Hydrogels have been investigated extensively as biomaterials for three-dimensional tissue reconstruction and regeneration. Incorporation of... Show moreHydrogels have been investigated extensively as biomaterials for three-dimensional tissue reconstruction and regeneration. Incorporation of tissue-specific features into synthetic materials is difficult, due to limited ability to recreate the complex multi-component nature of extracellular matrices (ECM). ECM-rich hydrogels extracted and assembled from soft tissues have been shown to stimulate the formation of vascularized tissue in vitro and in vivo.1,2,3 Hydrogels derived from dermal tissue using this technique contain basement membrane proteins, including laminin 3, collagen IV, and collagen VII, all of which are essential for proper skin function.2 While these materials have significant biological activity, their poor mechanical properties and rapid degradation in vivo hinder their performance in wound healing applications. This study investigates the effect of covalent crosslinking on the mechanical properties, biological activity, and degradation (in vitro and in vivo) of dermal-derived hydrogels. Glutaraldehyde (GA) is a well-known crosslinking agent used in clinically approved products to prolong lifetime and increase strength of materials. Compression tests indicated increasing elastic modulus and yield stress of crosslinked hydrogels with crosslinking time (p<0.05). The crosslinked ECM were resistant to pepsin degradation in vitro. Gels and gel extracts were non toxic, and fibroblasts adhered and spread on gels at all crosslink densities. Crosslinking drastically slowed degradation relative to controls (non-crosslinked gels) in vivo in a subcutaneous implant model relative to control. While degradation was slowed, inflammation was low and mature vascularized tissue formed in the gels, suggesting that the materials retained the ability to induce tissue invasion. These results support the potential use of dermis-derived hydrogels as promising constructs for applications in tissue engineering and suggest that covalent crosslinking can be used to enhance mechanical properties and prolong hydrogel lifetime while inducing vascularized tissue formation. Based on this research, IIT biomedical engineering undergraduate senior Sophia Pilipchuk was named one of five recipients of the Biomedical Engineering Society (BMES) Undergraduate Student Award, to be presented in October 2011 at the BMES Annual Business Meeting in Hartford, Connecticut. Up to eight undergraduate students are selected from around the country on the basis of originality, significance, thoroughness of design analysis, and performance evaluation. Show less
Logan Arcade is a new arcade-bar that opened just February 2014. It features over twenty-five pinball machines and forty-five vintage arcade... Show moreLogan Arcade is a new arcade-bar that opened just February 2014. It features over twenty-five pinball machines and forty-five vintage arcade-games. Owner Jim Zespy collects and restores arcade games, including those in the arcade. His collection started in 2009; he seeks out games from the mid-1970s through the present. He often buys broken arcade machines and fixes them. Any machine that couldn't be fixed is as spare parts to maintenance other arcade machines. Zespy chooses games to be placed in the arcade based on the games’ popularity with the general public. He first balanced all different eras, and placed different kinds of games to try to have a balance. Afterward he watched to see which games people gravitated to, then took out the games people didn't like and placed more popular games. Zespy’s daily concern is the maintenance of the arcade machines. Logan Arcade has its own Local Pinball League, for which the game changes every week. While the league has scoring, and there is some competition, it's meant to encourage participants to play different games, get to know them, and get to know other people. Some players have made major records in the Logan Arcade. These records are on games including Nibbler, Tron Ice Score, and Tetris. Show less
The document is a compilation of the Baseline Assessment, Foreman Survey, and Exit Interview documents for National Science Foundation... Show moreThe document is a compilation of the Baseline Assessment, Foreman Survey, and Exit Interview documents for National Science Foundation research project, CMMI-1100514, Flexible Decision-making in Response to Disruptive Events on Construction Sites. Sponsorship: National Science Foundation, CMMI-1100514, Flexible Decision-making in Response to Disruptive Events on Construction Sites. Show less
A tutorial to help you learn the Mathematica tools that are particularly useful in engineering. Note that some of the graphics output has been... Show moreA tutorial to help you learn the Mathematica tools that are particularly useful in engineering. Note that some of the graphics output has been removed from the download version to reduce the size of the notebook. Evaluate the notebook to regenerate these and complete the notebook. Show less