We first demonstrated a continuously and widely giant-pulse duration tunable laser based on a short monolithic Nd:YAG/Cr:YAG ceramic by cavity-length control in 100 Hz operation. The tuning range of pulse duration τ was from 0.5 to 9 ns as keeping peak powers of over 0.5 MW up to 6 MW. The characteristics of the ceramic laser was discussed in detail such as cavity-length dependent beam pattern and divergence, pulse shape, pulse energy due to the transverse and longitudinal modes, and an elliptical polarization status. Laser induced breakdown in laboratory air was investigated as a function of τ in sub-nanosecond region using the developed laser. Air-breakdown threshold intensity I was measured using three different focusing conditions. We confirmed that 1) the measured I was almost constant at the longer τ than τ named as limit-pulse-duration of cascade ionization (CI), 2) I had ~τ scaling for τ < τ, 3) the increase of I is not connected to a specific intensity level, and 4) τ was not constant and depended on focusing conditions. These phenomena were discussed with considering temporal-spatial intensity of laser.
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Spectrochim Acta A Mol Biomol Spectrosc
December 2024
Saha's Spectroscopy Laboratory, Department of Physics, University of Allahabad, Prayagraj, India.
The present study demonstrates the applicability of non-destructive and rapid spectroscopic techniques, specifically laser-induced fluorescence, ultraviolet-visible, and confocal micro-Raman spectroscopy, as non-invasive, eco-friendly, and robust multi-compound analytical methods for assessing biochemical changes in maize seedling leaves resulting from the treatment of aluminium oxide nanoparticles. The recorded fluorescence spectrum of the leaves shows that the treatment of different concentration of aluminium oxide nanoparticles decreases the chlorophyll content as observed by the increase in fluorescence emission intensity ratio (FIR = I/I). The analysis of ultraviolet-visible absorption measurements reveals that the amount of chlorophyll a, chlorophyll b, total chlorophyll and carotenoid decrease for treated plants with respect to untreated seedlings.
View Article and Find Full Text PDFExp Eye Res
December 2024
Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, Shanghai, 200031, China; Key laboratory of Myopia and Related Eye Diseases, NHC, Chinese Academy of Medical Sciences, 83 Fenyang Road, Shanghai, 200031, China; Shanghai Key Laboratory of Visual Impairment and Restoration, 83 Fenyang Road, Shanghai, 200031, China. Electronic address:
Choroid neovascularization (CNV) is a distinct type of age-related macular degeneration (AMD) with a poor prognosis and responsible for the majority of vision loss in the elderly population. The laser-induced CNV model is a well-established animal model frequently used to study CNV. In this study, we performed an integrated analysis of metabolomic and transcriptomic data from CNV samples, utilizing multiple approaches including single-sample gene set enrichment analysis (ssGSEA), correlation analysis, and weighted gene co-expression network analysis (WGCNA), alongside various bioinformatics platforms, to identify key metabolic and immune signatures and to investigate their interplay during angiogenesis.
View Article and Find Full Text PDFInt J Pharm
December 2024
School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu 212013, PR China. Electronic address:
Alzheimer's disease (AD) is a neurodegenerative disease that is significantly characterized by cognitive and memory impairments, which worsen significantly with age. In the late stages of AD, metal ion disorders and an imbalance of reactive oxygen species (ROS) levels occur in the brain microenvironment, which causes abnormal aggregation of β-amyloid (Aβ), leading to a significant worsening of the AD symptoms. Therefore, we designed a composite nanomaterial of macrophage membranes-encapsulated Prussian blue nanoparticles (PB NPs/MM).
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
December 2024
Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
Introduction: Squamous cell carcinoma (SCC) is the most common malignancy of the head and neck region. Combination therapy potentially enhances the effectiveness beyond that of each treatment alone. This study aimed to assess whether photodynamic therapy (PDT), using methylene blue as a photosensitizer in conjunction with doxorubicin, produces synergistic effects on the apoptosis of the oral squamous cell carcinoma (OSCC) cell line.
View Article and Find Full Text PDFReprod Health
December 2024
UNDP‑UNFPA‑UNICEF‑WHO‑World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), Department of Sexual and Reproductive Health and Research, World Health Organization, 20 Avenue Appia, 1211, Geneva, Switzerland.
Background: The use of medical abortion using either a combination of mifepristone and misoprostol, or misoprostol alone has contributed to increased safety and decreased mortality and morbidity. The availability of quality medical abortion medicines is an essential component in the provision of quality abortion care. Understanding the factors that influence the availability of medical abortion medicines is important to help in-country policymakers, program planners, and providers improve availability and use of medical abortion.
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