111 research outputs found

    Synthesis of well-defined polymer brushes grafted onto silica nanoparticles via surface reversible addition-fragmentation chain transfer polymerization

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    ABSTRACT: Reversible addition-fragmentation chain transfer polymerization (RAFT) was used to prepare polymer brushes grafted onto silica nanoparticles. Novel RAFT-silane agents were prepared that contained both an active RAFT moiety and a silane coupling agent. RAFT agents were anchored to silica nanoparticles by the functionalization of colloidal silica with the RAFT-silane agents. RAFT polymerizations were then conducted from the particle surface to graft homopolymer and block copolymer brushes to the particles. The kinetics of styrene (St) and n-butyl acrylate (nBuA) surface RAFT polymerizations were investigated and compared with model polymerizations mediated by free RAFT agent. The molecular weights of grafted polymers increased linearly with conversions, and first-order kinetics were observed in the conversion range studied, indicating that the surface graft polymerization proceeded in a controlled manner. Well-defined PSt-block-PBuA copolymers attached to silica nanoparticles were also prepared

    A Kinematic Model of the Shoulder Complex Obtained from a Wearable Detection System

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    Due to the complex coupled motion of the shoulder mechanism, the design of the guiding movement rules of rehabilitation robots generally lacks specific motion coupling information between the glenohumeral (GH) joint center and humeral elevation angle. This study focuses on establishing a kinematic model of the shoulder complex obtained from a wearable detection system, which can describe the specific motion coupling relationship between the GH joint center displacement variable quantity relative to the thorax coordinate system and the humeral elevation angle. A kinematic model, which is a generalized GH joint with a floating center, was proposed to describe the coupling motion. Twelve healthy subjects wearing the designed detection system performed a right-arm elevation in the sagittal and coronal planes respectively, and the motion information of the GH joint during humeral elevation in the sagittal and coronal planes was detected and quantized, with the analytical formulas acquired based on the experimental data. The differences in GH joint motion during humeral elevation in the sagittal and coronal planes were also evaluated respectively, which also verified the effectiveness of the proposed kinematic model.</jats:p

    A Modified Kinematic Model of Shoulder Complex Based on Vicon Motion Capturing System: Generalized GH Joint with Floating Centre

    No full text
    Due to the complex coupling motion of shoulder mechanism, only a small amount of quantitative information is available in the existing literature, although various kinematic models of the shoulder complex have been proposed. This study focused on the specific motion coupling relationship between glenohumeral (GH) joint center displacement variable quantity relative to the thorax coordinate system and humeral elevation angle to describe the shoulder complex. The mechanism model of shoulder complex was proposed with an algorithm designed. Subsequently, twelve healthy subjects performed right arm raising, lowering, as well as raising and lowering (RAL) movements in sixteen elevation planes, and the motion information of the markers attached to the thorax, scapula, and humerus was captured by using Vicon motion capturing system. Then, experimental data was processed and the generalized GH joint with floating center was quantized. Simultaneously, different coupling characteristics were detected during humerus raising as well as lowering movements. The motion coupling relationships in different phases were acquired, and a modified kinematic model was established, with the description of overall motion characteristics of shoulder complex validated by comparing the results with a prior kinematic model from literature, showing enough accuracy for the design of upper limb rehabilitation robots.</jats:p

    Immunotherapy with heat shock protein 96 to treat gliomas

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    AbstractHeat shock protein 96 (gp96) is a highly conserved protein in the endoplasmic reticulum. The functions of gp96 include promoting the oncogenesis and progression of glioma. In addition, tumor-derived gp96 can activate anti-tumor immune. Therefore, this protein was used to generate an anti-tumor vaccine and widely applied to glioma therapy. This review summarizes the mechanisms of gp96 in glioma oncogenesis and clinical trials of the gp96 tumor vaccine in glioma treatment.</jats:p

    effectoftemperatureongrowthandartemisininbiosynthesisinhairyrootculturesofartemisiaannua

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    本实验研究了不同温度(15℃~35℃)对青蒿毛状根生长和青蒿素生物合成的影响,发现25℃有利于毛状根生长,30℃促进了青蒿素生物合成。通过温度改变的二步培养技术(培养前20d温度控制在25℃,后10d温度提高到30℃),青蒿素的产量得到明显提高,高于在恒温培养时(25℃或30℃)的结果

    A Modified Kinematic Model of Shoulder Complex Based on Vicon Motion Capturing System: Generalized GH Joint with Floating Centre

    No full text
    Due to the complex coupling motion of shoulder mechanism, only a small amount of quantitative information is available in the existing literature, although various kinematic models of the shoulder complex have been proposed. This study focused on the specific motion coupling relationship between glenohumeral (GH) joint center displacement variable quantity relative to the thorax coordinate system and humeral elevation angle to describe the shoulder complex. The mechanism model of shoulder complex was proposed with an algorithm designed. Subsequently, twelve healthy subjects performed right arm raising, lowering, as well as raising and lowering (RAL) movements in sixteen elevation planes, and the motion information of the markers attached to the thorax, scapula, and humerus was captured by using Vicon motion capturing system. Then, experimental data was processed and the generalized GH joint with floating center was quantized. Simultaneously, different coupling characteristics were detected during humerus raising as well as lowering movements. The motion coupling relationships in different phases were acquired, and a modified kinematic model was established, with the description of overall motion characteristics of shoulder complex validated by comparing the results with a prior kinematic model from literature, showing enough accuracy for the design of upper limb rehabilitation robots
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