Modification of Ti6Al4V Substrates with Well-defined Zwitterionic Polysulfobetaine Brushes for Improved Surface Mineralization

Osteoconductive mineral coatings are beneficial for improving the osteointegration of metallic orthopedic/dental implants, but achieving adequate structural integration between the surface minerals and underlying metallic substrates has been a significant challenge. Here, we report covalent grafting of zwitterionic poly(sulfobetaine methacrylate) (pSBMA) brushes on the Ti6Al4V substrates to promote the surface-mineralization of hydroxyapatite with enhanced surface mineral coverage and mineral-substrate interfacial adhesion. We first optimized the atom transfer radical polymerization (ATRP) conditions for synthesizing pSBMA polymers in solution. Well-controlled pSBMA polymers (relative molecular weight up to 26,000, PDI = 1.17) with high conversions were obtained when the ATRP was carried out in trifluoroethanol/ionic liquid system at 60 °C. Applying identical polymerization conditions, surface-initiated atom transfer radical polymerization (SI-ATRP) was carried out to graft zwitterionic pSBMA brushes (PDI \u3c 1.20) from the Ti6Al4V substrates, generating a stable superhydrophilic and low-fouling surface coating that inhibited non-specific protein absorptions without compromising the bulk mechanic property of the Ti6Al4V substrates. The zwitterionic pSBMA surface brushes, capable of attracting both cationic and anionic precursor ions during calcium phosphate apatite mineralization, increased the surface mineral coverage from 32% to 71%, and significantly reinforced the attachment of the apatite crystals on the Ti6Al4V substrate. This facile approach to surface modification of metallic substrates can be exploited to generate multifunctional polymer coatings and improve the performance of metallic implants in skeletal tissue engineering and orthopedic and dental care

Major Merger Galaxy Pairs at z = 0: Dust Properties and Companion Morphology

We present an analysis of dust properties of a sample of close major-merger galaxy pairs selected by K_s magnitude and redshift. The pairs represent the two populations of spiral–spiral (S+S) and mixed morphology spiral–elliptical (S+E). The Code Investigating GALaxy Emission software is used to fit dust models to the Two Micron All Sky Survey, Wide-Field Infrared Survey Explorer, and Herschel flux density measurements, and to derive the parameters describing the polycyclic aromatic hydrocarbons contribution, interstellar radiation field, and photodissociation regions. Model fits verify our previous Spitzer Space Telescope analysis that S+S and S+E pairs do not have the same level of enhancement of star formation and differ in dust composition. The spirals of mixed-morphology galaxy pairs do not exhibit the enhancements in interstellar radiation field and therefore dust temperature for spirals in S+S pairs in contrast to what would be expected according to standard models of gas redistribution due to encounter torques. This suggests the importance of the companion environment/morphology in determining the dust properties of a spiral galaxy in a close major-merger pair

Major Merger Galaxy Pairs at z = 0: Dust Properties and Companion Morphology

We present an analysis of dust properties of a sample of close major-merger galaxy pairs selected by K_s magnitude and redshift. The pairs represent the two populations of spiral–spiral (S+S) and mixed morphology spiral–elliptical (S+E). The Code Investigating GALaxy Emission software is used to fit dust models to the Two Micron All Sky Survey, Wide-Field Infrared Survey Explorer, and Herschel flux density measurements, and to derive the parameters describing the polycyclic aromatic hydrocarbons contribution, interstellar radiation field, and photodissociation regions. Model fits verify our previous Spitzer Space Telescope analysis that S+S and S+E pairs do not have the same level of enhancement of star formation and differ in dust composition. The spirals of mixed-morphology galaxy pairs do not exhibit the enhancements in interstellar radiation field and therefore dust temperature for spirals in S+S pairs in contrast to what would be expected according to standard models of gas redistribution due to encounter torques. This suggests the importance of the companion environment/morphology in determining the dust properties of a spiral galaxy in a close major-merger pair

Synthesis of New Pharmacophore Scaffolds

The photo-initiated cyclization of aryl-vinyl ethers has been shown to create multicyclic natural product-like scaffolds with predicted biological activity. Utilizing this method, one can construct up to three fused rings and six chiral centers in a single experimental operation. A chemo-informatics analysis of these structures has identified scaffolds which are likely to interact with proteins. Using these predictions, our group has constructed two scaffolds with predicted biological activity

Alzheimer's Disease Screening

Develop a plan for the screening of the general public for Alzheimer’s Disease

SUSTAINABLE PAPER INSULATION FOR KAMBASHUS IN INFORMAL SETTLEMENTS OF NAMIBIA

The metal shacks of Katutura are unbearably hot in the summer and cold in winter. The goal of this project was to develop sustainable paper insulation to improve thermal regulation in shacks. We conducted testing on fire safety, effective insulating materials, and production techniques. To develop a background of social and technical understanding, we researched low-cost insulation projects and interviewed several members of the community. In collaboration with Katutura residents and members of the Men on the Side of the Road Project, we developed an effective prototype of the paper insulation sheet. We provided recommendations for the Men on the Side of the Road Project to support continued research, large-scale testing, and further development of paper insulation