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Propagation and Dispersion Characteristics of Scholte Wave in VTI Media with the Presence of Irregular Seabed

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Journal of Earth Science 2024年第2期35卷 722-725页

作者： xiaobo Liu Yun Wang Jianlei Zhang Haifeng Chen Hua Zhang School of Ocean Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Polar Geology and Marine Mineral Resources China University of GeosciencesBeijing 100083China School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China Research&Development Center BGP IncCNPCZhuozhou 072751China National Engineering Research Center for Oil and Gas Exploration Computer Software Beijing 100080China

INTRODUCTION Surface waves propagating along the seafloor are general ly called Scholte waves,and were first discovered and studied in the early 1950s(Kugler et al.,2005;Buchen and Ben-Hador,1996).Scholte waves exhibit a dispersion phenomenon,which implies that their velocity varies with ***-frequency Scholte waves can propagate over long distances on the seabed with little attenuation(Bohlen et al.,2004).The particle mo tion of Scholte waves in a solid medium changes from a retro grade to a prograde ellipse(Klein et al.,2005;McMechan and Yedlin,1981).

关键词： seabed Dispersion implies

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Biosynthetic pathway of prescription cucurbitacin IIa and high-level production of key triterpenoid intermediates in engineered yeast and tobacco

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Plant Communications 2024年第6期5卷 154-172页

作者： Geng Chen Zhaokuan Guo Yanyu Shu Yan Zhao Lei Qiu Shaofeng Duan Yuan Lin Simei He xiaobo Li Xiaolin Feng Guisheng Xiang Bo Nian Yina Wang Zhiyuan Li Chongkang yang yang Shi Yingchun Lu Guanze Liu Shengchao yang Guanghui Zhang Bing Hao State Key Laboratory of Conservation and Utilization of Bio-resources in Yunnan The Key Laboratory of Medicinal Plant Biology of Yunnan ProvinceNational&Local Joint Engineering Research Center on Germplasms Innovation&Utilization of Chinese Medicinal Materials in Southwest ChinaYunnan Agricultural UniversityKunming 650201China Yunnan Characteristic Plant Extraction Laboratory KunmingYunnan 650106China

Cucurbitacin IIa is a triterpenoid isolated exclusively from Hemsleya plants and a non-steroidal anti-inflammatory drug that functions as the main ingredient of prescription Hemslecin capsules and tablets in *** biology provides new strategies for production of such valuable cucurbitacins at a large scale;however,the biosynthetic pathway of cucurbitacin IIa has been unknown,and the heterologous production of cucurbitacins in galactose medium has been expensive and low *** this study,we characterized the functions of genes encoding two squalene epoxidases(HcSE1-2),six oxidosqualene cyclases(HcOSC1-6),two CYP450s(HcCYP87D20 and HcCYP81Q59),and an acyltransferase(HcAT1)in cucurbitacin IIa biosynthesis by heterologous expression in Saccharomyces cerevisiae and Nicotiana *** achieved high-level production of the key cucurbitacin precursor 11-carbonyl-20b-hydroxy-Cuol from glucose in yeast via modular engineering of the mevalonate pathway and optimization of P450 expression *** resulting yields of 46.41 mg/l 11-carbonyl-20b-hydroxy-Cuol and 126.47 mg/l total cucurbitacin triterpenoids in shake flasks are the highest yields yet reported from engineered ***,production of 11-carbonyl-20b-hydroxy-Cuol by transient gene expression in tobacco resulted in yields of 1.28 mg/g dry weight in *** work reveals the key genes involved in biosynthesis of prescription cucurbitacin IIa and demonstrates that engineered yeast cultivated with glucose can produce high yields of key triterpenoid *** describe a low-cost and highly efficient platform for rapid screening of candidate genes and high-yield production of pharmacological triterpenoids.

关键词： cucurbitacin IIa oxidosqualene cyclase OSC 11-carbonyl-20b-hydroxy-Cuol Saccharomyces cerevisiae Nicotiana benthamiana Hemsleya chinensis

Morroniside from Corni Fructus ameliorates type 2 diabetes in mice by regulating intestinal microbiota dysbiosis

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Food Science and Human Wellness 2024年

作者： Xueqi Tang Yilin Bai Yinxia Wu Yue yang xiaobo Yu Jing Chen Xiaochang Xue Jiefang Kang National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry， The Ministry of Education College of Life Sciences， Shaanxi Normal University

As one of the most common metabolic diseases， type 2 diabetes (T2D) has become a public health concern with rising global prevalence. Corni fructus (CF)， a traditional Chinese herb utilized for centuries as homologous medicinal and food resources， has been widely used to treat glucose and lipid metabolism disorders. However， as a core active ingredient of CF， whether and how morroniside (MOR) improves T2D is still unclear. This study aimed to explore the pathways by which MOR ameliorates T2D in mice induced by high-fat diet (HFD) and low-dose streptozotocin (STZ) through 16S rRNA gene sequencing. We found that MOR treatment significantly ameliorated body weight loss， hyperglycemia， hyperlipidemia and insulin resistance in T2D mice. In addition， MOR remarkably improved inflammation- and oxidative stress-driven hepatic and pancreatic injuries in the model mice. Mechanistically， MOR rehabilitated the dysregulated diversity and constitution of the gut microbiota in T2D mice， with significant changes in relative abundance in genus such as Lactobacillus， Lachnospiraceae＿NK4A136＿Group， and Lachnospiraceae＿UCG-006 which are believed to be highly correlated with serum parameters and insulin resistance in mice with T2D. Therefore， we infer that MOR improves T2D at least partially by maintaining the host microbiota homeostasis， and MOR may be a promising candidate for T2D treatment.

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Robust Cross-Linked Na_(3)V_(2)(PO_(4))_(2)F_(3) Full Sodium-Ion Batteries

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Energy & Environmental Materials 2024年第1期7卷 9-20页

作者： Jinqiang Gao Ye Tian Lianshan Ni Baowei Wang Kangyu Zou Yingchang yang Ying Wang Craig E.Banks Dou Zhang Kechao Zhou Huan Liu Wentao Deng Guoqiang Zou Hongshuai Hou xiaobo Ji College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China College of Material and Chemical Engineering Tongren UniversityTongren 554300China Department of Chemistry The Chinese University of Hong KongShatinN.T.Hong Kong S.A.R.China Faculty of Science and Engineering Manchester Metropolitan UniversityManchester UK State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Materials Science and Engineering Hunan Provincial Key Lab of Advanced Materials for New Energy Storage and ConversionHunan University of Science and TechnologyXiangtan 411201China School of Materials and Engineering Zhengzhou UniversityZhengzhou 450001China

Sodium-ion batteries(SIBs)have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium-ion batteries(LIBs).Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)as a common cathode of SIBs,features the merits of high operating voltage,small volume change and favorable specific energy ***,it suffers from poor cycling stability and rate performance induced by its low intrinsic ***,we propose an ingenious strategy targeting superior SIBs through cross-linked NVPF with multi-dimensional nanocarbon frameworks composed of amorphous carbon and carbon nanotubes(NVPF@C@CNTs).This rational design ensures favorable particle size for shortened sodium ion transmission pathway as well as improved electronic transfer network,thus leading to enhanced charge transfer kinetics and superior cycling *** from this unique structure,significantly improved electrochemical properties are obtained,including high specific capacity(126.9 mAh g^(-1)at 1 C,1 C=128 mA g^(-1))and remarkably improved long-term cycling stability with 93.9%capacity retention after 1000 cycles at 20 *** energy density of 286.8 Wh kg^(-1)can be reached for full cells with hard carbon as anode(NVPF@C@CNTs//HC).Additionally,the electrochemical performance of the full cell at high temperature is also investigated(95.3 mAh g^(-1)after 100 cycles at 1 C at 50℃).Such nanoscale dual-carbon networks engineering and thorough discussion of ion diffusion kinetics might make contributions to accelerating the process of phosphate cathodes in SIBs for large-scale energy storages.

关键词： dual-nanocarbon networks full sodium-ion battery ion transfer kinetics Na_(3)V_(2)(PO_(4))_(2)F_(3) NASICON structure

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Contemporary strategies and approaches for characterizing composition and enhancing biofilm penetration targeting bacterial extracellular polymeric substances

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Journal of Pharmaceutical Analysis 2024年第4期14卷 506-524页

作者： Lan Lu Yuting Zhao Mingxing Li xiaobo Wang Jie Zhu Li Liao Jingya Wang Key Laboratory of Medicinal and Edible Plants Resources Development of Sichuan Education Department Sichuan Industrial Institute of AntibioticsSchool of PharmacyChengdu UniversityChengdu610000China Meishan Pharmaceutical Vocational College School of PharmacyMeishanSichuan620200China Laboratory of Molecular Pharmacology Department of PharmacologySchool of PharmacySouthwest Medical UniversityLuzhouSichuan646000China Hepatobiliary Surgery Langzhong People's HospitalLangzhongSichuan646000China

Extracellular polymeric substances(EPS)constitutes crucial elements within bacterial biofilms,facili-tating accelerated antimicrobial resistance and conferring defense against the host's immune *** precise and effective antibiofilm approaches and strategies,tailored to the specific charac-teristics of EPS composition,can offer valuable insights for the creation of novel antimicrobial ***,in turn,holds the potential to mitigate the alarming issue of bacterial drug *** analysis of EPS compositions relies heavily on colorimetric approaches with a significant bias,which is likely due to the selection of a standard compound and the cross-interference of various EPS *** the pivotal role of EPS in biofilm functionality,it is imperative for EPS research to delve deeper into the analysis of intricate compositions,moving beyond the current focus on polymeric *** ne-cessitates a shift from heavy reliance on colorimetric analytic methods to more comprehensive and nuanced analytical *** this study,we have provided a comprehensive summary of existing analytical methods utilized in the characterization of EPS ***,novel strategies aimed at targeting EPS to enhance biofilm penetration were explored,with a specific focus on high-lighting the limitations associated with colorimetric ***,we have outlined the challenges faced in identifying additional components of EPS and propose a prospective research plan to address these *** review has the potential to guide future researchers in the search for novel compounds capable of suppressing EPS,thereby inhibiting biofilm *** insight opens up a new avenue for exploration within this research domain.

关键词： Analytic strategies and approaches Composition characterization Extracellular polymeric substances(EPS) Promoting biofilm penetration

Gradient honeycomb metastructure with broadband microwave absorption and effective mechanical resistance

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Nano Materials Science 2024年第4期6卷 456-466页

作者： Dongmeng Li Xia Zheng Hao Gu xiaobo Xuan Bing Liu Hongquan Feng Fuheng Zhang Shanghai Radio Equipment Research Institute

Multifunctional metastructure integrated broadband microwave absorption and effective mechanical resistance has attracted much attention. However, multifunctional performance is limited by the lack of theoretical approaches to integrated design. Herein, a multi-layer impedance gradient honeycomb(MIGH) was designed through theoretical analysis and simulation calculation, and fabricated using 3D printing technique. A theoretical calculation strategy for impedance gradient structure was established based on the electromagnetic parameter equivalent method and the multi-layer finite iterative method. The impedance of MIGH was analyzed by the theoretical calculation strategy to resolve the broadband absorption. Intrinsic loss mechanism of matrix materials and distributions of electric fields, magnetic fields and power loss were analyzed to investigate the absorption mechanism. Experimental results indicated that a 15 mm thick designed metastructure can achieve the absorption more than 88.9% in the frequency range of 2-18 GHz. Moreover, equivalent mechanical parameters of MIGH was calculated by integral method according to the Y-shaped model. Finite Element analysis of stress distributions were carried out to predict the deformation behavior. Mechanical tests demonstrate that MIGH achieved the compression modulus of 22.89 MPa and flexure modulus of 17.05 MPa. The integration of broadband electromagnetic absorption and effective mechanical resistance was achieved by the proposed design principle and fabrication methodology.

关键词： Multifunctional metastructure Broadband microwave absorption Impedance gradient calculation Mechanical characteristics Finite element analysis

Natural variation of GmFNSII-2 contributes to drought resistance by modulating enzyme activity in soybean

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The Crop Journal 2024年第2期12卷 529-539页

作者： Huihui Gao Pengcheng Wei Yongzhe Gu Pengbin Tang Yifan Shen Lei yang Linxin Dong Haowei Zheng Kuo Shu Mayamiko Masangano Bin Dong Long Miao Jiajia Li Lijuan Qiu xiaobo Wang School of Agronomy Anhui Agricultural UniversityHefei 230036AnhuiChina State Key Laboratory of Crop Gene Resources and Breeding The National Key Facility for Crop Gene Resources and Genetic Improvement(NFCRI)/Key Laboratory of Crop Gene Resource and Germplasm Enhancement(MOA)Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

As an essential crop that provides vegetable oil and protein,soybean(Glycine max(L.)Merr.)is widely planted all over the ***,the scarcity of water resources worldwide has seriously impacted on the quality and yield of *** address this,exploring excellent genes for improving drought resistance in soybean is *** this study,we identified natural variations of GmFNSII-2(flavone synthase II)significantly affect the drought resistance of *** sequence analysis of GmFNSII-2 in 632 cultivated and 44 wild soybeans nine haplotypes were *** full-length allele GmFNSII-2^(C),but not the truncated allele GmFNSII-2^(A) possessing a nonsense nucleotide variation,increased enzyme *** research found that GmDREB3,known to increase soybean drought resistance,bound to the promoter region of GmFNSII-2^(C).GmDREB3 positively regulated the expression of GmFNSII-2^(C),increased flavone synthase abundance and improved the drought ***,a singlebase mutation in the GmFNSII-2^(C) promoter generated an additional drought response element(CCCCT),which had stronger interaction strength with GmDREB3 and increased its transcriptional activity under drought *** frequency of drought-resistant soybean varieties with Hap 1(Pro:GmFNSII-2^(C))has increased,suggesting that this haplotype may be selected during soybean *** summary,GmFNSII-2^(C) could be used for molecular breeding of drought-tolerant soybean.

关键词： Drought stress Flavone synthase GmFNSII-2 Natural variation Drought response element

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Immunosuppression and phenotypic plasticity in an atlas of human hepatocholangiocarcinoma

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Hepatobiliary Surgery and Nutrition 2024年第4期13卷 586-603,I0002-I0014页

作者： Yiran Li Ziyu Xun Junyu Long Huishan Sun Xu yang Yanyu Wang Yunchao Wang Jingnan Xue Nan Zhang Junwei Zhang Jin Bian Jie Shi xiaobo yang Hanping Wang Haitao Zhao State Key Laboratory of Complex Severe and Rare Diseases Department of Liver SurgeryPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical College(CAMS&PUMC)BeijingChina Division of Pulmonary and Critical Care Medicine State Key Laboratory of Complex Severe and Rare DiseasesChinese Academy of Medical Sciences and Peking Union Medical College(CAMS&PUMC)BeijingChina

Background:Hepatocholangiocarcinoma(H-ChC)has the clinicopathological features of both hepatocellular carcinoma(HCC)and intrahepatic cholangiocarcinoma(iCCA)and is a more aggressive subtype of primary hepatic carcinoma than HCC or ***:We sequenced 91,112 single-cell transcriptomes from 16 human samples to elucidate the molecular mechanisms underlying the coexistence of HCC and iCCA components in ***:We observed two molecular subtypes of H-ChC at the whole-transcriptome level(CHP and CIP),where a metabolically active tumour cell subpopulation enriched in CHP was characterized by a cellular pre-differentiation *** define the heterogeneity of tumours and their associated microenvironments,we observe greater tumour diversity in H-ChC than HCC and iCCA.H-ChC exhibits weaker immune cell infiltration and greater CD8+exhausted T cell(Tex)dysfunction than HCC and *** we defined two broad cell states of 6,852 CD8+Tex cells:GZMK+CD8+Tex cells and terminal CD8+Tex ***+CD8+Tex cells exhibited higher infiltration of after treatment in H-ChC,the effector scores and expression of the immune checkpoints of them greatly increased after immunotherapy,which indicated that H-ChC might be more sensitive than HCC or iCCA to ***:In this paper,H-ChC was explored,hoping to contribute to the study of mixed tumours in other cancers.

关键词： Hepatocholangiocarcinoma(H-ChC) biphenotypic plasticity CD8+Tex cells immunosuppression

A U-Shaped Network-Based Grid Tagging Model for Chinese Named Entity Recognition

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Computers, Materials & Continua 2024年第6期79卷 4149-4167页

作者： Yan Xiang Xuedong Zhao Junjun Guo Zhiliang Shi Enbang Chen xiaobo Zhang Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650504China Yunnan Key Laboratory of Artificial Intelligence Kunming University of Science and TechnologyKunming650500China Kunming Enersun Technology Co. Ltd.Kunming650217China

Chinese named entity recognition(CNER)has received widespread attention as an important task of Chinese information *** previous research has focused on individually studying flat CNER,overlapped CNER,or discontinuous ***,a unified CNER is often needed in real-world *** studies have shown that grid tagging-based methods based on character-pair relationship classification hold great potential for achieving unified ***,how to enrich Chinese character-pair grid representations and capture deeper dependencies between character pairs to improve entity recognition performance remains an unresolved *** this study,we enhance the character-pair grid representation by incorporating both local and global ***,we introduce a new approach by considering the character-pair grid representation matrix as a specialized image,converting the classification of character-pair relationships into a pixel-level semantic segmentation *** devise a U-shaped network to extract multi-scale and deeper semantic information from the grid image,allowing for a more comprehensive understanding of associative features between character *** approach leads to improved accuracy in predicting their relationships,ultimately enhancing entity recognition *** conducted experiments on two public CNER datasets in the biomedical domain,namely CMeEE-V2 and *** results demonstrate the effectiveness of our approach,which achieves F1-score improvements of 7.29 percentage points and 1.64 percentage points compared to the current state-of-the-art(SOTA)models,respectively.

关键词： Chinese named entity recognition character-pair relation classification grid tagging U-shaped segmentation network