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Geometry, Electronic Structure, and Related Properties of Dye Sensitizer： 3,4-bis[1- （carboxymethyl）-3-indolyl]- 1 H-pyrrole-2,5-dione

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Chinese Journal of Chemical Physics 2009年第1期22卷 63-68页

作者： Cai-rong Zhang You-zhi Wu Yu-hong chen Yu-tian Ding Ding-jun Zhang hong-shan chen Department of Applied Physics Lanzhou University of Technology Lanzhou 730050 China School of Material Science and Engineering Lanzhou University of Technology Lanzhou 730050 China College of Physics and Electronic Engineering Northwest Normal University Lanzhou 730070 China

The geometry, electronic structure, polarizability and hyperpolarizability of dye sensitizer 3,4-bis[1-（carboxymethyl）-3-indolyl]-1H-pyrrole-2,5-dione （BIMCOOH） were studied using density functional theory （DFT） with hybrid functional B3LYP, and the electronic absorption spectra were investigated using semi-empirical quantum chemical method ZINDO-1 and time-dependent DFT （TDDFT）. The results of natural bond orbital suggest that the natural charges of the dione, indole, and acetic groups are about 0.15e, -0.29e, and 0.44e, respectively. The calculated isotropic polarizability, polarizability anisotropy invariant and hyperpolarizability are 305.4, 188.3, and 1155.4 a.u., respectively. The electronic absorption spectral features in visible and near-UV region were assigned to the π→π^＊ transition due to the qualitative agreement between the experiment and the TDDFT calculations, and the transitions of the excited states 9-11 related to photoinduced intramolecular charge transfer processes. The analysis of electronic structure and UV-Vis absorption indicates that the indole groups primarily contributed sensitization of photo-to-currency conversion processes, and the interracial electron transfer between semiconductor TiO2 electrode and dye sensitizer BIMCOOH are electron injection processes from excited states of the dyes to the semiconductor conduction band.

关键词： Dye sensitizer Electronic structure Density functional theory Absorption spectrum

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Chemical Composition and Biological Activities of Essential Oil from the Rhizomes of Iris bulleyana

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Agricultural Sciences in China 2009年第6期8卷 691-696页

作者： DENG Guo-bin ZHANG Han-bo XUE hong-fen chen shan-na chen Xiao-lan Department of Biology Yunnan University Kunming 650091 P.R.China

Iris bulleyana has long been used as a remedy for detoxication and detumescence. Hydrodistillation was used to extract the essential oil from its rhizomes, and 0.23% oil yield was obtained. Using gas chromatography-mass spectrometry （GC- MS） analysis, 31 chemicals including aristolone, cuparene, β-gurjunene, δ-amorphene, α-muurolene, α-cadinol, camphor, γ-elemene, and τ-cadinol were identified. The essential oil exhibited antibacterial activity against Acetobacter calcoacetica, Bacillus subtillis, Clostridium sporogenes, Clostridium perfringens, Escherichia coli, Salmonella typhii, Staphylococcus aureus, and Yersinia enterocolitica. Its antifungal and antioxidant activities were also tested.

关键词： Iris bulleyana essential oil antibacterial antifungal antioxidant GC-MS chemical components

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Tailoring the texture and mechanical properties of 3%Y_(2)O_(3)p/ZGK200 composites fabricated by unidirectional and cross rolling followed by annealing

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Journal of Magnesium and Alloys 2024年第4期12卷 1479-1495页

作者： Xihai Li hong Yan Zhiwei shan Rongshi chen Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China Center for Advancing Materials Performance from the Nanoscale(CAMP-Nano)and Hysitron Applied Research Center in China(HARCC) State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049China

3%Y_(2)O_(3)p/ZGK200 composites were subjected to unidirectional rolling(UR)and cross rolling(CR)at 400℃and 350℃followed by annealing at 300℃for 1 *** microstructure,texture and mechanical properties of rolled and annealed composites were systematically *** rolled composites exhibited a heterogeneous microstructure,consisting of deformed grains elongated along rolling direction(RD)and Y_(2)O_(3)particles bands distributed along *** annealing,static recrystallization(SRX)occurred and most deformed grains transformed into equiaxed grains.A non-basal texture with two strong T-texture components was obtained after UR while a non-basal elliptical/circle texture with circle multi-peaks was obtained after CR,indicating that rolling path had great influences on texture of the *** annealing process,R-texture component disappeared or weakened,as results,a non-basal texture with double peaks tilting from normal direction(ND)to transverse direction(TD)and a more random non-basal texture with circle multi-peaks were obtained for UR and CR composites,*** yield strength of rolled composites after UR showed obvious anisotropy along RD and TD while a low anisotropic yield strength was obtained after *** Y_(2)O_(3)particles broke during *** fracture of the composites was attributed to the existence of Y_(2)O_(3)clusters and interfacial debonding between particles and matrix during tension,as a result,the ductility was not as superior as matrix alloy.

关键词： Magnesium matrix composites Unidirectional rolling Cross rolling Texture Mechanical properties

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Human influence on the duration of extreme temperature events in Asia's hotspot regions

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Advances in Climate Change Research 2024年第2期15卷 312-326页

作者： Zi-Meng WANG hong-Yun MA Wei LI Hai-shan chen Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Nanjing University of Information Science and TechnologyNanjing 210044China

Observations and models indicate that human activities exert a considerable impact on the frequency and intensity of extreme temperature events,which are associated with global ***,changes in the duration of extreme temperature events and their association with human influence have not been considered in most ***,the possible relationship between the observed changes in the warm and cold spell duration(WSDI and CSDI)in hotspot regions during 1960-2014 and human influence was investigated based on the NCEP/NCAR reanalysis version 1 and Coupled Model Inter-comparison Project Phase 6(CMIP6)*** projection based on these attribution results was also *** optimal fingerprinting technique was used to compare observed changes in WSDI and CSDI to simulated changes averaged across eight CMIP6 *** show that anthropogenic(ANT)forcing contributed to the observed increase in WSDI in the three hotspot regions(West Asia,South Asia and Southeast Asia),with the majority of the changes being attributed to greenhouse gas ***,a generally weak ANT signal can be observed in the decreasing trend of CSDI and can be detected in South and Southeast *** influence of aerosol forcing remains undetected in either WSDI or CSDI,which differs from the results for frequency and intensity of extreme *** attribution results revealed that the constrained projection of WSDI is lower than the raw projection for 2015-2100 in West Asia and Southeast ***,no differences in future CSDI changes are found in Southeast Asia between the constrained and raw projections.

关键词： Extreme temperature events Duration Detection attribution Constraint projection Hotspot regions

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Synthesis of Novel Non-Nucleoside HIV-1 Reverse Transcriptase Inhibitors-1-(3-Phthalimido-2-oxobutyl)-4-Substituted-phenylpiperazines

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Chinese Chemical Letters 2000年第7期11卷 571-572页

作者： Xin chen Lin WANG Zhi Zhong ZHAO Xing Quan ZHANG Xiang hong chen hong shan chen(Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050 Institute of Medicinal Biotechnology, Chinese Academy of M Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

We have designed and synthesized a series of new phthalimidopiperazines, biological activity test show that the target compounds(Ic, Ie, ii) can inhibit HIV-I RT with IC50 20.0, 43.8, and 63.7 mu M, respectively.

关键词： piperazine phthalimide HIV1-RT inhibitor

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Mutations outside the YMDD motif in the P protein can also cause DHBV resistant to Lamivudine

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World Journal of Gastroenterology 2005年第27期11卷 4261-4267页

作者： Jin-Yang He Yu-Tong Zhu Rui-Yi Yang Li-Ling Feng Xing-Bo Guo Feng-Xue Zhang hong-shan chen Tropical Medicine Institute of Guangzhou University of Traditional Chinese Medicine Guangzhou 510405 Guangdong Province China Institute of Medical Biotechnology of CAMS and PUMC Beijing 100050 China

AIM: To observe the Lamivudine resistance character of a DHBV strain in vitro and in vivo, and to analyze if the Lamivudine resistance character is caused by gene mutation or by abnormity of the Lamivudine ***: Congenitally DHBV-negative Guangdong brown ducks and duck embryo liver cells were respectively taken as animal and cell model. The Lamivudine-susceptive DHBV and Lamivudine-resistant DHBV (LRDHBV) were infected and Lamivudine was administrated according to the divided groups. The changes of DHBV quantity in the animal and cell model were tested. Three Lamivudineresistant and two Lamivudine-susceptive DHBV complete genomes were successfully amplified, sequenced and then submitted to GenBank. All the DHBV complete sequences in the GenBank at present were taken to align with the three LRDHBV to analyze the mutational points related to the Lamivudine-resistant ***: Both the animal and cell model showed that the large and the small dosage Lamivudine have no significant inhibitory effect on the LRDHBV. Five sequences of DHBV complete genomes were successfully cloned. The GenBank accession numbers of the three sequences of LRDHBV are AY521226, AY521227, and AY433937. The two strains of Lamivudine-susceptive DHBV are AY392760and AY536371. The correlated mutational points are KorR86Q and AorE591T in the P ***: The Lamivudine resistance character of this DHBV strain is caused by genome mutation; the related mutational points are KorR86Q and AorE591T and have no relations with the YMDD motif mutation.

关键词： DHBV Lamivudine resistance Mutational points

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Engineered extracellular vesicles: A new approach for targeted therapy of tumors and overcoming drug resistance

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Cancer Communications 2024年第2期44卷 205-225页

作者： chen Ming-Kun chen Zi-Xian Cai Mao-Ping chen hong chen Zhuang-Fei Zhao shan-Chao Department of Urology The Third Affiliated Hospital of Southern Medical UniversityGuangzhouGuangdongP.R.China The Third Clinical College Southern Medical UniversityGuangzhouGuangdongP.R.China Luoyang Key Laboratory of Organic Functional Molecules College of Food and DrugLuoyang Normal UniversityLuoyangHenanP.R.China Department of Urology Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdongP.R.China

Targeted delivery of anti-tumor drugs and overcoming drug resistance in malig-nant tumor cells remain significant clinical ***,there are only few effective methods to address these *** vesicles(EVs),actively secreted by cells,play a crucial role in intercellular information transmis-sion and cargo *** studies have demonstrated that engineered EVs can serve as drug delivery carriers and showed promising application ***,there is an urgent need for further improvements in the isolation and purification of EVs,surface modification techniques,drug assem-bly processes,and precise recognition of tumor cells for targeted drug delivery *** this review,we summarize the applications of engineered EVs in cancer treatment and overcoming drug resistance,and current challenges asso-ciated with engineered EVs are also *** review aims to provide new insights and potential directions for utilizing engineered EVs as targeted delivery systems for anti-tumor drugs and overcoming drug resistance in the near future.

关键词： drug delivery drug resistance extracellular vesicles nanoparticles

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A whole-net cooperative positioning method based on CDGNSS and inter-vehicle ranging

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Chinese Journal of Aeronautics 2024年第2期37卷 401-416页

作者： shan HU hongbo ZHAO chen ZHUANG School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Relative positioning is recognized as an important issue for vehicles in urban ***-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ranging have attracted attention in improving the performance of baseline estimation between ***,current CP methods estimate the baselines separately and ignore the interactions among the positioning information of different *** interactions are called’information coupling’.In this work,we propose a new multivehicle precise CP framework using the coupled information in the network based on the Carrier Differential GNSS(CDGNSS)and inter-vehicle *** demonstrate the benefit of the coupled information by deriving the Cramer-Rao Lower Bound(CRLB)of the float estimation in *** fully use this coupled information,we propose a Whole-Net CP(WN-CP)method which consists of the Whole-Net Extended Kalman Filter(WN-EKF)as the float estimation filter,and the Partial Baseline Fixing(PBF)as the ambiguity resolution *** WN-EKF fuses the measurements of all baselines simultaneously to improve the performance of float estimation,and the PBF strategy fixes the ambiguities of the one baseline to be estimated,instead of full ambiguity resolution,to reduce the computation load of ambiguity *** tests involving four vehicles were conducted in urban *** results show that the proposed WN-CP method can achieve better performance and meanwhile maintain a low computation load compared to the existing methods.

关键词： GNSS Cooperative positioning Baseline Ambiguity resolution Information coupling

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How mesenchymal stem cells transform into adipocytes:Overview of the current understanding of adipogenic differentiation

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World Journal of Stem Cells 2024年第3期16卷 245-256页

作者： shan-shan Liu Xiang Fang Xin Wen Ji-shan Liu Miribangvl Alip Tian Sun Yuan-Yuan Wang hong-Wei chen Department of Reumatology and Immunology Nanjing Drum Tower HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina Department of Emergency Nanjing Drum Tower HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical EngineeringBeihang UniversityBeijing 100191China Anhui Key Laboratory of Infection and Immunity Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina

Mesenchymal stem cells(MSCs)are stem/progenitor cells capable of self-renewal and differentiation into osteoblasts,chondrocytes and *** transformation of multipotent MSCs to adipocytes mainly involves two subsequent steps from MSCs to preadipocytes and further preadipocytes into adipocytes,in which the process MSCs are precisely controlled to commit to the adipogenic lineage and then mature into *** studies have shown that the master transcription factors C/enhancer-binding protein alpha and peroxisome proliferation activator receptor gamma play vital roles in ***,the mechanism underlying the adipogenic differentiation of MSCs is not fully ***,the current knowledge of adipogenic differentiation in MSCs is reviewed,focusing on signaling pathways,noncoding RNAs and epigenetic effects on DNA methylation and acetylation during MSC ***,the relationship between maladipogenic differentiation and diseases is briefly *** hope that this review can broaden and deepen our understanding of how MSCs turn into adipocytes.

关键词： Mesenchymal stem cell Adipogenic differentiation Signaling pathway Noncoding RNA Epigenetic regulation

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Density Functional Theory Study on Organic Dye Sensitizers Containing Bis-dimethylfluorenyl Amino Benzofuran

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Chinese Journal of Chemical Physics 2009年第5期22卷 489-496,I0001页

作者： Cai-rong Zhang Zi-jiang Liu Yu-hong chen Jun Ma hong-shan chen Mei-ling Zhang State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials Lanzhou University of Technology Lanzhou 730050 China Department of Applied Physics Lanzhou University of Technology Lanzhou 730050 China Institute of Applied Physics and Computational Mathematics Beefing 100088 China Institute of Electronic Information Science and Technology Lanzhou City Universiy Lanzhou 730070 China College of Physics and Electronic Engineering Northwest Normal University Lanzhou 730070 China

The geometries, electronic structures, polarizabilities and hyperpolarizabilities, as well as the UV-Vis spectra of the two organic dye sensitizers containing bis-dimethylfluorenyl amino benzofuran were studied via density functional theory （DFT） and time-dependent DFT. The features of electronic absorption spectra were assigned on account of the agreement between the experiment and the calculations. The absorption bands in visible region are related to photoinduced electron transfer processes, and the dimethylfluorenyl amino benzo[b]furan groups are major chromophore that contributed to the sensitization of photo-to-current conversion. The role of vinylene group in geometry, electronic structure and spectra property is analyzed according to the comparative study of the dyes.

关键词： Dye sensitizer Electronic structure Density functional theory Absorptionspectra

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