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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins

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Neural Regeneration Research 2025年第1期20卷 242-252页

作者： Daiyu Hu Yuanqing Cao Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong Lai Zhengliang Gao Fundamental Research Center Shanghai Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center)School of MedicineTongji UniversityShanghaiChina institute of Geriatrics(Shanghai University) Affiliated Nantong Hospital of Shanghai University(The Sixth People’s Hospital of Nantong)Shanghai University School of MedicineNantongJiangsu ProvinceChina Shanghai Engineering Research Center of Organ Repair Shanghai University School of MedicineShanghaiChina Key Laboratory of Arrhythmias Ministry of EducationShanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina

Human brain development is a complex process,and animal models often have significant *** address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and *** enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid *** involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid *** cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology *** a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental *** organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature *** exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic *** convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies.

关键词： cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells neurogenesis neurotoxicology organoids stem cells

预应力CFRP板加固钢板受拉疲劳性能试验研究

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西南交通大学学报 2009年第6期44卷 823-829页

作者：叶华文 KONIG Christian UMMENHOFER Thomas 强士中西南交通大学土木工程学院四川成都610031 institute for rehabilitation of buildings and structures Technical University of Braunschweig Braunschweig 38106 Germany

为较好地预测预应力碳纤维材料(CFRP)板加固钢结构的疲劳性能,采用考虑有效应力强度因子幅的Pairs公式,分析了粘贴预应力CFRP板加固钢板的疲劳裂纹扩展行为.通过粘贴CFRP板的含中心孔的预制裂纹钢板的疲劳试验,分析了应力比、CFRP板刚... 详细信息

为较好地预测预应力碳纤维材料(CFRP)板加固钢结构的疲劳性能,采用考虑有效应力强度因子幅的Pairs公式,分析了粘贴预应力CFRP板加固钢板的疲劳裂纹扩展行为.通过粘贴CFRP板的含中心孔的预制裂纹钢板的疲劳试验,分析了应力比、CFRP板刚度、预应力及粘结胶性能等因素对疲劳裂纹扩展的影响.试验结果表明:加固后结构的疲劳寿命提高16倍以上,疲劳寿命的理论分析结果偏于保守;预应力是疲劳寿命的主要影响因素,而CFRP板和粘结胶性能的影响有限;应力比对疲劳寿命的影响很大,因此,对交通荷载的正确预估是加固能否取得成功的基础.

关键词：钢结构预应力CFRP板疲劳应力比

Comparative Analysis of Reaction to Fire and Flammability of Hemp Shives Insulation Boards with Incorporated Microencapsulated Phase Change Materials

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Journal of Renewable Materials 2024年第3期12卷 603-613页

作者： Inga Zotova Edgars Kirilovs Laura Ziemele institute of Architecture and Design Riga Technical UniversityRigaLV-1048Latvia Forest and Wood Products Research and Development institute JelgavaLV-3001Latvia

Nowadays buildings contain innovative materials,materials from local resources,production surpluses and rapidly renewable natural *** Change Materials(PCM)are one such group of novel materials which reduce building energy *** the wider availability of microencapsulated PCM,there is an opportunity to develop a new type of insulating materials,combinate PCM with traditional insulation materials for latent heat energy *** materials are typically flammable and are located on the interior wall finishing yet there has been no detailed assessment of their fire *** this research work prototypes of low-density insulating boards for indoor spaces from hemp shives using carbamide resin binder and cold pressing were ***-scale cone calorimeter tests were conducted to evaluate fire risk,with a focus on assessing material flammability properties and the influence of PCM on the *** this research,the amount of smoke,heat release rate,effective heat of combustion,specific extinction coefficient,mass loss,carbon dioxide yield,specific loss factor,ignition time of hemp straws samples and samples of hemp straws with 10%and without PCM admixture were *** is a risk of flammability for PCM and their fire reaction has not been evaluated when incorporating PCM into interior wall finishing *** obtained results can be used by designers to balance the potential energy savings of using PCM with a more complete understanding and predictability of the associated fire risk when using the proposed *** also allows for appropriate risk mitigation strategies.

关键词： Encapsuled phase change material renewable resources reaction to fire flammability

Constructing a biofunctionalized 3D-printed gelatin/sodium alginate/chitosan tri-polymer complex scaffold with improvised biological andmechanical properties for bone-tissue engineering

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Bio-Design and Manufacturing 2024年第1期7卷 57-73页

作者： Amit Kumar Singh Krishna Pramanik Amit Biswas Centre of Excellence in Tissue Engineering Department of Biotechnology and Medical EngineeringNational Institute of TechnologyRourkela 769008India

Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering *** present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue *** experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and *** resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3D)*** studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural *** scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue *** tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of *** enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue *** vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold *** addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3D structures,demonstrating its pote

关键词： Scaffold Biomaterial Sodium alginate Chitosan Gelatin 3D printing Tissue engineering

Influence of BPPV and Meniere's Disease on Cognitive Abilities: A Questionnaire-Based Study

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Journal of Otology 2024年第1期19卷 10-18页

作者： Rohit Bhattacharyya Animesh Barman Freddy Antony All India institute of Speech and Hearing MysoreMysuruIndia

The vestibular system connects the inner ear to the midbrain and subcortical structures and can affect cognition. Patients with vertigo often experience cognitive symptoms such as attention deficits, memory problems, and spatial perception difficulties. This study aimed to explore the cognitive impairments associated with Benign paroxysmal positional vertigo(BPPV) and Meniere's Disease(MD). A non-experimental group comparison design was used with 107 participants divided into three groups: Group I(clinically normal), Group II(BPPV), and Group III(MD). Participants completed a questionnaire with 10 cognition-related questions, and their responses were scored. The data were found to be non-normally distributed. The analysis revealed a significant difference in scores between Group I and both Group II and Group III. Chi-square tests showed that the responses to cognition-related questions varied among the groups, with Group II exhibiting more cognitive problems. Associated conditions like hypertension, diabetes, and hearing loss did not significantly influence the responses within each group. This study suggests a significant relationship between cognitive problems and patients with BPPV and MD. However, there was no association found between the cognitive problems experienced in BPPV and MD patients. These findings align with previous research indicating that vestibular disorders can lead to deficits in spatial memory, attention, and other cognitive functions. By understanding the link between cognition and vestibular disorders, we can improve diagnosis and rehabilitation services to enhance the quality of life for these patients.

关键词： BPPV Meniere's disease Cognition Questionnaire

Assessing the influence of jet-grouting underpinning on the nearby buildings

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第2期6卷 105-112页

作者： Aleksandra Chepurnova Research institute of Bases and Underground structures(NIIOSP)

This paper focuses on the underpinning-induced ground movement due to jet-grouting. Jet-grouting technique can cause distortions as a result of an inaccurate processing sequence and/or errors made at different stages of work execution. The aim of this paper is to determine the minimum value of such movement on the basis of the findings obtained at two similar construction sites located in the Historical Center of Moscow, considering that the maximum value is usually unpredictable. Numerical simulation of the process of soil eroding agrees well with the observational data at the current stage. It was found that the minimum value of deformations （only settlement was considered in this study） due to jetgrouting is no less than 2-3 mm. By contrast, the negative scenario of deformation due to foundation underpinning is clearly demonstrated. Also, this paper provides some general solutions for excavation supporting system as well as for underpinning design.

关键词： Geotechnical analyses Jet-grouting Monitoring Soilcrete element Technological settlement Underpinning design

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预应力CFRP板加固钢梁抗弯疲劳试验研究

公路交通科技 2009年第12期26卷 50-55页

作者：叶华文 T. Ummenhofer 强士中西南交通大学土木工程学院四川成都610031 institute for rehabilitation of buildings and structures Technical University of Braunschweig

首先,采用修正的Pairs公式分析粘贴预应力CFRP板加固的钢构件的疲劳裂纹扩展行为。然后通过粘贴CFRP板的预制裂纹钢梁4点弯曲进行疲劳试验研究,最后基于阻止裂纹扩展的角度提出一种初步估计加固所需预应力大小的简化计算和设计方法。结... 详细信息

首先,采用修正的Pairs公式分析粘贴预应力CFRP板加固的钢构件的疲劳裂纹扩展行为。然后通过粘贴CFRP板的预制裂纹钢梁4点弯曲进行疲劳试验研究,最后基于阻止裂纹扩展的角度提出一种初步估计加固所需预应力大小的简化计算和设计方法。结果表明,粘贴预应力CFRP板对钢梁疲劳寿命的影响很大,与预制裂纹阶段比寿命提高最高可达10倍以上。不同的预制裂纹,同样的加固措施效果差别可达10倍。采用后张法施加预应力效果很好,锚固装置可以实时控制有效预应力,且预应力损失很小。

关键词：桥梁工程加固疲劳试验预应力CFRP板预应力损失

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预应力CFRP板加固钢板受拉试验研究

铁道建筑 2011年第5期51卷 123-127页

作者：叶华文 T.Ummenhofer 强士中西南交通大学土木工程学院成都610031 institute for rehabilitation of buildings and structures Technical University of Braunschweig

文章对预应力CFRP板双面加固钢板的轴心受拉静力行为进行了试验研究,首先采用一维线弹性理论和三维空间单元有限元模型分析预应力CFRP板双面加固钢板的轴心受拉应力分布,然后对粘贴不同预应力水平CFRP板的加固试件进行轴心受拉试验。结... 详细信息

文章对预应力CFRP板双面加固钢板的轴心受拉静力行为进行了试验研究,首先采用一维线弹性理论和三维空间单元有限元模型分析预应力CFRP板双面加固钢板的轴心受拉应力分布,然后对粘贴不同预应力水平CFRP板的加固试件进行轴心受拉试验。结果表明:施加机械锚固装置后,钢板应力水平有很大降低,承载能力相应有很大提高,但刚度提高不大,而且机械锚固装置对保持高承载能力是必须的,应力分布理论值与试验值吻合得很好。试验中还观察到CFRP板高应力条件下很小的蠕变和预应力偏心作用所导致的弯曲应力。短期预应力损失主要由弹性压缩产生,循环荷载下的预应力损失很小。因此总预应力损失可简化计算为短期损失乘以一个安全系数。

关键词：钢结构预应力CFRP板加固钢板预应力损失

A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM

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Defence Technology（防务技术） 2024年第3期33卷 463-474页

作者： Yili Wang Changsheng Li Xiaofeng Wang Nanjing University of Science and Technology Nanjing 210094JiangsuChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of *** address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent *** leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration *** analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,*** model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target *** maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed ***,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves.

关键词： Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion