We present efficient and robust Kerr-lens mode locking (KLM) of a diode-pumped Cr:LiSAF laser using a gain-matched output coupler (GMOC). An inexpensive, battery-powered 660 nm single-spatial-mode diode was used as the pump source. GMOC enhances the effective self-amplitude modulation depth by reducing the gain-filtering effect in broadband KLM operation to provide significant improvement in efficiency and robustness. Pulsing can be initiated without careful cavity alignment and is sustained for hours. 13 fs pulses with an average power of 25 mW have been generated using only 120 mW of pump power. The corresponding pulse energy and peak power is 200 pJ and 15 kW for the 126 MHz repetition rate cavity. Optical-to-optical conversion efficiency of the system is 21%, which represents an order of magnitude improvement in reported efficiencies for such diode-pumped ultrashort-pulse KLM Cr:LiSAF lasers. The obtainable pulse width is currently limited by the dispersion bandwidth of the available optics and can be potentially reduced to below 7 fs.
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http://dx.doi.org/10.1364/OL.39.000327 | DOI Listing |
BMC Med Imaging
January 2025
Department of Magnetic Resonance Imaging, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, 450052, China.
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Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, 119074, Singapore.
The emerging combination of chemotherapy and radionuclide therapy has been actively investigated to overcome the limitations of monotherapy and augment therapeutic efficacy. However, it remains a challenge to design a single delivery vehicle that can incorporate chemotherapeutics and radionuclides into a compact structure. Here, a chelator DOTA- or NOTA-modified Evans blue conjugated camptothecin molecule (EB-CPT) nanoprodrug was synthesized, which could self-assemble into nanoparticles due to its inherent amphiphilicity.
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Pathology Department, Beijing Youan Hospital, Capital Medical University, Beijing, 100000, China.
In the context of chronic liver diseases, where variability in progression necessitates early and precise diagnosis, this study addresses the limitations of traditional histological analysis and the shortcomings of existing deep learning approaches. A novel patch-level classification model employing multi-scale feature extraction and fusion was developed to enhance the grading accuracy and interpretability of liver biopsies, analyzing 1322 cases across various staining methods. The study also introduces a slide-level aggregation framework, comparing different diagnostic models, to efficiently integrate local histological information.
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Noncommunicable Disease Research Center, Jahrom University of Medical Sciences, Jahrom, Iran.
Despite significant advancements in gene delivery and CRISPR technology, several challenges remain. Chief among these are overcoming serum inhibition and achieving high transfection efficiency with minimal cytotoxicity. To address these issues, there is a need for novel vectors that exhibit lower toxicity, maintain stability in serum-rich environments, and effectively deliver plasmids of various sizes across diverse cell types.
View Article and Find Full Text PDFNPJ Vaccines
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Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA.
Dysentery caused by Shigella species remains a major health threat to children in low- and middle-income countries. There is no vaccine available. The most advanced candidates, i.
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