A massless acoustic source is proposed for scale model work. This source is generated by focusing a pulsed laser beam to rapidly heat the air at the focal point. This produces an expanding small plasma ball which generates a sonic impulse that may be used as an acoustic point source. Repeatability, frequency response, and directivity of the source were measured to show that it can serve as a massless point source. The impulse response of a rectangular space was determined using this type of source. A good match was found between the predicted and the measured impulse responses of the space.
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http://dx.doi.org/10.1121/1.4793566 | DOI Listing |
Am J Sports Med
January 2025
Section of Young Adult Hip Surgery, Division of Sports Medicine, Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois, USA.
Background: Many studies have examined the prevalence of acetabular version (AV) and femoral version (FV) abnormalities and their effect on patient-reported outcomes (PROs) after hip arthroscopy for femoroacetabular impingement syndrome (FAIS), but few have explored the prevalence and influence of combined version (CV) abnormalities.
Purpose: To (1) describe the distribution of AV, FV, and CV in the largest cohort to date and (2) determine the relationship between AV, FV, and CV and PROs after hip arthroscopy for FAIS.
Study Design: Cohort study; Level of evidence, 3.
Sci Rep
January 2025
College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
The scientific establishment of the Ecological Security Pattern (ESP) is crucial for fostering the synergistic development of ecological and recreational functions, thereby enhancing urban ecological protection, recreational development, and sustainable growth. This study aimed to propose a novel method of constructing ESP considering both ecological and recreational functions, and to reconstruct ESP by weighing the relationship between ecological protection and recreational development. Utilizing Fuzhou City as a case study, a comprehensive application of methodologies including Morphological Spatial Pattern Analysis (MSPA), landscape connectivity analysis, ArcGIS spatial analysis, social network analysis (SNA), and circuit theory is employed to develop both the ESP and the Recreational Spatial Pattern (RSP).
View Article and Find Full Text PDFInt Urogynecol J
January 2025
Department of Urology, Hasheminejad Kidney Center, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Introduction And Hypothesis: This study was aimed at evaluating the therapeutic effects of a modified intravesical botulinum toxin injection technique (fewer injection sites under local anesthesia), in comparison with the conventional technique for patients with idiopathic detrusor overactivity, considering the urodynamic parameters.
Methods: In this double-blinded randomized clinical trial, 78 adult females with idiopathic detrusor overactivity were divided into two groups: conventional and modified groups. In the conventional method, patients received intradetrusor botulinum toxin injection at 20 sites under general or spinal anesthesia in a trigone-sparing fashion.
J Environ Manage
January 2025
School of the Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083, China.
The effectiveness of protected areas in mitigating human impacts remains uncertain due to limited in-situ data; however, atmospheric micropollutant deposition in alpine lakes may provide a quantitative approach to evaluate anthropogenic pressures and threats. In this study, the temporal changes of polycyclic aromatic hydrocarbons (PAHs) inside/outside the Siling Co protected area, Tibet were reconstructed. The varying anthropogenic impact history suggested that, unlike the dominance of residential activities (i.
View Article and Find Full Text PDFAm J Sports Med
January 2025
Department of Sports Medicine, Peking University Third Hospital; Institute of Sports Medicine of Peking University; Beijing Key Laboratory of Sports Injuries, Beijing, China.
Background: There is a lack of evidence and continuous debate on whether femoral tunnel displacement substantially influences the clinical efficacy of medial patellofemoral ligament reconstruction (MPFL-R) in addressing recurrent patellar dislocation.
Purpose: To investigate possible associations between inaccurate femoral tunnel placement during MPFL-R and clinical outcomes, with a specific focus on proximal tunnel malpositioning.
Study Design: Cohort study; Level of evidence, 3.
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