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Effects of speed, agility, and quickness training on athletic performance: a systematic review and meta-analysis
Get PDFBackground: Previous studies have demonstrated the effects of SAQ training on sprint, change-of-direction, and jump performance in soccer players. However, further research is needed to assess its broader impact on different athletic populations and performance metrics. This study aims to expand the existing evidence by incorporating a wider range of outcomes and providing a more comprehensive analysis of SAQ training effects. Methods: A thorough search of databases, including Web of Science Core, SPORTDiscus, PubMed, and SCOPUS, was conducted, with data up to July 2024. The PEDro scale assessed study quality and RevMan 5.3 evaluated bias risk. Effect sizes (ES) were calculated from means and standard deviations, with heterogeneity assessed using the I² statistic. Publication bias was evaluated using an extended Egger test. Results: Eleven RCTs involving 499 healthy athletes from sports such as soccer, basketball, tennis, and handball met the inclusion criteria. The SAQ interventions lasted between 4 and 12 weeks, with a frequency of two to three sessions per week. The analysis revealed significant improvements in 5-meter sprint (ES = 0.63, p 60 min: ES = 0.24; p = 0.059). Conclusions: SAQ training effectively enhances sprint performance, COD ability, reaction time, lower limb strength, and flexibility, with effect sizes ranging from small to moderate. The findings suggest that shorter training durations (≤ 60 min) may be more beneficial for improving COD performance, although this effect did not reach statistical significance. Further trials are recommended to determine the optimal training dosage, along with high-quality studies covering a broader range of sports, particularly in athletes aged 14 to 18
Evaluation of macro and meiobenthic community structure and distribution in the hybrid ocean thermal energy conversion discharge area of Port Dickson
Get PDFOver the past two decades, the technology underlying Hybrid Ocean Thermal Energy Conversion (H-OTEC) power plants have progressively matured. These advancements position H-OTEC as a promising alternative energy source with significant potential to replace traditional power plants. The cold discharge from H-OTEC Pilot Plants reduces the temperature of receiving water bodies, thereby directly or indirectly impacting the marine ecological environment. A one-year study was conducted around a pilot-stage 1.0 MW H-OTEC Pilot Plant in Port Dickson to investigate the effects of cold discharge on macro- and meiobenthic communities across different seasons. Apart from the water temperature within a 5-meter range affected by the H-OTEC cold discharge, the impact on other water quality indicators is negligible. A total of 22 macrobenthic species belonging to 4 phyla and meiobenthic organisms belonging to 9 taxa were identified across 15 sampling points. This study demonstrated that cold emissions had a limited impact on the abundance and community structure of benthic organisms across different seasons. The abundance of benthic organisms exhibited a significant increase in Inter-monsoon, followed by a significant decrease in Dry season. Moreover, there was a positive correlation observed between the abundance of benthic organisms and the content of water temperature, conductivity, gavel, sediment pigments and total organic matter. This study identified significant seasonal variations in the structure of both macro- and meio-benthic communities. Specifically, Umbonium vestiarium and other gastropoda were the dominant taxa and primary contributors to the observed significant changes in the structure of macro- and meio-benthic communities, respectively. Nevertheless, further study with a higher discharge volume of the outfall is crucial to assist in the outfall pipe placement of the mega-scale OTEC electricity plant. This study provided crucial insights into the ecological impacts of cold emissions from H-OTEC Pilot Plants in tropical coastal areas
Lexical richness in Chinese university students’ EFL writing: a corpus-based comparison
Get PDFLexical richness (LR) is widely recognized as a key indicator of proficiency among learners of English as a foreign language (EFL). With the rise of numerous software tools capable of automatically measuring LR in recent years, LR has received increasing attention as a focal area of research in the context of Chinese university students’ (CUSs) EFL writing. However, these quantitative studies often reduce LR to numerical values, lacking a comparative framework for evaluating lexical proficiency in CUSs’ EFL writing. This study adopts Foster and Tavakoli’s approach, using native language proficiency as a comparative baseline. It examines LR in CUSs’ EFL writing compared to English as a native language (ENL) writing, utilizing corpus-based data from SWECCL 2.0 and LOCNESS across three dimensions: lexical density, sophistication, and variation. The results of Mann–Whitney U tests reveal that CUSs’ lexical density in English writing is comparable to that of ENL writing, which may be attributed to the influence of their native language, Chinese. However, they exhibit lower mean ranks of lexical sophistication and variation, showing distinct patterns compared to ENL writing. These disparities may be attributed to factors like limited exposure to advanced vocabulary and cultural attitudes toward risk-taking in language use. Practical pedagogical implications include enhancing exposure to low-frequency vocabulary through enriched input, incorporating contextualized vocabulary instruction, and providing feedback-driven writing tasks that promote lexical variation. This study contributes to the understanding of LR in EFL contexts by emphasizing the need for targeted instructional strategies and offering insights into improving lexical proficiency among EFL learners
Dual solutions of hybrid nanofluid flow past a permeable melting shrinking sheet with higher-order slips, shape factor and viscous dissipation effect
No full textPurpose: This paper aims to explore dual solutions for the flow of a hybrid nanofluid over a permeable melting stretching/shrinking sheet with nanoparticle shape factor, second-order velocity slip conditions and viscous dissipation. The hybrid nanofluid is formulated by dispersing alumina (Al2O3) and copper (Cu) nanoparticles into water (H2O). Design/methodology/approach: The governing partial differential equations (PDEs) are first reduced to a system of ordinary differential equations (ODEs) using a mathematical method of similarity transformation technique. These ODEs are then numerically solved through MATLAB’s bvp4c solver. Findings: Key parameters such as slip parameter, melting parameter, suction parameter, shrinking parameter and Eckert number are examined. The results reveal the existence of two distinct solutions (upper and lower branches) for the transformed ODEs when considering the shrinking parameter. Increasing value of Cu-volume fraction and the second-order velocity slip enhances boundary layer thicknesses, whereas the heat transfer rate diminishes with rising melting and suction parameters. These numerical results are illustrated through various figures and tables. Additionally, a stability analysis is performed and confirms the upper branch is stable and practical, while the lower branch is unstable. Practical implications: The analysis of hybrid nanofluid flow over a shrinking surface has practical significance with applications in processes such as solar thermal management systems, automotive cooling systems, sedimentation, microelectronic cooling or centrifugal separation of particles. Both steady and unsteady hybrid nanofluid flows are relevant in these contexts. Originality/value: While the study of hybrid nanofluid flow is well-documented, research focusing on the shrinking flow case with specific parameters in our study is still relatively scarce. This paper contributes to obtaining dual solutions specifically for the shrinking case, which has been less frequently addressed
Assessment of Opuntia ficus-indica supplementation on enhancing antioxidant levels
Get PDFOpuntia ficus-indica (OFi) is a major fruit source prevalent in semiarid and arid regions across various countries worldwide. It is widely recognised for its potential health benefits; however, most studies investigating its effects have been limited to pre-clinical models, highlighting the need for further validation through clinical trials. This study aimed to evaluate the effectiveness of OFi supplementation in enhancing antioxidant levels. Fifty healthy participants, aged 18 years and older, including males and females, received a daily OFi supplement of 1500 mg for 3 months. These findings revealed a significant 48.1% increase in salivary total antioxidant capacity (TAC) (P < 0.001), indicating improved antioxidant activity. Simultaneously, oxidative stress biomarkers showed substantial reductions: malondialdehyde (MDA) decreased by 28.3%, nitrotyrosine (3-NT) decreased by 51.5%, and 8-hydroxy-2’-deoxyguanosine (8-OHdG) decreased by 59.8% (P < 0.001). Furthermore, participants reported a 20.1% improvement (P < 0.001) in Visual Analogue Scales (VAS), reflecting a notable enhancement in overall well-being. In conclusion, OFi exhibited promising efficacy in elevating antioxidant levels and mitigating oxidative stress. These findings suggest its potential as an adjuvant therapy for managing chronic conditions associated with oxidative stress
Evaluation of different seed dormancy breaking methods including enzymatic assays for germination improvement in oil palm (Elaeis guineensis Jacq.)
Get PDFThe oil palm (Elaeis guineensis) is propagated by seeds for establishment in nurseries and commercial plantations. The seed is naturally dormant; thus, heat treatment is commercially used to alleviate this problem. This study evaluated eight seed dormancy breaking methods (operculum removal, 60 days storage, 60 days 40°C heat treatment, 120 days storage, 60 days storage + 40°C heat treatment, 180 days storage, 120 days storage + 40°C heat treatment and control) on seed germination, based on physical, morphological and physiological dormancy characteristics. Imbibition test indicated that less than 7% mass increment was recorded in all treatments. Germination of more than 82% was obtained for all heat-treated seeds with less than 13 days of mean germination time. The embryo was fully developed at 20 weeks after pollination, but applying heat treatment has accelerated its growth. The heat and storage treatments cause up to 36% reduction in peroxidase and 13% in catalase activities, with 9% (endosperm) and 26% (embryo) increment of α-amylase. It can be suggested that oil palm seeds exhibit a non-deep physiological dormancy, with heat treatment of 40°C as the most effective and practical dormancy-breaking method for commercial seed production
Investigation of flexural mechanical and creep properties of sleeve reinforced pultruded glass fibre reinforced polymer composite for crossarm application
Get PDFPultruded glass fiber-reinforced polymer (PGFRP) composites are innovative materials used in high-rise transmission towers that undergo failure due to long-term static loading phenomenon. This research focuses on retrofitting PGFRP composite cross-arms with plug-in type sleeve reinforcements by employing a three-point bending (3 PB) test to analyze the cross-arm’s elastic properties, flexural creep response, and deflection behaviour. The addition of the sleeve retrofit significantly improved the load–deflection behaviour and long-term creep resistance, by 45.30% and 47.10%, respectively. Findley’s power law model was used to accurately predict the viscoelastic response of the structure, revealing that the virgin cross-arm experienced a 75% drop in elastic modulus, while the sleeve-reinforced cross-arm saw only a 34% decrease indicating over 40% improvement in the cross-arm’s ability to resist deformation over extended periods. Additionally, the overall reduction factor improved by 0.51 in contrast to virgin cross-arm. The sleeve-reinforced cross-arm showed reduced deflection, better creep resistance, increased bending strength, and a longer theoretical lifespan. Predictions indicate that the improved cross-arm surpasses the current one in long-term mechanical performance
Coherent control of anisotropic SPPs in a symmetric double-layer metal/uniaxial dielectric structure
Get PDFWe investigate the coherent control of anisotropic surface plasmon polaritons (SPPs) in a symmetric double-layer metal/uniaxial dielectric structure. The directional anisotropy introduced by the uniaxial dielectric enables tunable SPP dispersion, absorption, and propagation characteristics through an external control field. We analyze reflection and transmission spectra, dispersion relations, propagation lengths, and the scattering matrix eigenmodes. Our results reveal strong modulation of SPP wavelength and enhanced propagation length with varying control field strength and metal layer composition. Remarkably, we observe coherent perfect absorption for both symmetric and anti-symmetric modes, an effect not commonly realized in such layered anisotropic systems. This work introduces a novel platform for actively tunable nanoplasmonic devices, with potential applications in waveguiding, sensing, and plasmonic circuitry
