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Evaluation of damage to trabecular bone of the osteoporotic human acetabulum at small strains using nonlinear micro-finite element analyses

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Chinese Medical Journal 2009年第17期122卷 2041-2047页

作者： DING hai zhu zhen-an DAI Ke-rong Department of Orthopaedics Ninth People's Hospital ShanghaiJiao Tong University School of Medicine Shanghai 200011 China

Background With advance of age, alterations in bone quality, quantity and microarchitecture render osteoporotic trabecular bone become more sensitive to local failure. The aims of the present study were to clarify the extent to which the distribution of tissue-level stresses and strains was affected by structural changes and the extent to which osteoporotic acetabular trabecular bone was damaged at small strains. Methods Using a DAWING 4000A supercomputer, nonlinear micro-finite element （μFE） analyses were performed to calculate the tissue-level strains and stresses for each element in the trabecular bone of one osteoporotic acetabulum at small strains to quantify the tissue-level damage accumulation and mechanical properties. Results In contour plots of the tissue, maximum principal logarithmic strains, high tissue-level strains, both compressive and tensile, were observed in the osteoporotic trabecular bone at small apparent strains from 0.2% to 0.5% strain. The compressive apparent stress-strain curve showed typical nonlinear behavior and tangent modulus reduction with increasing strains. The microdamage curve suggested that microdamage began at 0.2% apparent strain in the osteoporotic trabecular bone and increased sharply, although very few microfractures occurred. The quartiles of the maximum principal logarithmic strains, minimum principal logarithmic strains and Von Mises stresses increased nonlinearly. For the inter-quartile range of the Von Mises stresses, a leap occurred at small strains ranging from 0.2% to 0.3% while microdamage commenced. Conclusions Extensive microdamage was primarily responsible for the large loss in apparent mechanical properties that occurred in the trabecular bone of the osteoporotic acetabulum at small strains. With increasing apparent strains, continuous nonlinear increments of tissue-level strains and stresses resulted in microdamage that propagated throughout the specimen with very few microfractures. Chin Med J 2009; 122（17）：

关键词： mechanical property trabecular bone nonlinear micro-finite element analysis acetabulum osteoporosis

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基于决策树的被动操作系统识别技术研究

计算机科学 2016年第8期43卷 79-83页

作者：易运晖刘海峰朱振显西安电子科技大学通信工程学院西安710071

操作系统识别是网络安全评估的关键技术之一,在网络安全威胁和风险日益加剧的形势下,其研究具有非常重要的意义。针对当前基于TCP/IP协议栈指纹库的操作系统识别技术难以辨识未知指纹所对应的操作系统的问题,提出了基于C4.5决策树模型... 详细信息

操作系统识别是网络安全评估的关键技术之一,在网络安全威胁和风险日益加剧的形势下,其研究具有非常重要的意义。针对当前基于TCP/IP协议栈指纹库的操作系统识别技术难以辨识未知指纹所对应的操作系统的问题,提出了基于C4.5决策树模型的被动操作系统识别方法,并将它与其他分类算法进行了比较。通过实验测试验证了分类方法的有效性,并对其结果进行了分析。

关键词：操作系统识别 TCP/IP协议栈指纹决策树有效性

Liver as a new target organ in Alzheimer's disease:insight from cholesterol metabolism and its role in amyloid-beta clearance

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Neural Regeneration Research 2025年第3期20卷 695-714页

作者： Beibei Wu Yuqing Liu Hongli Li Lemei zhu Lingfeng Zeng zhen Zhang Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina Yangsheng College of Traditional Chinese Medicine Guizhou University of Traditional Chinese MedicineGuiyangGuizhou ProvinceChina Qinhuangdao Shanhaiguan Pharmaceutical Co. LtdQinhuangdaoHebei ProvinceChina National Clinical Research Center for Mental Disorder The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary *** amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs,targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease *** abnormalities are commonly observed in patients with Alzheimer's *** liver is the primary peripheral organ involved in amyloid-beta metabolism,playing a crucial role in the pathophysiology of Alzheimer's ***,impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's *** this review,we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol ***,we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.

关键词： ABCA1 Alzheimer's disease amyloid-beta apolipoprotein E cholesterol metabolism liver liver X receptor low-density lipoprotein receptor-related protein 1 peripheral clearance tauroursodeoxycholic acid

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing He zhen Wang Yuchen Wang Mengjie zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

基于多元线性回归模型的居民用电量影响因素分析

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西昌学院学报（自然科学版） 2017年第1期31卷 28-30,45页

作者：张海珍朱家明安徽财经大学金融学院安徽蚌埠233030 安徽财经大学统计与应用学院安徽蚌埠233030

随着社会和科学的不断进步,人们意识到环境能源对人类发展的重要性,节约能源是其中的一个重要措施。居民用电量与多种因素有关。为了研究各个影响因素对居民用电量影响程度的大小,以蚌埠市为例,首先从影响电量的供给、需求和外部因素角... 详细信息

随着社会和科学的不断进步,人们意识到环境能源对人类发展的重要性,节约能源是其中的一个重要措施。居民用电量与多种因素有关。为了研究各个影响因素对居民用电量影响程度的大小,以蚌埠市为例,首先从影响电量的供给、需求和外部因素角度分别选取了收入、价格、人口、气温及居住面积等五个因素作为分析指标,然后在EVIEWS建立蚌埠市居民用电量与以上5个因素的多元线性回归模型,用以研究各个影响因素对居民用电量的影响程度大小。通过EVIEWS对回归结果的分析得到如下结论:当前影响蚌埠市居民用电量的最主要因素取决于人口数量和人均居住面积,并提出节约用电的相关建议。

关键词：居民用电量影响因素多元线性回归模型 EVIEWS

Prediction and stratification for the surgical adverse events after minimally invasive esophagectomy:A two-center retrospective study

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World Journal of Gastroenterology 2025年第3期31卷 50-61页

作者： Qi-Hong Zhong Jiang-Shan Huang Fei-Long Guo Jing-Yu Wu Mao-Xiu Yuan Jia-Fu zhu Wen-Wei Lin Sui Chen zhen-Yang Zhang Jiang-Bo Lin Department of Thoracic Surgery Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina The Graduate School Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Thoracic Surgery Affiliated Hospital of Jinggangshan UniversityJi’an 343000Jiangxi ProvinceChina

BACKGROUND Minimally invasive esophagectomy(MIE)is a widely accepted treatment for esophageal cancer,yet it is associated with a significant risk of surgical adverse events(SAEs),which can compromise patient recovery and long-term *** preoperative identification of high-risk patients is critical for improving *** To establish and validate a risk prediction and stratification model for the risk of SAEs in patients with *** This retrospective study included 747 patients who underwent MIE at two centers from January 2019 to February *** were separated into a train set(n=549)and a validation set(n=198).After screening by least absolute shrinkage and selection operator regression,multivariate logistic regression analyzed clinical and intraoperative variables to identify independent risk factors for SAEs.A risk stratification model was constructed and validated to predict the probability of *** SAEs occurred in 10.2%of patients in train set and 13.6%in the validation *** with SAE had significantly higher complication rate and a longer hospital stay after *** key independent risk factors identified included chronic obstructive pulmonary disease,a history of alcohol consumption,low forced expiratory volume in the first second,and low albumin *** stratification model has excellent prediction accuracy,with an area under the curve of 0.889 for the training set and an area under the curve of 0.793 for the validation *** The developed risk stratification model effectively predicts the risk of SAEs in patients undergoing MIE,facilitating targeted preoperative interventions and improving perioperative management.

关键词： Surgical adverse events Minimally invasive esophagectomy Esophageal cancer Stratification model Perioperative management

Embedded-Soliton and Complex Wave Excitations of (3+1)-Dimensional Burgers System

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Communications in Theoretical Physics 2008年第6期49卷 1425-1431页

作者： zhu hai-Ping PAN zhen-Huan Chun-Long College of Mathematics and Physics Lishui University Lishui 323000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

Starting from the extended mapping approach and a linear variable separation method, we find new families of variable separation solutions with some arbitrary functions for the （3＋1）-dimensionM Burgers system. Then based on the derived exact solutions, some novel and interesting localized coherent excitations such as embedded-solitons, taper-like soliton, complex wave excitations in the periodic wave background are revealed by introducing appropriate boundary conditions and/or initial qualifications. The evolutional properties of the complex wave excitations are briefly investigated.

关键词： extended mapping approach (3+1)-dimensional Burgers system embed-soliton taper-like soliton complex wave excitation

Multiphase Flow and Thermo-Mechanical Behaviors of Solidifying Shell in Continuous Casting Mold

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Journal of Iron and Steel Research International 2013年第3期20卷 6-17页

作者： zhu Miao-yong CAI Zhao-zhen YU hai-qi School of Materials and Metallurgy Northeastern University

The metallurgical phenomena occurring in the continuous casting mold have a significant influence on the performance and the quality of steel *** multiphase flow phenomena of molten steel,steel/slag interface and gas bubbles in the slab continuous casting mold were described by numerical simulation,and the effect of electromagnetic brake（EMBR） and argon gas blowing on the process were *** relationship between wavy fluctuation height near meniscus and the level fluctuation index F,which reflects the situation of mold flux entrapment,was ***,based on a microsegregation model of solute elements in mushy zone with δ/γ transformation and a thermo-mechanical coupling finite element model of shell solidification,the thermal and mechanical behaviors of solidifying shell including the dynamic distribution laws of air gap and mold flux,temperature and stress of shell in slab continuous casting mold were described.

关键词： continuous casting mold multiphase flow heat transfer solidification numerical simulation

Effects of process parameters on fragment and refinement of millimeter- grade coarse grains for 316LN steel during hot cogging

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Journal of Iron and Steel Research International 2017年第5期24卷 529-535页

作者： Da-shan Sui hai-ming Zhang Hong-yang zhu Zhe zhu zhen-shan Cui National Die & Mold CAD Engineering Research Center Shanghai Jiao Tong University Shanghai 200030 China Shanghai Heavy Machinery Plant Shanghai 200245 China

The heterogeneous mixed-grain microstructure is a common defect for the heavy forging of 316LN austenitie stainless steel. Isothermal compression experiments were performed on a Gleeble-3500 thermo-mechanical simulator to investigate the effect of process parameters on the fragment and re- finement of millimeter-grade coarse grains （MCGs） during hot cogging. The experimental results in- dicate that the stress of MCG specimens is much larger than that of fine grain （FG） ones at 1150 ℃, while the stress difference between MCG and FG samples became smaller at 1200 ℃. Moreover, the MCGs can be well fragmented and refined under the condition of temperature of 1200 ℃, strain rate of 0.01 s-1 , and reduction rate of 50%. Meanwhile, numerical simulations were conducted to study the influences of temperature, strain and strain rate on microstructure evolution. The results of ex- periments and simulations comprehensively demonstrate that the MCG results in the increase of de- formation resistance and incompatibility of deformation, and it can be fragmented and refined at 1200 ℃ so that the plastic deformation energy decreases remarkably with the increase of temperature from 1 150 to 1200 ℃.

关键词： 316LN steel Hot deformation Coarse grain Microstrueture evolution Numerical simulation