Pre-, Per- and post-cooling strategies used by competitive tennis players in hot dry and hot humid conditions.

Purpose: This research investigated the pre-, per- and post cooling strategies used by competitive tennis players from various levels of play who occasionally train and compete in hot (>28°C) and humid (>60% rH), and dry (<60% rH) environments.

Methods: 129 male tennis players (M = 24.9) competing at regional ( = 54), national ( = 30) and international ( = 45) levels, completed an online questionnaire regarding their use (i.

Retirements of professional tennis players in ATP and WTA tour events.

Professional tennis competition at the highest levels requires high physical, technical, tactical, and mental demands. Player retirement is a scenario that often occurs at the highest echelons of the game. The objective of this study was to descriptively determine which factors influence retirement of matches in tennis.

Determining the tactical and technical level of competitive tennis players using a competency model: a systematic review.

Introduction: The aim of this systematic review is to provide an evidence-based synthesis of the literature on the topic of technical and tactical competencies of tennis players and to answer the following research questions: (1) What is the state of the art of research on technical and tactical competencies (i.e., skills and knowledge) and tennis; (2) What are the most important topics related to technical and tactical competencies in tennis players.

Retirements of professional tennis players in second- and third-tier tournaments on the ATP and WTA tours.

The demands of professional tennis, including physical and psychological aspects, contribute to the frequency of retirements at elite levels of the sport. The aim of this study was to analyze epidemiological patterns and risk factors associated with retirements in previous ATP and WTA Tour tournaments. A retrospective cohort study was conducted.

Quantifying Hitting Load in Racket Sports: A Scoping Review of Key Technologies.

Purpose: This scoping review aims to identify the primary racket and arm-mounted technologies based on inertial measurement units that enable the quantification of hitting load in racket sports.

Methods: A comprehensive search of several databases (PubMed, SPORTDiscus, Web of Science, and IEEE Xplore) and Google search engines was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) extension for scoping reviews guidelines. Included records primarily focused on monitoring hitting load in racket sports using commercialized racket or arm-mounted inertial sensors through noncompetitive and competitive racket-sports players.

How do International Olympic Sport Federations innovate? The use of crowdfunding and the impact of COVID-19.

The purpose of this study was to contribute to the understanding of innovation and crowdfunding of International Olympic Sport Federations (IFs), which are the world governing bodies of their respective sports. Three research questions were addressed: the perceptions of the IFs on the implementation of their innovation programmes during the last four years (2016-2020), the impact of COVID-19 on the IFs capability to innovate, and the crowdfunding strategies of the IFs. A mixed method combining qualitative and quantitative approaches was used.

Heart Rate Variability in Elite International ITF Junior Davis Cup Tennis Players.

The aim of the present study was to investigate the evolution of the HRV during an international team tennis tournament in elite junior tennis players. A total of 11 tennis players, with a mean age of 15.36 (0.

Non-line-of-sight imaging in the presence of scattering media using phasor fields.

Non-line-of-sight (NLOS) imaging aims to reconstruct partially or completely occluded scenes. Recent approaches have demonstrated high-quality reconstructions of complex scenes with arbitrary reflectance, occlusions, and significant multi-path effects. However, previous works focused on surface scattering only, which reduces the generality in more challenging scenarios such as scenes submerged in scattering media.

Impact of match-induced pressure on HRV of junior tennis players.

The present study aimed to assess the impact of a tennis competition on the HRV of nationally ranked junior girls and boys tennis players. A total of 22 nationally ranked tennis players (8 girls and 14 boys), with a mean age of 14.18 (2.

COVID-19 Prevention Measures Implemented by Tennis Coaches: The Role of Continent, Experience, and Type of Facility.

The prevention strategies used by tennis coaches when delivering tennis lessons during the COVID-19 pandemic were analyzed in this study. An ad hoc questionnaire collected data from 655 Spanish and Portuguese speaking tennis coaches working in Latin America and Europe. Differences in the prevention measures were analyzed according to the continent, the coaches' experience, and the type of facility they worked in.

Key Physical Factors in the Serve Velocity of Male Professional Wheelchair Tennis Players.

The aim of this study was to identify the physical factors related to serve speed in male professional wheelchair tennis players (WT). Nine best nationally-ranked Spanish male wheelchair tennis players (38.35 ± 11.

Genome-scale screens identify JNK-JUN signaling as a barrier for pluripotency exit and endoderm differentiation.

Human embryonic stem cells (ESCs) and human induced pluripotent stem cells hold great promise for cell-based therapies and drug discovery. However, homogeneous differentiation remains a major challenge, highlighting the need for understanding developmental mechanisms. We performed genome-scale CRISPR screens to uncover regulators of definitive endoderm (DE) differentiation, which unexpectedly uncovered five Jun N-terminal kinase (JNK)-JUN family genes as key barriers of DE differentiation.

A hPSC-based platform to discover gene-environment interactions that impact human β-cell and dopamine neuron survival.

Common disorders, including diabetes and Parkinson's disease, are caused by a combination of environmental factors and genetic susceptibility. However, defining the mechanisms underlying gene-environment interactions has been challenging due to the lack of a suitable experimental platform. Using pancreatic β-like cells derived from human pluripotent stem cells (hPSCs), we discovered that a commonly used pesticide, propargite, induces pancreatic β-cell death, a pathological hallmark of diabetes.

Discovery of a drug candidate for GLIS3-associated diabetes.

GLIS3 mutations are associated with type 1, type 2, and neonatal diabetes, reflecting a key function for this gene in pancreatic β-cell biology. Previous attempts to recapitulate disease-relevant phenotypes in GLIS3 β-like cells have been unsuccessful. Here, we develop a "minimal component" protocol to generate late-stage pancreatic progenitors (PP2) that differentiate to mono-hormonal glucose-responding β-like (PP2-β) cells.

Corrigendum: Colonic organoids derived from human induced pluripotent stem cells for modeling colorectal cancer and drug testing.

This corrects the article DOI: 10.1038/nm.4355.

Technical, tactical and movement analysis of men's professional tennis on hard courts.

Background: There is very little information in tennis relating performance to both the movement of the players and the effectiveness of their shots. This study aimed to identify differences between winners and losers in the volume and intensity of their movements, as well as in the effectiveness of their shots.

Methods: Matches (N.

Colonic organoids derived from human induced pluripotent stem cells for modeling colorectal cancer and drug testing.

With the goal of modeling human disease of the large intestine, we sought to develop an effective protocol for deriving colonic organoids (COs) from differentiated human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs). Extensive gene and immunohistochemical profiling confirmed that the derived COs represent colon rather than small intestine, containing stem cells, transit-amplifying cells, and the expected spectrum of differentiated cells, including goblet and endocrine cells. We applied this strategy to iPSCs derived from patients with familial adenomatous polyposis (FAP-iPSCs) harboring germline mutations in the WNT-signaling-pathway-regulator gene encoding APC, and we generated COs that exhibit enhanced WNT activity and increased epithelial cell proliferation, which we used as a platform for drug testing.

Distinct mechanisms regulate Cdx2 expression in the blastocyst and in trophoblast stem cells.

The first intercellular differences during mammalian embryogenesis arise in the blastocyst, producing the inner cell mass and the trophectoderm. The trophectoderm is the first extraembryonic tissue and does not contribute to the embryo proper, its differentiation instead forming tissues that sustain embryonic development. Crucial roles in extraembryonic differentiation have been identified for certain transcription factors, but a comprehensive picture of the regulation of this early specification is still lacking.

Modeling Cystic Fibrosis Using Pluripotent Stem Cell-Derived Human Pancreatic Ductal Epithelial Cells.

Unlabelled: We established an efficient strategy to direct human pluripotent stem cells, including human embryonic stem cells (hESCs) and an induced pluripotent stem cell (iPSC) line derived from patients with cystic fibrosis, to differentiate into pancreatic ductal epithelial cells (PDECs). After purification, more than 98% of hESC-derived PDECs expressed functional cystic fibrosis transmembrane conductance regulator (CFTR) protein. In addition, iPSC lines were derived from a patient with CF carrying compound frameshift and mRNA splicing mutations and were differentiated to PDECs.