Is playing ma-jong, chess and cards associated with a lower incidence of shoulder pain in Chinese elderly adults? The cross-sectional and longitudinal evidence from CHARLS.

BACKGROUND: The association between playing Ma-jong, chess and cards (PMCC) and shoulder pain among elderly adults in China remains unclear. The present study aimed to examine the association based on a nationally representative large-scale survey. METHODS: The study used two waves of data from China Health and Retirement Longitudinal Study (CHARLS) in 2015 and 2018. All subjects met the inclusion criteria were classified based on the results of the CHARLS wave questionnaire. Logistic regression models were conducted to analyze the cross-sectional and longitudinal association between PMCC and shoulder pain. Odds ratios (OR) were reported to indicate the strength of the association. RESULTS: In total, 8125 participants aged over 60 years (48.3 % male; mean age 67.9 ± 6.4 years) were enrolled in a cross-sectional association study in 2015, and further 6861 elderly adults were followed up in 2018. The overall prevalence of shoulder pain in the cross-sectional population was 15.6 %. In the non-PMCC and PMCC groups, the incidence of shoulder pain was 16.6 % and 10.7 %, respectively (P < 0.001). In the fully adjusted model, the results showed a significant association between PMCC and shoulder pain (OR: 0.798, 95 % CI: 0.662-0.963, P = 0.018). In the longitudinal analysis from 2015 to 2018, the incidence of new-occurrence shoulder pain in non-PMCC and PMCC groups was 22.1 %, and 18.5 %, respectively (P = 0.004). In the fully adjusted model, compared with the non-PMCC group, the risk of the occurrence of shoulder pain for individuals with PMCC was lower (OR: 0.832, 95 % CI: 0.709-0.975, P = 0.023). CONCLUSIONS: PMCC is associated with lower incidence of shoulder pain, which provides evidence for PMCC as a potential protective factor in the occurrence of shoulder pain.

Can the knight capture the queen? The role of supramarginal gyrus in chess rule-retrieval as evidenced by a novel combined awake brain mapping and fMRI protocol.

Brain tumours represent a burden for society, not only due to the risks they entail but also because of the possibility of losing relevant cognitive functions for the patient's life after their resection. In the present study, we report how we monitored chess performance through a multimodal Electrical Stimulation Mapping (ESM) - functional Magnetic Resonance Imaging (fMRI) combined protocol. The ESM was performed under a left parietal lobe tumour resection surgery on a patient that expressed the desire to preserve his chess playing ability post-operative. We designed an ad-hoc protocol to evaluate processes involved in chess performance that could be potentially affected by the tumour location: (i) visual search, (ii) rule-retrieval, and (iii) anticipation of checkmate. The fMRI study reported functional regions for chess performance, some of them proximal to the lesion in the left parietal lobe. The most relevant result was a positive eloquent point encountered in the vicinity of the left supramarginal gyrus while performing the rule-retrieval task in the ESM. This functional region was convergent with the activations observed in the pre-operative fMRI study for this condition. The behavioural assessment comparison revealed post-operative an increase in reaction time in some tasks but correctness in performance was maintained. Finally, the patient maintained the ability to play chess after the surgery. Our results provide a plausible protocol for future interventions and suggest a role of the left supramarginal gyrus in chess cognitive operations for the case presented.

How Time Pressure Modulates Individual Differences in the Functional Connectivity of Chunk Memory in Chess Games.

Previous studies on the chess game demonstrated that chess experts strongly rely on the activation of memory chunks to manifest accurate decision-making. Although the chunk memory might be affected by temporal constraints, it is unclear why the performance of chess experts is not significantly dropped under time pressure. In this study, our objective is to examine the variations in cognitive neural mechanisms between chess experts and novices under time pressure. The underlying cognitive neural mechanism was carefully inspected by accessing the chess game performance between 20 local experienced and 20 inexperienced chess players with 1-minute and 5-minute time constraints. In addition, functional near-infrared spectroscopy (fNIRS) recordings were carried out for each individual from the two groups while playing a 1-minute or 5-minute chess game. It was discovered that under temporal constraints, players exhibited different patterns of functional connectivity in frontal-parietal regions, suggesting that temporal stress can enhance segmentation processes in chess games. In particular, the experienced group exhibited significantly enhanced functional connectivity networks under time pressure including the dorsolateral prefrontal cortex, inferior frontal gyrus, supramarginal gyrus, and postcentral gyrus, which demonstrated the important role of the segmentation process for experienced players under time pressure. Our study found that experienced players were able to enhance recall, reorganize, and integrate chunks to improve chess performance under time pressure.

Economic and Humanistic Burden of Moderate and Severe Hemophilia A and B in Spain: Real-World Evidence Insights from the CHESS II Study.

Background: Hemophilia is a congenital disorder characterized by deficiency or absence of clotting factor VIII in hemophilia A (HA) or clotting factor IX in hemophilia B (HB), resulting in frequent, repeated, and prolonged spontaneous or traumatic bleeding into joints or soft tissue. Severity is classified by the patient's baseline level of clotting factor activity as mild (>5%-40%), moderate (1%-5%), or severe (<1%). In Spain, there is limited information on the societal economic burden of disease. Objective: To estimate the economic and humanistic burden of disease in adult patients with non-inhibitor moderate and severe HA and HB in Spain. Methods: Spanish data from the CHESS II study (2018-2020) on patients' clinical characteristics, health-related quality of life (HRQoL) and hemophilia-related healthcare resource utilization were analyzed. Economic burden was determined by estimating condition-related annual per-patient direct (medical and nonmedical) and indirect costs, stratified according to hemophilia type and severity and presented as 2022 Euros. HRQoL was assessed via the EQ-5D-5L. Results: Of 341 patients in the Spanish CHESS II cohort, 288 patients met the inclusion criteria: 181 had HA (37% [n = 66] moderate and 63% [n=115] severe) and 107 had HB (26% [n = 28] moderate and 74% [n = 79] severe). Mean annual direct cost was higher in HB than in HA, and higher in severe than in moderate patients, resulting in an annual cost/patient of €17 251 (moderate HA), €17 796 (moderate HB), €116 767 (severe HA) and €206 996 (severe HB). The main direct cost component in all groups except moderate HA was factor replacement therapy. Mean per-patient indirect cost was €4089 (moderate HA), €797 (moderate HB), €8633 (severe HA) and €8049 (severe HB). Finally, the mean total cost (direct and indirect) for moderate and severe patients were €91 017 (HA) and €163 924 (HB). EQ-5D-5L [SD] scores were lower in patients with severe HA (0.77 [0.18]) and severe HB (0.70 [0.22]) compared with patients with moderate HA (0.81 [0.15]) and moderate HB (0.86 [0.17]). Conclusions: Independently of the type of hemophilia, greater condition severity was associated with increased costs and a decrease in HRQoL.

MRI detection of mild malformation of cortical development with oligodendroglial hyperplasia (MOGHE) on T1WI-CHESS.

Mild malformation of cortical development with oligodendroglial hyperplasia (MOGHE) is a recently proposed epileptogenic entity that is difficult to detect on MRI. We present a case of MOGHE that was successfully detected on T1WI-chemical shift-selective saturation (CHESS) MRI. The clinical presentation, MRI including T1WI-CHESS, functional images, and pathology findings of a 14-year-old Japanese girl diagnosed with MOGHE are described. T1WI-CHESS revealed an abnormal high signal along the affected lesion, whereas the findings shown by the other MR sequences were less obvious; interictal fluorodeoxyglucose-positron emission tomography indicated slightly decreased accumulation in the lesion, and subtraction ictal single photon emission computed tomography co-registered to MRI showed an increased blood flow. Together these observations suggest that T1WI-CHESS may be a useful MR sequence for detecting the lesions in patients with MOGHE.

Effectiveness of a Serious Video Game (MOON) for Attention Deficit Hyperactivity Disorder: Protocol for a Randomized Clinical Trial.

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is the most common neurodevelopmental disorder in childhood and adolescence, with a prevalence of 5% and associated difficulties and worse prognosis if undetected. Multimodal treatment is the treatment of choice. However, sometimes treatment can be insufficient or have drawbacks. OBJECTIVE: This study protocol aims to demonstrate the effectiveness of cognitive training through the serious video game The Secret Trail of Moon (MOON) in improving emotional regulation in people with ADHD. METHODS: This is a prospective, unicenter, randomized, unblinded, pre- and postintervention study. The groups will be randomized (MOON vs control) via an electronic case report form. The MOON intervention will be performed 2 times per week for 10 weeks (30 minutes per session). The first 5 weeks (10 sessions) will be conducted face-to-face at the Puerta de Hierro University Hospital, and the remaining weeks will be conducted via the internet at the participants' homes. The total sample consists of 152 patients aged between 7 and 18 years. All participants have a clinical diagnosis of ADHD under pharmacological treatment. Data collection will be used to obtain demographic and clinical data. The data will be recorded using REDCap. Measures will be made through clinical scales for parents and objective tests of cognitive functioning in patients. Additional information on academic performance will be collected. The study has a power greater than 80% to detect differences. Student t test, 2-factor analysis of variance (ANOVA), and Mann-Whitney analyses will be performed according to each variable's characteristics. RESULTS: The study was approved by the Research Ethics Committee of the Puerta de Hierro University Hospital on December 14, 2022. As of September 26, 2023, we have enrolled 62 participants, and 31 participants have completed the study. This clinical trial was funded by the Comunidad de Madrid (IND2020/BMD-17544). The approximate completion date is March 2024. CONCLUSIONS: Serious video games such as MOON can be motivational tools that complement multimodal treatment for ADHD. TRIAL REGISTRATION: ClinicalTrials.gov; NCT06006871; https://clinicaltrials.gov/study/NCT06006871. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53191.

Cultural transmission of move choice in chess.

The study of cultural evolution benefits from detailed analysis of cultural transmission in specific human domains. Chess provides a platform for understanding the transmission of knowledge due to its active community of players, precise behaviours and long-term records of high-quality data. In this paper, we perform an analysis of chess in the context of cultural evolution, describing multiple cultural factors that affect move choice. We then build a population-level statistical model of move choice in chess, based on the Dirichlet-multinomial likelihood, to analyse cultural transmission over decades of recorded games played by leading players. For moves made in specific positions, we evaluate the relative effects of frequency-dependent bias, success bias and prestige bias on the dynamics of move frequencies. We observe that negative frequency-dependent bias plays a role in the dynamics of certain moves, and that other moves are compatible with transmission under prestige bias or success bias. These apparent biases may reflect recent changes, namely the introduction of computer chess engines and online tournament broadcasts. Our analysis of chess provides insights into broader questions concerning how social learning biases affect cultural evolution.

The Gender-Equality Paradox in Chess Participation Is Partially Explained by the Generational-Shift Account but Fully Inconsistent With Existing Alternative Accounts: A Partial Concession and Reply to Napp and Breda (2023).

Napp and Breda (2023) raised three arguments against the generational-shift account of the gender-equality paradox (GEP) in chess participation. First, using finer operationalizations of the age structure of players, they showed that it partially but not fully accounts for the GEP in chess participation. I find merit in these analyses and conclusion. Second, they argued that the country-level age structure is unrelated to the GEP in chess participation, which undermines the generational-shift account of the GEP. In contrast, I provide new analyses to show that the two are related after adjusting for the U-shaped relation between gender equality and female chess participation. Finally, they argued that previous explanations of the GEP are viable for explaining the GEP in chess participation. In contrast, I argue that the global increase in the proportion of female players is incompatible with previous explanations of the GEP, and I provide new analyses to support this.

Household food insecurity during the COVID-19 pandemic and associated socioeconomic demographic factors in Papua New Guinea: evidence from the Comprehensive Health and Epidemiological Surveillance System.

INTRODUCTION: The COVID-19 pandemic had an unprecedented impact on global food security, but little is known about the impact on food security at the household level. We examined the prevalence and socioeconomic demographic factors for household food insecurity during the COVID-19 pandemic in Papua New Guinea. METHODS: Household socioeconomic demographic data from the Comprehensive Health and Epidemiological Surveillance System were collected from six main provinces in 2020 (37880 participants) and compared with the 2018 data (5749 participants). The prevalence of household food insecurity was estimated and stratified by household socioeconomic demographic characteristics. Multinomial logistic regression was conducted to estimate adjusted OR (aOR) and 95% CI of risk factors. RESULTS: The overall prevalence of household food insecurity increased from 11% in 2018 to 20% in 2020, but varied across provinces, with the highest level reported in Central Province (35%) and the lowest level in East New Britain Province (5%).Food shortages were 72% less likely among urban residents than those living in rural areas (aOR 0.28 (95% CI 0.21 to 0.36)). The risk of food insecurity was 53% higher among adults aged 25+ years with primary education (grades 3-8) than those with university education (aOR 1.53 (95% CI 1.09 to 2.13)). People from households in the poorest wealth quintiles were 80% more likely to report food shortage than those from the richest wealth quintile (aOR 1.78 (95% CI 1.29 to 2.45). CONCLUSION: The study provides evidence to develop policy and intervention to deal with food insecurity in emergency situations in the future.

On the Value of Chess Squares.

We propose a neural network-based approach to calculate the value of a chess square-piece combination. Our model takes a triplet (color, piece, square) as the input and calculates a value that measures the advantage/disadvantage of having this piece on this square. Our methods build on recent advances in chess AI, and can accurately assess the worth of positions in a game of chess. The conventional approach assigns fixed values to pieces (= ∞, = 9, = 5, = 3, = 3, = 1). We enhance this analysis by introducing marginal valuations. We use deep Q-learning to estimate the parameters of our model. We demonstrate our method by examining the positioning of knights and bishops, and also provide valuable insights into the valuation of pawns. Finally, we conclude by suggesting potential avenues for future research.

The role of chess in the development of children-parents' perspectives.

Introduction: The study examines the role of chess in the development of children from the perspectives of parents. The research focused on analyzing the parents' perceptions about chess's role in their children's development, on finding out how the perception of parents differs depending on whether they know how to play chess or not, and on outlining the profile of the parents whose children play chess.The study was conducted in Romania. Methods: In order to conduct the study, a quantitative research method was used, while having as a research instrument a non-standardized questionnaire. The questionnaire was applied to parents of chess-playing children who are members of chess clubs from Romania. The sample of the study comprises 774 respondents. Results: The results of our research showed that parents are of the opinion that chess helps children develop their cognitive abilities, their character and their competitive spirit. Most of the parents focused on highlighting the positive effects of chess on the development of their children. Parents also considered that chess helped their children develop positive emotions and helped them overcome negative emotions. The results revealed differences between the opinions of parents depending on whether they know how to play chess or not. Thus, parents who do know how to play chess were more likely to focus on the positive effects of the game on the development of their children, and those who know how to play chess were also more satisfied with their children's accumulated knowledge following chess lessons. Discussion: Findings extend our understanding of how parents perceive the way chess influences the development of their children, it offered us a perspective on the perceived benefits of chess, benefits which should be further analyzed in order to identify under what circumstances chess could be introduced in the school curriculum.

The effect of the leisure activities based on chess and cards for improving cognition of older adults: study protocol for a cluster randomized controlled trial.

BACKGROUND: With the increase in age, the probability of cognitive impairment in the older people is increasing. More and more evidence shows that participating in leisure activities, especially chess and cards, is beneficial to the cognition and mental state of the older people. But the evidence for causal inference is limited. There is a need to conduct a fully powered randomized controlled trial (RCT) and long-term follow-up to test the effectiveness of intervention measures in improving cognitive function and mental state. This paper describes the methodology of a cluster RCT designed to determine the effect of chess and cards leisure activities on the cognitive function of the older people over 60 years old. METHODS/DESIGN: A cluster RCT consisting of 8 clusters will be conducted in four regions of Ningxia, China (Helan, Litong, Qingtongxia, and Shapotou). Clusters will be randomly assigned to the advocacy intervention group, which is also delivered with free leisure activities tools (chess and cards), or the control group. A baseline survey will be conducted before the intervention. A mid-term and final survey will be carried out twelve and twenty-four months after the intervention, respectively. The primary outcome is a change in cognitive function, and the secondary outcomes are changes in anxiety, depression, and loneliness. DISCUSSION: The results of this RCT will be helpful to (1) confirm the effectiveness of chess and cards leisure activities in improving the cognitive function of the older people over 60 years old; (2) determine the relationship between the frequency and duration of chess and cards leisure activities and cognitive function; (3) provide evidence of promoting participation in leisure activities through education campaigns and free provision of chess and cards tools; and (4) provide valuable information for successful aging. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR2200066817. Registered on 19 December 2022.

Acceptance and Commitment Therapy for improving the performance of chess players suffering from anxiety disorders

Previous research has suggested that brief protocols based on acceptance and commitment therapy (ACT) are efficacious in improving elite chess players' performance without clinical problems. These promising results warranted the examination of the effect of longer ACT interventions with chess players suffering from emotional difficulties. This study advances in this direction by presenting two case studies of elite chess players experiencing anxiety disorders. Each participant was matched to a control participant with similar characteristics. The ACT interventions were conducted in 5 sessions and with occasional follow-ups during the following year. The primary dependent variable was an objective measure of chess performance (ELO Performance). Data analysis was conducted using the JZS+AR Bayesian hypothesis testing for single-case designs and the nonparametric Tau-U statistic. Control participants did not significantly improve their chess performance during the follow-up, but chess players who received the intervention showed significant increases in their performance. Both treated participants experienced clinically significant reductions in symptomatology and improved valued living after the intervention. This study provides empirical evidence regarding the potential benefit of applying ACT to improve chess performance in players with clinical problems (AU)

Natural sciences and chess: A romantic relationship missing from higher education curricula.

Chess is a game that delicately weaves analytical thinking around artistic experience, yet recent conversions of STEM (Science-Technology-Engineering-Mathematics) to STEAM (Science-Technology-Engineering-Art-Mathematics) have omitted adding chess as an elementary coursework to K-12 and higher education curricula. Chess, as per arguments presented in this essay, can be considered as a language and a tool for furthering the development of artistic skills among scientists and analytical, pattern-recognition skills among artists. It can also serve as a missing link between science and art in STEAM curricula thanks to its finding itself halfway between the two. A handful of analogies are drawn here from chess, illustrated sporadically with positions from real-life chess games and converted to lessons in creativity for students in natural sciences. The discussion centered around these analogies is reinforced by a literature review of studies conducted over the past 80 years to assess the effect of exposing students to lessons in chess on their learning in distant domains. Overall, great benefits can emerge from complementing science education with chess and it is hoped that chess will become an integral part of basic education in primary schools and universities worldwide in the near future.

Effectiveness of a Personalized, Chess-Based Training Serious Video Game in the Treatment of Adolescents and Young Adults With Attention-Deficit/Hyperactivity Disorder: Randomized Controlled Trial.

BACKGROUND: Compared with traditional approaches, gaming strategies are promising interventions for the treatment of attention-deficit/hyperactivity disorder (ADHD). We developed a serious game, The Secret Trail of Moon (TSTM), for ADHD treatment. OBJECTIVE: The main objective of this clinical trial was to demonstrate the effectiveness of an add-on, either TSTM or Therapeutic Chess (TC), in previously optimally drug-titrated, clinically stable patients with ADHD. METHODS: This study is a prospective, unicentric, randomized clinical trial in clinically stable patients with ADHD, aged 12 to 22 years. The TSTM (n=35) and TC groups (n=34) performed 12 weekly sessions of their respective treatments. The control group (CG) patients (n=35) were called by phone every week, but they received no cognitive intervention. The primary end point was the change from baseline to end point in the parent "Behavior Rating Inventory of Executive Function-2" (BRIEF-2; patients' parents) in the per-protocol population (31 serious videogame: 24 TC and 34 CG). RESULTS: Our study failed to probe clear-cut improvements in the global score of the BRIEF-2. However, the TC group showed improvements in measures of emotional control, emotional regulation, and inattention. The TSTM group showed improvements in measures of emotional regulation, inattention, and school context. CONCLUSIONS: TSTM and TC did not improve executive function symptoms, but they improved ADHD symptomatology related to emotional regulation. Further studies with bigger samples are required to confirm these preliminary findings. TRIAL REGISTRATION: ClinicalTrials.gov NCT04355065; https://clinicaltrials.gov/ct2/show/NCT04355065.

Juegos pequeños con nociones de ajedrez para el desarrollo de las habilidades motrices básicas en la Educación Física

El juego es una forma natural de aprender, ya que incluye elementos de aprendizaje en interacción con lo lúdico. Específicamente el juego de ajedrez, se aplica en el sistema educativo de algunos países como un instrumento multidisciplinario, pues ayuda en el desarrollo del pensamiento cognitivo, la planificación, la imaginación, la anticipación, el autocontrol, la toma de decisiones, la creatividad y la inteligencia. En ese sentido, los profesores de Educación Física del 2do grado de la Escuela Primaria 1728, en el barrio Tchioco, en Lubango presentaron dificultades en la aplicación de métodos que permitan el desarrollo de las habilidades motrices básicas de manera atractiva a sus alumnos. De ahí que el objetivo de esta investigación consistió en proponer juegos pequeños con nociones de ajedrez para el mejoramiento de las habilidades motrices básicas, en los alumnos antes mencionados. Para ello, se efectuó un estudio descriptivo, no experimental, de corte transversal y se emplearon métodos científicos del nivel teórico como el analítico-sintético, inducción-deducción, histórico-lógico y funcional-sistémico-estructural y del nivel empírico como la revisión de documentos, la observación y la entrevista; así como el cálculo porcentual para el análisis de los datos arrojados. Los resultados obtenidos permitieron caracterizar el estado de desarrollo del objetivo propuesto y adecuar la propuesta de juegos elaborada.

SÍNTESE O jogo é uma forma natural de aprendizagem, pois inclui elementos de aprendizagem em interação com o jogo. Especificamente, o jogo de xadrez é aplicado no sistema educacional de alguns países como um instrumento multidisciplinar, pois ajuda no desenvolvimento do pensamento cognitivo, planejamento, imaginação, antecipação, autocontrole, tomada de decisões, criatividade e inteligência. Neste sentido, os professores de Educação Física da 2ª série do Ensino Fundamental 1728, no bairro de Tchioco, em Lubango, apresentaram dificuldades na aplicação de métodos que permitem o desenvolvimento de habilidades motoras básicas de forma atrativa para seus alunos. Assim, o objetivo desta pesquisa consistiu em propor pequenas partidas com noções de xadrez para a melhoria das habilidades motoras básicas dos alunos acima mencionados. Para este fim, foi realizado um estudo descritivo, não-experimental, transversal e descritivo e foram utilizados métodos científicos a nível teórico, tais como analítico-sintético, indução-dedução, histórico-lógico e funcional-sistêmico-estrutural, e a nível empírico, tais como revisão de documentos, observação e entrevista, bem como cálculo percentual para a análise dos dados obtidos. Os resultados obtidos tornaram possível caracterizar o estado de desenvolvimento do objetivo proposto e adaptar a proposta de jogo elaborada.

The game is a natural way of learning, since it includes elements of learning in interaction with play. Specifically, the game of chess is applied in the educational system of some countries as a multidisciplinary instrument, since it helps in the development of cognitive thinking, planning, imagination, anticipation, self-control, decision-making, creativity and intelligence. In this sense, the Physical Education teachers of the 2nd grade of the 1728 Elementary School, in the Tchioco neighborhood, in Lubango presented difficulties in the application of methods that allow the development of basic motor skills in an attractive way for their students. Hence, the objective of this research was to propose small games with notions of chess for the improvement of basic motor skills in the aforementioned students. For this, a descriptive, non-experimental, cross-sectional study was carried out and scientific methods were used at the theoretical level such as analytical-synthetic, induction-deduction, historical-logical and functional-systemic-structural and at the empirical level such as the review of documents, observation and interview; as well as the percentage calculation for the analysis of the data obtained. The results obtained allowed to characterize the state of development of the proposed objective and to adapt the proposal of games elaborated.

[Origin, development, and modern application value of Chinese herbal lozenges].

Lozenge is one of the traditional dosage forms of Chinese medicine. It has been recorded in traditional Chinese medical classics of all dynasties since the Eastern Han Dynasty and has been developing and evolving continuously. The unique pharmaceutical methods and application scope are the driving force of its emergence, existence, and development. Up to now, lozenge has been included in the Chinese Pharmacopoeia as an independent dosage form. Lozenge has been endowed with new meaning by modern Chinese medicine pharmaceutics, which is worth tracing origin and exploring value. The present study reviewed the origin and development of lozenge, compared lozenge with other similar dosage forms, analyzed the characteristics of modern and ancient dosage forms of lozenge, and discussed the development prospect and potential of lozenge in combination with the demand development of modern Chinese medicine preparation, so as to provide references for expanding the modern application of lozenge.

KIBRA Gene Variant Is Associated with Ability in Chess and Science.

The kidney and brain expressed protein (KIBRA) plays an important role in synaptic plasticity. Carriers of the T allele of the KIBRA (WWC1) gene rs17070145 C/T polymorphism have been reported to have enhanced spatial ability and to outperform individuals with the CC genotype in working memory tasks. Since ability in chess and science is directly related to spatial ability and working memory, we hypothesized that the KIBRA T allele would be positively associated with chess player status and PhD status in science. We tested this hypothesis in a study involving 2479 individuals (194 chess players, 119 PhD degree holders in STEM fields, and 2166 controls; 1417 males and 1062 females) from three ethnicities (236 Kazakhs, 1583 Russians, 660 Tatars). We found that frequencies of the T allele were significantly higher in Kazakh (66.9 vs. 55.1%; p = 0.024), Russian (44.8 vs. 32.0%; p = 0.0027), and Tatar (51.5 vs. 41.8%; p = 0.035) chess players compared with ethnically matched controls (meta-analysis for CT/TT vs. CC: OR = 2.05, p = 0.0001). In addition, none of the international chess grandmasters (ranked among the 80 best chess players in the world) were carriers of the CC genotype (0 vs. 46.3%; OR = 16.4, p = 0.005). Furthermore, Russian and Tatar PhD holders had a significantly higher frequency of CT/TT genotypes compared with controls (meta-analysis: OR = 1.71, p = 0.009). Overall, this is the first study to provide comprehensive evidence that the rs17070145 C/T polymorphism of the KIBRA gene may be associated with ability in chess and science, with the T allele exerting a beneficial effect.

The influence of schooling on performance in chess and at the Olympics.

At the macro-level, it is hard to test the hypothesis that increased schooling in a country will raise labour productivity but sectoral analyses may be tractable. In sports, output is homogenous in that countries' achievements are measurable in the same way. We examine country performances at the Chess Olympiad and the Olympic Games, contrasting tournaments where players in the first use only their minds but most in the second supply substantial physical effort or work with costly physical capital. Modelling success in either leads to a set of results familiar from sports literature: country performance depends on economic resources, represented by population size and per capita income. Supplementary variables capture over-performance by communist/ former communist countries. We then introduce a measure of average years of schooling. This significantly reduces the role of income, especially in chess. It also takes power away from the 'communist' variables, especially at the Olympics. These results suggest that much of any effect from income is mediated through schooling: investment in education is associated with elevated productivity. Increased productivity is observed in both settings, one a knowledge-intensive sub-sector and the other dependent to a significant extent on either raw physical strength or expensive capital input. Supplementary Information: The online version contains supplementary material available at 10.1007/s00181-022-02259-9.