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In the present work, a non-intrusive diagnostic technique known as molecular tagging velocimetry was used to collect quantitative freestream velocity measurements in the Mach 7 Ludwieg Tube Wind Tunnel located at The University of Texas at San Antonio. This laser-based diagnostic technique used a single Nd:YAG 4 harmonic laserline to excite acetone molecules seeded in the flow field. From the resulting emitted light, mean and instantaneous velocity profiles in the hypersonic freestream flow and facility boundary layer were measured. Uncertainty in the velocity measurements for individual test runs is estimated at ≤ 8% while overall 1D freestream mean velocity measurements were recorded with ±2.4% (± 21 m/s) accuracy. The effect of acetone seeding on the speed of sound was also quantified.
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http://dx.doi.org/10.1364/OE.474841 | DOI Listing |
Rev Cardiovasc Med
August 2025
Department of Nephrology, Akron Nephrology Associates at Cleveland Clinic Akron General Medical Center, Akron, OH 44302, USA.
Cardiovascular assessments in children and adolescents with hypertension are essential for detecting early signs of organ damage and guiding timely interventions. The pathophysiology of pediatric hypertension involves a complex interplay of arterial stiffness, endothelial dysfunction, metabolic disturbances, activation of the renin-angiotensin-aldosterone system, and immune dysregulation. These mechanisms collectively contribute to target organ damage, particularly in the cardiovascular system.
View Article and Find Full Text PDFDrug Des Devel Ther
September 2025
Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, People's Republic of China.
Purpose: Spinal anesthesia-induced hypotension can cause detrimental effects on both the mother and the fetus, and it remains a significant concern in obstetric anesthesia. The use of vasopressors is considered the most reliable and effective approach. Previous studies have shown that norepinephrine appears to be superior to phenylephrine in maintaining maternal heart rate and cardiac output.
View Article and Find Full Text PDFInt J Sports Physiol Perform
September 2025
Department of Physical Education and Sport Sciences, National Taiwan Normal University, Taipei, Taiwan.
Purpose: This study explored the acute physiological effects of different eccentric tempos, explosive speed (EXP), volitional speed, and 4-second tempo during 5 sets of velocity-based squat training.
Methods: Twelve healthy males performed parallel squats under 3 eccentric conditions using a randomized crossover design. Each session included 5 sets at a relative load, initiated with a concentric mean velocity of 0.
Turk J Pediatr
September 2025
Department of Cardiorespiratory Physiotherapy and Rehabilitation, Faculty of Physical Therapy and Rehabilitation, Hacettepe University, Ankara, Türkiye.
Background: Vascular changes are observed in children with cystic fibrosis (cwCF), and gender-specific differences may impact arterial stiffness. We aimed to compare arterial stiffness and clinical parameters based on gender in cwCF and to determine the factors affecting arterial stiffness in cwCF.
Methods: Fifty-eight cwCF were included.
IEEE Trans Med Imaging
September 2025
In ultrasound imaging, propagation of an acoustic wavefront through heterogeneous media causes phase aberrations that degrade the coherence of the reflected wavefront, leading to reduced image resolution and contrast. Adaptive imaging techniques attempt to correct this phase aberration and restore coherence, leading to improved focusing of the image. We propose an autofocusing paradigm for aberration correction in ultrasound imaging by fitting an acoustic velocity field to pressure measurements, via optimization of the common midpoint phase error (CMPE), using a straight-ray wave propagation model for beamforming in diffusely scattering media.
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