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ASYMPTOTIC THEORY FOR THE CIRCUIT ENVELOPE ANALYSIS

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Journal of Computational Mathematics 2024年第4期42卷 955-978页

作者： Chunxiong Zheng Xianwei wen Jinyu zhang Zhenya Zhou College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830046China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Empyrean Software Empyrean Technology Co.Ltd.Beijing 100102China

Asymptotic theory for the circuit envelope analysis is developed in this paper.A typical feature of circuit envelope analysis is the existence of two significantly distinct timescales:one is the fast timescale of carrier wave,and the other is the slow timescale of modulation *** first perform pro forma asymptotic analysis for both the driven and autonomous *** resorting to the Floquet theory of periodic operators,we make a rigorous justification for first-order asymptotic *** turns out that these asymptotic results are valid at least on the slow *** speed up the computation of asymptotic approximations,we propose a periodization technique,which renders the possibility of utilizing the NUFFT *** experiments are presented,and the results validate the theoretical findings.

关键词： Asymptotic analysis Circuit envelope analysis Floquet theory Singularly perturbed problem

Observation of spectral lines in the exceptional GRB 221009A

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu zhang Shao-Lin Xiong Ji-Rong Mao Shuang-Nan zhang Wang-Chen Xue Chao Zheng Jia-Cong Liu Zhen zhang Xi-Lu Wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song Zheng-Hua An Ce Cai xin-Qiao Li wen-Xi Peng wen-Jun Tan Chen-Wei Wang Xiang-Yang wen Yue Wang Shuo Xiao Fan zhang Peng zhang Shi-Jie Zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line

Deformation mechanism and hydrocarbon significance of Eocene organic-rich fine-grained soft sediments in the Leijia Region,Liaohe Depression

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Frontiers of Earth Science 2024年第1期18卷 83-97页

作者： Yijie wen Jianguo zhang Shu TAO Chenyu CAI School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Strategy Evaluation for Shale Gas(Ministry of Land Resources) China University of Geosciences(Beijing)Beijing 100083China School of Foreign Languages China University of Geosciences(Beijing)Beijing 100083China

The deformation structure of soft sediments has always been a research hotspot,which is of great significance for analyzing the tectonic and sedimentary evolution background of a basin,as well as the physical properties of *** studies have reported that a large number of soft sediment deformation structures are developed in the western part of Liaohe *** this study,through core observation and thin section identification,various types of deformation structures are identified in the core samples which are collected from the upper Es4 in the Leijia region,western sag of Liaohe depression,such as liquefied dikes,liquefied breccia,convoluted laminae,annular bedding,synsedimentary faults,vein structures,*** on the characteristics of core structure,single well profile and continuous well profile,combined with the regional background,this study clarifies that the deformation structure of soft sediments in the study area is mainly caused by seismic *** is found that the permeability and porosity of deformation layers in the study area are higher than those of the undeformation layers,which proves that the deformation structure of soft sediments has a good effect on improving the physical properties of reservoirs.

关键词： soft sediment deformation structure Liaohe depression organic-rich fine-grained soft sediments hydrocarbon significance

Heavier Group 14 Congeners of Metalla-isobenzenes:Access to Metalla-isosilabenzene and Metalla-isogermabenzene by One-Pot Reactions

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Chinese Journal of Chemistry 2024年第10期42卷 1121-1127页

作者： Jinyu Zhao Yapeng Cai xin Yang Hong zhang Department of Chemistry Xiamen UniversityXiamenFujian 361005China

Metalla-isosilabenzenes and metalla-isogermabenzenes have been successfully synthesized by the formal[5+1]-cycloaddition of diethynylsilane or diethynylgermane with simple metal *** is the first example of a heavier Group 14 metalla-isobenzene isomer bearing a cumulative double bond motif within a *** novel complexes were fully characterized by NMR spectroscopy and single-crystal X-ray diffraction *** stabilization of the cyclic metal-vinylidene complexes has been analyzed using density functional theory(DFT)*** the metalla-isosilabenzenes bearing Si—H bond were treated with the trityl salt as a hydride scavenger,the formation of silylium cation was observed *** of metalla-isosilabenzenes and metalla-isogermabenzenes can readily undergo migratory insertion reactions to furnish siloles or germoles.

关键词： Metalla-isosilabenzene Metalla-isogermabenzene Density functional calculations Cycloaddition Metallacycles

Humanβ-defensin-1 affects the mammalian target of rapamycin pathway and autophagy in colon cancer cells through long noncoding RNA TCONS_00014506

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1465-1478页

作者： Yu-xin Zhao Yan Cui xin-Hong Li wen-Hong Yang Shi-Xiang An Jia-Xian Cui Min-Yu zhang Jing-Kun Lu Xuan zhang Xiu-Mei Wang Li-Li Bao Peng-Wei Zhao Department of Anesthesiology Inner Mongolia Chest HospitalThe Fourth HospitalHohhot 010035Inner Mongolia Autonomous RegionChina College of Humanities and Education Inner Mongolia Medical UniversityHohhot 010059Inner Mongolia Autonomous RegionChina Department of Radiotherapy The Affiliated Hospital of Inner Mongolia Medical UniversityHohhot 010059Inner Mongolia Autonomous RegionChina School of Basic Medical Science Inner Mongolia Medical UniversityHohhot 010059Inner Mongolia Autonomous RegionChina Department of Medical Oncology The Affiliated Cancer Hospital of Inner Mongolia Medical UniversityHohhot 010050Inner Mongolia Autonomous RegionChina

BACKGROUND Colorectal cancer has a low 5-year survival rate and high ***β-defensin-1(hBD-1)may play an integral function in the innate immune system,contributing to the recognition and destruction of cancer *** non-coding RNAs(lncRNAs)are involved in the process of cell differentiation and *** To investigate the effect of hBD-1 on the mammalian target of rapamycin(mTOR)pathway and autophagy in human colon cancer SW620 *** CCK8 assay was utilized for the detection of cell proliferation and determination of the optimal drug *** formation assay was employed to assess the effect of hBD-1 on SW620 cell *** was used to screen potentially biologically significant lncRNAs related to the mTOR ***,p-mTOR(Ser2448),Beclin1,and LC3II/I expression levels in SW620 cells were assessed through Western blot *** hBD-1 inhibited the proliferative ability of SW620 cells,as evidenced by the reduction in the colony formation capacity of SW620 cells upon exposure to ***-1 decreased the expression of p-mTOR(Ser2448)protein and increased the expression of Beclin1 and LC3II/I ***,bioinformatics analysis identified seven lncRNAs(2 upregulated and 5 downregulated)related to the mTOR *** lncRNA TCONS_00014506 was ultimately *** the inhibition of the lncRNA TCONS_00014506,exposure to hBD-1 inhibited p-mTOR(Ser2448)and promoted Beclin1 and LC3II/I protein *** hBD-1 inhibits the mTOR pathway and promotes autophagy by upregulating the expression of the lncRNA TCONS_00014506 in SW620 cells.

关键词： Colon cancer Humanβ-defensin-1 LncRNA Mammalian target of rapamycin Autophagy

Effects of pyraclostrobin on growth,oxidative stress,and gene expression in relation to stress and ATP-binding cassette transporters in Tetrahymena thermophila

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Journal of Oceanology and Limnology 2024年第1期42卷 150-162页

作者： Yang LIU Jiale zhang Peng XIAO xin LIU Yisifu MA Jing zhang Bangjun zhang Henan International Joint Laboratory of Aquatic Ecotoxicology and Health Protection Xinxiang 453007China College of Life Sciences Henan Normal UniversityXinxiang 453007China Journal of Henan Normal University Xinxiang 453007China College of Life and Environmental Science Wenzhou UniversityWenzhou 325035China Department of Ecosystem Studies School of Environmental ScienceUniversity of Shiga PrefectureShiga 522-8533Japan

Pyraclostrobin(PYR),a widely used fungicide,has negative effects on fish and algae,but its toxicity in protozoa remains *** this study,the effects of PYR on the growth,oxidative stress,and gene expression related to stress and ATP-binding cassette(ABC)transporters in Tetrahymena thermophila were *** result showed that the 96-h IC_(50)of PYR against *** was 17.2 mg/***,PYR inhibited the growth of *** in concentration-or time-dependent manner.A morphological study revealed that the shape and size of *** changed,and damage of cell membrane surface was observed by scanning electron microscopy after 96 h of PYR *** activities of superoxide dismutase(SOD)and catalase(CAT)increased throughout the *** contrast,the glutathione(GSH)content was increased at 24 h and 48 h of exposure and decreased at 96 ***,a significant increase in malondialdehyde(MDA)level was observed in *** after96 h of ***,PYR upregulated the HSP703,HSP705,GPx2,and ABAC15 gene expression in the 0.1–5-mg/L groups and downregulated the HSP704,HSP90,TGR,and ABCC52 mRNA levels at 96 h of *** results suggest that PYR may exert adverse effects on *** by inducing oxidative stress and changing the gene expression related to ABC transporters and stress,which may enrich the understanding of the toxicity mechanism of PYR in aquatic organisms and provide reference data for aquatic ecological risk assessments.

关键词： pyraclostrobin Tetrahymena thermophila growth oxidative stress gene expression

Basilic vein variation encountered during surgery for arm vein port:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2086-2091页

作者： Cheng-Da Hu Rui Lv Ya-xin Zhao Ming-Hao zhang Hong-Dou Zeng Yi-wen Mao Department of Breast Surgery The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly *** vein variation usually presents without any clinical symptoms and is often regarded as a benign *** case was a patient with congenital basilic vein variation encountered during surgery for an infusion *** SUMMARY We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port *** peculiarity has hitherto remained undescribed in the *** offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its *** conducted a comprehensive review of analogous cases in the literature,offering pertinent therapeutic recommendations and solutions,with the aim of enhancing the efficacy and safety of future arm port *** Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy,so as not to affect subsequent treatment.

关键词： Totally implantable venous access ports Arm ports Venous variation Postoperative breast cancer Systematic review Case report

Novel Shaped Sweeping Jet for Improved Film Cooling and Anti-Deposition Performance

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Journal of Thermal Science 2024年第6期33卷 2089-2096页

作者： ZHOU wenwu WANG Kechen zhang Tianluan wen xin PENG Di LIU Yingzheng Key Lab of Education Ministry for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong University Gas Turbine Research Institute Shanghai Jiao Tong University

The present study proposed a shaped sweeping jet(SJ) that possesses the merits of both SJ and shaped hole,which demonstrates significantly improved cooling effectiveness and anti-deposition *** to a classical 777 shaped hole,the shaped SJ exhibits a maximum enhancement of 70% in cooling effectiveness and a maximum reduction of 28% in particle deposition height,*** to the periodic oscillation of coolant jet and higher streamwise jet momentum,the shaped SJ can provide much wider coolant coverage and therefore sweep the adhesive particle away from the *** study is the first attempt to reconcile the performance of film cooling and particle anti-deposition simultaneously,which offers a promising design concept for future engine cooling.

关键词： film cooling multi-perspective scanning particle deposition pressure sensitive paint sweeping jet

Solvent-free carbon sphere nanofluids towards intelligent lubrication regulation

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Friction 2024年第1期12卷 95-109页

作者： Sheng zhang wen LI Xiaoliang MA Xiaoqiang FAN Minhao ZHU Tribology Research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

By simply switching the electrical circuit installed on steel/steel contact,the tribological behaviors of nanofluids(NFs)can be regulated in real time,thereby achieving the desired performance of friction reduction and wear ***,solvent-free carbon spherical nanofluids(C-NFs)were successfully prepared for intelligent lubrication regulation.C-NFs with excellent lubrication performance can immediately reduce the coefficient of friction(COF)despite applying a weak electric potential(1.5 V).Moreover,polyethylene glycol 400(PEG400)containing 5.0 wt%C-NFs remained responsive to electrical stimulation under the intermittent voltage application with an average coefficient of friction(ACOF)reduction of 20.8%over *** intelligent lubrication regulation of C-NFs under an external electric field(EEF)mainly depends on the orderly arranged double-electric adsorption film of ion canopy-adsorbed carbon spheres(CSs).The intermittent electrical application can continuously reinforce the adsorption film and its durability for real-time controlling the sliding ***-stimulation-responsive intelligent lubricants provide a new technical support for realizing intelligent stepless control of devices.

关键词： solvent-free carbon spherical nanofluids(C-NFs) intelligent lubrication regulation lubrication performance adsorption film