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Assessment and Visualization of Ki67 Heterogeneity in Breast Cancers through Digital Image Analysis
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作者 Chien-Hui Wu Min-Hsiang Chang +1 位作者 Hsin-Hsiu Tsai Yi-Ting Peng 《Advances in Breast Cancer Research》 CAS 2024年第2期11-26,共16页
The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki... The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki67 heterogeneity and distribution patterns in breast carcinoma. Using Smart Pathology software, we digitized and analyzed 42 excised breast carcinoma Ki67 slides. Boxplots, histograms, and heat maps were generated to illustrate the KI distribution. We found that 30% of cases (13/42) exhibited discrepancies between global and hotspot KI when using a 14% KI threshold for classification. Patients with higher global or hotspot KI values displayed greater heterogenicity. Ki67 distribution patterns were categorized as randomly distributed (52%, 22/42), peripheral (43%, 18/42), and centered (5%, 2/42). Our sampling simulator indicated analyzing more than 10 high-power fields was typically required to accurately estimate global KI, with sampling size being correlated with heterogeneity. In conclusion, using digital image analysis in whole-slide images allows for comprehensive Ki67 profile assessment, shedding light on heterogeneity and distribution patterns. This spatial information can facilitate KI surveys of breast cancer and other malignancies. 展开更多
关键词 Ki67 Heterogeneity Breast Cancer Digital Image analysis
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Single-element Anomaly Mapping from Stream Sediment Geochemical Landscapes Aided by Digital Terrain Analysis
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作者 XIANG Jie XIA Peng +2 位作者 XIAO Keyan Emmanuel John M.CARRANZA CHEN Jianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期149-162,共14页
The identification of anomalies within stream sediment geochemical data is one of the fastest developing areas in mineral exploration.The various means used to achieve this objective make use of either continuous or d... The identification of anomalies within stream sediment geochemical data is one of the fastest developing areas in mineral exploration.The various means used to achieve this objective make use of either continuous or discrete field models of stream sediment geochemical data.To map anomalies in a discrete field model of such data,two corrections are required:background correction and downstream dilution correction.Topography and geomorphology are important factors in variations of element content in stream sediments.However,few studies have considered,through the use of digital terrain analysis,the influence of geomorphic features in downstream dilution correction of stream sediment geochemical data.This study proposes and demonstrates an improvement to the traditional downstream dilution correction equation,based on the use of digital terrain analysis to map single-element anomalies in stream sediment geochemical landscapes.Moreover,this study compares the results of analyses using discrete and continuous field models of stream sediment geochemical data from the Xincang area,Tibet.The efficiency of the proposed methodology was validated against known mineral occurrences.The results indicate that catchment-based analysis outperforms interpolation-based analysis of stream sediment geochemical data for anomaly mapping.Meanwhile,the proposed modified downstream dilution correction equation proved more effective than the original equation.However,further testing of this modified downstream dilution correction is needed in other areas,in order to investigate its efficiency further. 展开更多
关键词 stream sediment sample catchment basin digital terrain analysis downstream dilution correction background correction
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Investigation of pore geometry influence on fluid flow in heterogeneous porous media:A pore-scale study 被引量:1
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作者 Ramin Soltanmohammadi Shohreh Iraji +3 位作者 Tales Rodrigues de Almeida Mateus Basso Eddy Ruidiaz Munoz Alexandre Campane Vidal 《Energy Geoscience》 EI 2024年第1期72-88,共17页
Brazilian pre-salt reservoirs are renowned for their intricate pore networks and vuggy nature,posing significant challenges in modeling and simulating fluid flow within these carbonate reservoirs.Despite possessing ex... Brazilian pre-salt reservoirs are renowned for their intricate pore networks and vuggy nature,posing significant challenges in modeling and simulating fluid flow within these carbonate reservoirs.Despite possessing excellent petrophysical properties,such as high porosity and permeability,these reservoirs typically exhibit a notably low recovery factor,sometimes falling below 10%.Previous research has indicated that various enhanced oil recovery(EOR)methods,such as water alternating gas(WAG),can substantially augment the recovery factor in pre-salt reservoirs,resulting in improvements of up to 20%.Nevertheless,the fluid flow mechanism within Brazilian carbonate reservoirs,characterized by complex pore geometry,remains unclear.Our study examines the behavior of fluid flow in a similar heterogeneous porous material,utilizing a plug sample obtained from a vugular segment of a Brazilian stromatolite outcrop,known to share analogies with certain pre-salt reservoirs.We conducted single-phase and multi-phase core flooding experiments,complemented by medical-CT scanning,to generate flow streamlines and evaluate the efficiency of water flooding.Subsequently,micro-CT scanning of the core sample was performed,and two cross-sections from horizontal and vertical plates were constructed.These cross-sections were then employed as geometries in a numerical simulator,enabling us to investigate the impact of pore geometry on fluid flow.Analysis of the pore-scale modeling and experimental data unveiled that the presence of dead-end pores and vugs results in a significant portion of the fluid remaining stagnant within these regions.Consequently,the injected fluid exhibits channeling-like behavior,leading to rapid breakthrough and low areal swept efficiency.Additionally,the numerical simulation results demonstrated that,irrespective of the size of the dead-end regions,the pressure variation within the dead-end vugs and pores is negligible.Despite the stromatolite's favorable petrophysical properties,including relatively high porosity and permeability,as well as the presence of interconnected large vugs,the recovery factor during water flooding remained low due to early breakthrough.These findings align with field data obtained from pre-salt reservoirs,providing an explanation for the observed low recovery factor during water flooding in such reservoirs. 展开更多
关键词 Pore-scale modeling Pore geometry Flow streamlines Computational modeling Digital rock analysis
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Changes in filtration and capacitance properties of highly porous reservoir in underground gas storage:CT-based and geomechanical modeling
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作者 Valerii Khimulia Vladimir Karev +1 位作者 Yury Kovalenko Svyatoslav Barkov 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2982-2995,共14页
The paper presents the results of comprehensive studies of filtration and capacitance properties of highly porous reservoir rocks of the aquifer of an underground gas storage facility.The geomechanical part of the res... The paper presents the results of comprehensive studies of filtration and capacitance properties of highly porous reservoir rocks of the aquifer of an underground gas storage facility.The geomechanical part of the research included studying the dependence of rock permeability on the stress-strain state in the vicinity of the wells,and physical modeling of the implementation of the method of increasing the permeability of the wellbore zone-the method of directional unloading of the reservoir.The digital part of the research included computed tomography(CT)-based computer analysis of the internal structure,pore space characteristics,and filtration properties before and after the tests.According to the results of physical modeling of deformation and filtration processes,it is found that the permeability of rocks before fracture depends on the stress-strain state insignificantly,and this influence is reversible.However,when downhole pressure reaches 7-8 MPa,macrocracks in the rock begin to grow,accompanied by irreversible permeability increase.Porosity,geodesic tortuosity and permeability values were obtained based on digital studies and numerical modeling.A weak degree of transversal anisotropy of the filtration properties of rocks was detected.Based on the analysis of pore size distribution,pressure field and flow velocities,high homogeneity and connectivity of the rock pore space is shown.The absence of pronounced changes in pore space characteristics and pore permeability after non-uniform triaxial loading rocks was shown.On the basis of geometrical analysis of pore space,the reasons for weak permeability anisotropy were identified.The filtration-capacitance properties obtained from the digital analysis showed very good agreement with the results of field and laboratory measurements.The physical modeling has confirmed the efficiency of application of the directional unloading method for the reservoir under study.The necessary parameters of its application were calculated:bottomhole geometry,stage of operation,stresses and pressure drawdown value. 展开更多
关键词 Permeability anisotropy Reservoir porosity Rocks computed tomography(CT) Digital core analysis Filtration flow numerical modeling
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Stability analysis unit and spatial distribution pattern of the terrain texture in the northern Shaanxi Loess Plateau 被引量:4
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作者 DING Hu NA Jia-ming +2 位作者 HUANG Xiao-li TANG Guo-an LIU Kai 《Journal of Mountain Science》 SCIE CSCD 2018年第3期577-589,共13页
Terrain texture analysis is an important method of digital terrain analysis in quantitative geomorphological research and in the exploration of the spatial heterogeneity and autocorrelation of terrain features. Howeve... Terrain texture analysis is an important method of digital terrain analysis in quantitative geomorphological research and in the exploration of the spatial heterogeneity and autocorrelation of terrain features. However, a major issue often neglected in previous studies is the calculation unit of the terrain texture, that is, the stability analysis unit. As the test size increases, the derived terrain textures become increasingly similar so that their differences can be ignored. The test size of terrain texture is defined as the stability analysis unit. This study randomly selected 48 areas within the Loess Plateau in northern Shaanxi in China as the study sites and used the gray level co-occurrence matrix to calculate the terrain texture. The stability analysis unit of the terrain texture was then extracted, and its spatial distribution pattern in the Loess Plateau was studiedusing spatial interpolation method. Four terrain texture metrics, i.e., homogeneity, energy, correlation, and contrast, were extracted on the basis of the stability analysis unit, and the spatial variation patterns of these parameters were studied. Results showed that the spatial distribution pattern and the terrain texture metrics reflected a trend of high–low–high from north to south, which correlated with the spatial distribution of the landforms at the Loess Plateau. In addition, the terrain texture measures was significantly correlated with the terrain factors of gully density and slope, and this relationship showed that terrain texture measures based on the stability analysis unit could reflect the basic characteristics of terrain morphology. The stability analysis unit provided a reasonable analytical scale for terrain texture analysis and could be used as a measure of the regional topography to accurately describe basic terrain characteristics. 展开更多
关键词 Digital terrain analysis Terrain texture Stability analysis unit Spatial distribution Loess Plateau
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Collagen proportionate area of liver tissue determined by digital image analysis in patients with HBV-related decompensated cirrhosis 被引量:1
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作者 Shi-Bin Xie, Chao Ma, Chao-Shuang Lin,Ying Zhang, Jian-Yun Zhu and Wei-Min Ke Department of Infectious Disease, Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510630, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2011年第5期497-501,共5页
BACKGROUND: The accurate assessment of the degree of hepatic fibrosis plays a critical role in guiding the diagnosis, treatment and prognostic assessment of chronic liver diseases. Liver biopsy is currently the most r... BACKGROUND: The accurate assessment of the degree of hepatic fibrosis plays a critical role in guiding the diagnosis, treatment and prognostic assessment of chronic liver diseases. Liver biopsy is currently the most reliable method to evaluate the severity of hepatic fibrosis. However, liver biopsy is an invasive procedure associated with morbidity and mortality, and has several limitations in patients with decompensated cirrhosis. There is no report on the collagen proportionate area (CPA) of liver tissue in the decompensated stage of cirrhosis. This study aimed to determine the CPA of resected liver tissue samples from patients with HBV-related decompensated cirrhosis using digital image analysis, and to analyze the relationship between the CPA and liver functional reserve. METHODS: Fifty-three resected liver tissue samples from liver transplant patients with chronic hepatitis B-induced decompensated cirrhosis were stained with Masson’s trichrome, and the CPA in these samples was quantitatively determined using digital image analysis. The values of relevant liver function just before liver transplantation, the CPA in liver tissue, and their correlation were analyzed. RESULTS: The mean CPA at the decompensated stage of cirrhosis was 35.93±14.42% (11.24%-63.41%). The correlation coefficients of the CPA with a model for end-stage liver disease score, serum total bilirubin and international standard ratio of prothrombin B were 0.553, 0.519 and 0.533, respectively (P<0.001). With increasing CPA values, the three indices reflecting liver functional reserve also changed significantly.CONCLUSIONS: The degree of fibrosis may be correlated with the functional reserve. With the advancement of fibrosis, the liver functional reserve is attenuated accordingly. 展开更多
关键词 collagen proportionate area digital image analysis decompensated cirrhosis chronic hepatitis B
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DIGITAL IMAGE ANALYSIS OF PHASE STRUCTURE IN THE BLEND OF POLY(BUTYLENE TEREPHTHALATE-COCAPROLACTONE) WITH POLYCARBONATE
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作者 马德柱 贺丽玲 +3 位作者 邹应芳 罗筱烈 Takafumi Hayashi Toshio Nishi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第1期44-48,共5页
The digital image processing technique was used for the extraction of physical information from the temporal image of phase structure in the process of phase separation in the blend of poly (butylene terephthalate-co-... The digital image processing technique was used for the extraction of physical information from the temporal image of phase structure in the process of phase separation in the blend of poly (butylene terephthalate-co-caprolactone )with polycarbonate. The power spectrum images of the two-dimensional Fourier transformation (2DFT) of the temporal image of phase structure reflect the change of the phase size with time. 展开更多
关键词 Digital image analysis Phase structure Fourier transformation Wave vector BCL copolymer
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Development of the HL-2M digital pulse analysis system
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作者 Yinhai PAN Bowen ZHENG +1 位作者 Wei ZHANG Zejie YIN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第11期93-98,共6页
A digital pulse analysis system is an important diagnostic system in nuclear physics experimental research.In response to the demand for reflecting the particle state in a nuclear physics experiment,we have designed a... A digital pulse analysis system is an important diagnostic system in nuclear physics experimental research.In response to the demand for reflecting the particle state in a nuclear physics experiment,we have designed and developed a real-time digital pulse analysis system and applied it to the digital nuclear pulse waveform discrimination of different detectors in the HL-2M tokamak.The system is based on the peripheral component interconnect extensions for instrumentation(PXI)platform,while its software was written in LABVIEW.The key technologies involved in the system implementation include digital pulse analysis technology,digital discrimination technology,pulse height analysis technology,etc.The system has been applied to the plastic scintillator detector at the Neutron Source Lab of the University of Science and Technology of China.And the experimental results indicate that the system can discriminate between neutron(n)particles and gamma(γ)particles well when used to measure the plastic scintillator detector. 展开更多
关键词 digital pulse analysis plastic scintillator detector digital discrimination pulse height analyses
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Experimental analysis on the nonlinear behavior of DC barrier discharge plasmas
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作者 Dogan MANSUROGLU Ilker Umit UZUN-KAYMAK 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第1期44-50,共7页
Nonlinear behavior of glow discharge plasmas is experimentally investigated.The glow is generated between a barrier semiconductor electrode,Chromium doped namely Gallium Arsenide(Ga As:Cr),as a cathode and an Indiu... Nonlinear behavior of glow discharge plasmas is experimentally investigated.The glow is generated between a barrier semiconductor electrode,Chromium doped namely Gallium Arsenide(Ga As:Cr),as a cathode and an Indium–Tin Oxide(ITO) coated glass electrode as an anode,in reverse bias.The planar nature of electrodes provides symmetry in spatial geometry.The discharge behaves oscillatory in the time domain,with single and sometimes multiperiodicities in plasma current and voltage characteristics.In this paper,harmonic frequency generation and transition to chaotic behavior is investigated.The observed current–voltage characteristics of the discharge are discussed in detail. 展开更多
关键词 DC glow discharges nonlinear behavior digital signal analysis
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Analysis of Shoreline Changes in Ikoli River in Niger Delta Region Yenagoa,Bayelsa State Using Digital Shoreline Analysis System(DSAS)
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作者 Egai Ayibawari Obiene Eteh Desmond Rowland Inko-Tariah Ibiso Michael 《Journal of Marine Science》 2022年第1期34-42,共9页
The use of Digital Shoreline Analysis System was used to determine shoreline changes in Ikoli River,Yenagoa,Bayelsa State.Shoreline data were extracted from satellite imagery over thirty years(1991-2021).The basis of ... The use of Digital Shoreline Analysis System was used to determine shoreline changes in Ikoli River,Yenagoa,Bayelsa State.Shoreline data were extracted from satellite imagery over thirty years(1991-2021).The basis of this study is to use Digital Shoreline Analysis System to determine erosion and accretion areas.The result reveals that the average erosion rate in the study area is 1.16 m/year and the accretion rate is 1.62 m/year along the Ikoli River in Ogbogoro Community in Yenagoa,Bayelsa State.The mean shoreline length is 5.24 km with a baseline length of 5.2 km and the area is classified into four zones to delineate properly area of erosion and accretion based on the five class of Linear regression rate,endpoint rate and weighted linear rate of which zone Ⅰ contain very high erosion and high erosion with an area of landmass 255449.93 m^(2) of 38%,zone Ⅱ contain moderate accretion,very high accretion and high accretion with a land area of 1666816.46 m^(2) with 24%,zone Ⅲ has very high erosion and high erosion with an area of landmass 241610.85 m^(2) of 34% and zone Ⅳ contain moderate accretion and high accretion with land area 30888.08 m^(2) with 4%.Out of the four zones,zone Ⅰ and Ⅱ were found to be eroding with 72% and zone Ⅱ and Ⅳ contain accretion with 28%.The result shows that 44% of the area have been eroded.Therefore,coastal engineers,planners,and shoreline zone management authorities can use DSAS to create more appropriate management plans and regulations for coastal zones and other coastal parts of the state with similar geographic features. 展开更多
关键词 Satellite imagery Erosion ACCRETION Yenagoa Linear regression rate Endpoint rate Weighted linear rate Digital Shoreline analysis System
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Study on Futon Patterns in Mural of Buddhist Temple in Wutai Mountain under Digital Vision
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作者 WANG Zhi-jun GAO Shuai-rui 《Journal of Literature and Art Studies》 2023年第3期199-209,共11页
Dao Xuan’s Gantonglu records:“About fifteen kilometers down from the southeast of the Wutai Mountain,there is the ancient Dafu Lingjiu Temple,and there are two Taoist temples in the east and west,where Buddhist matt... Dao Xuan’s Gantonglu records:“About fifteen kilometers down from the southeast of the Wutai Mountain,there is the ancient Dafu Lingjiu Temple,and there are two Taoist temples in the east and west,where Buddhist matters are fulfilled.According to ancient legend,it was made by Emperor Ming of the Han Dynasty”(Daoxuan,Tang Dynasty,p.257).It can be seen that Buddhism has been introduced into Wutai Mountain since the Eastern Han Dynasty,and Buddhist temple murals have been painted on the walls of temples with the introduction of Buddhism,playing the role of spreading scriptures and decorating the walls.The pattern of Buddha’s futon base in the murals reflects the worship and rank differences of Buddhist monks in different periods.As a medium of meditation and worship,futuan is also a ritual instrument in Buddhist legend,which is of great significance.The research on the style of futon from the perspective of the frescoes in the temple of Wutai Mountain mainly focuses on the historical evolution of the frescoes and futon,the research and analysis of the base shape,pattern,composition and color of the futon in the frescoes of the temple.Explore the religious significance and historical and cultural value behind the futon style. 展开更多
关键词 Mural paintings of Buddhist temple in Wutai Mountain FUTON the style digital analysis
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Bubble dynamics properties of B-particles in a quasi-2D gas-solid fluidized bed:Computational particle fluid dynamics numerical simulation and post-processed by digital image analysis technique
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作者 Zemin Yuan Zhong Huang +4 位作者 Guotao Qin Guanjia Zhao Suxia Ma Hairui Yang Guangxi Yue 《Particuology》 SCIE EI CAS CSCD 2024年第3期223-238,共16页
Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-t... Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-two-dimensional(quasi-2D)fluidized bed,including bubble equivalent diameter,bubble size distribution,average bubble density,bubble aspect ratio,bubble hold-up,bed expansion ratio,bubble radial position,and bubble velocity.The studies were performed by computational particle fluid dynamics(CPFD)numerical simulation and post-processed with digital image analysis(DIA)technique,at superficial gas velocities ranging from 2u_(mf) to 7u_(mf).The simulated results shown that the CPFD simulation combining with DIA technique post-processing could be used as a reliable method for simulating bubble dynamics properties in quasi-2D gas-solid fluidized beds.However,it seemed not desirable for the simulation of bubble motion near the air distributor at higher superficial gas velocity from the simulated average bubble density distribution.The superficial gas velocity significantly affected the bubble equivalent diameter and evolution,while it had little influence on bubble size distribution and bubble aspect ratio distribution for the same particles.Both time-averaged bubble hold-up and bed expansion ratio increased with the increase of superficial gas velocity.Two core-annular flow structures could be found in the fluidized bed for all cases.The average bubble rising velocity increased with the increasing bubble equivalent diameter.For bubble lateral movement,the smaller bubbles might be more susceptible,and superficial gas velocity had a little influence on the absolute lateral velocity of bubbles.The simulated results presented a valuable and novel approach for studying bubble dynamics properties.The comprehensive understanding of bubble dynamics behaviors in quasi-2D gas-solid fluidized beds would provide support in the design,operation,and optimization of gas-solid fluidized bed reactors. 展开更多
关键词 Bubble dynamics properties CPFD simulation Quasi-2D gas-solid fluidized bed Digital image analysis
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Assessment of liver fibrosis by a noninvasive method of transient elastography and biochemical markers 被引量:13
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作者 Masaki Kawamoto Toru Mizuguchi +6 位作者 Tadashi Katsuramaki Minoru Nagayama Hideki Oshima Hiroyuki Kawasaki Takayuki Nobuoka Yasutoshi Kimura Koichi Hirata 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第27期4325-4330,共6页
AIM: To assess the correlation between the fibrotic area (FA) as calculated by a digital image analysis (DIA), and to compare the diagnostic accuracy of FibroScan to the other existing Liver fibrosis (LF) marke... AIM: To assess the correlation between the fibrotic area (FA) as calculated by a digital image analysis (DIA), and to compare the diagnostic accuracy of FibroScan to the other existing Liver fibrosis (LF) markers using the receiver operating curve analysis.METHODS: We recruited 30 patients who underwent a liver resection for three different etiologies including normal liver, hepatitis B, and hepatitis C. Liver stiffness was measured by using a FibroScan. The FA was then calculated by DIA to evaluate LF in order to avoid any sampling bias. RESULTS: The FA negatively correlated with Prothrombin time (PT), platelet count, lecithin-cholesterol acyltransferase (LCAT), and pre-albumin (ALB). On the other hand, the findings of FibroScan correlated with similar markers. The FA positively correlated with FibroScan, serum hyaluronate level, and type Ⅳ collagen level, and aspartate transaminase to platelet ratio index (APRI). The area under the receiver operating curve for FibroScan was higher than that for the other markers, even though the statistical significance was minimal. CONCLUSION: Our findings suggest that FibroScan can initially be used to assess LF as an alternative to a liver biopsy (LB) and serum diagnosis, because it is a safe method with comparable diagnostic accuracy regarding the existing LF markers. 展开更多
关键词 CIRRHOSIS Digital image analysis Fibro-Scan Fibrotic area HYALURONATE Lecithin-cholesterol acyltransferase Liver fibrosis Pre-albumin
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Endoscopic ultrasound for the diagnosis of chronic pancreatitis 被引量:6
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作者 Tyler Stevens Mansour A Parsi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第23期2841-2850,共10页
Endoscopic ultrasound(EUS) has become a well accepted test for the diagnosis of chronic pancreatitis.Advantages include its ability to detect subtle and severe changes of the pancreatic duct and parenchyma,and its rel... Endoscopic ultrasound(EUS) has become a well accepted test for the diagnosis of chronic pancreatitis.Advantages include its ability to detect subtle and severe changes of the pancreatic duct and parenchyma,and its relative safety compared with endoscopic retrograde cholangiopancreatography.Limitations include inter-and intraobserver variability,operator dependence,and an incomplete understanding of its true accuracy.The Rosemont classif ication has recently been proposed as a weighted,standardized method that may improve EUS chronic pancreatitis scoring.This paper reviews the published evidence regarding the accuracy of EUS in chronic pancreatitis diagnosis,and enumerates the emerging technologies that have been recently studied which may ultimately improve endosonographic imaging of the pancreas. 展开更多
关键词 Chronic pancreatitis Contrast-enhanced endoscopic ultrasound DIAGNOSIS Digital image analysis ELASTOGRAPHY Endoscopic ultrasound Pancreatic function testing Rosemont classification
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Characteristics and influencing factors of proximity distance index on the northern Shaanxi Loess Plateau in China 被引量:6
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作者 ZHOU Yi LEI Xue +2 位作者 YANG Feng LI Yang WANG Bin 《Journal of Mountain Science》 SCIE CSCD 2019年第12期2844-2855,共12页
Topographic feature points and lines are the framework of topography,and their spatial distance relationship is an breakthrough in the study of topographical geometry,internal structure and development level.Proximity... Topographic feature points and lines are the framework of topography,and their spatial distance relationship is an breakthrough in the study of topographical geometry,internal structure and development level.Proximity distance(PD)is an indicator to describe the distance between the gully source point(GSP)and the watershed boundary.In the upstream catchment area,PDs can be expressed by the streamline proximity distance(SPD),as well as by the horizontal proximity distance(HPD)and the vertical proximity distance(VPD)in the horizontal and vertical dimensions,respectively.The series of indicators(e.g.,SPD,HPD and VPD)are important for quantifying the geomorphological development process of a loess basin because of the headward erosion of loess gullies.In this study,the digital elevation model data with 5 m resolution and a digital topographic analysis method are used for the statistical analyses of the SPD,VPD and HPD in 50 sample areas of 6 geomorphic types in the Loess Plateau of northern Shaanxi.The spatial characteristics and the influencing factors are also analysed.Results show that:1)Central tendencies for the HPDs and the VPDs for the whole study area and the six typical loess landforms are evident.2)Spatial patterns of the HPDs and the VPDs exhibit evident trends and zonal distributions over the whole study area.3)The HPDs have a strong positive correlation with gully density(GD)and hypsometric integral.The VPDs also correlates with GD to an extent.Vegetation cover,mean annual precipitation and loess thickness have stronger effects on the VPD than on the HPD. 展开更多
关键词 Digital elevation model(DEM) Proximity distance Terrain factor Digital terrain analysis Loess Plateau
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Study on Headland-Bay Sandy Coast Stability in South China Coasts 被引量:5
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作者 于吉涛 陈子燊 《China Ocean Engineering》 SCIE EI 2011年第1期1-13,共13页
Headland-bay beach equilibrium planform has been a crucial problem abroad to long-term sandy beach evolution and stabilization, extensively applied to forecast long-term coastal erosion evolvement and the influences o... Headland-bay beach equilibrium planform has been a crucial problem abroad to long-term sandy beach evolution and stabilization, extensively applied to forecast long-term coastal erosion evolvement and the influences of coastal engineering as well as long-term coastal management and protection. However, little concern focuses on this in China. The parabolic relationship is the most widely used empirical relationship for determining the static equilibrium shape of headland-bay beaches. This paper utilizes the relation to predict and classify 31 headland-bay beaches and concludes that these bays cannot achieve the ultimate static equilibrium planform in South China. The empirical bay equation can morphologically estimate beach stabilization state, but it is just a referential predictable means and is difficult to evaluate headland-bay shoreline movements in years and decades. By using Digital Shoreline Analysis System suggested by USGS, the rates of shoreline recession and accretion of these different headland-bay beaches are quantitatively calculated from 1990 to 2000. The conclusions of this paper include that (a) most of these 31 bays maintain relatively stable and the rates of erosion and accretion are relatively large with the impact of man-made constructions on estuarine within these bays from 1990 to 2000; (b) two bays, Haimen Bay and Hailingshan Bay, originally in the quasi-static equilibrium planform determined by the parabolic bay shape equation, have been unstable by the influence of coastal engineering; and (c) these 31 bays have different recession and accretion characters occuning in some bays and some segments. On the one hand, some bays totally exhibit accretion, but some bays show erosion on the whole. Shanwei Bay, Houmen Bay, Pinghai Bay and Yazhou Bay have the similar planforms, characterized by less accretion on the sheltering segment and bigger accretion on the transitional and tangential segments. On the other hand, different segments of some bays have two dissimilar evolvement characters. Dacheng Bay, Shenquan Bay, Hudong Bay, Wukan Bay, Fengjia Bay, Wuchang Bay, Lingshui Bay and Tufu Bay produce accretion on the tangential segment, erosion on the transitional segment and accretion on the sheltering segment. However, Guang'ao Bay, Haimen Bay, Jinghai Bay, Sanya Bay(a), Dajiao Bay, Hailingshan Bay, Hebei Bay, Fuhu Bay, Shuidong Bay, Wangcun Bay and Bomao Bay generate erosion on the tangential part, accretion on the transitional part and accretion on the sheltering part. It seems to imply some relations between headland-bay beach evolvement and controls on headland-bay beaches, which may possibly to classify headland-bay beach types and should be further studied. 展开更多
关键词 Headland-bay beaches parabolic bay shape equation digital shoreline analysis system end point rate
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Quantitative characterization of β-solidifying γ-TiAl alloy with duplex structure 被引量:5
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作者 Run-run XU Miao-quan LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第7期1993-2004,共12页
For precise plastic deformation,microstructure control is essential especially for β-solidifying γ-TiAl alloy with duplex structure.Based on stereology,the microstructure of isothermally compressed γ-TiAl alloy was... For precise plastic deformation,microstructure control is essential especially for β-solidifying γ-TiAl alloy with duplex structure.Based on stereology,the microstructure of isothermally compressed γ-TiAl alloy was divided into β_(0) grains,remnant α_(2)/γ lamellar colonies,α_(2) and γ grains.The results show that the volume fraction of β_(0) grains slightly increases in the isothermally compressed γ-TiAl alloy with the increase of height reduction.Meanwhile,the volume fractions of remnant α_(2)/γ lamellar colonies and α_(2) grains decrease.However,the volume fraction of γ grains increases from 64.39% to 78.47%.According to the quantitative results,the α→γ phase transformation was investigated in-depth,and it is found that isothermal compression accelerates the α→γ phase transformation.The first α→γ phase transformation is similar to ledge-controlled transformation,through which remnant α_(2)/γ lamellar colonies finally convert intoγgrains in isothermal compression.The second is achieved by α/γ phase interface immigration. 展开更多
关键词 TiAl alloy STEREOLOGY digital image analysis MICROSTRUCTURE phase transformation
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浸渍硅胶薄层色谱板分离钴和镍及数字图像分析法定量(英文) 被引量:2
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作者 P A MOHAMED NAJAR R G SONALI +1 位作者 M T NIMJE K V RAMANA RAO 《色谱》 CAS CSCD 北大核心 2012年第10期1081-1088,共8页
Thin layer chromatography(TLC) of cobalt and nickel has been performed on silica gel layers induced with alkali mediated cellulose extract.A novel combination of 10% aqueous solutions of Tween-20 and potassium thiocya... Thin layer chromatography(TLC) of cobalt and nickel has been performed on silica gel layers induced with alkali mediated cellulose extract.A novel combination of 10% aqueous solutions of Tween-20 and potassium thiocyanate in 1∶1(v/v) was identified as the best mobile phase for the selective separation of Co2+from Ni2+on the impregnated Silica Gel G layers.The chromatographic characteristics of the cations were studied and the limits of detection as well as the limits of quantification for Co2+and Ni2+were determined.The quantitative estimation of the cations was achieved from the digital image analysis of respective chromatograms.The proposed quantitative method was successfully applied with 0-0.50% error for the determination of Co2+from Ni2+in spiked samples of bauxite,soil and rock containing common cations such as Al3+,Fe2+,Ti4+,Zn2+,Mn2+,Cu2+,Cr6+,Mg2+,etc.under the optimized chromatographic conditions. 展开更多
关键词 thin layer chromatography(TLC) COBALT NICKEL quantification digital image analysis
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Requirements for implementation of artificial intelligence in the practice of gastrointestinal pathology 被引量:2
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作者 Hiroshi Yoshida Tomoharu Kiyuna 《World Journal of Gastroenterology》 SCIE CAS 2021年第21期2818-2833,共16页
Tremendous advances in artificial intelligence(AI)in medical image analysis have been achieved in recent years.The integration of AI is expected to cause a revolution in various areas of medicine,including gastrointes... Tremendous advances in artificial intelligence(AI)in medical image analysis have been achieved in recent years.The integration of AI is expected to cause a revolution in various areas of medicine,including gastrointestinal(GI)pathology.Currently,deep learning algorithms have shown promising benefits in areas of diagnostic histopathology,such as tumor identification,classification,prognosis prediction,and biomarker/genetic alteration prediction.While AI cannot substitute pathologists,carefully constructed AI applications may increase workforce productivity and diagnostic accuracy in pathology practice.Regardless of these promising advances,unlike the areas of radiology or cardiology imaging,no histopathology-based AI application has been approved by a regulatory authority or for public reimbursement.Thus,implying that there are still some obstacles to be overcome before AI applications can be safely and effectively implemented in real-life pathology practice.The challenges have been identified at different stages of the development process,such as needs identification,data curation,model development,validation,regulation,modification of daily workflow,and cost-effectiveness balance.The aim of this review is to present challenges in the process of AI development,validation,and regulation that should be overcome for its implementation in real-life GI pathology practice. 展开更多
关键词 Artificial intelligence Deep learning Digital image analysis Digital pathology Clinical implementation Gastrointestinal cancer
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A LINEAR APPROACH TO METRIC CIRCUMFERENCE COMPUTATIO FOR DIGITIZED CONVEX SHAPES 被引量:3
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作者 Chen Ken Zhao Pan Yang Rener 《Journal of Electronics(China)》 2008年第4期572-575,共4页
Metric measurement of digitized shapes is commonly applied in optical measuring systems.In this letter,three shape-related factors defined by the authors are used in the construction of amultiple linear regression mod... Metric measurement of digitized shapes is commonly applied in optical measuring systems.In this letter,three shape-related factors defined by the authors are used in the construction of amultiple linear regression model which is utilized to compute the circumference of the convex shapes inmillimeter unit.The model is first built upon the relationship hypothesis and then its adequacy ismathematically validated.The results of applying the developed model to the given number of convexshapes in a finite circumferential length range suggest that,in terms of percent error,the model pre-cision is to satisfaction by being within±4%.The test also shows the model’s robustness against theshape’s orientation anisotropy. 展开更多
关键词 Metric measurement Circumference computation Digital image analysis Modeling
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