An analytical method is described for obtaining the precise location of an absorption line and the pressure broadening coefficients due to self-broadening or foreign gas broadening from experimental measurements using a laser operating on a single line near the absorption line. These absorption line characteristics are obtained from the pressure dependence of the transmittance of the laser radiation for the gas of interest, the analysis involving a least squares fit to a family of Lorentz curves. The method includes a computer search for the region of best fit to the Lorentz profile and provides both the values of and errors in the above coefficients. The pressure broadening coefficient obtained is the same as for the more general Voigt curve. The method is applied to the absorption line of vinyl chloride near 27.972 microm and of methane near 3.392 microm and the results compared with a graphical fit to a Voigt profile. The self-broadening coefficients obtained were alpha = 0.15 x 10(-3) +/- 0.97 x 10(-4) cm(-1) Torr(-1) for vinyl chloride and alpha = 0.14 x 10(-3) +/- 0.46 x 10(-4) cm(-1) Torr(-1) for methane. The separation between the helium-neon laser line at 2947.903 cm(-1) and the methane absorption line at 2947.888 +/- 0.015 cm(-1) was found to be 0.21 x 10(-2) +/- 0.15 x 10(-2) cm(-1).
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http://dx.doi.org/10.1364/AO.12.000226 | DOI Listing |
Introduction: Lotilaner ophthalmic solution (0.25%) is the first United States Food and Drug Administration (US FDA)-approved drug for treating Demodex blepharitis. In pivotal trials, it was found to be well tolerated and demonstrated a significant reduction in collarettes and mite density after a 6-week treatment regimen.
View Article and Find Full Text PDFLasers Med Sci
January 2025
Department of Preventive and Restorative Dentistry, Discipline of Endodontics, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil.
Investigate the impact of antimicrobial photodynamic therapy (aPDT) using different photosensitizers (PSs) such as indocyanine green (IG), curcumin (CC), and methylene blue (MB), with or without intracanal application of calcium hydroxide (CH), on the push-out bond strength of glass-fiber posts (GFPs) to intraradicular dentin, the chemical composition of the root substrate, and the sealing of the adhesive interface across different thirds of intraradicular dentin. A total of 112 bovine teeth underwent biomechanical preparation and were divided into eight experimental groups (n = 14 each): Negative control with deionized water; positive control with deionized water + CH; IG group with indocyanine green and infrared laser; IG + CH group; CC group with curcumin and blue LED; CC + CH group; MB group with methylene blue and red laser; and MB + CH group. The push-out bond strength was measured using a universal testing machine (n = 8), and scanning electron microscopy characterized the fracture patterns.
View Article and Find Full Text PDFUrol Res Pract
January 2025
Department of Urology, Ruby Hall Clinic, Pune, India.
Objective: We aimed to evaluate and compare the rise in the temperature for the safety of the ureter and kidney parenchyma when firing the holmium laser and the thulium fiber laser (TFL).
Methods: We performed a laboratory experiment to measure the rise in temperature upon firing holmium laser and a TFL in a 10 cm3 transparent test tube in an outdoor environment and then in a container with normal saline.
Results: In a 10 cc test tube with static water at 25°C, the rise in temperature with holmium and TFL depends on the firing time, keeping power constant.
Cureus
December 2024
Department of Gunapadam, Maria Siddha Medical College and Hospital, Thiruvattar, IND.
Skin tags, medically known as acrochordons, are harmless growths of the epidermis that commonly develop in areas where the skin folds, such as the neck, armpits, or groin. While usually asymptomatic, these lesions can cause discomfort from rubbing or cosmetic issues. They are more prevalent in middle-aged and older individuals and are often correlated with conditions such as obesity, diabetes, and insulin resistance.
View Article and Find Full Text PDFJ Cardiothorac Surg
January 2025
Department of Anesthesiology, Zhongda hospital, Southeast University, No. 87 Dingjiaqiao, Nanjing City, 210009, Jiangsu Province, China.
Monitoring perioperative tissue perfusion is crucial in clinical anesthesia to protect organs and ensure patient safety. Indicators like hemodynamic parameters, tissue metabolism, and microcirculation markers are used for assessment. Studies show intraoperative hypotension negatively impacts outcomes, though blood pressure alone may not reflect tissue perfusion accurately.
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