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Chinese Journal of Polymer Science 2024年第12期42卷 1948-1956,I0009页

作者： Nan Tian yi-Qing Li hong-yi gan Zhen-Bo Ning Ni Jiang Zhi-Hua gan State Key Laboratory of Organic-inorganic Composites Beijing Laboratory of BiomaterialsCollege of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing100029China Institute of Material Sinopec Beijing Research Institute of Chemical IndustryBeijing100013China

Star-shaped poly(lactic acid)s(PLAs)with two to five arms were synthesized by ring opening polymerization using tin(II)2-ethylhexanoate as catalyst and polyols as *** effects of molecular weight together with multi-arm architecture on crystallization behavior,spherulite morphology and alkaline degradation behavior of star-shaped PLAs have been *** results indicate that the multi-arm architecture interfered with spherulite growth,but promoted nucleation and alkaline degradation of star-shaped ***,with the increase of molecular weight(M_(n)),the crystallization rate first increased and then decreased,while the alkaline degradation rate was the *** characteristic crystallization and alkaline degradation behavior of star-shaped PLAs were discussed based on the competition between segmental mobility and central core confinement.

关键词： Star-shaped poly(lactic acid) Crystallization Spherulite morphology Alkaline degradation

Theoretical analysis of the electric potential and the electrostatic dust transport around the Shackleton crater in the Lunar south pole region

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Science China Earth Sciences 2023年第10期66卷 2278-2286页

作者： Chengxuan ZHAO hong gan Lianghai XIE yi WANG Yongjun WANG Jingyan hong Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsChina Academy of Space TechnologyLanzhou730000China Space Environment and Payload Engineering Center Lanzhou Institute of PhysicsChina Academy of Space TechnologyLanzhou730000China Deep Space Exploration Laboratory Hefei230026China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing100190China Joint Research and Development Center of Chinese Science Academy and Shen County Liaocheng252400China School of Transportation Lanzhou Jiaotong UniversityLanzhou730000China

In recent years,the Lunar south pole region(SPR)has become the focus of future explorations due to its special illumination condition and the possible water ice in permanently shadowed craters around *** Shackleton crater locates almost exactly at the Moon’s south pole and has become the hottest destination for several landing missions,including the Chang’E-7 ***,people still know little about the electric potential and the dust environment around this *** this paper,we develop an analytical model to study the surface potential and the electrostatic dust transport around the *** is found that the crater’s floor can be negatively charged due to the topographic shielding,and the surface potential is as low as-175 V on the leeward crater ***,a large number of charged dust grains can be emitted from the leeward crater wall,with a maximum height of about 10 km and a horizontal distance of about 40 km,which brings a local dust cloud around the *** the topographic shielding and the local dust cloud are qualitatively verified by a numerical simulation,in which a typical dust density of 10^(4)-10^(5)m^(-3)is found near the *** results are important to the environmental assessment for future explorations near the ***,the results are helpful to understand the surface charging and the electrostatic dust transport on the other airless bodies.

关键词： Lunar south pole Lunar crater Solar wind plasma Lunar dust Surface charging

Gastric duplication cyst mimicking large cystic lymphangioma in an adult: A rare case report and review of the literature

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World Journal of Clinical Cases 2019年第15期7卷 2087-2093页

作者： Fang-yi Xv Alex Sun yi gan hong-Jie Hu Department of Radiology Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina Diagnostic Radiology-Musculoskeletal Imaging University of CaliforniaSan DiegoCA 92093United States Department of Pathology Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Gastric duplication cysts(GDCs)are a relatively uncommon congenital developmental abnormality,mainly occurring in infants but very rarely in *** of the variability in clinical presentation,it is often quite challenging to diagnose GDCs in *** are presenting a case report of an adult diagnosed operatively as having a GDC with a literature review to summarize clinical and imaging features and the treatment selections of GDCs in adults so that doctors could have a comprehensive understanding of this disease and make a precise diagnosis and a suitable therapeutic decision for *** SUMMARY A 51-year-old man presented with recurrent epigastric pain and fullness for two *** significant findings were noted during physical examination and routine blood tests were *** abdominal ultrasound revealed a large cyst in the upper left abdominal quadrant.A following contrast-enhanced abdominal computed tomography(CT)scan demonstrated a hypodense cystic lesion between the spleen and *** lesion had scattered calcification in the cyst wall without any significant *** lesion was initially thought to be a cystic *** patient underwent a surgical resection and intraoperatively it was noted that the lesion was closely adherent to the greater curvature of the ***,a resection of the gastric mass along with a partial gastrectomy was *** patient recovered quickly with a complete symptomatic relief and did not show any further complications during the 8-month *** GDCs are quite rare in adults,with a multitude of symptoms,which is quite challenging for precise diagnosis before histological *** imaging techniques involving CT,magnetic resonance imaging,and endoscopic ultrasound could provide valuable morphological features for differential diagnosis.

关键词： Gastrointestinal abnormality Gastric duplication cyst Computed tomography Ultrasound Magnetic resonance imaging Case report

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慢性肠道炎症促进肝癌的发展

中国比较医学杂志 2015年第5期25卷 1-4,I0001,F0002页

作者：易宏淦臧梦雅吴志远朱正赵新明王维虎曲春枫广州医科大学广州510182 中国医学科学院肿瘤医院分子肿瘤学国家重点实验室北京100021 中国医学科学院肿瘤医院影像诊断科北京100021 中国医学科学院肿瘤医院放射治疗科北京100021

目的探讨慢性肠道炎症状态下菌群结构及构成改变对肝癌进展的影响。方法 22只雄性乙肝病毒转基因小鼠在出生后第2周腹腔注射二乙基亚硝胺诱导小鼠原发性肝癌,随机分为慢性肠炎组(给予含2%葡聚糖硫酸钠的饮用水)和对照组(给予正常饮用水... 详细信息

目的探讨慢性肠道炎症状态下菌群结构及构成改变对肝癌进展的影响。方法 22只雄性乙肝病毒转基因小鼠在出生后第2周腹腔注射二乙基亚硝胺诱导小鼠原发性肝癌,随机分为慢性肠炎组(给予含2%葡聚糖硫酸钠的饮用水)和对照组(给予正常饮用水)。上述小鼠观察至22周龄。在此期间定期进行肝功能测定,收集粪便进行宏基因组测序。另将4只已发生肝癌的小鼠与7只8周龄肉眼及病理学未见肝癌的小鼠同笼(分2笼)饲养16周。结果 DSS所诱导的慢性肠炎小鼠与正常饮用水小鼠相比肝功能无显著改变;DSS诱导的慢性肠炎组小鼠(n=10)在第22周龄时有9只发生弥漫性肉眼可见的肝癌,而正常饮用水小鼠(n=12)仅有2只发生肝癌,肿瘤发生率(P=0.002)和肿瘤数量(P=0.028)有显著差别;与正常饮用水小鼠相比,慢性肠炎组小鼠肠道菌群中,普雷沃氏菌属(P=0.022)和厌氧支原体属(P=0.014)显著减少;与已发生肝癌小鼠进行同笼饲养的小鼠(n=7)在24周龄时全部发生肉眼可见的肝癌。结论慢性肠道炎症状态下,肠道菌群改变可促进肝癌进展。

关键词：慢性肠道炎症肝癌菌群改变

Charged Higgs Boson Pair Production via Gluon-Gluon Collisions in MSSM with CP Violation

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Communications in Theoretical Physics 2001年第7期36卷 61-64页

作者： JIANG yi MA Wen-gan HAN Liang HOU hong-Sheng CCAST(World Laboratory) P.O.Box 8730Beijing 100080China Modern Physics Department University of Science and Technology of ChinaHefei 230027China

The CP-violating effects to the subprocess gg→H+H-are studied in the mSUGRA scenario at the CERN large hadron collider,by taking into account the experimental bounds of electron and neutron electric dipole *** CP-violating effects in this process are related to the complex phases ofμand Af in the mSUGRA *** our calculation we consider smallCP phases ofμand Af and neglect the effects of neutral Higgs boson *** this case the CP effects to the process mainly come from the complex couplings of *** find a strong dependence of charged Higgs boson pair production rate on the complex couplings in the parameter space of minimal supersymmetric standard model.

关键词： charged Higgs boson MSSM CP violation

Carbon-based materials for electrochemical dechlorination

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Nano Research 2023年第11期16卷 12543-12557页

作者： Guoqiang gan Guo hong Wenjun Zhang Center of Super-Diamond and Advanced Films(COSDAF) Department of Materials Science and EngineeringCity University of Hong KongHong Kong 999077China School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China

Electrochemical dechlorination reaction(EDR)is a promising,environmentally friendly,and economically profitable technology for treating chlorinated organic *** efficient environmental protection,electrocatalysts with high stability and low cost are of extremely significance to the development of EDR ***-based materials have aroused broad interest as electrocatalysts for many electrochemical reactions due to their characteristics including large specific surface area,controllable structure,good conductivity,and chemical *** EDR,the carbon-based materials also show many unique superiorities,like strong adsorption capacity to chlorinated organic compounds(COCs),excellent catalytic activity and stability,and environmental *** review starts with a detailed summary on the mechanisms of electrochemical dechlorination(direct and indirect electron transfer pathway)and factors affecting the effectiveness of *** the paper comprehensively overviews the current progresses of carbon-based materials for EDR of COCs,following their two major application scenarios,i.e.,directly as electrocatalysts and as advanced supports for other ***,the formation of different active sites in carbon-based electrocatalysts and their EDR activities are ***,the current challenges and perspectives in this field are *** review will provide an in-depth understanding for the design of advanced carbon-based materials and promote the development of EDR technology.

关键词： carbon-based electrocatalysts carbon supports electrochemical dechlorination chlorinated organic compounds mechanism active sites

Control on the Morphology of ABA Amphiphilic Triblock Copolymer Micelles in Dioxane/Water Mixture Solvent

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Chinese Journal of Polymer Science 2018年第6期36卷 728-735页

作者： Yuan gan Zhi-Da Wang Zhuo-Xin Lu Yan Shi hong-yi Tan Chang-Feng Yan Key Laboratory of Renewable Energy Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640China Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

This work offers a typical understanding of the factors that govern the nanostructures of poly（4-vinyl pyridine）-b-polystyrene-bpoly（4-vinyl pyridine）（P4 VP-b-PS-b-P4 VP） block copolymers（BCs） in dioxane/water, in which water is a selective solvent for the P4 VP block. It is achieved through an investigation of the amphiphilic triblock copolymer micelles by variation of three different factors, including water content（above CWC but under the immobile concentration）, temperature（ranging from 20 °C to 80 °C）, and copolymer composition（low and high PS block length）. Transition of bead-like micelles to vesicles is observed with the increase of water content due to the increase of interfacial energy between the copolymer and the solvent. Effect of temperature superposed on that of water content results in various morphologies, such as beads, fibers, rods, capsules, toroids, lamellae, and vesicles. The interfacial tension between the BC and the solvent increases with the increase of water content but decreases with the increase of temperature, indicating that the micellar morphologies are resulted from the competitive interplay between the temperature and the water content and always change in a direction that decreases the interfacial energy. Based on the micellar structures obtained in this work and the effects of temperature superposed on water concentration, a diagram of phase evolution of different micellar morphologies is illustrated here, covering the temperature range from 20 °C to 80 °C and the water content changing from 20 vol% to 35 vol%. For the investigation of BC composition, morphological transition of vesicle-to-fiber, for high PS length, is observed as compared with bead-to-capsule for low PS length, as the temperature changes from 20 °C to 80 °C. Our research complements the protocols to control over the morphologies and the phase diagram describing P4 VP-b-PS-b-P4 VP micellar nanostructures in aqueous solution.

关键词： Micelles Morphological control Self-assembly Block copolymer

On the density of Birkhoff sums for Anosov diffeomorphisms

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Science China Mathematics 2022年第2期65卷 319-330页

作者： Shaobo gan yi Shi Mingyang Xia School of Mathematical Sciences Peking UniversityBeijing 100871China

Let f : M → M be an Anosov diffeomorphism on a nilmanifold. We consider Birkhoff sums for a Holder continuous observation along periodic orbits. We show that if there are two Birkhoff sums distributed at both sides o... 详细信息

关键词： Anosov diffeomorphism Birkhoff sum periodic point nilmanifold

THF_1 mutations lead to increased basal and wound-induced levels of oxylipins that stimulate anthocyanin biosynthesis via COI_1 signaling in Arabidopsis

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Journal of Integrative Plant Biology 2014年第9期56卷 916-927页

作者： yi gan hong Li Ye Xie Wenjuan Wu Maoyin Li Xuemin Wang Jirong Huang National Key Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and EcologyShanghai Institutes for Biological Sciencesthe Chinese Academy of Sciences School of Agricultural and Food Science Zhejiang A&F University Department of Biology University of Missouri Donald Danforth Plant Science Center

Mutants defective in chloroplast development or photosynthesis are liable to accumulate higher levels of anthocyanin in photo-oxidative ***,regulatory mechanisms of anthocyanin biosynthesis in the mutants remain ***,we investigated the mechanism by which the deletion of thylakoid formation1（THF1） leads to an increased level of anthocyanin in Arabidopsis thaliana *** and genetic evidence showed that the increased level of anthocyanin in thf1 is dependent on coronatine-insensitive1（COM）*** data showed that thf1 had higher levels of basalα-linolenic acid（α-LeA）,and methyl jasmonate（JA）-induced α-LeA and 12-oxophytodienoic acid（OPDA） than the wild type（WT）.Consistently,expression levels of phospholipase genes including pPLAIIα and PLA-Iγ1 were elevated in ***,inhibition of lipase activity by bromoenol lactone,a specific inhibitor of plant pPLA,led to producing identical levels of anthocyanins in WT and thf1 ***,OPDA biosynthesis was triggered by light illumination in isolated chloroplasts,indicating that new protein import into chloroplasts is not required for OPDA ***,we conclude that the elevated anthocyanin accumulation in thf1 is attributed to an increase in JA *** JA-mediated signaling to coordinate plant metabolism and growth in stress may be conserved in other photosensitive mutants.

关键词： Anthocyanin Arabidopsis jasmonates photo-oxidative stress retrograde signaling THF1

N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： yi Zhang Hui Cai Xiuhai gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis