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Design of a High Precision Multichannel 3D Bioprinter

Chinese Journal of Mechanical Engineering 2023年第6期36卷 127-146页

作者： jintao li Bin Zhang Yichen Luo Huayong Yang State Key Laboratory of Fluid Power Transmission and Control School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China

Three-dimensional(3D)printing technology is expected to solve the organ shortage problem.However,owing to the accuracy limitations,it is difficult for the current bioprinting technology to achieve an accurate control of the spatial position and distribution of a single cell or single component droplet.In this study,to accurately achieve the directional deposition of different cells and biological materials in the spatial position for the construction of large transplantable tissues and organs,a high-precision multichannel 3D bioprinter with submicron-level motion accuracy is designed,and concurrent and synergistic printing methods are proposed.Based on the high-precision motion characteristics of the gantry structure and the requirements of concurrent and synergistic printing,a 3D bioprint-ing system with a set of 6 channels is designed to achieve six-in-one printing.Based on the Visual C++environ-ment,a control system software that integrates the programmable multi-axis controller(PMAC)motion,pneumatic,and temperature control subsystems was developed and designed.Finally,based on measurements and experiments,the 3D bioprinter and its control system was verified to fulfil the requirements of multichannel,concurrent,and syn-ergistic printing with submicron-level motion accuracy,significantly shortening the printing time and improving the printing efficiency.This study not only provides an equipment basis for printing complex heterogeneous tissue structures,but also improves the flexibility and functionality of bioprinting,and ultimately makes the construction of complex multicellular tissues or organs possible.

关键词： 3D bioprinting High precision Concurrent and synergistic printing Multichannel Control system Six-in-one printing

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Spatial location differentiation and development decision optimization of characteristic villages and towns in China

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Geography and Sustainability 2022年第1期3卷 21-31页

作者： jintao li Yuling Gong Institute of Governance Shandong UniversityQingdao 266200China School of Politics and Public Administration Shandong UniversityQingdao 266200China Centre for Quality of life and Public Policy Research Shandong UniversityQingdao 266237China School of Environmental Science and Engineering Shandong UniversityQingdao 266200China Institute of Eco-Environmental Forensics Shandong UniversityQingdao 266200China

Due to rapid urbanization and industrialization,the gap between urban and rural development has gradually increased.Rural development problems have been a significant topic of discussion,and are related to people’s livelihoods.This article built a point-axis-region location driving system to analyze the spatial location differentiation of characteristic villages and towns(CVTS)using the kernel density model,and explored the mechanism of location driving factors with a geographical detector model.The results show that vegetables and fruits are the main types of products in CVTS.They account for 27.60%and 34.68%of all types of products,and occur mainly in the east and central regions of China.Moreover,all point-axis-region driving factors have a significant influence on grain crops.The mean values of driving forces of vegetables and fruits are larger than other types of CVTS,and their values are 0.12 and 0.11.The average driving forces on all CVTS in the northeast are higher than those in other regions,especially the driving forces of vegetables and medicinal crops(0.24 and 0.18,respectively).Finally,we proposed that the Chinese government should employ engineering technology,invest on road networks,e-commerce and blockchain technology to optimize the point-axis-region location advantages,to promote the sustainable development of CVTS.The detection of driving mechanisms on spatial location differentiation of CVTS has important research value for location theory and rural region systems research.

关键词： Characteristic villages and towns Point-axis-region driving system Spatial driving factors Decision optimization Kernel density

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An Overview of Organs-on-Chips Based on Deep Learning

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Research 2022年第2期2022卷 141-160页

作者： jintao li Jie Chen Hua Bai Haiwei Wang Shiping Hao Yang Ding Bo Peng Jing Zhang lin li Wei Huang Frontiers Science Center for Flexible Eletronrics Xi'an Institu te of Flexible Electronics(IFE)and Xr'an Institute of Biomedical Materials EngineeringNorthwesterm Polytechnical UniversityXi'an 710072China Key Laboratory of Ietlieant Computing and Signal Processing of Minsry of Educaton School of Electronics and Information EngineeringAnhui UriversityHefei 230601China 38th Research Institute of China Eilectronics Technology Grouep Corporation Hiefei 230088 China Collge of Biomedical Engimeering Sichuan UntiversityChengdu 610065China Key Laboratory of Flexible Elecronics(KLOFE)and Institute of Advanced Materials(IAM)Nanjing Tech University(NanjingTech)J Nanjing 211800 China

Microfluidic-based organs-on-chips(OoCs)are a rapidly developing technology in biomedical and chemical research and have emerged as one of the most advanced and promising in vitro models.The miniaturization,stimulated tissue mechanical forces.and microenvironment of OoCs offer unique properties for biomedical applications.However,the large amount of data generated by the high parallelization of OoC systems has grown far beyond the scope of manual analysis by researchers with biomedical backgrounds.Deep learning,an emerging area of research in the field of machine learning,can automatically mine the inherent characteristics and laws of"big data"and has achieved remarkable applications in computer vision,speech recognition,and natural language processing.The integration of deep learning in OoCs is an emerging field that holds enormous potential for drug development,disease modeling,and personalized medicine.This review bricfly describes the basic concepts and mechanisms of microfluidics and deep learning and summarizes their successful integration.We then analyze thecombination of OoCs and deep learning for image digitization,data analysis,and automation.Finally,the problems faced in current applications are discussed,and future perspectives and suggestions are provided to further strengthen this integration.

关键词： Deep holds beyond

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Automatic extraction and reconstruction of a 3D wireframe of an indoor scene from semantic point clouds

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International Journal of Digital Earth 2023年第1期16卷 3239-3267页

作者： Junyi Wei Hangbin Wu Han Yue Shoujun Jia jintao li Chun liu College of Surveying and Geo-informatics Tongji UniversityShanghaiPeople's Republic of China

Accurate indoor 3D models are essential for building administration and applications in digital city construction and operation.Developing an automatic and accurate method to reconstruct an indoor model with semantics is a challenge in complex indoor environments.Our method focuses on the permanent structure based on a weak Manhattan world assumption,and we propose a pipeline to reconstruct indoor models.First,the proposed method extracts boundary primitives from semantic point clouds,such as floors,walls,ceilings,windows,and doors.The primitives of the building boundary,are aligned to generate the boundaries of the indoor scene,which contains the structure of the horizontal plane and height change in the vertical direction.Then,an optimization algorithm is applied to optimize the geometric relationships among all features based on their categories after the classification process.The heights of feature points are captured and optimized according to their neighborhoods.Finally,a 3D wireframe model of the indoor scene is reconstructed based on the 3D feature information.Experiments on three different datasets demonstrate that the proposed method can be used to effectively reconstruct 3D wireframe models of indoor scenes with high accuracy.

关键词： Point cloud primitive extraction semantic optimization indoor model reconstruction

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Amplitude of sensory nerve action potential in early stage diabetic peripheral neuropathy:an analysis of 500 cases

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Neural Regeneration Research 2014年第14期9卷 1389-1394页

作者： Yunqian Zhang jintao li Tingjuan Wang Jianlin Wang Department of Neurology the Fourth Affiliated Hospital of Kunming Medical University Neuroscience Institute Kunming Medical University

Early diagnosis of diabetic peripheral neuropathy is important for the successful treatment of diabetes mellitus. In the present study, we recruited 500 diabetic patients from the Fourth Affiliated Hospital of Kunming Medical University in China from June 2008 to September 2013：221 cases showed symptoms of peripheral neuropathy （symptomatic group） and 279 cases had no symptoms of peripheral impairment （asymptomatic group）. One hundred healthy control subjects were also recruited. Nerve conduction studies revealed that distal motor latency was longer, sensory nerve conduction velocity was slower, and sensory nerve action potential and amplitude of compound muscle action potential were significantly lower in the median, ulnar, posterior tibial and common peroneal nerve in the diabetic groups compared with control subjects. Moreover, the alterations were more obvious in patients with symptoms of peripheral neuropathy. Of the 500 diabetic patients, neural conduction abnormalities were detected in 358 cases （71.6%）, among which impairment of the common peroneal nerve was most prominent. Sensory nerve abnormality was more obvious than motor nerve abnormality in the diabetic groups. The amplitude of sensory nerve action potential was the most sensitive measure of peripheral neuropathy. Our results reveal that varying degrees of nerve conduction changes are present in the early, asymptomatic stage of diabetic peripheral neuropathy.

关键词： nerve regeneration peripheral nerve injury diabetic peripheral neuropathy neural con-duction electrophysiology sensory nerve motor nerve early diagnosis neural regeneration

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JNK3 involvement in nerve cell apoptosis and neurofunctional recovery after traumatic brain injury

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Neural Regeneration Research 2013年第16期8卷 1491-1499页

作者： Jiang Long li Cai jintao li Lei Zhang Haiyang Yang Tinghua Wang Department of Neurosurgery First Affiliated Hospital of Kunming Medical University Neuroscience Institute of Kunming Medical University

Increasing evidence has revealed that the activation of the JNK pathway participates In apoptosis o1 nerve cells and neurological function recovery after traumatic brain injury. However, which genes inI the JNK family are activated and their role in traumatic brain injury remain unclear. Therefore, in this study, in situ end labeling, reverse transcription-PCR and neurological function assessment were adopted to investigate the alteration of JNK1, JNK2 and JNK3 gene expression in cerebral injured rats, and their role in celt apoptosis and neurological function restoration. Results showed that JNK3 expression significantly decreased at 1 and 6 hours and 1 and 7 days post injury, but that JNK1 and JNK2 expression remained unchanged. In addition, the number of apoptotic nerve cells surrounding the injured cerebral cortex gradually reduced over time post injury. The Neurological Severity Scores gradually decreased over 1,3, 5, 14 and 28 days post injury. These findings suggested that JNK3 expression was downregulated at early stages of brain injury, which may be associated with apoptosis of nerve cells. Downregulation of JNK3 expression may promote the recovery of neurological function following traumatic brain injury.

关键词： neural regeneration JNK1 JNK2 JNK3 traumatic brain injury TdT-mediated dUTP nick endlabeling reverse transcription-PCR cell apoptosis neurological function recovery neuroregeneration

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Directional induction of dopaminergic neurons from neural stem cells using substantia nigra homogenates and basic fibroblast growth factor

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Neural Regeneration Research 2012年第7期7卷 511-516页

作者： jintao li Qi Yan Yiliu Ma Zhongtang Feng Tinghua Wang Institute of Neuroscience Kunming Medical College Kunrning 650031 Yunnan Province China Department of Minimally Invasive Neurosurgery First Hospital of Kunming Medical College Kunming 650032 Yunnan Province China

To date, complex components of available reagents have been used for directional induction of neural stem cells into dopaminergic neurons, resulting in a poor ability to repeat experiments. This study sought to investigate whether a homogenate of the substantia nigra of adult rats and/or basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons. Tyrosine hydroxylase-positive cells were observed exclusively after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor for 48 hours in vitro. However, in the groups treated with homogenate supernatant or basic fibroblast growth factor alone, tyrosine hydroxylase expression was not observed. Moreover, the content of dopamine in the culture medium of subventricular zone neurons was significantly increased at 48 hours after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor. Experimental findings indicate that the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons in the substantia nigra with the ability to secrete dopamine.

关键词： directional induction in vitro homogenate of substantia nigra basic fibroblast growth factor subventricular zone neural stem cells dopaminergic neurons

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支链氨基酸代谢在肿瘤发生发展中的作用

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遗传 2024年第6期46卷 438-451页

作者：沈院李金涛尹淼雷群英复旦大学附属肿瘤医院肿瘤研究所上海200032

支链氨基酸(branched-chain amino acids,BCAAs),包括亮氨酸、缬氨酸和异亮氨酸,在调节体内代谢平衡、维持正常生命活动中发挥着重要作用。许多研究报道了它们在肥胖、糖尿病和心血管等疾病中的代谢和功能。近些年研究表明,BCAAs代谢在... 详细信息

支链氨基酸(branched-chain amino acids,BCAAs),包括亮氨酸、缬氨酸和异亮氨酸,在调节体内代谢平衡、维持正常生命活动中发挥着重要作用。许多研究报道了它们在肥胖、糖尿病和心血管等疾病中的代谢和功能。近些年研究表明,BCAAs代谢在肿瘤发生发展中也起着重要作用。本文综述了BCAAs代谢在该方面的研究进展,包括与表观遗传调控的关系,特别是围绕肿瘤代谢重塑和代谢感知,讨论了其在肿瘤细胞和肿瘤微环境(tumor microenvironment,TME)中的作用。深入了解BCAAs代谢在肿瘤发生发展中的作用及其机制有助于为开发新的肿瘤治疗策略提供理论基础。

关键词：支链氨基酸肿瘤细胞肿瘤微环境代谢感知代谢重塑表观遗传

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Duplexer Design for Full-Duplex Based Wireless Communications

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China Communications 2016年第11期13卷 1-13页

作者： Hui Zhuang jintao li Weibiao Geng Xiaoming Dai Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services School of Computer and Communication EngineeringUniversity of Science and Technology

The full-duplex(FD) based wireless communication devices,which are capable of concurrently transmitting and receiving signals with a single frequency band,suffer from a severe self-interference(SI) due to the large power difference between the devices' own transmission and the useful signal comes from the remote transmitters. To enable the practical FD devices to be implementable,the SI power must be sufficiently suppressed to the level of background noise power,making the received signal-to-interference-plus-noise ratio(SINR) satisfy the decoding requirement. In this paper,the design and implementation of the duplexer for facilitating SI cancellation in FD based wireless communications are investigated,with a new type of duplexer(i.e. an improved directional coupler) designed for improving the spatial suppression of the SI power. Furthermore,the practical circuit boards are designed and verified for the proposed prototype,showing that the spatial suppression capability may be up to 36 d B(i.e. much higher than that attainable in the commonly designed ferrite circulator) by using the proposed design.

关键词：无线通信设备双工器全双工设计信号干扰噪声比噪声功率接收信号 SINR

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Soil respiration response to precipitation reduction in a grassland and a Mongolian pine plantation in semi-arid northeast China

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Journal of Forestry Research 2019年第5期30卷 1925-1934页

作者： Yalin Hu jintao li Shanyu Zhao Dehui Zeng College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002People’s Republic of China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Climate change is predicted to alter global precipitation regimes.However,the response of soil carbon and nitrogen cycles and soil microorganisms to precipitation reduction is poorly understood but is dependent on ecosystem type.To evaluate the impacts of reduced precipitation on soil respiration,soil inorganic nitrogen(i.e.,NH4^+–N and NO3^-–N),nitrogen mineralization,and soil microbial community composition,a precipitation manipulation experiment was initiated in a Mongolian pine plantation and a naturally restored grassland in semi-arid northeast China.Precipitation reduction led to decreases of soil respiration rates by 14 and 8%in 2014 and 2015 in the Mongolian pine plantation but no changes in the grassland.Soil inorganic nitrogen,ammonification and nitrification rate,and soil phospholipids fatty acids were not significantly changed by reduced precipitation but significantly differed between the two ecosystems and among growing seasons.Our results suggest that the impacts of precipitation reduction on soil respiration were different between the Mongolian pine plantation and the grassland,and that ecosystem type and growing season had more pronounced impacts on soil carbon and nitrogen cycles.

关键词： Precipitation reduction Soil respiration rate N mineralization Phospholipids fatty acids Semi-arid region

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