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Azevedo RA, Gualano B, Teixeira TA, Nascimento BCG, Hallak J. Abusive use of anabolic androgenic steroids, male sexual dysfunction and infertility: an updated review. Front Toxicol 2024; 6:1379272. [PMID: 38711907 PMCID: PMC11070513 DOI: 10.3389/ftox.2024.1379272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 04/09/2024] [Indexed: 05/08/2024] Open
Abstract
The evolving prevalence of anabolic androgenic steroids (AAS) abuse among nonathletes is alarming because of the known harm to an individual's health. Among the adverse effects of AAS abuse, male infertility and sexual dysfunction have been often reported in the literature, but little is known regarding its actual prevalence, possible underpinning mechanisms, and potential treatments either during or post-AAS usage. Thus, the current narrative review summarizes the state-of-art regarding the effects of AAS on male fertility and sexual function. Evidence was gathered from the latest reviews and recent original studies, specifically from prospective cohorts and clinical trials, ultimately resulting in five main topics of discussion. First, AAS usage is briefly characterized by its historical background, main physiological mechanisms, and the most frequently used AAS substances. Second, data on the prevalence of AAS-induced male infertility and sexual dysfunction are described. Third, some new insights on possible underpinning mechanisms of AAS-induced male infertility and sexual dysfunction are thoroughly discussed, with particular attention to histological data derived from animal models and the latest insights from prospective cohorts in humans. Fourth, the potential treatments during and after the AAS usage are presented, highlighting the odds of resolving male infertility and sexual dysfunction. Fifth, future directions on this topic are discussed, focusing on the methodological robustness of scientific studies.
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Affiliation(s)
- Rafael de Almeida Azevedo
- Applied Physiology and Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
| | - Bruno Gualano
- Applied Physiology and Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
| | - Thiago Afonso Teixeira
- Division of Urology, Department of Surgery, University Hospital, School of Medicine and Drug Research Laboratory, Federal University of Amapa, Macapá, Brazil
- Men’s Health Study Group, Institute for Advanced Studies, University of Sao Paulo, São Paulo, Brazil
- Androscience Institute for Science, Education and Advanced Projects in Male Health, São Paulo, Brazil
| | | | - Jorge Hallak
- Men’s Health Study Group, Institute for Advanced Studies, University of Sao Paulo, São Paulo, Brazil
- Androscience Institute for Science, Education and Advanced Projects in Male Health, São Paulo, Brazil
- Division of Urology, Department of Surgery, University of Sao Paulo, São Paulo, Brazil
- Androscience—Science and Innovation Center and High Complexity Clinical and Research Andrology Laboratory, São Paulo, Brazil
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Thomas D, Shabeek AA, Ahmed H, Mohammed M, Kawaguchi-Suzuki M, Anderson A, Gopakumar A, Alhosani R, Khalifa S, Mottram D. Impact of an educational flyer and sensitization on performance-enhancement attitudes of bodybuilders in United Arab Emirates. F1000Res 2024; 12:208. [PMID: 38533422 PMCID: PMC10964001 DOI: 10.12688/f1000research.130700.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/12/2024] [Indexed: 09/01/2023] Open
Abstract
Background A high proportion of bodybuilders use supplements to improve performance, with some turning to prohibited substances and methods. The attitudes of bodybuilders towards performance enhancement may be gauged through surveys such as the Performance Enhancement Attitude Scales (PEAS). Educational interventions are recommended as part of anti-doping measures. The objective of this project was to assess the impact of a pharmacy-led intervention using an antidoping educational flyer and the performance enhancement attitude scale to measure the attitude of bodybuilders in the United Arab Emirates (UAE). Methods The PEAS eight-item short form questionnaire was administered to male bodybuilders in the UAE. The PEAS was conducted before and after administration of an educational flyer concerning the problems associated with supplement use among bodybuilders. The Wilcoxon Signed-Rank and Kruskal Wallis tests were used for data analysis. Results A total of 218 bodybuilders, who reported taking dietary supplements, filled out the survey both pre and post viewing the antidoping educational flyer. A difference was observed between the full-time professional bodybuilders, students, and part-time bodybuilders with other primary occupations (p-value <0.05). In addition, PEAS score decreased among the study population for all eight PEAS items (p-value <0.05). Conclusions The pharmacy-led intervention using an antidoping educational flyer and sensitization by PEAS achieved more favorable scores, suggesting a significant shift of opinion toward avoiding use of performance enhancing substances among the bodybuilder study population. More research is required on sustaining the attitude and demonstrating the impact on doping behavior.
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Affiliation(s)
- Dixon Thomas
- College of Pharmacy, Gulf Medical University, Ajman, United Arab Emirates
| | | | - Hala Ahmed
- College of Pharmacy, Gulf Medical University, Ajman, United Arab Emirates
| | - Malak Mohammed
- College of Pharmacy, Gulf Medical University, Ajman, United Arab Emirates
| | | | | | - Aji Gopakumar
- Department of Research, Emirates Health Services, Dubai, United Arab Emirates
| | | | - Sherief Khalifa
- College of Pharmacy, Gulf Medical University, Ajman, United Arab Emirates
| | - David Mottram
- Pharmacy and pharmaceutical science, Liverpool John Moores University, Liverpool, UK
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Friehs MA, Klarkowski M, Frommel J, Phillips C, Mandryk RL. Fighting fair: community perspectives on the fairness of performance enhancement in esports. Front Sports Act Living 2024; 6:1330755. [PMID: 38532852 PMCID: PMC10963441 DOI: 10.3389/fspor.2024.1330755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 03/04/2024] [Indexed: 03/28/2024] Open
Abstract
Aims This study aims to explore community perspectives on enhancer usage in competitive gaming and esports, focusing on the perception of fairness and concerns about various potential performance enhancers. Methods We conducted both qualitative and quantitative surveys to understand the competitive gaming community's opinions on different types of performance enhancers and their potential impact on esports. A thematic analysis was performed to identify key themes in how players rationalize their opinions. Conclusions The gaming community differentiates between potential performance enhancers based on how problematic they are for the esports scene, with the most concern surrounding hard drugs, pharmaceuticals, and brain stimulation interventions. Participants who are more invested in competitive gaming tend to be more sceptical of enhancers and express greater concerns. Four themes were identified in the thematic analysis: (1) risk, (2) morality, (3) enhancer effects, and (4) regulation. To increase acceptance and perceived legitimacy in decision-making, it is recommended that regulators engage a variety of stakeholders in transparent decision-making processes when forming tournament rules and regulations. This will help address the fragmented regulatory landscape and prevent potential differences in the perception of tournament winners based on the governing body supervising the competition.
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Affiliation(s)
- Maximilian A. Friehs
- Psychology of Conflict Risk and Safety, University of Twente, Enschede, Netherlands
- School of Psychology, University College Dublin, Dublin, Ireland
- Max-Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Madison Klarkowski
- Human-Computer Interaction Lab, Department of Computer Science, University of Saskatchewan, Leipzig, Germany
| | - Julian Frommel
- Interaction Media Group, Information and Computing Sciences, Utrecht University, Utrecht, Netherlands
| | - Cody Phillips
- Human-Computer Interaction Lab, Department of Computer Science, University of Saskatchewan, Leipzig, Germany
| | - Regan L. Mandryk
- Faculty of Computer Science, University of Victoria, Victoria, BC, Canada
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Kim J, Kim HW, Kovar J, Lee YS. Neural consequences of binaural beat stimulation on auditory sentence comprehension: an EEG study. Cereb Cortex 2024; 34:bhad459. [PMID: 38044462 DOI: 10.1093/cercor/bhad459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 11/05/2023] [Accepted: 11/06/2023] [Indexed: 12/05/2023] Open
Abstract
A growing literature has shown that binaural beat (BB)-generated by dichotic presentation of slightly mismatched pure tones-improves cognition. We recently found that BB stimulation of either beta (18 Hz) or gamma (40 Hz) frequencies enhanced auditory sentence comprehension. Here, we used electroencephalography (EEG) to characterize neural oscillations pertaining to the enhanced linguistic operations following BB stimulation. Sixty healthy young adults were randomly assigned to one of three listening groups: 18-Hz BB, 40-Hz BB, or pure-tone baseline, all embedded in music. After listening to the sound for 10 min (stimulation phase), participants underwent an auditory sentence comprehension task involving spoken sentences that contained either an object or subject relative clause (task phase). During the stimulation phase, 18-Hz BB yielded increased EEG power in a beta frequency range, while 40-Hz BB did not. During the task phase, only the 18-Hz BB resulted in significantly higher accuracy and faster response times compared with the baseline, especially on syntactically more complex object-relative sentences. The behavioral improvement by 18-Hz BB was accompanied by attenuated beta power difference between object- and subject-relative sentences. Altogether, our findings demonstrate beta oscillations as a neural correlate of improved syntactic operation following BB stimulation.
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Affiliation(s)
- Jeahong Kim
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX 75080, United States
- Callier Clinical Research Center, The University of Texas at Dallas, Richardson, TX 75080, United States
| | - Hyun-Woong Kim
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX 75080, United States
- Callier Clinical Research Center, The University of Texas at Dallas, Richardson, TX 75080, United States
- Center for BrainHealth, The University of Texas at Dallas, Dallas, TX 75235, United States
- Department of Psychology, The University of Texas at Dallas, Richardson, TX 75080, United States
| | - Jessica Kovar
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX 75080, United States
- Callier Clinical Research Center, The University of Texas at Dallas, Richardson, TX 75080, United States
| | - Yune Sang Lee
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX 75080, United States
- Callier Clinical Research Center, The University of Texas at Dallas, Richardson, TX 75080, United States
- Center for BrainHealth, The University of Texas at Dallas, Dallas, TX 75235, United States
- Department of Speech, Language, and Hearing, The University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX 75080, United States
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Wilkerson GB, Fleming LR, Adams VP, Petty RJ, Carlson LM, Hogg JA, Acocello SN. Assessment and Training of Perceptual-Motor Function: Performance of College Wrestlers Associated with History of Concussion. Brain Sci 2024; 14:68. [PMID: 38248283 PMCID: PMC10813796 DOI: 10.3390/brainsci14010068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/01/2023] [Accepted: 01/08/2024] [Indexed: 01/23/2024] Open
Abstract
Concussion may affect sport performance capabilities related to the visual perception of environmental events, rapid decision-making, and the generation of effective movement responses. Immersive virtual reality (VR) offers a means to quantify, and potentially enhance, the speed, accuracy, and consistency of responses generated by integrated neural processes. A cohort of 24 NCAA Division I male wrestlers completed VR assessments before and after a 3-week VR training program designed to improve their perceptual-motor performance. Prior to training, the intra-individual variability (IIV) among 40 successive task trials for perceptual latency (i.e., time elapsed between visual stimulus presentation and the initiation of movement response) demonstrated strong discrimination between 10 wrestlers who self-reported a history of concussion from 14 wrestlers who denied ever having sustained a concussion (Area Under Curve ≥ 0.750 for neck, arm, and step movements). Natural log transformation improved the distribution normality of the IIV values for both perceptual latency and response time (i.e., time elapsed between visual stimulus presentation and the completion of movement response). The repeated measures ANOVA results demonstrated statistically significant (p < 0.05) pre- and post-training differences between groups for the IIV in perceptual latency and the IIV in response time for neck, arm, and step movements. Five of the six IIV metrics demonstrated a statistically significant magnitude of change for both groups, with large effect sizes. We conclude that a VR assessment can detect impairments in perceptual-motor performance among college wrestlers with a history of concussion. Although significant post-training group differences were evident, VR training can yield significant performance improvements in both groups.
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Affiliation(s)
- Gary B. Wilkerson
- Department of Health & Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN 37403, USA; (L.M.C.); (J.A.H.); (S.N.A.)
| | - Lexi R. Fleming
- Department of Intercollegiate Athletics, Lincoln Memorial University, Harrogate, TN 37752, USA;
| | - Victoria P. Adams
- Sports Medicine Outreach Program, Piedmont Physicians Athens Regional Medical Center, Watkinsville, GA 30677, USA;
| | - Richard J. Petty
- Department of Intercollegiate Athletics, University of Tennessee at Chattanooga, Chattanooga, TN 37403, USA;
| | - Lynette M. Carlson
- Department of Health & Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN 37403, USA; (L.M.C.); (J.A.H.); (S.N.A.)
| | - Jennifer A. Hogg
- Department of Health & Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN 37403, USA; (L.M.C.); (J.A.H.); (S.N.A.)
| | - Shellie N. Acocello
- Department of Health & Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN 37403, USA; (L.M.C.); (J.A.H.); (S.N.A.)
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Nagai T, Schilaty ND, Wong H, Keller VC, Stiennon ST, Chang RW, Stuart MJ, Krause DA. Acute effects of an isometric neck warm-up programme on neck performance characteristics and ultrasound-based morphology. Ann Med 2023; 55:2295402. [PMID: 38142049 PMCID: PMC10763903 DOI: 10.1080/07853890.2023.2295402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/11/2023] [Indexed: 12/25/2023] Open
Abstract
OBJECTIVE Athletic performance can be enhanced immediately after an isometric warm-up, a phenomenon termed post-activation performance enhancement (PAPE). While isometric warm-ups can improve lower extremity sprint and jump performance, neck-specific isometric warm-ups need development and validation for mild traumatic brain disorders and neck pain. This study examined acute effects of isometric warm-ups on neck performance and morphology. METHODS Arm 1: Twenty-six adults (13 M:13F) completed neck performance testing before and after a 10-minute neck isometric warm-up or stationary bike (sham) between two visits. Testing included visual-motor reaction time, peak force, rate of force development, force steadiness, and force replication/proprioception measured by a 6-axis load cell. An inclinometer assessed range-of-motion. Paired t-tests and two-way ANOVA examined effects of neck/bike warm-up and interaction effects, respectively. Arm 2: 24 adults (11 M:13F) completed ultrasound scans of cervical muscles: before 20-minute rest (sham), and before/after a 5-min neck isometric warm-up. Longus colli cross-sectional area and sternocleidomastoid/upper trapezius thickness and stiffness, and cervical extensors thickness was assessed. One-way ANOVA compared morphological values at sham, before, and after warm-up. Significance was set at p < 0.05. RESULTS Isometric neck warm-up increased rate of force development in flexion (p = 0.022), extension (p = 0.001-0.003), right lateral flexion (p = 0.004-0.032), left lateral flexion (p = 0.005-0.014), while peak force improved only in left lateral flexion (p = 0.032). Lateral flexion range-of-motion increased after neck warm-up (p = 0.003-0.026). Similarly, longus colli cross-sectional area (p = 0.016) and sternocleidomastoid thickness (p = 0.004) increased. CONCLUSIONS Increased neck performance characteristics and morphology are likely due to PAPE effects of isometric neck warm-up. For coaches and athletes, simple isometric contractions could be added to existing warm-ups to reduce prevalence, incidence, and severity of mild traumatic brain injuries and neck pain.
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Affiliation(s)
- Takashi Nagai
- United States Army Research Institute and Environmental Medicine, Natick, MA, USA
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Nathan D. Schilaty
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
- Department of Neurosurgery and Brain Repair, University of South FL, Tampa, FL, USA
- Department of Medical Engineering, University of South Florida, Tampa, FL, USA
- Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA
| | - Hanwen Wong
- Department of Physical Medicine & Rehabilitation, Mayo Clinic, Rochester, MN, USA
| | - Valerie C. Keller
- Department of Physical Medicine & Rehabilitation, Mayo Clinic, Rochester, MN, USA
| | - Sean T. Stiennon
- Department of Physical Medicine & Rehabilitation, Mayo Clinic, Rochester, MN, USA
| | - Ryan W.B Chang
- Department of Physical Medicine & Rehabilitation, Mayo Clinic, Rochester, MN, USA
| | | | - David A. Krause
- Department of Physical Medicine & Rehabilitation, Mayo Clinic, Rochester, MN, USA
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McGrath JW, Neville J, Stewart T, Lamb M, Alway P, King M, Cronin J. Can an inertial measurement unit, combined with machine learning, accurately measure ground reaction forces in cricket fast bowling? Sports Biomech 2023:1-13. [PMID: 37941397 DOI: 10.1080/14763141.2023.2275251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 01/17/2023] [Indexed: 11/10/2023]
Abstract
This study examined whether an inertial measurement unit (IMU) could measure ground reaction force (GRF) during a cricket fast bowling delivery. Eighteen male fast bowlers had IMUs attached to their upper back and bowling wrist. Each participant bowled 36 deliveries, split into three different intensity zones: low = 70% of maximum perceived bowling effort, medium = 85%, and high = 100%. A force plate was embedded into the bowling crease to measure the ground truth GRF. Three machine learning models were used to estimate GRF from the IMU data. The best results from all models showed a mean absolute percentage error of 22.1% body weights (BW) for vertical and horizontal peak force, 24.1% for vertical impulse, 32.6% and 33.6% for vertical and horizontal loading rates, respectively. The linear support vector machine model had the most consistent results. Although results were similar to other papers that have estimated GRF, the error would likely prevent its use in individual monitoring. However, due to the large differences in raw GRFs between participants, researchers may be able to help identify links among GRF, injury, and performance by categorising values into levels (i.e., low and high).
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Affiliation(s)
- Joseph W McGrath
- Sports Performance Research Institute New Zealand, AUT University, Auckland, New Zealand
- Manukau Institute of Technology School of Sport, Auckland, New Zealand
- Paramedicine and Emergency Management, School of Health Care Practice, AUT University, Auckland, New Zealand
| | - Jonathon Neville
- Sports Performance Research Institute New Zealand, AUT University, Auckland, New Zealand
| | - Tom Stewart
- Sports Performance Research Institute New Zealand, AUT University, Auckland, New Zealand
- Human Potential Centre, AUT University, Auckland, New Zealand
| | - Matt Lamb
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Peter Alway
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- England & Wales Cricket Board
| | - Mark King
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - John Cronin
- Sports Performance Research Institute New Zealand, AUT University, Auckland, New Zealand
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Walcott G, Hickling FW, Charles CAD. To Di World: Jamaican soccer, poiesis and post-colonial transformation. Transcult Psychiatry 2023; 60:835-843. [PMID: 37904537 DOI: 10.1177/13634615231198005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
This article presents a case study of an innovative culturally based therapeutic approach using collective poiesis to improve the functioning of a youth sports team in Jamaica. In recent decades, Jamaica has endured high levels of violence and corruption, and has been ranked among the top four countries in the world in terms of murder rate per capita. We conjecture that a high prevalence of personality disorder linked to the legacy of slavery and colonialism often impedes Jamaicans from achieving success in diverse fields, including sports. Psychological interventions in the preparation of football teams are a novelty, and have been used mainly to enhance global team performance or individual player skill. The use of psychological interventions to address personality disorder psychopathology on the soccer pitch has not been reported. Psychohistoriographic cultural therapy (PCT) integrates psychological perspectives with a dialectic method of historical analysis and uses collective poiesis as a vehicle to translate insights through an embodied cognitive restructuring process. Two workshops were carried out with a high school football team using PCT techniques. The process of dialectic reasoning engaged their collective ideas and insights to establish a psychic centrality that was expressed in poetic form to illustrate the pathologies of the group in an emotionally safe and psychologically acceptable narrative. This poetic narrative of the group's psychic centrality counters the personality disorder psychopathology caused by the lingering intergenerational wounds of slavery, colonial oppression and collective trauma.
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Omidian H, Chowdhury SD. High-Performing Conductive Hydrogels for Wearable Applications. Gels 2023; 9:549. [PMID: 37504428 PMCID: PMC10379850 DOI: 10.3390/gels9070549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/04/2023] [Accepted: 07/04/2023] [Indexed: 07/29/2023] Open
Abstract
Conductive hydrogels have gained significant attention for their extensive applications in healthcare monitoring, wearable sensors, electronic devices, soft robotics, energy storage, and human-machine interfaces. To address the limitations of conductive hydrogels, researchers are focused on enhancing properties such as sensitivity, mechanical strength, electrical performance at low temperatures, stability, antibacterial properties, and conductivity. Composite materials, including nanoparticles, nanowires, polymers, and ionic liquids, are incorporated to improve the conductivity and mechanical strength. Biocompatibility and biosafety are emphasized for safe integration with biological tissues. Conductive hydrogels exhibit unique properties such as stretchability, self-healing, wet adhesion, anti-freezing, transparency, UV-shielding, and adjustable mechanical properties, making them suitable for specific applications. Researchers aim to develop multifunctional hydrogels with antibacterial characteristics, self-healing capabilities, transparency, UV-shielding, gas-sensing, and strain-sensitivity.
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Affiliation(s)
- Hossein Omidian
- Barry and Judy Silverman College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL 33328, USA
| | - Sumana Dey Chowdhury
- Barry and Judy Silverman College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL 33328, USA
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Meier N, Schlie J, Schmidt A. CrossFit ®: 'Unknowable' or Predictable?-A Systematic Review on Predictors of CrossFit ® Performance. Sports (Basel) 2023; 11:112. [PMID: 37368562 DOI: 10.3390/sports11060112] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/26/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
The functional fitness training program CrossFit® is experiencing fast-growing and widespread popularity with day-to-day varying 'Workouts of the Day' (WOD). Even among tactical athletes, the training program is widely applied. Nevertheless, there is a lack of data on which parameters influence CrossFit® performance. For this reason, the purpose of this study is to conduct a systematic review of the existing literature to identify and summarize predictors of CrossFit® performance and performance enhancement. In accordance with the PRISMA guidelines, a systematic search of the following databases was conducted in April 2022: PubMed, SPORTDiscus, Scopus, and Web of Science. Using the keyword 'CrossFit', 1264 entries are found, and 21 articles are included based on the eligibility criteria. In summary, the studies show conflicting results, and no specific key parameter was found that predicts CrossFit® performance regardless of the type of WOD. In detail, the findings indicate that physiological parameters (in particular, body composition) and high-level competitive experience have a more consistent influence than specific performance variables. Nevertheless, in one-third of the studies, high total body strength (i.e., CrossFit® Total performance) and trunk strength (i.e., back squat performance) correlate with higher workout scores. For the first time, this review presents a summary of performance determinants in CrossFit®. From this, a guiding principle for training strategies may be derived, suggesting that a focus on body composition, body strength, and competition experience may be recommended for CrossFit® performance prediction and performance enhancement.
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Affiliation(s)
- Nicole Meier
- Institut für Sportwissenschaft, Fakultät für Humanwissenschaften, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany
| | - Jennifer Schlie
- Institut für Sportwissenschaft, Fakultät für Humanwissenschaften, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany
| | - Annette Schmidt
- Institut für Sportwissenschaft, Fakultät für Humanwissenschaften, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany
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King DG, Stride E, Mendis J, Gurton WH, Macrae H, Jones L, Hunt J. A Double-Blind, Randomized, Placebo-Controlled Pilot Study examining an Oxygen Nanobubble Beverage for 16.1-km Time Trial and Repeated Sprint Cycling Performance. J Diet Suppl 2023; 21:167-181. [PMID: 37127913 DOI: 10.1080/19390211.2023.2203738] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
There is growing interest of ergogenic aids that deliver supplemental oxygen during exercise and recovery, however, breathing supplemental oxygen via specialist facemasks is often not feasible. Therefore, this study investigated the effect of an oxygen-nanobubble beverage during submaximal and repeated sprint cycling. In a double-blind, randomized, placebo-controlled study, 10 male cyclists (peak aerobic capacity, 56.9 ± 6.1 mL·kg-1·min-1; maximal aerobic power, 385 ± 25 W) completed submaximal or maximal exercise after consuming an oxygen-nanobubble (O2) or placebo (PLA) beverage. Submaximal trials comprised 30-min of steady-state cycling at 60% peak aerobic capacity and 16.1-km time-trial (TT). Maximal trials involved 4 × 30 s Wingate tests interspersed by 4-min recovery. Time-to-completion during the 16.1-km TT was 2.4% faster after O2 compared with PLA (95% CI = 0.7-4.0%, p = 0.010, d = 0.41). Average power for the 16.1-km TT was 4.1% higher for O2 vs. PLA (95% CI = 2.1-7.3%, p = 0.006, d = 0.28). Average peak power during the repeated Wingate tests increased by 7.1% for O2 compared with PLA (p = 0.002, d = 0.58). An oxygen-nanobubble beverage improves performance during submaximal and repeated sprint cycling, therefore may provide a practical and effective ergogenic aid for competitive cyclists.
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Affiliation(s)
- David G King
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Eleanor Stride
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Jeewaka Mendis
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - William H Gurton
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Heather Macrae
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Louise Jones
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Julie Hunt
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
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Mølmen KS, Rønnestad BR. A narrative review exploring advances in interval training for endurance athletes. Appl Physiol Nutr Metab 2023. [PMID: 38564798 DOI: 10.1139/apnm-2023-0603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Interval training is considered an essential training component in endurance athletes. Recently, there has been a focus on optimization of interval training characteristics to sustain a high fraction of maximal oxygen consumption (≥90% VO2max) to improve physiological adaptations and performance. Herein, we present a synopsis of the latest research exploring both acute and chronic studies in endurance athletes. Further, a decision flowchart was created for athletes and coaches to select the most appropriate interval training regime for specific individualized goals.
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Affiliation(s)
- Knut Sindre Mølmen
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Bent R Rønnestad
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
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13
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Guo RT, Wang J, Bi ZX, Chen X, Hu X, Pan WG. Recent Advances and Perspectives of Core-Shell Nanostructured Materials for Photocatalytic CO 2 Reduction. Small 2023; 19:e2206314. [PMID: 36515282 DOI: 10.1002/smll.202206314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/14/2022] [Indexed: 06/17/2023]
Abstract
Photocatalytic CO2 conversion into solar fuels is a promising technology to alleviate CO2 emissions and energy crises. The development of core-shell structured photocatalysts brings many benefits to the photocatalytic CO2 reduction process, such as high conversion efficiency, sufficient product selectivity, and endurable catalyst stability. Core-shell nanostructured materials with excellent physicochemical features take an irreplaceable position in the field of photocatalytic CO2 reduction. In this review, the recent development of core-shell materials applied for photocatalytic reduction of CO2 is introduced . First, the basic principle of photocatalytic CO2 reduction is introduced. In detail, the classification and synthesis techniques of core-shell catalysts are discussed. Furthermore, it is also emphasized that the excellent properties of the core-shell structure can greatly improve the activity, selectivity, and stability in the process of photocatalytic CO2 reduction. Hopefully, this paper can provide a favorable reference for the preparation of efficient photocatalysts for CO2 reduction.
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Affiliation(s)
- Rui-Tang Guo
- College of Energy and Mechanical Engineering, Shanghai University of Electric Power, No. 2588 Changyang Road, Shanghai, 200090, China
- Shanghai Engineering Research Center of Power Generation Environment Protection, Shanghai, China
| | - Juan Wang
- College of Energy and Mechanical Engineering, Shanghai University of Electric Power, No. 2588 Changyang Road, Shanghai, 200090, China
| | - Zhe-Xu Bi
- College of Energy and Mechanical Engineering, Shanghai University of Electric Power, No. 2588 Changyang Road, Shanghai, 200090, China
| | - Xin Chen
- College of Energy and Mechanical Engineering, Shanghai University of Electric Power, No. 2588 Changyang Road, Shanghai, 200090, China
| | - Xing Hu
- College of Energy and Mechanical Engineering, Shanghai University of Electric Power, No. 2588 Changyang Road, Shanghai, 200090, China
| | - Wei-Guo Pan
- College of Energy and Mechanical Engineering, Shanghai University of Electric Power, No. 2588 Changyang Road, Shanghai, 200090, China
- Shanghai Engineering Research Center of Power Generation Environment Protection, Shanghai, China
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14
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Cho JY, Lee S, Jang WK. Performance-Enhanced Static Modulated Fourier Transform Spectrometer with a Spectral Reconstruction. Sensors (Basel) 2023; 23:s23052603. [PMID: 36904807 PMCID: PMC10007488 DOI: 10.3390/s23052603] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/20/2023] [Accepted: 02/23/2023] [Indexed: 06/12/2023]
Abstract
A static modulated Fourier transform spectrometer has been noted to be a compact and fast evaluation tool for spectroscopic inspection, and many novel structures have been reported to support its performance. However, it still suffers from poor spectral resolution due to the limited sampling data points, which marks its intrinsic drawback. In this paper, we outline the enhanced performance of a static modulated Fourier transform spectrometer with a spectral reconstruction method that can compensate for the insufficient data points. An enhanced spectrum can be reconstructed by applying a linear regression method to a measured interferogram. We obtain the transfer function of a spectrometer by analyzing what interferogram can be detected with different values of parameters such as focal length of the Fourier lens, mirror displacement, and wavenumber range, instead of direct measurement of the transfer function. Additionally, the optimal experimental conditions for the narrowest spectral width are investigated. Application of the spectral reconstruction method achieves an improved spectral resolution from 74 cm-1 when spectral reconstruction is not applied to 8.9 cm-1, and a narrowed spectral width from 414 cm-1 to 371 cm-1, which are close to the values of the spectral reference. In conclusion, the spectral reconstruction method in a compact static modulated Fourier transform spectrometer effectively enhances its performance without any additional optic in the structure.
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Affiliation(s)
- Ju Yong Cho
- Department of Aeronautic Electricity, Hanseo University, 46, Hanseo 1-ro, Seosan-si 31962, Republic of Korea
| | - Seunghoon Lee
- Satellite Research Directorate, Korea Aerospace Research Institute, 169-82, Gwahak-ro, Daejeon 34133, Republic of Korea
| | - Won Kweon Jang
- Department of Aeronautic Electricity, Hanseo University, 46, Hanseo 1-ro, Seosan-si 31962, Republic of Korea
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15
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Nyawose S, Naidoo R, Naumovski N, McKune AJ. Dietary supplements and beverages: Knowledge, attitudes, and practices among semi-professional soccer players in KwaZulu-Natal, South Africa. S Afr J Sports Med 2023; 34:v34i1a14018. [PMID: 36815933 PMCID: PMC9924549 DOI: 10.17159/2078-516x/2022/v34i1a14018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Background The ingestion of dietary supplements and beverages is prevalent in soccer, at the amateur and professional level. The absence of professional advice at non-professional level makes amateur soccer players susceptible to ingesting unsafe supplements. Objectives To determine the knowledge, attitudes and practices of ABC Motsepe League (semi-professional) players in KwaZulu-Natal regarding the use of dietary supplements and beverages. Methods Three hundred and forty-three soccer players participated in a cross-sectional study. Knowledge, attitudes and practices were determined using a questionnaire. Researchers visited twelve teams. On the day of the visit to each team, information sheets and questionnaires were given to participants. Questionnaires were collected immediately following completion. Descriptive statistics were used, including means and standard deviations, where applicable. Inferential statistics, Chi-square and binomial tests were used to analyse the results. Statistical significance was set at p < 0.05. Results Sports beverages were the most recommended and commonly used, followed by energy beverages. Dietary supplements were the least-known used. Participants used beverages and dietary supplements to assist in providing more energy (67%), improve health (65%) and improve performance (55%) (p<0.001). Seventy-three percent of participants lacked knowledge about the anti-doping policy (p<0.001), with 87% having never attended a workshop on the safe use of supplements and beverages, or anti-doping awareness campaigns (p<0.001). Thirty-eight percent had not heard of the South African Institute for Drug-Free Sport (SAIDS), and 84% were not familiar with the yearly updated World Anti-Doping Agency's (WADA) prohibited list (p<0.001). Of the 59% who did not take dietary supplements or beverages, 75% had insufficient information regarding them (p<0.001), 66% indicated that dietary supplements and beverages were costly (p=0.001), and 55% indicated they did not need dietary supplements and beverages (p=0.32). Conclusion There is a need for an educational programme on the safe use of dietary supplements, and sports and energy beverages among KwaZulu-Natal semi-professional soccer players.
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Affiliation(s)
- S Nyawose
- Discipline of Biokinetics, Exercise, and Leisure Sciences. School of Health Sciences, University of KwaZulu-Natal, Durban,
South Africa
| | - R Naidoo
- Discipline of Biokinetics, Exercise, and Leisure Sciences. School of Health Sciences, University of KwaZulu-Natal, Durban,
South Africa
| | - N Naumovski
- Faculty of Health, University of Canberra, Discipline of Nutrition and Dietetics, University of Canberra, Canberra, ACT,
Australia,Functional Foods and Nutrition Research (FFNR) Laboratory, University of Canberra, Ngunnawal Country, ACT,
Australia,Department of Nutrition and Dietetics, Harokopio University, Athens 17671,
Greece
| | - AJ McKune
- Discipline of Biokinetics, Exercise, and Leisure Sciences. School of Health Sciences, University of KwaZulu-Natal, Durban,
South Africa,Functional Foods and Nutrition Research (FFNR) Laboratory, University of Canberra, Ngunnawal Country, ACT,
Australia,Faculty of Health, Discipline of Sport and Exercise Science, University of Canberra, Canberra, ACT,
Australia,Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT,
Australia
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16
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Salem MS, Zekry A, Abouelatta M, Shaker A, Salem MS, Gontrand C, Saeed A. Boosting the Electrostatic MEMS Converter Output Power by Applying Three Effective Performance-Enhancing Techniques. Micromachines (Basel) 2023; 14:485. [PMID: 36838185 PMCID: PMC9964943 DOI: 10.3390/mi14020485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/05/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
This current study aims to enhance the electrostatic MEMS converter performance mainly by boosting its output power. Three different techniques are applied to accomplish such performance enhancement. Firstly, the power is boosted by scaling up the technology of the converter CMOS accompanied circuit, the power conditioning, and power controlling circuits, from 0.35 µm to 0.6 µm CMOS technology. As the converter area is in the range of mm2, there are no restrictions concerning the scaling up of the accompanied converter CMOS circuits. As a result, the maximum voltage of the system for harvesting energy, Vmax, which is the most effective system constraint that greatly affects the converter's output power, increases from 8 V to 30 V. The output power of the designed and simulated converter based on the 0.6 µm technology increases from 2.1 mW to 4.5 mW. Secondly, the converter power increases by optimizing its technological parameters, the converter thickness and the converter finger width and length. Such optimization causes the converter output power to increase from 4.5 mW to 11.2 mW. Finally, the converter structure is optimized to maximize its finger length by using its wasted shuttle mass area which does not contribute to its capacitances and output power. The proposed structure increases the converter output power from 11.2 mW to 14.29 mW. Thus, the three applied performance enhancement techniques boosted the converter output power by 12.19 mW, which is a considerable enhancement in the converter performance. All simulations are carried out using COMSOL Multiphysics 5.4.
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Affiliation(s)
- Mona S. Salem
- Electronics and Communications Engineering Department, Faculty of Engineering, Ain Shams University (ASU), Cairo 11566, Egypt
| | - Abdelhalim Zekry
- Electronics and Communications Engineering Department, Faculty of Engineering, Ain Shams University (ASU), Cairo 11566, Egypt
| | - Mohamed Abouelatta
- Electronics and Communications Engineering Department, Faculty of Engineering, Ain Shams University (ASU), Cairo 11566, Egypt
| | - Ahmed Shaker
- Physics and Mathematics Engineering Department, Faculty of Engineering, Ain Shams University (ASU), Cairo 11566, Egypt
| | - Marwa S. Salem
- Department of Computer Engineering, Computer Science and Engineering College, University of Ha’il, Ha’il 55211, Saudi Arabia
| | - Christian Gontrand
- National Institute of Applied Sciences of Lyon (INSA Lyon), 69621 Lyon, France
- IEP, INSA—Fès, Université Euro-Méditerranéenne de Fès, Fès 30120, Morocco
| | - Ahmed Saeed
- Electrical Engineering Department, Faculty of Engineering and Technology, Future University in Egypt, New Cairo 11835, Egypt
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17
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Zhang HJ, Liu YF, Zheng X, Feng J. Improved Performance of All-Inorganic Perovskite Light-emitting Diodes via Nanostructured Stamp Imprinting. Chemphyschem 2023; 24:e202200860. [PMID: 36782095 DOI: 10.1002/cphc.202200860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 01/23/2023] [Indexed: 02/15/2023]
Abstract
Halide perovskites are emerging emitters with excellent optoelectronic properties. Contrary to the large grain fabrication goal in perovskite solar cells, perovskite light-emitting diodes (PeLEDs) based on small grain enable efficient radiative recombination because of relatively higher charge carrier densities due to spatial confinement. However, achieving small-sized grain growth with superior crystal quality and film morphology remains a challenge. In this work, we demonstrated a nanostructured stamp thermal imprinting strategy to boost the surface coverage and improve the crystalline quality of CsPbBr3 film, particularly confine the grain size, leading to the improvement of luminance and efficiency of PeLEDs. We improved the thermal imprinting process utilizing the nanostructured stamp to selectively manipulate the nucleation and growth in the nanoscale region and acquire small-sized grain accompanied by improved crystal quality and surface morphology of the film. By optimizing the imprinting pressure and the period of the nanostructures, appropriate grain size, high surface coverage, small surface roughness and improved crystallization could be achieved synchronously. Finally, the maximum luminance and efficiency of PeLEDs achieved by nanostructured stamp imprinting with a period of 320 nm are 67600 cd/m2 and 16.36 cd/A, respectively. This corresponds to improvements of 123 % in luminance and 100 % in efficiency, compared to that of PeLEDs without the imprinting.
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Affiliation(s)
- Hai-Jing Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, China
| | - Yue-Feng Liu
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, China
| | - Xin Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, China
| | - Jing Feng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, China
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18
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Petróczi A, Cruyff M, de Hon O, Sagoe D, Saugy M. Corrigendum: Hidden figures: Revisiting doping prevalence estimates previously reported for two major international sport events in the context of further empirical evidence and the extant literature. Front Sports Act Living 2023; 5:1129320. [PMID: 36798089 PMCID: PMC9928175 DOI: 10.3389/fspor.2023.1129320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 01/03/2023] [Indexed: 02/01/2023] Open
Abstract
[This corrects the article DOI: 10.3389/fspor.2022.1017329.].
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Affiliation(s)
- Andrea Petróczi
- School of Life Sciences, Pharmacy and Chemistry, Faculty of Health, Science, Social Care and Education, Kingston University, London, United Kingdom,Department of Movement Sciences, Faculty of Movement and Rehabilitation Sciences, Katholieke Universiteit (KU) Leuven, Leuven, Belgium,Willibald Gebhardt Research Institute, University of Münster, Münster, Germany,Correspondence: Andrea Petróczi
| | - Maarten Cruyff
- Faculty of Social Sciences, Utrecht University, Utrecht, Netherlands
| | - Olivier de Hon
- Doping Authority Netherlands, Capelle aan den IJssel, Netherlands
| | - Dominic Sagoe
- Department of Psychosocial Science, University of Bergen, Bergen, Norway
| | - Martial Saugy
- Research and Expertise in anti-Doping Sciences (REDs), Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
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19
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Wang Y, Cao X, Wang N. Recent Progress in Piezoelectric-Triboelectric Effects Coupled Nanogenerators. Nanomaterials (Basel) 2023; 13:nano13030385. [PMID: 36770350 PMCID: PMC9921494 DOI: 10.3390/nano13030385] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/14/2023] [Accepted: 01/16/2023] [Indexed: 06/01/2023]
Abstract
Piezoelectric and triboelectric nanogenerators have been widely studied in the past years for their advantages of easy design/manufacturing, small size, and flexibility. Nanogenerators that are developed based on the coupled piezoelectric and triboelectric effects (PTCNG) can make full use of the mechanical energies and achieve both higher output and sensing performance. This review aims to cover the recent research progress of PTCNG by presenting in detail their key technologies in terms of operating principles, integration concept, and performance enhancement strategies, with a focus on their structural simplification and efficiency performance improvement. The latest applications of PTCNG in tactile sensors and energy-harvesting system are also illustrated. Finally, we discuss the main challenges and prospects for the future development of PTCNG, hoping that this work can provide a new insight into the development of all-in-one mechanical energy-scavenging and sensing devices.
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Affiliation(s)
- Yifei Wang
- Center for Green Innovation, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Xia Cao
- Center for Green Innovation, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Ning Wang
- Center for Green Innovation, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
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20
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Salagas A, Tsoukos A, Terzis G, Paschalis V, Katsikas C, Krzysztofik M, Wilk M, Zajac A, Bogdanis GC. Effectiveness of either short-duration ischemic pre-conditioning, single-set high-resistance exercise, or their combination in potentiating bench press exercise performance. Front Physiol 2022; 13:1083299. [PMID: 36589445 PMCID: PMC9797974 DOI: 10.3389/fphys.2022.1083299] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 12/03/2022] [Indexed: 12/23/2022] Open
Abstract
This study compared the effects of short-duration ischemic preconditioning, a single-set high-resistance exercise and their combination on subsequent bench press performance. Twelve men (age: 25.8 ± 6.0 years, bench press 1-RM: 1.21 ± 0.17 kg kg-1 body mass) performed four 12 s sets as fast as possible, with 2 min of recovery between sets, against 60% 1-RM, after: a) 5 min ischemic preconditioning (IPC; at 100% of full arterial occlusion pressure), b) one set of three bench press repetitions at 90% 1-RM (PAPE), c) their combination (PAPE + IPC) or d) control (CTRL). Mean barbell velocity in ischemic preconditioning was higher than CTRL (by 6.6-9.0%, p < 0.05) from set 1 to set 3, and higher than PAPE in set 1 (by 4.4%, p < 0.05). Mean barbell velocity in PAPE was higher than CTRL from set 2 to set 4 (by 6.7-8.9%, p < 0.05), while mean barbell velocity in PAPE + IPC was higher than CTRL only in set 1 (+5.8 ± 10.0%). Peak barbell velocity in ischemic preconditioning and PAPE was higher than CTRL (by 7.8% and 8.5%, respectively; p < 0.05). Total number of repetitions was similarly increased in all experimental conditions compared with CTRL (by 7.0-7.9%, p < 0.05). Rating of perceived exertion was lower in ischemic preconditioning compared with CTRL (p < 0.001) and PAPE (p = 0.045), respectively. These results highlight the effectiveness of short-duration ischemic preconditioning in increasing bench press performance, and suggest that it may be readily used by strength and conditioning coaches during resistance training due to its brevity and lower perceived exertion.
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Affiliation(s)
- Andreas Salagas
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Athanasios Tsoukos
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Gerasimos Terzis
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Vassilis Paschalis
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Christos Katsikas
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Michal Krzysztofik
- Institute of Sport Sciences, Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Michal Wilk
- Institute of Sport Sciences, Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Adam Zajac
- Institute of Sport Sciences, Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Gregory C. Bogdanis
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece,*Correspondence: Gregory C. Bogdanis,
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21
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Brocherie F, Timon R. Editorial: Long-term effects of hypoxic conditioning on sports performance, health and well-being. Front Physiol 2022; 13:1112754. [PMID: 36569755 PMCID: PMC9782396 DOI: 10.3389/fphys.2022.1112754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022] Open
Affiliation(s)
- Franck Brocherie
- Laboratory Sport, Expertise and Performance (EA 7370), French Institute of Sport, Paris, France,*Correspondence: Franck Brocherie,
| | - Rafael Timon
- Faculty of Sports Sciences, University of Extremadura, Caceres, Spain
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22
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Petróczi A, Cruyff M, de Hon O, Sagoe D, Saugy M. Hidden figures: Revisiting doping prevalence estimates previously reported for two major international sport events in the context of further empirical evidence and the extant literature. Front Sports Act Living 2022; 4:1017329. [PMID: 36544544 PMCID: PMC9760848 DOI: 10.3389/fspor.2022.1017329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 10/25/2022] [Indexed: 12/12/2022] Open
Abstract
Background High levels of admitted doping use (43.6% and 57.1%) were reported for two international sport events in 2011. Because these are frequently referenced in evaluating aspects of anti-doping, having high level of confidence in these estimates is paramount. Objectives In this study, we present new prevalence estimates from a concurrently administered method, the Single Sample Count (SSC), and critically review the two sets of estimates in the context of other doping prevalence estimates. Methods The survey featuring the SSC model was completed by 1,203 athletes at the 2011 World Championships in Athletics (WCA) (65.3% of all participating athletes) and 954 athletes at the 2011 Pan-Arab Games (PAG) (28.2% of all participating athletes). At WCA, athletes completed both UQM and SSC surveys in randomised order. At PAG, athletes were randomly allocated to one of the two surveys. Doping was defined as "having knowingly violated anti-doping regulations by using a prohibited substance or method." Results Estimates with the SSC model for 12-month doping prevalence were 21.2% (95% CI: 9.69-32.7) at WCA and 10.6% (95% CI: 1.76-19.4) at PAG. Estimated herbal, mineral, and/or vitamin supplements use was 8.57% (95% CI: 1.3-16.11) at PAG. Reliability of the estimates were confirmed with re-sampling method (n = 1,000, 80% of the sample). Survey non-compliance (31.90%, 95%CI: 26.28-37.52; p < 0.0001) was detected in the WCA data but occurred to a lesser degree at PAG (9.85%, 95% CI: 4.01-15.69, p = 0.0144 and 11.43%, 95% CI: 5.31-11.55, p = 0.0196, for doping and nutritional supplement use, respectively). A large discrepancy between those previously reported from the UQM and the prevalence rate estimated by the SSC model for the same population is evident. Conclusion Caution in interpreting these estimates as bona fide prevalence rates is warranted. Critical appraisal of the obtained prevalence rates and triangulation with other sources are recommended over "the higher rate must be closer to the truth" heuristics. Non-compliance appears to be the Achilles heel of the indirect estimation models thus it should be routinely tested for and minimised. Further research into cognitive and behaviour aspects, including motivation for honesty, is needed to improve the ecological validity of the estimated prevalence rates.
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Affiliation(s)
- Andrea Petróczi
- School of Life Sciences, Pharmacy and Chemistry, Faculty of Health, Science, Social Care and Education, Kingston University, London, United Kingdom,Department of Movement Sciences, Faculty of Movement and Rehabilitation Sciences, Katholieke Universiteit (KU) Leuven, Leuven, Belgium,Willibald Gebhardt Research Institute, University of Münster, Münster, Germany,*Correspondence: Andrea Petróczi
| | - Maarten Cruyff
- Faculty of Social Sciences, Utrecht University, Utrecht, Netherlands
| | - Olivier de Hon
- Doping Authority Netherlands, Capelle aan den IJssel, Netherlands
| | - Dominic Sagoe
- Department of Psychosocial Science, University of Bergen, Bergen, Norway
| | - Martial Saugy
- Research and Expertise in anti-Doping Sciences (REDs), Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
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Eddin FBK, Fen YW, Liew JYC, Daniyal WMEMM. Plasmonic Refractive Index Sensor Enhanced with Chitosan/Au Bilayer Thin Film for Dopamine Detection. Biosensors (Basel) 2022; 12:1124. [PMID: 36551091 PMCID: PMC9775628 DOI: 10.3390/bios12121124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/25/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Surface plasmonic sensors have received considerable attention, found extensive applications, and outperformed conventional optical sensors. In this work, biopolymer chitosan (CS) was used to prepare the bilayer structure (CS/Au) of a plasmonic refractive index sensor for dopamine (DA) detection. The sensing characteristics of the developed plasmonic sensor were evaluated. Increasing DA concentrations significantly shifted the SPR dips. The sensor exhibited stability and a refractive index sensitivity of 8.850°/RIU in the linear range 0.1 nM to 1 µM with a detection limit of 0.007 nM and affinity constant of 1.383 × 108 M-1. The refractive index and thickness of the CS/Au structure were measured simultaneously by fitting the obtained experimental findings to theoretical data based on Fresnel equations. The fitting yielded the refractive index values n (1.5350 ± 0.0001) and k (0.0150 ± 0.0001) for the CS layer contacting 0.1 nM of DA, and the thickness, d was (15.00 ± 0.01) nm. Then, both n and d values increased by increasing DA concentrations. In addition, the changes in the FTIR spectrum and the variations in sensor surface roughness and structure obtained by AFM analysis confirmed DA adsorption on the sensing layer. Based on these observations, CS/Au bilayer has enhanced the performance of this plasmonic sensor, which showed promising importance as a simple, low-cost, and reliable platform for DA sensing.
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Affiliation(s)
- Faten Bashar Kamal Eddin
- Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Yap Wing Fen
- Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
- Functional Nanotechnology Devices Laboratory, Institute of Nanoscience and Nanotechnology, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Josephine Ying Chyi Liew
- Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
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Aguilar-Navarro M, Salas-Montoro JA, Pino-Ortega J, Salinero JJ, González-Mohíno F, Alcaraz-Rodríguez V, Moreno-Pérez D, Lanza N, Lara B, Moreno-Pérez V, Romero-Moraleda B, Pérez-López A, García-Martí C, Del Coso J. Anti-Doping Knowledge of Students Undertaking Bachelor's Degrees in Sports Sciences in Spain. Nutrients 2022; 14. [PMID: 36364784 DOI: 10.3390/nu14214523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/17/2022] [Accepted: 10/18/2022] [Indexed: 11/17/2022] Open
Abstract
In Spain, students pursuing a career in athletic training, physical education, or scientific evaluation of sports enroll in a bachelor’s degree in sports sciences. This degree provides knowledge and skills in a broad array of sports settings and promotes research-based interdisciplinary knowledge. However, the student’s syllabus rarely includes specific academic training on anti-doping regulations or doping prevention. The purpose of this study was to assess the anti-doping knowledge of the students undertaking a bachelor’s degree in sports sciences in Spanish universities. One thousand two hundred and thirty-three bachelor students in sport science (907 males, 322 females, and 4 participants with non-binary sex) from 26 Spanish universities completed a validated questionnaire about general anti-doping knowledge. The questionnaire is an adapted version of the Play True Quiz of the World Anti-Doping Agency and contains 37 multiple-choice questions. The score obtained in the questionnaire was transformed into a 0−100-point scale. The questionnaire was distributed among students within each university by a faculty member and it was filled out online. Students obtained a score of 65.8 ± 10.10 points (range = 32−92 points). There was an effect of the course in the score obtained (p < 0.001). Students of the first course (63.6 ± 9.5 points) had lower scores than the remaining courses (p < 0.037) while the students of the fourth course obtained the highest scores (68.7 ± 9.5 points; p < 0.019). The students with an itinerary on sports performance were the respondents with the highest anti-doping knowledge (67.2 ± 10.2) points, followed by the students with an itinerary on health (66.7 ± 9.5 points). The knowledge of basic anti-doping rules and doping prevention strategies of the bachelor students in sports sciences in Spain was suboptimal. Increasing doping prevention information in the syllabus of the bachelor’s degree in sports sciences is essential as these future professionals will directly work with populations at risk of doping.
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Xi Y, Lu Y. Electrochemically Active Mn-Doped Iron Hexacyanoferrate as the Cathode Material in Sodium-Ion Batteries. ACS Appl Mater Interfaces 2022; 14:39022-39030. [PMID: 35980972 DOI: 10.1021/acsami.2c07779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In this work, for the performance enhancement of iron hexacyanoferrate, an electrochemically active Mn-doped iron hexacyanoferrate cathode is fabricated via a bottom-up approach. It is found that the pre-treatment of interstitial water and appropriate Mn doping are two keys to achieving higher capacity and higher stability. The interstitial water has a trade-off effect between the alleviation of volume expansion upon Na+ (de)intercalation and the retardation of Na-ion diffusion. The moisture-tailored iron hexacyanoferrate with appropriate Mn doping exhibits a high initial Coulombic efficiency of 94.8%, enhanced capacity and rate performance, and excellent cycling stability. These results benefit from the fact that the extraction/insertion of Na ions from/into the lattice via a solid-solution mechanism correspond to both the slight volume expansion and fast sodium diffusion rate; otherwise, the removal of interstitial water and a higher Mn content might lead to poor cycling stability due to excessive volume expansion resulting from rhombohedral to cubic phase transformation. Finally, the less demand on the control of air humidity for the fabrication of electrodes and the potential for the full cell coupled with hard carbon are also demonstrated, which shows great potential for practical applications.
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Affiliation(s)
- Yuming Xi
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Yangcheng Lu
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
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Ju Y, Babaei-Mahani R, Ibrahem RK, Khakberdieva S, Karim YS, Abdalla AN, Mohamed A, Mahmoud MZ, Ali HM. Discharge Enhancement in a Triple-Pipe Heat Exchanger Filled with Phase Change Material. Nanomaterials (Basel) 2022; 12:1605. [PMID: 35564313 DOI: 10.3390/nano12091605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 02/04/2023]
Abstract
This study aims to study the discharging process to verify the influence of geometry modifications and heat transfer flow (HTF) patterns on the performance of a vertical triplex-tube latent heat container. The phase change material (PCM) is included in the middle tube, where the geometry is modified using single or multi-internal frustum tubes instead of straight tubes to enhance the discharging rate. The effects of the HTF flow direction, which is considered by the gravity and opposite-gravity directions, are also examined in four different cases. For the optimal geometry, three scenarios are proposed, i.e., employing a frustum tube for the middle tube, for the inner tube, and at last for both the inner and middle tubes. The effects of various gap widths in the modified geometries are investigated. The results show the advantages of using frustum tubes in increasing the discharging rate and reducing the solidification time compared with that of the straight tube unit due to the higher natural convection effect by proper utilization of frustum tubes. The study of the HTF pattern shows that where the HTF direction in both the inner and outer tubes are in the gravity direction, the maximum discharging rate can be achieved. For the best configuration, the discharge time is reduced negligibly compared with that for the system with straight tubes which depends on the dimensions of the PCM domain.
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Hurst P, Ring C, Kavussanu M. Moral values and moral identity moderate the indirect relationship between sport supplement use and doping use via sport supplement beliefs. J Sports Sci 2022; 40:1160-1167. [PMID: 35301930 DOI: 10.1080/02640414.2022.2053387] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The Incremental Model of Doping Behaviour suggests doping grows out of the habitual use of performance-enhancing methods (e.g., sport supplements) and belief that they are necessary for performance. Importantly, in this model, doping is viewed as functional rather than moral choice. In two studies, we examined whether sport supplement use was indirectly related to doping use via sport supplement beliefs, and whether personal morality moderated this relationship. Competitive athletes (Study 1, N = 366; Study 2, N = 200) completed measures of supplement use, beliefs, and doping use. They also completed measures of moral values (Study 1) and moral identity (Study 2). In both studies, supplement use was indirectly related to doping use via beliefs. Moreover, this indirect relationship was moderated by moral values (Study 1) and moral identity (Study 2). That is, the relationship between supplement use and doping use via beliefs was negated when moral values and moral identity were high but not when they were low or moderate. Taken together, our findings suggest that sport supplement users, who believe they are necessary, are more likely to dope if they have low moral values and believe that being a moral person is unimportant to their self-image.
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Affiliation(s)
- Philip Hurst
- School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, UK
| | - Christopher Ring
- School of Sport, Exercise & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Maria Kavussanu
- School of Sport, Exercise & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
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Wu SH, Chen KL, Hsu C, Chen HC, Chen JY, Yu SY, Shiu YJ. Creatine Supplementation for Muscle Growth: A Scoping Review of Randomized Clinical Trials from 2012 to 2021. Nutrients 2022; 14:1255. [PMID: 35334912 DOI: 10.3390/nu14061255] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/10/2022] [Accepted: 03/14/2022] [Indexed: 02/07/2023] Open
Abstract
Creatine supplementation is the most popular ergonomic aid for athletes in recent years and is used for improving sport performance and muscle growth. However, creatine supplementation is not always effective in all populations. To address these discrepancies, numerous studies have examined the use of creatine supplementation for muscle growth. This scoping review aimed to investigate the effects of creatine supplementation for muscle growth in various populations, in which Arksey and O'Malley's scoping review framework is used to present the findings. For this study, we performed a systematic search of the PubMed, Embase, and Web of Science databases for theses and articles published between 2012 and 2021. A manual search of the reference lists of the uncovered studies was conducted and an expert panel was consulted. Two reviewers screened the articles for eligibility according to the inclusion criteria. Methodological quality was assessed using the National Heart, Lung and Blood Institute's (NHLBI's) quality assessment tool. A total of 16 randomized controlled trials (RCTs) were finally included. All the authors extracted key data and descriptively analyzed the data. Thematic analysis was used to categorize the results into themes. Three major themes related to muscle growth were generated: (i) subjects of creatine supplementation-muscle growth is more effective in healthy young subjects than others; (ii) training of subjects-sufficient training is important in all populations; (iii) future direction and recommendation of creatine supplementation for muscle growth-injury prevention and utilization in medical practice. Overall, creatine is an efficient form of supplementation for muscle growth in the healthy young population with adequate training in a variety of dosage strategies and athletic activities. However, more well-designed, long-term RCTs with larger sample sizes are needed in older and muscular disease-related populations to definitively determine the effects of creatine supplementation on muscle growth in these other populations.
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Md Aspan R, Fatima N, Mohamed R, Syafiq U, Ibrahim MA. An Overview of the Strategies for Tin Selenide Advancement in Thermoelectric Application. Micromachines (Basel) 2021; 12:1463. [PMID: 34945312 PMCID: PMC8709453 DOI: 10.3390/mi12121463] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/19/2021] [Accepted: 11/20/2021] [Indexed: 11/17/2022]
Abstract
Chalcogenide, tin selenide-based thermoelectric (TE) materials are Earth-abundant, non-toxic, and are proven to be highly stable intrinsically with ultralow thermal conductivity. This work presented an updated review regarding the extraordinary performance of tin selenide in TE applications, focusing on the crystal structures and their commonly used fabrication methods. Besides, various optimization strategies were recorded to improve the performance of tin selenide as a mid-temperature TE material. The analyses and reviews over the methodologies showed a noticeable improvement in the electrical conductivity and Seebeck coefficient, with a noticeable decrement in the thermal conductivity, thereby enhancing the tin selenide figure of merit value. The applications of SnSe in the TE fields such as microgenerators, and flexible and wearable devices are also discussed. In the future, research in low-dimensional TE materials focusing on nanostructures and nanocomposites can be conducted with the advancements in material science technology as well as microtechnology and nanotechnology.
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Affiliation(s)
- Rosnita Md Aspan
- Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia; (R.M.A.); (N.F.); (U.S.)
| | - Noshin Fatima
- Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia; (R.M.A.); (N.F.); (U.S.)
| | - Ramizi Mohamed
- Department of Electrical, Electronics and System Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia;
| | - Ubaidah Syafiq
- Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia; (R.M.A.); (N.F.); (U.S.)
| | - Mohd Adib Ibrahim
- Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia; (R.M.A.); (N.F.); (U.S.)
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30
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Zhu Z, Svensson J, Jönsson A, Wernersson LE. Performance enhancement of GaSb vertical nanowire p-type MOSFETs on Si by rapid thermal annealing. Nanotechnology 2021; 33:075202. [PMID: 34736238 DOI: 10.1088/1361-6528/ac3689] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/04/2021] [Indexed: 06/13/2023]
Abstract
GaSb is considered as an attractive p-type channel material for future III-V metal-oxide-semiconductor (MOS) technologies, but the processing conditions to utilize the full device potential such as low power logic applications and RF applications still need attention. In this work, applying rapid thermal annealing (RTA) to nanoscale GaSb vertical nanowire p-type MOS field-effect transistors, we have improved the average peak transconductance (gm,peak) by 50% among 28 devices and achieved 70μSμm-1atVDS = -0.5 V in a device with 200 nm gate length. In addition, a low subthreshold swing down to 144 mV dec-1as well as an off-current below 5 nAμm-1which refers to the off-current specification in low-operation-power condition has been obtained. Based on the statistical analysis, the results show a great enhancement in both on- and off-state performance with respect to previous work mainly due to the improved electrostatics and contacts after RTA, leading to a potential in low-power logic applications. We have also examined a short channel device withLg = 80 nm in RTA, which shows an increasedgm,peakup to 149μSμm-1atVDS = -0.5 V as well as a low on-resistance of 4.7 kΩ·μm. The potential of further enhancement ingmvia RTA offers a good alternative to obtain high-performance devices for RF applications which have less stringent requirement for off-state performance. Our results indicate that post-fabrication annealing provides a great option to improve the performance of GaSb-based p-type devices with different structures for various applications.
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Affiliation(s)
- Zhongyunshen Zhu
- Division of Electromagnetics and Nanoelectronics, Department of Electrical and Information Technology, Lund University, 221 00 Lund, Sweden
| | - Johannes Svensson
- Division of Electromagnetics and Nanoelectronics, Department of Electrical and Information Technology, Lund University, 221 00 Lund, Sweden
| | - Adam Jönsson
- Division of Electromagnetics and Nanoelectronics, Department of Electrical and Information Technology, Lund University, 221 00 Lund, Sweden
| | - Lars-Erik Wernersson
- Division of Electromagnetics and Nanoelectronics, Department of Electrical and Information Technology, Lund University, 221 00 Lund, Sweden
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31
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Kimura A, Yokozawa T, Ozaki H. Clarifying the Biomechanical Concept of Coordination Through Comparison With Coordination in Motor Control. Front Sports Act Living 2021; 3:753062. [PMID: 34723181 PMCID: PMC8551718 DOI: 10.3389/fspor.2021.753062] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 09/16/2021] [Indexed: 12/02/2022] Open
Abstract
Coordination is a multidisciplinary concept in human movement science, particularly in the field of biomechanics and motor control. However, the term is not used synonymously by researchers and has substantially different meanings depending on the studies. Therefore, it is necessary to clarify the meaning of coordination to avoid confusion. The meaning of coordination in motor control from computational and ecological perspectives has been clarified, and the meanings differed between them. However, in biomechanics, each study has defined the meaning of the term and the meanings are diverse, and no study has attempted to bring together the diversity of the meanings of the term. Therefore, the purpose of this study is to provide a summary of the different meanings of coordination across the theoretical landscape and clarify the meaning of coordination in biomechanics. We showed that in biomechanics, coordination generally means the relation between elements that act toward the achievement of a motor task, which we call biomechanical coordination. We also showed that the term coordination used in computational and ecological perspectives has two different meanings, respectively. Each one had some similarities with biomechanical coordination. The findings of this study lead to an accurate understanding of the concept of coordination, which would help researchers formulate their empirical arguments for coordination in a more transparent manner. It would allow for accurate interpretation of data and theory development. By comprehensively providing multiple perspectives on coordination, this study intends to promote coordination studies in biomechanics.
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Affiliation(s)
- Arata Kimura
- Department of Sports Research, Japan Institute of Sports Sciences, Tokyo, Japan
| | - Toshiharu Yokozawa
- Department of Sports Research, Japan Institute of Sports Sciences, Tokyo, Japan
| | - Hiroki Ozaki
- Department of Sports Research, Japan Institute of Sports Sciences, Tokyo, Japan
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32
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Moen J. An Ergogenic Medical Education: Building Curricula to Optimize Performance and Decrease Burnout. Cureus 2021; 13:e17855. [PMID: 34660060 PMCID: PMC8502734 DOI: 10.7759/cureus.17855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2021] [Indexed: 11/05/2022] Open
Abstract
One of the most pervasive myths in our culture today is the belief that training increases performance. When, in fact, training decreases performance. The current structure of training programs and educational curriculums provide the evidence regarding the acceptance of this belief. Intense focus is placed on the quantity of training time with little regard for additional factors. In pursuit of excellence, maximizing training opportunity and learning exposure insists upon the sacrifice of recovery time. However, recovery is the necessary training period to increase performance. In athletics, training without recovery leads to overtraining syndrome. Burnout is the non-athletic equivalency seen in under-recovered learners and workers. As demonstrated by the climbing burnout rates, the current structure of educational programs, epitomized by medical residency, perpetuates the myth that more training equals better performance. The purpose of the article does not revolve around the presentation of novel research discoveries, but it insists upon the implementation of previously established performance data in curricula development beyond athletics. The inflection and deflection points along the growth and adaptation curves can be explicitly utilized to meet the educational and professional standards set forth by educational institutions. When tracking performance as the metric, initial training stimuli creates a descending slope, e.g., "training decreases performance." The concept that training creates a negative deflection is a neglected concept in academics. By incorporating this feature into learning environments, training can transition from surviving training redundancy to thriving with an optimal work:recovery ratio.
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Affiliation(s)
- Joshua Moen
- College of Health Education, Touro University California, Vallejo, USA
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Ogasawara I, Hamaguchi S, Hasegawa R, Akeda Y, Ota N, Revankar GS, Konda S, Taguchi T, Takanouchi T, Imoto K, Okimoto N, Sakuma K, Uchiyama A, Yamasaki K, Higashino T, Tomono K, Nakata K. Successful Reboot of High-Performance Sporting Activities by Japanese National Women's Handball Team in Tokyo, 2020 during the COVID-19 Pandemic: An Initiative Using the Japan Sports-Cyber Physical System (JS-CPS) of the Sports Research Innovation Project (SRIP). Int J Environ Res Public Health 2021; 18:9865. [PMID: 34574789 PMCID: PMC8468396 DOI: 10.3390/ijerph18189865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/10/2021] [Accepted: 09/14/2021] [Indexed: 11/18/2022]
Abstract
The COVID-19 pandemic has negatively impacted sporting activities across the world. However, practical training strategies for athletes to reduce the risk of infection during the pandemic have not been definitively studied. The purpose of this report was to provide an overview of the challenges we encountered during the reboot of high-performance sporting activities of the Japanese national handball team during the 3rd wave of the COVID-19 pandemic in Tokyo, Japan. Twenty-nine Japanese national women's handball players and 24 staff participated in the study. To initiate the reboot of their first training camp after COVID-19 stay-home social policy, we conducted: web-based health-monitoring, SARS-CoV-2 screening with polymerase chain reaction (PCR) tests, real-time automated quantitative monitoring of social distancing on court using a moving image-based artificial intelligence (AI) algorithm, physical intensity evaluation with wearable heart rate (HR) and acceleration sensors, and a self-reported online questionnaire. The training camp was conducted successfully with no COVID-19 infections. The web-based health monitoring and the frequent PCR testing with short turnaround times contributed remarkably to early detection of athletes' health problems and to risk screening. During handball, AI-based on-court social-distance monitoring revealed key time-dependent spatial metrics to define player-to-player proximity. This information facilitated appropriate on- and off-game distancing behavior for teammates. Athletes regularly achieved around 80% of maximum HR during training, indicating anticipated improvements in achieving their physical intensities. Self-reported questionnaires related to the COVID management in the training camp revealed a sense of security among the athletes that allowed them to focus singularly on their training. The challenges discussed herein provided us considerable knowledge about creating and managing a safe environment for high-performing athletes in the COVID-19 pandemic via the Japan Sports-Cyber Physical System (JS-CPS) of the Sports Research Innovation Project (SRIP, Japan Sports Agency, Tokyo, Japan). This report is envisioned to provide informed decisions to coaches, trainers, policymakers from the sports federations in creating targeted, infection-free, sporting and training environments.
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Affiliation(s)
- Issei Ogasawara
- Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (I.O.); (G.S.R.); (S.K.); (K.Y.)
| | - Shigeto Hamaguchi
- Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (S.H.); (Y.A.); (N.O.); (K.T.)
- Division of Infection Control and Prevention, Osaka University Hospital, Osaka 5650871, Japan
| | - Ryosuke Hasegawa
- Department of Information Networking, Graduate School of Information Science and Technology, Osaka University, Osaka 5650871, Japan;
| | - Yukihiro Akeda
- Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (S.H.); (Y.A.); (N.O.); (K.T.)
- Division of Infection Control and Prevention, Osaka University Hospital, Osaka 5650871, Japan
- Japan-Thailand Research Collaboration Centre on Emerging and Re-Emerging Infections, Research Institute for Microbial Diseases, Osaka University, Osaka 5650871, Japan; (A.U.); (T.H.)
| | - Naoki Ota
- Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (S.H.); (Y.A.); (N.O.); (K.T.)
| | - Gajanan S. Revankar
- Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (I.O.); (G.S.R.); (S.K.); (K.Y.)
- Institute for Transdisciplinary Graduate Degree Programs, Osaka University, Osaka 5650871, Japan
| | - Shoji Konda
- Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (I.O.); (G.S.R.); (S.K.); (K.Y.)
| | - Takashi Taguchi
- Japan Handball Association, Tokyo 1600013, Japan; (T.T.); (T.T.); (K.I.); (N.O.); (K.S.)
- Faculty of Economics and Information, Gifu Shotoku Gakuen University, Gifu 5008288, Japan
| | - Toshiya Takanouchi
- Japan Handball Association, Tokyo 1600013, Japan; (T.T.); (T.T.); (K.I.); (N.O.); (K.S.)
- T-function Inc., Tokyo 1560042, Japan
| | - Kojiro Imoto
- Japan Handball Association, Tokyo 1600013, Japan; (T.T.); (T.T.); (K.I.); (N.O.); (K.S.)
- Department of Orthopedic Surgery, Japanese Red Cross Kumamoto Hospital, Kumamoto 8618520, Japan
| | - Nobukazu Okimoto
- Japan Handball Association, Tokyo 1600013, Japan; (T.T.); (T.T.); (K.I.); (N.O.); (K.S.)
- Medical Corporation Okimoto Clinic, Hiroshima 7340304, Japan
| | - Katsuhiko Sakuma
- Japan Handball Association, Tokyo 1600013, Japan; (T.T.); (T.T.); (K.I.); (N.O.); (K.S.)
- Department of Rehabilitation, Medical Corporation Yamabe-Kai, Kumamoto Seijo Hospital, Kumamoto 8618072, Japan
| | - Akira Uchiyama
- Japan-Thailand Research Collaboration Centre on Emerging and Re-Emerging Infections, Research Institute for Microbial Diseases, Osaka University, Osaka 5650871, Japan; (A.U.); (T.H.)
| | - Keita Yamasaki
- Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (I.O.); (G.S.R.); (S.K.); (K.Y.)
| | - Teruo Higashino
- Japan-Thailand Research Collaboration Centre on Emerging and Re-Emerging Infections, Research Institute for Microbial Diseases, Osaka University, Osaka 5650871, Japan; (A.U.); (T.H.)
| | - Kazunori Tomono
- Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (S.H.); (Y.A.); (N.O.); (K.T.)
- Division of Infection Control and Prevention, Osaka University Hospital, Osaka 5650871, Japan
| | - Ken Nakata
- Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan; (I.O.); (G.S.R.); (S.K.); (K.Y.)
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Ketelhut S, Martin-Niedecken AL, Zimmermann P, Nigg CR. Physical Activity and Health Promotion in Esports and Gaming-Discussing Unique Opportunities for an Unprecedented Cultural Phenomenon. Front Sports Act Living 2021; 3:693700. [PMID: 34604743 PMCID: PMC8481377 DOI: 10.3389/fspor.2021.693700] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 08/23/2021] [Indexed: 12/29/2022] Open
Abstract
Due to long periods of sedentary behavior, and unhealthy diets gamers and esports players are at risk for numerous chronic diseases and all-cause mortality. Health research has started addressing the public health implications of the esports phenomenon, drawing a bleak picture of this megatrend. However, instead of just highlighting adverse public health implications of this trend, it is recommended to become involved in this phenomenon and positively influence it. Esports has an enormous potential for physical activity and health-promoting efforts, provides a context for broadly disseminating interventions, and offers new ways of gaining access to an often-neglected population. This paper presents: the potential of the esports phenomenon to promote physical activity, health, and well-being in gamers and esports players; the strategic and preventive solutions to ameliorate esports possible adverse health impacts; and the utilization of esports technology (streams, media platforms, exergames, etc.) as an innovative health promotion tool, especially reaching gamers and esports players with attractive and interactive interventions. This is to encourage systematic scientific research so that evidence-based guidelines and intervention strategies involving regular physical activity, healthy diet, and sleep hygiene for esports will be developed. The goal is to promote public health approaches that move toward a better integration of esports and gaming.
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Affiliation(s)
- Sascha Ketelhut
- Department of Health Science, Institute of Sport Science, University of Bern, Bern, Switzerland
| | | | - Patrick Zimmermann
- Department of Health Science, Institute of Sport Science, University of Bern, Bern, Switzerland
| | - Claudio R. Nigg
- Department of Health Science, Institute of Sport Science, University of Bern, Bern, Switzerland
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Li T, Luo S, Wang X, Zhang L. Alternative Lone-Pair ns 2 -Cation-Based Semiconductors beyond Lead Halide Perovskites for Optoelectronic Applications. Adv Mater 2021; 33:e2008574. [PMID: 34060151 DOI: 10.1002/adma.202008574] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Lead halide perovskites have emerged in the last decade as advantageous high-performance optoelectronic semiconductors, and have undergone rapid development for diverse applications such as solar cells, light-emitting diodes , and photodetectors. While material instability and lead toxicity are still major concerns hindering their commercialization, they offer promising prospects and design principles for developing promising optoelectronic materials. The distinguished optoelectronic properties of lead halide perovskites stem from the Pb2+ cation with a lone-pair 6s2 electronic configuration embedded in a mixed covalent-ionic bonding lattice. Herein, we summarize alternative Pb-free semiconductors containing lone-pair ns2 cations, intending to offer insights for developing potential optoelectronic materials other than lead halide perovskites. We start with the physical underpinning of how the ns2 cations within the material lattice allow for superior optoelectronic properties. We then review the emerging Pb-free semiconductors containing ns2 cations in terms of structural dimensionality, which is crucial for optoelectronic performance. For each category of materials, the research progresses on crystal structures, electronic/optical properties, device applications, and recent efforts for performance enhancements are overviewed. Finally, the issues hindering the further developments of studied materials are surveyed along with possible strategies to overcome them, which also provides an outlook on the future research in this field.
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Affiliation(s)
- Tianshu Li
- State Key Laboratory of Integrated Optoelectronics, Key Laboratory of Automobile Materials of MOE, and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China
| | - Shulin Luo
- State Key Laboratory of Integrated Optoelectronics, Key Laboratory of Automobile Materials of MOE, and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China
| | - Xinjiang Wang
- State Key Laboratory of Integrated Optoelectronics, Key Laboratory of Automobile Materials of MOE, and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China
| | - Lijun Zhang
- State Key Laboratory of Integrated Optoelectronics, Key Laboratory of Automobile Materials of MOE, and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China
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Lundgren T, Reinebo G, Fröjmark MJ, Jäder E, Näslund M, Svartvadet P, Samuelsson U, Parling T. Acceptance and Commitment Training for Ice Hockey Players: A Randomized Controlled Trial. Front Psychol 2021; 12:685260. [PMID: 34367007 PMCID: PMC8339210 DOI: 10.3389/fpsyg.2021.685260] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/30/2021] [Indexed: 11/13/2022] Open
Abstract
Recent systematic reviews on the topic of mindfulness- and acceptance-based approaches in sport psychology conclude that there is a need for further trials using a more robust research methodology with direct performance as outcome. Acceptance and Commitment Training (ACT) is a contextual behavioral change method that focuses on facilitating psychological processes such as values, committed action, acceptance and mindfulness. In the present study designed as a randomized controlled trial, 34 junior elite ice hockey players were allocated into either an ACT group intervention or a wait list control group. Results showed significant effects on both objective performance outcomes (goals, assists, and taken shots) and blinded coach ratings of players' performance, focus and commitment to their development in favor of the ACT group. Effects lasted at 3-month follow-up for the coach ratings, but not for the objective performance measures. All ACT trained players recommended ACT to other players and considered the training as important for their development as ice hockey players. The results add to the growing body of evidence on ACT interventions for athletes and its effect on performance. Future studies should investigate the maintenance of effects from the psychological training over time, using robust research methodology and investigate theoretical coherent potential mediating variables.
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Affiliation(s)
- Tobias Lundgren
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
- Department of Psychology, Stockholm University, Stockholm, Sweden
| | - Gustaf Reinebo
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
| | - Markus Jansson Fröjmark
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
| | - Emil Jäder
- Department of Psychology, Stockholm University, Stockholm, Sweden
| | | | | | | | - Thomas Parling
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
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Shelley J, Thrower SN, Petróczi A. Racing Clean in a Tainted World: A Qualitative Exploration of the Experiences and Views of Clean British Elite Distance Runners on Doping and Anti-Doping. Front Psychol 2021; 12:673087. [PMID: 34305727 PMCID: PMC8296639 DOI: 10.3389/fpsyg.2021.673087] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 06/10/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Doping has been a prominent issue for the sport of athletics in recent years. The endurance disciplines, which currently account for 56% of the global anti-doping rule violations in athletics, appear to be particularly high risk for doping. Objective: Using this high-risk, high-pressure context, the main purpose of this study was to investigate the human impact of doping and anti-doping on "clean" athletes. The secondary aim of the study was to better understand the reasons for, and barriers to, competing "clean" among this group of athletes. Method: Semi-structured interviews were conducted with 11 elite distance runners from the UK to explore: (1) the reasons and motivations for competing clean. (2) Perceptions of the anti-doping system, and experiences of being part of that system. (3) Views on the prevalence and causes of doping and the impact of doping on the lives of clean athletes. The interviews were audio-recorded, transcribed verbatim, and analysed using Reflexive Thematic Analysis. Results: Four major themes were identified: (1) The participants in this study have not been tempted to use prohibited substances or methods; they compete in their sport for the personal satisfaction of seeing how good they can be, rather than in pursuit of winning at all costs. (2) Anti-doping does not currently prevent doping effectively and is not implemented evenly across the globe. (3) Doping was perceived as a major issue and was felt to be borne out of certain sporting cultures in which doping is enabled. (4) Doping has impacted the careers of clean athletes in irreversible ways and presents a continuing challenge to the psychological preparation for competition. Conclusions: Clean athletes suffer negative consequences from both doping and anti-doping. ADOs must collaborate across borders to ensure a more even implementation of anti-doping activities, to facilitate a more level playing field on the global stage. ADOs must also acknowledge the existence of a large group of athletes who would never consider deliberately doping and make anti-doping work for these athletes too.
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Affiliation(s)
- Jake Shelley
- School of Life Sciences, Engineering and Computing, Faculty of Science, Engineering and Computing, Kingston University, London, United Kingdom
| | - Sam N. Thrower
- Department of Life Sciences, University of Roehampton, London, United Kingdom
| | - Andrea Petróczi
- School of Life Sciences, Engineering and Computing, Faculty of Science, Engineering and Computing, Kingston University, London, United Kingdom
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Panessiti C, Rull-Garza M, Rickards G, Konow N. Thermal sensitivity of Axolotl feeding behaviors. Integr Comp Biol 2021; 61:1881-1891. [PMID: 34117757 DOI: 10.1093/icb/icab120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Musculoskeletal movement results from muscle contractions, recoil of elastic tendons, aponeuroses, and ligaments, or combinations thereof. Muscular and elastic contributions can vary both across behaviors and with changes in temperature. Skeletal muscles reach peak contraction speed at a temperature optimum with performance declining away from that optimum by approximately 50% per 10 °C, following the Q10 principle. Elastic recoil action, however, is less temperature sensitive. We subjected Axolotls (Ambystoma mexicanum) to changes from warm (23 °C), via medium (14 °C), to cold (6 °C) temperature across most of their thermal tolerance range, and recorded jaw kinematics during feeding on crickets. We sought to determine if suction feeding strikes and food processing chews involve elastic mechanisms and, specifically, if muscular versus elastic contribution vary with temperature for gape opening and closing. Measurements of peak and mean speed for gape opening and closing during strikes and chews across temperature treatments were compared to Q10-based predictions. We found that strike gape speed decreased significantly from warm and medium to cold treatments, indicating low thermal robustness, and no performance-enhancement due to elastic recoil. For chews, peak and mean gape closing speeds, as well as peak gape opening speed, also decreased significantly from warm to cold treatments. However, peak gape opening and closing speeds for chews showed performance-enhancement, consistent with a previously demonstrated presence of elastic action in the Axolotl jaw system. Our results add to a relatively small body of evidence suggesting that elastic recoil plays significant roles in aquatic vertebrate feeding systems, and in cyclic food processing mechanisms.
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Seiberl W, Hahn D, Power GA, Fletcher JR, Siebert T. Editorial: The Stretch-Shortening Cycle of Active Muscle and Muscle-Tendon Complex: What, Why and How It Increases Muscle Performance? Front Physiol 2021; 12:693141. [PMID: 34093246 PMCID: PMC8173190 DOI: 10.3389/fphys.2021.693141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 04/19/2021] [Indexed: 11/30/2022] Open
Affiliation(s)
- Wolfgang Seiberl
- Human Movement Science, Department of Human Sciences, Bundeswehr University Munich, Neubiberg, Germany
| | - Daniel Hahn
- Human Movement Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany.,School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Geoffrey A Power
- Neuromechanical Performance Research Laboratory, Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, Guelph, ON, Canada
| | - Jared R Fletcher
- Department of Health and Physical Education, Mount Royal University, Calgary, AB, Canada
| | - Tobias Siebert
- Department of Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany.,Center for Simulation Science, University of Stuttgart, Stuttgart, Germany
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Tomalka A, Weidner S, Hahn D, Seiberl W, Siebert T. Power Amplification Increases With Contraction Velocity During Stretch-Shortening Cycles of Skinned Muscle Fibers. Front Physiol 2021; 12:644981. [PMID: 33868012 PMCID: PMC8044407 DOI: 10.3389/fphys.2021.644981] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 03/08/2021] [Indexed: 01/25/2023] Open
Abstract
Muscle force, work, and power output during concentric contractions (active muscle shortening) are increased immediately following an eccentric contraction (active muscle lengthening). This increase in performance is known as the stretch-shortening cycle (SSC)-effect. Recent findings demonstrate that the SSC-effect is present in the sarcomere itself. More recently, it has been suggested that cross-bridge (XB) kinetics and non-cross-bridge (non-XB) structures (e.g., titin and nebulin) contribute to the SSC-effect. As XBs and non-XB structures are characterized by a velocity dependence, we investigated the impact of stretch-shortening velocity on the SSC-effect. Accordingly, we performed in vitro isovelocity ramp experiments with varying ramp velocities (30, 60, and 85% of maximum contraction velocity for both stretch and shortening) and constant stretch-shortening magnitudes (17% of the optimum sarcomere length) using single skinned fibers of rat soleus muscles. The different contributions of XB and non-XB structures to force production were identified using the XB-inhibitor Blebbistatin. We show that (i) the SSC-effect is velocity-dependent-since the power output increases with increasing SSC-velocity. (ii) The energy recovery (ratio of elastic energy storage and release in the SSC) is higher in the Blebbistatin condition compared with the control condition. The stored and released energy in the Blebbistatin condition can be explained by the viscoelastic properties of the non-XB structure titin. Consequently, our experimental findings suggest that the energy stored in titin during the eccentric phase contributes to the SSC-effect in a velocity-dependent manner.
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Affiliation(s)
- André Tomalka
- Department of Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany
| | - Sven Weidner
- Department of Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany
| | - Daniel Hahn
- Human Movement Science, Faculty of Sports Science, Ruhr University Bochum, Bochum, Germany
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Wolfgang Seiberl
- Human Movement Science, Bundeswehr University Munich, Neubiberg, Germany
| | - Tobias Siebert
- Department of Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany
- Stuttgart Center for Simulation Science, University of Stuttgart, Stuttgart, Germany
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Spörri J, Stöggl T, Aminian K. Editorial: Health and Performance Assessment in Winter Sports. Front Sports Act Living 2021; 3:628574. [PMID: 33768202 PMCID: PMC7985436 DOI: 10.3389/fspor.2021.628574] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/12/2021] [Indexed: 12/11/2022] Open
Affiliation(s)
- Jörg Spörri
- Sports Medical Research Group, Department of Orthopaedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,University Centre for Prevention and Sports Medicine, Department of Orthopaedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Thomas Stöggl
- Department of Sport Science and Kinesiology, University of Salzburg, Hallein, Austria.,Red Bull Athlete Performance Centre, Thalgau, Austria
| | - Kamiar Aminian
- Laboratory of Movement Analysis and Measurement, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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Lebares CC, Coaston TN, Delucchi KL, Guvva EV, Shen WT, Staffaroni AM, Kramer JH, Epel ES, Hecht FM, Ascher NL, Harris HW, Cole SW. Enhanced Stress Resilience Training in Surgeons: Iterative Adaptation and Biopsychosocial Effects in 2 Small Randomized Trials. Ann Surg 2021; 273:424-432. [PMID: 32773637 PMCID: PMC7863698 DOI: 10.1097/sla.0000000000004145] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE To determine the effects of ESRT (an iteratively adapted and tailored MBI) on perceived stress, executive cognitive function, psychosocial well-being (ie, burnout, mindfulness), and pro-inflammatory gene expression in surgical (ESRT-1) and mixed specialty (ESRT-2) PGY-1 volunteers. SUMMARY OF BACKGROUND AND DATA Tailored MBIs have proven beneficial in multiple high-stress and high-performance populations. In surgeons, tailored MBIs have been shown to be feasible and potentially beneficial, but whether mindfulness-based cognitive training can improve perceived stress, executive function, well-being or physiological distress in surgical and nonsurgical trainees is unknown. METHODS In 2 small single-institution randomized clinical trials, ESRT, a tailored mindfulness-based cognitive training program, was administered and iteratively adapted for first-year surgical (ESRT-1, 8 weekly, 2-hour classes, n = 44) and mixed specialty (ESRT-2, 6 weekly, 90-minute classes, n = 45) resident trainees. Primary and secondary outcomes were, respectively, perceived stress and executive function. Other prespecified outcomes were burnout (assessed via Maslach Burnout Inventory), mindfulness (assessed via Cognitive Affective Mindfulness Scale - Revised), and pro-inflammatory gene expression (assessed through the leukocyte transcriptome profile "conserved transcriptional response to adversity"). RESULTS Neither version of ESRT appeared to affect perceived stress. Higher executive function and mindfulness scores were seen in ESRT-1, and lower emotional exhaustion and depersonalization scores in ESRT-2, at pre-/postintervention and/or 50-week follow-up (ESRT-1) or at 32-week follow-up (ESRT-2), compared to controls. Pooled analysis of both trials found ESRT-treated participants had reduced pro-inflammatory RNA expression compared to controls. CONCLUSIONS This pilot work suggests ESRT can variably benefit executive function, burnout, and physiologic distress in PGY-1 trainees, with potential for tailoring to optimize effects.
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Affiliation(s)
- Carter C Lebares
- Department of Surgery, University of California San Francisco, San Francisco, California
| | - Troy N Coaston
- Department of Surgery, University of California San Francisco, San Francisco, California
| | - Kevin L Delucchi
- Department of Psychiatry, University of California San Francisco, San Francisco, California
| | - Ekaterina V Guvva
- Department of Surgery, University of California San Francisco, San Francisco, California
| | - Wen T Shen
- Department of Surgery, University of California San Francisco, San Francisco, California
| | - Adam M Staffaroni
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, California
| | - Joel H Kramer
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, California
| | - Elissa S Epel
- Department of Psychiatry, University of California San Francisco, San Francisco, California
- Osher Center for Integrated Medicine, University of California San Francisco, San Francisco, California
| | - Frederick M Hecht
- Department of Internal Medicine, University of California San Francisco, San Francisco, California
- Osher Center for Integrated Medicine, University of California San Francisco, San Francisco, California
| | - Nancy L Ascher
- Department of Surgery, University of California San Francisco, San Francisco, California
| | - Hobart W Harris
- Department of Surgery, University of California San Francisco, San Francisco, California
| | - Steven W Cole
- Department of Psychiatry & Biobehavioral Sciences, and Department of Medicine, University of California, Los Angeles
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Silva N, Travassos B, Gonçalves B, Brito J, Abade E. Pre-match Warm-Up Dynamics and Workload in Elite Futsal. Front Psychol 2020; 11:584602. [PMID: 33324293 PMCID: PMC7726253 DOI: 10.3389/fpsyg.2020.584602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 10/29/2020] [Indexed: 01/26/2023] Open
Abstract
Warming up prior to competition is a widely accepted strategy to increase players’ readiness and achieve high performances. However, pre-match routines are commonly based on empirical knowledge and strongly influenced by models emerging from elite team practices. The aim of the present study was to identify and analyze current pre-match warm-up practices in elite futsal. Forty-three elite players were analyzed during their pre-match warm-up routines during the Portuguese Futsal Cup Final 8. Warm-up tasks were classified according to duration, type of activity, sequence, and structure. External load variables included the total distance covered, total distance covered per minute, running distance per minute, sprinting distance per minute, number of accelerations per minute, and number of decelerations per minute. Results highlighted that warm-up routines lasted for 27.5 ± 9.2 min and included nine major different tasks. Open-skill activities were prioritized by coaches; competitive and non-competitive futsal-specific tasks were included in 90% of the total warm-up routines, with higher focus on non-competitive tasks (68% of total time). The intensity progressively increased during warm-ups, mainly because of the higher number of accelerations and decelerations per minute. Pre-match warm-up routines strongly endorse futsal-specific and representative tasks in order to establish pre-match settings able to prepare players for the upcoming game. When designing pre-match warm-up routines, coaches should be aware that duration, sequence, and type of tasks may affect players’ acute performance and readiness.
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Affiliation(s)
- Nuno Silva
- Research in Sports Sciences, Health Sciences and Human Development, CIDESD, University Institute of Maia, ISMAI, Maia, Portugal
| | - Bruno Travassos
- Department of Sports Sciences, Research Center in Sports Sciences, Health Sciences and Human Development (CIDESD), University of Beira Interior, Covilhã, Portugal.,Portugal Football School, Portuguese Football Federation, Oeiras, Portugal
| | - Bruno Gonçalves
- Portugal Football School, Portuguese Football Federation, Oeiras, Portugal.,Departamento de Desporto e Saúde, Escola de Ciências e Tecnologia, Universidade de Évora, Évora, Portugal.,Comprehensive Health Research Centre (CHRC), Universidade de Évora, Évora, Portugal
| | - João Brito
- Portugal Football School, Portuguese Football Federation, Oeiras, Portugal
| | - Eduardo Abade
- Research in Sports Sciences, Health Sciences and Human Development, CIDESD, University Institute of Maia, ISMAI, Maia, Portugal
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Ste-Marie DM, Lelievre N, St Germain L. Revisiting the Applied Model for the Use of Observation: A Review of Articles Spanning 2011-2018. Res Q Exerc Sport 2020; 91:594-617. [PMID: 32004119 DOI: 10.1080/02701367.2019.1693489] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 11/08/2019] [Indexed: 06/10/2023]
Abstract
Purpose: To provide a review of current articles that have used observation interventions to enhance motor skill acquisition or performance of applied tasks, and to situate the research within the Applied Model for the Use of Observation (AMUO) with the goal of forming a basis for evidence-based guidelines for practitioners. Method: Key words (e.g., observation/modeling) were searched in varied data bases (e.g., Google Scholar/PubMed), along with a citation search of the relevant AMUO article, to generate a pool of articles for possible review. Selection criteria included publication between 2011 and 2018, and that the research focus was on the effects of an observation intervention on the acquisition or performance of an applied motor task. Results: Forty-eight articles were reviewed, with 21 of these targeting the basic question of whether observation is effective, and the remaining pertaining to the What, When, Who, and How features of the AMUO. The effectiveness of observation interventions was not only affirmed, but also extended to a wider scope of populations and settings. Greater insight into the necessary information with respect to the demonstration (what) and whether it should be before, after, or during physical practice (when) was obtained. As well, advantages of combining model types (who) and providing control to the learner (how) were reported. Conclusions: While more clarity was brought to certain features of the AMUO that could be used to provide evidence-based guidelines, more research is needed to fully inform practitioners for the effective use of observation interventions.
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Al-Nawaiseh AM, Pritchett RC, Pritchett KK, Bataineh MF, Taifour AM, Bellar D, Schoeff MA, Fox B, Judge A, Judge LW. No significant effect of caffeine on five kilometer running performance after muscle damage. INT J VITAM NUTR RES 2020; 92:357-365. [PMID: 33143547 DOI: 10.1024/0300-9831/a000683] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Caffeine has documented hypoalgesic effects during exercise. However, there is a lack of research focusing on caffeine's potential analgesic effects to ameliorate delayed onset muscle soreness. A placebo controlled randomized cross-over trial was carried out to determine if 5 mg/kg of body weight (mg/kgBW) of caffeine attenuates muscle pain and improves 5 k running performance following delayed onset muscle soreness. Prior to participating, eleven runners (9 male; 2 female; age, 24.5 ± 6.3 years; height, 173.6 ± 7.8 cm; body mass, 66.3 ± 7.5 kg; BMI, 23.18 kg/m2 ± 1.6; VO2max 61.0 ± 6.1 ml/kg/min-1), were asked to discontinue supplement use for 72 hours and abstain from caffeine consumption for 48 hours. Participants performed a 30-minute downhill run on a treadmill set at -10% grade at 70% VO2max to induce delayed onset of muscle soreness. Participants then returned 48 hours after to complete a 5 k time trial run where they consumed either 5 mg/kgBW of caffeine or a placebo. Rate of perceived exertion and heart rate were taken every two minutes during the trial. There was no detectable statistical difference between 5 k performance between caffeine (1074.9 ± 119.7 sec) or placebo (1053.8 ± 86.8 sec) (p = .41). Algometer readings were similar between both treatments for muscle soreness in the rectus femoris (p = .791) and the vastus medialis oblique (p = .371). Muscle soreness ratings were found to be greater in the caffeine condition compared to the placebo condition (p = .030). There was no effect of treatment on rating of perceived exertion between conditions (p = .574). The present study suggests that caffeine is not effective at reducing muscle soreness, rating of perceived exertion, or improving running performance in a time trial in the presence of muscle soreness.
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Affiliation(s)
- Ali M Al-Nawaiseh
- Department of Sport Rehabilitation, The Hashemite University, Az-Zarqa, Jordan
| | | | | | - Mo'ath F Bataineh
- Department of Sport Rehabilitation, The Hashemite University, Az-Zarqa, Jordan
| | - Akef M Taifour
- Department of Sport Rehabilitation, The Hashemite University, Az-Zarqa, Jordan
| | - David Bellar
- University of North Carolina, Charlotte, North Carolina, USA
| | - Makenzie A Schoeff
- Health and Physical Activity Building, Ball State University, Muncie, Indiana, USA
| | - Brian Fox
- Health and Physical Activity Building, Ball State University, Muncie, Indiana, USA
| | - Amy Judge
- Ball Memorial Hospital, Muncie, Indiana, USA
| | - Lawrence W Judge
- Health and Physical Activity Building, Ball State University, Muncie, Indiana, USA
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Mache S, Bernburg M, Groneberg D, Harth V. Neuro-enhancement among German junior physicians: Prevalence, reasons and associations to mental health outcomes and quality of life. Work 2020; 67:285-293. [PMID: 33044210 DOI: 10.3233/wor-203279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Previous research studies have demonstrated that neuro-enhancement, the use of legal or illegal drugs by healthy individuals to improve their job performance, is practiced among employees. Researchers discussed possible reasons for employees to consider the use of substances for neuro-enhancement. OBJECTIVE The aim of this study was to identify the prevalence of usage and motives for practicing neuro-enhancement among a sample of German junior physicians. The secondary objective was to determine associations between neuro-enhancement, mental health outcomes and quality of life. METHODS This cross-sectional study included an online survey to analyze junior physicians' neuro-enhancement stimulant use and their motives for usage (n = 873). Second, mental health outcomes and quality of life were assessed. Descriptive and analytic (Kruskal Wallis test, logistic regression) statistics were obtained. RESULTS Of the 873 junior physicians, 18% reported having used stimulants for neuro- enhancement. 8% of the physicians have taken prescription stimulants (e.g. modafinil) or illicit drugs (e.g. cannabis) at least once in their lifetime. The most common reasons for taking stimulants were to enhance concentration, to relax and to increase alertness. Neuro-enhancement was associated with emotional exhaustion (p < 0.01), lower quality of life (p < 0.05) and work-related stress (p < 0.01). CONCLUSIONS Our study results give an overview on the actual situation regarding frequency and motives for taking performance-enhancing substances. The prevalence rate was low in comparison to current public debates. Decreasing the prevalence of neuro-enhancement among physicians requires the implementation of strategies targeting stress reduction and workload management.
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Affiliation(s)
- Stefanie Mache
- Institute for Occupational and Maritime Medicine (ZfAM), University Medical Center Hamburg-Eppendorf, Seewartenstrasse, Hamburg, Germany.,Institute of Occupational Medicine, Social Medicine and Environmental Medicine, Goethe-University, Theodor-Stern-Kai, Frankfurt am Main, Germany
| | - Monika Bernburg
- Institute of Occupational Medicine, Social Medicine and Environmental Medicine, Goethe-University, Theodor-Stern-Kai, Frankfurt am Main, Germany
| | - David Groneberg
- Institute of Occupational Medicine, Social Medicine and Environmental Medicine, Goethe-University, Theodor-Stern-Kai, Frankfurt am Main, Germany
| | - Volker Harth
- Institute for Occupational and Maritime Medicine (ZfAM), University Medical Center Hamburg-Eppendorf, Seewartenstrasse, Hamburg, Germany
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47
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Wong V, Yamada Y, Bell ZW, Spitz RW, Viana RB, Chatakondi RN, Abe T, Loenneke JP. Postactivation performance enhancement: Does conditioning one arm augment performance in the other? Clin Physiol Funct Imaging 2020; 40:407-414. [PMID: 32869937 DOI: 10.1111/cpf.12659] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 08/12/2020] [Accepted: 08/20/2020] [Indexed: 01/30/2023]
Abstract
The purpose was to determine whether postactivation performance enhancement is specific to the muscle being conditioned or if it is also observed within the homologous muscles of the contralateral limb (after accounting for the warm-up and random error). We also investigated whether this differed based on training status or muscle size. One hundred seven participants (75 untrained; 32 trained) participated in four sessions. Visit 1 included baseline measurements and familiarization. Visits 2-4 included the completion of one of the three experimental conditions: (a) control, (b) same side and (c) crossover completed in a randomized order. The control condition completed all testing except for the conditioning contraction. The same side condition completed the conditioning contraction on the same side as the strength test. The crossover condition completed the conditioning on the arm opposite to the strength test. The variable of interest was the change from baseline in isokinetic strength. Our analysis indicated that of the hypotheses compared, the posterior probabilities (posterior probability of 0.506) favoured the hypothesis that the effect was local and greatest in those who were resistance trained [mean (SD) of 1.4 (2.2) Nm over the control in those resistance trained]. We found no relationship between muscle size and postactivation performance enhancement. In conclusion, there is an influence of training status pertaining to the postactivation performance enhancement effect but no influence from baseline muscle size. It appears unlikely that the effect is due to a systemic mechanism.
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Affiliation(s)
- Vickie Wong
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA
| | - Yujiro Yamada
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA
| | - Zachary W Bell
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA
| | - Robert W Spitz
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA
| | - Ricardo B Viana
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA.,Faculty of Physical Education and Dance, Federal University of Goiás, Goiânia, Brazil
| | - Raksha N Chatakondi
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA
| | - Takashi Abe
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA
| | - Jeremy P Loenneke
- Department of Health, Exercise Science, & Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA
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48
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Wang Y, Liu W, Xin W, Zou T, Zheng X, Li Y, Xie X, Sun X, Yu W, Liu Z, Chen S, Yang J, Guo C. Back-Reflected Performance-Enhanced Flexible Perovskite Photodetectors through Substrate Texturing with Femtosecond Laser. ACS Appl Mater Interfaces 2020; 12:26614-26623. [PMID: 32419457 DOI: 10.1021/acsami.0c04124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Recently, enhancing the performance of flexible perovskite photodetectors through facile and effective means has gained greater attention. In contrast to typical approaches through modifying light-active materials, we present here a simple but effective design by improving light-matter interactions through near-field optical interference on a back-reflected substrate, whose architecture includes a morphologically flat top surface and a backscattering surface textured with micro/nanostructures by the femtosecond laser direct writing. A CH3NH3PbI3 perovskite film and poly(ethylene terephthalate) are selected as the light-active and base materials, respectively. Under a 1 V bias voltage actuation and 532 nm laser irradiation at an intensity of 10 mW cm-2, the flexible device exhibits excellent performance in photoresponsivity (47.1 mA W-1), detectivity (3.7 × 1011 Jones), and on/off ratio (4600). Due to the near-field optical enhancement of the substrate and the strong light-matter interaction, the above performance parameters are enhanced by at least 5 times over a wide spectral range of 220-780 nm. Such enhancement behaviors are independent of active material properties and therefore can be compatible with other operations such as crystalline transformation, doping, and interface modification. Moreover, the alteration of stress distribution on the structured substrate facilitates the bending robustness and stability. These features highlight the potential of back-reflected design in the development of flexible perovskite photoelectric devices, which are especially suitable for large-scale industrial production.
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Affiliation(s)
- Ye Wang
- State Key Laboratory for Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenwei Liu
- The Key Laboratory of Weak Light Nonlinear Photonics Ministry of Education, Teda Applied Physics Institute and School of Physics, Nankai University, Tianjin 300071, China
| | - Wei Xin
- State Key Laboratory for Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Tingting Zou
- State Key Laboratory for Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Zheng
- State Key Laboratory for Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanshuang Li
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Xiuhua Xie
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Xiaojuan Sun
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Weili Yu
- State Key Laboratory for Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Zhibo Liu
- The Key Laboratory of Weak Light Nonlinear Photonics Ministry of Education, Teda Applied Physics Institute and School of Physics, Nankai University, Tianjin 300071, China
| | - Shuqi Chen
- The Key Laboratory of Weak Light Nonlinear Photonics Ministry of Education, Teda Applied Physics Institute and School of Physics, Nankai University, Tianjin 300071, China
| | - Jianjun Yang
- State Key Laboratory for Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Chunlei Guo
- State Key Laboratory for Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- The Institute of Optics, University of Rochester, Rochester, New York 14627, United States
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49
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van Zyl LE, Roll LC, Stander MW, Richter S. Positive Psychological Coaching Definitions and Models: A Systematic Literature Review. Front Psychol 2020; 11:793. [PMID: 32435218 PMCID: PMC7218139 DOI: 10.3389/fpsyg.2020.00793] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/31/2020] [Indexed: 12/03/2022] Open
Abstract
Despite the popularity of the term Positive Psychological Coaching within the literature, there is no consensus as to how it should be defined (framed) or what the components of a positive coaching “model” should include. The aim of this systematic review was to define positive psychological coaching and to construct a clear demarcated positive psychological coaching model based on the literature. A systematic literature review led to the extraction of 2,252 records. All records were screened using specific inclusion/exclusion criteria, which resulted in the exclusion of records based on duplicates (n = 1,232), titles (n = 895), abstracts (n = 78), and criteria violations (n = 23). Twenty-four academic, peer-reviewed publications on positive psychological coaching were included. Data relating to conceptual definitions and coaching models/phases/frameworks were extracted and processed through thematic content analysis. Our results indicate that positive psychological coaching can be defined as a short to medium term professional, collaborative relationship between a client and coach, aimed at the identification, utilization, optimization, and development of personal strengths and resources in order to enhance positive states, traits and behaviors. Utilizing Socratic goal setting and positive psychological evidence-based approaches to facilitate personal growth, optimal functioning, enhanced wellbeing, and the actualization of people's potential. Further, eight critical components of a positive psychological coaching model were identified and discussed. The definition and coaching process identified in this study will provide coaches with a fundamental positive psychological framework for optimizing people's potential.
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Affiliation(s)
- Llewellyn E van Zyl
- Department of Industrial Engineering, University of Eindhoven, Eindhoven, Netherlands.,Optentia Research Focus Area, North-West University (VTC), Vanderbijlpark, South Africa.,Department of Human Resource Management, University of Twente, Enschede, Netherlands.,Institut für Psychologie, Goethe University, Frankfurt, Germany
| | - Lara C Roll
- Optentia Research Focus Area, North-West University (VTC), Vanderbijlpark, South Africa.,Department of Applied Psychology, Lingnan University, Tuen Mun, Hong Kong
| | - Marius W Stander
- Optentia Research Focus Area, North-West University (VTC), Vanderbijlpark, South Africa
| | - Stefanie Richter
- Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
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50
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Seidel-Marzi O, Ragert P. Neurodiagnostics in Sports: Investigating the Athlete's Brain to Augment Performance and Sport-Specific Skills. Front Hum Neurosci 2020; 14:133. [PMID: 32327988 PMCID: PMC7160821 DOI: 10.3389/fnhum.2020.00133] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/23/2020] [Indexed: 12/22/2022] Open
Abstract
Enhancing performance levels of athletes during training and competition is a desired goal in sports. Quantifying training success is typically accompanied by performance diagnostics including the assessment of sports-relevant behavioral and physiological parameters. Even though optimal brain processing is a key factor for augmented motor performance and skill learning, neurodiagnostics is typically not implemented in performance diagnostics of athletes. We propose, that neurodiagnostics via non-invasive brain imaging techniques such as functional near-infrared spectroscopy (fNIRS) will offer novel perspectives to quantify training-induced neuroplasticity and its relation to motor behavior. A better understanding of such a brain-behavior relationship during the execution of sport-specific movements might help to guide training processes and to optimize training outcomes. Furthermore, targeted non-invasive brain stimulation such as transcranial direct current stimulation (tDCS) might help to further enhance training outcomes by modulating brain areas that show training-induced neuroplasticity. However, we strongly suggest that ethical aspects in the use of non-invasive brain stimulation during training and/or competition need to be addressed before neuromodulation can be considered as a performance enhancer in sports.
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Affiliation(s)
- Oliver Seidel-Marzi
- Institute for General Kinesiology and Exercise Science, Faculty of Sport Science, University of Leipzig, Leipzig, Germany.,Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Patrick Ragert
- Institute for General Kinesiology and Exercise Science, Faculty of Sport Science, University of Leipzig, Leipzig, Germany.,Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
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