Nash Equilibrium of a Fixed-Sum Two-Player Game

It is well established that Nash equilibrium exists within the framework of mixed strategies in strategic-form non-cooperative games. However, finding the Nash equilibrium generally belongs to the class of problems known as PPAD (Polynomial Parity Argument on Directed graphs), for which no polynomial-time solution methods are known, even for two-player games. This paper demonstrates that in fixed-sum two-player games (including zero-sum games), the Nash equilibrium forms a convex set, and has a unique expected payoff. Furthermore, these equilibria are Pareto optimal. Additionally, it is shown that the Nash equilibrium of fixed-sum two-player games can theoretically be found in polynomial time using the principal-dual interior point method, a solution method of linear programming.

Data Comparison between Elite and Amateur Soccer Players by 20 Hz GPS Data Collection

The athletic component in football is nowadays one of the most important factor to determinate the performance. This consideration is part of our study, which aims to evaluate and quantify the difference between the workload of an amateur footballer and an elite one. All this is allowed by match analysis made by GPS evaluation method for amateur and video tracking for elite. The examined teams were playing in 7th Italian league, and we used 10 GPS to track 6 games, 5 for each team. For every team and every game were analysed a forward, a central midfielder, a wide midfielder, a central defender and a full back （Age 25.3 ＋ 4.2, Weight 74.5 Kg a： 5.3, Height 1.76 cm ＋ 5.2）. In our study, we used a 20 Hz GPS （thanks to Advanced Research Group in Sport, School of Health and Sport Science with K-Sport Universal, Italy） to detect performance data, and then we compared the outcome with matches performance data from elite players gather from scientific literature. Data analysis shows that elite players reach higher values in almost all parameters taken into account. In particular, they obtained higher value in meters per minutes, High Speed Distance （〉 16 Km/h）, High Metabolic Power Distance （〉 20 W/Kg） and in high and very high and acceleration （2 m/s, 3 m/s, 〉 3 m/s） and deceleration （-2 m/s, -3 m/s, 〉 -3 m/s）. This study can be useful to select and catalogue player performance model, in order to better understand the real value of a player, and to help coaches and teams to identify talent, at least in physical values.

Correlation analysis of national elite Chinese male table tennis players’ shoulder proprioception and muscle strength

BACKGROUND Shoulder is the most injured part in table tennis players,and it takes multiple roles in transmitting power and striking the center of the ball during the stroke.Proprioception is strongly correlated with high level of athletic performance.It is customary to assume that there is a correlation between proprioception and muscle strength and therefore proprioceptive assessment and rehabilitation is often neglected.AIM To investigate the correlation between isokinetic muscle strength and proprioception in the internal and external rotation muscle groups of elite Chinese male table tennis players,to provide reference for physical training and rehabilitation of elite table tennis players.METHODS A total of 19 national elite table tennis players from the Chinese National Table Tennis Team were recruited in this research.All of them had more than 10 years training experience and had participated major competitions such as the National Games and World Youth Championships.IsoMed 2000 was used to test the peak torque of internal and external rotation isokinetic concentric contraction of the athletes'bilateral shoulder joints at low speed(60°/s)and high speed(180°/s)respectively;IsoMed 2000 was used to conduct the Joint Position Reproduction test to evaluate the athletes'proprioceptive ability capacity at low speed(60°/s)and high speed(180°/s)respectively.If the data satisfied the normal distribution,the correlation between the differences in peak torque s and angles in different directions was analyzed using a Pearson simple linear model;otherwise,Spearman correlation analysis was used.The comparison of proprioceptive ability between the table tennis racket-holding hand and non-racket-holding hands was performed using independent samples t-test if the data satisfied a normal distribution;otherwise,the Mann-Whitney U test was used.RESULTS There was no direct linear correlation between the strength and proprioceptive correlation analysis at slow speed(60°/s)and fast speed(180°/s)in the racket-holding hand;At the slow speed(60°/s)and fast speed(180°/s),there was no correlation between muscle strength and proprioception in the non-racket-holding hand except for the internal rotation variable error(VE)and external rotation relative peak torque,which showed a moderate positive correlation(r=0.477,P<0.05),(r=0.554,P<0.05).The internal rotation’s constant error(CE)and VE were 1.06±3.99 and 2.94±2.16,respectively,for the racket-holding hand,and-3.36±2.39 and 1.22±0.93,respectively,for the non-racket-holding hand;the internal rotation’s CE,VE of the racket-holding hand was lower than that of the non-racket-holding hand,and there was a highly significant difference(P<0.01).CONCLUSION There was no correlation between muscle strength and proprioceptive function in the internal and external rotation of the racket-holding hand’s shoulder in elite Chinese male table tennis players.These results may be useful for interventions for shoulder injuries and for the inclusion of proprioceptive training in rehabilitation programs.

Glycogen and amyloid-beta: key players in the shift from neuronal hyperactivity to hypoactivity observed in Alzheimer's disease?

Introduction：Alzheimer’s disease（AD）begins to develop decades prior to its clinical manifestation（Sperling et al.,2011）,and while it is the most common form of dementia,as of yet there is no cure.Two of the most researched pathological features contributing to disease development are the extracellular amyloid plaques composed of amyloid-beta proteins（Aβ）and neurofibrillary tangles of tau proteins.Another feature of AD is the progression of early neuronal excitability/hyperactivity to silencing/hypoactivity（Palop and Mucke,2010）,

The Distribution of Benefits for Players in Agricultural Industrial Chain

Players of the agricultural industrial chain pursue their own profit maximization,which can lead to conflicts of interest and affect the stability of the industrial chain. Therefore,fair and reasonable profit allocation mechanism is the key to guaranteeing the development and strengthening the strategic alliance relationship between participate members. Shapley model is an effective method to solve the profit distribution in cooperative relations. But it does not consider the three factors: risks faced by players during the operation of the agricultural industrial chain,technology innovation ability,and the degree of participating in the cooperation. So,correction factors are introduced to modify the Shapley value model,in order to make the distribution of benefits more equitable and reasonable,and effectively guide practice.

The Prevalence and Characteristics of Thoracic Outlet Syndrome in High School Baseball Players

Thoracic outlet syndrome (TOS) is one of the common neurovascular disorders of the upper extremities, and the compression or traction of the brachial plexus is the main pathology. We hypothesized that baseball players are more likely to be affected by TOS compared with other overhead-throwing athletes because of strenuous use of their throwing arm. The purpose of this study was to investigate the prevalence and clinical characteristics of TOS in high school baseball players. One thousand two hundred eighty-eight high school baseball players were included in this study. The prevalence of symptomatic TOS and its association to disorders of the upper extremities were investigated. The prevalence of symptomatic TOS was 32.8%. Age- and position-adjusted logistic regression analysis revealed that subjects with symptomatic TOS were at significantly higher risk of shoulder and/or elbow pain (odds ratio [OR]: 1.96, 95% confidence interval [CI]: 1.50 - 2.58) and a higher recurrence rate of shoulder and/or elbow pain during the previous season (OR: 2.38, 95% CI: 1.87 - 3.04). As for physical findings, subjects with symptomatic TOS were also at significantly higher risk of MUCL tenderness (OR: 2.53, 95% CI: 1.83 - 3.50), positive milking maneuver, (OR: 2.63, 95% CI: 1.78 - 3.91), positive subacromial impingement sign (OR: 1.92, 95% CI: 1.20 - 3.07), and positive posterior impingement sign (OR: 2.34, 95% CI: 1.67 - 3.28) compared to the subjects without symptomatic TOS. It is necessary to recognize that TOS is not a rare pathology in overhead-throwing athletes, especially baseball players, and that players with symptomatic TOS are at significantly higher risk of shoulder/elbow pain.

Differences in body components and electrical characteristics between youth soccer players and non-athletes

Many previous studies have focused on youth soccer player injuries without body component analysis compared to non-athletes. Only a few studies which have investigated body components of youth soccer players, and studies that look at electrical characteristics used by rheobase and chronaxie as well as body components are even scarcer. Therefore, we feel that there is a need for a study investigating objective clinical analysis of the body components (body structure and body composition) and electrical characteristics of both youth soccer players and non-athletes. Sixty subjects participated in our study, comprising of thirty youth soccer players and thirty non-athletes. The Inbody 520 was used to measure and analyze body composition and the Duo 500 was employed to measure electrical characteristics. It was observed that the soccer players showed markedly lower total impedance compared to the non-athletes. In both legs, it was particularly noted that there were significant differences between the right and left sides. The soccer players showed a higher skeletal muscle mass and lean/ideal lean × 100% compared to the non-athletes. Furthermore, the soccer players had a lower rheobase and higher chronaxie. A comparison of the genders showed a similar pattern. In this study, we were able to separate the differences in body components and electrical characteristics between the subject groups using a systemic approach. Future studies on diverse types of athletes would contribute further to the development of clinical physiotherapy and sports rehabilitation.

What factors are associated with premature death among professional baseball players in Japan?

The aim of this study is to clarify factors related to premature death among Japanese professional baseball players by a case-control analysis. The subjects are two matching groups of 622 Japan Professional Baseball (JPB) league players, those deceased and those surviving. Cases and controls are matched by birth year. All players debuted on the first string between 1934 and 2003, and are listed in The Official Baseball Encyclopedia of Japan. To compare means and frequencies of characteristics between deceased and surviving groups, t-tests and chi-square tests were used. A logistic regression analysis was assessed contributions of each independent variable on death. Significant differences between deceased and surviving players were observed in this study;deceased players had higher body mass indexes and longer careers. Furthermore, logistic regression analysis confirmed that body mass index and career length were statistically significant determinants of death for baseball players. This is the first report to examine factors of death for professional baseball players except employing data attained from Major League Baseball.

Association between Daily Living Walking Speed and Lifestyle and Physiological Factors in Older, Female Pokémon GO Players

Background: Walking speed is a reliable barometer of adverse health outcomes, particularly among older people. Few studies evaluated factors associated with daily actual walking speed, rather than that measured in a laboratory setting or self-reported data. Methods: In a joint effort with The Pokémon Company, we recruited study participants through a women’s magazine and analyzed data from 63 Pokémon GO players. We measured the true walking speed in daily life among older women using a data-gathering mobile application. Then, using questionnaire survey data collected on these participants in 2019, we estimated the relationship between walking speed and their lifestyle and physiological factors. In the analysis, we employed a bi-directional stepwise linear regression approach, with the Akaike information criterion (AIC) for variable selection. Results: The mean age of the 63 participants was 63.03 years (standard deviation, SD 7.46);the average walking speed was 4.56 km per hour (SD 1.54);and 52 (82.5%) and 55 (87.3%) participants answered that they had excellent/good health physically and mentally, respectively. After adjusted for covariates in a stepwise regression approach, we identified a significant association between −1.33 (95% confidence intervals −2.52 to −0.15) km/hour lower walking speed and the experience of outdoor falls within a year. We also demonstrated that the walking speed was 1.07 (0.33 to 1.81) km/hour faster for those who had played Pokémon GO before the study started. Conclusions: The true walking speed in daily life among older women was measured by a data-gathering mobile application. Although all participants were women recruited on a voluntary basis with an understanding of the purpose of the study, and the surveys were conducted at a cross-sectional setting, a significant relationship with the experience of outdoor falls was demonstrated. We also present evidence suggesting a possible relationship between Pokémon GO play and faster walking speed.

Minor Players, Major Drivers

If light is the way to dispel darkness,then Beijing-based Landsky Technology Group Co.,Ltd.narrates a bright and fascinating way of displaying optical technology.“Light is no longer just for illuminating objects.A well-designed lighting scheme can make people truly sense their surroundings,”Liang Ye,a senior manager at Landsky,said.Coming in from this perspective,the hi-tech enterprise in the field of lighting technology has focused its research and development(R&D)efforts on enriching the relationship between light and life,light and space,as well as that between light and nature.

Correlations of Handgrip Strength with Selected Anthropometric Variables and Flexibility Measure in Indian Inter-university Handball Players

The purpose of this study was of two-fold： firstly to estimate the handgfip strength oflndian inter-university handball players and, secondly to search the correlations of it with selected anthropometric variables and flexibility measure. To serve this purpose, a total of eight anthropometric variables, such as height, weight, body mass index, upper arm length, forearm length, total arm length, hand length and hand breadth, flexibility measure such as, sit and reach test, and right and left handgrip strength were measured on purposely selected 150 Indian inter-university handball players aged 18-25 years collected from the inter-university competition held in Guru Nanak Dev University, Amritsar, India during September, 2013. An adequate number of controls （n = 102） were also taken from the same place for comparisons. The results showed statistically significant between-group differences （P 〈 0.006-0.001） among the male and female handball players and controls in all the variables studied. Statistically significant positive correlations （P _〈 0.023-0.001） of both right and left handgrip strength were found with all the variables studied, except BMI, in Indian inter-university handball players. In conclusion, it may be stated that handgrip strength may be used as one of the indicating factors for physical strength as well as the flexibility measure of the handball players.

Analysis on the Physical Characteristics of High-level Football Players

This article uses the literature data method and literature review method to review and collect relevant literature,and summarizes and analyzes the representative views on domestic physical fitness research.After summarizing and summarizing,it is considered that:physical energy is the basic athletic ability of the human body expressed through physical qualities such as strength,speed,endurance,coordination,flexibility,and sensitivity,and is an important component of athletes'athletic ability.The level of physical fitness is closely related to the morphological characteristics of the human body and the functional characteristics of the human body.The morphological characteristics of the human body are the structural basis of its physical fitness,and the functional characteristics of the human body are its biological functional basis.As the basic ability of athletes,physical fitness is an important factor of athletes'competitive ability.Each competitive sport has its own specific physical characteristics and training rules and methods.Grasping these laws has very important guiding significance for the improvement of athletes'sports level.

Players＇ Perception on Game-Centered Approach in Coaching Female Soccer

Game-centered approach has become increasingly recognized in coaching with its potential for improving players＇ motivation and game performance. Since players are the centered component of this approach, players＇ perception can provide useful information for coaches in order to enhance cognitive learning of game play and improve game performance. Thus, the purpose of this study was to determine the players＇ perception for implementing the game-centered approach in coaching. Approximately 30 min of interviews with open-ended questions were conducted with five female collegiate soccer players. The game-centered approach helped participants to recognize their weaknesses and their strengths, to think more tactically and to adapt their performance from practices to competitions. Players were encouraged to tactically analyze their performance, emphasize cognitive learning of game play, and construct game knowledge. The cognitive learning helped players to easily transfer their game performance into competitions. Additionally, there was a positive impact on the players＇ motivation while they experienced enjoyment, challenges, and teamwork. Cognitive learning of game play, the performance adaptability for competitions, as well as the improving players＇ motivation was supported during the game-centered approach. Results provided helpful information for coaches to improve the effectiveness of practices which are truly useful to competitions.

ZTE Co-organized Global WiMAX Operation Congress in Singapore with Leading Industry Players

ZTE Corporation was among the key participants in the recently concluded WiMAX Operation Congress,

On appraisal models of basketball players'athletics a-bilities

Ｏｎａｐｐｒａｉｓａｌｍｏｄｅｌｓｏｆｂａｓｋｅｔｂａｌｌｐｌａｙｅｒｓ＇ａｔｈｌｅｔｉｃｓａ－ｂｉｌｉｔｉｅｓＬｉａｎｇＪｉａｎｐｉｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＰｈｙｓｉｃａｌＥｄｕｃａｔｉｏｎ，ＳｏｕｔｈｗｅｓｔＣｈｉｎａＮｏｒｍａｌＵｎｉｖｅｒ...

An Intial Study On the Training Of Point Man In Young Basketball Players

To train young point man is an important link in raising China′s basketball level.It consists of selecting good successors and train them. Criteria for the selection include ideology and behaviour, figure, physical fitness, type of nerves and genetic factors. The selection is conducted among 8 10-year-old children to find good successors.

Carving out a Niche African football players feature prominently in the Chinese leagues

The Chinese Football Association Super League （CSL） has broken yet another record. Indeed, the league＇s record recruitment budget of 388 million euros （$342.76 million） yeas broken this season. In 2018, more than 470 million euros （$415.19 million） have been spent on retaining the best football stars that have come to China in recent years, as well as on attracting even more talented footballers.

Research on the Space Construction of the Novel Ready Player One

The novel Ready Player One shows Ernest Cline’s ability of space construction,and demonstrates charm and artistic value of the virtual fantasy space it depicts.It is a science fiction with perfect combination of ideological content and artistic form.This thesis aims to discuss the Ernest Cline’s construction of the virtual pace and the real space in Ready Player One and the function of their construction.In real space,the environment is awful and dilapidated,and people’s lives are depressed.While in the virtual space,the world is colorful and people have varied ways of entertainment to fulfill their mind.This Thesis summarizes the effects brought by both the real space and virtual space for Ready Player One.With such a strong contrast,the conflict between the two spaces promotes the narrative process and also highlights the theme of the novel.

体教融合视域下青少年篮球运动员体能发展策略研究

体教融合对深入推动青少年体质健康和后备人才培养具有重要意义。篮球运动是一项高强度、多间歇、持续时间较长的项目,能够全面促进人体各项能力与素质发展。利用文献资料、逻辑分析等研究方法,对当前青少年篮球运动员体能训练的问题进行审视,发现学训矛盾依然存在、运动员积极性不高、训练缺乏科学性、训练资源不足等问题,并以问题为导向,从遵循青少年身心发展规律、遵循体能训练理论原则、遵循篮球运动项目特点、整合体能训练资源、创新体能训练模式5个方面,提出青少年篮球运动员体能发展策略,以期为研究学者提供有价值的参考。

CBA内线外援运动员选择分析

篮球运动员的竞技水平直接影响球队的比赛成绩与运营,因此选择什么样的运动员对球队至关重要。在CBA中,外援运动员的选择,尤其是内线外援运动员的选择是一直困扰CBA球队的问题。本文采用文献资料法、主成分分析法与K-均值聚类法等研究方法,从CBA某队备选的25名内线外援运动员中选择2名运动员(2号、18号)进行更进一步的考查(试训),然后运用t检验、方差分析等方法对2号和18号运动员的试训数据进行分析和预测,最终选择2号运动员作为球队主力内线(中锋)外援运动员。