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Response mechanism of soil microorganisms to simulated precipitation in the source wetland of Qinghai Lake

Ecological Processes 2024年第2期13卷 61-71页

作者： Xinye wa.g ni Zhang Kelong Chen Tiexi Chen Desheng Qi Yuanxi ma School of geographical Sciences Qinghai Normal University National Positioning Observation and Research Station of Qinghai Lake Wetland Ecosystem in Qinghai National Forestry and Grassland Administration Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal University School of geographical Sciences Nanjing University of Information Science and Technology Qinghai Provincial land spatial Planning Research Institute

Background Changes in precipitation patterns crucially impact soil microbial communities, and the ecosystem in Qinghai-Tibet Plateau(QTP) is highly vulnerable to climate change. However, we do not fully understand how soil microbial communities in the source wetlands of QTP respond to changes in precipitation. In this study, we employed advanced techniques such as high-throughput sequencing and metabolomics to investigate how soil microbial communities in a source wetland of Qinghai Lake respond to changes in precipitation after quadrennial precipitation *** Our findings showed that the predominant microbiota in the source wetland was Proteobacteria. Interestingly, alterations in precipitation levels, whether increased or reduced, did not significantly impact the diversity or functional groups of the microbial community. However, the structure of the microbial community did respond notably to changes in precipitation, leading to shifts in the relative abundance of Spirochaetes and Treponema. A notable finding was that reduced precipitation levels(– 25% and-50%) and mild increases in precipitation(25%) within the region contributed to increased soil carbon content. However, this effect ceased to manifest when precipitation increased by 50%. Additionally, the reduction in precipitation prompted the release of soil metabolites like syringic acid and aldosterone, while enhanced precipitation resulted in a decrease in aldosterone *** Precipitation changes altered the relative abundance of soil microbial communities and metabolites, which was conducive to increasing carbon storage in this alpine wetland.

关键词： Qinghai-Tibet Plateau Climate change Precipitation gradient Carbon and nitrogen cycles LC/MS

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A statistical analysis of the Kappa-type energy spectrum distribution of radiation belt electrons observed by Van Allen Probes

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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

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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

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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 wa.g Xiaojun wa.g 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

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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 rema.ning 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

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Inter-annual variations of dissolved oxygen and hypoxia off the northern Changjiang River(Yangtze River) Estuary in summer from 1997 to 2014

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Acta Oceanologica Sinica 2024年第6期43卷 119-130页

作者： Anqi Liu Feng Zhou Xiao ma Qiang Zhao guanghong Liao Yuntao Zhou Di Tian Xiaobo ni Ruibin Ding College of Oceanography Hohai UniversityNanjing 210098China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Observation and Research Station of Changjiang River Delta marine Ecosystems Ministry of Natural ResourcesZhoushan 316022China ningbo marine Center Ministry of Natural ResourcesNingbo 315000China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China Institute of Polar and Ocean Technology Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

Hypoxia off the Changjiang River Estuary has been the subject of much attention,yet systematic observations have been lacking,resulting in a lack of knowledge regarding its long-term change and *** revisiting the repeated surveys of dissolved oxygen(DO) and other relevant hydrographic parameters along the section from the Changjiang River Estuary to the Jeju-do in the summer from 1997 to 2014,rather different trends were revealed for the dual low-DO *** nearshore low-DO core,located close to the river mouth and relatively stable,shows that hypoxia has become more severe with the lowest DO descen ding at a rate of -0.07 mg/(L·a) and the thickness of low-DO zone rising at a rate of 0.43 m/*** offshore core,centered around 40-m isobath but moving back and forth between 123.5°-125°E,shows large fluctuations in the minimum DO concentration,with the thickness of low-DO zone falling at a rate of -1.55 m/*** probable factors affecting the minimum DO concentration in the two regions also *** the nearshore region,the decreasing minimum DO is driven by the increase in both stratification and primary productivity,with the enhanced extension of the Changjiang River Diluted water(CDW) strengthening *** the offshore region,the fluctuating trend of the minimum DO concentration indicates that both DO loss and DO supplement are *** DO loss is primarily attributed to bottom apparent oxygen utilization caused by the organic matter decay and is also relevant to the advection of low-DO water from the nearshore *** DO supplement is primarily due to weakened *** analysis also shows that the minimum DO concentration in the nearshore region was extremely low in 1998,2003,2007 and 2010,related to El ni?o signal in these summers.

关键词： dissolved oxygen low-DO Changjiang River Estuary interannual variations dual-core

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Dynamics of iron and aluminum storages in a subtropical forest headwater stream

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Journal of Mountain Science 2024年第7期21卷 2193-2205页

作者： YI Qiumeng ma Diting PENg Yan ZHAO Zemin YUAN Chaoxiang YUAN Ji ni Xiangyin WU Fuzhong YUE Kai AN Nannan Key Laboratory of Humid Subtropical Eco-geographical Processes of Ministry of Education School of Geographical SciencesFujian Normal UniversityFuzhou 350117China Fujian Sanming Forest Ecosystem National Observation and Research Station Sanming 365002China

The forest headwater streams are important hubs for connecting terrestrial and aquatic ecosystems,with plant litter and sediments as the major carriers for material migrations;however,until now we knew little about the dynamics of trace elements such as iron(Fe)and aluminum(Al)in forest headwater ***,we quantitatively identified the spatiotemporal dynamics of Fe and Al storages in plant litter and sediments and their influencing factors in a subtropical forest headwater stream,and assessed the potential pollution *** results showed that:(1)the mean concentrations of Fe and Al in plant litter(sediments)were 5.48 and 8.46(7.39 and 47.47)g·kg^(-1),and the mean storages of Fe and Al in plant litter(sediments)were 0.26 and 0.43(749.04 and 5030.90)g·m^(-2),respectively;(2)the storages of Fe and Al in plant litter and sediments significantly fluctuated from January to December,and showed a decreasing pattern from the source to mouth;and(3)storages of Fe and Al had no significant correlation with riparian forest type and the present of tributary and the Fe and Al storages in plant litter were mainly affected by water temperature and water alkalinity,and their storages in sediments were mainly affected by water temperature and frequency of rainfall;and(4)there were no anthropogenic pollution in Fe and Al in the forest headwater *** study revealed the primary factors of concentrations and storages of Fe and Al in plant litter and sediments in a forest headwater stream,which will improve our understanding of the role of headwater streams in forest nutrient storage and cycling along with hydrological processes.

关键词： Plant litter Sediments Storage Forest headwater stream Stream characteristics Trace element

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Dioscin from Polygonatum sibiricum induces apoptosis and autophagy in Ishikawa human endometrial cancer cell and in vivo

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Food Science and Human Wellness 2024年第5期13卷 2601-2616页

作者： Xiaoli Li Runhui ma Zhijing ni Wei wa.g Kiran Thakur Jianguo Zhang Zhaojun Wei School of Biological Science and Engineering North Minzu UniversityYinchuan 750021China School of Food and Biological Engineering Hefei University of TechnologyHefei 230009China School of Public Health Anhui University of Science and TechnologyHuainan 232001China

With an aim to comprehend the precise regulatory mechanism of dioscin against endometrial carcinoma(EC), we firstly extracted the components from Polygonatum sibiricum followed by identification and structural characterization. The anti-EC activity of dioscin was initially determined based on the inhibition of Ishikawa cell proliferation and tumor growth. The high-throughput sequencing data indicated that dioscin not only promoted apoptosis, including decrease of poly ADP-ribose polymerase(PARP) and B-cell lymphoma-2(Bcl-2) and increase of c-PARP and Bcl-2-associcated agonist of cell death(Bad), but also induced autophagy, including increase of autophagic lysosomes and LC3Ⅱ/LC3Ⅰ ratio. Mechanistic exploration suggested that dioscin induced autophagy and apoptosis through inhibition of PI3K/AKT/mTOR signaling pathway. Besides, the dioscin-regulated p53 pathway was mainly involved in autophagy induction. Furthermore, inhibition of Ishikawa cell autophagy was linked to dioscin-induced apoptosis. Our data suggest the immense potential of dioscin for the development of functional food for EC and related medical application.

关键词： Dioscin Ishikawa cell Apoptosis Autophagy PI3K/AKT p53

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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 wa.g 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

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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

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