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We describe a technique to enhance both the weak-signal relative sensitivity and the dynamic range of a laser scanning optical microscope. The technique is based on maintaining a fixed detection power by fast feedback control of the illumination power, thereby transferring high measurement resolution to weak signals while virtually eliminating the possibility of image saturation. We analyze and demonstrate the benefits of adaptive illumination in two-photon fluorescence microscopy. 相似文献
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Trends in ultrashort and ultrahigh power laser pulses based on optical parametric chirped pulse amplification 下载免费PDF全文
Since the proof-of-principle demonstration of optical parametric amplification to efficiently amplify chirped laser pulses in 1992,optical parametric chirped pulse amplification(OPCPA)became the most promising method for the amplification of broadband optical pulses.In the meantime,we are witnessing an exciting progress in the development of powerful and ultrashort pulse laser systems that employ chirped pulse parametric amplifiers.The output power and pulse duration of these systems have ranged from a few gigawatts to hundreds of terawatts with a potential of tens of petawatts power level.Meanwhile,the output pulse duration based on optical parametric amplification has entered the range of fewoptical-cycle field.In this paper,we overview the basic principles,trends in development,and current state of the ultrashort and laser systems based on OPCPA,respectively. 相似文献
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4‐Benzamido‐TEMPO catalyzed oxidation system for conversion of a wide range of alcohols to the aldehydes or ketones with NaBrO3 under room temperature conditions has been developed. The credible, operationally convenient and economical, and condition mild oxidation protocol is particularly of interest in laboratory and in fine chemicals manufacture. 相似文献
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Dr. Nan Chen Dr. Yuan Liu Yuanpei Li Prof. Dr. Chu Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16203-16209
Protein 4′-phosphopantetheinylation is an essential post-translational modification (PTM) in prokaryotes and eukaryotes. So far, only five protein substrates of this specific PTM have been discovered in mammalian cells. These proteins are known to perform important functions, including fatty acid biosynthesis and folate metabolism, as well as β-alanine activation. To explore existing and new substrates of 4′-phosphopantetheinylation in mammalian proteomes, we designed and synthesized a series of new pantetheine analogue probes, enabling effective metabolic labelling of 4′-phosphopantetheinylated proteins in HepG2 cells. In combination with a quantitative chemical proteomic platform, we enriched and identified all the currently known 4′-phosphopantetheinylated proteins with high confidence, and unambiguously determined their exact sites of modification. More encouragingly, we discovered, using targeted chemical proteomics, a potential 4′-phosphopantetheinylation site in the protein of mitochondrial dehydrogenase/reductase SDR family member 2 (DHRS2). 相似文献
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Nonlinear Dynamics - This article investigates the issue of hybrid-triggered control for fuzzy Markov jump system under input saturation. First, a hybrid-triggered control scheme is presented,... 相似文献
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This work reported the discovery of N-triflimide (NTf)-based zwitter-ionic liquids (ZILs) that exhibit UCST-type phase transitions in water, and their further structural optimization in fine-tuning polarity to ultimately afford newfangled thermosensitive materials carrying attractive and biocompatible Tc values that clearly demonstrated the true value of the tunability of ZIL structure. This research established that with non-aromatic, acyclic ZILs as small-molecule thermoresponsive materials, their mixing and de-mixing with water triggered by temperatures are entirely reversible. 相似文献