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人源性丁酸梭菌的筛选及益生特性研究

河南工业大学学报（自然科学版） 2024年第3期45卷 69-77页

作者：丁长河高军白璐佳孟珺樊俊敏魏书音河南工业大学粮油食品学院河南郑州450001 中原食品实验室河南漯河462000

为了得到人体来源的丁酸梭菌并研究其益生特性,通过选择性培养基筛选、形态学鉴定和分子生物学鉴定相结合的方法,从33位健康志愿者粪便样品中筛选出1株丁酸梭状芽孢杆菌(Clostridium butyricum B-3),以商业化菌株Clostridum butyricum M... 详细信息

为了得到人体来源的丁酸梭菌并研究其益生特性,通过选择性培养基筛选、形态学鉴定和分子生物学鉴定相结合的方法,从33位健康志愿者粪便样品中筛选出1株丁酸梭状芽孢杆菌(Clostridium butyricum B-3),以商业化菌株Clostridum butyricum MIY588作为阳性对照,通过体外模拟试验评价其模拟消化道耐受性、胆盐耐受性、抗生素敏感性、抗氧化能力、体外降血脂能力等。结果表明:Clostridium butyricum B-3对模拟消化道环境及胆盐具有较强的耐受性,模拟胃肠道存活率大于80%;对青霉素、氨苄西林、诺氟沙星、环丙氟哌酸、庆大霉素、阿米卡星具有敏感性,对复方新诺明、红霉素和头孢唑林等具有耐药性;C.butyricum B-3菌悬液(IS)的羟自由基清除率最高,约为80%;两株菌上清液(FS)的DPPH自由基清除率和还原力能力相当,均显著高于IS和无细胞提取物(CFE)(P<0.05);两株菌的IS对两种胆酸盐的结合能力均高于FS;C.butyricum B-3的FS对胰脂肪酶抑制率低于对照菌株,但IS的胰脂肪酶抑制率显著高于对照菌株(P<0.05),为44.02%;C.butyricum B-3的胆固醇清除能力为21.07%,略低于对照菌株。C.butyricum B-3具有作为优良益生菌的潜力,可应用于功能性食品的研发。

关键词：筛选丁酸梭菌益生特性抗氧化降脂

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端面铣削工件表面粗糙度数学模型与实验验证

表面技术 2024年第4期53卷 125-139页

作者：刘德伟许芝令李长河秦爱国刘波张彦彬 Yusuf Suleiman Dambatta 安庆龙青岛理工大学机械与汽车工程学院山东青岛266520 青岛海空压力容器有限公司山东青岛266000 青岛卡沃斯智能制造有限公司山东青岛266109 四川新航钛科技有限公司四川什邡618400 香港理工大学超精密加工技术国家重点实验室中国香港999077 艾哈迈杜·贝洛大学机械工程学院卡杜纳810106尼日利亚上海交通大学机械与动力工程学院上海200240

目的针对多种表面粗糙度影响因素的耦合作用使轮廓形成机理不清,导致表面粗糙度数学模型存在表面质量智能管控工业应用预测精度不足的技术难题,建立端面铣削工件表面粗糙度数学模型。方法首先,基于加工运动学机理和刀具几何学分析端面... 详细信息

目的针对多种表面粗糙度影响因素的耦合作用使轮廓形成机理不清,导致表面粗糙度数学模型存在表面质量智能管控工业应用预测精度不足的技术难题,建立端面铣削工件表面粗糙度数学模型。方法首先,基于加工运动学机理和刀具几何学分析端面铣削工件表面轮廓形成机理,建立考虑刀具跳动的工件表面轮廓模型以及轮廓高度偏差关于铣削力的补偿函数,并通过卷积神经网络(Convolution Neural Network,CNN)进行解析。其次,建立端面铣削表面粗糙度数学模型。最后,进行可转位面铣刀端面铣削ZG32MnMo的实验验证,分别采集轮廓数据与铣削力信号,建立以铣削力为输入、轮廓高度偏差数据为输出的铣削数据集,训练卷积神经网络解析轮廓高度补偿值并验证理论模型的准确性,对比分析考虑刀具跳动的表面粗糙度数学模型与CNN优化考虑刀具跳动的表面粗糙度数学模型的精度。结果CNN优化考虑刀具跳动的表面粗糙度数学模型对加工重叠区与非重叠区内沿刀具进给方向的轮廓算术平均偏差Ra的预测误差分别为18.71%和14.14%,与考虑刀具跳动的表面粗糙度数学模型相比,精度分别提高了10.61%和32.83%,CNN优化考虑刀具跳动的表面粗糙度数学模型对轮廓单元的平均宽度R_(sm)和支承长度率R_(mr(c))的预测结果与实验值吻合。结论考虑刀具跳动以及动态铣削力耦合作用边界条件的表面粗糙度数学模型能够有效预测端面铣削表面粗糙度,可为在质量管控工程中的应用提供理论指导与技术支撑。

关键词：铣削轮廓形成机理表面粗糙度铣削力刀具跳动卷积神经网络

PKP术后骨水泥分布对邻近椎体再发骨折的影响及相关危险因素分析

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实用骨科杂志 2024年第3期30卷 232-237页

作者：廖昌和朱古鑫马航展广州中医药大学广东广州510006 广州市番禺区中医院骨伤科广东广州511400

目的探讨经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)术后骨水泥位置分布对邻近椎体再发骨折的影响及相关危险因素分析。方法收集2021年8月至2023年5月广州市番禺区中医院收治的112例单一节段骨质疏松性椎体压缩骨折(osteoporoti... 详细信息

目的探讨经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)术后骨水泥位置分布对邻近椎体再发骨折的影响及相关危险因素分析。方法收集2021年8月至2023年5月广州市番禺区中医院收治的112例单一节段骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fracture,OVCF)行PKP治疗的患者,根据是否出现再发骨折分为再发骨折组及未骨折组,其中再发骨折组20例,男6例,女14例;年龄60~90岁,平均(77.50±7.34)岁;骨折节段:胸段12例,腰段8例。未骨折组92例,男24例,女68例;年龄51~91岁,平均(72.59±8.29)岁;骨折节段:胸段43例,腰段49例。记录相关临床数据,采用t检验和χ^(2)检验进行单因素分析,Logistics回归模型对再发骨折危险因素进行分析,引用受试者工作特征(receiver operating characteristic,ROC)曲线及曲线下面积(area under curve,AUC)分析危险因素及骨水泥分型对术后再发骨折的预测价值。结果两组患者随访时间为12~17个月,再发骨折组平均随访(13.05±0.89)个月,未骨折组平均随访(12.33±2.20)个月。PKP术后邻近椎体再发骨折的发生率为17.86%,再发骨折患者发病时间为首次PKP术后(27.00±12.33)周。两组患者在年龄、伤椎前缘高度恢复率、术后抗骨质疏松治疗、骨水泥弥散形态、骨水泥渗漏、椎体前缘高度恢复率方面差异均有统计学意义(P<0.05);骨水泥弥散形态、术后未抗骨质疏松治疗、骨水泥渗漏是PKP术后再发骨折的独立影响因素(P<0.05);骨水泥位置分布分型中,骨水泥分布Ⅰ型较Ⅱ~V型术后再发骨折的风险较高(OR=12.764,P<0.05)。骨水泥位置分布分型预测PKP术后出现再发骨折AUC为0.277,灵敏度5.00%,特异度72.80%。结论骨水泥分布I型较其余分型再发骨折风险较高。骨水泥弥散形态、术后未行骨质疏松治疗、骨水泥渗漏均是PKP术后再发骨折的危险因素。

关键词：骨水泥分布再发骨折经皮椎体后凸成形术

Induced Dopaminergic Neurons for Parkinson's Disease Therapy: Targeting the Striatum or Midbrain/Substantia Nigra Pars Compacta?

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Neuroscience Bulletin 2022年第7期38卷 820-824页

作者： Huadong Xu Xu Cheng Qian Song Yuxin Yang changhe Wang Xinjiang Kang Key Laboratory of Medical Electrophysiology Ministry of Education of ChinaThe Institute of Cardiovascular ResearchSouthwest Medical UniversityLuzhou 646000China Neuroscience Research Center Institute of Mitochondrial Biology and MedicineKey Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'an 710049China Department of Neurology The First Affliated Hospital of Xi'an Jiaotong UniversityXian 710061China College of Life Science Liaocheng UniversityLiaocheng 252059China

Parkinson's disease(PD)is a common neurodegenerative disease among the elderly,characterized by the specific loss of dopaminergic(DAergic)neurons in the substantia nigra pars compacta(SNpc)and defects in dopamine(DA)r... 详细信息

关键词： Dopamine Therapy dopamine

甲钴胺联合依帕司他治疗糖尿病周围神经病变的效果及对患者周围神经传导速度的影响

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临床医学工程 2024年第1期31卷 41-42页

作者：万晓娟崔常贺黄河水利委员会黄河中心医院内分泌肾内科河南郑州450003

目的探讨甲钴胺联合依帕司他治疗糖尿病周围神经病变(DPN)的效果。方法将78例DPN患者随机分为两组。对照组应用甲钴胺治疗,观察组则在对照组基础上采用依帕司他治疗。比较两组患者的疗效、神经传导速度与不良反应发生率。结果观察组总... 详细信息

目的探讨甲钴胺联合依帕司他治疗糖尿病周围神经病变(DPN)的效果。方法将78例DPN患者随机分为两组。对照组应用甲钴胺治疗,观察组则在对照组基础上采用依帕司他治疗。比较两组患者的疗效、神经传导速度与不良反应发生率。结果观察组总有效率为97.44%,高于对照组的82.05%(P0.05)。结论甲钴胺联合依帕司他治疗DPN具有较好的效果,可提高神经传导速度,加速患者病症改善,临床价值显著。

关键词：甲钴胺依帕司他糖尿病周围神经病变周围神经传导速度安全性

Tribological Mechanism of Graphene and Ionic Liquid Mixed Fluid on Grinding Interface under Nanofluid Minimum Quantity Lubrication

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 79-96页

作者： Dexiang Wang Yu Zhang Qiliang Zhao Jingliang Jiang Guoliang Liu changhe Li School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdaoChina Key Lab of Industrial Fluid Energy Conservation and Pollution Control(Qingdao University of Technology) Ministry of EducationQingdaoChina

Graphene has superhigh thermal conductivity up to 5000 W/(m·K),extremely thin thickness,superhigh mechanical strength and nano-lamellar structure with low interlayer shear strength,making it possess great potential in mini-mum quantity lubrication(MQL)grinding.Meanwhile,ionic liquids(ILs)have higher thermal conductivity and better thermal stability than vegetable oils,which are frequently used as MQL grinding fluids.And ILs have extremely low vapor pressure,thereby avoiding film boiling in grinding.These excellent properties make ILs also have immense potential in MQL grinding.However,the grinding performance of graphene and ionic liquid mixed fluid under nano-fluid minimum quantity lubrication(NMQL),and its tribological mechanism on abrasive grain/workpiece grinding interface,are still unclear.This research firstly evaluates the grinding performance of graphene and ionic liquid mixed nanofluids(graphene/IL nanofluids)under NMQL experimentally.The evaluation shows that graphene/IL nanofluids can further strengthen both the cooling and lubricating performances compared with MQL grinding using ILs only.The specific grinding energy and grinding force ratio can be reduced by over 40%at grinding depth of 10μm.Work-piece machined surface roughness can be decreased by over 10%,and grinding temperature can be lowered over 50℃at grinding depth of 30μm.Aiming at the unclear tribological mechanism of graphene/IL nanofluids,molecular dynamics simulations for abrasive grain/workpiece grinding interface are performed to explore the formation mechanism of physical adsorption film.The simulations show that the grinding interface is in a boundary lubrication state.IL molecules absorb in groove-like fractures on grain wear flat face to form boundary lubrication film,and graphene nanosheets can enter into the grinding interface to further decrease the contact area between abrasive grain and workpiece.Compared with MQL grinding,the average tangential grinding force of graphene/IL nanofluids can decrease up to 10.8%.The interlayer sh

关键词： Grinding Nanofluid minimum quantity lubrication Graphene Tribological mechanism

Evaluation and Trend Analysis of Surface Water Quality in Zhengzhou in 1998-2008

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Chinese Journal of Population,Resources and Environment 2012年第4期10卷 44-51页

作者： du Xile Lu changhe Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences

Water pollution is one of the major environmental problems,especially in urban areas.due to rapid urban expansion and industrialization,water pollution in Zhengzhou City,the capital of Henan Province in central China has become a serious problem for its development.In this study,the surface water quality was evaluated using Nemerow Comprehensive Pollution Index (NCPI),and the change trend was calculated using methods of Mann-Kendall test and Sen's slope estimator,based on the monitoring data from 1998 to 2008.The results show that the NCPI ranged from 3 to 50 in 70% of the monitoring cases,implying that most rivers were seriously polluted.However,this serious polltuon is expected to be gradually improved,as the concentration of water pollutants and NCPI declined significantly in most rivers.Water pollution in reservoirs was much lower than rivers,and the NCPI in the three monitored reservoirs was lower than 3 in most years,and shows a downward trend.Although the surface water quality was gradually improved,great efforts are still needed to enhance the protection and improvement of surface water environment.

关键词：水环境质量评价地表水环境郑州市 Mann-Kendall检验 NCPI 综合污染指数监测数据水体污染

电感耦合等离子体质谱法测定人促红素注射剂中13种杂质元素

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化学分析计量 2024年第3期33卷 12-16页

作者：唐娜陈统华苏超男王嫦鹤陕西省食品药品检验研究院西安710065

建立了电感耦合等离子体质谱法测定人促红素注射剂中Cd、Hg、Pb、As、Co、V、Ni、Sb、Mo、Cu、Cr、Al、Fe共13种杂质元素含量。以Sc、In、Ge为内标,采用ICP-MS法测定,等离子体射频功率为1549 W,载气流量为1.12 L/min。Al、Fe质量浓度在0... 详细信息

建立了电感耦合等离子体质谱法测定人促红素注射剂中Cd、Hg、Pb、As、Co、V、Ni、Sb、Mo、Cu、Cr、Al、Fe共13种杂质元素含量。以Sc、In、Ge为内标,采用ICP-MS法测定,等离子体射频功率为1549 W,载气流量为1.12 L/min。Al、Fe质量浓度在0~50 ng/mL范围内、其余11种元素质量浓度在0~10 ng/mL范围内线性关系良好,相关系数均不小于0.999,样品加标平均回收率为81.5%~118.0%,测定结果的相对标准偏差为1.10%~2.82%(n=6),各元素检出限为0.0015~1.1488 ng/g。不同厂家的人促红素注射剂中13种杂质元素的含量均符合ICH规定。该方法准确性好,灵敏度高,可同时测定多种元素,适用于人促红素注射剂中杂质元素的质量控制。

关键词：人促红素电感耦合等离子体质谱杂质元素

An efficient algorithm for approximate Voronoi diagram construction on triangulated surfaces

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Computational Visual Media 2023年第3期9卷 443-459页

作者： Wenlong Meng Pengbo Bo Xiaodong Zhang Jixiang Hong Shiqing Xin changhe Tu School of Computer Science and Technology Harbin Institute of TechnologyWeihai 264209China School of Computer Science and Technology Shandong UniversityQingdao 266237China

Voronoi diagrams on triangulated surfaces based on the geodesic metric play a key role in many applications of computer graphics.Previous methods of constructing such Voronoi diagrams generally depended on having an exact geodesic metric.However,exact geodesic computation is time-consuming and has high memory usage,limiting wider application of geodesic Voronoi diagrams(GVDs).In order to overcome this issue,instead of using exact methods,we reformulate a graph method based on Steiner point insertion,as an effective way to obtain geodesic distances.Further,since a bisector comprises hyperbolic and line segments,we utilize Apollonius diagrams to encode complicated structures,enabling Voronoi diagrams to encode a medial-axis surface for a dense set of boundary samples.Based on these strategies,we present an approximation algorithm for efficient Voronoi diagram construction on triangulated surfaces.We also suggest a measure for evaluating similarity of our results to the exact GVD.Although our GVD results are constructed using approximate geodesic distances,we can get GVD results similar to exact results by inserting Steiner points on triangle edges.Experimental results on many 3D models indicate the improved speed and memory requirements compared to previous leading methods.

关键词： geodesic Voronoi diagrams(GVDs) triangular surfaces mesh surfaces approximate geodesics Apollonius diagrams