Nanocellulose from the Appalachian Hardwood Forest and Its Potential Applications

Nanofibrillated cellulose (NFCs) are nanoscale fibers of high aspect ratio that can be isolated from a wide variety of cellulosic sources, including wood and bacterial cellulose. With high strength despite of their low density, NFCs are a promising renewable building block for the preparation of nanostructured materials and composites. To fabricate NFC-based materials with improved mechanical and chemical properties and additional new functionalities for different applications, it is essential to tailor the surface properties of individual NFCs. The surface structures control the interactions between NFCs and ultimately dictate the structure and macroscale properties of the bulk material. This research was focused on determining the feasibility of using hardwood residues from the Appalachian Hardwood Forest for the production of nanofibrillated cellulose (NFC). In addition, some modifications during the NFC production process were performed to evaluate their improvement to incorporate more antimicrobial copper in the cellulosic backbone. This thesis has been divided in the following main chapters: 1) Literature review regarding to nanocellulosic materials and their production processes, 2) Nanocellulose current and potential applications, 3) Nanofibrillated cellulose from the Appalachian Hardwood logging residues, 4) Modified nanofibrillated from the Appalachian Hardwood logging residues, 5) Preparation of nanocellulose using ionic liquids -- A review, 6) Nanocellulose-based drug delivery system -- A review, 7) Safety aspects on the utilization of lignocellulosic based materials - A review

Effects of Dip-coated films on the Properties of Implantable Intracortical Microelectrodes

The successful clinical use of implantable intracortical microelectrodes (ICMs) to treat certain types of deafness, blindness, and paralysis is limited by a reactive tissue response (RTR) of the brain. This RTR culminates in the formation of a tight glial scar and a loss of neuronal density around implanted ICMs, and is accompanied by a decrease in signal to noise ratio and an increase in impedance. While no comprehensive mechanistic understanding of the underlying biology is currently agreed upon in the field, a general consensus exists around a highly volatile acute RTR phase. During this acute phase, the electrical properties of ICMs do not always coincide with cellular responses, and the extent of initial injury appears to greatly influence the degree of the chronic RTR. While many electrode modifications and treatments are effective in the short term, the chronic RTR appears impervious to most interventions. To better understand the acute phase of the RTR, this dissertation aims to investigate the effects of various dip-coated biomolecules on the electrical properties of ICMs and cellular responses to microscale ICM-like foreign bodies. We first present an examination of silica sol-gel thin films as a potential biomolecule delivery platform which does not adversely affect the electrical properties of ICMs. The second study shows that adsorbed proteins, thought to play an important role in modulating the RTR, cause significant increases in electrode impedance. In contrast to prevalent electrical models of the electrode tissue interface which assume purely resistive impedance changes due to adsorbed proteins, our results show both resistive and capacitive changes. We also show that increases in impedance related to protein adsorption can be prevented by dip coating ICMs in an aqueous solution of high molecular weight polyethylene glycol (PEG). We then describe a method to clean electrode sites using direct current (DC) biasing, showing that DC biasing is capable of restoring electrode impedance following exposure to enzymatic cleaning solutions, proteins, phantom brains, and actual brain tissue. The final study in an in vitro mixed primary cortical cell culture model shows that lipopolysaccharide (LPS), a well-known ligand to toll-like 4 (TL4) receptors, dip-coated onto segments of metal microwire, can simulate localized inflammation around an implanted ICM. We observe elevated activation of glial cells in interface regions, and extending into more distant regions. This elevation in glial responses is not accompanied by a decrease in neuronal density. We additionally show that microwire dip-coated with a mixture of LPS and PEG exhibits significantly lower microglial and astrocyte responses. These findings highlight the importance of adsorbed proteins, some of which are implicated in aggravating the reactive tissue response, but which we show can result in significant increases in electrode impedance before the RTR even begins. These impedance changes can be prevented through the use of dip-coated PEG. Our cell culture data presents further evidence for the attractiveness of TL4 receptors as a target for intervention, and suggests that the loss of neuronal density observed in vivo is better explained by other mechanisms following device insertion than pure glial activation

STEM Undergraduate Research Symposium 2017 Full Program

Full program of the 2017 LSSF STEM Undergraduate Research Conference

Biomedical Engineering

Biomedical engineering is currently relatively wide scientific area which has been constantly bringing innovations with an objective to support and improve all areas of medicine such as therapy, diagnostics and rehabilitation. It holds a strong position also in natural and biological sciences. In the terms of application, biomedical engineering is present at almost all technical universities where some of them are targeted for the research and development in this area. The presented book brings chosen outputs and results of research and development tasks, often supported by important world or European framework programs or grant agencies. The knowledge and findings from the area of biomaterials, bioelectronics, bioinformatics, biomedical devices and tools or computer support in the processes of diagnostics and therapy are defined in a way that they bring both basic information to a reader and also specific outputs with a possible further use in research and development

Technology 2001: The Second National Technology Transfer Conference and Exposition, volume 2

Proceedings of the workshop are presented. The mission of the conference was to transfer advanced technologies developed by the Federal government, its contractors, and other high-tech organizations to U.S. industries for their use in developing new or improved products and processes. Volume two presents papers on the following topics: materials science, robotics, test and measurement, advanced manufacturing, artificial intelligence, biotechnology, electronics, and software engineering

Energy Materials Coordinating Committee (EMaCC): Fiscal year 1996. Annual technical report

The DOE Energy Materials Coordinating Committee (EMaCC) serves primarily to enhance coordination among the Department`s materials programs and to further effective use of materials expertise within the Department. These functions are accomplished through the exchange of budgetary and planning information among program managers and through technical meetings/workshops on selected topics involving both DOE and major contractors. In addition, EMaCC assists in obtaining materials-related inputs for both intra- and interagency compilations. The EMaCC reports to the Director of the Office of Energy Research in his or her capacity as overseer of the technical programs of the Department. This annual technical report is mandated by the EMaCC terms of reference. This report summarizes EMaCC activities for FY 1996 and describes the materials research programs of various offices and divisions within the Department

Bibliography of Lewis Research Center Technical Publications announced in 1991

This compilation of abstracts describes and indexes the technical reporting that resulted from the scientific engineering work performed and managed by the Lewis Research Center in 1991. All the publications were announced in the 1991 issues of STAR (Scientific and Technical Aerospace Reports) and/or IAA (International Aerospace Abstracts). Included are research reports, journal articles, conference presentations, patents and patent applications, and theses

ReSCon '12, Research Student Conference: Book of Abstracts

The fifth SED Research Student Conference (ReSCon2012) was hosted over three days, 18-20 June 2012, in the Hamilton Centre at Brunel University. The conference consisted of 130 oral and 70 poster presentations, based on the high quality and diverse research being conducted within the School of Engineering and Design by postgraduate research students. The conference is held annually, and ReSCon plays a key role in contributing to research and innovations within the School