We report the implementation of a one-dimensional random laser based on an Er/Ge co-doped single-mode fiber with randomly spaced Bragg gratings. The random grating array forms a complex cavity with high quality factor resonances in the range of gain wavelengths centered around 1535.5 nm. The reflection spectra of the grating array and the emission spectra of the laser are investigated for different numbers of gratings. The experimental results are compared qualitatively with numerical simulations of the light propagation in one-dimensional Bragg grating arrays based on a transfer matrix method. The system is pumped at 980 nm and the experimentally observed output radiation presents a typical laser threshold behavior as a function of the pump power. We find that the laser output contains several competing spectral modes.
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http://dx.doi.org/10.1364/oe.17.000395 | DOI Listing |
Comput Biol Med
January 2025
Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL, 32610, United States; Department of Medicine, University of Florida, Gainesville, FL, 32610, United States; Department of Health Outcomes and Biomedical Informatics, University of Florida, Gainesville, FL, 32610, United States; Intelligent Clinical Care Center, University of Florida, Gainesville, FL, 32610, United States. Electronic address:
Retinal image registration is essential for monitoring eye diseases and planning treatments, yet it remains challenging due to large deformations, minimal overlap, and varying image quality. To address these challenges, we propose RetinaRegNet, a multi-stage image registration model with zero-shot generalizability across multiple retinal imaging modalities. RetinaRegNet begins by extracting image features using a pretrained latent diffusion model.
View Article and Find Full Text PDFAnal Chem
January 2025
College of Chemistry and Material Science, Northwest University, Xi'an 710127, China.
With rapid, energy-intensive, and coal-fueled economic growth, global air quality is deteriorating, and particulate matter pollution has emerged as one of the major public health problems worldwide. It is extremely urgent to achieve carbon emission reduction and air pollution prevention and control, aiming at the common problem of weak and unstable signals of characteristic elements in the application of laser-induced breakdown spectroscopy (LIBS) technology for trace element detection. In this study, the influence of the optical fiber collimation signal enhancement method on the LIBS signal was explored.
View Article and Find Full Text PDFFacial Plast Surg Aesthet Med
January 2025
Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, California, USA.
Various large language models (LLMs) can provide human-level medical discussions, but they have not been compared regarding rhinoplasty knowledge. To compare the leading LLMs in answering complex rhinoplasty consultation questions as evaluated by plastic surgeons. Ten open-ended rhinoplasty consultation questions were presented to ChatGPT-4o, Google Gemini, Claude, and Meta-AI LLMs.
View Article and Find Full Text PDFLasers Med Sci
January 2025
Department of Dermatology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
Vitiligo is a chronic depigmenting condition that causes amelanotic macules and patches on the skin. Despite various treatment options, treating vitiligo is a challenge. This study aimed to evaluate the combination of laser CO fractional and narrow-band ultraviolet B (NB-UVB) versus NB-UVB monotherapy in vitiligo patients.
View Article and Find Full Text PDFGraefes Arch Clin Exp Ophthalmol
January 2025
15-20 National Ophthalmologic Center, Paris, France.
Purpose: Intravitreal injections of anti-VEGF agents are considered as safe, with a very low rate of intraocular inflammations (IOI). Faricimab is a novel intravitreal bispecific antibody targeting both VEGF-A and angiopoietin-Tie2 independently. Despite a safe profile in randomized clinical trials, several real-life studies have reported cases of IOI.
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