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考虑软化效应的滨海软土区基桩受力与变形特性分析

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中外公路 2024年第2期44卷 1-8页

作者：王飞闫宇焦立冬申奉歧陈璐刘建华中化学建设投资集团有限公司北京市102300 长沙理工大学公路工程教育部重点实验室湖南长沙410114

为探讨水平荷载作用下滨海软土区基桩受力与变形性能,首先根据滨海软土区基桩受荷特点建立相应的简化受力模型;其次,考虑滨海软土的软化效应,对现有的p‑y曲线模型进行修正;据此导出滨海软土区基桩挠曲微分方程,并通过传递矩阵法对其内... 详细信息

为探讨水平荷载作用下滨海软土区基桩受力与变形性能,首先根据滨海软土区基桩受荷特点建立相应的简化受力模型;其次,考虑滨海软土的软化效应,对现有的p‑y曲线模型进行修正;据此导出滨海软土区基桩挠曲微分方程,并通过传递矩阵法对其内力及位移进行求解,获得考虑软化效应的滨海软土区基桩非线性计算方法;最后,结合相关工程案例,分析软化参数、桩径和桩体弹性模量对基桩水平承载性能的影响。研究结果表明:采用传递矩阵法对软土区水平受荷桩进行受力分析精度较高,计算效率也高,可为相关工程提供参考;软化参数每增加0.3,地面处桩身水平位移分别减小24.12%和43.04%;桩径每增加0.7 m,地面处桩身水平位移分别减小62.63%和79.65%,桩体位移及内力的影响深度随桩径增大而增大;桩体弹性模量由25.5 GPa增加到36.0 GPa时,桩身变形量分别减小了6.25%和23.06%。

关键词：桩基础软土软化效应水平承载特性 p‑y曲线

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无菌鼠细菌检测方法的选择与探讨

实验动物科学 2024年第1期41卷 51-57页

作者：韩磊蔡利东李灵恩吴东王馨宇熊艳杨慧欣江苏集萃药康生物科技股份有限公司南京210061

目的比较培养法、革兰染色镜检法和16S rRNA PCR方法对无菌小鼠粪便样品细菌检测的检测性能,为无菌鼠细菌检测方法的选择提供依据。方法利用培养法、革兰染色镜检法、16S rRNA PCR方法,分别检测GF小鼠粪便、SPF小鼠粪便以及已知含菌... 详细信息

目的比较培养法、革兰染色镜检法和16S rRNA PCR方法对无菌小鼠粪便样品细菌检测的检测性能,为无菌鼠细菌检测方法的选择提供依据。方法利用培养法、革兰染色镜检法、16S rRNA PCR方法,分别检测GF小鼠粪便、SPF小鼠粪便以及已知含菌量的测试样品(无菌小鼠粪便与金黄色葡萄球菌、大肠埃希菌混合,人为制作而成),验证3种方法对无菌小鼠粪便中细菌的检测限度;并同时使用3种方法检测临床样品,对比3种检测方法的优缺点,分析3种方法在实际检测中的可行性。结果培养法、革兰染色镜检法和16S rRNA PCR方法检测灵敏度分别为102CFU/g、108CFU/g和106CFU/g,临床样品检测中阳性率均为1.36%(6/441)。结论培养法、革兰染色镜检法、16S rRNA PCR法3种检测方法各有优缺点,需要联合使用,取长补短,确保检测结果的可靠。

关键词：无菌小鼠细菌检测培养法 PCR 革兰染色镜检

Molecular movements of trehalose inside a single network enabling a rapidly-recoverable tough hydrogel

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International Journal of Smart and Nano Materials 2022年第4期13卷 575-596页

作者： Xiaowen Huang Jimin Fu Huiyan Tan yan Miu Mengda Xu Qiuhua Zhao Yujie Xie Shengtong Sun Haimin Yao lidong Zhang School of Chemistry and Molecular Engineering East China Normal UniversityShanghaiChina Department of Mechanical Engineering the Hong Kong Polytechnic UniversityHong Kong SARChina State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of ChemistryChemical Engineering and BiotechnologyCenter for Advanced Low-dimension MaterialsDonghua UniversityShanghaiChina The Hong Kong Polytechnic University Shenzhen Research Institute ShenzhenChina

It remains a challenge to achieve rapidly recoverable hydrogels by molecular hydrogen-bonding interaction because of its slow inter-action *** work for the first time reports a trehalose(Tre)-based molecular movement mechanism inside a single network of polyacrylamide(PAM)that accelerates the kinetics of hydrogenbonding interaction,and thereby endows the hydrogel with high toughness and rapid shape and mechanical *** resultant PAM@Tre hydrogel is capable of full shape recovery after 10,000 loading/unloading cycles at a strain of 500%.Even after being stretched at a strain of 2500%,it can recover to its original shape within 10 ***,the molecular movement of trehalose also endows the PAM@Tre hydrogel with fracture energy and toughness as high as~9000 J m^(-2) and~1600 kJ m^(-3),respec-tively,leading to strong resistance to both static and dynamic *** PAM@Tre hydrogel is thus believed to have enormous potentials in protection devices,bionic skin,soft actuator,and stretchable electronics.

关键词： molecular motility highly recoverable tough hydrogels puncture resistance molecular dynamics simulation

Proliferation and differentiation into endothelial cells of human bone marrow mesenchymal stem cells (MSCs) on poly DL-lactic-co-glycolic acid (PLGA) films

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Chinese Science Bulletin 2006年第11期51卷 1328-1333页

作者： YUE Huimin ZHANG Lei WANG Yunfang LIANG Feng GUAN lidong Li Shaoqing yan Fang NAN Xue BAI Cixian LIN Feng yan Yongnian PEI Xuetao Department of Stem Cell Biology Institute of Transfusion Medicine Academy of Military Medical Sciences Beijing 100850 China Research Center of Laser Rapid Forming Mechanical Department of Tsinghua University Beijing 100084 China These authors contributed equally to this work.

The functional realization is the most important problem in vascular tissue engineering. The small-caliber blood vessel substitutes are prone to thrombi, which results in functional loss of blood vessels. However, this is probably due to the imper- fection of endothelial layer in the substitutes. In this study, MSCs were seeded on a series of porous PLGA films with various porosity and pore size made by sodium chloride (NaCl) particulate leaching, and cell proliferation on each film was inspected. The film made of the 75% (w/w) particulate proportion and 30―50 μm pore size maximized the proliferation rate and was chosen as the scaffolds for the differentia- tion of MSCs into endothelial cells. The induced cells expressed endothelial cells specific Flk-1, Ⅷ factor and CD34, possessed endothelial cells specific Weible-palade (W-P) body, and had the abilities of ingesting low density lipoprotein and secreting prostacyclin (PGI2). The results show that MSCs not only have the ideal biological compatibility with the porous PLGA films, but also have the potency of dif- ferentiating into functional endothelial cells, whichshould facilitate the endothelialization in vascular tissue engineering.

关键词： MSCs PLGA 内皮细胞内皮化维管组织工程

基于TGNET软件对混空轻烃燃气管网模拟及优化

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当代化工 2024年第9期53卷 2214-2219页

作者：张书元王景刚柳朋浩亓立冬康新星严康耿金河北工程大学能源与环境工程学院河北邯郸056038

在分析L村的管网内气体流动的基础上,对混空轻烃燃气管网的实际运行状况进行研究,优化存在问题的管段,对保证混空轻烃燃气正常输送具有重要意义。利用TGNET软件,建立混空轻烃燃气管网骨架模型,提出当量长度法和粗糙度法2种方式将局部阻... 详细信息

在分析L村的管网内气体流动的基础上,对混空轻烃燃气管网的实际运行状况进行研究,优化存在问题的管段,对保证混空轻烃燃气正常输送具有重要意义。利用TGNET软件,建立混空轻烃燃气管网骨架模型,提出当量长度法和粗糙度法2种方式将局部阻力损失添加到TGNET软件中,进行稳态模拟。考虑计算精度及运行成本,选用当量长度法将局部阻力折算到管网参数中,分析整个管网的压力,并对压损较大的37、39管段采取增大管径和改变管网布置模式2种方式进行优化。结果表明:管径由DN63增大为DN75时,37、39管段压损降幅均为55%;增大为DN90时,管段的压损降幅分别为80%、81%。改变管网布置模式后,37、39管段压损降幅分别为40%、65%,优化后的管网压损均明显降低。根据L村实际情况,综合考虑,建议采用改变管网布置模式的优化方式。

关键词：管网 TGNET软件模拟压损优化

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航天用隧道管轴向低压压形成形精度控制研究

航天制造技术 2024年第4期 20-24页

作者：胡德友渠福泉梁立冬李奎侯银松闫瑾初冠南天津航天长征火箭制造有限公司天津300462 哈尔滨工业大学(威海)材料科学与工程学院威海264209

针对运载火箭的高密度发射需求,进一步提升贮箱用隧道管整体制造质量可靠性和生产效率。以航天用Φ340mm的5A03铝合金隧道管为研究对象,通过开展轴向低压压形成形波纹有限元仿真分析,探究不同内压和补料量等工艺参数对隧道管波纹型面精... 详细信息

针对运载火箭的高密度发射需求,进一步提升贮箱用隧道管整体制造质量可靠性和生产效率。以航天用Φ340mm的5A03铝合金隧道管为研究对象,通过开展轴向低压压形成形波纹有限元仿真分析,探究不同内压和补料量等工艺参数对隧道管波纹型面精度和壁厚分布影响规律。结果表明,波纹成形内压为4MPa,补料量为16.5mm时,波形精度和波高均达到设计要求,环向和轴向的波纹壁厚分布一致性较好,最大减薄率为7.09%。

关键词： 5A03铝合金轴向低压压形内压补料量减薄率

In vitro differentiation of human adipose-derived mesenchymal stem cells into endothelial-like cells

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Chinese Science Bulletin 2006年第15期51卷 1863-1868页

作者： GUAN lidong LI Shaoqing WANG Yunfang YUE Huimin LIU Daqing HE Lijuan BAI Cixian yan Fang NAN Xue SHI Shuangshuang PEI Xuetao Department of Stem Cell and Regenerative Medicine Beijing Institute of Transfusion Medicine Beijing 100850 China Stomatology Hospital the Fourth Military Medical University Xi'an 710032 China

The neovascularization of ischemic tis- sue is a crucial initial step for the functional rehabili- tation and wound healing. However, the short of seed cell candidate for the foundation of vascular network is still a big issue. Human adipose tissue derived mesenchymal stem cells (hADSCs), which possess multilineage potential, are capable of adipogenic, osteogenic, and chondrogenic differentiation. We examined whether this kind of stem cells could dif- ferentiate into endothelial-like cells and participate in blood vessel formation, and whether they could be used as an ideal cell source for therapeutic angio- genesis in ischemic diseases or vascularization of tissue constructs. The results showed that hADSCs, grown under appropriately induced conditions, dis- played characteristics similar to those of vessel en- dothelium. The differentiated cells expressed endo- thelial cell markers CD34 and vWF, and had high metabolism of acetylated low-density lipoprotein and prostacyclin. In addition, the induced cells were able to form tube-like structures when cultured on matrigel. Our data indicated that induced hADSCs could ex- hibit characteristics of endothelial cells. Therefore, these cells, as a source of human endothelial cells, may find many applications in such realms as engi- neering blood vessels, endothelial cell transplantation for myocardial regeneration, and induction of angio- genesis for treatment of regional ischemia.

关键词：脂肪组织干细胞内皮细胞组织工程

基于基因集富集分析阐释补肺健脾方干预巨噬细胞炎症反应配伍机制

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中医学报 2024年第5期39卷 1076-1081页

作者：黄丽冬关庆洲赵鹏田燕歌李康沉彭岩郭弘妍李建生河南中医药大学呼吸疾病中医药防治省部共建协同创新中心/河南省中医药防治呼吸病重点实验室河南郑州450046 河南中医药大学中医药科学院河南郑州450046 生物芯片北京国家工程研究中心北京102200 北京博奥晶方生物科技有限公司北京102200 河南中医药大学第一附属医院河南郑州450000

目的:利用基因集富集分析(gene set enrichment analysis,GSEA)和巨噬细胞炎症反应模型,基于通路水平阐释补肺健脾方干预慢性阻塞性肺疾病的配伍机制。方法:利用LPS诱导巨噬细胞建立炎症反应模型,分别给予补肺健脾方的12味中药干预,利用... 详细信息

目的:利用基因集富集分析(gene set enrichment analysis,GSEA)和巨噬细胞炎症反应模型,基于通路水平阐释补肺健脾方干预慢性阻塞性肺疾病的配伍机制。方法:利用LPS诱导巨噬细胞建立炎症反应模型,分别给予补肺健脾方的12味中药干预,利用Illumina高通量测序平台得到基因表达谱数据。采用GSEA方法鉴定巨噬细胞炎症反应相关通路,通过富集评分(normalized enrichment score,NES)筛选中药干预后显著回调的通路,揭示补肺健脾方及其配伍的干预机制。结果:与对照组比较,模型组筛选到244条显著扰动通路(GSEA,FDR<0.05)。以得到的显著扰动通路为对象,补肺健脾方所含中药显著回调通路的NES为-1041.56,其中补肺配伍的为-71.25,健脾配伍的为-17.45,温肾配伍的为-211.42,止咳化痰配伍的为-363.94,活血通络配伍的为-377.5;补肺健脾方可显著回调214条通路(逆转率为87.70%),其中补肺配伍的为43条,健脾配伍的为19条,温肾配伍的为133条,止咳化痰配伍的为142条,活血通络配伍的为187条,逆转率分别为17.62%、7.79%、54.51%、58.20%、76.64%。Positive regulation of interleukin 1 production等7条通路在5个配伍中均被显著回调。Mitotic cell cycle arrest等通路在补肺配伍中特异回调。Response to acetylcholine通路在健脾配伍中特异回调。Negative regulation of viral entry into host cell等通路在温肾配伍中特异回调。Negative regulation of leukocyte chemotaxis等通路在止咳化痰配伍中特异回调。Negative regulation of extrinsic apoptotic signaling pathway via death domain receptors等通路在活血通络配伍中特异回调。结论:补肺健脾方各配伍回调炎症反应相关通路的强度及数量均依次为活血通络、止咳化痰、温肾、补肺、健脾配伍。补肺健脾方可通过各配伍回调positive regulation of interleukin 1 production等共性通路及negative regulation of leukocyte chemotaxis等特异性通路干预炎症反应。

关键词：补肺健脾方巨噬细胞炎症反应配伍机制慢性阻塞性肺疾病基因集富集分析

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神经根型颈椎病患者颈椎五步操临床应用研究

西部中医药 2024年第3期37卷 131-136页

作者：徐霞段利冬王亚洁陈志龙程世红成海燕何燕李亚欣甘肃省中医院甘肃兰州730050 甘肃省生态资源监测中心甘肃兰州730020 空军军医大学西京医院陕西西安710032 兰州大学第二临床医学院甘肃兰州730030 甘肃中医药大学甘肃兰州730000

目的:观察颈椎五步操康复锻炼对神经根型颈椎病(cervical spondylotic radiculopathy,CSR)患者的康复效果。方法:将90例CSR保守治疗患者按随机数字表法随机分为试验组和对照组各45例。对照组采取基础护理措施,试验组在对照组基础护理措... 详细信息

目的:观察颈椎五步操康复锻炼对神经根型颈椎病(cervical spondylotic radiculopathy,CSR)患者的康复效果。方法:将90例CSR保守治疗患者按随机数字表法随机分为试验组和对照组各45例。对照组采取基础护理措施,试验组在对照组基础护理措施基础上进行颈椎五步操康复锻炼。比较两组患者入院及出院后各时间点颈椎功能障碍指数量表(neck disability index,NDI)评分、视觉模拟量表(visual analogue scale,VAS)评分、颈椎关节活动度评分变化情况。结果:出院后各时间点两组患者NDI、VAS评分均低于入院时(P<0.01),两组患者颈椎关节活动范围均较入院时改善(P<0.05),试验组改善优于对照组(P<0.01)。结论:颈椎五步操能够有效缓解CSR患者颈痛,改善患者颈椎功能及颈椎关节活动度。

关键词：颈椎病,神经根型颈椎五步操康复护理