of baseball pitchers. Hypothesis: Professional hockey players will have a higher prevalence of os styloideum compared with the general population. Study Design: Case series. Level of Evidence: Level 4. Methods: A retrospective review of 16 professional hockey players from 4 different National Hockey League (NHL) teams who underwent unilateral imaging of the wrist was performed. Seventeen wrists were reviewed for the presence of os styloideum. Results: Thirteen of 16 players (81%) had an os styloideum, representing an increased prevalence compared with the general population. Previous clinical and cadaveric studies estimated a general prevalence of up to 19% (P < 0.001). For the 10 players who had their leading wrist scanned, 9 had an os styloideum (90%). Ten of 11 (91%) players demonstrated a bone marrow edema pattern within the metacarpal and the os styloideum on magnetic resonance imaging. There was no significant association between the presence of an os styloideum and the player’s position, leading wrist, or years in the league. Conclusion: There appears to be an increased prevalence of os styloideum among NHL players, and team physicians should consider this finding while formulating a differential diagnosis for dorsal wrist pain. Clinical Relevance: This study identified NHL players as having an increased prevalence of os styloideum compared with the general population. By doing so, these findings represent an opportunity to enhance our understanding of the etiology, clinical significance

Three-player conflicting interest games and nonlocality

Science.gov (United States)

Bolonek-Lasoń, Katarzyna

2017-08-01

We outline the general construction of three-player games with incomplete information which fulfil the following conditions: (i) symmetry with respect to the permutations of players; (ii) the existence of an upper bound for total payoff resulting from Bell inequalities; (iii) the existence of both fair and unfair Nash equilibria saturating this bound. Conditions (i)-(iii) imply that we are dealing with conflicting interest games. An explicit example of such a game is given. A quantum counterpart of this game is considered. It is obtained by keeping the same utilities but replacing classical advisor by a quantum one. It is shown that the quantum game possesses only fair equilibria with strictly higher payoffs than in the classical case. This implies that quantum nonlocality can be used to resolve the conflict between the players.

Shoulder pain -- a common problem in world-class badminton players.

Science.gov (United States)

Fahlström, Martin; Yeap, Joo Seng; Alfredson, Håkan; Söderman, Kerstin

2006-06-01

Badminton is a sport that requires a lot of over-shoulder motion, with the shoulder in abduction/external rotation. This questionnaire study on 188 international top-level badminton players during the World Mixed Team Championships showed that previous or present shoulder pain on the dominant side was reported by 52% of the players. Previous shoulder pain was reported by 37% of the players and on-going shoulder pain by 20% of the players. There were no significant differences in the prevalence of shoulder pain between men and women. The majority of the shoulder pain had started gradually. The pain was usually associated with shoulder activity, and stiffness was a common, associated symptom. Furthermore, the shoulder pain was associated with consequences such as sleeping disturbances, changes in training and competition habits, and it also affected activities of daily living. The majority of the players had sought medical advice and had been given different kinds of treatment. The study showed that shoulder pain is a common and significant problem in world-class badminton players, and the consequences are most likely of importance for their training and playing capacity.

Nutrient consumption pattern of male soccer players in Shiraz/Iran

Directory of Open Access Journals (Sweden)

Saeed Najafpour Bushehry

2003-09-01

Full Text Available Exercise and nutrition have a significant impact on health. To evaluate nutrient consumption pattern of soccer players in city of Shiraz, 323 players were selected by proportional multi-stage cluster random sampling from 11 clubs in Shiraz. Anthropometric indices, socioeconomic status, 24 hours dietary recall and food frequency data were collected. Protein, carbohydrate and fat intake of the players were 73.73 gr (10.8%, 493.3 gr (72.4% and 50.8 gr (16.7%, respectively. Calcium (689.6 mg, phosphorus (734.4 mg, iron (20.3 mg, vitamin B1 (2 mg, vitamin B2 (1.6 mg, vitamin C (107.5 mg and vitamin A (962.4 mcg RE intake were lower than the desirable levels. The mean energy consumption of the players was 2723 Kcal per day. In conclusion, protein and micronutrients intakes are not desirable in Iranian soccer players in Shiraz.

Communication aspects of a three-player Prisoner's Dilemma quantum game

International Nuclear Information System (INIS)

Ramzan, M; Khan, M K

2009-01-01

We present a quantization scheme for a three-player Prisoner's Dilemma game. It is shown that entanglement plays a dominant role in the three-player quantum game. Four different types of payoffs are identified on the basis of different combinations of initial state and measurement basis entanglement parameters. A relation among these different payoffs is also established. We also study the communication aspects of the three-player game. By exploiting different combinations of initial state and measurement basis entanglement parameters, we establish a relationship for the information shared among the parties. It is seen that the strategies of the players act as carriers of information in quantum games

A dynamic game of a transboundary pollutant with asymmetric players

International Nuclear Information System (INIS)

Martin, W.E.; Patrick, R.H.; Tolwinski, B.

1993-01-01

Modeling transboundary pollutants in a dynamic game framework provides a foundation for analyzing the impact of various policy options. The focus of this analysis is on the results of a tax/subsidy scheme used to address the transboundary problem of global climate change. A nonzero-sum dynamic game with asymmetric players is used to evaluate the policy impact of the tax/subsidy scheme on the respective player's value functions and strategies as determined by a Nash equilibrium feedback solution. The asymmetry of the players is reflected in their respective attitudes toward global climate change with one player benefiting from the change and the other losing. 17 refs., 5 tabs

Managing player load in professional rugby union: a review of current knowledge and practices.

Science.gov (United States)

Quarrie, Kenneth L; Raftery, Martin; Blackie, Josh; Cook, Christian J; Fuller, Colin W; Gabbett, Tim J; Gray, Andrew J; Gill, Nicholas; Hennessy, Liam; Kemp, Simon; Lambert, Mike; Nichol, Rob; Mellalieu, Stephen D; Piscione, Julien; Stadelmann, Jörg; Tucker, Ross

2017-03-01

The loads to which professional rugby players are subjected has been identified as a concern by coaches, players and administrators. In November 2014, World Rugby commissioned an expert group to identify the physical demands and non-physical load issues associated with participation in professional rugby. To describe the current state of knowledge about the loads encountered by professional rugby players and the implications for their physical and mental health. The group defined 'load' as it relates to professional rugby players as the total stressors and demands applied to the players. In the 2013-2014 seasons, 40% of professional players appeared in 20 matches or more, and 5% of players appeared in 30 matches or more. Matches account for ∼5-11% of exposure to rugby-related activities (matches, team and individual training sessions) during professional competitions. The match injury rate is about 27 times higher than that in training. The working group surmised that players entering a new level of play, players with unresolved previous injuries, players who are relatively older and players who are subjected to rapid increases in load are probably at increased risk of injury. A mix of 'objective' and 'subjective' measures in conjunction with effective communication among team staff and between staff and players was held to be the best approach to monitoring and managing player loads. While comprehensive monitoring holds promise for individually addressing player loads, it brings with it ethical and legal responsibilities that rugby organisations need to address to ensure that players' personal information is adequately protected. Administrators, broadcasters, team owners, team staff and the players themselves have important roles in balancing the desire to have the 'best players' on the field with the ongoing health of players. In contrast, the coaching, fitness and medical staff exert significant control over the activities, duration and intensity of training

Nutrition review for hockey players : enhancing performance through nutrition

OpenAIRE

Bursich, Chris

2011-01-01

With the advancement of sports medicine in the past decade, hockey players all over the world are always trying to find a competitive edge through nutritional education and proper eating. It is very common to find young junior players looking to make the jump into the professional game always trying to find ways to get bigger and add lean muscle mass, likewise, there are always players looking to drop a few pounds while keeping their muscle mass. Research has proven that through proper educat...

Authoring of Adaptive Single-Player Educational Games

OpenAIRE

Mehm, Florian

2013-01-01

Digital Educational Games, as one of the most important application areas of Serious Games, combine positive properties of digital games, such as strong motivation for players and inherent learning processes, with educational methods and technologies. Adaptive algorithms allow such games to be aligned automatically to the needs of different players, thereby increasing the learning efficacy. However, educational games are among the most complex game production endeavors, since they are often f...

Physical Fitness Qualities of Professional Rugby League Football Players: Determination of Positional Differences.

Science.gov (United States)

Meir, Rudi; Newton, Robert; Curtis, Edgar; Fardell, Matthew; Butler, Benjamin

2001-01-01

Australian and English professional rugby players completed various physical fitness performance tests to determine differences when grouping players into three different rugby positional categories. Results found minimal differences in test scores on the basis of players' specific positions on a team, however, when players were grouped according…

Early Sport Specialization: Effectiveness and Risk of Injury in Professional Baseball Players.

Science.gov (United States)

Wilhelm, Andrew; Choi, Changryol; Deitch, John

2017-09-01

The rate of early sport specialization in professional baseball players is unknown. To report the incidence and age of sport specialization in current professional baseball players and the impact of early specialization on the frequency of serious injuries sustained during the players' careers. We also queried participants about when serious injuries occurred, the players' current position on the field, and their opinions regarding the need for young athletes to specialize early to play at the professional level. Descriptive epidemiological study. A total of 102 current professional baseball players anonymously completed a 7-question written survey. Early sport specialization was defined as "single-sport participation prior to high school." Injury was defined as "a serious injury or surgery that required the player to refrain from sports (baseball) for an entire year." Chi-square tests were used to investigate the risk of injury in those who specialized early in baseball versus those who did not. Independent-sample t tests were used to compare injury rates based on current player position. Fifty (48%) baseball players specialized early. The mean age at initiation of sport specialization was 8.91 years (SD, 3.7 years). Those who specialized early reported more serious injuries (mean, 0.54; SD, 0.838) during their professional baseball career than those who did not (mean, 0.23; SD, 0.425) ( P = .044). Finally, 63.4% of the queried players believed that early sport specialization was not required to play professional baseball. Our study demonstrated a statistically significant higher rate of serious injury during a baseball player's professional career in those players who specialized early. Most current professional baseball players surveyed believed that sport specialization was not required prior to high school to master the skills needed to play at the professional level. Our findings demonstrate an increased incidence of serious injuries in professional baseball

Plasma and erythrocyte phospholipid fatty acid profile in professional basketball and football players.

Science.gov (United States)

Tepsic, Jasna; Vucic, Vesna; Arsic, Aleksandra; Blazencic-Mladenovic, Vera; Mazic, Sanja; Glibetic, Marija

2009-10-01

The effect of intensive long-term physical activity on phospholipid fatty acid (FA) composition has not been studied thoroughly. We determined plasma and erythrocyte phospholipid FA status of professional basketball and football players. Our results showed differences in plasma FA profile not only between sportsmen and sedentary subjects, but also between two groups of sportsmen. Plasma FA profile in basketball players showed significantly higher proportion of n-6 FA (20:3, 20:4, and 22:4) and total polyunsaturated FA (PUFA) than controls, while football players had higher palmitoleic acid (16:1) than basketball players and controls. Total PUFA and 22:4 were also higher in basketball than in football players. Erythrocyte FA profile showed no differences between football players and controls. However, basketball players had higher proportion of 18:0 than controls, higher saturated FA and lower 18:2 than two other groups, and higher 22:4 than football players. These findings suggest that long-term intensive exercise and type of sport influence FA profile.

MEANING TO BE VOLLEYBALL PLAYER IN CAREER TRANSITION PHASE

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Adriana Justino

2016-09-01

Full Text Available The objective of this study is to assess the meaning of being that a volleyball player for the under-19 players who are experiencing a transition in their in career. Sixteen male players aged 17 and 18 were evaluated, by being asked the triggering question “What does being a volleyball player mean to you?” The analysis of the discourses was carried out according to the procedures recommended by Miles & Huberman (2004. Four response categories resulted: psychoemotional and behavioral skills, emotions in sport, recognition and financial return, skills as an athlete/player. The athletes showed that the meaning of sport lies especially in the passion for practice, but also, in the improving of their tactics and techniques, in the development of psychoemotional and behavioral skills, in the professional recognition and, to a lesser degree, in the financial aspect. Most athletes state they intend to continue in the juvenile sports categories, therefore, understanding the meaning of this activity in their life can be the key to the elaboration of a plan of psychological preparation whose aim is to provide support to their needs in this moment of professional choice.

ANTHROPOMETRIC AND MOTOR CHARACTERISTICS IN VOLLEYBALL AND BASKETBALL PLAYERS

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Enver Tahiraj

2011-09-01

Full Text Available The purpose of this study is the morphological and motor status players for both teams, and then based on the results of anthropometric and motor status of this work can also do a comparative analysis between these two sports, volleyball and basketball. Therefore, the present study is in the results (achieved of the differences and their special achievement and to skills top players. In this research, we have participation 30 players (15 for each team volleyball and basketball, the teams is from Pristina. It should be noted that all players are fully able to follow regular exercise in their clubs. Those two clubs in Pristina, have the training five days a week, the clubs are in super league and the current champion in country. We as a coach interesed about the comparisons and differences of these two sports for anthropometric and motor characteristics, and in these sports, in those two sports players have a special that is characterized by height body and explosive power. We think, that this research work serves as a continuation of the way and further research on these two sports that have a significant increase from the psycho-physical and anthropometric aspects

Countermovement-Jump-Phase Characteristics of Senior and Academy Rugby League Players.

Science.gov (United States)

McMahon, John J; Murphy, Shannon; Rej, Sophie J E; Comfort, Paul

2017-07-01

Gross measures of countermovement-jump (CMJ) performance are commonly used to track maturational changes in neuromuscular function in rugby league (RL). The purpose of this study was to conduct both a gross and a more detailed temporal-phase analysis of the CMJ performances of senior and academy RL players, to provide greater insight into how neuromuscular function differs between these groups. Twenty senior and 14 academy (under-19) male RL players performed 3 maximal-effort CMJs on a force platform, with forward dynamics subsequently employed to allow gross performance measures and entire kinetic- and kinematic-time curves to be compared between groups. Jump height (JH), reactive strength index modified, concentric displacement, and relative concentric impulse (C-IMP) were the only gross measures that were greater for senior players (d = 0.58-0.91) than for academy players. The relative force- and displacement-time curves were similar between groups, but the relative power- and velocity-time curves were greater (d = 0.59-0.97) for the senior players at 94-96% and 89-100% of the total movement time, respectively. The CMJ distinguished between senior and academy RL players, with seniors demonstrating greater JH through applying a larger C-IMP and thus achieving greater velocity throughout the majority of the concentric phase and at takeoff. Therefore, academy RL players should train to improve triple (ie, ankle, knee, and hip) extension velocity during the CMJ to bring their JH scores in line with those attained by senior players.

Video game players show more precise multisensory temporal processing abilities.

Science.gov (United States)

Donohue, Sarah E; Woldorff, Marty G; Mitroff, Stephen R

2010-05-01

Recent research has demonstrated enhanced visual attention and visual perception in individuals with extensive experience playing action video games. These benefits manifest in several realms, but much remains unknown about the ways in which video game experience alters perception and cognition. In the present study, we examined whether video game players' benefits generalize beyond vision to multisensory processing by presenting auditory and visual stimuli within a short temporal window to video game players and non-video game players. Participants performed two discrimination tasks, both of which revealed benefits for video game players: In a simultaneity judgment task, video game players were better able to distinguish whether simple visual and auditory stimuli occurred at the same moment or slightly offset in time, and in a temporal-order judgment task, they revealed an enhanced ability to determine the temporal sequence of multisensory stimuli. These results suggest that people with extensive experience playing video games display benefits that extend beyond the visual modality to also impact multisensory processing.

Special considerations in the medical management of professional basketball players.

Science.gov (United States)

Steingard, S A

1993-04-01

The NBA basketball players are among the finest athletes in the world. That along with the increased popularity of the NBA has put a premium on the health of the players. The course of the season puts tremendous stress and strain on players. As medical illnesses occur, the physician may feel increased pressure to put the ill player back into the line-up. One cannot let the pressure for the player to return to activity interfere with good medical practice. At times, it is difficult to allow for the natural course of an illness, however, as discussed in this article, sometimes this is exactly what needs to be done. The temptation to overtreat is also seen in some team physicians. This too must be avoided. Along with proper treatment, there is the need for education of the athletes both in social interactions and in diet and life-style. Then we, as team physicians, can sit back and enjoy the performance on the court.

Player-Specific Conflict Handling Ontology

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Charline Hondrou

2014-09-01

Full Text Available This paper presents an ontology that leads the player of a serious game - regarding conflict handling - to the educative experience from which they will benefit the most. It provides a clearly defined tree of axioms that maps the player’s visually manifested affective cues and emotional stimuli from the serious game to conflict handling styles and proposes interventions. The importance of this ontology lies in the fact that it promotes natural interaction (non-invasive methods and at the same time makes the game as player-specific as it can be for its educational goal. It is an ontology that can be adapted to different educational theories and serve various educational purposes.

The architecture of the chess player's brain.

Science.gov (United States)

Hänggi, Jürgen; Brütsch, Karin; Siegel, Adrian M; Jäncke, Lutz

2014-09-01

The game of chess can be seen as a typical example for an expertise task requiring domain-specific training and experience. Despite intensive behavioural studies the neural underpinnings of chess performance and expertise are not entirely understood. A few functional neuroimaging studies have shown that expert chess players recruit different psychological functions and activate different brain areas while they are engaged in chess-related activities. Based on this functional literature, we predicted to find morphological differences in a network comprised by parietal and frontal areas and especially the occipito-temporal junction (OTJ), fusiform gyrus, and caudate nucleus. Twenty expert chess players and 20 control subjects were investigated using voxel-based and surface-based morphometry as well as diffusion tensor imaging. Grey matter volume and cortical thickness were reduced in chess players compared with those of control men in the OTJ and precunei. The volumes of both caudate nuclei were not different between groups, but correlated inversely with the years of chess playing experience. Mean diffusivity was increased in chess players compared with that of controls in the left superior longitudinal fasciculus and the Elo score (a chess tournament ranking) was inversely related to mean diffusivity within the right superior longitudinal fasciculus. To the best of our knowledge we showed for the first time that there are specific differences in grey and white matter morphology between chess players and control subjects in brain regions associated with cognitive functions important for playing chess. Whether these anatomical alterations are the cause or consequence of the intensive and long-term chess training and practice remains to be shown in future studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nutritional Practices of National Female Soccer Players: Analysis and Recommendations

Science.gov (United States)

Martin, Louise; Lambeth, Anneliese; Scott, Dawn

2006-01-01

The aim of the study was to establish the nutritional practices and activity patterns of elite female soccer players. The nutritional intake of 16 female England Soccer players was self-reported over a seven-day period. Participants were provided with written and verbal guidelines for the completion of the diaries. Training details were also recorded, and used in combination with BMR predictions to calculate daily energy expenditure. Energy, macronutrient and micronutrient intakes were determined using DietMaster 4.0 software. Results suggest that energy intake was low (1904 ± 366.3 kcal) in relation to previous recommendations for soccer players. Energy expenditure (2153.5 ± 596.2 kcal) was not significantly different (p > 0.05) from intake, suggesting energy balance was achieved. Carbohydrate (53.8 ± 6.8%), protein (16.8 ± 2.1%) and fat (28.8 ± 6.6%) intakes were in line with recommendations. Fluid intake (2466 ± 1350.5ml·day-1) was sufficient to meet baseline recommendations, but would need to be higher to meet the additional requirement of training and competition. With the exception of vitamin A and iron, all micronutrient intakes were higher than the DRI. In conclusion, recommendations for female soccer players are to encourage consumption of carbohydrate-electrolyte beverages to enhance carbohydrate intake and increase fluid intake, and ensure sufficient iron rich foods are included in the diet to meet the DRI. Key points Female soccer players demonstrate a low energy intake in relation to predicted requirements, but were in energy balance in this study. Increased carbohydrate intake may be beneficial to both training and competition performance of elite female soccer players Fluid requirements should be addressed on an individual basis and matched to player requirements. The iron status of female soccer players may be compromised due to insufficient dietary intake to meet the DRV. PMID:24198690

Nutritional practices of national female soccer players: analysis and recommendations.

Science.gov (United States)

Martin, Louise; Lambeth, Anneliese; Scott, Dawn

2006-01-01

The aim of the study was to establish the nutritional practices and activity patterns of elite female soccer players. The nutritional intake of 16 female England Soccer players was self-reported over a seven-day period. Participants were provided with written and verbal guidelines for the completion of the diaries. Training details were also recorded, and used in combination with BMR predictions to calculate daily energy expenditure. Energy, macronutrient and micronutrient intakes were determined using DietMaster 4.0 software. Results suggest that energy intake was low (1904 ± 366.3 kcal) in relation to previous recommendations for soccer players. Energy expenditure (2153.5 ± 596.2 kcal) was not significantly different (p > 0.05) from intake, suggesting energy balance was achieved. Carbohydrate (53.8 ± 6.8%), protein (16.8 ± 2.1%) and fat (28.8 ± 6.6%) intakes were in line with recommendations. Fluid intake (2466 ± 1350.5ml·day(-1)) was sufficient to meet baseline recommendations, but would need to be higher to meet the additional requirement of training and competition. With the exception of vitamin A and iron, all micronutrient intakes were higher than the DRI. In conclusion, recommendations for female soccer players are to encourage consumption of carbohydrate-electrolyte beverages to enhance carbohydrate intake and increase fluid intake, and ensure sufficient iron rich foods are included in the diet to meet the DRI. Key pointsFemale soccer players demonstrate a low energy intake in relation to predicted requirements, but were in energy balance in this study.Increased carbohydrate intake may be beneficial to both training and competition performance of elite female soccer playersFluid requirements should be addressed on an individual basis and matched to player requirements.The iron status of female soccer players may be compromised due to insufficient dietary intake to meet the DRV.

In-season training periodization of professional soccer players

Directory of Open Access Journals (Sweden)

A Los Arcos

2017-04-01

Full Text Available The aim of this study was to quantify the seasonal perceived respiratory and muscular training loads (i.e., sRPEres-TL and sRPEmus-TL completed by elite-oriented young professional soccer players. Twentyfour players (20.3 ± 2.0 years belonging to the same reserve team of a Spanish La Liga club participated in this study. Only the players that were available to train for a whole week with the team and also to play the weekly game were considered: Starters, players that participated in the match for at least 45 min and Non- Starters, players that did not participate or played less than 45 minutes in the match. The competitive period was analysed after the division into 5x6-8 week blocks and 35x1 week microcycles. Data were also analysed with respect to number of days before the immediate match. Weekly TL variation across the in-season blocks was trivial-small for both groups except between Block 2 and Block 3 (ES= moderate. Substantial TL differences (ES= small–very likely were found between training days, the TL pattern being a progressive increase up to MD-3 followed by a decrease until MD-1. Except for the match, sRPEres-/sRPEmus-TL was very similar between Starters and Non-Starters. In summary, perceived TL across the season displayed limited variation. Coaches periodized training contents to attain the highest weekly TL 72 hours before the match to progressively unload the players between MD-3 and the match day. The data revealed that the TL arising from the weekly game was solely responsible for the observed higher weekly TL of Starters in comparison with Non-Starters.

Research of individual psychological particular qualities handball players 15-17 years.

Directory of Open Access Journals (Sweden)

Bikova H.O.

2011-02-01

Full Text Available The differences of individual-psychological characteristics of young handball players playing in different game roles. It is shown the relationship of certain personality characteristics of athletes with a line of attack handball players. In research took part handball players at the age of 15-17 years. It is analyzed data from questionnaires by R. Kettela and R. Rusalova. Evaluated the differences in the properties of the temperament handball players of different roles. Established that the distribution of game functions athletes must take into account their individual psychological characteristics.

Modelling Virtual Camera Behaviour Through Player Gaze

DEFF Research Database (Denmark)

Picardi, Andrea; Burelli, Paolo; Yannakakis, Georgios N.

2012-01-01

industry and game AI research focus on the devel- opment of increasingly sophisticated systems to automate the control of the virtual camera integrating artificial intel- ligence algorithms within physical simulations. However, in both industry and academia little research has been carried out......In a three-dimensional virtual environment, aspects such as narrative and interaction largely depend on the placement and animation of the virtual camera. Therefore, virtual camera control plays a critical role in player experience and, thereby, in the overall quality of a computer game. Both game...... on the relationship between virtual camera, game-play and player behaviour. We run a game user experiment to shed some light on this relationship and identify relevant dif- ferences between camera behaviours through different game sessions, playing behaviours and player gaze patterns. Re- sults show that users can...

There is no game without a player

DEFF Research Database (Denmark)

Larsen, Lasse Juel

on the subject matter from the catalogue of game theory. All four suggestions exclude the player from the relationship. This paper introduces a phenomenological point of view and includes the player in order to understand the relationship between structure and dressing. It argues that players constitute a bridge......This paper is a search for meaning or to be more precise a study of how meaning is produced between ontology and fiction in computer games. It sets out to investigate the relationship between formal abstract game structures and game representation (dressing) by presenting four suggestions...... or the center which establishes, upholds and renegotiate the relationship between formal game structure and game dressing. It also argues that players’ interaction with both structure and dressing produce meaning and the production of meaning is the relationship between formal abstract game structures and game...

Analyzing three-player quantum games in an EPR type setup.

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James M Chappell

Full Text Available We use the formalism of Clifford Geometric Algebra (GA to develop an analysis of quantum versions of three-player non-cooperative games. The quantum games we explore are played in an Einstein-Podolsky-Rosen (EPR type setting. In this setting, the players' strategy sets remain identical to the ones in the mixed-strategy version of the classical game that is obtained as a proper subset of the corresponding quantum game. Using GA we investigate the outcome of a realization of the game by players sharing GHZ state, W state, and a mixture of GHZ and W states. As a specific example, we study the game of three-player Prisoners' Dilemma.

Definition and assessment of physical efficiency of students – basketball players

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Kuzminchuk Artem

2016-04-01

Full Text Available Purpose: assess the level of physical efficiency of students – basketball players by using the Harvard step test. Material & Methods: the analysis of scientific-methodical literature, educational testing, pedagogical experiment, methods of mathematical statistics. For determination and assessment physical efficiency of students – basketball players used the Harvard step test. In pedagogical testing for assessing special performance was attended by 14 students – basketball players (n=14 men's teams of the Medical Institute of Sumy State University. Results: the analysis of scientific and technical literature showed gaps in training basketball players, namely, to improve the physical performance. Especially these problems are when basketball training sessions combine with study in higher educational institutions. The load that caused a combination of mental and physical labor is enough to affect on the performance, develop resistance to fatigue. Still need to look for approaches that can help in conditions of single 3-4 workouts per week to maintain a high level of physical capacity of basketball players. Conclusions: analyzing the test results of basketball team players at Medical Institute of Sumy State University, we can say that the level of physical performance is satisfactory and functional status is mediocre. Players need more regular training which includes special exercises with high intensity close to competitive conditions

Free-sugar, total-sugar, fibre, and micronutrient intake within elite youth British soccer players: a nutritional transition from schoolboy to fulltime soccer player.

Science.gov (United States)

Naughton, Robert J; Drust, Barry; O'Boyle, Andy; Abayomi, Julie; Mahon, Elizabeth; Morton, James P; Davies, Ian G

2017-05-01

It is recommended that soccer players consume a high carbohydrate diet to augment performance. However, growing evidence suggests that there is a link between high free-sugar (FS) intake (>5% total energy intake; TEI) and metabolic diseases. Furthermore, foods that are often high in sugar, such as processed foods, are typically lacking in nutrient quality. We therefore analysed total-sugar, FS, dietary fibre, and micronutrient intake of players from an English Premier League academy under (U) 18 (n = 13), U15/16 (n = 25), and U13/14 (n = 21) using a 7-day food diary. Data were compared with current United Kingdom (UK) dietary reference value (DRV) for FS via a t test. The U13/14s (10% ± 18%) and U15/16s (11% ± 30%) both consumed higher amounts of FS in comparison with the UK DRV of 5% TEI (P elite youth soccer players. We report an apparent "nutritional transition" from schoolboy to fulltime soccer player, with U18s showing a significantly lower intake of sugar in comparison with younger squads, and a similar intake of FS to the UK DRVs. Practitioners should target improving player education around sugar and fibre consumption.

Understanding gaming floor influences on player behaviour

OpenAIRE

Griffiths, MD

2009-01-01

Efforts to entice and retain player activity within a casino gaming environment require bringing to bear a range of sensory and physical influences. The challenge is to accomplish the operators’ objectives while at the same time ensuring any potential negative effects on the player are minimised. How casinos keep this in balance is at the heart of how the gaming floor works, and assessing such matters is becoming a necessary part of social responsibility.

Brain damage in former association football players

International Nuclear Information System (INIS)

Sortland, O.; Tysvaer, A.T.

1989-01-01

Thirty-three former football players from the National Football Team of Norway were examined by cerebral computer tomography (CT). The CT studies, evaluated for brain atrophy, visually and by linear measurements compared two different normal materials. One third of the players were found to have central cerebral atrophy. It is concluded that the atrophy probably was caused by repeated small head injuries during the football play, mainly in connection with heading the ball. (orig.)

No association between static and dynamic postural control and ACL injury risk among female elite handball and football players: a prospective study of 838 players.

Science.gov (United States)

Steffen, Kathrin; Nilstad, Agnethe; Krosshaug, Tron; Pasanen, Kati; Killingmo, Aleksander; Bahr, Roald

2017-02-01

Research on balance measures as potential risk factors for ACL injury is limited. To assess whether postural control was associated with an increased risk for ACL injuries in female elite handball and football players. Premier league players were tested in the preseason and followed prospectively for ACL injury risk from 2007 through 2015. At baseline, we recorded player demographics, playing experience, ACL and ankle injury history. We measured centre of pressure velocity in single-leg stabilisation tests and reach distances in the Star Excursion Balance Test. To examine the stability of postural control measures over time, we examined their short-term and long-term reproducibility. We generated logistic regression models, 1 for each of the proposed risk factors. A total of 55 (6.6%) out of 838 players (age 21±4 years; height 170±6 cm; body mass 66±8 kg) sustained a non-contact ACL injury after baseline testing (1.8±1.8 years). When comparing normalised balance measures between injured and uninjured players in univariate analyses, none of the variables were statistically associated with ACL injury risk. Short-term and long-term reproducibility of the selected variables was poor. Players with a previous ACL injury had a 3-fold higher risk of sustaining a new ACL injury compared with previously uninjured players (OR 2.9, CI 1.4 to 5.7). None of postural control measures examined were associated with increased ACL injury risk among female elite handball and football players. Hence, as measured in the current investigation, the variables included cannot be used to predict ACL injury risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

ANTROPOMETRIC CHARACTERISTICS AND MOTOR SKILLS OF YOUNG MONTENEGRO BASKETBALL PLAYERS

Directory of Open Access Journals (Sweden)

Milovan Ljubojević

2012-09-01

Full Text Available Testing and measurement in basketball is basically supposed to help in the initial evaluation and interpretation of features and capabilities of players that are important for their activity. The main objective of testing is the possibility of obtaining information about the three general indicators in basketball practice, namely: the level of current results in certain ability, the pace of results improvement in the ability and stability of the results in tests of ability. For this purpose, testing and measurement of young basketball players, members of the Montenegro under-18 team, was carried out. The aim of this paper is to present the basic features and capabilities of young basketball players of Montenegro and their comparison with some other teams. Variables from anthropometry space were measured: body height, arm span, reach height, body mass. Motor skills were observed by variables: the last squat, thrust from a flat bench, rear thrust, lying-sitting for 30 seconds, sargent test, long jump, 20 yard test, kamikaze, špagat, sitting bow. Based on the processed results it can be concluded that the motor skills of our young players, tested in this study, are at the level of the young players of other representations. The results will be of great help to coaches who work with these players.

Self-appraisal of hockey players of high class of different playing position

Directory of Open Access Journals (Sweden)

Oleksiy Mikhnov

2014-12-01

Full Text Available Purpose: to expose the features of display of self-appraisal for the hockey players of high class of different playing position. Material and Methods: for the exposure of level of self-appraisal for hockey players, information of sportsmen of high class, taking part in the matches of the Kontinental hockey league (KHL in a season 2013–2014 was probed sixteen hockey players, having a sporting digit MS and MSWC, took part in researches. Methods were used: pedagogical supervision, pedagogical analysis and generalization of front-rank experience, psychological testing, analysis of data of the special scientific-methodical literature, expert questioning, an analysis of data is the Internet. Results: findings allowed to set that the players of line of attack (central and extreme forward have more high level of self-appraisal for certain, than players of defence and hockey goalkeepers. This tendency is looked over both on the separate constituents of self-appraisal and on the whole on all spectrums of the studied indexes. The got results of researches rotined that the hockey players of high class had or middle or high level of self-appraisal. Among testable hockey players, players were not exposed with the low level of self-appraisal. Conclusions: the exposed distinctions in the level of self-appraisal of hockey players of high class can be used for diagnostics of playing predisposition and choice of playing line of business in a command.

Knee Control and Jump-Landing Technique in Young Basketball and Floorball Players.

Science.gov (United States)

Leppänen, M; Pasanen, K; Kulmala, J-P; Kujala, U M; Krosshaug, T; Kannus, P; Perttunen, J; Vasankari, T; Parkkari, J

2016-04-01

Poor knee alignment is associated with increased loading of the joints, ligaments and tendons, and may increase the risk of injury. The study purpose was to compare differences in knee kinematics between basketball and floorball players during a vertical drop jump (VDJ) task. We wanted to investigate whether basketball players, whose sport includes frequent jump-landings, exhibited better knee control compared with floorball players, whose sport involves less jumping. Complete data was obtained from 173 basketball and 141 floorball players. Peak knee valgus and flexion angles during the VDJ were analyzed by 3D motion analysis.Larger knee valgus angles were observed among basketball players (- 3.2°, 95%CI -4.5 to - 2.0) compared with floorball players (- 0.9°, 95%CI -2.3 to 0.6) (P=0.022). Basketball players landed with a decreased peak knee flexion angle (83.1°, 95%CI 81.4 to 84.8) compared with floorball players (86.5°, 95%CI 84.6 to 88.4) (P=0.016). There were no significant differences in height, weight or BMI between basketball and floorball players. Female athletes exhibited significantly greater valgus angles than males. This study revealed that proper knee control during jump-landing does not seem to develop in young athletes simply by playing the sport, despite the fact that jump-landings occur frequently in practice and games. © Georg Thieme Verlag KG Stuttgart · New York.

DIFFERENCES IN TECHNICAL MOVEMENT PRECISION WITH BALL TO NEW AGES SOCCER PLAYERS

Directory of Open Access Journals (Sweden)

Sami Sermaxhaj

2015-05-01

Full Text Available The primary goal of this research is to compare the accuracy of the collision of the ball to players of both age groups U-17 and U-19. The research was conducted on a sample of 100 young soccer players Kosovo divided into two groups: the first group comprised of 50 young players U17 and second group comprised of 50 young soccer players U-19. To assess the precision of the attack on the ball all the players they have subjected technical demonstration testing in four tests: (T-JUGGL, T-PASI, T-KROS, T-SHOOT. Through T-test method are proven differences in favor of players U-19 to U-17 in all tests of precision technical movements with the ball, but statistically significant differences are shown in the collision test at the gateway (T-SHOOT and the test ball juggling (T-JUGGL . The results obtained show us that more experienced players U-19 have a better precision in demonstrating the technical movements with the ball, compared to U-17 players. Assuming that the training process is very important to voice learning, mastering demonstration, acquisition, and precise technical movements with the ball, because the precision peak levels is very significant.

A biomechanical investigation of right-forward lunging step among badminton players.

Science.gov (United States)

Mei, Qichang; Gu, Yaodong; Fu, Fengqin; Fernandez, Justin

2017-03-01

This study presents the kinematics and plantar pressure characteristics of eight elite national-level badminton athletes and eight recreational college-level badminton players while performing a right-forward lunge movement in a laboratory-simulated badminton court. The hypothesis was that recreational players would be significantly different from elite players in kinematics and plantar pressure measures. Vicon ® motion capture and Novel ® insole plantar pressure measurement were simultaneously taken to record the lower extremity kinematics and foot loading during stance. Recreational players showed significantly higher peak pressure in the lateral forefoot (P = 0.002) and force time integral in the lateral forefoot (P = 0.013) and other toes (P = 0.005). Elite athletes showed higher peak pressure in the medial forefoot (P = 0.003), hallux (P = 0.037) and force time integral in the medial forefoot (P = 0.009). The difference in landing techniques for the lunge step between elite athletes and recreational players was observed with peak ankle eversion (-38.2°±2.4° for athletes and -11.1°±3.9° for players, P = 0.015); smaller knee range of motion in the coronal and transverse planes, with differences in peak knee adduction (28.9°±6.8° for athletes and 15.7°±6.2° for players, P = 0.031); peak knee internal rotation (20.3°±1.3° for athletes and 11.8°±3.2° for players, P = 0.029) and peak hip flexion (77.3°±4.1° for athletes and 91.3°±9.3° for players, P = 0.037).

Patellar tendinopathy in junior basketball players: a controlled clinical and ultrasonographic study of 268 patellar tendons in players aged 14-18 years.

Science.gov (United States)

Cook, J L; Khan, K M; Kiss, Z S; Griffiths, L

2000-08-01

Anterior knee pain is a common presenting complaint amongst adolescent athletes. We hypothesised that patellar tendinopathy may occur at a younger age than is generally recognised. Thus, we studied the patellar tendons in 134 elite 14- to 18-year-old female (n=64) and male (n=70) basketball players and 29 control swimmers (17 female, 12 male) clinically and with ultrasonography. We found that of 268 tendons, 19 (7%) had current patellar tendinopathy on clinical grounds (11% in males, 2% in females). Twenty-six percent of the basketball players' patellar tendons contained an ultrasonographic hypoechoic region. Ultrasonographic abnormality was more prevalent in the oldest tertile of players (17-18 years) than the youngest tertile (14-15.9 years). Of tendons categorised clinically as 'Never patellar tendinopathy', 22% had an ultrasonographic hypoechoic region nevertheless. This study indicates that patellar tendinopathy can occur in 14- to 18-year-old basketball players. Ultrasonographic tendon abnormality is 3 times as common as clinical symptoms.

Nutritional Habits & Knowledge in the Division I Collegiate Football Player

OpenAIRE

Hale, Mallory

2013-01-01

Objectives: Athlete’s nutritional habits and knowledge can directly affect their performance. The purpose of this study is to investigate the nutritional habits and knowledge of the Division I collegiate football player. Methods: The participants of this study are male Division I college football players at Utah State University. The athletes included 45 players ranging from 18-26 and include freshman through seniors. Results: Over eighty six percent of the athletes were unaware that a ...

The Player Engagement Process

DEFF Research Database (Denmark)

Schoenau-Fog, Henrik

2011-01-01

, categories and triggers involved in this process. By applying grounded theory to the analysis of the responses, a process-oriented player engagement framework was developed and four main components consisting of objectives, activities, accomplishments and affects as well as the corresponding categories...

The Physiological Profile of Junior Soccer Players at SSBB Surabaya Bhakti

Science.gov (United States)

Nashirudin, M.; Kusnanik, N. W.

2018-01-01

Soccer players are required to have good physical fitness in order to achieve optimum accomplishment; physical fitness stands as the foundation of technical and tactical proficiency as well as the mental maturity during the matches. The purpose of this study was to identify the physiological profile of junior soccer players of SSB Surabaya Bhakti age 16-17. The research was conducted at 20 junior soccer players. This research was quantitative with descriptive analysis. Data were collected by testing of physiological (anaerobic power and capacity including explosive leg power, speed, agility; aerobic capacity: cardiovascular endurance). Data was analyzed using percentage. The result showed that the percentage of explosive leg power of junior soccer players were 30% (good category), speed was 85% (average category), right agility was 90% (average category), left agility was 75% (average category). On the other hand, the aerobic power and capacity of the junior soccer players in this study was 50% (average category). The conclusion of this research is that the physiological profile of junior soccer players at SSB Surabaya Bhakti age 16-17 was majority in average category.

Adaptivity to Age, Gender, and Gaming Platform Topology in Physical Multi-Player Games

DEFF Research Database (Denmark)

Lund, Henrik Hautop; Friðriksson, Rafn Vídalín; Björnsson, Davíð Þór

2012-01-01

In games where players are competing against each other, it can be of interest to ensure that all players are challenged according to their individual skills. In order to investigate such adaptivity to the individual player in physical multi-player games, we developed a game on modular interactive...... tiles which can be used in both single-player and multi-player mode. We implemented simple adaptivity methods and tested these with different user groups including children and adults of both genders. The results show statistically significant differences in the game interactions between children...... and adults, and between male and female players. Also, results show statistically significant differences in the game interactions between different physical set-ups of the modular interactive tiles, i.e. the interaction depended on the topology of the modular tiles set-up. Changing the physical set...

Laterality related to the successive selection of Dutch national youth soccer players.

Science.gov (United States)

Verbeek, Jan; Elferink-Gemser, Marije T; Jonker, Laura; Huijgen, Barbara C H; Visscher, Chris

2017-11-01

In the general population, estimates of left-foot preference are around 20%. In soccer, specific tasks create positional demands, requiring 40% of the players to be left-footed. Whether and how this is related to the selection of players is unknown. To examine the successive selection of soccer players for Dutch national youth teams in relation to foot preference, 280 youth players (age = 16.2 ± 1.08 years) were monitored from the U16 through the U19 teams over the last 5 years. No difference in successive selection between left- and right-footed players was found (p soccer teams.

Position-Specific Acceleration and Deceleration Profiles in Elite Youth and Senior Soccer Players.

Science.gov (United States)

Vigh-Larsen, Jeppe F; Dalgas, Ulrik; Andersen, Thomas B

2018-04-01

Vigh-Larsen, JF, Dalgas, U, and Andersen, TB. Position-specific acceleration and deceleration profiles in elite youth and senior soccer players. J Strength Cond Res 32(4): 1114-1122, 2018-The purpose of the study was to characterize and compare the position-specific activity profiles of young and senior elite soccer players with special emphasis put on accelerations and decelerations. Eight professional senior matches were tracked using the ZXY tracking system and analyzed for the number of accelerations and decelerations and running distances within different speed zones. Likewise, 4 U19 and 5 U17 matches were analyzed for comparison between youth and senior players. In senior players, the total distance (TD) was 10,776 ± 107 m with 668 ± 28 and 143 ± 10 m being high-intensity running (HIR) and sprinting, respectively. Number of accelerations and decelerations were 81 ± 2 and 84 ± 3, respectively, with central defenders performing the lowest and wide players the highest number. Declines were found between first and second halves for accelerations and decelerations (11 ± 3%), HIR (6 ± 4%), and TD (5 ± 1%), whereas sprinting distance did not differ. U19 players performed a higher number of accelerations, decelerations, and TD compared with senior players. In conclusion, differences in the number and distribution of accelerations and decelerations appeared between player positions, which is of importance when monitoring training and match loads and when prescribing specific training exercises. Furthermore, youth players performed as much high-intensity activities as senior players, indicating that this is not a discriminating physiological parameter between these players.

Development of repeated sprint ability in talented youth basketball players.

Science.gov (United States)

te Wierike, Sanne C M; de Jong, Mark C; Tromp, Eveline J Y; Vuijk, Pieter J; Lemmink, Koen A P M; Malina, Robert M; Elferink-Gemser, Marije T; Visscher, Chris

2014-04-01

Factors affecting repeated sprint ability (RSA) were evaluated in a mixed-longitudinal sample of 48 elite basketball players 14-19 years of age (16.1 ± 1.7 years). Players were observed on 6 occasions during the 2008-09 and 2009-10 seasons. Three following basketball-specific field tests were administered on each occasion: the shuttle sprint test for RSA, the vertical jump for lower body explosive strength (power), and the interval shuttle run test for interval endurance capacity. Height and weight were measured; body composition was estimated (percent fat, lean body mass). Multilevel modeling of RSA development curve was used with 32 players (16.0 ± 1.7 years) who had 2 or more observations. The 16 players (16.1 ± 1.8 years) measured on only 1 occasion were used as a control group to evaluate the appropriateness of the model. Age, lower body explosive strength, and interval endurance capacity significantly contributed to RSA (p ≤ 0.05). Repeated sprint ability improved with age from 14 to 17 years (p ≤ 0.05) and reached a plateau at 17-19 years. Predicted RSA did not significantly differ from measured RSA in the control group (p ≥ 0.05). The results suggest a potentially important role for the training of lower body explosive strength and interval endurance capacity in the development of RSA among youth basketball players. Age-specific reference values for RSA of youth players may assist basketball coaches in setting appropriate goals for individual players.

Australian Football League concussion guidelines: what do community players think?

Science.gov (United States)

White, Peta E; Donaldson, Alex; Sullivan, S John; Newton, Joshua

2016-01-01

Background Preventing concussion in sport is a global challenge. To assess community-level adult male Australian Football players’ views on following the Australian Football League's (AFL) concussion guidelines. Methods 3 focus groups, each comprising 6 players from 1 regional league, were conducted until saturation of issues raised. Discussions followed a semistructured script and were audio-recorded and transcribed verbatim. Thematic analysis was conducted by 2 coders independently. Results Identified advantages of the guidelines included highlighting the seriousness of concussion; changing the culture around playing with concussion and shifting return-to-play decision responsibility from players to others. Disadvantages included players being removed from play unnecessarily; removal of players’ rights to decide if they are fit to play and players changing their behaviours to avoid being removed from play. Identified facilitators to guideline use included local league enforcement; broad information dissemination and impartial medically trained staff to assess concussion. Identified barriers to guideline use included players’ desire to play at all costs; external pressure that encouraged players to return to play prematurely; and inconvenience and cost. Conclusions Players generally understand that the AFL concussion guidelines protect their long-term welfare. However, their desire to play at all costs and help their team win is a common barrier to reporting concussion and adhering to guidelines. Leagues should take a lead role by mandating and enforcing the use of the guidelines and educating coaches, game day medical providers and players. The return-to-play component of the guidelines is complex and needs further consideration in the context of community sport. PMID:28890801

Dynamic Difficulty Adaptation for Heterogeneously Skilled Player Groups in Multiplayer Collaborative Games

OpenAIRE

Greciano, Miguel Cristian

2016-01-01

This work focuses on the combination of two key concepts: Dynamic Difficulty Adjustment/Adaptation (video games adapting their difficulty according to the in-game performance of players, making themselves easier if the player performs poorly or more difficult if the player performs well) and Collaborative Multiplayer Games (video games where two or more human players work together to achieve a common goal). It considers and analyzes the challenges, potential and possibilities of Dynamic Diffi...

Player Collaboration in the Explorative Sound Environment ToneInk

DEFF Research Database (Denmark)

Hansen, Anne-Marie S.; Andersen, Hans Jørgen; Raudaskoski, Pirkko Liisa

2016-01-01

mutual awareness, and in general were more passive when they needed to monitor a screen interface that supported the sound environment. Player collaboration was strongest when players negotiated rhythm, while the negotiation of melody was temporally offset and consisted of long individual explorations....

Non-coding RNAs enter mitosis: functions, conservation and implications

Directory of Open Access Journals (Sweden)

Kai Toshie

2011-02-01

Full Text Available Abstract Nuage (or commonly known as chromatoid body in mammals is a conserved germline-specific organelle that has been linked to the Piwi-interacting RNA (piRNA pathway. piRNAs are a class of gonadal-specific RNAs that are ~23-29 nucleotides in length and protect genome stability by repressing the expression of deleterious retrotransposons. More recent studies in Drosophila have implicated the piRNA pathway in other functions including canalization of embryonic development, regulation of maternal gene expression and telomere protection. We have recently shown that Vasa (known as Mouse Vasa Homolog in mouse, a nuage component, plays a mitotic role in promoting chromosome condensation and segregation by facilitating robust chromosomal localization of condensin I in the Drosophila germline. Vasa functions together with Aubergine (a PIWI family protein and Spindle-E/mouse TDRD-9, two other nuage components that are involved in the piRNA pathway, therefore providing a link between the piRNA pathway and mitotic chromosome condensation. Here, we propose and discuss possible models for the role of Vasa and the piRNA pathway during mitosis. We also highlight relevant studies implicating mitotic roles for RNAs and/or nuage in other model systems and their implications for cancer development.

Cardiac dimensions and function in female handball players.

Science.gov (United States)

Malmgren, A; Dencker, M; Stagmo, M; Gudmundsson, P

2015-04-01

Long-term intensive endurance training leads to increased left ventricular mass and increased left ventricular end-diastolic and left atrial end-systolic diameters. Different types of sports tend to give rise to distinct morphological forms of the athlete's heart. However, the sport-specific aspects have not been fully investigated in female athletes. The purpose of the present study was to investigate differences in left and right cardiac dimensions, cardiac volumes, and systolic and diastolic function in elite female handball players compared to sedentary controls. A cross-sectional study of 33 elite female handball players was compared to 33 matched sedentary controls. Mean age was 21.5±2 years. The subjects underwent echocardiography examinations, both 2-dimensional (2DE) and 3-dimensional (3DE). Cardiac dimensions and volumes were quantified using M-mode, 2DE and 3DE. Systolic and diastolic left ventricular functions were also evaluated. All cardiac dimensions and volumes were adjusted for body surface area (BSA). Left atrium and left ventricle volumes were significantly (Phandball players compared with sedentary controls. Even right atrium area as well as right ventricular end-diastolic and end-systolic area were significantly (Phandball players. Significant differences were observed in three out of five systolic parameters. Most diastolic function parameters did not differ between the two groups. The findings from the present study suggest that similar cardiac remodeling takes place in elite female handball players as it does in athletes pursuing endurance or team game sports.

Psychopathology of Online Poker Players: Review of Literature.

Science.gov (United States)

Moreau, Axelle; Chabrol, Henri; Chauchard, Emeline

2016-06-01

Background and aims Online Texas Hold'em poker has become a spectacular form of entertainment in our society, and the number of people who use this form of gambling is increasing. It seems that online poker activity challenges existing theoretical concepts about problem gambling behaviors. The purpose of this literature review is to provide a current overview about the population of online poker players. Methods To be selected, articles had to focus on psychopathology in a sample of online poker players, be written in English or French, and be published before November 2015. A total of 17 relevant studies were identified. Results In this population, the proportion of problematic gamblers was higher than in other forms of gambling. Several factors predicting excessive gambling were identified such as stress, internal attribution, dissociation, boredom, negative emotions, irrational beliefs, anxiety, and impulsivity. The population of online poker players is largely heterogeneous, with experimental players forming a specific group. Finally, the validity of the tools used to measure excessive or problematic gambling and irrational beliefs are not suitable for assessing online poker activity. Discussion and conclusions Future studies need to confirm previous findings in the literature of online poker games. Given that skills are important in poker playing, skill development in the frames of excessive use of online poker should be explored more in depth, particularly regarding poker experience and loss chasing. Future research should focus on skills, self-regulation, and psychopathology of online poker players.

The Astro Learning Design Player

NARCIS (Netherlands)

Sharples, Paul; Wilson, Scott; Popat, Kris; Griffiths, David; Beauvoir, Phillip

2010-01-01

Sharples, Paul Wilson, S., Popat, K., Griffiths, D., Beauvoir, P. (2009) The Astro Learning Design Player. This software is distributed under the three clause BSD license, copyright TENCompetence Foundation

Kinanthropometric characteristics in teenager basketball players

Directory of Open Access Journals (Sweden)

Maria Abella del Campo

2015-12-01

Full Text Available Introduction: Basketball is a sport with a high heterogeneity anthropometric as playing position. Point guard is usually the lowest player but also the fastest. Guard is similar to point guard, faster and more agile than the others. Small forward has an intermediate height between the inside and outside players and it combines height with velocity. And center (pivot has a physical role, it has the highest and more muscle mass. The aim of this study is to describe the kinanthropometric profile of male cadet “Valencia Basket Club”. Material and Methods: A total of 20 male cadet basketball players were evaluated (15.35±0.59 years old. An anthropometrist level 1 took anthropometric measures according to the methodology of the International Society for the Advancement of Kinanthropometry (ISAK. Body composition was calculated according to the kinanthropometry consensus of the Kinanthropometry Spanish Group (GREC, somatotype with Heath-Carter’s method and adiposemuscular and cardiovascular risk index. Results: Differences in values of weight, height, skinfold and body composition from variables of sample and position were observed. Lower values were from point guard position and higher values were from center position. An increasing trend of these parameters was established in the following order: point guard, guard, small forward and center. Conclusions: The Valencia Basket Club cadet player overall somatotype is balance ectomorph. To know kinanthropometric profile may be beneficial to develop specific training and nutrition plans as well as to see evolution and characteristics for optimal performance

A COMPARATIVE STUDY OF PERSONALITY OF INTERNATIONAL VOLLEYBALL PLAYERS OF BRAZIL AND INDIA

Directory of Open Access Journals (Sweden)

Govind Kadam

2010-06-01

Full Text Available The main objective was to study the personality of the volleyball players of India. All the players of Indian team and the players of Brazil team, who came for FIVB Men Volleyball World Championship held at Pune in August 2009, were selected for the study. They were administered the Cattell’s 16 PF questionnaire. The results wereanalyzed with the help of ‘t’ test which showed that there are significant differences found between Indian volleyball players and Brazilian Volleyball players on seven factors but not on nine factors of 16 PF Questionnaire. Indian players scored high on factor ‘F’, factor ‘I’ and factor ‘M’ whereas Brazilian players have scored high on factor ‘B’, factor ‘G’, factor ‘H’ and factor ‘L’. Indian players scored low on Factor B which means that they tend to be slow to learn and grasp and they were dull as compared with Brazilian team, and gives concrete and literal interpretation. This dullness simply represents poor functioning.

Transcriptional landscape of ncRNA and Repeat elements in somatic cells

KAUST Repository

Ghosheh, Yanal

2016-12-01

The advancement of Nucleic acids (DNA and RNA) sequencing technology has enabled many projects targeted towards the identification of genome structure and transcriptome complexity of organisms. The first conclusions of the human and mouse projects have underscored two important, yet unexpected, findings. First, while almost the entire genome is transcribed, only 5% of it encodes for proteins. Thereby, most transcripts are noncoding RNA. This includes both short RNA (<200 nucleotides (nt)) comprising piRNAs; microRNAs (miRNAs); endogenous Short Interfering RNAs (siRNAs) among others, and includes lncRNA (>200nt). Second, a significant portion of the mammalian genome (45%) is composed of Repeat Elements (REs). RE are mostly relics of ancestral viruses that during evolution have invaded the host genome by producing thousands of copies. Their roles within their host genomes have yet to be fully explored considering that they sometimes produce lncRNA, and have been shown to influence expression at the transcriptional and post-transcriptional levels. Moreover, because some REs can still mobilize within host genomes, host genomes have evolved mechanisms, mainly epigenetic, to maintain REs under tight control. Recent reports indicate that REs activity is regulated in somatic cells, particularily in the brain, suggesting a physiological role of RE mobilization during normal development. In this thesis, I focus on the analysis of ncRNAs, specifically REs; piRNAs; lncRNAs in human and mouse post-mitotic somatic cells. The main aspects of this analysis are: Using sRNA-Seq, I show that piRNAs, a class of ncRNAs responsible for the silencing of Transposable elements (TEs) in testes, are present also in adult mouse brain. Furthermore, their regulation shows only a subset of testes piRNAs are expressed in the brain and may be controlled by known neurogenesis factors. To investigate the dynamics of the transcriptome during cellular differentiation, I examined deep RNA-Seq and Cap

Incidence and variance of foot and ankle injuries in elite college football players.

Science.gov (United States)

Kaplan, Lee D; Jost, Patrick W; Honkamp, Nicholas; Norwig, John; West, Robin; Bradley, James P

2011-01-01

We conducted a study on the risk for foot and ankle injuries in college football players on the basis of injury type and player position. In February 2006, we evaluated 320 intercollegiate football players at the National Football League Combine. All pathologic conditions and surgical procedures of the foot and ankle were recorded, and data were analyzed by player position to detect any trends. Seventy-two percent (n = 231) of the players had a history of foot and ankle injuries, with a total of 287 foot and ankle injuries (1.24 injuries/player injured). The most common injuries were lateral ankle sprain (n = 115), syndesmotic sprain (50), metatarsophalangeal dislocation/turf toe (36), and fibular fracture (25). Foot and ankle injuries were most common in kickers/punters (100% incidence), special teams (100%), running backs (83%), wide receivers (83%), and offensive linemen (80%). Lateral ankle sprains, the most common injuries, were treated surgically only 2.6% of the time. Offensive linemen were most likely to have had syndesmotic sprains (32%), and quarterbacks had the highest incidence of fibular fractures (16%). Foot and ankle injuries are common in collegiate football players, affecting 72% of players. Thirteen percent underwent surgical treatment. Trends are seen in the types of injuries for the different player positions.

Physical and physiological profiles of Boland netball players | Venter ...

African Journals Online (AJOL)

The netball players were assessed for flexibility, speed, agility, power and aerobic endurance. Anthropometrical measurements were also taken. Descriptive statistics were calculated, after which Student s unpaired t-tests were used to compare results between the Boland and Australian under-21 netball players. Results.

Attributes of top elite team-handball players.

Science.gov (United States)

Massuça, Luís M; Fragoso, Isabel; Teles, Júlia

2014-01-01

Researchers in the field of excellence in sport performance are becoming increasingly focused on the study of sport-specific characteristics and requirements. In accordance with this, the purposes of this study were (a) to examine the morphologic-, fitness-, handball-specific skills and psychological and "biosocial" differences between top elite and nontop elite team-handball players and (b) to investigate the extent to which they may be used to identify top elite team-handball players. One hundred sixty-seven adult male team-handball players were studied and divided in 2 groups: top elite (n = 41) and nontop elite (n = 126). Twenty-eight morphologic-, 9 fitness-, 1 handball-specific skills and 2 psychological-based and 2 "biosocial"-based attributes were used. Top elite and nontop elite groups were compared for each variable of interest using Student's t-test, and 5 logistic regression analyses were performed with the athlete's performance group (top elite or nontop elite) as the dependent variable and the variables of each category as predictors. The results showed that (a) body mass, waist girth, radiale-dactylion length, midstylion-dactylion length, and absolute muscle mass (morphologic model); (b) 30-m sprint time, countermovement jump height and average power, abdominal strength and the class of performance in the Yo-Yo Intermittent Endurance Test (fitness model); (c) offensive power (specific-skills model); (d) ego-based motivational orientation (psychological model); (e) socioeconomic status and the energy spent (for week) in handball activity (biosocial model); significantly (p handball player. Moreover, the fitness model exhibited higher percentages of correct classification (i.e., 91.5%) than all the other models did. This study provided (a) the rational to reduce the battery of tests for evaluation purposes, and (b) the initial step to work on building a multidisciplinary model to predict the probability of a handball athlete to be a top elite player.

Strength and Jump Biomechanics of Elite and Recreational Female Youth Soccer Players

Science.gov (United States)

Chrisman, Sara P.; O'Kane, John W.; Polissar, Nayak L.; Tencer, Allan F.; Mack, Christopher D.; Levy, Marni R.; Schiff, Melissa A.

2012-01-01

Context Most researchers investigating soccer injuries have studied elite athletes because they have greater athletic-exposure hours than other athletes, but most youth participate at the recreational level. If risk factors for injury vary by soccer level, then recommendations generated using research with elite youth soccer players might not generalize to recreational players. Objective To examine injury risk factors of strength and jump biomechanics by soccer level in female youth athletes and to determine whether research recommendations based on elite youth athletes could be generalized to recreational players. Design Cross-sectional study. Setting Seattle Youth Soccer Association. Patients or Other Participants Female soccer players (N = 92) aged 11 to 14 years were recruited from 4 randomly selected elite (n = 50; age = 12.5 years, 95% confidence interval [95% CI]) = 12.3, 12.8 years; height = 157.8 cm, 95% CI = 155.2, 160.3 cm; mass = 49.9 kg, 95% CI = 47.3, 52.6 kg) and 4 randomly selected recreational (n = 42; age = 13.2 years, 95% CI = 13.0, 13.5 years; height = 161.1 cm, 95% CI = 159.2, 163.1 cm; mass = 50.6 kg, 95% CI = 48.3, 53.0 kg) soccer teams. Main Outcome Measure(s) Players completed a questionnaire about demographics, history of previous injury, and soccer experience. Physical therapists used dynamometry to measure hip strength (abduction, adduction, extension, flexion) and knee strength (flexion, extension) and Sportsmetrics to measure vertical jump height and jump biomechanics. We compared all measurements by soccer level using linear regression to adjust for age and mass. Results Elite players were similar to recreational players in all measures of hip and knee strength, vertical jump height, and normalized knee separation (a valgus estimate generated using Sportsmetrics). Conclusions Female elite youth players and recreational players had similar lower extremity strength and jump biomechanics. This suggests that recommendations generated from

Teaching Beginning Trombone Players.

Science.gov (United States)

Fallis, Todd L.

2001-01-01

Discusses the process of introducing the trombone to beginning students and addresses the issue of warming-up. Provides resources for beginning trombone methods, band methods, and daily warm-up studies. Includes resources for scale studies and etudes for beginning to intermediate trombone players. (CMK)

Ultrasonographic investigation of the Achilles tendon in elite badminton players using color Doppler.

Science.gov (United States)

Boesen, Morten Ilum; Boesen, Anders; Koenig, Merete Juhl; Bliddal, Henning; Torp-Pedersen, Soren

2006-12-01

The most frequent injuries in badminton players are in the lower extremities, especially in the Achilles tendon. The game of badminton may be related to abnormal intratendinous flow in the Achilles tendon as detected by color Doppler ultrasound. To a certain extent, this blood flow might be physiological, especially when examined after match. Cohort study (prevalence); Level of evidence, 3. Seventy-two elite badminton players were interviewed regarding Achilles tendon pain (achillodynia) in the preceding 3 years. Color Doppler was used to examine the tendons of 64 players before their matches and 46 players after their matches. Intratendinous color Doppler flow was graded from 0 to 4. The Achilles tendon was divided into dominant (eg, right side for right-handed players and vice versa) and nondominant side and classified as midtendon, preinsertional, and calcaneal areas. Of 72 players, 26 had experienced achillodynia in 34 tendons, 18 on the dominant side and 16 on the nondominant side. In 62% of the players with achillodynia, the problems had begun slowly, and the median duration of symptoms was 4 months (range, 0-36 months). Thirty-five percent had ongoing pain in their tendons for a median duration of 12 months (range, 0-12 months). Achillodynia was not associated with the self-reported training load or with sex, age, weight, singles or doubles players, or racket side. Forty-six players were scanned before and after match. At baseline, color Doppler flow was present in the majority of players, and only 7 (16%) players had no color Doppler flow in either tendon. After match, all players had some color Doppler flow in 1 or both tendons. Achillodynia and color Doppler flow were related in the nondominant Achilles tendon (chi-square, P = .008). The grades of Doppler flow also increased significantly after match in the preinsertional area in both the nondominant (P = .0002) and dominant (P = .005) side tendons. A large proportion of the players had experienced

An Optimized Player Taxonomy Model for Mobile MMORPGs with Millions of Users

OpenAIRE

You, Fang; Liu, Jianping; Guan, Xinjian; Wang, Jianmin; Zheng, Zibin; Tam, Peter

2011-01-01

Massively multiplayer online role-playing games (MMORPGs) have great potential as sites for research within the social and human-computer interaction. In the MMORPGs, a stability player taxonomy model is very important for game design. It helps to balance different types of players and improve business strategy of the game. The players in mobile MMORPGs are also connected with social networks; many studies only use the player's own attributes statistics or questionnaire survey method to predi...

Heart rate and activity profile for young female soccer players

OpenAIRE

Barbero Álvarez, José Carlos; Gómez López, Maite; Barbero Álvarez, Verónica; Granda Vera, Juan; Castagna, Carlo

2008-01-01

The physical and physiological demands of high-level male soccer have been studied extensively, while few studies have investigated the demands placed on females during match-play, however, there is no information available about the heart rate and activity profile of young female soccer players during match play. Therefore, the aim of this study was to examine cardiovascular (heart-rates HR) and physical demands of young female soccer players during a match. Players were observed during a fr...

Laterality of the legs in young female soccer players

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Antosiak-Cyrak Katarzyna Z.

2015-12-01

Full Text Available Purpose. The aim of the present study was assessment of laterality of the legs of young female soccer players and their non-training counterparts. Methods. The study sample comprised 9 female soccer players and 19 non-training girls. They underwent three measurement sessions, one every six months. The applied tests included kinesthetic differentiation, rate of local movements, static balance, single-leg hop, rate of global movements, strength and speed, and functional asymmetry of the legs tests. Results. The soccer players were better than the controls in their performance of the rate of local movements, rate of global movements, kinesthetic differentiation, single-leg 15m timed hop and static balance tests. Smaller differences between the results of the left and the right legs in soccer players, than in non-training girls, were noted in the rate of local movements, rate of global movements and kinesthetic differentiation tests. In the static balance test, the differences were greater in the group of soccer players. Conclusions. Lateralization of the lower limbs is a highly complex characteristic with a different variability in athletes than in nontraining individuals. The results of the present study also point to the specialization of soccer players’ left legs in body balance and single-leg hop tests.

Relative age effect and selection of young basketball players

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Vučković Igor

2013-01-01

Full Text Available Purpose of the present study was to examine whether influence of relative age effect (RAE exists or not in the selected 13 year old basketball players. Subjects were 20 basketball players (HT=177.35cm±6.73, BW=61.42kg±8.98, average age 13 years and 7 months ±.28, average experience in basketball training 4 years and 6 months ±1.15. Sample was divided in two groups: 11 players born in first half of the year and 9 players born in the second half of the year. One-way ANOVA was used in order to analyze the differences between the two groups of players in set of anthropometric variables (body height, arm span, standing reach height, body weight and percentage of body fat, motor variables (velocity of neuromuscular reaction time, vertical jump, 5 meters sprint, 10 meters sprint, 20 meters sprint, T-test, Zig-zag test, ball throw from sitting position, Sit-ups for 30 seconds and standing forward bend and one functional variable (20-M shuttle run test. Subjects do not differ in applied set of parameters, except in on variable (sit-ups for 30 seconds, p=.040. It was concluded that RAE does not exist in this sample of examinees.

A comparison of two conative characteristics of top basketball and recreational table tennis players.

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Sindik, Josko; Missoni, Sasa

2013-05-01

The purpose of this study is to adapt imported instruments for measuring multidimensional perfectionism in sport situations and perceived group cohesion, in terms of construct validity and reliability, as well as from the aspect of interpretability, addressed on Croatian samples of athletes. Group Environment Questionnaire (GEQ) and Sport Multidimensional Perfectionism Scale (MSSP) are applied. The sample of 223 male Croatian athletes comprises of N1 = 107 top basketball players from nine teams in A-1 Croatian Basketball League and N2 = 116 recreational table tennis players who play in Table Tennis Organization of Clubs and Actives in Zagreb. Principal Components Analyses at both instruments showed two-component structures: combined social-task cohesion and friendship were latent dimensions of perceived group cohesion, while the internalized standards and externalized standards revealed two aspects of multidimensional perfectionism in sport situations. In perceived group cohesion, basketball players achieved higher average results than table tennis players in the friendship, while the table tennis players showed higher combined social and task orientation than basketball players. In multidimensional sport perfectionism, basketball players have higher average result than table tennis players in the dimension of internalized perfectionism, but in externalized perfectionism there is no statistical significant difference. Younger players showed higher average results than older players in the dimension of friendship, while older players showed higher combined social and task orientation than younger players. Younger players have higher average scores in internalized perfectionism. The main importance of the research is adjustment of multidimensional perfectionism in sport situations and perceived group cohesion to Croatian athletes, providing additional possibility of cross-cultural adjustment of both concepts, psychometrically and theoretically.

Comparison of posture among adolescent male volleyball players and non-athletes

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Małgorzata Grabara

2014-11-01

Full Text Available Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified.

Comparison of posture among adolescent male volleyball players and non-athlete

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Małgorzata Grabara

2014-10-01

Full Text Available Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified.

Comparison of posture among adolescent male volleyball players and non-athletes

Science.gov (United States)

2014-01-01

Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified. PMID:25729154

An Analysis of Futsal Players' Self-Esteem Levels

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Kocak, Mehmet

2015-01-01

The purpose of this study is to investigate the self-esteem levels of futsal players according to certain variables. The samples of the study constituted 119 females and 96 males; a total of 215 players with an average age of 21.57 ± 2.20 years. The research was carried out with the end of "Rosenberg self-esteem Scale" developed by…

Utilization of cues in action anticipation in table tennis players.

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Zhao, Qi; Lu, Yingzhi; Jaquess, Kyle J; Zhou, Chenglin

2018-04-11

By manipulating the congruency between body kinematics and subsequent ball trajectory, this study investigated the anticipation capabilities of regional-level, college-level, and novice table tennis players using a full video simulation occluder paradigm. Participants watched footage containing congruent, incongruent, or no ball trajectory information, to predict the landing point of the ball. They were required to choose between two potential locations to make their prediction. Percent accuracy and relevant indexes (d-prime, criterion, effect size) were calculated for each condition. Results indicated that experienced table tennis players (both regional and college players) were superior to novices in the ability to anticipate ball trajectory using kinematic information, but no difference was found between regional-level and college-level players. The findings of this study further demonstrate the superior anticipation ability of experienced table tennis players. Furthermore, the present result suggests that there may be a certain "baseline" level of motor experience in racquet sports for effective action anticipation, while the addition of further motor experience does not appear to assist direction anticipation.

Doubly Disadvantaged? The Relative Age Effect in Poland's Basketball Players.

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Rubajczyk, Krystian; Świerzko, Kamil; Rokita, Andrzej

2017-06-01

The aim of this study was to identify the relative age effect (RAE) in young Polish male (n = 3849) and female (n = 3419) basketball players aged 14 to 22 years competing in the elite games of the Polish Youth Championships. The distribution of birth dates, body height, players' match statistics, and the results of teams participating in championships were identified. The RAE was observed in male and female group, regardless of players age. Nevertheless, the greatest disproportion in the distribution of dates of birth was found in U16 group of boys (V = 0.25, p born in the first half of a calendar year. The research results show the impact of the RAE on the success of youth basketball teams in Poland. The month of birth, body height and sex may determine sporting achievements in youth basketball. Coaches should consider the chronological age and pubertal growth acceleration (APHV-age at peak height velocity) of players to optimize the process of identifying gifted basketball players, especially among boys of 14 years of age.

Modeling attacking of high skills volleyball players

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Vladimir Gamaliy

2014-12-01

Full Text Available Purpose: to determine the model indicators of technical and tactical actions in the attack highly skilled volleyball players. Material and Methods: the study used statistical data of major international competitions: Olympic Games – 2012 World Championships – 2010, World League – 2010–2014 European Championship – 2010–2014. A total of 130 analyzed games. Methods were used: analysis and generalization of scientific and methodological literature, analysis of competitive activity highly skilled volleyball players, teacher observation, modeling technical and tactical actions in attacking highly skilled volleyball players. Results: it was found that the largest volume application of technical and tactical actions in the attack belongs to the group tactics «supple movement», whose indicator is 21,3%. The smallest amount of application belongs to the group tactics «flight level» model whose indicators is 5,4%, the efficiency of 3,4%, respectively. It is found that the power service in the jump from model parameters used in 51,6% of cases, the planning targets – 21,7% and 4,4% planning to reduce. Attacks performed with the back line, on model parameters used in the amount of 20,8% efficiency –13,7%. Conclusions: we prove that the performance of technical and tactical actions in the attack can be used as model in the control system of training and competitive process highly skilled volleyball players

Heart Rate Variability Discriminates Competitive Levels in Professional Soccer Players.

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Proietti, Riccardo; di Fronso, Selenia; Pereira, Lucas A; Bortoli, Laura; Robazza, Claudio; Nakamura, Fabio Y; Bertollo, Maurizio

2017-06-01

Heart rate variability (HRV) has been increasingly used to monitor team sports athletes. Besides the traditional time domain indices (i.e., the SD of successive RR intervals [SDNN] and the root mean square difference of successive normal RR intervals [RMSSD]), recently the use of the stress score (SS), which is an inverse function of the SD2 index derived from the Poincaré plot, and the sympathetic/parasympathetic ratio (S/PS) to monitor soccer players has been proposed. However, the reliability of these new indices and the ability of HRV to differentiate between soccer competitive levels are unknown. The aim of this study was to analyze the reliability of the different HRV-derived indices in professional soccer players during the competitive period and to compare HRV of professional soccer players from 3 teams of distinct competitive levels (i.e., Italian Second Division [2D], European League [EL], and Champions League [CL]). Fifty-four male professional soccer players from 3 different teams of 2 European countries (Italy and Germany) participated in the study. The intraclass correlation coefficient values of the HRV indices varied from 0.78 (very large) to 0.90 (near perfect). The coefficient of variation (CV) values for RMSSD and SDNN were all soccer players and is able to differentiate between international- and national-level players.

Role-player expectations regarding the education of nursing research

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SCD Zeelie

2003-09-01

Full Text Available This article reports on role player expectations regarding the education of nursing research. The importance of the role player expectations are two-fold: firstly as a factor in the external environment influencing and guiding the formulation phase of the development of standards and secondly, due to the clear indications of problems regarding nursing research in the nursing profession in literature. The role player expectations were elicited using a qualitative, exploratory and contextual design. The role player population included nurse educators, nurses in managerial, clinical and research positions, students and the medical profession. The data was gathered using the naïve sketches and qualitative data analysis was done using Morse & Field’s approach (1996:103-107 in combination with Tesch’s data analysis approach as cited by Creswell (1994:154-156. Sixty initial categories were narrowed down to six final categories, which are the research learning programme, personnel, students, departmental policies, funding and support systems.

Clinicopathological Evaluation of Chronic Traumatic Encephalopathy in Players of American Football.

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Mez, Jesse; Daneshvar, Daniel H; Kiernan, Patrick T; Abdolmohammadi, Bobak; Alvarez, Victor E; Huber, Bertrand R; Alosco, Michael L; Solomon, Todd M; Nowinski, Christopher J; McHale, Lisa; Cormier, Kerry A; Kubilus, Caroline A; Martin, Brett M; Murphy, Lauren; Baugh, Christine M; Montenigro, Phillip H; Chaisson, Christine E; Tripodis, Yorghos; Kowall, Neil W; Weuve, Jennifer; McClean, Michael D; Cantu, Robert C; Goldstein, Lee E; Katz, Douglas I; Stern, Robert A; Stein, Thor D; McKee, Ann C

2017-07-25

Players of American football may be at increased risk of long-term neurological conditions, particularly chronic traumatic encephalopathy (CTE). To determine the neuropathological and clinical features of deceased football players with CTE. Case series of 202 football players whose brains were donated for research. Neuropathological evaluations and retrospective telephone clinical assessments (including head trauma history) with informants were performed blinded. Online questionnaires ascertained athletic and military history. Participation in American football at any level of play. Neuropathological diagnoses of neurodegenerative diseases, including CTE, based on defined diagnostic criteria; CTE neuropathological severity (stages I to IV or dichotomized into mild [stages I and II] and severe [stages III and IV]); informant-reported athletic history and, for players who died in 2014 or later, clinical presentation, including behavior, mood, and cognitive symptoms and dementia. Among 202 deceased former football players (median age at death, 66 years [interquartile range, 47-76 years]), CTE was neuropathologically diagnosed in 177 players (87%; median age at death, 67 years [interquartile range, 52-77 years]; mean years of football participation, 15.1 [SD, 5.2]), including 0 of 2 pre-high school, 3 of 14 high school (21%), 48 of 53 college (91%), 9 of 14 semiprofessional (64%), 7 of 8 Canadian Football League (88%), and 110 of 111 National Football League (99%) players. Neuropathological severity of CTE was distributed across the highest level of play, with all 3 former high school players having mild pathology and the majority of former college (27 [56%]), semiprofessional (5 [56%]), and professional (101 [86%]) players having severe pathology. Among 27 participants with mild CTE pathology, 26 (96%) had behavioral or mood symptoms or both, 23 (85%) had cognitive symptoms, and 9 (33%) had signs of dementia. Among 84 participants with severe CTE pathology, 75 (89

Tactical proficiency among table tennis players with and without intellectual disabilities.

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Van Biesen, Debbie; Mactavish, Jennifer; Vanlandewijck, Yves

2014-01-01

The effect of intellectual impairment on sports performance has received limited attention by researchers. As a contribution to closing this gap, the purpose of the present investigation was to examine the differences in tactical proficiency between table tennis players with and without intellectual disabilities (ID). These groups were matched for training-volume and experience and consisted of 41 male (age = 27±8) and 30 female (age= 28±8) elite players with ID and a reference group of 12 male (age= 24±12) and 5 female (age= 20±9) players without ID. In two different test settings - one a World Championship and the other a training camp - the players in each group performed 60 semi-standardised rallies against the same opponent. Players were told that 12 sets of five identical services would be delivered, and their goal was to return the service with the intention of 'winning the point'. The test results were validated for this study, to compute tactical proficiency scores (maximal score of eight points) for each player. A two-way Analysis of Variance (ANOVA) revealed significantly lower proficiency scores for players with ID than for those without ID. Repeated-measures ANOVA revealed that within each series of five rallies, starting with identical services, all participants were able to significantly improve their tactical proficiency gradually, but players without ID scored 4.3±0.5 from the first ball on, and while athletes with ID only 3.3±0.7 after five balls. The results of this study indicate that ID is associated with decreased tactical proficiency in table tennis.

Analysis of the Motor Activities of Professional Polish Soccer Players

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Andrzejewski Marcin

2016-12-01

Full Text Available Introduction. The aims of the present study were to determine the activity profiles of a large sample of Polish Premier League soccer players during elite-standard soccer matches depending on their position on the pitch and the intensity range of physical activity. Material and methods. The study sample comprised 1,178 players in 5 outfield positions: external defenders (ED, n = 289, central defenders (CD, n = 307, central midfield players (CM, n = 327, external midfield players (EM, n = 152, and forwards (F, n = 103. Altogether, 81 Polish League games held during four domestic seasons (2010-2011, 2011-2012, 2012-2013, and 2013-2014 were used in the analysis. A semi-automatic computerised player tracking system (Amisco Pro®, version 1.0.2, Nice, France was applied to create the match activity profiles of the teams. Results. The results of statistical analysis revealed that the average total distance covered by all the players (n = 1,178 was 11,313 ± 852 m. With respect to the players’ position on the pitch, the central midfielders travelled the longest average distance (11,894 ± 765 m during the game. The longest distance was covered in the V1 intensity range (62%, followed by V2 (15%, V3 (10%, V4 (8%, V5 (3%, and V6 (2%. Conclusions. The objective of this study was to verify the differences among playing positions and to quantify the demands placed on elite Polish soccer players in each individual position during match play. While analysing elite-level match play in terms of the overall distance covered in different categories of intensity, we found a number of statistically significant differences between different playing positions. The data presented in this study can be regarded as norms for elite soccer players, serve for present and future comparison, and represent the scientific basis for developing position-specific conditioning/training protocols in soccer.

Consequences of repeated blood-brain barrier disruption in football players.

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Nicola Marchi

Full Text Available The acknowledgement of risks for traumatic brain injury in American football players has prompted studies for sideline concussion diagnosis and testing for neurological deficits. While concussions are recognized etiological factors for a spectrum of neurological sequelae, the consequences of sub-concussive events are unclear. We tested the hypothesis that blood-brain barrier disruption (BBBD and the accompanying surge of the astrocytic protein S100B in blood may cause an immune response associated with production of auto-antibodies. We also wished to determine whether these events result in disrupted white matter on diffusion tensor imaging (DT scans. Players from three college football teams were enrolled (total of 67 volunteers. None of the players experienced a concussion. Blood samples were collected before and after games (n = 57; the number of head hits in all players was monitored by movie review and post-game interviews. S100B serum levels and auto-antibodies against S100B were measured and correlated by direct and reverse immunoassays (n = 15 players; 5 games. A subset of players underwent DTI scans pre- and post-season and after a 6-month interval (n = 10. Cognitive and functional assessments were also performed. After a game, transient BBB damage measured by serum S100B was detected only in players experiencing the greatest number of sub-concussive head hits. Elevated levels of auto-antibodies against S100B were elevated only after repeated sub-concussive events characterized by BBBD. Serum levels of S100B auto-antibodies also predicted persistence of MRI-DTI abnormalities which in turn correlated with cognitive changes. Even in the absence of concussion, football players may experience repeated BBBD and serum surges of the potential auto-antigen S100B. The correlation of serum S100B, auto-antibodies and DTI changes support a link between repeated BBBD and future risk for cognitive changes.

Consequences of Repeated Blood-Brain Barrier Disruption in Football Players

Science.gov (United States)

Puvenna, Vikram; Janigro, Mattia; Ghosh, Chaitali; Zhong, Jianhui; Zhu, Tong; Blackman, Eric; Stewart, Desiree; Ellis, Jasmina; Butler, Robert; Janigro, Damir

2013-01-01

The acknowledgement of risks for traumatic brain injury in American football players has prompted studies for sideline concussion diagnosis and testing for neurological deficits. While concussions are recognized etiological factors for a spectrum of neurological sequelae, the consequences of sub-concussive events are unclear. We tested the hypothesis that blood-brain barrier disruption (BBBD) and the accompanying surge of the astrocytic protein S100B in blood may cause an immune response associated with production of auto-antibodies. We also wished to determine whether these events result in disrupted white matter on diffusion tensor imaging (DT) scans. Players from three college football teams were enrolled (total of 67 volunteers). None of the players experienced a concussion. Blood samples were collected before and after games (n = 57); the number of head hits in all players was monitored by movie review and post-game interviews. S100B serum levels and auto-antibodies against S100B were measured and correlated by direct and reverse immunoassays (n = 15 players; 5 games). A subset of players underwent DTI scans pre- and post-season and after a 6-month interval (n = 10). Cognitive and functional assessments were also performed. After a game, transient BBB damage measured by serum S100B was detected only in players experiencing the greatest number of sub-concussive head hits. Elevated levels of auto-antibodies against S100B were elevated only after repeated sub-concussive events characterized by BBBD. Serum levels of S100B auto-antibodies also predicted persistence of MRI-DTI abnormalities which in turn correlated with cognitive changes. Even in the absence of concussion, football players may experience repeated BBBD and serum surges of the potential auto-antigen S100B. The correlation of serum S100B, auto-antibodies and DTI changes support a link between repeated BBBD and future risk for cognitive changes. PMID:23483891

37 CFR 254.2 - Definition of coin-operated phonorecord player.

Science.gov (United States)

2010-07-01

...-OPERATED PHONORECORD PLAYERS § 254.2 Definition of coin-operated phonorecord player. As used in this part..., currency, tokens, or other monetary units or their equivalent; (b) Is located in an establishment making no...

Lifetime prevalence of injuries in incoming division I collegiate football players.

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Sarac, Nikolas; Haynes, William; Pedroza, Angela; Kaeding, Christopher; Borchers, James

2017-11-01

The purpose of this study is to determine the lifetime prevalence of past injuries in incoming first year football players in a Division 1 college football team. Pre-participation questionnaires from 605 first-year football players over 20 years (1996-2015) were examined to determine the prevalence of concussions, stingers, fractures, and musculoskeletal surgeries sustained before playing at the collegiate level. Players were grouped by position: wide receiver and defensive back (WR/DB), offensive and defensive linemen (OL/DL), all other positions (OP), and unknown (UKN). Prevalence of injuries by year and position was compared using Pearson's χ 2 Test (p football injuries are on the rise. Under reporting is a significant concern as players may fear disqualification or that they are evaluated by the coaching staff based on their medical history. More research is needed to confirm lifetime injury prevalence and evaluate differences over time among football players.

Optimal development of rugby players: a case study | Rainsford ...

African Journals Online (AJOL)

An empirical study was conducted among 40 contracted Vodacom players from the Golden Lions Rugby Union who completed structured questionnaires prior to a physical testing. The majority of players were between 19 and 31 years. Ninety percent belonged to the white population group and 10% identified themselves ...

The Relative Age Effect and Physical Fitness Characteristics in German Male Tennis Players

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Alexander Ulbricht, Jaime Fernandez-Fernandez, Alberto Mendez-Villanueva, Alexander Ferrauti

2015-09-01

Full Text Available The aims of the study were to test: 1 whether the relative age effect (RAE was prevalent in young (U12-U18 German male tennis players; 2 the potential influence of age and/or skill level on RAE and 3 whether maturity, anthropometric and fitness measures vary according to birth date distribution in elite youth tennis players. For the present study the following male populations were analysed: Overall German population (n = 3.216.811, all players affiliated to the German Tennis Federation (DTB (n = 120.851, players with DTB official ranking (n = 7165, regional (n = 381 and national (n = 57 squads (11-17 years old, as well as the top 50 German senior players were analyzed. RAEs were more prevalent at higher competitive levels with more players born in the first quarter of the year compared with the reference population for ranked (29.6%, regional (38.1% and national (42.1% players. No systematic differences were found in any of the maturity, anthropometric and fitness characteristics of the regional squad players born across different quarters. RAEs are present in the DTB competitive system and it was more pronounced at higher competitive levels. Compared with early born, late born players who were selected into elite squads did not differ in maturation, anthropometric and fitness characteristics.

Prevalence, knowledge and attitude of prohibited substances use (doping) among Saudi sport players.

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