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Segmentation algorithm of complex ore images based on templates transformation and reconstruction

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 385-389页

作者： Guo-ying Zhang guan-zhou Liu Hong Zhu School of Mechanical-Electrical and Information China University of Mining ＆ Technology Beijing 100083 China

Lots of noises and heterogeneous objects with various sizes coexist in a complex image,such as an ore image;the classical image thresholding method cannot effectively distinguish between *** segment ore objects with various sizes simultaneously,two adaptive windows in the image were chosen for each pixel;the gray value of windows was calculated by Otsu＇s threshold *** extract the object skeleton,the definition principle of distance transformation templates was *** ores linked together in a binary image were separated by distance transformation and gray *** seed region of each object was picked up from the local maximum gray region of the reconstruction *** from these seed regions,the watershed method was used to segment ore object *** proposed algorithm marks and segments most objects from complex images precisely.

关键词： ores image analysis image segmentation morphological transformation algorithms

Hot tensile deformation behavior and constitutive model of ZK61M high-strength magnesium alloy sheet

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Rare Metals 2021年第5期40卷 1182-1190页

作者： Liu Yang Yong-Chuan Duan ying-Ping guan Zhen-Hua Wang Key Laboratory of Advanced Forging&Stamping Technolnology and Science Ministry of Education of ChinaYanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

Hot deformation behavior of the annealed ZK61 M magnesium alloy sheet was explored using tensile tests with strain rates varying from 0.001 to 0.030 s^(-1) in temperatures range of 423-513 *** obtained results indicate that the flow stress increased with deformation temperature decreasing and strain rate *** recrystallization(DRX)occurs when the temperature is higher than 423 K,and the recrystallization volume fraction increases with temperature *** a given temperature,the measured DRX volume fraction at a higher strain rate is smaller than that at a lower strain *** are observed throughout the tested temperature ***,they grow larger as temperature *** average absolute relative error(AARE)of 2.65%proves that the peak stress predicted by the constitutive model is in good agreement with the experimental *** correlation coefficient(R’)obtained for the predicted stress and the experimental value considering the strain on the material constant are between 0.9831 and *** addition,AARE and root mean square error(RMSE)are less than 6.5%and 8.5 MPa,*** indicates that the deviation of the predicted value from the experimental value is small and the predictions of the proposed model are reliable.

关键词： ZK61M magnesium alloy sheet Hot tensile deformation Microstructure Constitutive model

Roles and application of exosomes in the development,diagnosis and treatment of gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 630-642页

作者： Xiao-Li guan Xiao-ying guan Zheng-Yi Zhang Department of General Medicine The Second Hospital of Lanzhou UniversityLanzhou 730030Gansu ProvinceChina Department of Pathology The Second Hospital of Lanzhou UniversityLanzhou 730030Gansu ProvinceChina

As important messengers of intercellular communication,exosomes can regulate local and distant cellular communication by transporting specific exosomal con-tents and can also promote or suppress the development and progression of gas-tric cancer(GC)by regulating the growth and proliferation of tumor cells,the tumor-related immune response and tumor *** transport bioactive molecules including DNA,proteins,and RNA(coding and noncoding)from donor cells to recipient cells,causing reprogramming of the target *** this review,we will describe how exosomes regulate the cellular immune respon-se,tumor angiogenesis,proliferation and metastasis of GC cells,and the role and mechanism of exosome-based therapy in human *** will also discuss the potential application value of exosomes as biomarkers in the diagnosis and treat-ment of GC and their relationship with drug resistance.

关键词： Exosomes Gastric cancer Immune regulation Diagnosis Cancer therapy

Mechanistic insights into the novel glucose-sensitive behavior of P(NIPAM-co-2-AAPBA)

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Science China Chemistry 2020年第3期63卷 377-385页

作者： Qingxian Wang Mian Fu ying guan Tony D.James Yongjun Zhang Key Laboratory of Functional Polymer Materials and State Key Laboratory of Medicinal Chemical Biology Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China Department of Chemistry University of BathClaverton DownBath BA27AYUK

A glucose-sensitive polymer,poly(N-isopropylacrylamide-co-2-acrylamidophenylboronic acid)(P(NIPAM-co-2-AAPBA)),was synthesized by reversible addition fragmentation chain transfer(RAFT)*** of glucose results in reduced solubility and hence increased turbidity,rather than the normal increase in solubility(decreased turbidity)observed for other PBA-based glucose-sensitive *** novel glucose-sensitive behavior is explained by a new mechanism,in which glucose acts as an additive and depresses the lower critical solution temperature(LCST)of the polymer,instead of increasing solubility by increasing the degree of ionization of the PBA *** and theoretic analysis for the influence of glucose on the thermal behavior of P(NIPAM-co-2-AAPBA)reveals that glucose depresses the LCST of P(NIPAM-co-2-AAPBA)copolymers in a two-stage manner,a fast decrease at low glucose concentrations followed by a slow decrease at high glucose *** low glucose concentrations,the binding of glucose with PBA groups on the polymer chain increases the number of glucose molecules proximal to the polymer which influences the thermal behavior of the polymer,causing a rapid decrease in ***,the transition occurs at a glucose concentration equal to the reciprocal of the binding constant between PBA and glucose,thus providing a novel method to determine the binding *** saccharides,including mannose,galactose and fructose,also depress the LCST of P(NIPAM-co-2-AAPBA)copolymer in the same way.

关键词： glucose-sensitive mechanism phenylboronic acid thermosensitive binding constant lower critical solution temperature polymers

Development of a non-cable whole tectorial membrane micro-robot for an endoscope

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1141-1149页

作者： Dong-dong YE Guo-zheng YAN Kun-dong WANG guan-ying MA Department of Instrument Shanghai Jiao Tong University Shanghai 200240 China

A novel non-cable whole tectorial membrane micro-robot for an endoscope is developed. The micro-robot we have fabricated and tested can propel itself in the intestine tract of a pig in an autonomous manner by earthworm-like locomotion. The silicone of bellow shape is laid over the outer surface of the micro-robot to reduce the affection of the viscoelastic properties of the intestine. Wireless power transfer and communication systems are employed to realize the non-cable locomotion of the mi-cro-robot. The prototype of the micro-robot is 13.5 mm in diameter and 108 mm in length. The experimental results show that the towing force for the micro-robot is about 0.8 N, which is much smaller than the maximum driving force 2.55 N of the linear actuator. The supplying power of the wireless power transfer system fulfills the needs of the micro-robot system and the mi-cro-robot can creep reliably in the large intestine of a pig and other contact environments.

关键词： Micro-robot Endoscope Intestine tract Silicone of bellow shape Linear actuator Wireless power

Transverse Bending Characteristics in U-channel Forming of Tailor Rolled Blank

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Journal of Iron and Steel Research International 2016年第12期23卷 1249-1254页

作者： Hua-wei ZHANG ying-ping guan Jia-lu WU Xiang-hua LIU School of Control Engineering Northeastern University at Qinhuangdao College of Mechanical Engineering Yanshan University Research Institute of Science and Technology Northeastern University

Research on the formability of tailor rolled blank （TRB） is of good practical significance and application value because of the enormous potential of TRB in the aspect of automobile lightweight. However, the forming of TRB is problematic because of the varying properties; especially, springback is a main challenge. The transverse bending （bending axis is perpendicular to the rolling direction） of TRB U channel was studied through simulation and experiment. The forming characteristics of TRB U channel during transverse bending were analyzed. The mechanisms of forming defects, including bending springback and thickness transition zone （TTZ） movement, were revealed. On this basis, effects of blank geometric parameters on springbaek and TTZ movement were discussed. The results indicate that springback and TTZ movement happen during transverse bending of TRB U-channel. Nonuni form stress distribution is the most fundamental reason for the occurrence of springback of TRB during transverse bending. Annealing can eliminate nonuniform stress distribution, and thus diminish springbaek of TRB, especially springback on the thinner side. Therefore, springback of the whole TRB becomes more uniform. However, annealing can increase the TTZ movement. Blank thickness and TTZ position are the main factors affecting the formability of TRB U-channel during transverse bending.

关键词： tailor rolled blank transverse bending springback U-channel annealing thickness transition zone

Kinetic analysis of austenite transformation for B1500HS high-strength steel during continuous heating

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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1508-1516页

作者： Mu-yu Li Dan Yao Liu Yang Hao-ran Wang ying-ping guan Key Laboratory of Advanced Forging&Stamping Technology and Science(Ministry of Education of China) Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

The dilatometric curves of B1500HS high-strength steel at different heating rates were measured by a Gleeble-3800 thermal simulator and analyzed to investigate the effect of heating rate on *** show that the value of starting temperature and ending temperature of austenite transformation increase with the rise of heating rates,whereas the temperature interval of austenite formation *** kinetic equation of austenite transformation was solved using the Johnson–Mehl–Avrami model,and the related parameters of the equation were analyzed by the Kissinger *** those calculations,the activation energy of austenite transformation is 1.01×10^6 J/mol,and the values of kinetic parameters n and ln k0 are 0.63 and 103.03,*** relationship between the volume fraction of austenite and the heating time at different heating rates could be predicted using the kinetic *** predicted and experimental results were compared to verify the accuracy of the kinetic *** microstructure etched by different corrosive solutions was analyzed,and the reliability of kinetic equation was further verified from the microscopic perspective.

关键词： B1500HS high-strength steel dilatometric curve austenite transformation kinetic equation Johnson-Mehl-Avuami model

卷曲螺旋结构域蛋白2通过促进线粒体自噬抑制帕金森病SH-SY5Y细胞凋亡

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中国组织工程研究 2025年第25期29卷 5403-5413页

作者：祝柳慧张歆悦朱洲海杨兴隆管莹刘彬昆明医科大学第一附属医院神经内科云南省昆明市650032 烟草与健康联合研究院云南省昆明市650106

背景:卷曲螺旋结构域蛋白2(coiled-coil-helix-coiled-coil-helix domain-containing 2,CHCHD2)能否调控PINK1/Parkin介导的线粒体自噬在帕金森病中发挥神经保护作用尚未可知。目的:探讨CHCHD2在6-羟基多巴胺诱导的帕金森病细胞模型中对PINK1/Parkin信号通路介导的线粒体自噬发挥的作用及机制。方法:利用重组质粒转染技术过表达或敲低CHCHD2,用6-羟基多巴胺构建SH-SY5Y细胞帕金森病模型后分对照组、模型组、过表达阴性对照+6-羟基多巴胺组、敲低阴性对照+6-羟基多巴胺组、过表达CHCHD2+6-羟基多巴胺组和敲低CHCHD2+6-羟基多巴胺组。Western blot及RT-qPCR检测CHCHD2的表达;Western blot检测LC3Ⅰ/Ⅱ、p62、MFN1、COXⅣ、DRP1、PINK1、Parkin、TIM23、Bax、Bcl-2及cleavedcaspase3蛋白表达;CCK-8、JC-1和活性氧试剂盒检测细胞活性、线粒体膜电位和活性氧水平,单丹磺酰尸胺染色观察细胞自噬情况,透射电镜观察自噬溶酶体。结果与结论:①与对照组相比,模型组细胞活性、线粒体膜电位及CHCHD2、PINK1、Parkin蛋白表达降低,活性氧水平、凋亡水平及LC3Ⅰ/Ⅱ、p62蛋白表达升高(P<0.05),并观察到自噬溶酶体的存在;②与模型组相比,过表达CHCHD2能降低细胞活性氧水平,升高线粒体膜电位及PINK1、Parkin和MFN1蛋白表达水平,并观察到线粒体自噬溶酶体增多,而敲低CHCHD2后有与上述相反的作用,并伴有COXⅣ、TIM23和p-DRP1蛋白表达的升高(P<0.05);③与模型组相比,过表达CHCHD2能减少细胞凋亡,上调Bcl-2并下调Bax及cleavedcaspase3蛋白的表达,而敲低CHCHD2后有与上述相反的作用(P<0.05);④结果提示,CHCHD2在6-羟基多巴胺诱导的帕金森病细胞模型中可以通过促进PINK1/Parkin介导的线粒体自噬改善线粒体功能从而减轻细胞凋亡发挥神经保护作用。

关键词：帕金森病卷曲螺旋结构域蛋白2 PINK1 Parkin 线粒体自噬线粒体功能细胞凋亡 6-羟基多巴胺 SH-SY5Y细胞

Correlation of magnetic resonance imaging quantitative parameters and apparent diffusion coefficient value with pathological breast cancer

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World Journal of Clinical Cases 2022年第21期10卷 7333-7340页

作者： Zhe Wang guan-ying Ren Qian Yin Qian Wang Department of Medical Imaging The No.2 Hospital of BaodingBaoding 071051Hebei ProvinceChina Department of Medical Oncology Affiliated Hospital of Hebei UniversityHebei Key Laboratory of Cancer Radiotherapy and ChemotherapyBaoding 071000Hebei ProvinceChina

BACKGROUND China ranks 120th worldwide for the incidence of breast cancer and 163rd for *** screening,diagnosis,and timely determination of the optimal treatment plan can help ensure clinical efficacy and *** To investigate the relationship between quantitative magnetic resonance imaging parameters,apparent diffusion coefficient value,pathological immunohistochemical status,and patient *** A total of 108 patients with breast cancer(breast cancer group)and 110 patients with benign breast tumors(benign group)confirmed by pathological examination at our Hospital from September 2013 to August 2016 were *** patients had undergone preoperative magnetic resonance imaging(MRI)examinations,and the quantitative parameters of MRI and apparent diffusion coefficient(ADC)values for the two groups were *** MRI quantitative parameters and ADC values of patients with different estrogen receptor(ER),progesterone receptor,and human epidermal growth factor receptor-2 expression were statistically *** relationship between the quantitative parameters of MRI and ADC values and patient recurrence was analyzed using receiver operating *** The measured values of the quantitative parameters of MRI-Ktrans,Kep,and Ve in the breast cancer group were higher than those in the benign group;the ADC value in the breast cancer group was lower than that in the benign group,and the difference was statistically significant(P<0.05).The Ktrans,Ve,and ADC values in patients with ER-positive breast cancer were significantly lower than those in patients with negative ER expression(P<0.05).After 5 years of follow-up,22 patients with breast cancer experienced postoperative *** Kep,Ve,and ADC values of the recurrence group were significantly lower than those of the non-recurrence group,and the difference was statistically significant(P<0.05).CONCLUSION MRI quantitative parameters and ADC are related to the expression of breast c

关键词： Magnetic resonance Apparent diffusion coefficient Breast cancer Immunohistochemistry Prognosis