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The dehydration dynamics of a model cell membrane induced by cholesterol analogue 6-ketocholestanol investigated using sum frequency generation vibrational spectroscopy

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Science China Chemistry 2015年第7期58卷 1176-1186页

作者： Sulan ma Kangzhen Tian Shuji ye Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical Physics University of Science and Technology of China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China

Dehydration of a surface is the first step for the interaction between biomolecules and the surface. In this study, we systemati- cally investigated the influence of cholesterol analog 6-ketocholestanol （6-KC） on the dehydration of model cell membrane, using sum frequency generation vibrational spectroscopy. In pure DI water environment, two separate dehydration dynamic components were observed in neutrally charged and isotopically labeled 1,2-dimyristoyl-sn-glycero-3-phosphocholine （DMPC） and positively charged 1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine（chloride salt）（DMEPC） bilayer： a large-amplitude fast component and a small-amplitude slow component, which originated from the water molecules with a weak and a strong water-membrane bound strengths, respectively. Dehydration of a negatively charged mixed DMPC/DMPG bilayer lead to the membrane-bound water being reorganized to ordered structures quickly. It is evident that the water-membrane bound strengths depend largely on the charge status of the lipid and has an order of neutrally charged membrane〈〈positively charged mem- brane〈〈negatively charged membrane. In an ionic environment, KC1 solution can not only dehydrate DMPC bilayer, but also prevent the 6-KC fiom further dehydrating this model cell membrane. We observed that the dehydration dynamics behavior of DMPC bilayer in the presence of the chaotropic anions is similar to that of the negatively charged DMPG bilayer because of the penetration of chaotropic anions into the DMPC bilayer. The degree of dehydration difficulty in kosmotropic anions fol- lows a Hofmeister series and linearly correlates with the hydration Gibbs free energy of the anions. Our results provide a molecular basis for the interpretation of the Hofmeister effect of kosmotropic anions on ion transport proteins.

关键词： membrane dehydration sum frequency generation membrane-bound water membrane dipole potential Hofmeistereffect

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Activated rat hepatic stellate cells influence Th1/Th2 profile in vitro

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World Journal of Gastroenterology 2015年第23期21卷 7165-7171页

作者： Zhi-Zhi Xing Liu-ye Huang Cheng-Rong Wu hong You hong ma Ji-Dong Jia Department of Gastroenterology Yantai Yuhuangding Hospital Affiliated to Medical College of Qingdao University Liver Research Center Beijing Friendship Hospital Capital Medical University

AIM: To investigate the effects of activated rat hepatic stellate cells(HSCs) on rat Th1/Th2 profile in ***: Growth and survival of activated HSCs and CD4+ T lymphocytes cultured alone or together was assessed after 24 or 48 h. CD4+ T lymphocytes were then cultured with or without activated HSCs for 24 or 48 h and the proportion of Th1 [interferon(IFN)-γ+] and Th2 [interleukin(IL)-4+] cells was assessed by flow cytometry. Th1 and Th2 cell apoptosis was assessed after 24 h of co-culture using a caspase-3 staining procedure. Differentiation rates of Th1 and Th2 cells from CD4+ T lymphocytes that were positive for CD25 but did not express IFN-γ or IL-4 were also assessed after 48 h of co-culture with activated HSCs. Galectin-9 expression in HSCs was determined by immunofluorescence and Western blotting. ELISA was performed to assess galectin-9 secretion from activated ***: Co-culture of CD4+ T lymphocytes with activated rat HSCs for 48 h significantly reduced the proportion of Th1 cells compared to culture-alone conditions(-1.73% ± 0.71%; P < 0.05), whereas the proportion of Th2 cells was not altered; the Th1/Th2 ratio was significantly decreased(-0.44 ± 0.13; P < 0.05). In addition, the level of IFN-γ in Th1 cells wasdecreased(-65.71 ± 9.67; P < 0.01), whereas the level of IL-4 in Th2 cells was increased(82.79 ± 25.12; P < 0.05) by co-culturing, as measured by mean fluorescence intensity by flow cytometry. Apoptosis rates in Th1(12.27% ± 0.99%; P < 0.01) and Th2(1.71% ± 0.185%; P < 0.01) cells were increased 24 h after co-culturing with activated HSCs; the Th1 cell apoptosis rate was significantly higher than in Th2 cells(P < 0.01). Galectin-9 protein expression was significantly decreased in HSCs only 24 h after coculturing(P < 0.05) but not after 48 h. Co-culture for 48 h significantly increased the differentiation of Th1 and Th2 cells; however, the increase in the proportion of Th2 cells was significantly higher than that of Th1 cells(1.85% ± 0.4

关键词： Hepatic stellate cells Th1 cells Th2 cells Galectin-9

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Multilevel air quality evolution in Shenyang:Impact of elevated point emission reduction

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Journal of Environmental Sciences 2022年第3期34卷 300-310页

作者： Xiaolan Li Guiqian Tang Liguang Li Weijun Quan Yangfeng Wang Ziqi Zhao Ningwei Liu ye hong Yanjun ma Institute of Atmospheric Environment China Meteorological AdministrationNo.388 Changbai South RoadShenyangLiaoning 110166China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Environmental Meteorology Forecast Center of Beijing-Tianjin-Hebei Beijing 100089China

Visibility observed at different altitudes is favorable to understand the causes of air *** conducted 4-years of observations of visibility at 2.8 and 60 m and particulate matter(PM)concentrations from 2015 to 2018 in Shenyang,a provincial city in Northeast *** results indicated that visibility increased with the increasing height in winter(especially at night),and decreased with height in summer(especially at the daytime).PM concentration exhibited opposite vertical variation to visibility,reflecting that visibility de-grades with the increase of aerosol concentration in the *** radiosonde meteorological data showed that weak turbulence in the planetary boundary layer(PBL)in winter favored aerosols'accumulation near the *** in summer,unstable atmospheric con-ditions,upper-level moister environment,and regional transport of air pollutants resulted in the deterioration of upper-level ***-annual variation in the two-level visibility indicated that the upper-level visibility improved more significantly than low-level visibil-ity,much likely due to the reduction in emission of elevated point sources in *** study suggested that strengthening the control of surface non-point emissions is a promis-ing control strategy to improve Shenyang air quality.

关键词： Aerosol pollution Atmospheric visibility Planetary boundary layer Northeast China Vertical evolution

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Neuroprotective effect of angiotensin Ⅱ type 2 receptor during cerebral ischemia/reperfusion

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Neural Regeneration Research 2016年第7期11卷 1102-1107页

作者： Chun-ye ma Lin Yin Department of Neurology the Second Hospital of Dalian Medical University Dalian Liaoning Province China

Angiotensin Ⅱ type 2 receptor（AT2R） activation has been shown to protect against stroke,but its precise mechanism remains poorly *** investigated whether the protective effect of AT2 R against ischemia/reperfusion injury is mediated by the suppression of immune and inflammatory *** models of middle cerebral artery occlusion were intraperitoneally injected with physiological saline,the AT2 R agonist CGP42112（1 mg/kg per day） or antagonist PD123319（1 mg/kg per day）.In the CGP42112 group,AT2 R expression increased,the infarct area decreased,interleukin-1β and tumor necrosis factor-α expression decreased,and interleukin-10 expression increased compared with the saline *** AT2 R using PD123319 produced the opposite *** results indicate that AT2 R activation suppresses immune and inflammatory responses,and protects against cerebral ischemia/reperfusion injury.

关键词： interleukin protective saline occlusion infarct understood suppression injected poorly physiological

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Substrate bias effects in p-channel GaN-on-Si transistors

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Science China(Information Sciences) 2025年第1期68卷 404-405页

作者： Mengyao ZHAO Jie ma Lanlan YANG Chuanqi PAN Denggui WANG Jianjun ZHOU Sheng LI Jiaxing WEI Long ZHANG Siyang LIU Weifeng SUN National ASIC System Engineering Research Center School of Integrated Circuits Southeast University National Center of Technology Innovation for Electronic Design Automation Southeast University National Key Laboratory of Solid-State Microwave Devices and Circuits

The drain current （ID） of the n-channel GaN field-effecttransistor （n-FET） is influenced by the substrate-to-source bias voltage (VBS)（substrate bias effect）[1].Actually,nonzero VBSis also likely to occur in p-FET in real application,because the source electrode of p-FET is usually connected to high *** study reports the dependency between IDand VBSin p-FET for the first time,and analyzes the underlying mechanisms from the perspective of vertical electric field （EF） distribution.

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Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development

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Neural Regeneration Research 2025年第3期20卷 900-912页

作者： Baoqi Hu Rui Wang Hanyue Zhang Xiou Wang Sijia Zhou Bo ma Yan Luan Xin Wang Xinlin Chen Zhichao Zhang Qianyan Kang Department of Ophthalmology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi ProvinceChina Department of Ophthalmology The First Affiliated Hospital of Northwest UniversityXi’anShaanxi ProvinceChina Institute of Neurobiology Xi’an Jiaotong University Health Science CenterXi’anShaanxi ProvinceChina

The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell ***,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development ***,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo *** this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in ***,we used SOX2 and PAX6 immunostaining to identify retinal progenitor *** then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,***-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between ***,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,*** timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant *** study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina *** findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation.

关键词： bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells

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Nuclear phylogenomics of angiosperms and insights into their relationships and evolution

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Journal of Integrative Plant Biology 2024年第3期66卷 546-578页

作者： Guojin Zhang hong ma College of Life Sciences Hunan Normal UniversityChangsha 410081China Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA

Angiosperms(flowering plants) are by far the most diverse land plant group with over 300,000 species. The sudden appearance of diverse angiosperms in the fossil record was referred to by Darwin as the “abominable mystery,”hence contributing to the heightened interest in angiosperm evolution. Angiosperms display wide ranges of morphological, physiological,and ecological characters, some of which have probably influenced their species richness. The evolutionary analyses of these characteristics help to address questions of angiosperm diversification and require well resolved phylogeny. Following the great successes of phylogenetic analyses using plastid sequences,dozens to thousands of nuclear genes from next-generation sequencing have been used in angiosperm phylogenomic analyses, providing well resolved phylogenies and new insights into the evolution of angiosperms. In this review we focus on recent nuclear phylogenomic analyses of large angiosperm clades, orders, families,and subdivisions of some families and provide a summarized Nuclear Phylogenetic Tree of Angiosperm Families. The newly established nuclear phylogenetic relationships are highlighted and compared with previous phylogenetic results. The sequenced genomes of Amborella,Nymphaea, Chloranthus, Ceratophyllum, and species of monocots, magnoliids, and basal eudicots, have facilitated the phylogenomics of relationships among five major angiosperms clades. All but one of the 64 angiosperm orders were included in nuclear phylogenomics with well resolved relationships except the placements of several orders. Most families have been included with robust and highly supported placements, especially for relationships within several large and important orders and ***, we examine the divergence time estimation and biogeographic analyses of angiosperm on the basis of the nuclear phylogenomic frameworks and discuss the differences compared with previous analyses. Furthermore,we discuss the implicatio

关键词： angiosperms evolution flowering plants nuclear gene phylogenomics phylogeny

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DEVELOPMENT OF A SHAPE-SHIFTING MOBILE ROBOT FOR URBAN SEARCH AND RESCUE

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Chinese Journal of Mechanical Engineering 2008年第2期21卷 31-35页

作者： ye Changlong ma Shugen LI Bin School of machinery and Automobile Shenyang Institute of Aeronautical Engineering Shenyang 110034 China Robotic Laboratory Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China Center for Promotion of COE Program Ritsumeikan University Shiga-ken 525-8577 Japan Robotic Laboratory Shenyang Institute of Automation Chinese Academy of Sciences Shenyang110016 China Robotic Laboratory Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China

A portable shape-shifting mobile robot system named as Amoeba Ⅱ（A-Ⅱ） is developed for the urban search and rescue application. It is designed with three degrees of freedom and two tracked drive systems. This robot consists of two modular mobile units and a joint unit. The mobile unit is a tracked mechanism to enforce the propulsion of robot. And the joint unit can transform the robot shape to get high environment adaptation. A-Ⅱ robot can not only adapt to the environment but also change its body shape according to the locus space. It behaves two work states including the linear state （named as I state） and the parallel state （named as Ⅱ state）. With the linear state the robot can climb upstairs and go through narrow space such as the pipe, cave, etc. The parallel state enables the robot with high mobility on rough ground. Also, the joint unit can propel the robot to roll in sidewise direction. Two modular A-Ⅱ robots can be connected through jointing common interfaces on the joint unit to compose a stronger shape-shifting robot, which can transform the body into four wheels-driven vehicle. The experimental results validate the adaptation and mobility of A-Ⅱ robot.

关键词： Urban search and rescue Modular-unit Shape-shifting robot Environment adaptation

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Study on methanol synthesis from coal-based syngas

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Journal of Coal Science & Engineering(China) 2009年第1期15卷 98-103页

作者： ma hong-fang YING Wei-yong FANG Ding-ye State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China

The intrinsic kinetic models of the Langmuir-Hinshelwood type were investigated in terms of the reaction rates of CO hydrogenation and CO_2 hydrogenation in theform of reactant fugacity. The parameters were estimated by the Universal Global Optimization using the marquardt method. Residual error distribution and statistic tests show thatthe intrinsic kinetic models are reliable and acceptable. The mathematic model of a combined converter formed by gas-cooled and water-cooled reactor was developed and thegas-cooled reactor and the water-cooled reactor were characterized with one-dimensionalmathematic model. The distributions of temperature and concentration in the catalytic bedof the gas-cooled reactor and the water-cooled reactor in a combined converter with ayield of 1.2 Mt/a were simulated. The parallel cross linking pore model was used to describe the transfer process of multi-component diffusion system in the catalyst. The calculated value computed by the internal diffusion efficiency factor calculation model established for methanol synthesis catalyst fit the experimental value very well.

关键词： methanol coal-based syngas kinetics diffusion

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Uncertainty in TC maximum Intensity with Fixed Ratio of Surface Exchange Coefficients for Enthalpy and Momentum

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Journal of Meteorological Research 2022年第1期36卷 128-139页

作者： Hexin ye Zhanhong ma Jianfang FEI College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410005

The classical tropical cyclone(TC)maximum intensity theory of Emanuel suggests that the maximum azimuthal wind of TC depends linearly on the ratio of surface exchange coefficients for enthalpy and momentum(C_(k)and C_(d)).In this study,a series of sensitivity experiments are conducted with the three-dimensional Cloud Model 1(CM1),by fixing the ratio of C_(k)/C_(d)but varying the specific values of C_(k)and C_(d)*** results show significant variations in the simulated TC maximum intensity by varying C_(k)and C_(d),even if their ratio is ***,the maximum intensity increases steadily with increasing C_(k)and C_(d)when their value is smaller than 1.00×10^(-3),and then this increasing trend slows down with further increases in the *** previous theoretical frameworks—one based on gradient wind balance and the other incorporating the unbalanced terms-are applied to calculate the maximum potential intensity(PI).The calculated value of the former shows little variation when varying the specific values of C_(k)and C_(d),while the latter shows larger values with increases in both C_(k)and C_(d).Further examination suggests that the unbalanced effect plays a key role in contributing to the increasing intensity with increasing C_(k)and C_(d).

关键词： tropical cyclone maximum intensity surface exchange coefficients unbalanced effect

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