The sphericity and wall-thickness uniformity requirements of direct-drive inertial-fusion targets are of the order of less than 1%. These shells display self-interference patterns (SIP's) when irradiated with a spatially incoherent, narrow-bandwidth light source and viewed with a compound microscope. These patterns are distinct concentric fringes when the target is uniform, whereas faint, distorted, or discontinuous fringes indicate a nonuniform target. We determined the wall thickness to within +/-0.5 microm by counting the number of fringes in the SIP, independent of the outside diameter. Thickness uniformity is verified to an accuracy better than 0.05 microm. The wall thickness of gas-filled targets can be determined to this accuracy without knowledge of the type of gas or its pressure. The SIP fringe technique is used to select polymer shells typically of 800- to 1000-microm diameter and 5- to 12-microm wall thickness. The fringe locations have been modeled by use of ray tracing and agree well with actual measurements of well-characterized shells. Details of the formation of the SIP fringes, a theoretical model, and the method used for quantitative measurement of the shell-wall thickness with the SIP are presented with validation examples.
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http://dx.doi.org/10.1364/ao.38.005365 | DOI Listing |
Biomed Phys Eng Express
January 2025
Physics and Applied Mathematics, Pakistan Institute of Engineering and Applied Sciences, Qau, Islamabad, Islamabad, 44000, PAKISTAN.
The current study investigated the geometry, design and solid angle impacts on full energy peak efficiency (FEPE) of NaI(Tl) detectors for a line source. A line source is fabricated using 99mTc solution filled in a borosilicate glass tube of inner diameter 3 mm, tube wall thickness 2.5 mm and length 12.
View Article and Find Full Text PDFJ Periodontol
January 2025
Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou, China.
Background: The clinical evidence about alveolar ridge changes following molar extraction and how the alveolar bone morphology influences the ridge dimensional changes remains limited.
Methods: A total of 192 patients with 199 molar extractions were included in this retrospective study. Cone-beam computed tomography (CBCT) images of patients were obtained 0-3 months pre extraction and 6-12 months post extraction.
Rev Cardiovasc Med
January 2025
Department of Echocardiography and Cardiology, The First People's Hospital of Changzhou, 213003 Changzhou, Jiangsu, China.
Background: This article focuses on the effect of body mass index (BMI) on cardiac structure and function in cases with non-valvular atrial fibrillation (NVAF). Only a few articles have investigated the relationship between BMI and the incidence of left atrial thrombus (LAT) or spontaneous echo contrast (SEC) in cases with NVAF.
Methods: This single-center retrospective study was conducted at The First People's Hospital of Changzhou.
Cureus
December 2024
Obstetrics and Gynecology, Marunouchi Hospital, Matsumoto, JPN.
Malignant transformation is a rare complication of ovarian mature cystic teratoma that occurs in 1-3% of cases. We herein report a case of squamous cell carcinoma originating from mature cystic teratoma of the ovary diagnosed 10 years after initial tumor detection. A 69-year-old woman presented to the Department of Internal Medicine with a seven-month history of abdominal fullness.
View Article and Find Full Text PDFZhonghua Yi Xue Za Zhi
January 2025
Department of Urology, Henan Joint International Pediatric Urodynamic Laboratory, the First Affiliated Hospital of Zhengzhou University, Zhengzhou450002, China.
To comprehensively evaluate the structure and function of the bladder wall in children using multi-modal ultrasound (MMU). A total of 110 children without urinary symptoms admitted to the First Affiliated Hospital of Zhengzhou University from January 2022 to June 2023 were included prospectively. MMU was performed and the vesical volume (VV), bladder wall thickness (BWT), shear wave velocity (SWV) of the anterior wall, resistance index (RI) and vascularization index (VI) were measured in the filled and emptied bladder respectively, and the ultrasound bladder compliance (UBC) was also calculated.
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