693 research outputs found

    UČINAK SELEKCIJE SNIŽENJA STABLJIKE NA UROD I KOMPONENTE URODA ZRNA JEČMA

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    This investigation deals with the effects of selection for short stem in population lines of the F4 generation derived from the barley cross between Timura x Osk. 4.208´2-84 developed by the single seed descent and pedigree method. Direct genetic gain from reducing the stem length was found to be 10.22 % at dense planting (400 kernels/m2) and 11.47 % at wide-spaced planting (100 kernels/m2). It was found that stem length had relatively high heritability (0.643 and 0.735). Large negative effects of reducing the stem length at wide-spaced and dense planting were estimated for the grain yield per plant, grain yield per plot and number of fertile tillers. Less pronounced negative effects were found for the grain weight per spike and grain number per spike. Phenotypic and genotypic correlations between stem length and other traits were mostly significant and positive with higher values at dense planting. Selection for a short stem length was efficient for the improvement of this trait. However, unfavorable correlations have significantly affected undesired expression of other traits, especially grain yield per plant, grain yield per plot and number of fertile tillers. Any further decrease of plant height should be accompanied by the appropriate selection for other traits, especially grain yield per plant, mass of one grain and harvest index.U radu su istraženi učinci selekcije na kraću stabljiku kod ječma u populaciji linija F4 generacije izvedene iz kombinacije križanja Timura x Osk.4.208´2-84 pomoću metode potomstva sjemenke po biljci (SSD) i pedigree metode. Ostvarena izravna genetska dobit sniženja stabljike bila je 10,22 % u gustoj sjetvi (400 zrna/m2 ) i 11,47 % u rijetkoj sjetvi (100 zrna/m2 ). Utvrđeno je da je dužina stabljike svojstvo relativno visokog heritabiliteta (0,643 i 0,735). Jaki negativni učinci sniženja dužine stabljike u rijetkoj i gustoj sjetvi procijenjeni su za urod zrna po biljci, urod zrna po parceli i broj plodnih vlati. Manje naglašeni negativni učinci utvrđeni su za masu zrna po klasu i broj zrna po klasu. Fenotipske i genotipske korelacije između dužine stabljike i drugih svojstava bile su uglavnom značajne i pozitivne s višim vrijednostima u gustoj sjetvi. Selekcija na skraćenje stabljike bila je učinkovita za poboljšanje toga svojstva. Međutim, nepovoljne korelacije značajno su utjecale na neželjenu ekspresiju drugih svojstava, naročito na urod zrna po biljci, urod zrna po parceli i broj plodnih vlati. Daljnje snižavanje visine stabljike trebalo bi biti praćeno i odgovarajućom selekcijom na druga svojstva, posebno urod zrna po biljci, masu zrna i žetveni indeks

    A Survey on Approximation Mechanism Design without Money for Facility Games

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    In a facility game one or more facilities are placed in a metric space to serve a set of selfish agents whose addresses are their private information. In a classical facility game, each agent wants to be as close to a facility as possible, and the cost of an agent can be defined as the distance between her location and the closest facility. In an obnoxious facility game, each agent wants to be far away from all facilities, and her utility is the distance from her location to the facility set. The objective of each agent is to minimize her cost or maximize her utility. An agent may lie if, by doing so, more benefit can be obtained. We are interested in social choice mechanisms that do not utilize payments. The game designer aims at a mechanism that is strategy-proof, in the sense that any agent cannot benefit by misreporting her address, or, even better, group strategy-proof, in the sense that any coalition of agents cannot all benefit by lying. Meanwhile, it is desirable to have the mechanism to be approximately optimal with respect to a chosen objective function. Several models for such approximation mechanism design without money for facility games have been proposed. In this paper we briefly review these models and related results for both deterministic and randomized mechanisms, and meanwhile we present a general framework for approximation mechanism design without money for facility games

    A preliminary audit of medical and aid provision in English Rugby union clubs:compliance with Regulation 9

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    BackgroundGoverning bodies are largely responsible for the monitoring and management of risks associated with a safe playing environment, yet adherence to regulations is currently unknown. The aim of this study was to investigate and evaluate the current status of medical personnel, facilities, and equipment in Rugby Union clubs at regional level in England.MethodsA nationwide cross-sectional survey of 242 registered clubs was undertaken, where clubs were surveyed online on their current medical personnel, facilities, and equipment provision, according to regulation 9 of the Rugby Football Union (RFU).ResultsOverall, 91 (45. 04%) surveys were returned from the successfully contacted recipients. Of the completed responses, only 23.61% (n = 17) were found to be compliant with regulations. Furthermore, 30.56% (n = 22) of clubs were unsure if their medical personnel had required qualifications; thus, compliance could not be determined. There was a significant correlation (p = −0.029, r = 0.295) between club level and numbers of practitioners. There was no significant correlation indicated between the number of practitioners/number of teams and number of practitioners/number of players. There were significant correlations found between club level and equipment score (p = 0.003, r = −0.410), club level and automated external defibrillator (AED) access (p = 0.002, r = −0.352) and practitioner level and AED access (p = 0.0001, r = 0.404). Follow-up, thematic analysis highlighted widespread club concern around funding/cost, awareness, availability of practitioners and AED training.ConclusionThe proportion of clubs not adhering overall compliance with Regulation 9 of the RFU is concerning for player welfare, and an overhaul, nationally, is required

    Cardiac Screening of Young Athletes: a Practical Approach to Sudden Cardiac Death Prevention.

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    PURPOSE OF REVIEW: We aim to report on the current status of cardiovascular screening of athletes worldwide and review the up-to-date evidence for its efficacy in reducing sudden cardiac death in young athletes. RECENT FINDINGS: A large proportion of sudden cardiac death in young individuals and athletes occurs during rest with sudden arrhythmic death syndrome being recognised as the leading cause. The international recommendations for ECG interpretation have reduced the false-positive ECG rate to 3% and reduced the cost of screening by 25% without compromising the sensitivity to identify serious disease. There are some quality control issues that have been recently identified including the necessity for further training to guide physicians involved in screening young athletes. Improvements in our understanding of young sudden cardiac death and ECG interpretation guideline modification to further differentiate physiological ECG patterns from those that may represent underlying disease have significantly improved the efficacy of screening to levels that may make screening more attractive and feasible to sporting organisations as a complementary strategy to increased availability of automated external defibrillators to reduce the overall burden of young sudden cardiac death

    Abnormal ECG Findings in Athletes: Clinical Evaluation and Considerations.

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    PURPOSE OF REVIEW: Pre-participation cardiovascular evaluation with electrocardiography is normal practice for most sporting bodies. Awareness about sudden cardiac death in athletes and recognizing how screening can help identify vulnerable athletes have empowered different sporting disciplines to invest in the wellbeing of their athletes. RECENT FINDINGS: Discerning physiological electrical alterations due to athletic training from those representing cardiac pathology may be challenging. The mode of investigation of affected athletes is dependent on the electrical anomaly and the disease(s) in question. This review will highlight specific pathological ECG patterns that warrant assessment and surveillance, together with an in-depth review of the recommended algorithm for evaluation

    International criteria for electrocardiographic interpretation in athletes: Consensus statement.

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    Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly, advanced by a growing body of scientific data and investigations that both examine proposed criteria sets and establish new evidence to guide refinements. On 26-27 February 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington (USA), to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD

    Complete solution of a constrained tropical optimization problem with application to location analysis

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    We present a multidimensional optimization problem that is formulated and solved in the tropical mathematics setting. The problem consists of minimizing a nonlinear objective function defined on vectors over an idempotent semifield by means of a conjugate transposition operator, subject to constraints in the form of linear vector inequalities. A complete direct solution to the problem under fairly general assumptions is given in a compact vector form suitable for both further analysis and practical implementation. We apply the result to solve a multidimensional minimax single facility location problem with Chebyshev distance and with inequality constraints imposed on the feasible location area.Comment: 20 pages, 3 figure

    International Criteria for Reporting Study Quality for Sudden Cardiac Arrest/Death Tool

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    Background Studies reporting on the incidence of sudden cardiac arrest and/or death (SCA/D) in athletes commonly lack methodological and reporting rigor, which has implications for screening and preventative policy in sport. To date, there are no tools designed for assessing study quality in studies investigating the incidence of SCA/D in athletes. Methods and Results The International Criteria for Reporting Study Quality for Sudden Cardiac Arrest/Death tool (IQ‐SCA/D) was developed following a Delphi process. Sixteen international experts in sports cardiology were identified and invited. Experts voted on each domain with subsequent moderated discussion for successive rounds until consensus was reached for a final tool. Interobserver agreement between a novice, intermediate, and expert observer was then assessed from the scoring of 22 relevant studies using weighted and unweighted κ analyses. The final IQ‐SCA/D tool comprises 8 domains with a summated score of a possible 22. Studies are categorized as low, intermediate, and high quality with summated IQ‐SCA/D scores of ≤11, 12 to 16, and ≥17, respectively. Interrater agreement was “substantial” between all 3 observers for summated IQ‐SCA/D scores and study categorization. Conclusions The IQ‐SCA/D is an expert consensus tool for assessing the study quality of research reporting the incidence of SCA/D in athletes. This tool may be used to assist researchers, reviewers, journal editors, and readers in contextualizing the methodological quality of different studies with varying athlete SCA/D incidence estimates. Importantly, the IQ‐SCA/D also provides an expert‐informed framework to support and guide appropriate design and reporting practices in future SCA/D incidence trials

    What is progressive business?

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    This introductory chapter signposts the rationale, framework and case study contents of the book. Firstly, we offer an overview of the need for new more progressive business models than the mainstream which exists at present, identifying the current challenges facing business in Europe and beyond in its international ramifications. To remedy these challenges, we present our alternative vision of progressive business functioning, whose basic criteria comprise ecological sustainability, respect for future generations, and pro-socialness. Then, synopses of our case examples follow
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