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Our anisotropic rate equation model outlines the relationship between the relaxation dynamics in a four-level solid-state laser and its anisotropic gain properties. Anisotropic pump rates and stimulated emission cross-sections were included to account for specific atom orientations in the gain material. The model is compared with experimental measurements of two relaxation oscillation frequencies which are related to the anisotropic atom-laser interaction in orthogonally polarized dual-mode lasers. The model predicts that crystal orientation and pump polarization affect the laser operation characteristics, as found experimentally. The gain anisotropy influences the fast laser dynamics, as in single-mode relaxation oscillations.
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http://dx.doi.org/10.1364/oe.17.006053 | DOI Listing |
Brain Commun
August 2025
CNNP Lab (www.cnnp-lab.com), School of Computing, Newcastle University, Newcastle upon Tyne NE4 5BX, United Kingdom.
Non-invasive neuroimaging is important in epilepsy to help identify cerebral abnormalities. Abnormally reduced fractional anisotropy (FA) in deep white matter (WM) from diffusion-weighted imaging (DWI) is widely reported in large multi-cohort studies across all types of epilepsies. However, abnormalities in FA for superficial WM are rarely investigated in epilepsy.
View Article and Find Full Text PDFMicromachines (Basel)
May 2025
Laboratory of Digital IC and Space Application, School of Microelectronics, Xidian University, Xi'an 710071, China.
This study systematically investigates the electrical characteristics of the vertical NPN bipolar junction transistor (VNPN BJT) in the strong magnetic field environment, focusing on analyzing the effects of magnetic field direction and intensity on key parameters such as terminal current and current gain (). The simulation results show that the magnetic field induces changes in the carrier distribution, thereby affecting the current transport path. Through the in-depth analysis of electron motion trajectories, potential distribution, and Hall voltage, this paper reveals the physical mechanisms behind the device's characteristic changes under the magnetic field and discovers that the inherent asymmetry of the BJT structure induces significant magnetic anisotropy effects.
View Article and Find Full Text PDFMembranes (Basel)
May 2025
Rede de Quimica e Tecnologia-Laboratorio Associado de Quimica Verde, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal.
As a surface-located molecule in biological membranes, cholesterol sulphate (CholS) plays a major role in membrane-driven cell-cell processes and events including platelet-cell adhesion, T-cell receptor signalling, sperm-egg interaction, membrane fusion, and skin differentiation. Despite this, little is known about the biophysical implications of CholS at the membrane in cells and organelles. In this study, we investigate the effect of increasing the content of CholS on the biophysical properties in cholesterol-poor and cholesterol-rich biomimetic models.
View Article and Find Full Text PDFPhys Chem Chem Phys
July 2025
Institute of Physics of the NASU, 46 Nauky Ave., 03028 Kyiv, Ukraine.
New symmetrical anilinosquaraine derivatives with four hydroxyl groups in the molecular core, namely, 2,4-bis[4-[4-(3,5-didecoxyphenoxy)butyl-methyl-amino]-2,6-dihydroxy-phenyl]squaraine (1) and 2,4-bis[4-[6-(3,5-didecoxyphenoxy)hexyl-methyl-amino]-2,6-dihydroxy-phenyl]squaraine (2), were synthesized. Both compounds were found to exhibit manifold linear spectroscopic and nonlinear optical properties with high potential for a number of important multidisciplinary applications. Linear photophysical and photochemical properties of 1 and 2 were assessed in liquid solvents of different polarities at room temperature, including steady-state absorption, emission, and excitation anisotropy spectra, along with fluorescence quantum yields and lifetimes.
View Article and Find Full Text PDFPediatr Neurol
August 2025
Department of Radiology, Affiliated Shenzhen Children's Hospital of Shantou University Medical College, Shenzhen, Guangdong, China. Electronic address:
Background: Nusinersen has been promoted as an effective therapy for improving motor function in patients with spinal muscular atrophy (SMA). Quantitative magnetic resonance imaging (qMRI) is a useful tool to reflect muscle microstructural characteristics. We investigate whether qMRI can provide useful biomarkers for monitoring treatment efficacy in SMA and explore other factors that may predict the treatment response.
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