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Sliced Average Variance Estimation for Tensor Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 630-655页

作者： Chuan-quan li pei-wen xiao Chao YING xiao-hui liU School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Biostatistics and Medical Informatics University of Wisconsin MadisonMadison 53726USA

Tensor data have been widely used in many fields,e.g.,modern biomedical imaging,chemometrics,and economics,but often suffer from some common issues as in high dimensional *** to find their low-dimensional latent structure has been of great interest for *** this end,we develop two efficient tensor sufficient dimension reduction methods based on the sliced average variance estimation(SAVE)to estimate the corresponding dimension reduction *** first one,entitled tensor sliced average variance estimation(TSAVE),works well when the response is discrete or takes finite values,but is not■consistent for continuous response;the second one,named bias-correction tensor sliced average variance estimation(CTSAVE),is a de-biased version of the TSAVE *** asymptotic properties of both methods are derived under mild *** and real data examples are also provided to show the superiority of the efficiency of the developed methods.

关键词： tensor data sliced average variance estimation sufficient dimension reduction central subspace

Effect of forging on the microstructure and texture of a high Nb containing γ-TiAl alloy

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Journal of Central South University 2024年第6期31卷 1763-1773页

作者： TAO hui li hui-zhong WANG li ZHOU Rui CHE Yi-xuan CHEN yong-hui liANG xiao-peng School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Key Laboratory of Nonferrous Metal Materials Science and Engineering Central South UniversityChangsha 410083China Department of Materials Science and Engineering City University of Hong KongKowloon 999077Hong KongChina

The effect of forging on the microstructure and texture evolution of a high Nb containing Ti-45Al-7Nb-0.3W(at.%)alloy was investigated by X-ray diffractometer(XRD),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).The results show that the as-cast alloy is mainly composed of α_(2)/γ lamellar colonies with a mean size of 70μm,but the hot-forged pancake displays a near duplex microstructure(DP).Kinking and bending of lamellar colonies,deformation twinning and dynamic recrystallization(DRX)occur during hot ***,dense dislocations in theβphase after forging suggest that the high-temperature β phase with a disordered structure is favorable for improving the hot-workability of the *** the common TiAl casting texture,the solidification process of the investigated as-cast alloy with high Nb content is completely via the β phase region,resulting in the formation of a110>γ fiber texture where the110>γ aligns parallel to the heat-flow *** comparison,the relatively strong1>and weak2>texture components in the as-forged alloy are attributed to the deformation *** annealing,static recrystallization occurs at the twin boundary and intersections,which weakens the deformation texture.

关键词： high Nb containing γ-TiAl alloy forging microstructure texture β phase

A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-xiao He Shang-Xu Wang gen-Yang Tang Chao Sun Hong-Bing li San-Yi Yuan Xian Wei li-Deng Gan xiao-Feng Dai Qiang Ge peng-peng Wei hui-Qing Zhang National Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research Institute of Petroleum Exploration and Development CNPCBeijing100083China Beijing Vocational College of Labour and Social Security Beijing100029China PetroChina Dagang Oilfield Exploration and Development Research Institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

Primary anaplastic lymphoma kinase-positive large B-cell lymphoma of the left bulbar conjunctiva: A case report

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World Journal of Clinical Cases 2024年第3期12卷 657-664页

作者： xiao-Hong Guo Chu-Bin li hui-hui Cao gen-Yuan Yang Department of Pathology Zhuhai People's Hospital(Zhuhai Hospital Affiliated with Jinan University)Zhuhai 519000Guangdong ProvinceChina Endoscopy Center Zhuhai People's Hospital(Zhuhai Hospital Affiliated with Jinan University)Zhuhai 519000Guangdong ProvinceChina

BACKGROUND Anaplastic lymphoma kinase(ALK)-positive large B-cell lymphoma(LBCL)is an aggressive and rare variant of diffuse ***,we report an uncommon case of stage IE extranodal ALK-positive LBCL initially originating in the bulbar *** SUMMARY A 63-year-old woman presented with a mass in the left bulbar conjunctiva that had persisted for six months,accompanied by swelling and pain that had per-sisted for 3 *** examination revealed an 8 mm slightly elevated pink mass in the lower conjunctival sac of the left ***,the tumor was com-posed of large immunoblastic and plasmablastic large lymphoid cells with scattered anaplastic or multinucleated large ***,the neoplastic cells were positive for ALK,CD10,CD138,Kappa,MUM1,BOB.1,OCT-2,CD4,CD45,EMA,CD79a,CD38,and AE1/AE3,and negative for CD20,PAX5,Lambda,BCL6,CD30 and all other T-cell *** results of gene rearrangement tests showed monoclonal IGH/IGK/IGL and TCRD *** in situ hybridization studies did not reveal any BCL2,BCL6 or MYC ***,Epstein-Barr virus was not detected by in situ hybridization in the *** on the histopathological and imaging examinations,the neoplasm was classified as stage IE ALK-positive *** further treatments were *** the 6,15,and 21 mo postoperative follow-up visits,the patient was in good condition,without obvious *** case represents the first example of primary extranodal ALK-positive LBCL presenting as a bulbar conjunctival mass,which is extremely rare and shares morphological and immunohistochemical features with a variety of other neo-plasms that can result in *** Awareness of the condition presented in this case report is necessary for early and accurate diagnosis and appropriate treatment.

关键词： Anaplastic lymphoma kinase Large B-cell lymphoma Conjunctiva Immunoglobulin/T-cell receptor gene Immunohistochemistry Case report

Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： peng-Cheng Wang ming-hui Chen Jim Jenkinson yong-Xin Song li Sun Department of Mechanical Engineering University of HoustonHoustonTX77024USA Guren Nanomaterials Suzhou215127JiangsuChina Department of Marine Engineering Dalian Maritime UniversityDalian116026LiaoningChina

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic *** practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and *** previous studies,the impact of friction forces on sealing performance is often *** work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing *** first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac *** we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after *** the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug *** addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial *** study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

Protective Effects of Danmu Extract Syrup on Acute Lung Injury Induced by lipopolysaccharide in Mice through Endothelial Barrier Repair

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Chinese Journal of Integrative Medicine 2024年第3期30卷 243-250页

作者： XU Han XU Si-cong li li-yan WU Yu-huang TAN Yin-feng CHEN Long liU pei liANG Chang-fu HE xiao-ning li yong-hui Hainan Provincial Key Lab of Research&Development on Tropic Herbs Hainan Medical UniversityHaikou571199China Department of Stomatology the Second Affiliated Hospital of Hainan Medical UniversityHaikou571199China

Objective:To investigate the effects of Danmu Extract Syrup(DMS) on lipopolysaccharide(LPS)-induced acute lung injury(Ali) in mice and explore the ***:Seventy-two male Balb/C mice were randomly divided into 6 groups according to a random number table(n=12),including control(normal saline),LPS(5 mg/kg),LPS+DMS 2.5 mL/kg,LPS+DMS 5 mL/kg,LPS+DMS 10 mL/kg,and LPS+Dexamethasone(DXM,5 mg/kg) *** pretreatment with DMS and DXM,the Ali mice model was induced by LPS,and the bronchoalveolar lavage fluid(BALF) were collected to determine protein concentration,cell counts and inflammatory *** lung tissues of mice were stained with hematoxylin-eosin,and the wet/dry weight ratio(W/D) of lung tissue was *** levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and IL-1βin BALF of mice were detected by enzyme linked immunosorbent *** expression levels of Claudin-5,vascular endothelial(VE)-cadherin,vascular endothelial growth factor(VEGF),phospho-protein kinase B(p-Akt) and Akt were detected by Western blot ***:DMS pre-treatment significantly ameliorated lung histopathological *** with the LPS group,the W/D ratio and protein contents in BALF were obviously reduced after DMS pretreatment(P1).The number of cells in BALF and myeloperoxidase(MPO) activity decreased significantly after DMS pretreatment(P1).DMS pre-treatment decreased the levels of TNF-α,IL-6 and IL-1β(P1).Meanwhile,DMS activated the phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) pathway and reversed the expressions of Claudin-5,VE-cadherin and VEGF(P1).Conclusions:DMS attenuated LPS-induced Ali in mice through repairing endothelial *** might be a potential therapeutic drug for LPS-induced lung injury.

关键词： Danmu Extract Syrup acute lung injury inflammatory factors vascular endothelial growth factor phosphoinositide 3-kinase/protein kinase B Chinese medicine Nauclea officinalis

Chemical derivatization strategies for enhancing the HPLC analytical performance of natural active triterpenoids

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Journal of Pharmaceutical Analysis 2024年第3期14卷 295-307页

作者： xiao-Feng Huang Ying Xue li yong Tian-Tian Wang pei Luo lin-Sen Qing Chengdu Institute of Biology Chinese Academy of SciencesChengdu610041China State Key Laboratory for Quality Research in Chinese Medicines Macao University of Science and TechnologyMacaoChina Sichuan Center for Disease Control and Prevention Chengdu610041China University of Chinese Academy of Sciences Beijing100049China

Triterpenoids widely exist in nature,displaying a variety of pharmacological *** triterpenoids in different matrices,especially in biological samples holds great ***-performance liquid chromatography(HPLC)has become the predominant method for triterpenoids analysis due to its exceptional analytical ***,due to the structural similarities among botanical samples,achieving effective separation of each triterpenoid proves challenging,necessitating significant improvements in analytical ***,triterpenoids are characterized by a lack of ultraviolet(UV)absorption groups and chromophores,along with low ionization efficiency in mass ***,routine HPLC analysis suffers from poor *** derivatization emerges as an indispensable technique in HPLC analysis to enhance its *** the structural characteristics of triterpenoids,various derivatization reagents such as acid chlorides,rhodamines,isocyanates,sulfonic esters,and amines have been employed for the derivatization analysis of *** review comprehensively summarized the research progress made in derivatization strategies for HPLC detection of ***,the limitations and challenges encountered in previous studies are discussed,and future research directions are proposed to develop more effective derivatization methods.

关键词： Triterpenoid HPLC Derivatization Quantification

Construction of daily precipitation series and the observational characteristics of extreme precipitation in Tianjin,China during 1888-2022

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Advances in Climate Change Research 2024年第1期15卷 52-61页

作者： peng SI Qing-Xiang li xiao-Yang CHEN min WANG Chuan-Jun LUO Tianjin Meteorological Information Center Tianjin Meteorological BureauTianjin 300074China Research Centerfor Ecology and Environment of Central Asia Chinese Academy of SciencesWulumuqi 830011China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 528478China Key Laboratory of Tropical Amosphere-Ocean System Ministry of EducationZhuhai 528478China Shaoguan Meteorological Service Shaoguan 512028China

Given the difficulties in rescuing and ensuring the quality of long-term climate data,current studies on century-scale climate change are usually limited to annual and monthly data,resulting in the poor detection of extreme climate events and their changes before *** this study,we reconstructed a daily precipitation series for Tianjin from 15 September 1887 to 31 December 2022 on the basis of the most comprehensive daily precipitation records collected from the Tianjin Meteorological Archive,China,and in reference to the precipitation analysis results based on the datasets developed by the Climatic Research Unit Time-Series version 4.06,Global Precipitation Climatology Centre and University of Delaware along with the application of various homogenisation methods for climate *** approach provides a complete and reliable century-long daily precipitation series for the study of regional or local extreme weather and climate *** reconstructed daily dataset reveals that the annual precipitation amount and R95 intensity in Tianjin during 1888-2022 lack significant trends and have values of 0.74±6.99 and-1.84±3.22 mm per decade,*** the annual and seasonal scales,the precipitation amount and R95 intensity,particularly those in autumn,have increased since the latter half of the 20th century relative to those in ***,the increase in precipitation amount and R95 intensity is relatively limited compared with that in atmospheric water vapour content due to surface warming,indicating the highly sensitive response of extreme precipitation events to *** addition,the estimates for the return periods of 5,10,20,50 and 100 years covering 1888-2022,1888-1950 and 1951-2022 depict that the intensity of heavy rain and above magnitude was highest in 1888-1950 and decreased in 1951-2022.

关键词： Over a century-long timescale Daily precipitation series Extreme precipitation Return period

Matrix metalloproteinase 2 degrades collagen I to regulate ovarian development by association with an insulin-like peptide

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Insect Science 2024年第4期31卷 1090-1106页

作者： Yi Wei xiao-lin Zhou peng Chen Tai-Hang liu Cheng Lu min-hui Pan State Key Laboratory of Silkworm genome Biology Southwest UniversityChongqingChina Key Laboratory for Sericulture Functional genomics and Biotechnology of Agricultural ministry Southwest UniversityChongqingChina Wenzhou Institute University of Chinese Academy of SciencesWenzhouZhejiang ProvinceChina

The ovary generally undergoes tissue remodeling during larval to pupal transition,which includes membrane degeneration and ovariole *** the same time,the hormones produced by insects significantly change during ***,the regulatory mechanism for ovarian development and hormones is not fully understood in ***,we found that matrix metalloproteinase 2(MMP2)was highly expressed in the ovarian capsules and ovarioles,and the development was abnormal after knocking out MMP2 in Bombyx *** process of abnormal degradation of collagen I due to MMP2 deletion,which resulted in abnormal development of ovarioles and eggs,was analyzed in *** proteomics of ovaries in the MMP2-knock out and wild type strains showed a critically significant difference in the expression of a protein,insulin-like peptide(ILP).Additional analysis revealed significant alteration of ILP during ovarian development,and abnormal expression of ILP significantly affected ovarian development in vivo and MMP2 expression in vitro and in *** results showed that MMP2 regulation of ovarian tissue remodeling is closely related to ILP *** study provides new insights into the regulatory mechanism of MMP2 and ovarian development in ***.

关键词： Bombyx mori collagen I insulin-like peptide matrix metalloproteinase ovarian development