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Ring-opening Copolymerization of ε-Caprolactone and δ-Valerolactone Catalyzed by a 2,6-Bis(amino)phenol Zinc Complex

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Chinese Journal of Polymer Science 2020年第3期38卷 240-247,I0006页

作者： Qian Hu su-yun jie Pierre Braunstein Bo-Geng Li State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Universitéde Strasbourg CNRSCHIMIE UMR 7177Laboratoire de Chimie de Coordination67081 Strasbourg CedexFrance

In combination with methyllithium,a 2,6-bis(amino)phenol zinc complex 1 was used in the ring-opening polymerization ofδ-valerolactone in the absence or presence of benzyl alcohol and showed high efficiency,mainly producing cyclic and linear polyvalerolactones,*** the basis of homopolymerization,the ring-opening copolymerization ofε-caprolactone andδ-valerolactone was *** P(CL-co-VL)random copolymers,PCL-b-PVL and PVL-b-PCL diblock copolymers,were prepared by varying the feeding strategy(premixing or sequential feeding).The copolymer composition was adjusted by varying the feeding ratio of two *** structure and thermal properties of obtained polymers were characterized by GPC,1 H-NMR,13 C-NMR,MALDI-TOF mass spectroscopy,and DSC,respectively.

关键词： Zn complex Copolymerization Block copolymer Random copolymer

A real-world study of the differences in Traditional Chinese Medicine diagnosis and treatment rules for coronavirus disease 2019 between Northern and Southern China

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Journal of Traditional Chinese Medicine 2024年第4期44卷 822-829页

作者： su Rui su Youzhu WANG Shuo FAN jie LIU Qingquan LIU Mifeng Department of infectious diseases Capital Medical University Beijing Hospital of Traditional Chinese Medicine

OBJECTIVE: To explore the differences in Traditional Chinese Medicine(TCM) diagnosis and treatment rules for coronavirus disease 2019(COVID-19) between Northern and Southern China based on the real-world data from 982 COVID-19 patients. METHODS: All consecutive cases of COVID-19 admitted to the TCM department of designated COVID-19 hospitals in eight provinces and cities were retrospectively analyzed. Patients were divided into a Northern and a Southern group according to the location of the admitting hospital. The symptoms, syndrome elements, syndrome distribution and herbal treatments were analyzed. The core prescriptions were extracted using the multiscale backbone-based network comparison algorithm(msbNC). REsuLTS: The distribution of syndrome elements showed that dampness was common in Northern and Southern China, wind and heat were more often present in the South, while fire toxin and spleen deficiency were more often encountered in the North. The distribution of syndromes showed that the South was dominated by heat dampness accumulating in the lung(55.69%), while the North was dominated by dampness-toxin stagnating in the lung(44.90%).The results of core prescription mining showed that dispelling dampness, dispersing wind, clearing heat and strengthening spleen were the common treatment methods in Northern and Southern China. For mild cases, Jinyinhua(Flos Lonicerae) and Lianqiao(Fructus Forsythiae suspensae) were often used in the South to clear heat and relieve exterior symptoms, while Chaihu(Radix Bupleuri Chinensis) and Huangqin(Radix Scutellariae Baicalensis) were often used in the North to relieve muscles by expelling heat. For moderate cases, Chaihu(Radix Bupleuri Chinensis), Qinghao(Herba Artemisiae Annuae), and Shigao(Gypsum Fibrosum) were often used to clear heat of Tri-jiao Channel and stomach in the South, while Fuling(Poria), Chenpi(Pericarpium Citri Reticulatae), and Dangshen(Radix Codonopsis) were often used to invigorate spleen and remove damp

关键词： COVID-19 North-South difference core prescription medicine, Chinese traditional retrospective studies syndrome

Enhanced memristor performance via coupling effect of oxygen vacancy and ferroelectric polarization

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Journal of Materials Science & Technology 2024年第4期171卷 139-146页

作者： Zhi yun Yue Zhi Dong Zhang Zhan jie Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

As a new type of nonvolatile memory,the resistive memristor has broad application prospects in in-formation storage and neural computing based on its excellent resistive switching(RS)*** present,it is still a great challenge to improve both ferroelectric polarization and leakage current to achieve a high RS on/offratio of ferroelectric ***,epitaxial Pb(Zr_(0.40)Ti_(0.60))O_(3)(PZT)thin films with low content Ca doping were deposited on the Nb:SrTiO_(3)substrate to prepare PCZT/NSTO het-erostructures and their RS behaviors were *** research findings show that compared with pure PZT film,the ferroelectric polarization of 1-mol%-Ca-doped PZT film is slightly improved,while the leak-age current is increased by three orders of ***,the RS on/offratio reaches 2.5×10^(5),about three orders of magnitude higher than pure PZT *** theoretical analysis reveals that the RS behavior of PCZT/NSTO heterostructures is controlled by the PCZT/NSTO interfacial barrier and the space charge-limited current *** results demonstrate that the ferroelectricity and electricity of ferroelectric thin films can be improved simultaneously by doping low-content Ca ions to increase the RS performance,which provides a good reference for the development of high-performance ferroelectric memristor devices.

关键词： Ferroelectric memristor Ca-doped PZT Ferroelectric polarization Oxygen vacancies Resistive switching

Transcriptomic and machine learning analyses identify hub genes of metabolism and host immune response that are associated with the progression of breast capsular contracture

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Genes & Diseases 2024年第3期11卷 427-437页

作者： Yukun Mao Xueying Hou su Fu jie Luan Breast Plastic and Reconstructive surgery Center Plastic Surgery HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100144China

Capsular contracture is a prevalent and severe complication that affects the post-operative outcomes of patients who receive silicone breast *** present,prosthesis replacement is the major treatment for capsular contracture after both breast augmentation procedures and breast reconstruction following breast cancer ***,the mecha-nism(s)underlying breast capsular contracture remains *** study aimed to identify the biological features of breast capsular contracture and reveal the potential underlying mechanism using RNA *** tissues from 12 female patients(15 breast capsules)were divided into low capsular contracture(LCC)and high capsular contracture(HCC)groups based on the Baker ***,41 lipid metabolism-related genes were identified through enrichment analysis,and three of these genes were identified as candidate genes by SVM-RFE and LASSO *** then compared the proportions of the 22 types of im-mune cells between the LCC and HCC groups using a CIBERSORT analysis and explored the Cor-relation between the candidate hub features and immune ***,PRKAR2B was positively correlated with the differentially clustered immune cells,which were M1 macro-phages and follicular helper T cells(area under the ROC=0.786).In addition,the expression of PRKAR2B at the mRNA or protein level was lower in the HCC group than in the LCC *** molecular mechanisms were identified based on the expression levels in the high and low PRKAR2B *** findings indicate that PRKAR2B is a novel diagnostic biomarker for breast capsular contracture and might also influence the grade and progression of capsularcontracture.

关键词： Biomarker Breastcapsular contracture Immune infiltration Machinelearning algorithms PRKAR2B

Engineering particles towards 3D supraballs-based passive cooling via grafting CDs onto colloidal photonic crystals

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Chinese Chemical Letters 2024年第4期35卷 457-463页

作者： jie Wu Xiaoqing Yu Guoxing Li su Chen State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

Particle engineering has opened the floodgates to material science in both fundamental and application field. However, covalent interactions have not yet been adequately designed in the particle engineering for functional colloidal photonic crystals(CPCs). Herein, we achieved covalent coupling between carboxylrich poly(styrene-acrylic acid)(P(St-AA)) monodispersed colloidal particles and amine-rich carbon dots(CDs) based on an feasible and universal particle engineering strategy. The designed CDs-grafted P(St-AA)monodispersed colloidal particles initiate a hydrogen bond-driven assembly mode and ensure the construction of large-scale crack-free CPCs. Moreover, the CDs equipped with selective broad-band absorption capacity could improve the saturation of structural colors for high-visibility CPCs. Furthermore, an injectable photonic hydrogel(IPH) is developed to design CPC supraball hydrogel via integrating the CDsgrafted P(St-AA) CPC supraballs with supramolecular hydrogel. Combining superior flexibility, sufficient self-healing capacity of supramolecular hydrogel with visual optical information of our CPC supraballs, a cyclically reversible coding and decoding system was developed. Meanwhile, we firstly demonstrated the novel strategy of 3D supraballs-based passive cooling. The designed 3D CPC supraball hydrogel presents nearly full observation angle reflections behavior and excellent water evaporation capacity and achieves3.6 ℃ temperature drops, showing the application advantages in 3D thermal management. This work not only provides a new insight for manipulating optical properties of CPCs, but also demonstrates an easyto-perform platform, as well as indicates the direction for the promising application of CPCs.

关键词： Particle engineering Carbon dots Colloidal photonic crystals Passive cooling Digital coding

Rebuilding the theory of isotope fractionation for evaporation of silicate melts under vacuum condition

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Acta Geochimica 2024年第4期43卷 661-676页

作者： jie Wang yun Liu Research Center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Isotope eff ects are pivotal in understanding silicate melt evaporation and planetary accretion *** on the Hertz-Knudsen equation,the current theory often fails to predict observed isotope fractionations of laboratory experiments due to its oversimplified ***,we point out that the Hertz-Knudsen-equation-based theory is incomplete for silicate melt evaporation cases and can only be used for situations where the vaporized species is identical to the one in the *** propose a new model designed for silicate melt evaporation under *** model considers multiple steps including mass transfer,chemical reaction,and *** derivations reveal a kinetic isotopic fractionation factor(KIFF orα)αour model=[m(^(1)species)/m(^(2)species)]^(0.5),where m(species)is the mass of the reactant of reaction/nucleation-limiting step or species of diffusion-limiting step and superscript 1 and 2 represent light and heavy isotopes,*** model can eff ectively reproduce most reported KIFFs of laboratory experiments for various elements,i.e.,Mg,Si,K,Rb,Fe,Ca,and ***,the KIFF-mixing model referring that an overall rate of evaporation can be determined by two steps jointly can account for the eff ects of low P_(H2)pressure,composition,and *** addition,we find that chemical reactions,diffusion,and nucleation can control the overall rate of evaporation of silicate melts by using the fitting slope in ln(−ln f)versus ln(t).Notably,our model allows for the theoretical calculations of parameters like activation energy(E_(a)),providing a novel approach to studying compositional and environmental eff ects on evaporation processes,and shedding light on the formation and evolution of the proto-solar and Earth-Moon systems.

关键词： Evaporation Kinetic isotopic fractionation Chemical kinetics Hertz-Knudsen equation CAIS

An overview on the distributed internal model approach and its applications

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Control Theory and Technology 2024年第3期22卷 345-359页

作者： Youfeng su He Cai jie Huang College of Computer and Data Science Fuzhou UniversityFuzhou 350116China School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641China Department of Mechanical and Automation Engineering The Chinese University of Hong KongShatinHong KongChina

The cooperative output regulation problem has been studied by two approaches:the distributed observer(DO)approach and the distributed internal model(DIM)approach,*** of these two approaches has its own merits and ***,we presented an overview on the cooperative output regulation problem by the DO *** paper further surveys the cooperative output regulation problem by the DIM *** first summarize the constructions and the roles of two different versions of the internal models:the distributed p-copy internal model and the distributed canonical internal ***,we describe an integrated framework that combines the DO approach and the DIM *** and variants of the DIM and their applications will also be highlighted.

关键词： Cooperative output regulation Distributed p-copy internal model Distributed canonical internal model Integrated approach

Ultrafast Molecular Movies:Probing Chemical Dynamics with Femtosecond Electron and X-Ray Diffraction

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CCS Chemistry 2024年第5期6卷 1092-1109页

作者： Qianci Wang Longteng yun jie Yang Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084

Understanding the process of chemical reactions has always been a relentless pursuit for *** development of femtosecond pump-probe techniques since the 1980s has revolutionized the field of chemical dynamics,enabling the capture of timeresolved snapshots of reactions on the femtosecond *** from the 2010s,breakthroughs in femtosecond electron and X-ray sources has enabled ultrafast electron and X-ray diffraction techniques,which is able to directly reveal the temporal evolution of atomic geometries of molecules,allowing for the creation of molecular ***-phase molecular movies reveal intrinsic intramolecular processes,while liquid-phase molecular movies provide insights for complicated solvent-solute *** minireview focuses on the advances in studying gasphase and liquid-phase molecular dynamics(MD)using ultrafast electron and X-ray diffraction techniques on femtosecond and picosecond *** fast-developing experimental capability of the direct observation of molecular structural evolution during chemical reactions,on its natural femtosecond timescale and subangstrom length scale,offers tremendous potential for the field of chemical kinetics and MD.

关键词： molecular movie electron diffraction X-raydiffraction femtosecond gasphase liquidphase

METTL3 regulates glucose transporter expression in placenta exposed to hyperglycemia through the mTOR signaling pathway

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Chinese Medical Journal 2024年第13期137卷 1563-1575页

作者： jie Ning Jing Huai Shuxian Wang jie Yan Rina su Muqiu Zhang Mengtong Liu Huixia Yang Department of Obstetrics and Gynaecology Peking University First HospitalBeijing 100034China Beijing Key Laboratory of Maternal Foetal Medicine of Gestational Diabetes Mellitus Beijing 100034China Peking University Beijing 100034China

Background:Alterations in the placental expression of glucose transporters(GLUTs),the crucial maternal-fetal nutrient transporters,have been found in women with hyperglycemia in pregnancy(HIP).However,there is still uncertainty about the underlying effect of the high-glucose environment on placental GLUTs expression in ***:We quantitatively evaluated the activity of mammalian target of rapamycin(mTOR)and expression of GLUTs(GLUT1,GLUT3,and GLUT4)in the placenta of women with normal pregnancies(CTRL,n=12)and pregnant women complicated with poorly controlled type 2 diabetes mellitus(T2DM,n=12)by *** addition,BeWo cells were treated with different glucose concentrations to verify the regulation of ***,changes in the expression of GLUTs following the activation or suppression of the mTOR pathway were also assessed using MHY1485/rapamycin(RAPA)treatment or small interfering RNA(siRNA)-mediated silencing ***,we further explored the alteration and potential upstream regulatory role of methyltransferase-like 3(METTL3)when exposed to ***:mTOR,phosphorylated mTOR(p-mTOR),and GLUT1 protein levels were upregulated in the placenta of women with T2DM compared with those *** BeWo cells,mTOR activity increased with increasing glucose concentration,and the expression of GLUT1,GLUT3,and GLUT4 as well as GLUT1 cell membrane translocation were upregulated by hyperglycemia to varying *** the drug-mediated and genetic depletion of mTOR signaling in BeWo cells suppressed GLUTs expression,whereas MHY1485-induced mTOR activation upregulated GLUTs ***,high glucose levels upregulated METTL3 expression and nuclear translocation,and decreasing METTL3 levels suppressed GLUTs expression and mTOR activity and vice ***,in METTL3 knockdown BeWo cells,the inhibitory effect on GLUTs expression was eliminated by activating the mTOR signaling pathway using ***:High-g

关键词： Glucose transporters Hyperglycemia Type 2 diabetes mellitus Pregnancy Mammalian target of rapamycin Methyltransferase-like 3