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CA IX-targeted Ag_(2)S quantum dots bioprobe for NIR-II imaging-guided hypoxia tumor chemo-photothermal therapy
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作者 Xinyue Cui Zhuang Hu +3 位作者 Ruihan Li Peng Jiang Yongchang Wei Zilin Chen 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期878-888,共11页
Hypoxia is the common characteristic of almost all solid tumors,which prevents therapeutic drugs from reaching the tumors.Therefore,the development of new targeted agents for the accurate diagnosis of hypoxia tumors i... Hypoxia is the common characteristic of almost all solid tumors,which prevents therapeutic drugs from reaching the tumors.Therefore,the development of new targeted agents for the accurate diagnosis of hypoxia tumors is widely concerned.As carbonic anhydrase IX(CA IX)is abundantly distributed on the hypoxia tumor cells,it is considered as a potential tumor biomarker.4-(2-Aminoethyl)benzenesulfonamide(ABS)as a CA IX inhibitor has inherent inhibitory activity and good targeting effect.In this study,Ag_(2)S quantum dots(QDs)were used as the carrier to prepare a novel diagnostic and therapeutic bioprobe(Ag_(2)S@polyethylene glycol(PEG)-ABS)through ligand exchange and amide condensation reaction.Ag_(2)S@PEG-ABS can selectively target tumors by surface-modified ABS and achieve accurate tumor imaging by the near infrared-II(NIR-II)fluorescence characteristics of Ag_(2)S QDs.PEG modification of Ag_(2)S QDs greatly improves its water solubility and stability,and therefore achieves high photothermal stability and high photothermal conversion efficiency(PCE)of 45.17%.Under laser irradiation,Ag_(2)S@PEG-ABS has powerful photothermal and inherent antitumor combinations on colon cancer cells(CT-26)in vitro.It also has been proved that Ag_(2)S@PEG-ABS can realize the effective treatment of hypoxia tumors in vivo and show good biocompatibility.Therefore,it is a new efficient integrated platform for the diagnosis and treatment of hypoxia tumors. 展开更多
关键词 CA IX-targeted Hypoxia tumor combination therapy NIR-II imaging Photothermal effect
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Evaluating the Potentials of PLSR and SVR Models for Soil Properties Prediction Using Field Imaging,Laboratory VNIR Spectroscopy and Their Combination
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作者 Emna Karray Hela Elmannai +4 位作者 Elyes Toumi Mohamed Hedi Gharbia Souham Meshoul Hamouda Aichi Zouhaier Ben Rabah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1399-1425,共27页
Pedo-spectroscopy has the potential to provide valuable information about soil physical,chemical,and biological properties.Nowadays,wemay predict soil properties usingVNIRfield imaging spectra(IS)such as Prisma satell... Pedo-spectroscopy has the potential to provide valuable information about soil physical,chemical,and biological properties.Nowadays,wemay predict soil properties usingVNIRfield imaging spectra(IS)such as Prisma satellite data or laboratory spectra(LS).The primary goal of this study is to investigate machine learning models namely Partial Least Squares Regression(PLSR)and Support Vector Regression(SVR)for the prediction of several soil properties,including clay,sand,silt,organic matter,nitrate NO3-,and calcium carbonate CaCO_(3),using five VNIR spectra dataset combinations(%IS,%LS)as follows:C1(0%IS,100%LS),C2(20%IS,80%LS),C3(50%IS,50%LS),C4(80%IS,20%LS)and C5(100%IS,0%LS).Soil samples were collected at bare soils and at the upper(0–30 cm)layer.The data set has been split into a training dataset 80%of the collected data(n=248)and a validation dataset 20%of the collected data(n=61).The proposed PLSR and SVR models were trained then tested for each dataset combination.According to our results,SVR outperforms PLSR for both:C1(0%IS,100%LS)and C5(100%IS,0%LS).For Soil Organic Matter(SOM)prediction,it achieves(R^(2)=0.79%,RMSE=1.42%)and(R^(2)=0.76%,RMSE=1.3%),respectively.The data fusion has improved the soil property prediction.The highest improvement was obtained for the SOM property(R^(2)=0.80%,RMSE=1.39)when using the SVR model and applying the second Combination C2(20% of IS and 80%LS). 展开更多
关键词 Soil VNIR field imaging spectroscopy PLSR SVR VNIR data combination
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COMBINED IMAGING DIAGNOSIS OF PAROTID MASSES
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作者 俞光岩 邹兆菊 +3 位作者 王仪生 郝凤鸣 朱家瑞 李沙 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1990年第1期65-69,共5页
Computed tomography (CT), ultrasonography, sialography, and 99mTc scintigraphy were applied before operation to 108 patients with parotid masses. The results of each technique and the combined study of them were compa... Computed tomography (CT), ultrasonography, sialography, and 99mTc scintigraphy were applied before operation to 108 patients with parotid masses. The results of each technique and the combined study of them were compared with the pathological diagnosis. Ultrasonography was found to be a very effective diagnostic aid in determining the presence of space-occupying lesion in the parotid. CT was the best technique to provide adequately reliable informations regarding the location of the tumor and the relationship between tumor and surrounding tissues. For diagnosing the nature of tumors, ultrasonography combined with sialography was reliable. 99mTc scintigraphy was better than other techniques in diagnosis of adenolymphoma. The diagnostic accuracy of combined diagnosis (90.7%) was higher than those of ultrasonography (83%), CT (80.5%), sialography (79%), and 99mTc scintigraphy (13.9%) alone. The advantage of combined diagnosis was particularly obvious for the diagnosis of low-grade malignant tumors. 展开更多
关键词 combined imaging DIAGNOSIS OF PAROTID MASSES THAN
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A Sequence Image Matching Method Based on Improved High-Dimensional Combined Features 被引量:2
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作者 Leng Xuefei Gong Zhe +1 位作者 Fu Runzhe Liu Yang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第5期820-828,共9页
Image matching technology is theoretically significant and practically promising in the field of autonomous navigation.Addressing shortcomings of existing image matching navigation technologies,the concept of high-dim... Image matching technology is theoretically significant and practically promising in the field of autonomous navigation.Addressing shortcomings of existing image matching navigation technologies,the concept of high-dimensional combined feature is presented based on sequence image matching navigation.To balance between the distribution of high-dimensional combined features and the shortcomings of the only use of geometric relations,we propose a method based on Delaunay triangulation to improve the feature,and add the regional characteristics of the features together with their geometric characteristics.Finally,k-nearest neighbor(KNN)algorithm is adopted to optimize searching process.Simulation results show that the matching can be realized at the rotation angle of-8°to 8°and the scale factor of 0.9 to 1.1,and when the image size is 160 pixel×160 pixel,the matching time is less than 0.5 s.Therefore,the proposed algorithm can substantially reduce computational complexity,improve the matching speed,and exhibit robustness to the rotation and scale changes. 展开更多
关键词 SEQUENCE image MATCHING navigation DELAUNAY TRIANGULATION HIGH-DIMENSIONAL combined feature k-nearest NEIGHBOR
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The appliances and prospects of aurum nanomaterials in biodiagnostics, imaging, drug delivery and combination therapy 被引量:2
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作者 Dan Yang Feiyang Deng +4 位作者 Dechun Liu Bo He Bing He Xing Tang Qiang Zhang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第4期349-364,共16页
Aurum nanomaterials(ANM), combining the features of nanotechnology and metal elements, have demonstrated enormous potential and aroused great attention on biomedical applications over the past few decades. Particularl... Aurum nanomaterials(ANM), combining the features of nanotechnology and metal elements, have demonstrated enormous potential and aroused great attention on biomedical applications over the past few decades. Particularly, their advantages, such as controllable particle size, flexible surface modification, higher drug loading, good stability and biocompatibility, especially unique optical properties, promote the development of ANM in biomedical field. In this review, we will discuss the advanced preparation process of ANM and summarize their recent applications as well as their prospects in diagnosis and therapy. Besides, multi-functional ANM-based theranostic nanosystems will be introduced in details, including radiotherapy(RT), photothermal therapy(PTT), photodynamic therapy(PDT), immunotherapy(IT), and so on. 展开更多
关键词 Gold NANOMATERIALS imaging and biodiagnostics Drug delivery PHOTOTHERMAL THERAPY IMMUNOTHERAPY combination THERAPY
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Accuracy of combined PET/CT in image-guided interventions of liver lesions: An ex-vivo study
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作者 Patrick Veit Christiane Kuehle +3 位作者 Thomas Beyer Hilmar Kuehl Andreas Bockisch Gerald Antoch 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第15期2388-2393,共6页
AIM: Positioning of interventional devices in liver lesions is a challenging task if only CT is available. We investigated the potential benefit of combined PET/CT images for localization of interventional devices in... AIM: Positioning of interventional devices in liver lesions is a challenging task if only CT is available. We investigated the potential benefit of combined PET/CT images for localization of interventional devices in interventional liver studies. METHODS: Thirty lesions each of hyperdense, isodense and hypodense attenuation compared to normal liver parenchyma were injected into 15 ex-vivo pig livers. All lesions were composed of the same amounts of gelatine containing 0.5 MBq of ^18F-FDG. Following lesion insertion, an interventional needle was placed in each lesion under CT-guidance solely. After that, a PET/CT study was performed. The localization of the needle within the lesion was assessed for CT alone and PET/CT and the root mean square (RMS) was calculated. Results were compared with macroscopic measurements after lesion dissection serving as the standard of reference. RESULTS: In hypo- and isodense lesions PET/CT proved more accurate in defining the position of the interventional device when compared with CT alone. The mean RMS for CT and PET/CT differed significantly in isodense and hypodense lesions. No significant difference was found for hyperdense lesions. CONCLUSION: Combined FDG-PET/CT imaging provides more accurate information than CT alone concerning the needle position in FDG-PET positive liver lesions. Therefore combined PET/CT might be potentially beneficial not only for localization of an interventional device, but may also be beneficial for guidance in interventional liver procedures. 展开更多
关键词 Liver biopsy Radiofrequency ablation combined PET/CT ex-vivo study image guided interventions
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Feasibility of 3.0 T diffusion-weighted nuclear magnetic resonance imaging in the evaluation of functional recovery of rats with complete spinal cord injury 被引量:7
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作者 Duo Zhang Xiao-hui Li +1 位作者 Xu Zhai Xi-jing He 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第3期412-418,共7页
Diffusion tensor imaging is a sensitive way to reflect axonal necrosis and degeneration, glial cell regeneration and demyelination following spinal cord injury, and to display microstructure changes in the spinal cord... Diffusion tensor imaging is a sensitive way to reflect axonal necrosis and degeneration, glial cell regeneration and demyelination following spinal cord injury, and to display microstructure changes in the spinal cord in vivo. Diffusion tensor imaging technology is a sensitive method to diagnose spinal cord injury; fiber tractography visualizes the white matter fibers, and directly displays the structural integrity and resultant damage of the fiber bundle. At present, diffusion tensor imaging is restricted to brain examinations, and is rarely applied in the evaluation of spinal cord injury. This study aimed to explore the fractional anisotropy and apparent diffusion coefficient of diffusion tensor magnetic resonance imaging and the feasibility of diffusion tensor tractography in the evaluation of complete spinal cord injury in rats. The results showed that the average combined scores were obviously decreased after spinal cord transection in rats, and then began to increase over time. The fractional anisotropy scores after spinal cord transection in rats were significantly lower than those in normal rats (P 〈 0.05); the apparent diffusion coefficient was significantly increased compared with the normal group (P 〈 0.05). Following spinal cord transection, fractional anisotropy scores were negatively correlated with apparent diffusion coefficient values (r = -0.856, P 〈 0.01), and positively correlated with the average combined scores (r = 0.943, P 〈 0.01), while apparent diffusion coefficient values had a negative correlation with the average combined scores (r = -0.949, P 〈 0.01). Experimental findings suggest that, as a non-invasive examination, diffusion tensor magnetic resonance imaging can provide qualita- tive and quantitative information about spinal cord injury. The fractional anisotropy score and apparent diffusion coefficient have a good correlation with the average combined scores, which reflect functional recovery after spinal cord injury. 展开更多
关键词 nerve regeneration spinal cord injury spinal cord transection average combined score magnetic resonance imaging diffusion tensor imaging fractional anisotropy apparent diffusioncoefficient fiber tractography neural regeneration
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Contrast-enhanced ultrasound in association with serum biomarkers for differentiating combined hepatocellular-cholangiocarcinoma from hepatocellular carcinoma and intrahepatic cholangiocarcinoma 被引量:14
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作者 Jie Yang Ya-han Zhang +5 位作者 Jia-Wu Li Ying-Yu Shi Jia-Yan Huang Yan Luo Ji-Bin Liu Qiang Lu 《World Journal of Gastroenterology》 SCIE CAS 2020年第46期7325-7337,共13页
BACKGROUND Combined hepatocellular-cholangiocarcinoma(CHC)is a rare type of primary liver cancer.Due to its complex histopathological characteristics,the imaging features of CHC can overlap with those of hepatocellula... BACKGROUND Combined hepatocellular-cholangiocarcinoma(CHC)is a rare type of primary liver cancer.Due to its complex histopathological characteristics,the imaging features of CHC can overlap with those of hepatocellular carcinoma(HCC)and intrahepatic cholangiocarcinoma(ICC).AIM To investigate the possibility and efficacy of differentiating CHC from HCC and ICC by using contrast-enhanced ultrasound(CEUS)Liver Imaging Reporting and Data System(LI-RADS)and tumor biomarkers.METHODS Between January 2016 and December 2019,patients with histologically confirmed CHC,ICC and HCC with chronic liver disease were enrolled.The diagnostic formula for CHC was as follows:(1)LR-5 or LR-M with elevated alphafetoprotein(AFP)and carbohydrate antigen 19-9(CA19-9);(2)LR-M with elevated AFP and normal CA19-9;or(3)LR-5 with elevated CA19-9 and normal AFP.The sensitivity,specificity,accuracy and area under the receiver operating characteristic curve were calculated to determine the diagnostic value of the criteria.RESULTS After propensity score matching,134 patients(mean age of 51.4±9.4 years,108 men)were enrolled,including 35 CHC,29 ICC and 70 HCC patients.Based on CEUS LI-RADS classification,74.3%(26/35)and 25.7%(9/35)of CHC lesions were assessed as LR-M and LR-5,respectively.The rates of elevated AFP and CA19-9 in CHC patients were 51.4%and 11.4%,respectively,and simultaneous elevations of AFP and CA19-9 were found in 8.6%(3/35)of CHC patients.The sensitivity,specificity,positive predictive value,negative predictive value,accuracy and area under the receiver operating characteristic curve of the aforementioned diagnostic criteria for discriminating CHC from HCC and ICC were 40.0%,89.9%,58.3%,80.9%,76.9%and 0.649,respectively.When considering the reported prevalence of CHC(0.4%-14.2%),the positive predictive value and NPV were revised to 1.6%-39.6%and 90.1%-99.7%,respectively.CONCLUSION CHCs are more likely to be classified as LR-M than LR-5 by CEUS LI-RADS.The combination of the CEUS LI-RADS classification with serum tumor markers shows high specificity but low sensitivity for the diagnosis of CHC.Moreover,CHC could be confidently excluded with high NPV. 展开更多
关键词 combined hepatocellular-cholangiocarcinoma Contrast-enhanced ultrasound Liver imaging reporting and data system Sensitivity Diagnosis Liver neoplasms
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Combined hepatocellular and cholangiocellular carcinoma presenting with radiological characteristics of focal nodular hyperplasia 被引量:4
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作者 Inneke Willekens Anne Hoorens +3 位作者 Caroline Geers Bart Op de Beeck Frederik Vandenbroucke Johan de Mey 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第31期3940-3943,共4页
Combined hepatocellular and cholangiocellular carcinoma (cHCC-CC) is a rare tumor type containing unequivocal elements of both hepatocellular carcinoma and cholangiocarcinoma that are intimately mixed. Although these ... Combined hepatocellular and cholangiocellular carcinoma (cHCC-CC) is a rare tumor type containing unequivocal elements of both hepatocellular carcinoma and cholangiocarcinoma that are intimately mixed. Although these tumors are usually considered to be more related to hepatocellular carcinoma than to cholangiocarcinoma, they sometimes, in contrast to hepatocellular carcinoma, contain a significant amount of fibrous stroma. This might in some cases explain atypical radiological features. We report a case of a cHCC-CC in a 47-year-old female that resembled focal nodular hyperplasia on Magnetic Resonance Imaging. Correlation of imaging and serum levels of α-fetoprotein and CA19.9 can help to make the correct diagnosis preoperatively. 展开更多
关键词 combined hepatocellular Cholangiocellular carcinoma Magnetic resonance imaging
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AN INVERSE DESIGN OF ELECTROSTATIC FOCUSING FIELD FOR ELECTROSTATIC AND MAGNETIC IMAGING 被引量:1
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作者 倪国强 周立伟 +1 位作者 金伟其 方二伦 《Journal of Electronics(China)》 1990年第1期6-14,共9页
An inverse design of electrostatic focusing field for electrostatic and magneticimaging is investigated.Using the potential superimposition theorem of electrostatic field inmulti-electrode system,a mathematical model ... An inverse design of electrostatic focusing field for electrostatic and magneticimaging is investigated.Using the potential superimposition theorem of electrostatic field inmulti-electrode system,a mathematical model has been developed and an optimization methodhas been introduced into computation for designing the electrostatic focusing field of the imagingsystem. 展开更多
关键词 Photoelectronic imaging ELECTRON optics ELECTROSTATIC and magnetic combined FOCUSING INVERSE design of ELECTRON optical system CATHODE LENS
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A Fast Image Matching Algorithm Using a Combination of Line Segment Features 被引量:1
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作者 FU Runzhe LENG Xuefei +2 位作者 ZHU Yiming LIU Rui HAO Xiang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第3期501-511,共11页
The scene matching navigation is a research focus in the field of autonomous navigation,but the real-time performance of image matching algorithm is difficult to meet the needs of real navigation systems.Therefore,thi... The scene matching navigation is a research focus in the field of autonomous navigation,but the real-time performance of image matching algorithm is difficult to meet the needs of real navigation systems.Therefore,this paper proposes a fast image matching algorithm.The algorithm improves the traditional line segment extraction algorithm and combines with the Delaunay triangulation method.By combining the geometric features of points and lines,the image feature redundancy is reduced.Then,the error with confidence criterion is analyzed and the matching process is completed.The simulation results show that the proposed algorithm can still work within 3°rotation and small scale variation.In addition,the matching time is less than 0.5 s when the image size is 256 pixel×256 pixel.The proposed algorithm is suitable for autonomous navigation systems with multiple feature distribution and higher real-time requirements. 展开更多
关键词 image matching NAVIGATION Hough transform Delaunay triangulation combined feature
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Image Denoising Combining the P-M Model and the LLT Model 被引量:1
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作者 Qian Yang 《Journal of Computer and Communications》 2015年第10期22-30,共9页
In this paper, we present a noise removal technique by combining the P-M model with the LLT model. The combined technique takes full use of the advantage of both filters which is able to preserve edges and simultaneou... In this paper, we present a noise removal technique by combining the P-M model with the LLT model. The combined technique takes full use of the advantage of both filters which is able to preserve edges and simultaneously overcomes the staircase effect. We use a weighting function in our model, and compare this model with the P-M model as well as other fourth-order functional both in theory and numerical experiment. 展开更多
关键词 P-M MODEL LLT MODEL FOURTH-ORDER PDES combinATION image DENOISING
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Mechanical properties and damage characteristics of solidified body-coal combination in continuous driving and gangue backfilling 被引量:7
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作者 Yi Tan Hao Cheng +4 位作者 Wenbing Guo Erhu Bai Shaopu Zhang Yu Wang Zihao Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第10期1217-1228,共12页
Recovery of the coal buried under buildings,railways and water bodies and the residual coal in irregularly arranged fully mechanized mining faces is a common engineering problem facing underground coal mining.In this ... Recovery of the coal buried under buildings,railways and water bodies and the residual coal in irregularly arranged fully mechanized mining faces is a common engineering problem facing underground coal mining.In this study,a mining technology of continuous driving and gangue backfilling(CDGB)was proposed.The technology,which can not only alleviate ground subsidence and gangue discharge,but also release the above-mentioned coals,contributes to green and efficient sustainable development of mining.The stability of the system of the solidified body-reserved coal pillar combination(S-C combination)is crucial to the CDGB technology.Therefore,it is of great significance to explore the mechanical and damage characteristics of S-C combination in the synergistic bearing process.First,four sets of differentshaped S-C combination specimens were fabricated and a S-C combination bearing structure in CDGB was constructed to explore the differences in mechanical characteristics and damage modes of different-shaped S-C combination specimens during CDGB.Subsequently,their surface strain field evolutions and acoustic emission(AE)response characteristics in the load-bearing process were obtained with the aid of the digital image correlation technique and the AE signal monitoring system.Furthermore,a damage evolution model based on AE parameters and mechanical parameters was established to clarify the damage evolution law.The following results were obtained:(1)The free area of S-C combination can serve as a quantitative index to evaluate the stability of the overburden control system;(2)The concept of critical value k of the free area was first proposed.When the free area exceeds the critical value k(free area ratio greater than 1.13),the deformation resistance and the free area changes becomes negatively correlated;(3)As the free area expands,the failure of the S-C combination specimen evolves from tensile failure to shear failure.The distribution characteristics of the axial strain field also verified such a change in the failure mode;(4)When the free area expands,the peak AE count gradually changes from“double peaks”to“a single peak”.In this process,the expansion of free area shortens the time for accumulating and releasing energy during loading.Micro cracks generated in the specimen change from a phased steep growth to a continuous increase,and the process in which micro cracks develop,converge,intersect and connect to form macro cracks accelerates.The damage evolution law concluded based on AE parameters and mechanical parameters can well characterize the damage evolution process of S-C combination,providing certain reference for the study on the synergistic bearing of S-C combination during CDGB. 展开更多
关键词 Continuous driving and gangue backfilling Solidified body-coal combination Mechanical properties Damage characteristics Digital image correlation technology Acoustic emission
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Real time detection of antibody-antigen interaction using a laser scanning confocal imaging-surface plasmon resonance system 被引量:4
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作者 Zhang Hong-Yan Yang Li-Quan +5 位作者 Meng Lan Nie Jia-Cai Ning Ting-Yin Liu Wei-Min Sun Jia-Yu Wang Peng-Fei 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期224-228,共5页
A laser scanning confocal imaging-surface plasmon resonance (LSCI-SPR) instrument integrated with a wavelength-dependent surface plasmon resonance (SPR) sensor and a laser scanning confocal microscopy (LSCM) is ... A laser scanning confocal imaging-surface plasmon resonance (LSCI-SPR) instrument integrated with a wavelength-dependent surface plasmon resonance (SPR) sensor and a laser scanning confocal microscopy (LSCM) is built to detect the bonding process of human IgG and fluorescent-labeled affinity purified antibodies in real time. The shifts of resonant wavelength at different reaction time stages are obtained by SPR, corresponding well with the changes of the fluorescence intensity collected by using LSCM. The instrument shows the merits of the combination and complementation of the SPR and LSCM, with such advantages as quantificational analysis, high spatial resolution and real time monitor, which are of great importance for practical applications in biosensor and life science. 展开更多
关键词 laser scanning confocal imaging-surface plasmon resonance combinATION COMPLEMENTATION real time
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Image Combination Analysis in SPECAN Algorithm of Spaceborne SAR
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作者 臧铁飞 李方慧 龙腾 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期251-254,共4页
An analysis of image combination in SPECAN algorithm is delivered in time frequency domain in detail and a new image combination method is proposed. For four multi looks processing one sub aperture data in every th... An analysis of image combination in SPECAN algorithm is delivered in time frequency domain in detail and a new image combination method is proposed. For four multi looks processing one sub aperture data in every three sub apertures is processed in this combination method. The continual sub aperture processing in SPECAN algorithm is realized and the processing efficiency can be dramatically increased. A new parameter is also put forward to measure the processing efficient of SAR image processing. Finally, the raw data of RADARSAT are used to test the method and the result proves that this method is feasible to be used in SPECAN algorithm of spaceborne SAR and can improve processing efficiently. SPECAN algorithm with this method can be used in quick look imaging. 展开更多
关键词 synthetic aperture radar SPECAN image combination quick look image
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PLG-g-mPEG Mediated Multifunctional Nanoparticles for Photoacoustic Imaging Guided Combined Chemo/Photothermal Antitumor Therapy 被引量:1
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作者 Chong Liu Ling Li +3 位作者 Zhao-Pei Guo Lin Lin Yan-Hui Li Hua-Yu Tian 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第4期538-546,I0007,共10页
Under laser irradiation,photothermal therapy(PTT)effectively ablates tumors above 50℃.However,hyperthermia can cause additional damage due to the inevitable heat spread to surrounding healthy tissue.Herein,nanopartic... Under laser irradiation,photothermal therapy(PTT)effectively ablates tumors above 50℃.However,hyperthermia can cause additional damage due to the inevitable heat spread to surrounding healthy tissue.Herein,nanoparticles named as GI@P NPs were designed for enhanced PTT with heat shock protein 90(HSP90)inhibition at temperatures below 50℃to achieve optimal cancer therapy and avoid surrounding damage.GI@P NPs were done by co-loading Garcinia cambogia acid(GA)and photosensitizer IR783 in polymer PLG-g-mPEG to form a nanomedicine,where IR783 with excellent photoacoustic(PA)signal acted as an excellent photothermal therapeutic agent that converted the laser energy into heat to kill tumor cells,GA was used as antitumor drug for chemotherapy and an inhibitor of HSP90 to overcome the heat resistance of tumors for efficient cryo-photothermal therapy,and PLG-g-mPEG can encapsulate IR783 and GA to increase biocompatibility and accumulate effectively in the tumor.After GI@P NPs were injected into the mice,we could observe that the PA signals gradually increased in the tumor region and showed the strongest PA signals at 12 h.Under laser irradiation,the tumor temperature of the mice could raise to about 43.5℃,and the tumor was significantly inhibited after long-term monitoring by PA imaging.As a result,gentle PTT produced by GI@P NPs exhibited good antitumor effects at relatively low temperature and minimized nonspecific thermal damage to normal tissues.The GI@P NPs as nanomedicine enriched our understanding of various applications of polymeric carriers,especially in the biomedical field. 展开更多
关键词 Mild-temperature photothermal therapy Photoacoustic imaging Polymer carrier combination therapy Co-loading
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Geometric Calibration and Image Quality Assessment of High Resolution Dual-Camera Satellite
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作者 Zhou Fang Xinrong Wang +4 位作者 Wei Ji Meng Xu Yinan Zhang Yan Li Longfei Li 《Journal of Beijing Institute of Technology》 EI CAS 2021年第2期125-138,共14页
The evaluation of geometric calibration accuracy of high resolution satellite images has been increasingly recognized in recent years.In order to evaluate geometric accuracy for dual-camera satellite images based on t... The evaluation of geometric calibration accuracy of high resolution satellite images has been increasingly recognized in recent years.In order to evaluate geometric accuracy for dual-camera satellite images based on the ground control points(GCP),a rigorous geometric imaging model,which was based on the collinear equation of the probe directional angle and the optimized tri-axial attitude determination(TRIAD)algorithm,is presented.Two reliable test fields in Tianjin and Jinan(China)were utilized for geometric accuracy validation of Pakistan Remote Sensing Satellite-1.The experimental results demonstrate a certain deviation of the on-orbit calibration result from the initial design values of the calibration parameters.Therefore,on-orbit geometric calibration is necessary for optical satellite imagery.Within this research,the geometrical performances including positioning accuracy without/with GCP and band registration of the dual-camera satellite were analyzed in detail,and the results of geometric image quality are assessed and discussed.As a result,it is feasible and necessary to establish such a geometric calibration model to evaluate the geometric quality of dual-camera satellite. 展开更多
关键词 geometric calibration image quality dual-camera high resolution satellite
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Nondestructive analysis by combined X-ray tomography on a synchrotron radiation facility 被引量:1
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作者 DENG Biao YU Xiaohan LIAiguo XU Hongjie 《Nuclear Science and Techniques》 SCIE CAS CSCD 2007年第5期257-260,共4页
A nondestructive X-ray analysis technique combining transmission tomography, fluorescence tomography and Compton tomography based on synchrotron radiation is described. This novel technique will be an optional experim... A nondestructive X-ray analysis technique combining transmission tomography, fluorescence tomography and Compton tomography based on synchrotron radiation is described. This novel technique will be an optional experimental technique at SSRF's hard X-ray micro-focusing beamline under construction at present. An experimental result of combined X-ray tomography is obtained in NE-5A station of PF. The reconstructed images of test objects are given. 展开更多
关键词 X线扫描 图象重列 同步加速器 物理实验
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一种组合电极电容层析成像重建图像融合方法 被引量:1
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作者 张立峰 赵建海 华回春 《计量学报》 CSCD 北大核心 2024年第1期38-43,共6页
提出一种基于电容层析成像(ECT)组合电极重建图像及层次聚类的ECT图像融合方法。首先,构建组合8电极及12电极ECT阵列传感器,研究2种组合传感器激励测量方案;其次,采用层次聚类法对两种组合电极ECT重建图像进行聚类,从而消除重建过程中... 提出一种基于电容层析成像(ECT)组合电极重建图像及层次聚类的ECT图像融合方法。首先,构建组合8电极及12电极ECT阵列传感器,研究2种组合传感器激励测量方案;其次,采用层次聚类法对两种组合电极ECT重建图像进行聚类,从而消除重建过程中产生的伪影;最后,将聚类后的2种图像再进行小波融合重建。实验结果表明,相较于原始重建图像,所提方法重建图像平均相对误差最小,最大降幅达到23.4%,平均相关系数最大,最大增幅达到10.56%。 展开更多
关键词 计量学 电容层析成像 组合电极 图像重建 图像融合 油-气两相流
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正十二烷喷雾火焰中碳烟的瞬态生成特性
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作者 玄铁民 史智钊 +2 位作者 商伟伟 何志霞 王谦 《西安交通大学学报》 EI CAS CSCD 北大核心 2024年第3期15-24,共10页
针对压燃式发动机中碳烟演化过程难以被实验准确捕捉的问题,研究了高温高压环境中正十二烷喷雾燃烧焰中碳烟瞬态生成特性及动力学行为,在实验方面,应用消光辐射联合技术以及燃烧成像测速技术,同步获得高温高压环境中单孔喷油器正十二烷... 针对压燃式发动机中碳烟演化过程难以被实验准确捕捉的问题,研究了高温高压环境中正十二烷喷雾燃烧焰中碳烟瞬态生成特性及动力学行为,在实验方面,应用消光辐射联合技术以及燃烧成像测速技术,同步获得高温高压环境中单孔喷油器正十二烷喷雾燃烧火焰中的碳烟体积分数、碳烟温度和碳烟速度场的瞬态分布;数值计算方面,基于OpenFOAM环境,发展欧拉喷雾模型和非稳态火焰面进度变量湍流燃烧模型的耦合模型,喷雾燃烧过程的数值计算结果与实验数据有高度的一致性。研究结果表明:相比于参考工况,低喷油压力工况火焰浮起长度更短,碳烟在当量比Φ>2区间驻留时间更长,推动了碳烟的生成,碳烟峰值质量增加了80%;高温环境工况碳烟在当量比Φ>2区间驻留时间没有明显差异,但更短的火焰浮起长度使得燃料在更高的当量比开始燃烧,导致其碳烟峰值质量增加了88%;富氧工况的燃烧温度最高,碳烟粒子运动速度增大,使得碳烟在当量比Φ>2区间驻留时间明显减少,同时火焰内部当量比较小,因而碳烟峰值质量减少了42%。 展开更多
关键词 正十二烷 消光辐射联合技术 欧拉喷雾模型 碳烟瞬态生成特性
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