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Microfabric features of microbial carbonates:experimental and natural evidence of mold holes and crusts

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Journal of Palaeogeography 2021年第3期10卷 321-333页

作者： Ya-Sheng Wu hong-xia jiang Ying Li Gong-Liang Yu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Institute of Paleontology Hebei GEO UniversityShijiazhuang 050031Hebei ProvinceChina Institute of Hydrobiology Chinese Academy of SciencesWuhan 430072Hubei ProvinceChina

Results of our study based on examination of induced precipitation of carbonate by a cyanobacterium, Lyngbya in the laboratory, and the analyses of microphotographs of both modern and ancient microbial carbonates,demonstrated the importance of recognition of mold holes and carbonate crusts in understanding microbial carbonates. In the experiment, only cyanobacteria Lyngbya can induce precipitation of carbonate, forming scattered grains on the surface of Lyngbya filaments. Carbonate crusts enclosing the old parts of the filaments were formed through aggregation of these scatter grains while mold holes were formed after decay of the filaments. Mainly based on the experiment, six different ways of microbial carbonate formation were recognized:(1) trapping without mold holes,(2) trapping with mold holes,(3) particle-forming induced-precipitation of carbonate,(4) discrete crustforming induced-precipitation of carbonate,(5) induced precipitation, forming tangled crusts that build a porous construction, and(6) induced precipitation, forming a dense construction. And mold holes and crusts can form in ways(4),(5), and(6). Examination of both modern microbial carbonates from the Shark Bay of Australia, Highborne Cay of Bahamas and the atoll of Kiritimati and the microbialites from the Cambrian dolostone sequence in Tarim,Xinjiang, China all demonstrated the limitation of recognizing only mesofabric features and importance of examining microfabric features for understanding of the genesis of the microbial carbonates and their proper classification. The shape, size and arrangement of the mold holes, crusts, and the features of the minerals filling in pores between the crusts, which are referred as the microfabric features here, are keys to better understand the formation and environments of both modern and ancient microbial carbonates.

关键词： Thrombolite Stromatolite Induced calcification Trapping Laminite Proclot

Coevality of the sea-level fall and main mass extinction in the Permian-Triassic transition in Xiushui, jiangxi Province, southern China

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Journal of Palaeogeography 2014年第3期3卷 309-322页

作者： Ya-Sheng Wu xiao-hong Yuan hong-xia jiang Li-Jing Liu Key Laboratory of Petroleum Resources Research CAS Institute of Geology and Geophysics Chinese Academy of Sciences Research Institute of Petroleum Exploration and Development PetroChina Huabei Oilfield Company

A continuous Permian-Triassic boundary （PTB） section has been found and studied for the first time in Xiushui, jiangxi Province, South China. Evidence for a large sealevel fall has been found in the horizon of 0.8 m below the PTB, from the beginning of Hindeodus changxingensis zone （correlatable to Hindeodus typicalis Zone of the Meishan section）. Sedimentary record indicates that the sea level kept at Iowstand, or occasionally rose slowly during the whole Hindeodus parvus zone, except another substantial sea-level fall in early H. parvus zone. It began a quick rise from the beginning of Isarcicella staeschei zone, kept rising for the whole/, staeschei zone, and probably caused the stagnation of sea water. The first severe change in the biota, marked by the sudden disappearance of all steno- tropic organisms such as fusulinids and dasycladacians, happened at the same time as the first sea-level fall, and is regarded as the first and main episode of the end-Permian mass extinction in this area. A microbe-dominated biota followed the first extinction, and spanned the late H. changxingensis zone and the whole H. parvus zone. All the microbes and some other eurytropic organisms including gastropods and ostracods disappeared at the end of the H. parvus zone, and the following biota in the/. staeschei zone is very simple. The coevality of the main sea-level fall and the main extinction episode might be causal： both of them might be caused by a drastic climatic cooling.

关键词： sea-level fall mass extinction Permian-Triassic boundary end-Permian climatic cooling South China

Macro-and microfeatures of Early Cambrian dolomitic microbialites from Tarim Basin, China

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Journal of Palaeogeography 2021年第1期10卷 19-38页

作者： Ying Li hong-xia jiang Ya-Sheng Wu Wen-Qing Pan Bao-Shou Zhang Chong-Hao Sun Guo Yang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Hebei GEO University Shijiazhuang 050031Hebei ProvinceChina Research Institute of Petroleum Exploration and Development Tarim Oilfield CompanyPetroChinaKorla 841000Xinjiang Uygur Autonomous RegionChina

The fabrics of microbialites preserved in limestones are generally better than in dolostones. What are the fabrics of the microbialites preserved in heavily dolomitized dolostones? This paper presents an example of a strongly dolomitized Cambrian microbialite profile. The xiaoerblak Formation(Cambrian Series 2 Stage 3 and lower Stage 4)of the Sugaitblak section in Aksu, Xinjiang Uygur Autonomous Region, China is mainly composed of microbial dolostones. Due to strong alteration by diagenesis, their features, formation and environments have not been fully understood. Here, based on detailed observation on outcrops and thin sections, we show that this formation comprises four kinds of microbialites: laminite, thrombolite, thrombolitic laminite, and Renalcis framestone, in five intervals(Interval I to Interval V). We identified three main types of microbialite fabrics, i.e., clotted fabric, laminated fabric and skeletal fabric, and established a high-resolution vertical evolution sequence of the microbialites. The clotted fabric and the laminated fabric were further divided into subtypes. We found that the original fabrics were mainly affected by dolomitization, recrystallization and dissolution, and the alteration degree of the microbialite fabric is stronger in the lower part of this formation. The laminated fabric has the strongest resistance to diagenesis,followed by the clotted fabric. Based on studies of different rock types and sedimentary structures, we concluded that the sedimentary environment of xiaoerblak Formation consists of three settings: a) Intervals I to III formed in restricted tidal flat environments, b) Interval IV and the lower part of Interval V in restricted deep subtidal environments, and c) upper part of Interval V in shallowing-up open subtidal environments.

关键词： Cambrian Microbialite Thrombolite Fabrics Laminite

Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method

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Petroleum Science 2024年第4期21卷 2769-2778页

作者： Yu Zhang hong-Yu Zhang Ran xia Si-Ao jiang Fang Wang College of Safety and Ocean Engineering China University of Petroleum China Academy of Aerospace Aerodynamics China Aerospace Science and Technology Group College of Engineering Science and Technology Shanghai Ocean University

The umbilical cable is a vital component of subsea production systems that provide power, chemical agents, control signals et al., and its requirement for reliability is exceedingly high. However, as the umbilical cable is a composite structure comprising multiple functional units, the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency. In this paper, the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed. The global dynamic analytical model is first established to determine the maximum tension load, then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM). Based on the mechanical analytical model, the reliability of umbilical cable under tension load is studied using response surface method(RSM) and Monte Carlo method. During the calculation process, a new tangent plane sampling method to calculate the response surface function(RSF) is proposed in this paper, which could make sampling points faster come close to the RSF curve, and it is proved that the calculation efficiency increases about 33% comparing with traditional method.

关键词： Umbilical cable Carbon fiber rod Failure analysis Response surface method Reliability

Halysis Høeg,1932—An ancestral tabulate coral from the Ordos Basin,North China

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Journal of Palaeogeography 2020年第4期9卷 480-494页

作者： Li-Jing Zheng hong-xia jiang Ya-Sheng Wu hong-Ping Bao Yue-Yang Zhang Jun-Feng Ren Zheng-Liang Huang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China China United Coalbed Methane Corporation LTDBeijing 100011China Institute of Paleontology Hebei Geo UniversityShijiazhuang 050031Hebei ProvinceChina University of Chinese Academy of Sciences Beijing 100049China Research Institute of Petroleum Exploration and Development Changqing OilfieldXi'an 710021Shaanxi ProvinceChina

The problematic calcareous microfossil Halysis is abundant in the Middle Ordovician Darriwilian Stage of the western edge of the Ordos Basin,North *** rich and well-preserved specimens of Halysis in this area facilitate detailed studies for its skeletal construction and tube *** differs from calcified cyanobacteria and calcareous red and green algae in morphology,skeletal construction and microstructure,as well as reproduction *** typically consists of multiple juxtaposed parallel tubes arranged in sheets(‘multiple-tube'type)or is just composed of one tube(‘single-tube'type).In‘multiple-tube'Halysis,tube fission by bifurcation results from the insertion of a microcrystalline wall at the center of a mother *** study demonstrates for the first time that the tube walls of Halysis have a laminofibrous(fibronormal)microstructure,composed of fibrous calcite perpendicular to wall surface,and recognizes the‘single-tube'type Halysis composed of one tube;in addition,for the first time,this study finds out that‘multiple-tube'Halysis develops buddings from the conjunction of two tubes and‘single-tube'Halysis shows wide-angle Y-shaped *** on these findings,this study further compares Halysis with tabulate *** appears stratigraphically earlier than Catenipora and Aulopora,and has a smaller tube size.‘Multiple-tube'Halysis resembles Catenipora and‘single-tube'Halysis resembles Aulopora in skeletal construction and microstructure,and in their tube walls of laminofibrous microstructure composed of fibrous calcite perpendicular to the tube wall *** and Halysis are both characterized by the absence of septal *** similarities suggest that Halysis may be the ancestor of Catenipora-like and Aulopora-like tabulate corals.

关键词： Halysis Morphology Taxonomic affinity Middle Ordovician Tabulate coral Wuhai Inner Mongolia

Low Concentration of Wenyang Tonglin Decoction Promotes Conjugation and Transfer of Drug-Resistant Plasmids among Heterologous Strains

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Chinese Journal of Integrative Medicine 2024年第8期30卷 721-728页

作者： WANG Bi-yan BU hong-shi xia Li-bo jiang xiang-yu TONG Yan-qing Department of Traditional Chinese Medicine Changchun University of Traditional Chinese MedicineChangchun130000China

Objective To investigate the effect of low concentration of Wenyang Tonglin Decoction(WTD)on the binding conditions of R45 plasmid conjugative transfer under liquid phase conjugation and its *** Escherichia coli CP9(R45)and Staphylococcus aureus RN450RF were cultured in medium containing WTD,and their minimum inhibitory concentration(MIC)values were *** promoter fusion technology,*** CP9(R45)containing a promoter fusion was obtained.β-Galactosidase activity of TrfAp and TrbBp was tested,and the mRNA expression of regulatory factors(TrbA,KorA,and KorB)was detected by real-time fluorescent quantitative polymerase chain *** The MIC of *** CP9(R45)was 400 g/L and that of *** RN450RF was 200 g/*** the drug concentration in the culture medium was 200 g/L,the highest number of conjugants was(3.47±0.20)×10^(7) CFU/mL At 90 h of conjugation,the maximum number of conjugants was(1.15±0.06)×10^(8) CFU/mL When the initial bacterial concentration was 10^(8) CFU/mL,the maximum number of conjugants was(3.47±0.20)×10^(7) CFU/*** the drug concentration was 200 g/L,theβ-galactosidase activity of TrfAp and TrbBp significantly increased;the relative quantification of TrbA,KorA and KorB were significantly *** Low concentration of WTD promoted the development of bacterial resistance by affecting promoters and inhibiting the expression of regulatory factors.

关键词： urinary tract infection Chinese medicine drug-resistant plasmid heterozygous strains conjugation transfer

Multiscale and Auto-Tuned Semi-Supervised Deep Subspace Clustering and Its Application in Brain Tumor Clustering

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Computers, Materials & Continua 2024年第6期79卷 4741-4762页

作者： Zhenyu Qian Yizhang jiang Zhou hong Lijun Huang Fengda Li Khin Wee Lai Kaijian xia School of Artificial Intelligence and Computer Science Jiangnan UniversityWuxi214122China Department of Medical Imaging The Changshu Affiliated Hospital of Soochow UniversitySuzhou215500China Department of Neurosurgery The Changshu Affiliated Hospital of Soochow UniversityChangshu215500China Department of Scientific Research The Changshu Affiliated Hospital of Soochow UniversitySuzhou215500China Changshu Key Laboratory of Medical Artificial Intelligence and Big Data Suzhou215500China Department of Biomedical Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur50603Malaysia

In this paper,we introduce a novel Multi-scale and Auto-tuned Semi-supervised Deep Subspace Clustering(MAS-DSC)algorithm,aimed at addressing the challenges of deep subspace clustering in high-dimensional real-world data,particularly in the field of medical *** deep subspace clustering algorithms,which are mostly unsupervised,are limited in their ability to effectively utilize the inherent prior knowledge in medical *** MAS-DSC algorithm incorporates a semi-supervised learning framework that uses a small amount of labeled data to guide the clustering process,thereby enhancing the discriminative power of the feature ***,the multi-scale feature extraction mechanism is designed to adapt to the complexity of medical imaging data,resulting in more accurate clustering *** address the difficulty of hyperparameter selection in deep subspace clustering,this paper employs a Bayesian optimization algorithm for adaptive tuning of hyperparameters related to subspace clustering,prior knowledge constraints,and model loss *** experiments on standard clustering datasets,including ORL,Coil20,and Coil100,validate the effectiveness of the MAS-DSC *** results show that with its multi-scale network structure and Bayesian hyperparameter optimization,MAS-DSC achieves excellent clustering results on these ***,tests on a brain tumor dataset demonstrate the robustness of the algorithm and its ability to leverage prior knowledge for efficient feature extraction and enhanced clustering performance within a semi-supervised learning framework.

关键词： Deep subspace clustering multiscale network structure automatic hyperparameter tuning semi-supervised medical image clustering

Percutaneous transhepatic cholangioscopy-assisted biliary polypectomy for local palliative treatment of intraductal papillary neoplasm of the bile duct

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1821-1832页

作者： Xu Ren Yong-Ping Qu Chun-Lan Zhu xiao-hong Xu hong jiang Yi-xia Lu hong-Peng Xue Digestive Disease Hospital of Heilongjiang Provincial Hospital Heilongjiang Provincial Clinical Medical Research Center for Minimally Invasive Diagnosis and Treatment of Pancreaticobiliary DiseasesHarbin 150001Heilongjiang ProvinceChina Digestive Endoscopy Center of Heilongjiang Provincial Hospital Heilongjiang Provincial Clinical Medical Research Center for Minimally Invasive Diagnosis and Treatment of Pancreaticobiliary DiseasesHarbin 150001Heilongjiang ProvinceChina Second Department of Gastroenterology Digestive Disease Hospital of Heilongjiang Provincial Hospitaland Heilongjiang Provincial Clinical Medical Research Center for Minimally Invasive Diagnosis and Treatment of Pancreaticobiliary DiseasesHarbin 150001Heilongjiang ProvinceChina Department of Pathology Heilongjiang Provincial HospitalHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)is a premalignant biliarytype epithelial neoplasm with intraductal papillary or villous *** reported local palliative therapeutic modalities,including endoscopic nasobiliary drainage,stenting and biliary curettage,endoscopic biliary polypectomy,percutaneous biliary drainage,laser ablation,argon plasma coagulation,photodynamic therapy,and radiofrequency ablation to relieve mechanical obstruction are limited with weaknesses and *** have applied percutaneous transhepatic cholangioscopy(PTCS)-assisted biliary polypectomy(PTCS-BP)technique for the management of IPNB including mucin-hypersecreting cast-like and polypoid type tumors since *** To assess the technical feasibility,efficacy,and safety of PTCS-BP for local palliative treatment of *** Patients with mucin-hypersecreting cast-like or polypoid type IPNB and receiving PTCS-BP between September 2010 and December 2019 were ***-BP was performed by using a half-moon type snare with a soft stainless-steel wire,and the tumor was snared and resected with *** primary outcome was its feasibility,indicated by technical *** secondary outcomes were efficacy,including therapeutic success,curative resection,and clinical success,and *** Five patients(four with mucin-hypersecreting cast-like type and one with polypoid type IPNB)were ***-and high-grade intraepithelial neoplasia(HGIN)and recurrent IPNB with invasive carcinoma were observed in one,two,and two patients,*** cholangitis and/or obstructive jaundice were presented in all four patients with mucin-hypersecreting cast-like type *** five patients achieved technical success of *** patients(three with mucin-hypersecreting cast-like type and one with polypoid type IPNB)obtained therapeutic success;one with mucin-hypersecreting cast-like type tumors in the intrahepatic small bile duct and HGIN h

关键词： Intraductal papillary neoplasm of the bile duct Percutaneous transhepatic cholangioscopy Biliary polypectomy Feasibility Efficacy

A Nonparametric Model Checking Test for Functional Linear Composite Quantile Regression Models

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Journal of Systems Science & Complexity 2024年第4期37卷 1714-1737页

作者： xia Lili DU jiang ZHANG Zhongzhan Faculty of Science Beijing University of TechnologyBeijing 100124China

This paper is focused on the goodness-of-fit test of the functional linear composite quantile regression model.A nonparametric test is proposed by using the orthogonality of the residual and its conditional expectation under the null *** proposed test statistic has an asymptotic standard normal distribution under the null hypothesis,and tends to infinity in probability under the alternative hypothesis,which implies the consistency of the ***,it is proved that the test statistic converges to a normal distribution with nonzero mean under a local alternative *** simulations are reported,and the results show that the proposed test has proper sizes and is sensitive to the considered model *** proposed methods are also applied to two real datasets.

关键词： Composite quantile regression consistent test functional data nonparametric test quadratic form