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A model for predicting the segregation directions of binary Geldart B particle mixtures in bubbling fluidized beds

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Particuology 2024年第7期90卷 340-349页

作者： Chenmin Liu Yuemin Zhao Yanjiao Li Yuqing Feng Chenlong Duan chenyang zhou Liang Dong Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationChina University of Mining and TechnologyXuzhou221116China School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou221116China Mineral Resources Business Unit CSIROClaytonVIC 3169Australia

In gas fluidization processes involving different types of particles,the mixing or segregation behavior of the solid mixture is crucial to the overall outcome of the *** study develops a model to predict the segregation directions of binary mixtures of Geldart B particles with density and size differences in bubbling fluidized *** proposed model was established by combining the particle segregation model,a previous particle segregation model,with a derived bed voidage equation of the bubbling fluidization based on the two-phase *** model was then analyzed with different function graphs of the model equations under various *** results indicated that an increase in gas velocity or volume fraction of larger particles would strengthen size segregation,causing the larger and less dense components to *** validate the model,42 sets of data collected from 6 independent literature sources were compared with the predictions of the *** the gas velocities were below 3.2 times the minimum gas velocity,the predictions were consistent with experimental *** study has shed new light on the mechanisms of particle segregation in binary fluidized systems and provides a theoretical foundation for designing and manipulating gas-solid fluidized reactors.

关键词： Particle segregation Binary mixture Bubbling fluidization Geldart B particles Two-phase theory

Dissolvable temporary barrier:a novel paradigm for flexible hydrogel patterning in organ-on-a-chip models

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Bio-Design and Manufacturing 2024年第2期7卷 153-166页

作者： Ding Wang Qinyu Li chenyang zhou Zhangjie Li Kangyi Lu Yijun Liu Lian Xuan Xiaolin Wang Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Ophthalmology LKS Faculty of MedicineThe University of Hong KongHong Kong 999077China Institute of Medical Robotics Shanghai Jiao Tong UniversityShanghai 200240China National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240China National Center for Translational Medicine(Shanghai)SHU Branch Shanghai UniversityShanghai 200444China

A combination of hydrogels and microfluidics allows the construction of biomimetic three-dimensional(3D)tissue models in vitro,which are also known as *** hydrogel patterningwith awell-controlled spatial distribution is typically achieved by embedding sophisticated microstructures to act as a ***,these physical barriers inevitably expose cells/tissues to a less physiologically relevant microenvironment than in vivo ***,we present a novel dissolvable temporary barrier(DTB)strategy that allows robust and flexible hydrogel patterning with great freedom of design and desirable flow stimuli for cellular *** key aspect of this approach is the patterning of a water-soluble rigid barrier as a guiding path for the hydrogel using stencil printing technology,followed by a barrier-free medium perfusion after the dissolution of the *** and multiple tissue compartments with different geometries can be established using either straight or curved DTB *** effectiveness of this strategy is further validated by generating a 3D vascular network through vasculogenesis and angiogenesis using a vascularized microtumor *** a new proof-of-concept in vasculature-on-a-chip,DTB enables seamless contact between the hydrogel and the culture medium in closed microdevices,which is an improved protocol for the fabrication ofmultiorgan ***,we expect it to serve as a promising paradigm for organ-on-a-chip devices for the development of tumor vascularization and drug evaluation in the future preclinical studies.

关键词： Dissolvable temporary barrier Hydrogel patterning Microfluidics Organ-on-a-chip Vascularization

In situ injectable hydrogel encapsulating Mn/NO-based immune nano-activator for prevention of postoperative tumor recurrence

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Asian Journal of Pharmaceutical Sciences 2024年第2期19卷 102-119页

作者： Shengnan Huang chenyang zhou Chengzhi Song Xiali Zhu Mingsan Miao Chunming Li Shaofeng Duan Yurong Hu Academy of Chinese Medical Sciences Henan University of Chinese MedicineZhengzhou 450046China School of Pharmaceutical Sciences Henan Key Laboratory of Targeting Therapy and Diagnosis for Critical DiseasesZhengzhou UniversityZhengzhou 450001China Center for Quantitative Biology Peking UniversityBeijing 100871China School of Pharmaceutical Sciences Henan University of Chinese MedicineZhengzhou 450046China Department of Pharmacy Chongqing University Cancer HospitalChongqing 400030China School of Pharmaceutical Sciences Henan UniversityZhengzhou 450046China

Postoperative tumor recurrence remains a predominant cause of treatment failure. In this study, we developed an in situ injectable hydrogel, termed MPB-NO@DOX + ATRA gel, which was locally formed within the tumor resection cavity. The MPB-NO@DOX + ATRA gel was fabricated by mixing a thrombin solution, a fibrinogen solution containing all-trans retinoic acid (ATRA), and a Mn/NO-based immune nano-activator termed MPB-NO@DOX. ATRA promoted the differentiation of cancer stem cells, inhibited cancer cell migration, and affected the polarization of tumor-associated macrophages. The outer MnO2 shell disintegrated due to its reaction with glutathione and hydrogen peroxide in the cytoplasm to release Mn2+ and produce O2, resulting in the release of doxorubicin (DOX). The released DOX entered the nucleus and destroyed DNA, and the fragmented DNA cooperated with Mn2+ to activate the cGAS-STING pathway and stimulate an anti-tumor immune response. In addition, when MPB-NO@DOX was exposed to 808 nm laser irradiation, the Fe-NO bond was broken to release NO, which downregulated the expression of PD-L1 on the surface of tumor cells and reversed the immunosuppressive tumor microenvironment. In conclusion, the MPB-NO@DOX + ATRA gel exhibited excellent anti-tumor efficacy. The results of this study demonstrated the great potential of in situ injectable hydrogels in preventing postoperative tumor recurrence.

关键词： Post-sur gical tumor recurrence In situl hydrogel Immunotherapy Tumor micr oenvir onment Manganese(Ⅱ) Nitic oxide

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血管化类器官芯片构建的研究进展

中华创伤杂志 2024年第1期40卷 48-56页

作者：李彰杰周晨阳王晓林上海交通大学电子信息与电气工程学院微纳电子学系上海200240 上海交通大学医疗机器人研究院上海200240

近年来,微加工技术和组织工程学的进展推动了一种新型药物筛选和疾病建模平台的发展,即类器官芯片。这一平台结合类器官和器官芯片技术,成为人体器官体外建模的有潜力的方案。类器官芯片利用微流体装置模拟特定器官的生理环境,提供更动... 详细信息

近年来,微加工技术和组织工程学的进展推动了一种新型药物筛选和疾病建模平台的发展,即类器官芯片。这一平台结合类器官和器官芯片技术,成为人体器官体外建模的有潜力的方案。类器官芯片利用微流体装置模拟特定器官的生理环境,提供更动态和灵活的微环境,可模拟更完整的人体生物学。然而,缺乏功能性血管一直是该技术面临的主要挑战之一。血管化对于类器官的长期培养和体外建模至关重要,对于药物研发和个性化医疗方案也具有重要意义。笔者从体外构建血管化模型方法和类器官血管化的策略两方面就血管化类器官芯片构建的研究进展进行综述,为构建功能完善的血管化类器官芯片提供参考。

关键词：类器官新生血管化,生理性多能干细胞微流控芯片

农业保险的增产减排效应研究:能否兼顾低碳发展

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金融理论与实践 2024年第3期 106-118页

作者：周晨阳张凌宇韦宏耀浙江工商大学泰隆金融学院浙江杭州310018 浙江工商大学金融学院浙江杭州310018

农业保险作为一种有效的风险保障机制,不仅具有分散经营风险的作用,更是绿色发展的重要抓手。基于2008—2021年中国31个地区(不含港澳台地区)的面板数据,研究农业保险的增产减排效应是否可以提升碳生产率。研究发现:农业保险发展水平的... 详细信息

农业保险作为一种有效的风险保障机制,不仅具有分散经营风险的作用,更是绿色发展的重要抓手。基于2008—2021年中国31个地区(不含港澳台地区)的面板数据,研究农业保险的增产减排效应是否可以提升碳生产率。研究发现:农业保险发展水平的提高可以显著提升农业碳生产率,地区农业保险发展水平每提高一个标准差,农业碳生产率可提高0.1108万元/吨。农业保险影响农业碳生产率的主要渠道是农业技术进步,农业产业集聚渠道并未得到检验。进一步分析发现,农业保险对碳生产率的影响存在区域、政策异质性以及空间溢出效应。研究结论丰富完善了我国农业保险制度体系和强化农业保险环境效益的相关研究。

关键词：农业保险农业碳生产率空间溢出效应农业技术进步

Short-term load forecasting model based on gated recurrent unit and multi-head attention

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The Journal of China Universities of Posts and Telecommunications 2023年第3期30卷 25-31页

作者： Li Hao Zhang Linghua Tong Cheng zhou chenyang School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing 210003China

Short-term load forecasting(STLF)plays a crucial role in the smart ***,it is challenging to capture the long-time dependence and the nonlinear relationship due to the comprehensive fluctuations of the electrical *** this paper,an STLF model based on gated recurrent unit and multi-head attention(GRU-MA)is proposed to address the aforementioned *** proposed model accommodates the time series and nonlinear relationship of load data through gated recurrent unit(GRU)and exploits multi-head attention(MA)to learn the decisive features and long-term ***,the proposed model is compared with the support vector regression(SVR)model,the recurrent neural network and multi-head attention(RNN-MA)model,the long short-term memory and multi-head attention(LSTM-MA)model,the GRU model,and the temporal convolutional network(TCN)model using the public dataset of the Global Energy Forecasting Competition 2014(GEFCOM2014).The results demonstrate that the GRU-MA model has the best prediction accuracy.

关键词： deep learning short-term load forecasting(STLF) gated recurrent unit(GRU) multi-head attention(MA)

基于优化Faster R-CNN算法的金属板材表面缺陷检测

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制造技术与机床 2024年第1期 171-178页

作者：孔思曼周晨阳王家华李林孙践知北京工商大学计算机学院北京100048

传统的图像处理方法对生产过程中各种金属板材表面缺陷检测效率低,难以满足工业生产的需求。为了提高金属板材表面缺陷检测的精度,文章提出了一种基于优化Faster R-CNN算法的金属板材表面缺陷检测方法,以残差网络ResNet50作为主干特征... 详细信息

传统的图像处理方法对生产过程中各种金属板材表面缺陷检测效率低,难以满足工业生产的需求。为了提高金属板材表面缺陷检测的精度,文章提出了一种基于优化Faster R-CNN算法的金属板材表面缺陷检测方法,以残差网络ResNet50作为主干特征提取网络。首先,融合特征金字塔网络和可变形卷积网络以提高对小目标和不规则性缺陷的检测能力。然后,采用RoI Align和K-means++聚类算法对候选框进行优化,实现缺陷的精准定位。最后,将提出的模型运用在NEU-DET数据集中进行多次实验。实验结果表明,优化后的Faster R-CNN算法在此数据集上的mAP为78.7%,与原始网络相比提高了7.7%,并且其检测性能优于SSD、YOLOv5s和YOLOv7三类目标检测算法。

关键词：缺陷检测 Faster R-CNN 特征金字塔网络可变形卷积网络聚类算法

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双层含骨基质骨器官芯片的构建

中华创伤杂志 2024年第1期40卷 20-28页

作者：张浩周晨阳胡衍陈晓王晓林苏佳灿上海交通大学医学院附属新华医院骨科上海200092 上海大学转化医学研究院上海200444 上海交通大学电子信息与电气工程学院上海200240

目的构建双层含骨基质骨器官芯片并用于体外模拟成骨细胞和破骨细胞分化,为抗骨质疏松药物开发提供新平台。方法使用WorkSoild软件制作双层双通道骨器官芯片设计图,利用光刻技术制备浇注母版。以聚二甲基硅氧烷(PDMS)为原料,通过模具浇... 详细信息

目的构建双层含骨基质骨器官芯片并用于体外模拟成骨细胞和破骨细胞分化,为抗骨质疏松药物开发提供新平台。方法使用WorkSoild软件制作双层双通道骨器官芯片设计图,利用光刻技术制备浇注母版。以聚二甲基硅氧烷(PDMS)为原料,通过模具浇注制备芯片主体。以牛皮质骨片为间隔,分隔培养室4个通道进出口采用储液柱封闭。芯片验证实验分为成骨、破骨诱导组和成骨、破骨对照组,成骨、破骨诱导组将小鼠胚胎成骨细胞前体细胞MC3T3-E1和小鼠巨噬细胞RAW264.7分别接种于芯片上,成骨诱导14 d,破骨诱导7 d。成骨、破骨对照组为不进行诱导的MC3T3-E1细胞和RAW264.7细胞。观察指标包括:(1)芯片外观及密封性:芯片制备完成后拍照观察外观并通过密封实验观察密封性能。(2)生物相容性:MC3T3-E1细胞和RAW264.7细胞接种于芯片培养3 d及培养1、3、5 d后,分别采用钙黄绿素乙酰氧基甲酯/碘化丙啶(AM/PI)染色和细胞增殖及毒性检测试剂盒(CCK-8)实验观察细胞存活情况。(3)成骨分化情况:对成骨诱导组细胞进行碱性磷酸酶(ALP)染色、茜素红染色观察成骨细胞诱导情况。收集成骨诱导组和成骨对照组细胞RNA,qPCR检测成骨细胞标志基因Runt相关转录因子2(RUNX2)、骨钙素(OCN)、Ⅰ型胶原(COL1A1)表达情况,观察成骨细胞分化程度和成骨能力。(4)破骨分化情况:对破骨诱导组细胞进行抗酒石酸酸性磷酸酶(TRAP)染色观察破骨细胞分化情况。提取破骨诱导组和破骨对照组细胞RNA进行破骨分化基因qPCR,检测破骨细胞标志基因TRAP、组织蛋白酶K(CTSK)和树突状细胞特异性跨膜蛋白(DC-STAMP)表达水平。结果双层含骨基质骨器官芯片大小为3 cm×3 cm,整体透光,芯片系统结构对接紧凑,无渗液。钙黄绿素AM/PI染色结果显示,MC3T3-E1细胞和RAW264.7细胞培养3 d后,呈红色荧光死细胞极少。CCK-8实验结果显示,MC3T3-E1细胞和RAW264.7细胞培养5 d内,细胞活力均在90%以上,表明芯片生物相容性好,细胞可以正常存活并增殖。ALP染色和茜素红染色结果显示,成骨诱导14 d,成骨诱导组MC3T3-E1细胞成功分化为成骨细胞并产生钙化结节。qPCR结果显示,成骨诱导组MC3T3-E1细胞的RUNX2相对表达量为4.98±0.74,显著高于对照组的0.99±0.03(P<0.01);MC3T3-E1细胞的OCN相对表达量为7.98±0.76,显著高于对照组的1.00±0.06(P<0.01);MC3T3-E1细胞的COL1A1相对表达量为7.07±0.56,显著高于对照组的0.97±0.03(P<0.01)。TRAP染色结果显示,破骨诱导7 d,破骨诱导组RAW264.7细胞形成巨大的多核破骨细胞,破骨细胞表达大量TRAP蛋白。qPCR检测结果显示,破骨诱导组RAW264.7细胞的TRAP相对表达量为3.35±0.37,显著高于对照组的1.01±0.06(P<0.01);RAW264.7细胞的CTSK相对表达量为3.46±0.79,显著高于对照组的1.01±0.05(P<0.01);RAW264.7细胞的DC-STAMP相对表达量为1.92±0.12,显著高于对照组的0.98±0.08(P<0.01)。结论双层含骨基质骨器官芯片结构紧凑,可长期体外培养,生物相容性好,可进行成骨和破骨细胞分化诱导,有望为骨质疏松机制探究和药物筛选提供新的研究平台。

关键词：骨质疏松类器官骨重建成骨细胞破骨细胞器官芯片

CWoT-Share: Context-Based Web of Things Resource Sharing in Blockchain Environment

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Computers, Materials & Continua 2022年第9期72卷 5079-5098页

作者： Yangqun Li Jin Qi Lijuan Min Hongzhi Yang chenyang zhou Bonan Jin School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China Jiangsu Key Laboratory of Broadband Wireless Communication and Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China Information VIII University of WürzburgWürzburg97074Germany

Web of Things(WoT)resources are not only numerous,but also have a wide range of applications and *** centralized WoT resource sharing mechanism lacks flexibility and scalability,and hence cannot satisfy requirement of distributed resource sharing in large-scale *** response to this problem,a trusted and secure mechanism for WoT resources sharing based on context and blockchain(CWoT-Share)was ***,the mechanism can respond quickly to the changes of the application environment by dynamically determining resource access control rules according to the ***,the flexible resource charging strategies,which reduced the fees paid by the users who shared more resources and increased the fees paid by users who frequently used resources maliciously,were used to fulfill efficient sharing of WoT ***,the charging strategies also achieve load balancing by dynamic selection of WoT ***,the open source blockchain platform Ethereum was used for the simulation and the simulation results show that CWoT-Share can flexibly adapt to the application environment and dynamically adjust strategies of resource access control and resource charging.

关键词： Web of things resource sharing smart contract context billing strategy