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Objectives: Contaminated apparatus and surgical tools pose serious health risks. For such purpose, disinfection chambers are employed. However, these systems rely on mercury-based UV lamps which comes with various drawbacks. These limitations have driven interest in Ultraviolet-C Light Emitting Diode (UV-C LED) technology as a safer and more efficient alternative. However, existing studies have not thoroughly explored the impact of varying intensities of pulse width modulation (PWM) on disinfection efficacy.
Methods: To addess this, the present study designed and tested a LED-based disinfection chamber by employing 4-W 275 nm Surface Mount Device (SMD) LEDs against frequently isolated bacteria. By following prior approach, irradiation time was alternated at 30-s intervals and antibacterial efficacy was assessed through various parameters. Additionally, scanning electron microscopy (SEM) was performed to examine the morphological changes.
Results: Results indicated that the reduction was significantly influenced (p<0.05) with varying PWM levels (60-100 %), achieving 2.05-log and 1.54-log inactivation against and respectively, upon exposure to 51.24 mJ/cm under maximum exposure settings. Moreover, complete cellular damage leading to bleb protrusion and cell-leakage confirmed the disruption of bacterial DNA.
Conclusions: In conclusion, UV-LEDs show great potential for disinfection, with efficiency influenced by PWM and dosage.
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http://dx.doi.org/10.1515/bmt-2025-0070 | DOI Listing |
Rev Sci Instrum
September 2025
International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China.
Radio frequency (RF) control is a key technique in cold atom experiments. We present a compact and efficient RF circuit based on a capacitive transformer network, where a low-frequency coil operating up to 30 MHz serves as both an intrinsic inductor and a power-sharing element. The design enables high current delivery and flexible impedance matching across a wide frequency range.
View Article and Find Full Text PDFAust Endod J
September 2025
State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, Department of Implantology, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.
This study aimed to investigate the biomechanical impact of root canal anatomical variations and restoration techniques on endodontically treated mandibular second molars using finite element analysis. Five root morphologies were modelled: separated-rooted (S), fused-rooted with V-shaped (F-V), U-shaped (F-U) or Ω-shaped (F-Ω) radicular grooves and single-canal fused-rooted (F-O). Micro-CT scans were performed before and after endodontic instrumentation to generate the finite element models: intact teeth, post-and-core crowns with 2- to 3-mm ferrules and endocrowns with 3- to 4-mm pulp chamber extensions.
View Article and Find Full Text PDFPhotoacoustics
October 2025
Hubei Key Laboratory of Intelligent Wireless Communications, Hubei Engineering Research Center of Intelligent IOT technology, College of Electronics and Information Engineering, South-Central Minzu University, Wuhan 430074, China.
A novel gourd-type photoacoustic cell (GTPAC) has been developed, featuring a highly reflective, polished gold film-coated inner wall that minimizes optical loss and maximizes light utilization efficiency. GTPAC integrates two coupled spherical chambers with a radius ratio 2:3, which is close to the golden ratio. Its unique Gaussian curvature distribution enables multi-directional, disordered light beam reflection without complex optical alignment.
View Article and Find Full Text PDFJDS Commun
September 2025
Brazilian Agricultural Research Corporation, Juiz de Fora, Minas Gerais, Brazil, 36038-330.
This technical note describes a small ruminant respiration chamber system designed to accurately quantify the production of carbon dioxide (CO) and methane (CH). The system consists of 3 open-circuit respiration chambers, flow meters, gas analyzers, and an accessible environmental control system. To validate its performance, gas recovery tests were conducted by injecting CO and CH at 4 constant flow rates: 0.
View Article and Find Full Text PDFAm J Ophthalmol
September 2025
Dean McGee Eye Institute, University of Oklahoma, Oklahoma City, Oklahoma, USA. Electronic address:
Purpose: To compare refractive prediction accuracy using simulated keratometry (SimK) measurements obtained from a Scheimpflug tomographer (Pentacam AXL, Oculus) versus keratometry (K) measurements obtained from an optical biometer utilizing telecentric keratometry (IOLMaster 700 (IOLM700), Carl Zeiss Meditec AG) applied to modern IOL power calculation formulas.
Design: Retrospective accuracy and validity analysis METHODS: Setting: Private practice center STUDY POPULATION: Five hundred eighty-nine eyes with preoperative SimK and K measurements undergoing phacoemulsification and implantation of monofocal IOL (Clareon SY60WF IOL, Alcon Laboratories, Inc.).