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Beach volleyball (BV) is an intermittent sport characterised by short-duration and highly demanding activities with low intensity periods. Establishing if players' jump ability is influenced by sand granulometry is a useful information for sport scientists, coaches and players. This study aimed to assess the possible differences in the kinetics parameters of the vertical jump on different types of sand performed by BV players. Twelve elite female players performed six countermovement jumps (CMJs) in three different surface conditions (fine sand, reference, coarse sand) in a random counterbalanced order (216 jumps). A generalised mixed model approach detected differences for CMJ model in total duration (p: 0.016), eccentric phase duration (p: 0.007), concentric phase duration (p: 0.011), time to peak power (p: < 0.001), time to peak force (p: 0.014), maximum rate force development concentric phase (p: 0.004), maximum velocity (p: 0.028) and peak power eccentric (p: 0.018). Coarse sand decreases the time spent jumping compared to fine sand, without a penalty to jump height. Coaches and athletes should take this information into account to enhance their understanding of practice strategies and game conditions. One might anticipate a faster pace in games played on coarse sand and a slower pace on fine sand.
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http://dx.doi.org/10.1080/14763141.2024.2394803 | DOI Listing |
Environ Res
September 2025
Advanced Institute of Information Technology, Peking University, Hangzhou 311215, China; National Institute of Health Data Science, Peking University, Beijing 100191, China; Renal Division, Department of Medicine, Peking University First Hospital; Peking University Institute of Nephrology, Beijing 1
Objective: The impact of desert-originated dust has been underestimated in fine particulate matters (PM)-related disease burden studies. This study aimed to assess the association of long-term dust PM exposure and all-cause mortality among older adults in China.
Methods: A cohort study using electronic health records (2010-2020) across Weinan, a city in northwest China, which experiences persistently high PM levels and frequent sand and dust storms, included 1,553,724 adults aged ≥45 years.
J Contam Hydrol
September 2025
School of Marine Sciences, Sun Yat-sen University, 135 Xin'gang RD.W., Guangzhou 510275, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China. Electronic address:
We systematically investigated DNEs throughout imbibition processes, specifically evaluating: (1) the temporal correspondence between DNE development and changes in water saturation/capillary pressure, and (2) the dominant factors governing DNE magnitude during imbibition. The signal drift during extended testing, and the gravitational effect on both the capillary pressure and water saturation were eliminated. The results indicate that, when water saturation was below a threshold value (∼0.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
September 2025
Department of Materials Science and Engineering, Missouri University of Science and Technology, 1400 N. Bishop, Rolla, MO, 65409, USA.
Plastic waste poses environmental and health risks, highlighting the need for sustainable reuse in construction. This study introduces a novel solution to plastic waste utilization by: (1) developing rheological testing equipment from plastic using 3D printing technology, and (2) enhancing the rheological performance of self-compacting mortar (SCM) with 3D-printed plastic fine aggregates (3DPFA). SCM mixtures incorporating 5%, 10%, 15%, and 20% 3DPFA as a replacement for natural sand were prepared and tested to evaluate fresh, mechanical, and thermal properties through mini-slump flow, T20 spread time, J-ring flow, V-funnel, compressive strength, UPV, and thermal conductivity tests.
View Article and Find Full Text PDFSci Prog
September 2025
Department of Construction and Building Engineering, High Institute of Engineering, October 6 City, Egypt.
The solid waste generated by the waste sanitary ware (WSW) sector is of considerable magnitude on a global scale. Recycling ceramic waste is an essential practice that ensures its proper disposal. Therefore, the objective of this research endeavor was to investigate the effects of replacing sand with WSW on different characteristics of foamed concrete (FC), such as its thermal properties, transportability, freshness, and mechanical strengths.
View Article and Find Full Text PDFSci Total Environ
August 2025
Space Information and Big Earth Data Research Center, School of Computer Science and Technology, Qingdao University, Qingdao 266071, China; Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China. Electronic address: zhang
Land cover (LC) change is a crucial indicator reflecting the interaction between human activities and ecological environment. In semi-arid and arid regions like the Mongolian Plateau (MP), LC change analysis is particularly meaningful in shaping biodiversity, agricultural and grassland environment, and climate regulation, but long-term spatiotemporal dynamics of LC change in MP remain uncertain. This study employed an intensity analysis approach to investigate LC changes over the MP from 1990 to 2020 by using a fine-scale 30 m resolution land cover dataset generated from multi-source satellite images.
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