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自适应正则化滤波化极方法研究

地球物理学报 2024年第3期67卷 1255-1272页

作者：何涛王皓张义蜜王万银 Colin G.Farquharson j.Kim Welford 长安大学地质工程与测绘学院西安710054 海洋油气勘探国家工程研究中心北京100028 中国科学院海洋地质与环境重点实验室山东青岛266071 Department of Earth Sciences Memorial University of NewfoundlandSt.John'sAlB 3X5Canada

化极是消除磁力异常斜磁化影响的关键步骤,可以在波数域(频率域)和空间域中实现.相比于空间域,在波数域(频率域)进行化极简单且高效,但在低纬度地区存在不稳定性问题,因此明确低纬度地区的范围,研究稳定、实用、精度高的低纬度地区化极... 详细信息

化极是消除磁力异常斜磁化影响的关键步骤,可以在波数域(频率域)和空间域中实现.相比于空间域,在波数域(频率域)进行化极简单且高效,但在低纬度地区存在不稳定性问题,因此明确低纬度地区的范围,研究稳定、实用、精度高的低纬度地区化极方法具有重要意义.本文通过理论研究得出化极因子振幅的最大值为2时,对应的磁化倾角的值为±45°,当磁化倾角在该范围内时,引起化极不稳定.因此采用正则化思想,提出了自适应正则化滤波化极方法(ARF-RTP),该方法利用化极因子振幅构建正则化滤波函数,并以振幅值等于2作为约束计算化极方法的参数值,从而实现自适应化极处理,提高了化极方法的稳定性及实用性.同时结合迭代算法提高了此方法的精度,有效地解决了低纬度地区化极的不稳定性问题.自适应正则化滤波这一思想不但可以解决化极的不稳定性问题,而且可以解决分量转换或者磁化方向转换的不稳定性问题以及类似数据处理中的不稳定性问题,具有广阔的推广应用前景.

关键词：化极低纬度地区振幅自适应正则化滤波迭代算法

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Neurological consequences of systemic inflammation in the premature neonate

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Neural Regeneration Research 2017年第6期12卷 890-896页

作者： Aparna Patra Hong Huang john A.Bauer Peter j.Giannone OMNI Academic Service Line and Division of Neonatology Department of Pediatrics Kentucky Children's Hospital College of MedicineUniversity of Kentucky

Despite substantial progress in neonatal care over the past two decades leading to improved survival of extremely premature infants, extreme prematurity continues to be associated with long term neurodevelopmental impairments. Cerebral white matter injury is the predominant form of insult in preterm brain leading to adverse neurological consequences. Such brain injury pattern and unfavorable neurologic sequelae is commonly encountered in premature infants exposed to systemic inflammatory states such as clinical or culture proven sepsis with or without evidence of meningitis, prolonged mechanical ventilation, bronchopulmonary dysplasia, necrotizing enterocolitis and chorioamnionitis. Underlying mechanisms may include cytokine mediated processes without direct entry of pathogens into the brain, developmental differences in immune response and complex neurovascular barrier system that play a critical role in regulating the cerebral response to various systemic inflammatory insults in premature infants. Understanding of these pathologic mechanisms and clinical correlates of such injury based on serum biomarkers or brain imaging findings on magnetic resonance imaging will pave way for future research and translational therapeutic opportunities for the developing brain.

关键词： premature consequences inflammation prematurity extremely translational dysplasia sepsis necrotizing neurological

Mitophagy in hepatocytes:Types,initiators and role in adaptive ethanol metabolism

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Liver Research 2018年第3期2卷 125-132页

作者： john j.Lemasters Zhi Zhong Department of Drug Discovery&Biomedical Sciences Medical University of South CarolinaCharlestonSCUSA Department of Biochemistry&Molecular Biology Medical University of South CarolinaCharlestonSCUSA

Mitophagy(mitochondrial autophagy)in hepatocytes is an essential quality control mechanism that removes for lysosomal digestion damaged,effete and superfluous *** has distinct *** type 1 mitophagy,typical of nutrient deprivation,cup-shaped sequestration membranes(phagophores)grow,surround and sequester individual mitochondria into mitophagosomes,often in coordination with mitochondrial *** sequestration,the outer compartment of the mitophagosome acidifies and the entrapped mitochondrion depolarizes,followed by fusion with *** contrast,mitochondrial depolarization stimulates type 2 mitophagy,which is characterized by coalescence of autophagic microtubule-associated protein 1A/1B-light chain 3(LC3)-containing structures on mitochondrial surfaces without the formation of a phagophore or mitochondrial *** to type 1 mitophagy,the inhibition of phosphoinositide-3-kinase(PI3K)does not block type 2 *** type 3 mitophagy,or micromitophagy,mitochondria-derived vesicles(MDVs)enriched in oxidized proteins bud off from mitochondrial inner and outer membranes and incorporate into multivesicular bodies by vesicle scission into the *** response to ethanol feeding,widespread ethanol-induced hepatocellular mitochondrial depolarization occurs to facilitate hepatic ethanol *** a consequence,type 2 mitophagy develops in response to the mitochondrial *** chronic high ethanol feeding,processing of depolarized mitochondria by mitophagy becomes compromised,leading to release of mitochondrial damage-associated molecular patterns(mtDAMPs)that promote inflammatory and profibrogenic *** propose that the persistence of mitochondrial responses for acute ethanol metabolism links initial adaptive ethanol metabolism to mitophagy and then to chronic maladaptive changes initiating onset and the progression of alcoholic liver disease(ALD).

关键词： Mitophagy Alcoholic liver disease(ALD) Ethanol Green fluorescent protein-light chain 3 (GFP-LC3) Hepatocytes Mitochondrial damage-associated molecular patterns(mtDAMPs)

A Damage-tolerant Bulk Metallic Glass at Liquid-nitrogen Temperature

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journal of Materials Science & Technology 2014年第6期30卷 627-630页

作者： jun Yi S.Mohsen Seifi Weihua Wang john j.Lewandowski Department of Materials Science and Engineering Case Western Reserve UniversityClevelandOH 44106-7204 USA Institute of Physics Chinese Academy of Sciences

Tensile tests and notch toughness tests were conducted on Zr61Ti2Cu25Al12 glass （ZT） at room temperature and liquid-nitrogen temperature. The tensile strength of ZT was improved from 1.63 GPa at room temperature to 1.72 GPa at liquid-nitrogen temperature. Micro-notches with a root radius of 1-3μm were introduced to test the notch toughness of ZT at room temperature and liquid-nitrogen temperature. The test results revealed that the notch toughness of ZT at liquid-nitrogen temperature is comparable to that of ZT at room temperature. The combination of high yield strength and notch toughness of ZT at liquid-nitrogen temperature is comparable to that of the best cryogenic engineering materials.

关键词： Metallic glasses Yield strength Fracture toughness Liquid-nitrogen temperature

Convergence Properties of Local Defect Correction Algorithm for the Boundary Element Method

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Computer Modeling in Engineering & Sciences 2019年第4期119卷 207-225页

作者： Godwin Kakuba john M.Mango Martijn j.H.Anthonissen Makerere University P.O.Box 7062KampalaUganda Eindhoven University of Technology P.O.Box 5135600 MB EindhovenThe Netherlands

Sometimes boundary value problems have isolated regions where the solution changes ***,when solving numerically,one needs a fine grid to capture the high *** fine grid can be implemented as a composite coarse-fine grid or as a global fine *** cheaper way of obtaining the composite grid solution is the use of the local defect correction *** technique is an algorithm that combines a global coarse grid solution and a local fine grid solution in an iterative way to estimate the solution on the corresponding composite *** algorithm is relatively new and its convergence properties have not been studied for the boundary element *** this paper the objective is to determine convergence properties of the algorithm for the boundary element ***,we formulate the algorithm as a fixed point iterative scheme,which has also not been done before for the boundary element method,and then study the properties of the iteration *** show that we can always expect ***,the algorithm opens up a real alternative for application in the boundary element method for problems with localised regions of high activity.

关键词： Local defect defect correction composite grids integral equation methods boundary elements

Vibration induced flow in hoppers:DEM 2D polygon model

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Particuology 2008年第6期6卷 455-466页

作者： Feras Y. Fraige Paul A. Langston Andrew j. Matchett john Dodds Faculty of Mining and Environmental Engineering Al-Hussein Bin Talal University Jordan Chemical and Environmental Engineering Nottingham University University Park Chemical Engineering University of Teesside Centre RAPSODEE Ecole Des Mines

A two-dimensional discrete element model （DEM） simulation of cohesive polygonal particles has been developed to assess the benefit of point source vibration to induce flow in wedge-shaped hoppers. The particle-particle interaction model used is based on a multi-contact principle. The first part of the study investigated particle discharge under gravity without vibration to determine the critical orifice size （Bc） to just sustain flow as a function of particle shape. It is shown that polygonal-shaped particles need a larger orifice than circular particles. It is also shown that Bc decreases as the number of particle vertices increases. Addition of circular particles promotes flow of polygons in a linear manner. The second part of the study showed that vibration could enhance flow, effectively reducing Bc. The model demonstrated the importance of vibrator location （height）, consistent with previous continuum model results, and vibration amplitude in enhancing flow.

关键词： Bulk solids Vibration DEM Hoppers Materials handling Polygon

SPECIAL ISSUE EDITORIAL ON ADVANCES IN COLLABORATIVE SYSTEMS ENGINEERING FOR PRODUCT DESIGN, PRODUCTION AND SERVICE NETWORK

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journal of Systems Science and Systems Engineering 2016年第2期25卷 139-141页

作者： Amy j.C. Trappey Weiming Shen john jianzhong Cha Department of Industrial Engineering and Engineering Management National Tsing Hua University Taiwan China Integrated Manufacturing Technologies Institute National Research Council Canada Canada Department of Mechanical Engineering Beijing Jiaotong University China

From the perspectives of engineering （CE）, computer concurrent supported cooperative work （CSCW）, product lifecycle management （PLM）, to collaborative supply chain and service network, collaborative systems engineering （CSE） has been extended and enriched in many research efforts. CSE is not just a technique or method but also a fundamental business philosophy and strategy.

关键词： perspectives concurrent engineering

Annealing Response of Cold-Rolled Vanadium Microalloyed Sheet Steels

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journal of Iron and Steel Research International 2011年第S1期18卷 404-411页

作者： john G Speer David K Matlock Robert j Glodowski A dvanced Steel Processing and Products Research Center Colorado School of MinesGoldenColorado USA East Metals (North America) LLCPittsburghPAUSA

Vanadium microalloying is widely employed in hot-rolled HSLA products;because of its relatively high solubility in austenite,vanadium plays a special role in thin-slab cast hot-rolled products where reheating is limited prior to *** cold-rolled and annealed sheet steels,vanadium technology has been employed in bake-hardenable drawing-quality steels,and in HSLA *** studies have investigated the continuous and batch annealing response of vanadium-containing cold-rolled HSLA steels,with an emphasis on aluminum and nitrogen variations (because of the special importance of nitrogen in vanadium microallyed steels,and interesting interactions between vanadium,aluminum and nitrogen).The present contribution reviews some key aspects of vanadium-microalloyed coldrolled sheet steels,and highlights the results of selected studies showing the influence of steel composition and processing.

关键词： Microalloying vanadium,bake-hardening cold rolled sheet steel

Immune checkpoint inhibitor-mediated colitis in gastrointestinal malignancies and inflammatory bowel disease

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World journal of Gastrointestinal Oncology 2021年第8期13卷 772-798页

作者： Alexa R Weingarden Samuel j S Rubin john Gubatan Division of Gastroenterology and Hepatology Department of MedicineStanford UniversityRedwood CityCA 94063United States Stanford University School of Medicine Stanford UniversityRedwood CityCA 94063United States

Immune checkpoint inhibitors(ICI)have markedly changed the landscape of cancer *** re-invigorating the immune system against tumors,ICI provide novel therapeutic options for a broad variety of malignancies,including many gastrointestinal(GI)***,these therapies can also induce autoimmune-like side effects in healthy tissue across the *** of the most common of these side effects is ICI-mediated colitis and diarrhea(IMC).Here,we review the incidence and risk of IMC in ICI therapy,with a focus on what is known regarding IMC in patients with GI *** also discuss data available on the use of ICI and risk of IMC in patients with pre-existing inflammatory bowel disease,as these patients may have increased risk of IMC due to their underlying intestinal pathology.

关键词： Immune checkpoint inhibitors Cytotoxic T-lymphocyte antigen 4 Programmed cell death protein-1 Inflammatory bowel disease Gastrointestinal cancer