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Chinese Journal of Polymer Science 2001年第4期19卷 385-390页

作者： Zhong-ming Hu li-heng wu Da-cheng wu Shou-xi Chen State Key Laboratory of Polymer Physics and Chemistry, Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences, Beijing 100080, China China Textile Academy Beijing 100025, China Textile College, Sichuan University Chengdu 610065, China 中科院化学所高分子物理与化学国家重点实验室北京中国纺织研究院北京四川大学四川成都

The oriented chitosan films obtained from pre-sheared liquid crystalline chitosan/dichloroacetic acid (DCA) solutions were studied by means of polarized optical microscopy (POM), scanning electron microscopy (SEM), infra-red dichroism technique and wide angle X-ray diffraction (WAXD). The sheer induced band texture in the film was found to correspond to the sinusoidal fibrillar microstructure along the shearing direction on the basis of POM and SEM observations. The sinusoidal fibril was found to be lying within the film plane. The model of chitosan molecular orientation in the pre-sheared film with band texture can be established assuming that the main chain orients in the shearing direction and the side group is perpendicular to the shearing direction. The WAXD azimuthal scanning at 2 theta = 20 degrees indicates that the (002) plane orients perpendicular to the shearing direction.

关键词： chitosan morphology orientation shear induced band texture liquid crystalline solution

Stimulation and imaging of neural cells via photonic nanojets

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Photonics Research 2024年第8期12卷 1604-1609页

作者： heng li XIXI CHEN TIANli wu ZHIYONG GONG JINGHUI GUO XIAOSONG BAI JIAWEI li YAO ZHANG YUCHAO li BAOJUN li Guangdong Provincial Key Laboratory of Nanophotonic Manipulation Institute of NanophotonicsCollege of Physics&Optoelectronic EngineeringJinan UniversityGuangzhou 511443China School of Medicine The Chinese University of Hong KongShenzhen 518172China InnerMedical Co. Ltd.Shenzhen 518055China

Various neuromodulation techniques have been developed to modulate the peak activity of neurons,thereby regulating brain function and alleviating neurological ***,neuronal stimulation and imaging have significantly contributed to the understanding and treatment of these ***,we propose utilizing photonic nanojets for optical stimulation and imaging of neural *** application of resin microspheres as microlenses enhances fluorescence imaging of neural lysosomes,mitochondria,and actin filaments by generating photonic ***,optical tweezers can precisely manipulate the microlenses to locate specific targets within the cell for real-time stimulation and *** focusing capabilities of these microlenses enable subcellular-level spatial precision in stimulation,allowing highly accurate targeting of neural cells while minimizing off-target ***,fluorescent signals during neural cell stimulation can be detected in real-time using these *** proposed method facilitates investigation into intercellular signal transmission among neural cells,providing new insights into the underlying mechanisms of neuronal cell activities at a subcellular level.

关键词： stimulation neural utilizing

Productivity in the Southern Ocean Antarctic Zone during the Northern Hemisphere Glaciation(NHG)and its link to atmospheric pCO_(2)

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Science China Earth Sciences 2024年第7期67卷 2242-2252页

作者： Yiming wu Jingteng GUO Xiangyu ZHAO Wenshen XIAO heng liU Zhifang XIONG Tiegang li Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratoryof Polar Ecosystem and Climate Change Shanghai Jiao Tong UniversityMinistry of EducationShanghai 200030China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China

A decrease in atmospheric CO_(2)partial pressure(pCO_(2))is considered an important prerequisite for the onset and intensification of Northern Hemisphere Glaciation(NHG).However,how the ocean sequestered missing CO_(2)during the NHG is still *** in surface productivity and deep ventilation in the Southern Ocean(SO)have been proposed to explain the variations in atmospheric pCO_(2)over the last eight glacial cycles,but it is unclear whether these mechanisms contributed to the decrease in atmospheric pCO_(2)during the *** titanium-normalized contents and mass accumulation rates of biogenic opal and total organic carbon from the International Ocean Discovery Program(IODP)Expedition 374 Site U1524A,we reconstruct the productivity in the Ross Sea,Antarctica,from 3.3 Ma to 2.4 *** productivity records exhibit a long-term decreasing trend and several distinct phased evolutionary ***,the local productivity fluctuated dramatically during 3.3-3.0 Ma,decreased gradually during 3.0-2.6 Ma,and remained relatively constant during 2.6-2.4 *** comparing productivity with its potential influences,we infer that the phased and long-term evolutions of productivity were mainly controlled by changes in deep ocean *** ice expansion might have decreased productivity during 3.3-3.0 Ma by light *** in eolian dust input have little effect on *** analysis revealed no coupling linkage between productivity and atmospheric pCO_(2),indicating that the productivity in the SO Antarctic Zone(AZ)was not the main factor controlling the atmospheric CO_(2)decrease during the *** improve our understanding of the role of SO processes in the NHG,further studies should focus on the potential influences of deep ocean ventilation on atmospheric pCO_(2)in the AZ,and similar studies should also be extended to the sea area in the Subantarctic Zone.

关键词： Ross Sea Biogenic opal Total organic carbon Deep ocean ventilation Sea ice Ocean carbon cycle

The circadian clock in enamel development

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International Journal of Oral Science 2024年第3期16卷 371-380页

作者： Ke wu Xiaochan li Yunyang Bai Boon Chin heng Xuehui Zhang Xuliang Deng Department of Geriatric Dentistry Peking University School and Hospital of StomatologyBeijingChina 4th Division Peking University School and Hospital of StomatologyBeijingChina Department of Dental Materials&Dental Medical Devices Testing Center Peking University School and Hospital of StomatologyBeijingChina National Engineering Research Center of Oral Biomaterials and Digital Medical Devices NMPA Key Laboratory for Dental MaterialsBeijing Laboratory of Biomedical Materials&Beijing Key Laboratory of Digital StomatologyPeking University School and Hospital of StomatologyBeijingChina Oral Translational Medicine Research Center Joint Training base for Shanxi Provincial Key Laboratory in Oral and Maxillofacial Repair Reconstruction and Regeneration The First People’s Hospital of Jinzhong JinzhongChina

Circadian rhythms are self-sustaining oscillations within biological systems that play key roles in a diverse multitude of physiological *** circadian clock mechanisms in brain and peripheral tissues can oscillate independently or be synchronized/disrupted by external *** enamel is a type of mineralized tissue that forms the exterior surface of the tooth *** Retzius lines are readily observable microstructures of mature tooth enamel that indicate the regulation of amelogenesis by circadian *** enamel is formed by enamel-forming cells known as ameloblasts,which are regulated and orchestrated by the circadian clock during *** review will first examine the key roles of the circadian clock in regulating ameloblasts and *** physiological processes are involved,including gene expression,cell morphology,metabolic changes,matrix deposition,ion transportation,and ***,the potential detrimental effects of circadian rhythm disruption on enamel formation are *** rhythm disruption can directly lead to Enamel Hypoplasia,which might also be a potential causative mechanism of amelogenesis ***,future research trajectory in this field is *** is hoped that this review will inspire more intensive research efforts and provide relevant cues in formulating novel therapeutic strategies for preventing tooth enamel developmental abnormalities.

关键词： enamel crown exterior

Simulation of roof snow loads based on a multi-layer snowmelt model:Impact of building heat transfer

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Building Simulation 2024年第6期17卷 907-932页

作者： Xuanyi Zhou heng Chen Yue wu Tiange Zhang State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai200092China

To investigate the impact of building heat transfer on roof snow loads,roof snow loads and snow load thermal coefficients from 61 Chinese sites over a period of 50 years are simulated based on basic meteorological data such as temperature,humidity,wind speed,and precipitation,and a multi-layer snowmelt model considering the building heat ***,the accuracy of the multi-layer snowmelt model is validated using the data of observed ground snow load and roof snow melting *** relationship between meteorological conditions,snow cover characteristics,and thermal coefficients of snow loads in three representative sites is then ***,the characteristics of thermal coefficients in each zone are analyzed by combining them with the statistical results of meteorological data from 1960 to 2010,and the equations of thermal coefficients in different zones on indoor temperatures and roof heat transfer coefficients are fitted ***,the equations in this paper are compared with the thermal coefficients in the main snow load *** results indicate that the snowmelt model using basic meteorological data can effectively provide samples of roof snow *** the cold zone where the snow cover lasts for a long time and does not melt easily,the thermal coefficients of the snow loads on the heating buildings are lower than those in the warm zone due to the long-term influence of the heat from inside the *** coefficients are negatively correlated with indoor temperatures and roof heat transfer *** the indoor temperature is too low or the roof insulation is good,the roof snow load may exceed the ground snow *** thermal coefficients for heated buildings in the main snow load codes are more conservative than those calculated in this paper,and the thermal coefficients for buildings with lower indoor temperatures tend to be smaller.

关键词： snowmelt model roof snow load building heat transfer thermal coefficient load code

Hierarchical Silver Indium Tungsten Oxide Mesocrystals with Morphology-, Pressure-, and Temperature-Dependent Luminescence Properties

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Nano Research 2010年第6期3卷 395-403页

作者： Bo Hu li-heng wu Zhi Zhao Meng Zhang Shao-Feng Chen Shu-Juan liu Hong-Yan Shi Ze-Jun Ding Shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryDepartment of Materials Science and Engineeringthe National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Division of Instruments Center for Physical Science Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Department of Physics Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China

Highly hierarchical structures of silver indium tungsten oxide(AgIn(WO_(4))_(2))mesocrystals can be rationally fabricated via the microwave-assisted synthesis method by tuning the initial concentrations of the *** spectra of hierarchical AgIn(WO_(4))_(2) mesocrystals were measured to investigate the correlation between the morphology,pressure,and temperature and their luminescence *** materials showed interesting white emission when excited by visible light of wavelength 460 ***(WO_(4))_(2) materials having different morphologies displayed notable differences in photogenerated emission *** emission was strongly correlated with the surface nanostructures of outgrowths,with larger amounts of outgrowths leading to stronger emission *** pressure-and temperature-dependent photoluminescence properties of these materials have also been investigated under hydrostatic pressures up to 16 GPa at room temperature and in the temperature range from 10 to 300 K.

关键词： Photoluminescence AgIn(WO_(4))_(2) mesocrystal morphology high-pressure temperature

Blockade of the deubiquitinating enzyme USP48 degrades oncogenic HMGA2 and inhibits colorectal cancer invasion and metastasis

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1624-1643页

作者： Can Cheng Hanhui Yao heng li Jingwen liu Zhengyi liu Yang wu liang Zhu Hejie Hu Zhengdong Fang liang wu Department of General Surgery the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Comprehensive Surgery Anhui Provincial Cancer HospitalWest District of the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Anhui Provincial Hospital Health Management Center the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Breast Surgery Henan Provincial People's HospitalPeople's Hospital of Zhengzhou UniversityPeople's Hospital of Henan UniversityZhengzhou 450003China

HMGA2,a pivotal transcription factor,functions as a versatile regulator implicated in the progression of diverse aggressive *** this study,mass spectrometry was employed to identify ubiquitin-specific proteases that potentially interact with HMGA2,and USP48 was identified as a deubiquitinating enzyme of *** enforced expression of USP48 significantly increased HMGA2 protein levels by inhibiting its degradation,while the deprivation of USP48 promoted HMGA2 degradation,thereby suppressing tumor invasion and *** discovered that USP48 undergoes SUMOylation at lysine 258,which enhances its binding affinity to *** subsequent phenotypic screening of small molecules,we identified DUB-IN-2 as a remarkably potent pharmacological inhibitor of ***,the small-molecule inhibitor targeting USP48 induces destabilization of ***,upregulation of USP48 or HMGA2 in cancerous tissues is indicative of poor prognosis for patients with colorectal cancer(CRC).Collectively,our study not only elucidates the regulatory mechanism of DUBs involved in HMGA2 stability and validates USP48 as a potential therapeutic target for CRC,but also identifies DUB-IN-2 as a potent inhibitor of USP48 and a promising candidate for CRC treatment.

关键词： Colorectal cancer Invasion and metastasis Post-translational modification Ubiquitination SUMOylation USP48 HMGA2 Specific inhibitors

STUDIES ON THE NATURE OF THE MACROMOLECULAR CONDENSED STATE OF "NASCENT" ULTRA HIGH MOLAR MASS POLYETHYLENE

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Chinese Journal of Polymer Science 2001年第1期19卷 25-31页

作者： Zhong-yong Fan Qiang Lan Hai-shan Bu li-heng wu lin Sun Ren-yuan Qian Shou-xi Chen Yong-feng Men Bing-zheng Jiang Department of Materials Science Fudan UniversityShanghai 200433 China Textile 4cademy PO Box 651Beijing 100025 Institute of Chemistry Chinese Academy of SciencesBeijing 100080 Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022 Faculty of Physics University of Freiburg

Ultra high molar mass polyethylene(UHPE)powder as polymerized in a slurry process has been studied,in its nascent state,after recrystallization on rapid cooling from the melt and after hot compression molding to a film,by DSC,effect of annealing the recrystallized specimen at 120 similar to 130 degreesC,morphology by polarizing optical microscopy and small angle X-ray *** on the experimental results obtained the macromolecular condensed state of the nascent UHPE powder is a rare case of a multi-chain condensed state of non-interpenetrating chains,involving interlaced extended chain crystalline layers and relaxed parallel chain amorphous *** melting,a nematic rubbery state of nanometer size domain *** nematic-isotropic transition temperature was judged from literature data to be at least 220 degreesC,possibly higher than 300 ℃,the exact temperature is however not sue because of chain degradation at such high *** recrystallization process from the melt is a crystallization from a nematic rubbery *** drop of remelting peak temperature by 10 K of the specimen recrystallized from its melt as compared to the nascent state has its origin in the decrease both of the crystalline chain stem length and of the degree of *** remelting peak temperature could be returned close to that of the nascent state by annealing at 120~130 ℃.

关键词： ultra high molar mass polyethylene recrystallization remelting annealing nematic state

Winter-spring minimum temperature variations inferred from tree-ring δ^(13)C in southeastern China

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Journal of Forestry Research 2024年第5期35卷 182-190页

作者： Wenli li Feifei Zhou heng Zhang Keyan Fang Key Laboratory of Humid Subtropical Eco-Geographical Process(MOE) College of Geographic SciencesFujian Normal UniversityFuzhou 350007People’s Republic of China

Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current ***,tem-perature reconstructions in humid southeastern China are scarce and particularly lack long-term data,limiting us to obtain a complete picture of regional temperature *** this study,we present a well-verified reconstruction of winter-spring(January–April)minimum temperatures over southeastern China based on stable carbon isotopic(δ^(13)C)records of tree rings from Taxus wallichiana *** from 1860 to *** reconstruction accounted for 56.4%of the total observed *** periods occurred during the 1860s–1910s and 1960s–*** temperatures have had an upward trend since the 1920s,most of the cold extremes were in recent *** El Niño-Southern Oscillation(ENSO)variance acted as a key modulator of regional winter-spring minimum temperature ***,teleconnections between them were a nonlinear process,i.e.,a reduced or enhanced ENSO variance may result in a weakened or intensified temperature-ENSO relationship.

关键词： Tree rings Carbon isotope Southeastern China Extreme coldness El nino-southern oscillation

Monogamy and polygamy for the generalized W-class states using unified-(q,s)entropy

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 10-22页

作者： Bo li Bing Xie Zhanjun Zhang heng Fan School of Computer and Computing Science Hangzhou City UniversityHangzhou 310015China Department of Mathematics East China University of TechnologyNanchang 330013China School of Information&Electronic Engineering(Sussex Artificial Intelligence Institute) Zhejiang Gongshang UniversityHangzhou 310018China Institute of Physics Chinese Academy of SciencesBeijing 100190China

We describe the entanglement distribution and restricted shareability of the multipartite generalized W-class states and their reduced density matrix under arbitrary partitions by using monogamy and polygamy relation based on the unified-(q,s)***,we provide an analytical formula of unified-(q,s)entanglement(UE)and an analytical lower bound of unified-(q,s)entanglement of assistance(UEo A)for a reduced density matrix of a generalized W-class ***,we use these two analytical formulas to derive the monogamy and polygamy inequalities for a reduced density matrix of a qudit generalized W-class(GW)*** establish two partition-dependent residual entanglements based on the new monogamy relation,which is helpful to obtain a comprehensive analysis of entanglement dynamics of generalized W-class ***,we investigate tighter monogamy and polygamy relations based on the power ofαth(α≥0)for UE andβth(β≥0)for UEo A,*** results show that the entanglement distribution characteristics of generalized W-class states satisfying stronger constraints can be described more accurately.

关键词： monogamy polygamy multiqudit unified entropy