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Vertical variations in planar lamination of marine shale: Elucidating hydrodynamic changes during the Ordovician-Silurian transition on the Upper Yangtze Block

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Journal of Palaeogeography 2025年第1期14卷 221-244页

作者： Zhen-Sheng Shi Tian-Qi Zhou Hui-Bo Song Yong-Bin Niu Sha-Sha Sun Department of Unconventional Oil and Gas Research Institute of Petroleum Exploration and DevelopmentPetroChina College of Resources and Environment Henan Polytechnic University

The hydrodynamics and their evolution on the Upper Yangtze Block during the Ordovician-Silurian transition period remain unclear. The present study is an assessment of how regional and global events may have influenced the hydrodynamic evolution based on a planar lamination investigation of the shales from the Upper Yangtze Block. Analyses of large thin sections and argon-ion polished thin sections using field emission-scanning electron microscopy(FE-SEM) showed that there are four types of planar lamination, namely, silty graded planar lamination(SGPL), silt-clay graded planar lamination(SCGPL), silt-clay interlaminated planar lamination(SCIPL), and paper-like planar lamination(PPL). SGPL is formed by turbidity current with a flow speed less than 15 cm/s. SCGPL is formed by turbidity currents with a flow speed less than 15 cm/s for normal grading type and 15-25 cm/s for alternating grading type. SCIPL has a continuum of sparsely spaced type, closely spaced type, and alternating type, which is formed by bottom current with an increasing flow speed from 15 to 25 cm/s to above 25 cm/s. PPL can be divided into normal grading and composite grading types. The former is formed by vertical settling, while the latter is formed by bottom current with a flow speed of 5-15 cm/s. Vertically, types of planar lamination varied from SGPL to PPL and then SCIPL manifesting the waxing and waning of flow speed with a positive excursion at graptolite biozone Metabolograptus extraordinarius(WF4) and a negative excursion at graptolite biozone Persculptograptus persculptus(LM1). The sudden decrease in flow speed across Linxiang and graptolite biozone Paraorthograptus pacificus(WF3) and the subsequent progressive increase from graptolite biozone Akidograptus ascensus(LM2)to graptolite biozone Demirastrites triangulatus(LM6) and to graptolite biozone Stimulograptus sedgwickii(LM8) during deposition of the Ordovician-Silurian transition succession on the Upper Yangtze Block were linked to th

关键词： Planar lamination Wufeng Formation Longmaxi Formation Ocean circulation Black shale

Formation mechanism of deep natural hydrogen in the Sichuan Basin

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Science China Earth Sciences 2025年第2期68卷 581-597页

作者： Xiaomei WANG Kun HE Chunlong YANG Hao XIE Xiaobo WANG Yitong LYU Linfeng XIE Shuichang ZHANG research Institute of Petroleum Exploration&development PetroChinaBeijing 100083China Key Laboratory of Petroleum Geochemistry China National Petroleum CorporationBeijing 100083China International center for Isotope Effects research School of Earth Science and EngineeringNanjing UniversityNanjing 210023China

As a potential renewable and clean energy source,the distribution and exploration prospects of natural hydrogen have garnered widespread ***,the limitations in understanding the formation mechanisms and accumulation patterns of underground natural hydrogen have significantly constrained its efficient exploration and *** study reports H_(2)content and isotopes in natural gas from deep formations in sedimentary basins through geochemical analysis of 58 conventional gas samples from the Sinian to Triassic strata in the central Sichuan *** discovered that H_(2)content in deep natural gas in central Sichuan generally exceeds 0.1%,with a maximum of 1.6%,and hydrogen isotopes(δ^(2)H_(H_(2)))range from-850‰to-586‰.Analysis of the geological conditions,hydrogen generation mechanisms,and isotope fractionation characteristics in the study area confirms that microbial fermentation or in-situ organic matter cracking are not effective pathways for deep H_(2)*** with helium content and isotope analysis of the natural gas,it is inferred that the volcanic basement in the central Sichuan area is the potential source rock for natural H_(2)in the Sinian to Triassic ***,H_(2)originates from the radiolysis of water and hydrothermal reactions of Fe(Ⅱ)in the basement ***,a diffusion fractionation model reveals significant isotope fractionation during the migration and accumulation of deep H_(2)into sedimentary reservoirs,which lead to anomalously light δ^(2)H_(H_(2))in deep natural gas in central *** indicates that the underground natural hydrogen accumulation is in a long-term dynamic process,with simultaneous H_(2)accumulation and dissipation in the gas *** research not only elucidates the formation mechanism of deep H_(2)but also provides insights for the resource potential of natural hydrogen in sedimentary basins.

关键词： Natural H2 Sichuan Basin Hydrogen generation mechanism Isotope fractionation

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Non-existence of Shimura curves of Mumford type generically in the non-hyperelliptic locus

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Science China mathematics 2025年

作者： Xin Lü Shengli Tan Kang Zuo School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications(Ministry of Education) Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal University School of mathematics and Statistics Wuhan University Institut für Mathematik Universit?t Mainz

We show that there does not exist any Shimura curve with a strictly maximal Higgs field generically in the Torelli locus of non-hyperelliptic curves of genus g≥4. In particular, Shimura curves of Mumford type are not...

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Phenanthrene perturbs hematopoietic development and causes hematopoietic defects in zebrafish

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Journal of Environmental Sciences 2025年第5期151卷 573-581页

作者： Lingyu Ren Yue Wang Ying Ren Guangke Li Nan Sang College of Environment and Resource Research Center of Environment and HealthShanxi UniversityTaiyuan 030006China

Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and ***,it is still unknown whether it can affect the hematopoietic development in aquatic *** address this question,zebrafish(Danio rerio)were chronically exposed to Phe at different *** found that Phe caused structural damage to the renal tubules in the kidney,induced malformed erythrocytes in peripheral blood,and decreased the proportion of myeloid cells in adult zebrafish,suggesting possible negative impacts that Phe posed to hematopoietic ***,using in situ hybridization technology,we found that Phe decreased the expression of primitive hematopoietic marker genes,specifically gata1 and pu.1,accompanied by an obstruction of primitive erythrocyte ***,Phe impaired definitive hematopoiesis,increased aberrations of the transient hematopoietic site(PBI),and reduced the generation of hematopoietic stem cells,ultimately influencing the number of erythrocytes and myeloid *** findings suggested that Phe could induce hematopoietic toxicity in zebrafish embryos and pose unknown ecological risks.

关键词： Phenanthrene Zebrafish Hematopoietic development Hematopoietic defect

Managing virus diseases in citrus:Leveraging high-throughput sequencing for versatile applications

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Horticultural Plant Journal 2025年第1期11卷 57-68页

作者： Hongming Chen Zhiyou Xuan Lu Yang Song Zhang Mengji Cao Integrative Science center of Germplasm Creation in Western China(Chongqing)Science City Citrus Research InstituteSouthwest UniversityChongqing 400712China National Citrus Engineering research center Citrus Research InstituteSouthwest UniversityChongqing 400712China

In this review,the advantages and advances in applying high-throughput sequencing(HTS)in the management of viral diseases in citrus,along with some challenges,are discussed to provide perspectives on future *** the initial implementation of HTS in citrus virology,a substantial number of citrus viruses have been identified,with a notable increase in the last 7 *** acquisition of viral genomes and various HTS-based omics analyses serve as crucial pillars for advancing research in the etiology,epidemiology,pathology,evolution,ecology,and biotechnology of citrus *** has notably contributed to disease diagnosis,such as the diagnoses of concave gum and impietratura,as well as to the surveillance of new virus risks and the preparation of virus-free ***,certain inherent defects in HTS and coupled bioinformatics analysis,such as challenges with sequence assembly and the detection of viral dark matter,require improvement to enhance practical *** addition,the utilization of HTS for the systematic management of citrus viral diseases remains limited,and drawing insights from other virus-plant pathosystems while integrating emerging compatible techniques and ideas may broaden its specific applications.

关键词： Deep sequencing Virus epidemics Functional genomics CRISPR/Cas Virus-host interactions

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development and validation of a nomogram model for predicting overall survival in patients with gastric carcinoma

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World Journal of Gastrointestinal Oncology 2025年第2期17卷 132-143页

作者： Guan-Zhong Liang Xiao-Sheng Li Zu-Hai Hu Qian-Jie Xu Fang Wu Xiang-Lin Wu Hai-Ke Lei Chongqing Key Laboratory of Translational research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China Chongqing Cancer Multi-omics Big Data Application Engineering research center Chongqing University Cancer HospitalChongqing 400030China Department of Health Statistics School of Public HealthChongqing Medical UniversityChongqing 400016China research center for Medicine and Social development School of Public HealthChongqing Medical UniversityChongqing 400016China The research center of Big Data Chongqing University Cancer HospitalChongqing 400030China

BACKGROUND The prevalence and mortality rates of gastric carcinoma are disproportionately elevated in China,with the disease's intricate and varied characteristics further amplifying its health *** forecasting of overall survival(OS)is of paramount importance for the clinical management of individuals afflicted with this *** To develop and validate a nomogram model that provides precise gastric cancer prevention and treatment guidance and more accurate survival outcome prediction for patients with gastric *** Data analysis was conducted on samples collected from hospitalized gastric cancer patients between 2018 and *** absolute shrinkage and selection operator,univariate,and multivariate Cox regression analyses were employed to identify independent prognostic factors.A nomogram model was developed to predict gastric cancer patient *** model's predictability and discriminative ability were evaluated via receiver operating characteristic *** evaluate the clinical utility of the model,Kaplan-Meier and decision curve analyses were *** A total of ten independent prognostic factors were identified,including body mass index,tumor-node-metastasis(TNM)stage,radiation,chemotherapy,surgery,albumin,globulin,neutrophil count,lactate dehydrogenase,and platelet-to-lymphocyte *** area under the curve(AUC)values for the 1-,3-,and 5-year survival prediction in the training set were 0.843,0.850,and 0.821,*** AUC values were 0.864,0.820,and 0.786 for the 1-,3-,and 5-year survival prediction in the validation set,*** model exhibited strong discriminative ability,with both the time AUC and time C-index exceeding *** with TNM staging,the model demonstrated superior clinical ***,a nomogram was developed via a web-based *** This study established and validated a novel nomogram model for predicting the OS of gastric cancer patients,which demonstrat

关键词： Gastric carcinoma Prediction Overall survival Nomogram Prospective

Enhancing Entity Relationship Extraction in Dialogue Texts Using Hypergraph and Heterogeneous Graph

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Chinese Journal of Electronics 2025年第1期34卷 295-308页

作者： Shunmiao Zhang Siyuan Zheng Degen Huang Dan Li School of Computer Science and mathematics Fujian University of Technology Fujian Provincial Key Laboratory of Big Data Mining and applications Fujian University of Technology School of Computer Science and Technology Dalian University of Technology Elsevier

Dialogue-based relation extraction(DialogRE) aims to predict relationships between two entities in dialogue. Current approaches to dialogue relationship extraction grapple with long-distance entity relationships in dialogue data as well as complex entity relationships, such as a single entity with multiple types of connections. To address these issues, this paper presents a novel approach for dialogue relationship extraction termed the hypergraphs and heterogeneous graphs model(HG2G). This model introduces a two-tiered structure, comprising dialogue hypergraphs and dialogue heterogeneous graphs, to address the shortcomings of existing methods. The dialogue hypergraph establishes connections between similar nodes using hyper-edges and utilizes hypergraph convolution to capture multi-level features. Simultaneously, the dialogue heterogeneous graph connects nodes and edges of different types, employing heterogeneous graph convolution to aggregate cross-sentence information. Ultimately, the integrated nodes from both graphs capture the semantic nuances inherent in dialogue. Experimental results on the DialogRE dataset demonstrate that the HG2G model outperforms existing state-of-the-art methods.

关键词： Convolution Aggregates Semantics Feature extraction Data mining

Impact of land use change on carbon storage in the middle reaches of the Yellow River,China

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Journal of Arid Land 2025年第2期17卷 167-181页

作者： SHI Xiaoliang ZHANG Jie LIU Simin DING Hao CHEN Xi WANG Li ZHANG Dan College of Geomatics Xi'an University of Science and TechnologyXi'an 710054China China National Forestry-Grassland development research center Beijing 100714China

The implementation of long-term shelterbelt programs in the middle reaches of the Yellow River(MRYR),China not only has improved the overall ecological environment,but also has led to the changes of land use pattern,causing carbon storage ***,the relationship between carbon storage and land use change in the MRYR is not concerned,which results in the uncertainty in the simulation of carbon storage in this *** use changes directly affect the carbon storage capacity of ecosystems,and as an indicator reflecting the overall state of land use,land use degree has an important relationship with carbon *** this study,land use data and the integrated valuation of ecosystem services and trade-offs(InVEST)model were used to assess the trends in land use degree and carbon storage in the MRYR during *** potential impact index and the standard deviation ellipse(SDE)algorithm were applied to quantify and analyze the characteristics of the impact of land use changes on carbon ***,land use transitions that led to carbon storage variations and their spatial variations were *** results showed that:(1)the most significant periods of carbon storage changes and land use transitions were observed during 1990-1995 and 1995-2020,with the most changed areas locating in the east of Fenhe River and in northwestern Henan Province;(2)the positive impact of land use degree on carbon storage may be related to the environmental protection measures implemented along the Yellow River,while the negative impact may be associated with the expansion of construction land in plain areas;and(3)the conversion of other land use types to grassland was the primary factor affecting carbon storage changes during *** future land use planning,attention should be given to the direction of grassland conversion,and focus on reasonably limiting the development of construction *** enhance carbon storage,it will be crucial to increase the area

关键词： carbon storage land use degree integrated valuation of ecosystem services and trade-offs(InVEST)model potential impact standard deviation ellipse(SDE)

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On equidistribution theorems for multi-sequences of holomorphic line bundles

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Science China mathematics 2025年第2期68卷 285-298页

作者： Manli Liu Weixiong Mai Guokuan Shao Department of mathematics South China Agricultural UniversityGuangzhou 510642China Macao center for Mathematical Sciences Macao University of Science and TechnologyMacao 999078China School of mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai 519082China

Given several sequences of Hermitian holomorphic line bundles{(L_(kp),h_(kp))}_(p=1)^(∞),we establish the distribution of common zeros of random holomorphic sections of Lkp with respect to singular *** also study the... 详细信息

关键词： equidistribution random holomorphic section pseudo-effective line bundle current