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Objectives: To examine whether gender or side of the boat influenced shape characteristics of the force-angle profile in on-water single sculling.
Design: Cross-sectional study design.
Methods: Bivariate functional principal components analysis (bfPCA) was applied to force-angle data to identify the main modes of variance in curves of forty highly skilled male and female rowers (national and international level), rowing at 32 strokes per minute in a single scull boat.
Results: Separate discriminant function analyses for each side of the boat showed strong classification of rowers for gender. Force application close to (or closely around) the perpendicular oar position was demonstrated to be different between genders. A mixed ANOVA exploring gender, boat side and their interaction revealed that bow and stroke side forces were also statistically different from each other independently of gender. A main effect, independent of side of the boat, was also present for gender and no interaction was found between gender and boat side. Bow side forces seemingly acted as a driver of power and peak force production, while stroke side forces may have acted as a mediator of propulsive forces with an additional potential role in steering due to known asymmetrical offsets in boat rigging.
Conclusions: Results demonstrate that propulsive force differences according to gender and boat-side are evident and must be acknowledged and accounted for before force-angle graphs are explored relative to performance measures.
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http://dx.doi.org/10.1016/j.jsams.2017.08.010 | DOI Listing |
Sci Rep
August 2025
College of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China.
An array of micro-ramp vortex generators (MRVGs) is deployed on the bottom of the ship's hull just before the inlet, aiming to mitigate flow separation on the ramp wall at low inlet velocity ratios (IVR). Four parameters, including height, wedge angle, side length, and spanwise spacing, were analyzed using the numerical methods. Through parametric screening, the optimal height ranges from 20 to 40% of the hull boundary layer thickness upstream of the inlet, while wedge angle and length have negligible effects.
View Article and Find Full Text PDFCommun Eng
March 2025
Jilin University, College of Instrumentation and Electrical Engineering, Changchun, China.
The control and manipulation of waves in optical and/or acoustic science and engineering are widespread. Recently, despite reported studies on high frequency acoustic waves via time modulated media, none of these approaches has demonstrated success with broadband frequency exceeding that of the mechanical system, and all of them were not able to emit ultralow frequency waves. There are both fundamental and practical issues.
View Article and Find Full Text PDFJ Racial Ethn Health Disparities
March 2025
Tilman J. Fertitta Family College of Medicine, The University of Houston, 5055 Medical Circle, Houston, TX, USA.
Background: Due to limited research on Asian Americans and COVID-19, we investigated the perspectives of Vietnamese Americans regarding COVID-19 vaccine acceptance, trusted sources of information, and pandemic-related challenges.
Methods: Vietnamese American adult residents in Texas were recruited between September 2021 through March 2022 to complete the NIH CEAL Common Survey 2 electronically in English or Vietnamese, which contains 23 questions about social determinants of health, information, trust, risk perception, testing and disease control, COVID-19 vaccination, and demographics. We analyzed data using bivariate logistic or linear regression models.
Acta Crystallogr C Struct Chem
March 2025
Departamento de Química, Universidad de Oriente, Cumaná, Estado Sucre, Venezuela.
The first X-ray crystal structure is reported for [dihydrobis(pyrazol-1-yl)borato-κN,N']tris(tetrahydrofuran-κO)magnesium(II) tetrabenzylborate, [Mg(CHBN)(CHO)][B(CH))], (I), which was obtained by reacting crude [K(CHBN)] with an equimolar amount of (PhCH)MgCl in tetrahydrofuran at room temperature and was isolated as a side product. The crystal structure analysis reveals the existence of a pronounced boat-shaped central Mg(N-N)B moiety with a weak pseudo-axial B-H..
View Article and Find Full Text PDFTrop Med Health
January 2025
Laboratory of Hygiene and Epidemiology, Faculty of Medicine, University of Thessaly, 22 Papakyriazi Street, 41222, Larissa, Thessaly, Greece.
Background: With various infectious disease risks to passenger ship travellers, guidance for infectious disease prevention, mitigation and management (PMM) exists. Emerging infections and emergencies necessitate updated, context-specific guidelines and practices. New evidence for infection PMM must be translated into guidance for governmental authorities and the passenger ship industry.
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