The relation of leg, shoulder, and grip strength to ball speed in the tennis serve was investigated. For 15 collegiate male tennis players, leg and shoulder strength were measured using a Lido Active isokinetic dynamometer, grip strength with a handgrip dynamometer, and ball speed with a radar gun. Regression analysis showed no significant (p<.05) relationship among the strength variables and ball speed. Results were explained in terms of strength not being the only factor involved in producing ball speed during the tennis serve.
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http://dx.doi.org/10.2466/pms.2003.97.3.867 | DOI Listing |
Phys Med Biol
January 2025
Electrical and Computer Engineering, University of Massachusetts Lowell, Ball Hall, 1 University Ave, Lowell, Massachusetts, 01854, UNITED STATES.
Objective: X-ray photon-counting detectors (PCDs) have recently gained popularity due to their capabilities in energy discrimination power, noise suppression, and resolution refinement. The latest extremity photon-counting computed tomography (PCCT) scanner leverages these advantages for tissue characterization, material decomposition, beam hardening correction, and metal artifact reduction. However, technical challenges such as charge splitting and pulse pileup can distort the energy spectrum and compromise image quality.
View Article and Find Full Text PDFSci Rep
January 2025
Minerals Beneficiation and Agglomeration Department, Minerals Technology Institute, Central Metallurgical Research & Development Institute (CMRDI), P.O. Box 87, Helwan, Cairo, 11722, Egypt.
Fine grinding using a stirred ball mill can enhance ore liberation but incurs high energy consumption, which can be minimized by optimizing operating conditions. This study explores the impact of key operational parameters-grinding time, stirrer tip speed, solid concentration, and feed size-on grinding efficiency, evaluated using specific energy inputs, in stirred milling of Egyptian copper ore. The particle size distribution (PSD) of ground products was simulated using the Gates-Gaudin-Schuhmann model (GGS) and the Rosin-Rammler-Benne (RRB) function.
View Article and Find Full Text PDFAnal Chem
January 2025
ICGM, Univ. Montpellier, CNRS, ENSCM, 34000 Montpellier, France.
In this contribution, we apply our newly developed ball-milling platform, which combines Raman spectroscopy and thermal (IR) imaging, as well as acoustic and high-speed optical video recordings, to the synthesis and transformation of citric acid-isonicotinamide (1:2) cocrystal polymorphs in transparent PMMA jars. Particularly, we demonstrate how Raman, temperature, acoustic, and video data are complementary and enable detection and connection of chemical and physical events happening during ball-milling in a time-resolved manner. Importantly, we show that the formation of the three cocrystal polymorphs can be detected through acoustic analyses solely.
View Article and Find Full Text PDFInd Eng Chem Res
January 2025
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.
This work presents the scale-up of room-temperature mechanochemical synthesis of nanocorundum (high-surface-area α-AlO) from boehmite (γ-AlOOH). This transformation on the 1 g scale using a laboratory shaker mill had previously been reported. High-energy Simoloyer ball mills equipped with milling chambers of sizes ranging from 1 to 20 L were used to scale up the mechanochemical nanocorundum synthesis to the 50 g to 1 kg scale, which paves the way to further increase batch size.
View Article and Find Full Text PDFJ Biomech
January 2025
Stevens Institute of Technology, Hoboken, NJ, USA. Electronic address:
This study revealed how high school pitchers generated momenta during fastballs and changeups at a whole-body level. Baseball pitchers control ground reaction forces to generate whole-body momentum. Pitchers attempt to throw as fast and accurately as possible during fastballs but also need to throw off-speed pitches like changeups to deceive batters.
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