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Rotation Periods of Nine ROSAT Selected Solar-Type Stars

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 551-557页

作者： Li-feng Xing Shuang-yi zhao wei Su Yan Shen xiao-Bin zhang Jian-Yan wei Department of Technology and Physics Zhengzhou Unversity of Light Industry Zhengzhou 450002 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Department of Physics Xingtai University Xingtai 054001

We monitored 16 X-ray selected young solar-type stars for light variation and found appreciable periodic light variability with amplitudes of a few hundredths of a magni- tude in nine of the objects. Using the method of Phase Dispersion Minimization （PDM） and Fourier analysis （software PERIOD04）, the rotation periods of these stars were determined from the photometric data. The rotation periods of all nine stars are shorter than about 3 days. It is suggested that, as with the Pleiades cluster, small amplitude light variations are quite common among young solar-type stars with rotation periods around 3 days or less. This gives further evidence for the spin up of solar-type stars predicted by models of angular momentum evolution of pre-main sequence stars.

关键词： stars: late-type - stars: pre-main sequence - stars: rotation

Genome-wide analysis of OCT4 binding sites in glioblastoma cancer cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第10期12卷 812-819页

作者： Xue-feng FAN wei-yi zhang Na zhao wei YU dong DING Xu HONG Li-sha LI hua-rong zhang Shu ZHENG Biao-yang LIN Key Laboratory of Cancer Prevention and Intervention of Ministry of Education Key Laboratory of Molecular Biology in Medical Sciences of Zhefiang Province Cancer Institute the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Systems Biology Div＆ion Zhejiang-California International Nanosystems Institute （ZCNI） Zhejiang University Hangzhou 310029 China

OCT4, a member of the POU family of gene products, is an octamer motif-binding transcription factor. As it is known to play a crucial role in cancer processes including proliferation, invasion, and chemoradioresistance, it is important to identify the direct targets of OCT4 in living cancer cells. Here, chromatin immunoprecipitation-sequencing （ChlP-seq） was used to identify OCT4 binding sites in glioblastoma cancer cells. The results showed that 5438 OCT4 binding sites were localized in the glioblastoma cancer genome and that these sites contained a consensus sequence TTTkswTw （k=T or G, s=C or G, w=A or T）, which occurred 3931 times in 2312 OCT4 binding regions. Furthermore, binding motifs of some other transcription factors were identified in OCT4 binding regions. Our results provide a valuable dataset for understanding gene regulation mechanisms underlying the function of OCT4 in glioblastoma cancer.

关键词： OCT4 Chromatin immunoprecipitation-sequencing (ChlP-seq) DNA binding region Glioblastoma

Vasculature-on-a-chip with stretchable sensor for recapitulating hemodynamics and electrochemical monitoring of endothelium

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Science China Chemistry 2023年第11期66卷 3314-3322页

作者： Wen-Ting Fan yi zhao feng Hong Yan-Ling Liu wei-hua huang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

Vascular endothelium can perceive fluid shear stress(FSS)and cyclic circumferential stretch(CCS)caused by the pulsatile blood flow,and translate the hemodynamics into biochemical signals to regulate vascular ***,existing methods provide little information about the real-time biochemical responses of endothelium when exposed to dynamic FSS and ***,a vasculature-on-a-chip integrated with stretchable sensing is engineered for recapitulating the hemodynamic milieus and in-situ monitoring biochemical responses of endothelial *** integrated device is developed by sandwiching a robust stretchable electrode between an upper fluidic channel and a lower pneumatic *** fluidic and pneumatic channels enable the simultaneous recapitulation of both FSS and CCS,and the integrated sensor exhibits excellent cell-adhesive capacity and electrochemical sensing stability even after long-term hemodynamic *** allow real-time monitoring of hemodynamic form-and duration-dependent endothelium responses,and further efficacy investigation about a recommended drug for COVID-19,demonstrating the great potential in vascular disease and drug screening.

关键词： vasculature-on-a-chip stretchable sensor hemodynamic forces electrochemical monitoring endothelium responses

Diagnostics of Femtosecond Laser-Plasmas Using Fundamental and Second Harmonic Emission

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Chinese Physics Letters 2000年第11期17卷 818-820页

作者： zhao Li-Zeng zhang Ping feng Bao-hua wei Zhi-yi zhang Jie Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039

By observing the fundamental and second harmonic emission from a plasma produced by a 150fs,5mJ laser at 800nm,the electron temperature,the expansion speed and the scalelength of the plasma have been *** the polarization of the fundamental and second harmonic emission has been *** could be a useful diagnostic for modulation at the critical surface of the plasma.

关键词： polarization Femto second

On the Performances of Estimating Stellar Atmospheric Parameters from CSST Broad-band Photometry

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Research in Astronomy and Astrophysics 2024年第4期24卷 161-173页

作者： Rui-feng Shi Yang huang Xin-yi Li hua-wei zhang School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China CAS Key Lab of Optical Astronomy Key Laboratory of Space Astronomy and TechnologyNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China College of Physics and Electronic Engineering Qilu Normal UniversityJinan 250200China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky *** surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution *** this study,we explore the capability of measuring stellar atmospheric parameters from Chinese Space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model *** find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the *** to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,*** precision of the effective temperature estimated from broad-band colors are within 50 K.

关键词： methods:data analysis stars:abundances surveys

Gastrointestinal stromal tumor with multisegmental spinal metastases as first presentation:A case report and review of the literature

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World Journal of Clinical Cases 2021年第6期9卷 1490-1498页

作者： Yan Kong xiao-wei Ma Qian-Qian zhang yi zhao He-Lin feng Department of Medical Oncology The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina Department of Orthopedics The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina Department of Gynecology Hebei Medical University Second Affiliated HospitalShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Gastrointestinal stromal tumor(GIST)usually originates in the stomach,followed by the small intestine,rectum,and other parts of the gastrointestinal *** most common sites of metastasis are the liver and peritoneum,whereas spinal metastases from GIST are extremely *** SUMMARY We found a case of GIST with the first presentation of multilevel spinal metastases involving the thoracic and lumbar vertebrae.A 61-year-old Chinese man presented to our clinic because of pain in his lower back and hip for 10 d without ***,computed tomography(CT)and magnetic resonance imaging(MRI)revealed abnormal signals in the vertebral appendages of T12 and L4 accompanied by spinal canal stenosis,which was considered as tumor *** there were no metastases to vital organs,posterior thoracic and lumbar spinal decompression+adnexal mass resection+pedicle internal fixation was adopted to achieve local cure and prevent nerve *** results of histopathological studies were consistent with the metastasis of *** local recurrence or new metastases were found at the 6-mo follow-up at the surgical *** patient has no neurological symptoms at *** is worth mentioning that a rectal mass was found and surgically removed 1 mo after the patient was discharged from hospital,and the pathological diagnosis of the mass was *** By reviewing 26 previously reported cases of spinal metastasis in GIST,it was found that spinal metastasis of GIST has become more common in recent years,so the possibility of early spinal metastasis should be *** and MRI are of great value in the diagnosis of spinal metastatic tumors,and pathological biopsy is the gold standard for the diagnosis of metastatic *** is safe and feasible to treat isolated spinal metastasis in GIST by excising metastatic masses,decompressing the spinal canal,and stabilizing the spine.

关键词： Spinal metastasectomy Gastrointestinal stromal tumor Multisegmental spinal metastases Magnetic resonance imaging Case report

Synthesis,crystal structure and thermal behavior of 4-amino-3,5-dinitropyrazole copper salt

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Chinese Chemical Letters 2014年第6期25卷 902-906页

作者： ying-Lei Wang feng-Qi zhao Yue-Ping Ji Jian-hua yi Ting An wei-xiao Liu Science and Technology on Combustion and Explosion Laboratory Xi'an Modern Chemistry Research Institute

A novel energetic combustion catalyst, 4-amino-3,S-dinitropyrazole copper salt （[Cu（adnp）2（H2O）2]）, was synthesized in a yield of 93.6% for the first time. The single crystal of [Cu（adnp）2（H2O）2] was determined by single crystal X-ray diffraction. It crystallizes in a triclinic system, space group p^-1 with crystal parameters a = 5.541（3） A, b = 7.926（4） A, c = 10.231（5） A,β = 101.372（8）°, V = 398.3（3） A3, Z = 1, μ = 1.467 mm^-1, F（0 0 0） = 243, and Dc = 2.000 g cm^-3. The thermal behavior and non-isothermal decomposition reaction kinetics of [Cu（adnp）2（H2O）2] were studied by means of different heating rate differential scanning calorimetry （DSC）. The kinetic equation of major exothermic decomposition reaction for [Cu（adnp）2（H2O）2] was obtained. The entropy of activation （△S≠）, enthalpy of activation （△H≠）, free energy of activation （△G≠）, the self-accelerating decomposition temperature （TSADT） and the critical temperature of thermal explosion （Tb） are 59.42 j mol^-1 K^-1, 169.5 kJ mol^-1, 1141.26 kJ mol ^-1 457.3 K and 468.1 K, respectively.

关键词： Physical chemistry 4-Amino-3,5-dinitropyrazole copper salt Energetic combustion catalyst Crystal structure Thermal behavior

Novel sesquiterpenoids isolated from Chimonanthus praecox and their antibacterial activities

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Chinese Journal of Natural Medicines 2018年第8期16卷 621-627页

作者： LOU hua-Yong zhang Yu MA xiao-Pan JIANG Sai WANG Xiang-Pei yi Ping LIANG Guang-yi WU Hong-Mei feng Jing JIN feng-Yun PAN wei-dong Guiyang College of Traditional Chinese Medicine Guiyang 550002 China State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Guiyang 550014 China The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences Guiyang 550014 China

In the present study,four new sesquiterpenoids,chimonols A–D(compounds 1–4),together with four known compounds(5–8) were isolated from the Et OAc extract of Chimonanthus praecox *** structures of these new compounds were elucidated on the basis of spectroscopic techniques(UV,IR,MS,and 1 D and 2 D NMR),and their absolute configurations were established by comparing experimental and calculated electronic circular dichroism(ECD) *** 1–8 were evaluated for antimicrobial activities and the minimum inhibitory concentrations(MICs) were determined by the broth microdilution method in 96-well culture *** 1,2,and 7 exhibited weak antibacterial effects for ***(ATCC 6538),***(ATCC 11775),and ***(ATCC 10145) with MIC values being 158–249 μg·mL^(-1).Compounds 3–7 showed activities against ***(ATCC 2001) and ***(ATCC 43300) with MIC values being 128–197 μg·mL^(-1).Compounds 1–4 showed activity against ***(ATCC 25923) with MIC values being 162–254 μg·mL^(-1).The present study provided a basis for future evaluation of these compounds as antibacterial agents.

关键词： Sesquiterpenoids Chimonanthus praecox Electronic circular dichroism Antimicrobial activities

A three-dimensional matrix system containing melatonin and neural stem cells repairs damage from traumatic brain injury in rats

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Neural Regeneration Research 2022年第11期17卷 2512-2517页

作者： Xuan-Yu Fang Da-wei zhao Chao zhang Hong-Fei Ge Xu-Yang zhang feng-Chun zhao yi-Bin Jiang hua feng Rong Hu Department of Neurosurgery and Key Laboratory of Neurotrauma Southwest HospitalArmy Medical UniversityChongqingChina

Brain lesions can cause neural stem cells to activate,proliferate,diffe rentiate,and migrate to the injured ***,after traumatic brain injury,brain tissue defects and microenvironment changes greatly affect the survival and growth of neural stem cells;the resulting reduction in the number of neural stem cells impedes effective repair of the injured *** can promote the survival,proliferation,and differentiation of neural stem cells under adverse conditions such as oxidative stress or hypoxia that can occur after traumatic brain ***,we investigated the therapeutic effects of melatonin combined with neural stem cells on traumatic brain injury in ***,in vitro studies confirmed that melatonin promoted the survival of neural stem cells deprived of oxygen and ***,we established a three-dimensional Matrigel-based transplantation system containing melatonin and neural stem cells and then used it to treat traumatic brain injury in *** found that treatment with the Matrigel system containing melatonin and neural stem cells decreased brain lesion volume,increased the number of surviving neuro ns,and improved recove ry of neurological function compared with treatment with Matrigel alone,neural stem cells alone,Matrigel and neural stem cells combined,and Matrigel and melatonin *** findings suggest that the three-dimensional Matrigelbased transplantation system containing melatonin and neural stem cells is a potential treatment for traumatic brain injury.

关键词： cell therapy magnetic resonance imaging Matrigel melatonin neural stem cells neurological function recovery three-dimensional transplantation traumatic brain injury