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Antioxidant xanthones and anthraquinones isolated from a marine-derived fungus Aspergillus versicolor

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Chinese Journal of Natural Medicines 2018年第3期16卷 219-224页

作者： WU Ze-Hong LIU Dong xu Ying CHEN jian-liang LIN Wen-Han The Eighth Affiliated Hospital Sun Yat-sen University State Key Laboratory of Natural and Biomimetic Drugs Peking University Shenzhen Key Laboratory of Marine Bioresource & Eco-environmental Science Shenzhen Engineering Laboratory for Marine Algal Biotechnology College of Life Science Shenzhen University

Chemical examination of an EtOAc extract of cultured Aspergillus versicolor fungus from deep-sea sediments resulted in the isolation of four xanthones, eight anthraquinones and five alkaloids, including a new xanthone, oxisterigmatocystin D （1） and a new alkaloid, aspergillusine A （13）. High resolution electron impact mass spectrometry （HR-EI-MS）, FT-IR spectroscopy, and NMR techniques were used to elucidate the structures of these compounds, and the absolute configuration of compound 1 was established by its NMR features and coupling constant. Furthermore, the biosynthesis pathway of these xanthones and anthraquinones were deduced, and their antioxidant activity and cytotoxicity in human cancer cell lines （HTC-8, Bel-7420, BGC-823, A549, and A2780） were evaluated. The trolox equivalent antioxidant capacity （TEAC） assay indicated most of the xanthones and anthraquinones possessing moderate antioxidant activities. The Nrf2-dependent luciferase reporter gene assay revealed that compounds 6, 7, 9, and 12 potentially activated the expression of Nrf2-regulated gene. In addition, compounds 5 and 11 showed weak cytotoxicity on A549 with the ICs0 values of 25.97 and 25.60 gmol·L^-1, respectively.

关键词： Aspergillus versicolor Xanthones Anthraquinones Antioxidant activity Cytotoxicity

Construction of a new regular LDPC code for optical transmission systems

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Optoelectronics Letters 2013年第3期9卷 204-207页

作者： YUAN jian-guo TONG Qing-zhen xu liang HUANG Sheng Key Lab. of Optical Fiber Communications Technology Chongqing University of Posts and TelecommunicationsChongqing 400065 China

A novel construction method of the check matrix for the regular low density parity check （LDPC） code is proposed. The novel regular systematically constructed Gallager （SCG）-LDPC（3969,3720） code with the code rate of 93.7% and the redundancy of 6.69% is constructed. The simulation results show that the net coding gain （NCG） and the distance from the Shannon limit of the novel SCG-LDPC（3969,3720） code can respectively be improved by about 1.93 dB and 0.98 dB at the bit error rate （BER） of 10s, compared with those of the classic RS（255,239） code in ITU-T G.975 recommendation and the LDPC（32640,30592） code in ITU-T G.975.1 recommendation with the same code rate of 93.7% and the same redundancy of 6.69%. Therefore, the proposed novel regular SCG-LDPC（3969,3720） code has excellent performance, and is more suitable for high-speed long-haul optical transmission systems.

关键词：规则LDPC码光传输系统低密度奇偶校验 ITU-T 代码率校验矩阵正规系统仿真结果

Values of a novel pyroptosis-related genetic signature in predicting outcome and immune status of pancreatic ductal adenocarcinoma

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Gastroenterology Report 2022年第1期10卷 476-489页

作者： Xiang xu Jia-Hua liang jian-Hui Li Qiong-Cong xu Xiao-Yu Yin Department of Pancreato-Biliary Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdongP.R.China

Background Pyroptosis is an emerging form of programmed cell death associated with progression in ***,there are few studies reporting on the association between pancreatic ductal adenocarcinoma(PDAC)and ***,we aimed to construct a pyroptosis-related genetic signature to predict the clinical outcome and immune status in PDAC *** RNA-seq data of 176 PDAC patients from The Cancer Genome Atlas(TCGA)and 167 PDAC patients from the Genotype-Tissue Expression Project were analysed for pyroptosis-related differentially expressed genes(DEGs)between PDAC and normal *** risk signature of DEGs was analysed using the least absolute shrinkage and selection operator(LASSO)Cox regression analysis and its accuracy was validated in the Gene Expression Omnibus(GEO)cohort(n=190).Functional enrichment analyses were performed to explore the mechanisms of the *** immune characteristics were evaluated using single-sample gene set enrichment analysis and ESTIMATE algorithms for each *** A nine-gene risk signature was generated from LASSO Cox regression analysis and classified PDAC patients into either a high-or low-risk group according to the median risk *** high-risk group had significantly shorter overall survival than the low-risk group and it was verified in the external GEO database.A nomogrambased on the risk signature was constructed and showed an ideal prediction *** enrichment analyses revealed that pyroptosis might regulate the tumor immune microenvironment in *** infiltration evaluation suggested that immune status was more activated in the low-risk group than in the high-risk *** The risk signature encompassing nine pyroptosis-related genes may be a prognostic marker for *** might affect the prognosis of PDAC patients via regulating the tumor immune microenvironment.

关键词： pancreatic ductal adenocarcinoma pyroptosis prognosis immune

Few-layer WSe2 lateral homo-and hetero-junctions with superior optoelectronic performance by laser manufacturing

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Science China(Technological Sciences) 2020年第8期63卷 1531-1537页

作者： LI Yang YANG jian ZHAN ZhaoYao WU Jumiati LI Hai ZHEN liang HE QiYuan xu ChengYan School of Materials Science and Engineering MOE Key Laboratory of Micro-Systems and Micro-Structures ManufacturingHarbin Institute of TechnologyHarbin 150001China Center for Programmable Materials School of Materials Science and EngineeringNanyang Technological UniversitySingapore 639798Singapore School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Tech University(NanjingTech)Nanjing 211816China Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China

Lateral hetero-junctions are considered as potential candidate for building blocks in modern electronics and optoelectronics,however,the construction of which remains a *** this work,by using a laser-assisted manufacture technique,WSe2/WO3-x hetero-junction and monolayer/trilayer WSe2 homo-junction with Schottky diode like behavior are fabricated,both of which present competitive performance for photodetection and power generation in a wide range of wavelengths from ultraviolet to infrared,with maximum photoresponsivity of 10 A/W,external quantum efficiency of 14%,and power conversion efficiency of 1.3%.Combined with Kelvin probe microscopy and electrical transport measurements,it is demonstrated that the barrier-induced built-in electric field at WSe2/WO3-x interface,and the energy band discontinuities at the monolayer/trilayer WSe2 interface facilitate the separation of photo-generated electron-hole *** work provides a solid step towards the controllable construction of lateral junctions by laser-assisted manufacture for exploiting van der Waals materials-based novel electronic and optoelectronic applications.

关键词： laser manufacture lateral heterostructure optoelectronic performance WSe2

Importance of incorporating systemic cerebroarterial hemodynamics into computational modeling of blood flow in intracranial aneurysm

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Journal of Hydrodynamics 2020年第3期32卷 510-522页

作者： Zhi-qiang Zhang Li-jian xu Rong Liu Xiao-sheng Liu Bing-Zhao Fu-you liang School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai 200240China Institute of Textiles and Clothing The Hong Kong Polytechnic UniversityHong KongChina Department of Radiology Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Neurosurgery Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Institute for Personalized Medicine Sechenov UniversityMoscow 119991Russia

The importance of properly treating boundary conditions (BCs) in numerical simulation of hemodynamics in intracranial aneurysm (IA) has been increasingly recognized. In this study, we constructed three types of computational model for each IA to investigate how the outcome of numerical simulation is affected by the treatment of BCs. The first type of model (i.e., Type-A model) was obtained by applying 3-D hemodynamic modeling to the entire cerebral arterial network, with its solution being taken as the reference for evaluating the performance of the other two types of model (i.e., Type-B and Type-C models) in which 3-D modeling was confined to the aneurysm region. In addition, patient-specific 1-D models of the cerebral arterial network were developed to provide hemodynamic information for setting the inflow/outflow BCs of the 3-D models. Numerical tests on three IAs revealed that prescribing the outflow BCs of a localized 3-D aneurysm model based on 1-D model-simulated outflow division (i.e., Type-B model) instead of imposing the free outflow BC on all outlets (i.e., Type-C model) helped to improve the fidelity of the simulation of intra-aneurysmal hemodynamics, but could not guarantee a complete reproduction of the reference solution obtained by the Type-A model. Moreover, it was found that the outcome of hemodynamic simulation was more sensitive to the treatment of BCs when an aneurysm was located at arterial bifurcation rather than sidewall. These findings highlight the importance of taking into account systemic cerebroarterial hemodynamics in computational modeling of hemodynamics in IAs, especially those located at bifurcations.

关键词： Intracranial aneurysm systemic cerebroarterial hemodynamics boundary conditions computational model

An indoor calibration light source of the transmissometers based on spatial light modulation

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Optoelectronics Letters 2022年第2期18卷 65-71页

作者： liang Jing ZHANG Guoyu ZHANG jian xu Da CHONG Wei SUN Jiliang School of Opto-Electronic Engineering Changchun University of Science and TechnologyChangchun 130022China1 Opto-Electronic Measurement and Control Instrumentation Jilin Province Engineering Research CenterChangchun 130022China Key Laboratory of Opto-Electronic Measurement and Optical Information Transmission Technology Ministry of EducationChangchun 130022China Meteorological Observation Center China Meteorological AdministrationBeijing 100081China

Aiming at the problem that the calibration results of the transmissometers cannot be traced to the meteorological optical range(MOR) defined by the World Meteorological Organization(WMO). We designed an indoor calibration light source of the transmissometers based on spatial light modulation, focusing on the design of a non-intersecting CzernyTurner spectroscopic system which achieved a spectral resolution of less than 1 nm in the range from 380 nm to 780 nm. Then, the calibration light source’s spectrum matching model is established and the digital micromirror device(DMD)’s surface illuminance distribution law is simulated and analyzed. Finally, the MOR error of the calibrated light source is inverted. The results show that the simulation spectrum error of the 2 700 K absolute color temperature is below ±7.4% in the wavelength range from 380 nm to 780 nm, and the MOR error meets the requirements of the International Civil Aviation Organization in 40-2 000 m of MOR.

关键词： source light error

MicroRNA-22 inhibits proliferation and promotes differentiation of satellite cells in porcine skeletal muscle

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Journal of Integrative Agriculture 2020年第1期19卷 225-233页

作者： Hong Quyen Dang xu Gu-li HOU Lian-jie xu jian HONG Guang-liang Chingyuan Hu WANG Chong National Engineering Research Center for Breeding Swine Industry/Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding/College of Animal Science South China Agricultural UniversityGuangzhou 510642P.R.China Bac Giang Agricultural and Forestry University Bac Giang 26000Viet Nam Department of Human Nutrition Food and Animal SciencesCollege of Tropical Agriculture and Human ResourcesUniversity of Hawaii at ManoaHonoluluHI 96822USA

Pig is an important economic animal in China. Improving meat quality and meat productivity is a long time issue in animal genetic breeding. Micro RNAs(mi RNAs) are short non-coding RNAs that participate in various biological processes, such as muscle development and embryogenesis. mi R-22 differentially expresses in embryonic and adult skeletal muscle. However, the underlying mechanism is unclear. In this study, we investigated mi R-22 function in proliferation and differentiation of porcine satellite cells(PSCs) in skeletal muscle. Our data show that mi R-22 expressed in both proliferation and differentiated PSCs and is significantly upregulated(P<0.05) during differentiation. After treated with the mi R-22 inhibitor, PSCs proliferation was significantly increased(P<0.05), as indicated by the up-regulation(P<0.01) of cyclin D1(CCND1), cyclin B1(CCNB1) and down-regulation(P<0.05) of P21. Conversely, over-expression of mi R-22 resulted in opposite results. Differentiation of PSCs was significantly suppressed(P<0.05), evidenced by two major myogenic markers: myogenin(Myo G) and myosin heavy chain(My HC), after transfecting the PSCs with mi R-22 inhibitor. Opposite results were demonstrated in the other way around by transfection with mi R-22 mimics. In conclusion, the data from this study indicated that mi R-22 inhibited the PSCs proliferation but promoted their differentiation.

关键词： miR-22 skeletal muscle porcine satellite cells proliferation differentiation

Direct synthesis of nitriles by Cu/DMEDA/TEMPO-catalyzed aerobic oxidation of primary amines with air

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Chinese Chemical Letters 2017年第6期28卷 1336-1339页

作者： Xian-Tao Ma Hao xu Ying-Lin Xiao Chen-liang Su jian-Ping Liu Qing xu SZU-NUS Collaborative Innovation Center for Optoelectronic Science & Technology Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Optoelectronic EngineeringShenzhen University College of Chemistry and Materials Engineering Department Wenzhou University

By screening the copper catalysts,ligands,and the reaction conditions,a simple CuCl/DMEDA/TEMPO catalyst system readily available from commercial sources is developed for a direct and selective synthesis of the useful nitriles by an aerobic oxidation reaction of primary amines using air as an advantageous oxidant under mild conditions.

关键词： Aerobic oxidation Air Amines Copper catalysis Nitriles

Study on tidal gravity observations obtained at stations Zhongshan and Changcheng, Antarctic

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Acta Seismologica Sinica(English Edition) 2001年第3期14卷 325-332页

作者： xu jian-qiao Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences

Based on the international tidal gravity reference values at station Wuhan, the tidal gravity parameters, including the amplitude factors and phase differences are determined accurately by using the observations with three La-Coste-Romberg (LCR) gravimeters (G-589, ET-20 and ET-21) at stations Zhongshan and Changcheng in the Antarctic, respectively. The standard deviations of the determined amplitude factors of the main tidal waves are better than 0.5%. The amplitude of each tidal wave observed at station Zhongshan is much less than that of the same wave at station Changcheng. The differences of amplitude factors in the diurnal band (O1) at these two stations are less than 7% while those in the semi-diurnal band (M2) are larger than 40%. The influences of meteorology factors, such as atmospheric pressure and temperature, on the tidal gravity observations are very obvious. The oceanic loading effects on the tidal gravity are also very prominent. It is found that the amplitude of the final residual vector of every tidal wave reduces significantly after oceanic correction based on the Schwiderski's global co-tides. However, because the local oceanic loading is not taken into account, the discrepancies of amplitude factors of wave O1 observed at Zhongshan from the corresponding values of theoretical tidal model are about 4%, and 9% at Changcheng.

关键词： stations Zhongshan and Changcheng Antarctic tidal gravity observations international tidal gravity reference values theoretical tidal model P223.9