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Sandwich Structure-like Meshes Fabricated via Electrospinning for Controllable Release of Zoledronic Acid

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Chemical Research in Chinese Universities 2011年第3期27卷 524-527页

作者： LU Jian LIU Jian-guo SONG Xiao-feng CHEN Xue-si WU, Xiao-dong The First Hospital of Jilin University Changchun 130021 P. R. China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changehun 130022 P. R. China

Novel sandwich structure-like nanofiber multilayered meshes were fabricated via electrospinning. The purpose of the present work was to control zoledronic acid release via the novel structure of sandwich structure-like meshes. The in vitro release experiments reveal that the drug release speed and initial burst release were controllable by adjusting the thicknesses of electrospun barrier mesh and drug-loaded mesh. Compared with those of other drug delivery systems, the main advantages of the sandwich structure-like fiber meshes are facile preparation conditions and the generality for hydrophobic and hydrophilic pharmaceuticals.

关键词： Sandwich structured nanofiber mesh Zoledronic acid Drug release Electrospinning

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髋关节外骨骼机器人实时助力控制研究

自动化技术与应用 2024年第6期43卷 28-31,42页

作者：李晓丽梅珑郭淑英李伟金来安徽三联机器人科技有限公司上海技元机器人科技分公司上海201100 安徽三联机器人科技有限公司安徽合肥230081 安徽三联交通应用技术股份有限公司安徽合肥230081

针对下肢乏力人群对日常训练或者出行的需求,设计可穿戴的髋关节外骨骼,实现对人体意图的精确识别,并在摆动期提供实时的助力。为了实现个体化差异和频繁启停下的助力无延时,提出一种基于下肢动力学模型的重力补偿控制策略,实时计算辅... 详细信息

针对下肢乏力人群对日常训练或者出行的需求,设计可穿戴的髋关节外骨骼,实现对人体意图的精确识别,并在摆动期提供实时的助力。为了实现个体化差异和频繁启停下的助力无延时,提出一种基于下肢动力学模型的重力补偿控制策略,实时计算辅助力矩。通过模型仿真验证算法的可行性;再通过自由行和穿戴外骨骼自由行对比测试,分别验证了髋关节外骨骼对于启停切换瞬间的识别度及适应性、均速步行下的适应性、助力的及时性和有效性。实验结果表明,基于重力补偿的控制策略能够适应周期或者非周期步态下的启停切换,并在摆动期无延时的助力。

关键词：助力外骨骼意图识别重力补偿实时助力机器人模型

Kinetics of leaching lithium from lepidolite using mixture of hydrofluoric and sulfuric acid

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Journal of Central South University 2020年第1期27卷 27-36页

作者： WANG Hai-dong ZHOU An-an guo Hui LÜMeng-hua YU Hai-zhao School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China

The fluorine-based chemical method shows great potential in leaching lithium(Li) from lepidolite. Leaching kinetics of Li in a mixture of sulfuric acid and hydrofluoric acid, which is a typical lixivant for the fluorine-based chemical method, was carried out under crucial factors such as different HF/ore ratios(1:1-3:1 g/mL) and leaching temperatures(50-85℃). The kinetics data fit well with the developed shrinking-core model, indicating that the leaching rate of Li was controlled by the chemical reaction and inner diffusion at the beginning of leaching(0-30 min) as a calculated apparent activation energy(Ea) of 20.62 kJ/mol. The inner diffusion became the rate-limiting step as the leaching continues(60-180 min). Moreover, effects of HF/ore ratio and leaching temperature on selective leaching behavior of Li, Al and Si were discussed. 90% of fluorine mainly existed as HF/F-in leaching solution, which can provide theoretical guidance for further removal or recovery of F.

关键词： lepidolite lithium extraction fluorine-based chemical method hydrofluoric acid selective leaching leaching kinetics

Giant-Capacitance-Induced Wide Quantum Hall Plateaus in Graphene on LaAlO3/SrTiO3 Heterostructures

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Chinese Physics Letters 2020年第7期37卷 86-91页

作者： Ran Tao Lin Li Li-Jun Zhu Yue-dong Yan Lin-Hai guo Xiao-dong Fan Chang-Gan Zeng International Center for Quantum Design of Functional Materials(ICQD) Hefei National Laboratory for Physical Sciences at the Microscaleand Synergetic Innovation Center of Quantum Information and Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics and Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Hybrid structures of two distinct materials provide an excellent opportunity to optimize *** report the realization of wide quantum Hall plateaus in graphene field-effect devices on the LaAlO3/SrTiO3 ***-defined quantized Hall resistance plateaus at filling factors ν=±2 can be obtained over wide ranges of the magnetic field and gate voltage,e.g.,extending from 2 T to a maximum available magnetic field of 9 *** using a simple band diagram model,it is revealed that these wide plateaus arise from the ultralarge capacitance of the ultra-thin LAO layer acting as the dielectric *** is distinctly different from the case of epitaxial graphene on Si C substrates,where the realization of giant Hall plateaus relies on the charge transfer between the graphene layer and interface states in *** results offer an alternative route towards optimizing the quantum Hall performance of graphene,which may find its applications in the further development of quantum resistance metrology.

关键词： quantum realization dielectric

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不同氮效率小麦品种的籽粒灌浆特性

中国土壤与肥料 2024年第3期 174-180页

作者：宋晓张珂珂岳克岳艳军张歆玥黄绍敏郭腾飞郭斗斗张水清李向东丁世杰杨程河南省农业科学院植物营养与资源环境研究所河南郑州450002 河南省农业生态环境重点实验室河南郑州450002 河南心连心化学工业集团股份有限公司河南新乡453000 河南省农业科学院小麦所河南郑州450002

为明确不同氮效率小麦品种的籽粒灌浆特性及其与产量和氮效率的关系,于2019—2021年选取高产氮高效(HH)、高产氮低效(HL)和低产氮低效(LL)小麦品种为试验材料,利用Logistics模型在大田生产条件下模拟籽粒灌浆进程,分析产量构成参数,探... 详细信息

为明确不同氮效率小麦品种的籽粒灌浆特性及其与产量和氮效率的关系,于2019—2021年选取高产氮高效(HH)、高产氮低效(HL)和低产氮低效(LL)小麦品种为试验材料,利用Logistics模型在大田生产条件下模拟籽粒灌浆进程,分析产量构成参数,探究不同氮效率小麦的籽粒灌浆特性差异及其与氮利用效率的关系。结果表明,不同类型品种间的籽粒灌浆特性均存在较大差异。不同品种的最大灌浆速率和平均灌浆速率均表现为HH>HL>LL,达到最大灌浆速率时的籽粒质量则表现为HL>HH>LL,HH与HL之间差异不明显。灌浆活跃期和有效灌浆时间均表现为HH

关键词：小麦高产氮高效氮低效籽粒灌浆

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Microstructure and mechanical properties of as-cast and extruded Mg–8Li–3Al–0.7Si alloy

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Journal of Central South University 2018年第4期25卷 764-771页

作者： YANG guo-qing PENG Xiao-dong YANG Yan LI Meng-luan WEI guo-bing SHAO Hong-yan WANG Bao School of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing 400044China

Mg–8Li–3Al–0.7Si alloy was prepared by casting and deformed by hot extrusion in this *** the microstructure of as-cast and extruded specimens was analyzed with OM,XRD,SEM and *** show that the specimens are composed ofα-Mg,β-Li,AlLi,MgLiAl2 and Mg2Si *** as-extruded specimen,the microstructure is refined and theβ-Li phase has the effect of coordination during *** hot extrusion,Chinese script Mg2Si phase is crushed into block-like and distributes uniformly in the *** properties results show that the strength and elongation are both improved after hot extrusion.

关键词： Mg–Li alloy microstructure mechanical properties extrusion silicon

Effect of prolonging interval time between coronary angiography and percutaneous coronary intervention on X-ray-induced DNA double-strand breaks in blood lymphocytes

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Chinese Medical Journal 2014年第11期127卷 2058-2062页

作者： Zhang guoru Li Yongjun Wang mei guo Bingyan Lyu Xinhu Liu Jin-bo Liu dongchao Chang Liang Department of Cardiovascular Disease Second Hospital of Hebei Medical University Shijiazhuang Hebei 050005 China Department of Cardiology Disease the First Hospital of Shijiazhuang City Shijiazhuang Hebei 050015 China

Background It is desirable to minimize the risk of adverse radiation effects associated with percutaneous coronary *** aim of this study was to determine the impact of prolonging the interval between coronary angiography and percutaneous coronary intervention on X-ray-induced DNA double-strand breaks in blood lymphocytes using γ-H2AX immunofluorescence *** Blood samples of eight patients were taken before the first exposure to ionizing radiation,10 minutes,20 minutes,30 minutes,1 hour,and 24 hours after the last exposure to determine the γ-H2AX foci repair ***-eight patients undergoing percutaneous coronary intervention were randomized to an intermittent radiation exposure group and a continuous radiation exposure *** samples were taken before coronary angiography and 15 minutes after the last *** enumerating γ-H2AX foci,the impact of prolonging the interval on DNA double-strand breaks was *** t-test was used to compare the difference in DNA double-strand breaks between the two *** An increase in foci was found in all patients received percutaneous coronary *** maximum number of γ-H2AX foci was found 10-20 minutes after the end of the last *** was no statistically significant difference between the two groups in γ-H2AX foci at *** average there were （0.79±0.15） γ-H2AX foci induced by interventional X-rays per lymphocyte in the continuous radiation exposure group and （0.66±0.21） in the intermittent radiation exposure group after exposure （P〈0.05）.Conclusions A significant number of γ-H2AX foci develop following the percutaneous coronary intervention *** number of X-ray-induced DNA double-strand breaks may be decreased by prolonging the interval time between coronary angiography and percutaneous coronary intervention to 30 minutes.

关键词： heart catheterization radiation DNA double-strand breaks time factors

Effect of CO2 pneumoperitoneum on the expression of the chemokine receptors CXCR4 and CCR7 in colorectal carcinoma cells in vitro

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Chinese Medical Journal 2013年第24期126卷 4747-4751页

作者： YANG Chun-kang LI guo-dong Y1NG Min-gang XU Ke Department of Abdominal Surgery Fujian Provincial Cancer Hospital Fuzhou Fujian 350014 China Department of Oncology Guizhou Cancer Hospital GuiyangGuizhou 550004 China Provincial Clinical Coliege Fujian Medical University FuzhouFujian 350014 China

Background The ability of pneumoperitoneum in laparoscopic surgery to promote proliferation and metastasis of colorectal cancer has become a focus of research in the field of minimally invasive surgery. The aim of this research was to investigate the effect of CO~ pneumoperitoneum under different pressures and exposed times on the expression of chemokine receptors in colorectal carcinoma cells. Methods We constructed an in vitro pneumoperitoneum model. SW480 colon carcinoma cells were exposed to CO2 pneumoperitoneum under different pressures （6, 9, 12, and 15 mmHg） for 1, 2, and 4 hours. These cells were then cultivated under the same conditions as normal SW480 colon carcinoma cells without CO= pneumoperitoneum （control group）, treated at 37℃, and 5% CO2. The expression of the chemokine receptors CXC receptor 4 （CXCR4） and chemokine C receptor 7 （CCR7） was detected by immunocytochemistry and reverse transcriptase polymerase chain reaction after being cultivated for 0, 24, 48, and 72 hours. Results Immunocytochemistry showed that CXCR4 expression in SW480 cells was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups for the same exposure times compared with controls （P 〈0.05）. CCR7 expression in SW480 cells was significantly decreased in the 12 and 15 mmHg CO2 pneumoperitoneum- treated groups compared with controls （P 〈0.05）. CXCR4 and CCR7 expression increased up to the level of the control group after 24 and 48 hours （P 〉0.05）. If the CO2 pneumoperitoneum pressure increased, CXCR4 and CCR7 expression decreased at all exposure times. If the CO2 pneumoperitoneum exposure time prolonged, there were no significant differences in CXCR4 and CCR7 expression under the same pressure. Under all exposure times, CXCR4 and CCR7 mRNA expression was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups （P 〈0.05） compared with controls, and it increased up to the level of controls after being cultivated for 48

关键词： colorectal neoplasm, C02 pneumoperitoneum chemokine receptor, CXC receptor 4, chemokine C receptor 7

≥35岁居民膳食模式与血脂异常相关性研究:基于赣南慢病队列调查数据

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中国全科医学 2024年第30期27卷 3739-3745页

作者：郑传雷丁睿聪王琪郭逸星李剑黄争春董明华罗晓婷吴清锋赣南医科大学公共卫生与健康管理学院江西省赣州市341000 广东省汕尾市城区疾病预防与控制中心 516600 赣南医科大学基础医学院江西省赣州市341000 赣南医科大学全科医学学院江西省赣州市341000

背景饮食与血脂异常密切相关,传统的营养流行病学关注单一的食物或食物类别,然而日常生活中并不是只消耗单一的营养素或食物。这使得区分个别饮食成分对血脂异常的影响变得更加困难。目前国内外尚无研究探讨赣南地区居民膳食模式与血脂... 详细信息

背景饮食与血脂异常密切相关,传统的营养流行病学关注单一的食物或食物类别,然而日常生活中并不是只消耗单一的营养素或食物。这使得区分个别饮食成分对血脂异常的影响变得更加困难。目前国内外尚无研究探讨赣南地区居民膳食模式与血脂异常之间的关联。目的分析赣南地区≥35岁居民膳食模式和血脂异常患病风险的关联,为制订防治血脂异常营养政策提供科学依据和理论。方法数据来源于赣南慢病队列2020年调查数据,于2020年7—8月,采用多阶段随机抽样的方法从赣南地区≥35岁常住居民中选取调查对象。采用问卷调查和体格检查方法收集居民的基本情况(一般资料、行为习惯、疾病史等),检测空腹血糖和血脂水平,并分析比较不同特征居民血脂异常的患病率。采用食物频率问卷简表进行膳食调查,并运用因子分析法提取膳食模式,将每类膳食模式按照因子得分的四分位数由低到高分为4个亚组Q1、Q2、Q3、Q4。使用Logistic回归分析探讨膳食模式与血脂异常患病风险的相关性。结果本研究共纳入赣南地区≥35岁居民1508名,血脂异常患病率为36.07%(544/1508)。饮水量充足、无高血压史、有糖尿病史的居民血脂异常患病率更高(P<0.05)。通过因子分析共提取出赣南地区4种膳食模式,分别为碳水-蔬菜-水产品类、粗粮-水果-奶类、禽畜肉-腌制品类和蛋类-豆制品类。调整混杂因素后的Logistic回归分析结果显示,相较于Q1水平,赣南地区蛋类-豆制品类膳食模式Q2、Q3水平居民血脂异常的患病风险更低(Q2:OR=0.648,95%CI=0.478~0.879,P=0.005;Q3:OR=0.616,95%CI=0.454~0.836,P=0.002),其他膳食模式尚未表现出对血脂异常患病风险的相关性。结论赣南地区≥35岁居民血脂异常的患病率较高,较高水平蛋类-豆制品类膳食模式可降低居民血脂异常的患病风险;应倡导赣南地区居民合理膳食,可适当增加蛋类和豆制品的摄入。

关键词：血脂异常膳食模式因子分析赣南地区 ≥35岁影响因素分析