Publications by authors named "Chenxia Yun"

Ethnopharmacological Relevance: Adinandra nitida Merr. ex Li leaves serve as a herbal tea and hold a significant role in traditional Chinese medicine, being applied to assist in tumor treatment. Flavonoids present the primary bioactive constituents in Adinandra nitida Merr.

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We present a detailed exposition of the design for time- and angle-resolved photoemission spectroscopy using a UV probe laser source that combines the nonlinear effects of β-BaB2O4 and KBe2BO3F2 optical crystals. The photon energy of the probe laser can be switched between 6.0 and 7.

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Time-resolved and angle-resolved photoemission spectroscopy (trARPES) is a powerful method to detect the non-equilibrium electronic structure in solid systems. In this study, we report a trARPES apparatus with tunable photon energy selectively among 12, 16.8, and 21.

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Article Synopsis
  • High-order harmonic generation (HHG) creates a wide spectrum of light from the vacuum ultraviolet to extreme ultraviolet range, making it ideal for detailed material analysis.
  • The study presents a high-photon flux HHG source using a two-color laser field, achieving a photon output of 2 × 10^12 phs/s at 21.6 eV.
  • A classical diffraction mounted grating monochromator was developed to cover photon energies from 12 to 40.8 eV, enhancing time resolution by minimizing pulse front tilt and addressing energy resolution broadening due to space charge effects.
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Article Synopsis
  • Animal influenza viruses can threaten human health, and animal models like tree shrews are essential for studying these viruses' cross-species infections and impacts.
  • Tree shrews have shown susceptibility to various human influenza virus subtypes and are becoming important models for researching the pathogenicity of swine and avian influenza viruses, especially subtypes H3N2 and H6N6.
  • In experiments, both SW2783 and ZZ346 strains infected tree shrews effectively, particularly in the upper respiratory tract, but caused mild clinical symptoms and relatively light tissue damage while eliciting immune responses.
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  • The study aimed to investigate the protective effects of mangiferin (MGN) against neurological damage caused by chronic lead (Pb) exposure through the activation of Nrf2-related processes.
  • The research involved 96 Wistar rats divided into different groups, with some receiving DMSA (a standard treatment for lead poisoning) and others receiving varying doses of MGN over four weeks, followed by evaluation using various biochemical and histological methods.
  • Results showed that MGN administration successfully mitigated brain damage and oxidative stress caused by Pb, primarily by activating Nrf2-dependent enzymes and genes, indicating its potential as a neuroprotective agent.
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Mangiferin is the major bioactive ingredient in the leaves of Mangifera indica L., Aqueous extract of such leaves have been traditionally used as an indigenous remedy for respiratory diseases including cough and asthma in Traditional Chinese Medicine. Mangiferin was shown to exert its anti-asthmatic effect by modulating Th1/Th2 cytokines imbalance via STAT6 signaling pathway.

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Objective To detect the level of Toll-like receptor 2 (TLR2) in CD8(+)T cells of chronic HBV infected patients without antiviral treatment. Methods Forty chronic HBV infected donors without antivirus treatment and 19 healthy donors were enrolled in our study. All donors were divided into three groups: a high viral load (HBV DNA>1×10(4) copies/mL) group, a low viral load (HBV DNA>1×10(4) copies/mL) group, and a healthy control group.

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The tree shrew (Tupaia belangeri) diverges from the primate order (Primates) and is classified as a separate taxonomic group of mammals - Scandentia. It has been suggested that the tree shrew can be used as an animal model for studying human diseases; however, the genomic sequence of the tree shrew is largely unidentified. In the present study, we reported the full-length cDNA sequence of the housekeeping gene, β-actin, in the tree shrew.

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Mangiferin is a major bioactive ingredient in Mangifera indica Linn. (Anacardiaceae) leaves. Aqueous extract of such leaves have been used as an indigenous remedy for respiratory diseases like asthma and coughing in traditional Chinese medicine.

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The tree shrews (Tupaia belangeri) diverged from the primate order (Primates) and are classified as Scandentia, a separate taxonomic group of mammals. The tree shrew has been suggested to use an animal model to study human disease but the genomic sequences of tree shrew is largely unidentified. Here we identified the full-length cDNA sequence of a housekeeping gene, Glyceraldehyde 3-phosphate Dehydrogenase (GAPDH), in tree shrew.

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High order harmonics generation from argon gas was comprehensively investigated by using multi-cycle and few-cycle laser pulses. Non-odd order harmonics were observed for sub-5-fs pulses, compare to the normal odd-order harmonics in the multi-cycle case. Theoretic analysis shows that the new spectral structure origins from the asymmetry of laser field in few-cycle pulses.

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The active ingredient of Huyinling, a combination of Chinese traditional medicine, was extracted by five different ethanol concentrations (40%-80%). There were seven groups named as five Huyinling ethanol extract groups (40%, 50%, 60%, 70%, and 80%), metronidazole group and blank control. Each Huyinling ethanol extract group was further divided into five subgroups with final concentration of 6.

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The time delay between the pump and probe pulses in attosecond time-resolved experiments, such as attosecond streaking, is commonly introduced by splitting and recombining the two pulses in an interferometer. This technique suffers from instability in the optical path lengths of the two arms due to mechanical vibration of the optical elements and fluctuating environmental conditions. We present a technique with which the instability of the unconventional interferometer is suppressed while at the same time the time delay is controlled to within 20 as RMS using a feedback loop.

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Double optical gating of high-harmonic generation was used to obtain supercontinuous spectra in the extreme UV (XUV) region including the water window. The spectra supported a 16 as pulse duration that is below one atomic unit of time (24 as). The dependence of the gated spectra on the carrier-envelope phase of the laser provided evidence that isolated attosecond pulses were generated.

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Carrier-envelope (CE) phase stabilization of a two-stage chirped pulse amplifier laser system with regenerative amplification as the preamplifier is demonstrated. The CE phase stability of this laser system is found to have a 90 mrad rms error averaged over 50 laser shots for a locking period of 4.5 h.

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We report a double feedback loop for the improvement of the carrier-envelope phase stabilization of a chirped mirror based femtosecond laser oscillator. By combining the control of the Ti:sapphire crystal temperature and the modulation of the pump power, the carrier envelope offset frequency, fCEO, was locked for close to 20 h, which is much longer than the typical phase stabilization time with only pump power modulation.

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