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A saliency and Gaussian net model for retinal vessel segmentation

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Frontiers of Information Technology & Electronic Engineering 2019年第8期20卷 1075-1087页

作者： Lan-yan XUE Jia-wen LIN Xin-rong cao Shao-hua ZHENG Lun YU College of Physics and Information Engineering Fuzhou UniversityFuzhou350108China Institute of Computer and Information Fujian Agriculture and Forestry UniversityFuzhou350002China

Retinal vessel segmentation is a significant problem in the analysis of fundus images.A novel deep learning structure called the Gaussian net(GNET)model combined with a saliency model is proposed for retinal vessel segmentation.A saliency image is used as the input of the GNET model replacing the original *** GNET model adopts a bilaterally symmetrical *** the left structure,the first layer is upsampling and the other layers are *** the right structure,the final layer is max-pooling and the other layers are *** proposed approach is evaluated using the DRIVE *** results indicate that the GNET model can obtain more precise features and subtle details than the UNET *** proposed algorithm performs well in extracting vessel networks,and is more accurate than other deep learning *** vessel segmentation can help extract vessel change characteristics and provide a basis for screening the cerebrovascular diseases.

关键词： Retinal vessel segmentation Saliency model Gaussian net(GNET) Feature learning

Semisolid die forging process,microstructures and properties of AZ31 magnesium alloy mobile telephone shells

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 665-670页

作者： Ren-guo Guan Li-qing Chen Fu-rong cao Zhan-yong Zhao Yong Ren College of Materials and Metallurgy Northeastern University Shenyang 110004 China State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 China

A semisolid slurry of AZ31 magnesium alloy was prepared by vibrating wavelike sloping plate process,and the semisolid die forging process,microstructures,and properties of the magnesium alloy mobile telephone shell were *** semisolid forging process was performed on a YA32-315 four-column universal hydraulic *** microstructures were observed by optical microscopy,the hardness was analyzed with a model 450SVD Vickers hardometer,the mechanical properties was measured with a CMT5105 tensile test machine,and the fractograph of elongated specimens was observed by scanning electron microscopy （SEM）.The results reveal that with the increase of die forging force,the microstructures of the product become fine and dense.A lower preheating temperature and a longer dwell time are favorable to the formation of fine and dense *** optimum process conditions of preparing mobile telephone shells with excellent surface quality and microstructures are a die forging force of 2000 kN,a die preheating temperature of 250℃,and a dwell time of 240 *** solution treatment at 430℃ and aging at 220℃ for 8 h,the Vickers hardness is 61.7 and the ultimate tensile strength of the product is *** fractographs show the mixing mechanisms of quasi-cleavage fracture and ductile fracture.

关键词： magnesium alloys semisolid forging microstructure mechanical properties fracture

Cystic changes associated with pulmonary tuberculosis:a case report

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Chinese Medical Journal 2006年第13期119卷 1125-1128页

作者： CAI Hou-rong cao Min MENG Fan-qing LI Wei-chun Department of Pulmonary Medicine Drum Tower HospitalNanjing University Medical School Nanjing 210008 China

There are a wide range of computed tomography （CT） findings in patients with pulmonary tuberculosis, including diffuse or localized nodules, reticular opacities, ground glass attenuation, air trapping, consolidation, cavitation, fibrosis, lymph nodes enlargement, and septal thickening. However, CT findings of pulmonary tuberculosis that appeared as multiple cystic lesions were very rare. Herein, the CT findings appeared as multiple cystic lesions in a patient with pulmonary tuberculosis are reported.

关键词： pulmonary tuberculosis cystic lesion tomography, computed

Chemical and boron isotopic compositions of tourmaline in the Longtoushan hydrothermal gold deposit, Guangxi, China:implications for gold mineralization

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Acta Geochimica 2019年第2期38卷 277-291页

作者： Lihua Qian Jianqing Lai Shugen Zhang Lifang Hu rong cao Shilong Tao Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of Education School of Geosciences and Info-Physics Central South University

The Longtoushan hydrothermal gold deposit is located in the southwestern region of the Dayaoshan *** is widespread in the Longtoushan gold deposit and is mainly distributed in the rhyolite porphyry and associated cryptoexplosive breccia. The spatial distribution of tourmaline enrichment is similar to that of the gold orebody. Feldspar has been largely replaced by tourmaline in the rhyolite porphyry and cryptoexplosive *** microprobe analysis revealed that tourmalines in the Longtoushan deposit belong mainly to the alkali group and partly to the X-vacant group; they mostly fell in the schorl-dravite series field. Two distinct sets of dominant substitutions were observed: MgFe_(-1) and Al□(NaR2+)-1,where R = Fe, Mg. In addition, minor substitutions include(CaMg)(NaAl)_(-1) and FeAl_(-1). The calculated d11 B value for the mineralizing fluids ranged from-12.8 to-9.7%,which is typical of S-type granites, and boron-enriched fluids predominantly derived from rhyolitic melt. Part of the tourmaline from the rhyolite porphyry crystallized during the magmatic-hydrothermal stage, whereas most tourmalines from the deposit formed in the post-magmatic hydrothermal stage. The tourmalines were deposited from a relatively reduced and acidic fluid system, and the gold predominantly precipitated during the post-magmatic hydrothermal stage in the Longtoushan deposit.

关键词： Longtoushan gold deposit Tourmaline Oreforming fluids Boron isotopes

Pulmonary sarcoid-like granulomatosis induced by aluminum dust:report of a case and literature review

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Chinese Medical Journal 2007年第17期120卷 1556-1560页

作者： CAI Hou-rong cao Min MENG Fan-qing WEI Jing-yi Department of Pulmonary Medicine Affiliated Drum TowerHospital Nanjing University School of Medicine Nanjing 210008China

Awide range of pulmonary pathology is attributed to aluminum dust exposure, including interstitial fibrosis^1-5 desquamative interstitial pneumonia^6 and pulmonary alveolar proteinosis^7 To our knowledge, granulomatous lung disease induced by aluminum dust is rare, only two cases were reported in literatures^8.9 We had the opportunity to make a diagnosis of pulmonary sarcoid-like granulomatosis in a patient exposed to aluminum dust. Herein, we report the clinical history, radiographic and histopathological findings in this patient, and the detailed mineralogical analyses performed on lung tissue obtained by open lung biopsy.

关键词： aluminum dust granulomatosis scanning electron microscopy energy-dispersiveradiograph analysis mineralogical analysis

Application of Lactic Acid Bacteria(LAB) in Freshness Keeping of Tilapia Fillets as Sashimi

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Journal of Ocean University of China 2015年第4期14卷 675-680页

作者： cao rong LIU Qi CHEN Shengjun YANG Xianqing LI Laihao Key Laboratory of Aquatic Product Processing Ministry of Agriculture South China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Department of Food Engineering and Nutrition Yellow Sea Fisheries Research InstituteChinese Academy of Fishery Sciences

Aquatic products are extremely perishable food commodities. Developing methods to keep the freshness of fish represents a major task of the fishery processing industry. Application of Lactic Acid Bacteria(LAB) as food preservative is a novel approach. In the present study, the possibility of using lactic acid bacteria in freshness keeping of tilapia fillets as sashimi was examined. Fish fillets were dipped in Lactobacillus plantarum 1.19(obtained from China General Microbiological Culture Collection Center) suspension as LAB-treated group. Changes in K-value, APC, sensory properties and microbial flora were analyzed. Results showed that LAB treatment slowed the increase of K-value and APC in the earlier storage, and caused a smooth decrease in sensory score. Gram-negative bacteria dominated during refrigerated storage, with Pseudomonas and Aeromonas being relatively abundant. Lactobacillus plantarum 1.19 had no obvious inhibitory effect against these Gram-negatives. However, Lactobacillus plantarum 1.19 changed the composition of Gram-positive bacteria. No Micrococcus were detected and the proportion of Staphylococcus decreased in the spoiled LAB-treated samples. The period that tilapia fillets could be used as sashimi material extended from 24 h to 48 h after LAB treatment. The potential of using LAB in sashimi processing was confirmed.

关键词： lactic acid bacteria tilapia fillets sashimi freshness microbial flora

A New Approach for Estimating Kinetic Luminosity of Jet in AGNs

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Chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 39-49页

作者： Mao-Li Ma Xin-Wu cao Dong-rong Jiang Min-Feng Gu Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030

The Konigl inhomogeneous jet model can successfully reproduce most observational features of jets in active galactic nuclei （AGN）, when suitable physical parameters are adopted. We improve Konigl＇s calculations on the core emission from the jet with a small viewing angle θ0 - φ （φ is half opening angle of the conical jet）. The proper motion of the jet component provides a constraint on the jet kinematics. Based on the inhomogeneous jet model, we use the proper motion data of the jet component to calculate the minimal kinetic luminosity of the jet required to reproduce the core emission measured by the very-long- baseline interferometry （VLBI） for a sample of BL Lac objects. Our results show that the minimal kinetic luminosity is slightly higher than the bolometric luminosity for most sources in the sample, which implies that radiatively inefficient accretion flows （RIAFs） may be in those BL Lac objects, or/and the properties of their broad-line regions （BLRs） are significantly different from flat-spectrum radio-loud quasars.

关键词： galaxies jet -kinematics and dynamics theory - radiation mechanisms nonthermal-BL Lac objects general

Geochronology and Geochemistry of the Granites from the Longtoushan Hydrothermal Gold Deposit in the Dayaoshan Area,Guangxi:Implication for Petrogenesis and Mineralization

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Journal of Earth Science 2019年第2期30卷 309-322页

作者： Lihua Qian Jianqing Lai Lifang Hu rong cao Shilong Tao Bei You Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-physicsCentral South University

The gold mineralization in the Longtoushan hydrothermal gold deposit is concentrated within the contact zone of the granitic complex. Whole rock geochemistry and in-situ U-Pb and Hf isotopic data were used to constrain the genesis and age of the granites and related Cu-Au mineralization in the Longtoushan Deposit. The granites mainly consist of the granite porphyry, rhyolite porphyry, porphyritic granite and quartz porphyry. LA-ICP-MS U-Pb dating of zircons from the granite porphyry, rhyolite porphyry and quartz porphyry indicates that they intruded from ca. 94 to 97 Ma. These intrusions exhibit similar trace element characteristics, i.e., right-dipping REE patterns, depletion of Ba, Sr, P and Ti, and enrichment of Th, U, Nd, Zr and Hf. The εHf(t) values of zircons from the granite porphyry, rhyolite porphyry and quartz porphyry range from-26.81 to-8.19,-8.12 to-5.33, and-8.99 to-5.83, respectively, suggesting that they were mainly derived from the partial melting of the Proterozoic crust. The Cu-Au mineralization is mainly related to the rhyolite porphyry and porphyritic granite, respectively. The Longtoushan granites were most likely formed in a post-collisional extensional environment, and the deposit is a part of the Late Yanshanian magmatism related mineralization in the Dayaoshan area and its adjacent areas.

关键词： Longtoushan gold deposit rhyolite porphyry zircon U-Pb dating Hf isotopes petrogenesis Cu-Au mineralization

AlH_(3)在GAP/NG/BTTN中的贮存稳定性研究

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固体火箭技术 2024年第3期47卷 348-353页

作者：王榜庆裴宝林池旭辉杨根曹蓉赵程远张峰涛李小娜航天化学动力技术重点实验室襄阳441003 湖北航天化学技术研究所襄阳441003

针对三氢化铝(AlH_(3))在硝酸酯(NG/BTTN)增塑叠氮缩水甘油醚(GAP)高能推进剂中的贮存稳定性问题,采用XRD、SEM、元素分析等研究了不同温度下AlH_(3)在GAP/NG/BTTN中的分解特性。结果表明:相对于XRD,采用元素分析对AlH_(3)的含量进行定... 详细信息

针对三氢化铝(AlH_(3))在硝酸酯(NG/BTTN)增塑叠氮缩水甘油醚(GAP)高能推进剂中的贮存稳定性问题,采用XRD、SEM、元素分析等研究了不同温度下AlH_(3)在GAP/NG/BTTN中的分解特性。结果表明:相对于XRD,采用元素分析对AlH_(3)的含量进行定量表征的测试结果波动较小;AlH_(3)本体及其在GAP/NG/BTTN混合物中的分解释氢都存在诱导期、加速期和衰退期,70℃下诱导期均为6 d左右,GAP/NG/BTTN加快了AlH_(3)的分解释氢速率,在加速期内尤为明显,使得AlH_(3)分解加速期的时间跨度由22 d缩短为9 d;在诱导期内,NG/BTTN是影响AlH_(3)贮存稳定性的主要因素,GAP对AlH_(3)的贮存稳定性影响不明显;诱导期内纯AlH_(3)的分解活化能为197.01 kJ/mol,AlH_(3)/GAP/NG/BTTN混合物中AlH_(3)的分解活化能为199.58 kJ/mol,两者的分解活化能基本一致。

关键词：高能推进剂含能材料 AlH_(3) 活化能硝酸酯