Nitric oxide (NO) plays an important role in physiological functions in the body, naturally synthesized by nitric oxide synthase. NO was discovered as the endotheliumderived relaxing factor, allowing for vasodilation to occur in blood vessels, thus preventing platelet aggregation. It is also known as an antimicrobial agent. As it has been shown to enhance wound healing, recent efforts have been made to incorporate NO into thromboresistant polymers for medical devices. In this work, an acrylonitrile-co-1-vinylimidazole (AN/ VIM) copolymer was melt-spun to produce a surgical suture type material with high durability and tensile strength which can store and release NO. The acrylonitrile (AN) comonomers are stabilized in the melt-spinning process, allowing for the formation of the NO molecular donor group, a diazeniumdiolate or NONOate. When AN/VIM is reacted with NO, the NONOate will form on AN segments. Each NONOate releases two molar equivalents of NO upon reaction with a proton source. The fiber mechanical properties were maintained after the polymer is reacted with NO. To control the release of NO, the suture is dipped in polycaprolactone (PCL), creating a porous coating on the fiber. A delayed release is desired in order for NO to be effective in wound healing over long periods of time. The biodegradable coating significantly slows release of the NO compared to the uncoated fiber. Over a course of 3 days, the PCL coated melt-spun AN/VIM copolymer releases a total of 84 μmol NO/g.

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Carbon fiber polymer composites have attracted worldwide interest in sporting goods and aerospace industries due to their excellent specific strength, stiffness and lightweight. The replacement of solution-spinning process by melt-spinning process is one of the major approaches to make cost effective carbon fiber. In recent years, researchers have explored the possibilities to synthesize melt processable carbon fiber precursors, but their thermal stabilization is still a challenge. The goal for this research project is to prepare melt processable carbon fiber precursors which have the capability of thermal stabilization. Acrylonitrile/1-vinylimidazole (AN/VIM) copolymers containing various mol% of VIM were synthesized by free radical solution polymerization. The copolymers were characterized by Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, 1 H-NMR spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). 82/18 mol percent of AN/VIM copolymer based carbon fiber precursor was processed by melt spinning at 192 °C and thermal stabilization of the melt-spun fiber was achieved by heating in air at 250 °C for 5 hrs. The change of fiber structure during stabilization process was confirmed with ATR-IR spectra. Tan Delta value of the stabilized fiber is 0.17, which is much lower than that of as-spun fiber, about 2.12. The oxidized fiber (250 °C / 5 h) did keep its shape after carbonization at 1000 °C for 2 h, which indicates that poly (acrylonitrile-co-1-vinylimidazole) melt-spun fiber after thermal stabilization can be carbonized. A novel dispersion polymerization of poly (acrylonitrileco-1iii vinylimidazole) by using small amount of protonated copolymer itself as a stabilizer was also introduced in this study. Poly (acrylonitrileco-1-vinylimidazolium tetrafluoroborate) and poly (acrylonitrileco-1-vinylimidazolium hexafluorophosphate) were synthesized for gas separation membranes. Terpolymers of methyl methacrylate, methyl acrylate and furfuryl methacrylate (MMA/MA/FMA) were synthesized successfully by solution polymerization and emulsion polymerization and were characterized by 1 H NMR, ATR-IR and DSC. The thermo-reversible property of MMA/MA/FMA and BMI cross-linked polymer was confirmed by solubility test. The MMA/MA/FMA and BMI cross-linked polymer emulsion can be applied for making thermally re-moldable carbon fiber composite. iv DEDICATION I dedicate this work to my parents. I am blessed for being their daughter. v ACKNOWLEDGMENTS I want to deeply thank Prof. Dennis W. Smith, Jr. for his tremendous support throughout my graduate study. I would like to express gratitude to Prof. Rhett C. Smith for his guidance and help. I would like to thank my committee members, Prof. Stephen. E. Creager, Prof.

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In this paper, we present the Intra- and Inter-Human Relation Networks I²R-Net for Multi-Person Pose Estimation. It involves two basic modules. First, the Intra-Human Relation Module operates on a single person and aims to capture Intra-Human dependencies. Second, the Inter-Human Relation Module considers the relation between multiple instances and focuses on capturing Inter-Human interactions. The Inter-Human Relation Module can be designed very lightweight by reducing the resolution of feature map, yet learn useful relation information to significantly boost the performance of the Intra-Human Relation Module. Even without bells and whistles, our method can compete or outperform current competition winners. We conduct extensive experiments on COCO, CrowdPose, and OCHuman datasets. The results demonstrate that the proposed model surpasses all the state-of-the-art methods. Concretely, the proposed method achieves 77.4% AP on CrowPose dataset and 67.8% AP on OCHuman dataset respectively, outperforming existing methods by a large margin. Additionally, the ablation study and visualization analysis also prove the effectiveness of our model.