The impact of prolonged exercise upon right ventricular (RV) function is poorly understood and to date no studies have utilized tissue-Doppler imaging (TDI). Thirty-five marathon runners (age range 18-50 years) volunteered for the study. Two-dimensional, pulsed Doppler, and TDI studies were performed one day before and immediately following race completion. Right and left ventricular (LV) longitudinal TDI myocardial velocities were acquired from the tricuspid annulus and mitral annulus, providing velocity data during systole (S'), early diastole (E'), and late diastole (A'). Transtricuspid and transmitral, early diastolic (E), and late diastolic (A) velocities and ratios were assessed using conventional pulsed-wave Doppler. RV and LV fractional area changes (FAC) were calculated from RV and LV end-diastolic and end-systolic areas recorded from 2D scans in a subsample (n = 23). RV myocardial velocities were unchanged pre-post race in S' (21.1 +/- 2.7 to 21.7 +/- 4.5 cm s(-1), P > 0.05), reduced in E' (23.3 +/- 3.5 to 19.9 +/- 5.3 cm s(-1), P < 0.05), increased in A' (19.1 +/- 3.6 to 23.7 +/- 6.8 cm s(-1), P < 0.05) with a resultant decline in E'/A' (1.28 +/- 0.36 to 0.94 +/- 0.45, P < 0.05). This pattern of data was mirrored in the LV. Similarly both pulsed-Doppler tricuspid and mitral E/A ratios decreased from pre- to postrace (P < 0.05). FAC for the RV and LV were unaltered postrace (P > 0.05). The impact of differing age, finishing time (173-330 min), hemodynamic loading and heart rate upon RV and LV function pre- to postrace was negligible. In conclusion, TDI and 2D data, for both the RV and LV demonstrated little change in systolic function after a marathon race. Conversely, a reduction in diastolic function was observed in both ventricles for which a mechanism has yet to be deduced.
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Symmetry-breaking spin-state transitions in two of three isostructural salts of MnIII spin-crossover cations, [MnIII(3-OMe-5-NO2-sal2323)]+, with heavy anions are reported. The ReO4- salt undergoes two-step spin crossover which is coupled with a re-entrant symmetry-breaking structural phase transition between a high temperature phase (S = 2, C2/c), an intermediate ordered phase (S = 1/S = 2, P21/c), and a low temperature phase (S = 1, C2/c). The AsF6- complex undergoes an abrupt transition between a high temperature phase (S = 2, C2/c) and a low temperature ordered phase (S = 1/S = 2, P-1).
View Article and Find Full Text PDFSoft Matter
January 2025
Department of Applied Mechanics and Biomedical Engineering, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India.
Bioinspired shape-morphing soft magnetic actuators have potential applications in medicine, robotics, and engineering due to their soft body, untethered control, and infinite degrees of freedom. The shape programming of the soft magnetic actuators (consisting of soft ferromagnetic CI particles in a soft matrix) is an involved task, as it requires a moulding process severely limiting the capability to program complex shapes. The current study explores a shape programming technique that architects the particle pattern configuration in the actuator, mimicking the pattern found in the mould-programmed actuator, thereby eliminating the need for a mould and providing a greater capability of programming complex shapes.
View Article and Find Full Text PDFFam Community Health
January 2025
Author Affiliations: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota (Dr Kramer-Kostecka); and School of Kinesiology, University of Minnesota, Minneapolis, Minnesota (Drs Lewis and Barr-Anderson).
Background: Girls' physical activity and healthful eating behaviors decline throughout adolescence. These trajectories may be linked to the underdevelopment of exercise and healthful eater identities. Youth programs might consider prioritizing identity development as an innovative health promotion strategy, especially during the formative preadolescent life stage.
View Article and Find Full Text PDFSmall
January 2025
Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, Delhi, 110016, India.
Crystalline γ-FeO(OH) dominantly possessing ─OH terminals (𝛾-FeO(OH)), polycrystalline γ-FeO(OH) containing multiple ─O, ─OH, and Fe terminals (𝛾-FeO(OH)), and α-FeO majorly containing ─O surface terminals are used as electrocatalysts to study the effect of surface terminals on electrocatalytic nitrate reduction reaction (eNORR) selectivity and stabilization of reaction intermediates. Brunauer-Emmett-Teller analysis and electrochemically determined surface area suggest a high active surface area of 117.79 m g (ECSA: 0.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, P. R. China.
Membrane distillation (MD) efficiently desalinizes and treats high-salinity water as well as addresses the challenges in handling concentrated brines and wastewater. However, silica scaling impeded the effectiveness of MD for treating hypersaline water and wastewater. Herein, the effects of humic acid (HA) on silica scaling behavior during MD are systematically investigated.
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