Exogenous ochronosis is a cutaneous condition characterized by blue-black pigmentation resulting as a complication of long-term application of skin-lightening creams containing hydroquinone and other substances such as quinine, phenol and mercury derivatives. We report a case of a 55-year-old woman who developed exogenous ochronosis as a result of prolonged use of topical hydroquinone for 5 years, characterized by greyish hyperpigmented patches on the nose and cheeks. The diagnosis was confirmed histologically. Treatment with picosecond laser resulted in marked clinical improvement together with improvement in overall texture and quality of the skin.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/jocd.12834 | DOI Listing |
Small
January 2025
Faculty of Physics and Astronomy, Adam Mickiewicz University, Poznan, 61-614, Poland.
The behavior of triple-cation mixed halide perovskite solar cells (PSCs) under ultrashort laser pulse irradiation at varying fluences is investigated, with a focus on local heating effects observed in femtosecond transient absorption (TA) studies. The carrier cooling time constant is found to increase from 230 fs at 2 µJ cm⁻ to 1.3 ps at 2 mJ cm⁻ while the charge population decay accelerates from tens of nanoseconds to the picosecond range within the same fluence range.
View Article and Find Full Text PDFMater Horiz
January 2025
Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Straße 24/25, 14476, Germany.
Two-dimensional transition metal dichalcogenides (2D TMDCs) can be combined with organic semiconductors to form hybrid van der Waals heterostructures. Specially, non-fullerene acceptors (NFAs) stand out due to their excellent absorption and exciton diffusion properties. Here, we couple monolayer tungsten diselenide (ML-WSe) with two well performing NFAs, ITIC, and IT-4F (fluorinated ITIC) to achieve hybrid architectures.
View Article and Find Full Text PDFAll-inorganic perovskite materials have been widely used in various devices, including lasers, light-emitting diodes (LEDs), and solar cells, due to their exceptional optoelectronic properties. Devices utilizing high-quality single crystals are anticipated to achieve significantly enhanced performance. In this work, we present a high-performance vertical cavity surface emitting laser (VCSEL) based on a single-crystal CsPbBr microplatelet, fabricated through a simple solution process and sandwiched between two distributed Bragg reflector (DBRs).
View Article and Find Full Text PDFWe demonstrate a (FMCW) light detection and ranging (LIDAR) system utilizing a (SNSPD) to measure vibrational spectra using reflected signals at the single-photon level. By determining the time-variant Doppler shift of the reflected probe signal, this system successfully reconstructs various audio signals, including pure sinusoidal, multi-tonal, and musical signals, up to 200 Hz, limited by the laser frequency modulation rate and the Nyquist sampling theorem. Additionally, we employ scanning galvo mirrors to perform 3D measurements and map audio signals from different regions in the scanned field of view.
View Article and Find Full Text PDFAtoms in Rydberg states are an important building block for emerging quantum technologies. While excitation to Rydberg orbitals is typically achieved in more than tens of nanoseconds, the physical limit is in fact much faster, at the ten picoseconds level. Here, we tackle such ultrafast Rydberg excitation of a rubidium atom by designing a dedicated pulsed laser system generating 480 nm pulses of 10 ps duration.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!