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Three-stage niobium mineralization at Bayan Obo, China

National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang li Yu liu xiao-xiao ling li-Guang Wu li Yang Lan Yang Bo Yang Yong-gang Zhao Xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

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Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： ZHANG Ying xiao gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and errors.Quality assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same time.Therefore,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge graph.Among them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among entities.In this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness assumptions.The purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China

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Petroleum Science 2024年第3期21卷 1488-1507页

作者： gang li Xian-Ming xiao Bo-Wei Cheng Chen-gang Lu Yue Feng Dong-Sheng li School of Energy Resources China University of Geosciences (Beijing) Frontiers Science Center for Deep-time Digital Earth China University of Geosciences (Beijing)

The Lower Cambrian shale gas in the western Hubei area, South China has a great resource prospect, but the gas-in-place（GIP） content in different sedimentary facies varies widely, and the relevant mechanism has been not well understood. In the present study, two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area, representing the deep-water shelf facies and shallowwater platform facies, respectively, were investigated on the differences of pore types, pore structure and methane adsorption capacity between them, and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed. The results show that the organic matter（OM） pores in the YD4 shale samples are dominant, while the inorganic mineral（IM） pores in the YD5 shale samples are primary, with underdeveloped OM pores. The pore specific surface area（SSA） and pore volume（PV） of the YD4 shale samples are mainly from micropores and mesopores, respectively,while those of the YD5 shale samples are mainly from micropores and macropores, respectively. The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples, with a maximum absolute adsorption capacity of 3.13 cm3/g and 1.31 cm3/g in average,respectively. Compared with the shallow-water platform shale, the deep-water shelf shale has a higher TOC content, a better kerogen type and more developed OM pores, which is the main mechanism for its higher adsorption capacity. The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 3 4 m3/t within a depth range of 1000—4000 m, with shale gas exploration and development potential, while the shallow-water platform shale has normally a GIP content of little shale gas potential. Considering the geological and geochemical conditions of shale gas formation and preservation, the deep-w

关键词： Lower Cambrian shale Deep-water shelf facies Shallow-water platform facies Pore structure Methane adsorption Gas-in-place content Controlling factor

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Correlation between serum markers and transjugular intrahepatic portosystemic shunt prognosis in patients with cirrhotic ascites

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 481-490页

作者： xiao-gang Hu xiao-Xian Yang Jun Lu gang li Jian-Ji Dai Jia-Min Wang Yi Deng Rui Feng Department of Interventional Radiology The Affiliated Jinhua HospitalZhejiang University School of MedicineJinhua 321000Zhejiang ProvinceChina Medical College Jinhua PolytechnicJinhua 321017Zhejiang ProvinceChina Department of Interventional Medicine Zhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Individuals with refractory ascites in the context of liver cirrhosis typically face an adverse prognosis.The transjugular intrahepatic portosystemic shunt(TIPS)is an efficacious intervention,but there is a lack of reliable tools for postoperative pro-gnosis assessment.Previously utilized clinical biochemical markers,such as the serum albumin concentration(Alb),sodium(Na+)concentration,and serum creatinine(Scr),have limited predictive value.Therefore,the quest for novel,specific biomarkers to evaluate the post-TIPS prognosis in patients with liver cirrhosis and refractory ascites holds significant practical importance.A retrospective analysis was conducted on 75 patients with liver cirrhosis and refractory ascites who underwent TIPS at our institution from August 2019 to August 2021.These patients were followed up regularly for two years,and the death toll was meticulously documented.The patients were allocated into a survival group(n=45 patients)or a deceased group(n=30 patients)based on their prognosis status.The clinical data of the two groups were collected,and Child-Pugh scores and MELD scores were calculated for analysis.Spearman correlation analysis was carried out to evaluate the correlation of prognosis with Child-Pugh grade,MELD score,and Cys C level.Additionally,a multiple-factor analysis utilizing the Cox proportional hazard model was used to identify independent risk factors affecting the post-TIPS prognosis of patients with liver cirrhosis and refractory ascites.The receiver operating characteristic curve(ROC)ascertained the predictive value of the Cys C concen-tration,Child-Pugh grade,and MELD score for the prognosis of liver cirrhosis with refractory ascites in post-TIPS patients.RESULTS During a 2-year follow-up period,among 75 patients with liver cirrhosis and refractory ascites who underwent TIPS treatment,30 patients(40.00%)passed away.The deceased cohort exhibited heightened aspartate aminotrans-ferase,alanine aminotransferase,total bilirubin,Scr,prothrombin time,Cys C,internationa

关键词： liver cirrhosis Refractory ascites Transjugular intrahepatic portosystemic shunt Cystatin C

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Efficacy of scraping therapy on blood pressure and sleep quality in stage Ⅰ and Ⅱ essential hypertension: A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第1期22卷 12-21页

作者： Zheng-gang Zhu Jian-ru Wang xiao-yan Pan School of Nursing Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Health Sciences Universiti Sains MalaysiaKubang Kerian 16150KelantanMalaysia Department of Cardiovascular Medicine the First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina

Background Scraping therapy is widely used in treating stage I and II essential hypertension in China.However,there has been no systematic evaluation of the efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential hypertension.Search strategy Seven electronic databases(PubMed,Scopus,Cochrane library,Web of Science,EBSCO,China National Knowledge Infrastructure and Wanfang Data electronic databases)were searched from inception to December 2022.Based on the principle of combining subject words with text words,the search strategy was constructed around search terms for“scraping therapy,”“scraping,”“Guasha,”“Gua sha,”“hypertension,”and“high blood pressure”during the database searches.Inclusion criteria Randomized controlled trials(RCTs)were included if they recruited patients with stage I and II essential hypertension and included a scraping therapy intervention.The intervention group received antihypertensive drugs and scraping therapy,while the control group only took antihypertensive drugs.Data extraction and analysis Review Manager 5.4.0 and STATA 15.1 were used to enter all the relevant outcome variables to conduct the meta-analysis.The quality of the selected RCTs was assessed using the PEDro scale.The sensitivity analysis was carried out by iteratively excluding individual studies and repeating the analysis to determine the stability of the findings and identify any studies with greater influence on the outcome.Subgroup analysis was performed to find the source of heterogeneity.Funnel plots were used to evaluate the publication bias of included studies.Results Nine RCTs including 765 participants were selected.Meta-analysis showed that scraping therapy combined with medication had an advantage over the use of medication alone in lowering systolic blood pressure(mean difference[MD]=?5.09,95%confidence interval[CI]=?6.50 to?3.67,Plic blood pressure(MD=?2.66,95%CI=?3.17 to?2.14,Plity in mid

关键词： Scraping therapy Essential hypertension Efficacy Blood pressure Sleep quality Systematic review Meta-analysis

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Synthesis of Organofluorine Compounds with Acylsilanes

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Chinese Journal of Chemistry 2024年第8期42卷 887-902页

作者： Youyuan Guo gang Zhou xiao Shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan University299 Bayi RoadWuhanHubei430072 China

Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material chemistry.In this review,we summarize the investigations on the synthesis of organofluorine compounds with acylsilanes.For the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-difluoroketones.For the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine compounds.In general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.

关键词： Acylsilanes Organofluorine compounds Brook rearrangement Radical rearrangement β-Fluoride elimination Asymmetric catalysis Photocatalysis Defluoroalkylation

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Early results of the integrative epigenomic-transcriptomic landscape of colorectal adenoma and cancer

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 414-435页

作者： You-Wang Lu Zhao-li Ding Rui Mao Gui-gang Zhao Yu-Qi He xiao-Lu li Jiang liu Department of Dermatology and Venereology The First Affiliated Hospital of Kunming Medical UniversityKunming 650032Yunnan ProvinceChina Kunming Biological Diversity Regional Center of Large Apparatus and Equipments Public Technical Service CenterKunming Institute of ZoologyKunming 650223Yunnan ProvinceChina School of Stomatology Kunming Medical UniversityKunming 650500Yunnan ProvinceChina Genome Center of Biodiversity Kunming Institute of ZoologyChinese Academy of ScienceKunming 650223Yunnan ProvinceChina Department of Reproduction and Genetics The First Affiliated Hospital of Kunming Medical UniversityKunming 650032Yunnan ProvinceChina

BACKGROUND Aberrant methylation is common during the initiation and progression of colorectal cancer(CRC),and detecting these changes that occur during early adenoma(ADE)formation and CRC progression has clinical value.AIM To identify potential DNA methylation markers specific to ADE and CRC.METHODS Here,we performed SeqCap targeted bisulfite sequencing and RNA-seq analysis of colorectal ADE and CRC samples to profile the epigenomic-transcriptomic landscape.RESULTS Comparing 22 CRC and 25 ADE samples,global methylation was higher in the former,but both showed similar methylation patterns regarding differentially methylated gene positions,chromatin signatures,and repeated elements.High-grade CRC tended to exhibit elevated methylation levels in gene promoter regions compared to those in low-grade CRC.Combined with RNA-seq gene expression data,we identified 14 methylation-regulated differentially expressed genes,of which only AGTR1 and NECAB1 methylation had prognostic significance.CONCLUSION Our results suggest that genome-wide alterations in DNA methylation occur during the early stages of CRC and demonstrate the methylation signatures associated with colorectal ADEs and CRC,suggesting prognostic biomarkers for CRC.

关键词： Colorectal cancer Epigenomic alteration Transcriptome Methylation-regulated differentially expressed genes

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Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1022-1038页

作者： xiao Xue Deyu Zhou Xiangning Yu gang Wang Juanjuan li Xia Xie lizhen Cui Fei-Yue Wang the School of Computer Software College of Intelligence and ComputingTianjin UniversityTianjin 300350China the School of Software and the Joint SDUNTU Centre for Artificial Intelligence Research(C-FAIR) Shandong UniversityJinan 250101China the Information School Xi’an University of Financial and EconomicsXi’an 710100China the State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Hainan University Haikou 570228China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 1001901China

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

关键词： Agent-based modeling computational experiments cyber-physical-social systems(CPSS) generative deduction generative experiments meta model

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A Transient-Pressure-Based Numerical Approach for Interlayer Identification in Sand Reservoirs

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Fluid Dynamics & Materials Processing 2024年第3期20卷 641-659页

作者： Hao Luo Haibo Deng Honglin xiao Shaoyang Geng Fu Hou gang Luo Yaqi li Tight Oil and Gas Exploration and Development Project Department PetroChina Southwest Oil and Gas Field CompanyChengdu610051China Energy College Chengdu University of TechnologyChengdu610059China

Almost all sandstone reservoirs contain interlayers. The identification and characterization of these interlayers iscritical for minimizing the uncertainty associated with oilfield development and improving oil and gas recovery.Identifying interlayers outside wells using identification methods based on logging data and machine learning isdifficult and seismic-based identification techniques are expensive. Herein, a numerical model based on seepageand well-testing theories is introduced to identify interlayers using transient pressure data. The proposed modelrelies on the open-source MATLAB Reservoir Simulation Toolbox. The effects of the interlayer thickness, position,and width on the pressure response are thoroughly investigated. A procedure for inverting interlayer parametersin the reservoir using the bottom-hole pressure is also proposed. This method uses only transient pressuredata during well testing and can effectively identify the interlayer distribution near the wellbore at an extremelylow cost. The reliability of the model is verified using effective oilfield examples.

关键词： Sand reservoir interlayer identification transient pressure analysis numerical well test

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Intestinal tuberculosis with small bowel stricture and hemorrhage as the predominant manifestation: Three case reports

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 248-256页

作者： gang Huang Kang-Kang Wu xiao-Na li Jing-Hua Kuai Ai-Jun Zhang Department of Gastroenterology Qilu Hospital(Qingdao)Cheeloo College of MedicineShandong UniversityQingdao 266000Shandong ProvinceChina

BACKGROUND Intestinal tuberculosis is a chronic disease caused by Mycobacterium tuberculosis that mainly affects the ileum and cecum.Small bowel tuberculosis,characterized by predominant involvement of the small intestine,is an extremely rare condition with highly atypical clinical presentations,making diagnosis even more challenging.CASE SUMMARY We report three cases of small intestinal tuberculosis,two of the patients pre-sented primarily with abdominal pain,and one presented with gastrointestinal bleeding.All patients underwent blood tests and imaging examinations.Small bowel endoscopy(SBE)revealed that the main lesions in these patients were in-testinal stenosis or gastrointestinal bleeding caused by small intestinal ulcers.One patient ultimately underwent surgical treatment.Following a complex diagnostic process and comprehensive analysis,all patients were confirmed to have small intestinal tuberculosis and received standard antituberculosis treatment,leading to an improvement in their condition.CONCLUSION Patients with SBTs present with nonspecific symptoms such as abdominal pain,weight loss,and occasional gastrointestinal bleeding.Accurate diagnosis requires a thorough evaluation of clinical symptoms and various tests to avoid misdiagno-sis and complications.

关键词： Intestinal tuberculosis Gastrointestinal hemorrhage Small bowel endoscopy Case report

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