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Modeling multilook polarimetric SAR images with heavy-tailed rayleigh distribution and novel estimation based on matrix log-cumulants

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Science China(Information Sciences) 2013年第6期56卷 60-73页

作者： LIU tao CUI HaoGui mao tao XI ZeMin GAO Jun Electronic School of Engineering Naval University of Engineering Fourth Department Headquarters of Navy

With the improvements in modern radar resolution,the Gaussian-fluctuation model based on the central limit theorem does not accurately describe the scattering echo from *** contrast,the heavytailed Rayleigh distribution,based on the generalized central limit theorem,performs well in modeling the synthetic aperture radar(SAR) images,whereas its application to multi-look image processing is *** describe successful modeling of multilook polarimetric SAR images with the heavy-tailed Rayleigh distribution and present novel parameter estimators based on matrix log-cumulants for the heavy-tailed Rayleigh distribution including the equivalent number of looks(ENL).First,a compound variable of heavy-tailed Rayleigh distribution is divided into a product of a positive alpha-stable variable and a complex Gaussian *** parameter estimations of the characteristic exponent and scale parameter based on log-cumulants in a single polarization channel are then ***,the matrix log-cumulants(MLCs) for full polarization in multilook images are obtained,which can be applied to estimate model ***,a novel ENL estimator based on MLC is presented that describes the model more *** to all other multivariable product models,this estimator performs better than existing ***,calculations on both simulated and real data are performed that give good fits with theoretical *** processing in one image with a fixed pixel number can improve parameter estimations over single-look *** heavy-tailed Rayleigh model with its parameter estimation provides a new method to analyze the multilook polarimetric SAR images for target detection and classification.

关键词： heavy-tailed Rayleigh distribution multilook polarimetric synthetic aperture radar mellin transform matrix log-cumulants

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Chemical composition and structural identification of primary carbides in as-cast H13 steel

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International Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 839-848页

作者： Ming-tao mao Han-jie Guo Fei Wang Xiao-lin Sun School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083 China Central Iron & Steel Research Institute Beijing 100081 China

The aim of this study was to characterize the primary carbides formed in as-cast H13 steel. The composition, morphology, type, and size of primary carbides in as-cast H13 steel were investigated by optical microscope (OM), field emission scanning electron microscopy (FE-SEM), electron back-scattered diffraction (EBSD), and X-ray diffraction (XRD) analysis. The number of primary carbides was investigated by ASPEX automated inclusion analysis system. The results indicated that primary carbides in as-cast H13 steel are mainly composed of Cr, Mo, V, and Ti, and there exist four kinds of primary carbides in the interdendritic zones of H13 steel, which are stripy Mo–Cr-rich M2C, eutectic Mo–Cr-rich M2C, V-rich MC, and V-rich MC with Ti and N. Thermodynamic calculation indicated that M2C precipitates in liquid phase at solid fractions larger than 0.99, while MC precipitates in liquid phase at solid fractions larger than 0.96. Statistical results indicated that the number of M2C is much greater than the number of other kinds of primary carbides. Most primary carbides are blocky, with lengths of no more than 10 μm and a length/width ratio of no more than 3. The large primary carbides in as-cast H13 steel are mainly M2C.

关键词： primary carbide phase identification H13 steel precipitation thermodynamic

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Investigation of scale inhibition mechanisms based on the effect of scale inhibitor on calcium carbonate crystal forms

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Science China Chemistry 2007年第1期50卷 114-120页

作者： ZHANG GuiCai GE JiJiang SUN MingQin PAN BinLin mao tao SONG ZhaoZheng College of Petroleum Engineering University of PetroleumDongying 257061China College of Chemical Engineering University of PetroleumBeijing 102200China

To probe the scale inhibition mechanisms,calcium carbonate scale occurring before and after the ad- dition of scale inhibitors was *** results from scale SEM confirm that,without scale inhibitor, calcium carbonate scale shows rhombohedron and hexagon,which are the characteristic feathers of *** addition of inhibitors,morphology of scale is changed,and the more efficient the scale inhibitor is,the more greatly the morphology is *** elucidate the scale constitute,they were further analyzed by FT-IR,*** calcite,vaterite and aragonite occur in calcium carbonate scale after addition of inhibitors,and the higher scale inhibition efficiency is,the more vaterite presents in *** can be concluded that the alteration of morphology is ascribed to the change of crystal form. There are three stages in the crystallizing process including occurrence and disappearing of unstable phase,occurrence and disappearing of metastable phase,development of stable *** scale inhibitors,metastable phases usually transform into stable phase,thus the main constitute of formed scale is *** scale inhibitors are added,both formation and transformation of metastable phases are inhibited,which results in the occurrence of aragonite and *** the fact that more vaterite presents in scale with a more efficient scale inhibitor added,we can see that the function of scale inhibitor is realized mainly by controlling the crystallizing process at the second stage.

关键词： calcium carbonate scale scale inhibitor mechanism of scale inhibiting calcite aragonite vaterite

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Gamma-aminobutyric acid A receptor gamma 2 subunit following Mg-free-induced seizures in cultured developing neurons

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Neural Regeneration Research 2008年第11期3卷 1187-1191页

作者： Jian Li Dingan mao tao Bo Xingfang Li Lu Yi Zhuwen Yi Department of Pediatrics Second Xiangya Hospital Central Southem University Changsha 410011 Hunan Province China

BACKGROUND： Studies have demonstrated that in vitro cultured cortical neurons from embryonic rats can produce spontaneous recurrent epileptiform discharges following transient Mg^2＋-free extracellular solution culture. OBJECTIVE： To explore gammaminobutyric acid A receptor （GABAAR）γ 2 subunit expression following Mg^2＋-free-induced seizures in cultured developing neurons. DESIGN, TIME AND SETTING： Cellular and molecular biology. The in vitro experiment was performed at the Department of Pediatrics, Second Xiangya Hospital of Central Southern University between January 2007 and February 2008. MATERIALS： Cortical neurons of Wistar rats on gestational days 16-17 were used. Normal extracellular solution （pH 7.3） consisted of NaCl 145 mmol/L, KCl 2.5 mmol/L, HEPES l0 mmol/L, MgC12 1 mmol/L, CaC12 2 mmol/L, glucose 10 mmol/L, and glycine 0.01 mmol/L. In addition, there was no MgCl2 in the Mg^2＋-free extracellular solution. METHODS： Cortical neurons cultured for 6 days were exposed to normal extracellular solution （control group） and Mg^2＋-free media （Mg^2＋-free group） respectively for 3 hours, followed by continuous culture in DMEM solution. MAIN OUTCOME MEASURES： On days 1, 7 and 12 after Mg^2＋-free treatment, real-time RT-PCR, immunochemistry, and flow cytometry were used to detect GABAAR 3/2 subunit expression. RESULTS： Compared with the control group, GABAAR γ-positive cells decreased significantly on days 1 and 7 after Mg^2＋-free treatment （P 〈 0.01）, but significantly increased on day 12 （P 〈 0.01 ）. GABAAR γ2 subunit mRNA expression decreased significantly at 7 days Mg^2＋-free treatment when measured by real-time RT-PCR compared with the control group （P 〈 0.05）. CONCLUSION： GABAAR γ2 subunit expression is modified following Mg-free-induced seizures in cultured developing neurons. This indicates the possibility that abnormal GABAA receptor expression might play an important role in development of neuronal injury.

关键词： seizures gamma-aminobutyfic acid A receptor γ2 subunit neuron development

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Quantum Statistical Properties of Binomial Field Interacting with Two Entangled Atoms

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Communications in Theoretical Physics 2008年第10期50卷 971-973页

作者： JIAO Zhi-Yong MA Jun-mao SHANG Yong-tao LI Ning FU Xia College of Physical Science and Technology China University of Petroleum （East China） Dongying 257061 China

Quantum statistical properties of the binomial field interacting with the two entangled atoms are investi-gated for the different initial *** is found that the sub-Poissonian distribution and the antibunching effect c... 详细信息

关键词： sub-Poissonian distribution antibunching effect binomial field Bell state

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Effects of Mg Addition on Inclusions Formation and Resultant Solidification Structure Changes of Ti-stabilized Ultra-pure Ferritic Stainless Steel

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Journal of Iron and Steel Research International 2014年第6期21卷 583-588页

作者： Ying-tie XU Zhao-ping CHEN mao-tao GONG Da SHU Yue-mei TIAN Xiang-qian YUAN Research Institute Baoshan Iron and Steel Co.Ltd. State Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong University

The effects of Mg addition on the formation of nonmetallic inclusions and solidification structure of Ti-sta- bilized ultra-pure ferritie stainless steels were investigated by experimentally casting ingots with different composi tions. Thermodynamic analyses on the formation of complex inclusions after adding Mg into steels were carried out combined with the scanning electron microscopy energy dispersive spectrometry （SEM EDS） analysis. And the EDS analysis showed that in steel samples with Mg addition, a new spinel crystal phase combined with AI2O3- TiOx formed. It was also found that after Mg addition, the proportions of equiaxed grain zone of 409L, 4003, 439 and 443NT steels increased from 10.2%, 21.8%, 13.4% and 18.6% to 84.3%, 92.3%, 91.1% and 100.0%, respec tively. Since the planar disregistry between spinel and TiN is 5. 1%0, spinel could promote the precipitation of TiN and increase the number density of TiN inclusions in steel melts. The mechanism of solidification structure refinement after adding Mg into steels supposed that the complex inclusions of spinel and TiN in high number density enhanced columnar-to-equiaxed transition, since the planer disregistry between δ phase and spinel is 1.4 %.

关键词： ferritic stainless steel Mg additionl inclusion TiN solidification structurel disregistry

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Glutamine addiction and therapeutic strategies in pancreatic cancer

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World Journal of Gastrointestinal Oncology 2023年第11期15卷 1852-1863页

作者： Lin-Lin Ren tao mao Pin Meng Li Zhang Hong-Yun Wei Zi-Bin Tian Department of Gastroenterology The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina Department of Pathology The Affiliated Hospital of Qingdao UniversityQingdao 266000China

Pancreatic cancer remains one of the most lethal diseases worldwide owing to its late diagnosis,early metastasis,and poor *** current therapeutic options are limited,there is an urgent need to investigate novel targeted treatment *** cancer faces significant metabolic challenges,principally hypoxia and nutrient deprivation,due to specific microenvironmental constraints,including an extensive desmoplastic stromal *** cancer cells have been shown to rewire their metabolism and energy production networks to support rapid survival and *** glucose uptake and glycolytic pathway activity during this process have been extensively ***,growing evidence suggests that pancreatic cancer cells are glutamine *** a nitrogen source,glutamine directly(or indirectly via glutamate conversion)contributes to many anabolic processes in pancreatic cancer,including amino acids,nucleobases,and hexosamine *** also plays an important role in redox homeostasis,and when converted toα-ketoglutarate,glutamine serves as an energy and anaplerotic carbon source,replenishing the tricarboxylic acid cycle *** present study aims to provide a comprehensive overview of glutamine metabolic reprogramming in pancreatic cancer,focusing on potential therapeutic approaches targeting glutamine metabolism in pancreatic cancer.

关键词： Pancreatic cancer Glutamine metabolism Cancer treatment Therapeutic strategies

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Study of the ionospheric anomaly before the Wenchuan earthquake

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Chinese Science Bulletin 2009年第4期54卷 1080-1086页

作者： YU tao mao Tian WANG YunGang WANG JingSong Nation Center for Space Weather China Meteroligical Administration Beijing 100081 China

The behavior of the ionosphere before the Wenchuan earthquake is analyzed with the global TEC and ionospheric foF2 observed at Xiamen. It can be found from TEC maps that in the afternoon (16―18LT) on May 9, 2008, 3 days before the earthquake, there is an enhancement of TEC with an amplitude of 10―15 TECU appearing in the east-south direction of Wenchuan, and another enhancement appears at the conjugate region of the Southern Hemisphere with an amplitude of 10 TECU, but no obvious in-crement or decrement can be seen in other regions on global scale. It can also be found that on May 6 (6 days before the great earthquake), there is a decrement of TEC with small amplitude of 4TECU and larger area with 80° along the longitude in southern China, and there is no synchronous decrement observed at the conjugate region of the Southern Hemisphere. There are also many anomalies ob-served by ionosondes across China. The result shows that foF2 and TEC abnormally increased, which is different from pervious results that ionospheric parameters decreased prior to earthquakes. Pre-liminary results suggest that the enhancement on May 9 maybe has a close relationship with the pos-sible enhancement of ionospheric electric fields, and it may be an ionospheric precursor of earth-quakes. Whereas the decrement on May 6 may be attributed to the geomagnetic disturbance appearing on May 5.

关键词：电离层异常地震前汶川电离层参数地球电离层地磁场扰动华南地区 TEC

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PROGRESSIVE GRAPHIC SIMPLIFICATION OF CONTOURS BASED ON SPATIAL REASONING

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Geo-spatial Information Science 2000年第4期3卷 67-72页

作者： GUO Qingsheng WANG tao mao Jianhua WU Hehai [FK(W12。32ZQ] School of Land Science Wuhan China

This paper discusses the rules representing relief with contour lines and methods for automatically constructing relation of contour ***,the improvement of existent methods for extracting the topographic characteristic points and lines is *** the basis of this analysis,we propose a series of practicable progressive graphic simplification ideas of contour lines and concrete algorithms for the exception’s *** this way,graphic generalizations of contour lines at different scales are integrated into one model that is convenient to implement,and in which contour lines’ intersection in generalization can be controlled.

关键词： contour line graphic simplification topographic terrain feature progressive cartographic generalization

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Gastric pyloric gland adenoma resembling a submucosal tumor:A case report

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World Journal of Clinical Cases 2020年第11期8卷 2380-2386页

作者： Cong-Cong Min Jun Wu Feng Hou tao mao Xiao-Yu Li Xue-Li Ding Hua Liu Department of Gastroenterology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina Department of Pathology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina

BACKGROUND Pyloric gland adenoma(PGA)is a recently described and rare *** tumor(SMT)-like PGA is more difficult to diagnose and differentiate from other submucosal *** SUMMARY We present the case of a 69-year-old man with a 10 mm SMT-like elevated lesion with an opening in the upper part of the gastric body,referred to our hospital for further endoscopic *** endoscopy with narrow-band imaging,endoscopic ultrasonography,and complete endoscopic submucosal dissection were performed on the *** findings revealed tightly packed tubular glands lined with cuboidal or columnar cells that had round-tooval nuclei containing occasional prominent nucleoli and an eosinophilic cytoplasm similar to that in non-neoplastic gastric pyloric ***,immunohistochemical analysis showed positive staining for both mucin 5AC and mucin ***,we arrived at the final diagnosis of gastric *** there was no apparent malignant component in this tumor,PGA has been considered a precancerous disease with a high risk of transformation into *** PGA should be considered when detecting gastric SMT-like *** and pathologists should focus on PGA due to its malignant potential.

关键词： Pyloric gland adenoma Submucosal tumor Endoscopic submucosal dissection Case report

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