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Three-dimensional internal multiple elimination in complex structures using Marchenko autofocusing theory

Petroleum Science 2025年第1期22卷 222-233页

作者： Pei-Nan Bao Ying Shi Xin-Min Shang hong-Xian Liang wei-hong wang School of Earth Sciences Northeast Petroleum University Geophysical Research Institute of Shengli Oilfield Sinopec

Internal multiples are commonly present in seismic data due to variations in velocity or density of subsurface media. They can reduce the signal-to-noise ratio of seismic data and degrade the quality of the image. With the development of seismic exploration into deep and ultradeep events, especially those from complex targets in the western region of China, the internal multiple eliminations become increasingly challenging. Currently, three-dimensional(3D) seismic data are primarily used for oil and gas target recognition and drilling. Effectively eliminating internal multiples in 3D seismic data of complex structures and mitigating their adverse effects is crucial for enhancing the success rate of drilling. In this study, we propose an internal multiple prediction algorithm for 3D seismic data in complex structures using the Marchenko autofocusing theory. This method can predict the accurate internal multiples of time difference without an accurate velocity model and the implementation process mainly consists of several steps. Firstly, simulating direct waves with a 3D macroscopic velocity ***, using direct waves and 3D full seismic acquisition records to obtain the upgoing and downgoing Green's functions between the virtual source point and surface. Thirdly, constructing internal multiples of the relevant layers by upgoing and downgoing Green's functions. Finally, utilizing the adaptive matching subtraction method to remove predicted internal multiples from the original data to obtain seismic records without multiples. Compared with the two-dimensional(2D) Marchenko algorithm, the performance of the 3D Marchenko algorithm for internal multiple prediction has been significantly enhanced, resulting in higher computational accuracy. Numerical simulation test results indicate that our proposed method can effectively eliminate internal multiples in 3D seismic data,thereby exhibiting important theoretical and industrial application value.

关键词： Marchenko Internal multiple elimination Autofocusing Three-dimensional seismic data

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New measurement of ^(63)Cu(γ,n)^(62)Cu cross-section using quasi-monoenergeticγ-ray beam

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Nuclear Science and Techniques 2025年第2期36卷 131-140页

作者： Zhi-Cai Li Zi-Rui Hao Qian-Kun Sun Yu-Long Shen Long-Xiang Liu Hang-Hua Xu Yue Zhang Pu Jiao Meng-Die Zhou Yu-Xuan Yang Sheng Jin Kai-Jie Chen Zhen-wei wang Shan Ye Xin-Xiang Li Chun-wang Ma hong-wei wang Gong-Tao Fan Wen Luo School of Nuclear Science and Technology University of South ChinaHengyang 421001China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Science Beijing 100049China School of Physics Henan Normal UniversityXinxiang 453007China China Institute of Atomic Energy Beijing 102413China Institute of Nuclear Science and Technology Henan Academy of SciencesZhengzhou 450046China

We present new data on the^(63)Cu(γ,n)cross-section studied using a quasi-monochromatic and energy-tunableγbeam produced at the Shanghai Laser Electron Gamma Source to resolve the long-standing discrepancy between existing measurements and evaluations of this *** an unfolding iteration method,^(63)Cu(γ,n)data were obtained with an uncertainty of less than 4%,and the inconsistencies between the available experimental data were ***γ-ray strength function of^(63)Cu(γ,n)was successfully extracted as an experimental *** further calculated the cross-section of the radiative neutron capture reaction^(62)Cu(n,γ)using the TALYS *** calculation method enables the extraction of(n,γ)cross-sections for unstable nuclides.

关键词： ^(63)Cu(γ n)reaction Cross-section data Quasi-monochromaticbeam Radiative neutron capture reaction

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Structure of precursor micro RNA＇s terminal loop regulates human Dicer＇s dicing activity by switching DExH/D domain

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Protein & Cell 2015年第3期6卷 185-193页

作者： Zhongmin Liu Jia wang Gang Li hong-wei wang Department of Biochemistry and Molecular Biology School of Basic Medical Sciences Peking University Health Science Center Beijing 100191 China Tsinghua-Peking Joint Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China

Almost all pre-miRNAs in eukaryotic cytoplasm are recognized and processed into double-stranded microRNAs by the endonuclease Dicer protein comprising of multiple domains. As a key player in the small RNA induced gene silencing pathway, the major domains of Dicer are conserved among different species with the exception of the N-terminal components. Human Dicer＇s N-terminal domain has been shown to play an autoinhibitory function of the protein＇s dicing activity. Such an auto-inhibition can be released when the human Dicer protein dimerizes with its partner protein, such as TRBP, PACT through the N-terminal DExH/D （ATPase- helicase） domain. The typical feature of a pre-miRNA contains a terminal loop and a stem duplex, which bind to human Dicer＇s DExH/D （ATPase-helicase） domain and PAZ domain respectively during the dicing reaction. Here, we show that pre-miRNA＇s terminal loop can regulate human Dicer＇s enzymatic activity by interacting with the DExH/D （ATPase-helicase） domain. We found that various editing products of pre-miR-151 by the ADAR1P110 protein, an A-to-I editing enzyme that modifies pre-miRNAs sequence, have different terminal loop structures and different activity regulatory effects on human Dicer. Single particle electron microscopy reconstruction revealed that pre-miRNAs with different terminal loop structures induce human Dicer＇s DExH/D （ATPase-helicase） domain into different conformational states, in correlation with their activity regulatory effects.

关键词： human Dicer DExH/D (ATPase-helicase)domain pre-miRNA-151 A-to-I editing single particle electron microscopy

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An improved method for internal multiple elimination using the theory of virtual events

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Petroleum Science 2022年第6期19卷 2663-2674页

作者： Pei-Nan Bao Ying Shi wei-hong wang wei Zhang Zhe-Jun Pan Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development Ministry of EducationNortheast Petroleum UniversityDaqingHeilongjiang163318China School of Earth Sciences Northeast Petroleum UniversityDaqingHeilongjiang163318China School of Information and Communication Engineering Faculty of Electronic and Information EngineeringXi'an Jiaotong UniversityXi’anShaanxi710049China National Engineering Laboratory for Offshore Oil Exploration Xi'an Jiaotong UniversityXi’anShaanxi710049China

Compared with first-order surface-related multiples from marine data,the onshore internal multiples are weaker and are always combined with a hazy and occasionally strong interference *** is usually difficult to discriminate these events from complex targets and highly scattering overburdens,especially when the primary energy from deep layers is weaker than that from shallow *** internal multiple elimination is even more challenging due to the fact that the velocity and energy difference between primary reflections and internal multiples is *** this study,we propose an improved method which formulates the elimination of the internal multiples as an optimization problem and develops a convolution factor *** generated internal multiples at all interfaces are obtained using the convolution factor T through iterative inversion of the initial multiple *** predicted internal multiples are removed from seismic data through ***,several synthetic experiments are conducted to validate the effectiveness of our *** results of our study indicate that compared with the traditional virtual events method,the improved method simplifies the multiple prediction process in which internal multiples generated from each interface are built through iterative inversion,thus reducing the calculation cost,improving the accuracy,and enhancing the adaptability of field data.

关键词： Internal multiple Convolution factor Elimination Virtual events

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Hybrid absorbing boundary condition based on transmitting boundary and its application in 3D fractional viscoacoustic modeling

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Petroleum Science 2023年第2期20卷 840-856页

作者： Song-Ling Li Ying Shi Ning wang wei-hong wang Xuan Ke School of Earth Sciences Northeast Petroleum UniversityDaqingHeilongjiang 163318China

An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computational cost and hardware capability limitations, numerical simulations are often performed within a finite domain. Thus, an adequate absorbing boundary condition (ABC) is indispensable for obtaining accurate numerical simulation results. In this study, we develop a hybrid ABC based on a transmitting boundary, which is referred to as THABC, to eliminate artificial boundary reflections in 3D second-order fractional viscoacoustic numerical simulations. Furthermore, we propose an adaptive weighted coefficient to reconcile the transmitting and viscoacoustic wavefields in THABC. Through several numerical examples, we determine that the proposed THABC approach is characterized by the following benefits. First, with the same number of absorbing layers, THABC exhibits a better ability in eliminating boundary reflection than traditional ABC schemes. Second, THABC is more effective in computation, since it only requires the wavefields at the current and last time steps to solve the transmitting formula within the absorbing layers. Benefiting from a simple but effective combination between the transmitting equation and the second-order wave equation, our scheme performs well in the 3D fractional Laplacian viscoacoustic numerical simulation.

关键词： Hybrid absorbing boundary Numerical simulation Transmitting boundary Fractional viscoacoustic wave equation

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Peroxisome proliferator-activated receptor γ and colorectal cancer

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World Journal of Gastrointestinal Oncology 2010年第3期2卷 159-164页

作者： Yun Dai wei-hong wang Yun Dai Wei-Hong Wang Department of Gastroenterology Peking University First Hospital Beijing 100034 China.

Peroxisome proliferator-activated receptors(PPARs) are members of the nuclear hormone receptor superfamily and ligand-activated transcription ***γ plays an important role in adipocyte differentiation,lipid storage and energy dissipation in adipose tissue,and is involved in the control of inflammatory reactions as well as in glucose metabolism through the improvement of insulin *** evidence has demonstrated that activation of PPARγ has an antineoplastic effect in tumors,including colorectal *** expression of PPARγ is detected in human colon cancer cell lines and *** review describes the molecular mechanisms by which PPARγ regulates tumorigenesis in colorectal cancer,and examines current clinical trials evaluating PPARγ agonists as therapeutic agents for colorectal cancer.

关键词： Colorectal cancer Peroxisome proliferator-activated receptors Ligand Tumor suppression

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Study on the flow structure in curved open channels with suspended vegetation using multi relaxation time lattice Boltzmann method

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Journal of Hydrodynamics 2024年第2期36卷 300-315页

作者： He-fang Jing Qiao-ling Zhang wei-hong wang Zong-ning Zhang School of Mathematics and Information Science North Minzu UniversityYinchuan750021China School of Civil Engineering North Minzu UniversityYinchuan750021China Department of Basic Courses Zhengzhou University of Science and TechnologyZhengzhou450064China

Suspended vegetation in rivers,lakes,reservoirs and canals can change flow structure,which will in turn affect the sediment transport and cause the variation of water ecological *** order to study the characteristics of bend flow through suspended vegetation,three-dimensional numerical simulations are carried out by using the multi-relaxation-time lattice Boltzmann method(MRT-LBM).The drag force induced by vegetation is added in the velocity correction in the equilibrium distribution and a hybrid format combined bounce and specular reflection scheme is applied in the solid-fluid *** the validation of this model,six cases are designed to conduct the numerical simulations according to the root depth and the arrangement of *** simulated results show that the suspended vegetation can redistribute the flow structure in curved open *** the arrangement of suspended vegetation,the main flow moves to the side without vegetation,and the distribution of velocity tends to be balanced when vegetation is arranged on the entire cross section,the range of circulating current is reduced from the whole cross section to the local position without vegetation,however,the circulating current can still exist in the curve where the suspended vegetation enters less than half of the water *** addition,it can also be concluded that the suspended vegetation can affect the lateral gradient of flow velocity,and the bed shear stress in the curved channel.

关键词： Multi-relaxation-time lattice Boltzmann method(MRT-LBM) suspended vegetation curved open channel circulating current bed shearstress

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Ibuprofen induced drug loaded polymeric micelles

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Chinese Chemical Letters 2011年第9期22卷 1123-1126页

作者： Song wei Tan hong Jun wang Ke Hua Tu hong Liang Jiang Li Qun wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027 China

Three model drugs with different function groups were chosen to dialyze with dextran-graft-poly （N-isopropylacrylalaide）. Only ibuprofen could induce the formation of drug loaded micelles, which was contirmed with dynamic light scattering and transmission electron microscope. Hydrogen-bonding between the amide groups of poly （N-isopropylacrylamide） and the carboxyl groups of ibuprofen was driving force for the drug-loaded micelle. It was also found thai the diameter of the ibuprofen-loaded micelles changed reversibly against temperature.

关键词： Micellc Thernlo-sensilive Drug Hydrogen-bonding Poly (N-isopropylacryhlmide)

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Impact of STAT4 gene silencing on the expression profile of proteins in EL-4 cells

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Chinese Science Bulletin 2009年第18期54卷 3265-3270页

作者： wei XiaoLi NI hong wang QingShan XIANG Rong wang Yue School of Medicine Nankai University Tianjin 3000-71 China

The signal transducers and activators of transcription (STATs) have diverse biological functions and are involved in cell differentiation, proliferation, development, apoptosis and inflammation. Several constitutively activated STATs have been observed in a wide variety of human cancer cell lines and primary tumor cells, including blood malignancies and solid neoplasias. Although regulatory T (Treg) cells induce immune tolerance by suppressing host immune responses against selfor nonself-antigens, thus playing critical roles in preventing autoimmune diseases, they might inhibit antitumor im-munity and promote tumor growth. Our previous findings suggest that the supernatant from STAT4silenced tumor cell culture can significantly increase the ratio of CD4+ CD25+ Foxp3+ regulatory T cells among splenic cells in vitro, when compared to that from normal tumor cell culture. In the present study, we identified that the mouse lymphoma cell line EL-4 expressed a high level of STAT4, and silencing of STAT4 by siRNA did not change the expression levels of TGF-β and IL-10 in EL-4 cells. Two-dimensional electrophoresis was conducted to examine the difference of expression profiles of proteins between normal and STAT4-silenced EL4 cells. Some of the protein which has been changed may induce CD4+ CD25+ Foxp3+ regulatory T cells in vitro.

关键词：细胞分化细胞蛋白表达谱基因沉默转录激活因子转化生长因子肿瘤细胞发光

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Effects of different concentrations of nicotinamide on hematopoietic stem cells cultured in vitro

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World Journal of Stem Cells 2024年第2期16卷 163-175页

作者： Yan Ren Yan-Ni Cui hong-wei wang The Second Clinical Medical College Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology The Second Hospital of Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology Key Laboratory of Molecular Diagnosis and Treatment of Blood Diseases in Shanxi ProvinceTaiyuan 030001Shanxi ProvinceChina

BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital ***(NAM)can promote HSC expansion ex vivo,but its effect on hematopoietic stem and progenitor cells(HSPCs,CD34^(+)CD38)and functional subtypes of HSCs-shortterm repopulating HSCs(ST-HSCs,CD34^(+)CD38CD45RACD49f^(+))and long-term repopulating HSCs(LT-HSCs,CD34^(+)CD38CD45RACD49f^(+)CD90^(+))is not yet *** a sirtuin 1(SIRT1)inhibitor,NAM participates in regulating cell adhesion,polarity,migration,proliferation,and ***,SIRT1 exhibits dual effects by promoting or inhibiting differentiation in different tissues or *** propose that the concentration of NAM may influence proliferation,differentiation,and SIRT1 signaling of *** To evaluate the effects and underlying mechanisms of action of different concentrations of NAM on HSC proliferation and *** CD34^(+)cells were purified from umbilical cord blood using MacsCD34 beads,and cultured for 10-12 d in a serum-free medium supplemented with cytokines,with different concentrations of NAM added according to experimental *** cytometry was used to detect phenotype,cell cycle distribution,and apoptosis of the cultured ***-time polymerase chain reaction was used to detect the transcription levels of target genes encoding stemness-related factors,che mokines,components of hypoxia pathways,and antioxidant ***-dihydro-fluorescein diacetate probes were used to evaluate intracellular production of reactive oxygen species(ROS).Determination of the effect of different culture conditions on the balance of cytokine by cytometric bead *** Compared with the control group,the proportion and expansion folds of HSPCs(CD34^(+)CD38)incubated with 5 mmol/L or 10 mmol/L NAM were significantly increased(all P<0.05).The ST-HSCs ratio and fold expansion of the 5 mmol/L NAM group were significantly

关键词： Hematopoietic stem cells Nicotinamide Concentration Proliferation Differentiation Sirtuin 1

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