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Earth and Planetary Physics 2024年第2期8卷 368-374页

作者： LuHuai Jiao Xin ma YuanNong Zhang TaiFeng Jin Song Fu BinBin ni Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation *** measurements have indicated that the commonly used maxwellian and Kappa distributions are inadequate for capturing the realistic spectral distributions of radiation belt *** we adopt the Kappa-type(KT)distribution as the fitting function and perform a statistical analysis to investigate the radiation belt electron flux spectra observed by the Van Allen *** calculating the optimal values of the key KT distribution parameters(i.e.,κandθ2)from the observed spectral shapes,we fit the radiation belt electron fluxes at different L-shells under different geomagnetic *** this manner,we obtain typical values of the KT distribution parameters,which are statistically feasible for modeling the radiation belt electron flux profiles during either geomagnetically quiet or active periods.A comparison of the KT distribution model results with those using the maxwellian or Kappa distribution reveals the advantage of the KT distribution for studying the overall properties of the radiation belt electron spectral distribution,which has important implications for deepening the current understanding of the radiation belt electron dynamics under evolving geomagnetic conditions.

关键词： radiation belt electron Kappa-type distribution fitting geomagnetic storm

Recent progress in MnBi2nTe3n+1 intrinsic magnetic topological insulators: crystal growth, magnetism and chemical disorder

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National Science Review 2024年第2期11卷 65-80页

作者： Chaowei Hu Tiema Qian ni ni Department of Physics and Astronomy and California Nano Systems Institute University of California-Los Angeles

The search for magnetic topological materials has been at the forefront of condensed matter research for their potential to host exotic states such as axion insulators, magnetic Weyl semimetals, Chern insulators,etc. To date, the MnBi2nTe3n+1family is the only group of materials showcasing van der Waals-layered structures, intrinsic magnetism and non-trivial band topology without trivial bands at the Fermi level. The interplay between magnetism and band topology in this family has led to the proposal of various topological phenomena, including the quantum anomalous Hall effect, quantum spin Hall effect and quantum magnetoelectric effect. Among these, the quantum anomalous Hall effect has been experimentally observed at record-high temperatures, highlighting the unprecedented potential of this family of materials in fundamental science and technological innovation. In this paper, we provide a comprehensive review of the research progress in this intrinsic magnetic topological insulator family, with a focus on single-crystal growth, characterization of chemical disorder, manipulation of magnetism through chemical substitution and external pressure, and important questions that remain to be conclusively answered.

关键词： MnBi2Te4 magnetic topological insulator magnetism tuning antiferromagnetism ferromagnetism pressure chemical doping

Inhibiting HMGCR represses stemness and metastasis of hepatocellular carcinoma via Hedgehog signaling

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Genes & Diseases 2024年第5期11卷 470-483页

作者： Zhirong Zhang Jiayao Yang Rui Liu Jing ma Kai Wang Xiaojun Wang ni Tang Key Laboratory of Molecular Biology for Infectious Diseases(Ministry of Education) Institute for Viral HepatitisDepartment of Infectious DiseasesThe Second Affiliated HospitalChongqing Medical UniversityChongqing 400016China Institute of Hepatobiliary Surgery Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China

Cancer stem cells(CSCs)play a crucial role in tumor initiation,recurrence,metastasis,and drug ***,the current understanding of CSCs in hepatocellular carcinoma(HCC)remains *** a comprehensive analysis of the database,it has been observed that 3-hydroxy-3-methylglutaryl-coenzyme A reductase(HMGCR),a critical enzyme involved in cholesterol synthesis,is up-regulated in HCC tissues and liver ***,high expression of HMGCR is associated with a poor prognosis in patients with ***,HMGCR promotes the stemness and metastasis of HCC both in vitro and in *** screening various signaling pathway inhibitors,we have determined that HMGCR regulates stemness and metastasis by activating the Hedgehog signaling in ***,HMGCR positively correlates with the expression of the Smoothened receptor and facilitates the nuclear translocation of the transcriptional activator GLI family zinc finger *** of the Hedgehog pathway can reverse the stimulatory effects of HMGCR on stemness and metastasis in ***,simvastatin,an FDA-approved cholesterol-lowering drug,has been shown to inhibit stemness and metastasis of HCC by targeting *** together,our findings suggest that HMGCR promotes the regeneration and metastasis of HCC through the activation of Hedgehog signaling,and simvastatin holds the potential for clinical suppression of HCC metastasis.

关键词： Cancer stem cells Hedgehog Hepatocellular carcinoma Metastasis Statin

Probing the endoplasmic reticulummitochondria interaction in Alzheimer's disease:searching far and wide

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Neural Regeneration Research 2024年第10期19卷 2103-2104页

作者： giulia Dematteis Laura Tapella Dmitry Lim Department of Pharmaceutical Sciences Universitàdel Piemonte Orientale“Amedeo Avogadro”NovaraItaly

Alzheimer's disease(AD)is the most frequent,form of dementia in elderly people and is an incurable disease with an exponentially growing number of *** deposition of amyloid-β(Aβ)plaques and intraneuronal formation o... 详细信息

关键词： Alzheimer Aβ reticulum

Regional features of pollen R-values in China

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Science China Earth Sciences 2024年第1期67卷 295-308页

作者： Jie XIA Jian ni College of Life Sciences Zhejiang Normal UniversityJinhua 321004China Jinhua Mountain observation and Research Station for Subtropical Forest Ecosystems Jinhua 321004China

Establishing a quantitative relationship between modern pollen and vegetation remains a pivotal but intricate pursuit within the field of Quaternary *** R-value,a well-established and traditional metric characterized by its simplicity and direct applicability,serves to calibrate the nonlinear disparities between surface pollen and modern *** study entails the construction of a comprehensive pollen R-value dataset for China derived from R-values published between 1987 and *** dataset,compiled after rigorous screening,calibration,and standardization processes,encompasses 898 modern pollen sampling sites and 2115 pollen R-value data entries,encapsulating 152 pollen taxa spanning 65 families and 113 *** the extracted R-values yielded the following insights:(1)A macrospatial analysis validates previously established knowledge at a site-specific ***,pollen R-value variations across China are statistically *** two-thirds of pollen taxa exhibit underrepresentation(e.g.,Taxodiaceae,Corylus,nitraria,Tamarix,Cyperaceae,Poaceae,and Fabaceae),while the remaining one-third display overrepresentation(e.g.,Pinus,Picea,Betula,Ephedra,Chenopodiaceae,and Artemisia).The degree of underrepresentation surpasses that of overrepresentation,and the representation patterns of Castanea,Quercus,Polygonaceae,and Asteraceae are contingent upon vegetation types.(2)Pollen R-values follow distinct spatial distribution patterns within *** the woody vegetation region of eastern China,R-values progressively decline from north to south,correlating with rising temperatures and ***,in herbaceous vegetation regions of northern and western China,R-values decrease from east to west and from northeast to southwest,corresponding to increased ***,pollen R-values manifest variation contingent on pollen taxa,vegetation types,and climatic regions,even differing for the same taxa across varying

关键词： Pollen R-value Modern pollen-vegetation relationship Regional pattern Variability Paleovegetation reconstruction

Women health and microbiota:Different aspects of well-being

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World Journal of Gastroenterology 2024年第10期30卷 1287-1290页

作者： giulia Nannini Amedeo Amedei Department of Experimental and Clinical Medicine University of FlorenceFlorence 50134Italy Network of Immunity in Infection Malignancy and Autoimmunity(NIIMA)Universal Scientific Education and Research Network(USERN)Florence 50134Italy

In this editorial,we comment on the article by marano et al recently published in the World Journal of Gastroenterology 2023;29(45):*** focus on the role of gut microbiota(GM)in women’s health,highlighting the need to thoroughly comprehend the sex differences in ***,the host and GM support the host’s *** microbiota components consist of viruses,bacteria,fungi,and *** complex is an essential part of the host and is involved in neu-rological development,metabolic control,immune system dynamics,and host dynamic *** has been shown that differences in the GM of males and females can contribute to chronic diseases,such as gastrointestinal,metabolic,neurological,cardiovascular,and respiratory *** differences can also result in some sex-specific changes in *** day,research on GM reveals new and more expansive frontiers,offering a wealth of innovative oppor-tunities for preventive and precision medicine.

关键词： Gut microbiota Women Immune system Well-being Hormones Sexdifferences

Theoretical optimization of micropillar arrays for structurally stable bioinspired dry adhesives

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 124-129页

作者： Ke ni Zhengzhi Wang Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518108China

Inspired by the excellent adhesion performances of setae structure from organisms,micro/nano-pillar array has become one of the paradigms for adhesive *** micropillar arrays are composed of the resin pillars for adhesion and the substrate with different elastic modulus for *** stress singularity at the bi-material corner between the pillars and the substrate can induce the failure of the micropillar-substrate corner and further hinder the fabrication and application of micropillar arrays,yet the design for the stability of the micropillar array lacks systematical and quantitative *** this work,we develop a semi-analytical method to provide the full expressions for the stress distribution within the bi-material corner combining analytical derivations and numerical *** predictions for the stress within the singularity field can be obtained based on the full expressions of the *** good agreement between the predictions and the FEM results demonstrates the high reliability of our *** adopting the strain energy density factor approach,the stability of the pillar-substrate corner is assessed by predicting the failure at the *** the elastic mismatch between the pillar and substrate given in this paper,the stability can be improved by increasing the ratio of the shear modulus of the substrate to that of the *** study provides accurate predictions for the stress distribution at the bi-material corner and can guide the optimization of material combinations of the pillars and the substrate for more stable bioinspired dry adhesives.

关键词： Micropillar array Stability Bi-material corner Dry adhesive

Asymmetric side-chain engineering of organic semiconductor for ultrasensitive gas sensing

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Chinese Chemical Letters 2024年第3期35卷 428-433页

作者： Xiaoying ma Xiaojuan Dai Lanyi Xiang Jiajun Chang Danfeng Zhi Haozhen Zhao Zhenjie ni Ye Zou Xike Gao Fengjiao Zhang School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Laboratory of organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Synthetic and Self-Assembly Chemistry for organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Binzhou Institute of Technology Binzhou 256606China

Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical *** alkyl chains are fundamental units in tailering the solubility and assemblability,among which the asymmetric properties have been reported as key element for controlling the packing motifs and intrinsic charge ***,we expanded the scope of molecular asymmetry dependent sensing features based on a new series of naphthalene diimides(NDI)-based derivatives substituted with a same branching alkyl chain but various linear-shaped alkyl chains(Cn-).A clear molecular stacking change,from head-to-head bilayer to head-to-tail monolayer packing model,is observed based on the features of anisotropic molecular interactions with the change in the chain *** importantly,a unique LUMo level shift of 0.17 eV is validated for NDI-PhC4,providing a record sensitivity up to 150%to 0.01 ppb ammonia,due to the desired molecular reactivity and device amplification *** results indicate that asymmetric side-chain engineering opens a route for breath healthcare.

关键词： organic thin film transistor Asymmetric side chain Gas sensing Molecular stacking Energy level manipulating

oligomerization of drug transporters:Forms,functions,and mechanisms

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Acta Pharmaceutica Sinica B 2024年第5期14卷 1924-1938页

作者： Chunxu ni Mei Hong College of Life Sciences South China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural organisms South China Agricultural UniversityGuangzhou 510642China

Drug transporters are essential players in the transmembrane transport of a wide variety of clinical *** broad substrate spectra and versatile distribution pattern of these membrane proteins infer their pharmacological and clinical *** our accumulating knowledge on the three-dimensional structure of drug transporters,their oligomerization status has become a topic of intense study due to the possible functional roles carried out by such kind of post-translational modification(PTM).In-depth studies of oligomeric complexes formed among drug transporters as well as their interactions with other regulatory proteins can help us better understand the regulatory mechanisms of these membrane proteins,provide clues for the development of novel drugs,and improve the therapeutic *** this review,we describe different oligomerization forms as well as their structural basis of major drug transporters in the ATP-binding cassette and solute carrier superfamilies,summarize our current knowledge on the influence of oligomerization for protein expression level and transport function of these membrane proteins,and discuss the regulatory mechanisms of ***,we highlight the challenges associated with the current oligomerization studies and propose some thoughts on the pharmaceutical application of this important drug transporter PTM.

关键词： Drug development Drug transporters oligomerization Protein expression Protein–protein interaction Regulatory mechanism Structural basis Transport function

Modern phenomics to empower holistic crop science, agronomy, and breeding research

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Journal of Genetics and Genomics 2024年第8期51卷 790-800页

作者： ni Jiang Xin-Guang Zhu Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China Center of Excellence for Molecular Plant Sciences Chinese Academy of SciencesShanghai 200032China

Crop phenomics enables the collection of diverse plant traits for a large number of samples along different time scales,representing a greater data collection throughput compared with traditional *** modern crop phenomics use different sensors to collect reflective,emitted,and fluorescence signals,etc.,from plant organs at different spatial and temporal *** multi-modal,high-dimensional data not only accelerates basic research on crop physiology,genetics,and whole plant systems modeling,but also supports the optimization of field agronomic practices,internal environments of plant factories,and ultimately crop *** challenges and opportunities facing the current crop phenomics research community include developing community consensus or standards for data collection,management,sharing,and processing,developing capabilities to measure physiological parameters,and enabling farmers and breeders to effectively use phenomics in the field to directly support agricultural production.

关键词： Crop phenomics High-throughput phenotyping Traits Crop designer breeding Agronomy