Biologically Enhanced Cathode Design For Improved Capacity And Cycle Life For Lithium-Oxygen Batteries,
2013
Massachusetts Institute of Technology
Biologically Enhanced Cathode Design For Improved Capacity And Cycle Life For Lithium-Oxygen Batteries, Dahyun Oh, Jifa Qi, Yi-Chun Lu, Yong Zhang, Yang Shao-Horn, Angela Belcher
Faculty Publications
Lithium-oxygen batteries have a great potential to enhance the gravimetric energy density of fully packaged batteries by two to three times that of lithium ion cells. Recent studies have focused on finding stable electrolytes to address poor cycling capability and improve practical limitations of current lithium-oxygen batteries. In this study, the catalyst electrode, where discharge products are deposited and decomposed, was investigated as it has a critical role in the operation of rechargeable lithium-oxygen batteries. Here we report the electrode design principle to improve specific capacity and cycling performance of lithium-oxygen batteries by utilizing high-efficiency nanocatalysts assembled by M13 virus …
Advances In Homology Directed Genetic Engineering Of Human Pluripotent And Adult Stem Cells,
2013
Santa Clara University
Advances In Homology Directed Genetic Engineering Of Human Pluripotent And Adult Stem Cells, Kalpith Ramamoorthi, Donald Curtis, Prashanth Asuri
Bioengineering
The ability to introduce precise genomic modifications in human cells has profound implications for both basic and applied research in stem cells, ranging from identification of genes regulating stem cell self-renewal and multilineage differentiation to therapeutic gene correction and creation of in vitro models of human diseases. However, the overall efficiency of this process is challenged by several factors including inefficient gene delivery into stem cells and low rates of homology directed site-specific targeting. Recent studies report the development of novel techniques to improve gene targeting efficiencies in human stem cells; these methods include molecular engineering of viral vectors o …
Engineered Nanotopography On Electrospun Plla Microfibers Modifies Raw 264.7 Cell Response,
2013
Missouri University of Science and Technology
Engineered Nanotopography On Electrospun Plla Microfibers Modifies Raw 264.7 Cell Response, Nicholas J. Schaub, Tara Britton, Rupak Rajachar, Ryan J. Gilbert
Chemical and Biochemical Engineering Faculty Research & Creative Works
In this study, we created a new method of electrospinning capable of controlling the surface structure of individual fibers (fiber nano topography). The nano topographical features were created by a phase separation in the fibers as they formed. To control the phase separation, a nonsolvent (a chemical insoluble with the polymer) was added to an electrospinning solution containing poly-l-lactic acid (PLLA) and chloroform. The nano topography of electro spun fibers in the PLLA/chloroform solution was smooth. However, adding a small weight (< 2% of total solution) of a single nonsolvent (water, ethanol, or dimethyl sulfoxide) generated nanoscale depressions on the surface of the fibers unique to the nonsolvent added. Additionally, nanoscale depressions on electro spun fibers were observed to change with dimethyl sulfoxide (DMSO) concentration in the PLLA/chloroform solution. A nonlinear relationship was found between the concentration of DMSO and the number and size of nano topographical features. The surface depressions did not alter the hydrophobicity of the scaffold or degradation of the scaffold over a two-day period. To determine if fiber nano topography altered cell behavior, macrophages (RAW 264.7 cells) were cultured on fibers with a smooth nano topography or fibers with nanoscale depressions. RAW 264.7 cells spread less on fibers with nanoscale depressions than fibers with a smooth topography (p < 0.05), but there were no differences between groups with regard to cell metabolism or the number of adherent cells. The results of this study demonstrate the necessity to consider the nano topography of individual fibers as these features may affect cellular behavior. More importantly, we demonstrate a versatile method of controlling electro spun fiber nano topography. © 2013 American Chemical Society.
Mammalian Cells Preferentially Internalize Hydrogel Nanodiscs Over Nanorods And Use Shape-Specific Uptake Mechanisms,
2013
University of Texas at Austin
Mammalian Cells Preferentially Internalize Hydrogel Nanodiscs Over Nanorods And Use Shape-Specific Uptake Mechanisms, Rachit Agarwal, Vikramjit Singh, Patrick Jurney, Li Shi, S. Sreenivasan, Krishnendu Roy
Faculty Publications
Size, surface charge, and material compositions are known to influence cell uptake of nanoparticles. However, the effect of particle geometry, i.e., the interplay between nanoscale shape and size, is less understood. Here we show that when shape is decoupled from volume, charge, and material composition, under typical in vitro conditions, mammalian epithelial and immune cells preferentially internalize disc-shaped, negatively charged hydrophilic nanoparticles of high aspect ratios compared with nanorods and lower aspect-ratio nanodiscs. Endothelial cells also prefer nanodiscs, however those of intermediate aspect ratio. Interestingly, unlike nanospheres, larger-sized hydrogel nanodiscs and nanorods are internalized more efficiently than their smallest counterparts. …
Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials,
2013
Purdue University
Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi
The Summer Undergraduate Research Fellowship (SURF) Symposium
Motor proteins such as kinesin move along microtubules in order to transport cellular cargos throughout the cell by obtaining energy from RNA hydrolysis which allows the cell to complete the tasks needed to stay alive. In this work, we developed synthetic molecular motors using DNA enzymes (DNAzyme) and fluorescent nanomaterials which mimic the functions and structures of motor proteins. A DNAzyme-capped CdS nanoparticle and a RNA-functionalized single-walled carbon nanotube (SWCNT) were used as a walker and a track in the motor platform, respectively. As a walking mechanism, the DNAzyme cleaved the RNA substrates in the presence of metal cations. The …
Bicistronic Design For Precise And Reliable Gene Expression,
2013
Purdue University
Bicistronic Design For Precise And Reliable Gene Expression, Nidhi N. Menon, Jenna Rickus
The Summer Undergraduate Research Fellowship (SURF) Symposium
Despite having progressed extensively in the field of synthetic biology in terms of DNA synthesis, analysis and transplanting, we still cannot reliably, quantitatively measure expression of new genetic constructs. We engineered a biobrick compatible expression cassette to control transcription and translation initiation which can be reused in new genetic contexts. Previous research has shown that the Bicistronic design have much lesser variations in expression with varying genes of interest as compared to the regular monocistronic design.(Mutalik, Endy, Guimaraes, Cambray, Lam, Juul, Tran & Paull, 2013) The Bicistronic design(BCD) consists of two Shine-Dalgarno sequences in its translation element which when combined …
In Vivo Flow Measurements Of Murine Renal Arteries And Veins With High Frequency Ultrasound,
2013
Purdue University
In Vivo Flow Measurements Of Murine Renal Arteries And Veins With High Frequency Ultrasound, Amy E. Bogucki, Hilary D. Schroeder, Alexa A. Yrineo, Craig J. Goergen
The Summer Undergraduate Research Fellowship (SURF) Symposium
The number of glomeruli in the kidneys has been shown to have an effect on the decline in renal function over time (Brenner, Garcia, Anderson 1988). Furthermore, flow in the renal arteries and veins may depend on the number of glomeruli in the kidney. Consistent in vivo measurements of volumetric flow in the renal arteries and veins are difficult to obtain. Thus, the purpose of this study was to develop non-invasive imaging techniques capable of estimating arterial and venous flow to kidneys. A high-frequency small animal ultrasound system was chosen based upon its excellent spatial and temporal resolution when imaging …
Determination Of Master Compliance Curve For Extruded Semolina Pasta,
2013
Purdue University
Determination Of Master Compliance Curve For Extruded Semolina Pasta, Laura E. Emery, Martin Okos
The Summer Undergraduate Research Fellowship (SURF) Symposium
The dependence of the rate of relaxation of semolina pasta on moisture content and temperature and how it affects shrinkage during drying has not yet been determined. The purpose of this research was to develop an equation that relates moisture content and temperature in order to obtain a master curve for creep of the product. When found, this equation could help to optimize the drying process and increase the quality of the final pasta product. Semolina flour mixed with water and propionic acid to create a 35% wet basis product was extruded on a C.W. Brabender 2523 to obtain a …
Artificial Yeast Polarization Controlled By Chemical Gradient,
2013
Purdue University
Artificial Yeast Polarization Controlled By Chemical Gradient, James K. Nolan, Bernard Tao
The Summer Undergraduate Research Fellowship (SURF) Symposium
Engineering synthetic multicellular systems will lead to new synthetic biology technological platforms, inform developmental biology through recapitulation of natural systems and possibly unveil novel morphologies with practical applications not before reached throughout natural history (Maharbiz, 2012). Creating an exogenous molecular circuit that will polarize unicellular cells into “apical” and “basal” domains relative to a substrate plane would fulfill a missing component towards fully multicellular synthetic cellular communities (Maharbiz, 2012). To this end, a PIP3 polarization network previously designed by Chau and associates (Chau, Walter, Gerardin, Tang, Lim 2012) was coupled to the specific activation by niacin of a recombinant …
The Efficacy And Optimization Of Somatosensory Intracortical Microstimulation In Rats,
2013
Purdue University
The Efficacy And Optimization Of Somatosensory Intracortical Microstimulation In Rats, Sean P. Mcdowell, Ryan S. Verner, Kevin J. Otto Dr.
The Summer Undergraduate Research Fellowship (SURF) Symposium
Demand exists for brain-machine interfaces that offer a wide range of sensory feedback along with volitional motor control to individuals with limited control of natural sensory or motor function. As these sensorimotor devices are developed, it is necessary to improve the interaction between the prostheses and higher-level cortical structures. Optimizing these somatosensory stimulation parameters will require the use of a high-throughput experimental design. To address this, one Sprague-Dawley rat was trained to respond to auditory stimuli during a conditioned-avoidance behavior task and then implanted with a penetrating microelectrode array in the part of the somatosensory cortex corresponding to the left …
In Vivo Method For Labeling And Tracking Cells In The Mammalian Limb Bud,
2013
Purdue University
In Vivo Method For Labeling And Tracking Cells In The Mammalian Limb Bud, James T. Mccarthy, Andrew Schilb, Sarah Calve
The Summer Undergraduate Research Fellowship (SURF) Symposium
The extracellular matrix (ECM) is composed of many different proteins excreted by cells and is believed to play a very important role in development as well as regeneration and wound healing. In this research, a method to determine the ECM’s effect on the migration of muscle progenitor cells into the mammalian limb bud was investigated. It has traditionally been difficult to obtain in vivo images of the limb bud, due to the difficulty of maintaining embryos in culture and limitations of imaging techniques. In this study, we have worked on optimizing the culture conditions to allow growth of mouse embryos …
Visualization Of Complex Flow Patterns In Angiotensin Ii-Induced Dissecting Murine Abdominal Aortic Aneurysms With High Frequency Ultrasound,
2013
Purdue University
Visualization Of Complex Flow Patterns In Angiotensin Ii-Induced Dissecting Murine Abdominal Aortic Aneurysms With High Frequency Ultrasound, Hilary D. Schroeder, Alexa A. Yrineo, Amy E. Bogucki, Craig J. Goergen
The Summer Undergraduate Research Fellowship (SURF) Symposium
Abdominal aortic aneurysm (AAA) rupture is a common cause of mortality in the United States. Current treatments are only employed once the risk of rupture outweighs the risks associated with surgery. Murine models have been developed to characterize AAA pathogenesis in the hope that new treatments will be developed. For this study, angiotensin II (AngII) was infused subcutaneously into apolipoprotein E-deficient (ApoE-/-) mice using an osmotic mini-pump over 28 days. ApoE-/- mice (16-week-old, 3 females, 2 males) were imaged using a VisualSonics Vevo 2100 high frequency ultrasound before pump implantation and 3, 7, 14, 21, and 27 …
Image Skeletal Muscle Progenitors In Situ To Investigate How The Ecm Composition Regulates Musculoskeletal Assembly,
2013
University of Missouri
Image Skeletal Muscle Progenitors In Situ To Investigate How The Ecm Composition Regulates Musculoskeletal Assembly, Andrew L. Schilb, Sarah Calve
The Summer Undergraduate Research Fellowship (SURF) Symposium
Regenerative medicine has difficulty with the human body’s inability to functionally repair tissues lost as a result of disease or serious accident. Through tissue engineering, there has been development of various scaffolding with the purpose of enhancing skeletal muscle regrowth and functionality. The scaffolds are typically constructed from artificial polymers or decellularized extracellular matrix (ECM) that mimics adult tissue. These standardized scaffolds are hindered though by the host since tissue engineers have not taken into account of how the composition musculoskeletal ECM during tissue repair is dramatically different than that of a homeostatic adult. Now green fluorescent protein positive (GFP+) …
The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro,
2013
Purdue University
The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro, Caleb J. Mcdaniel, Sarah Calve
The Summer Undergraduate Research Fellowship (SURF) Symposium
To improve the treatment of musculoskeletal injuries, a better understanding of the transitional environment in which progenitor cells form mature musculoskeletal constructs is necessary. This need arises because injury repair requires restructuring of tissue, similar to the initial tissue construction that occurs during embryonic development by progenitor cells. Differences in both the biochemical and mechanical environments between a transitional and a differentiated state are known to take place, but how these differences affect cell behavior had not yet been characterized in mammalian tendon cells. In order to investigate this, we have determined the effects of exogenous extracellular matrix and the …
Wireless Myoelectric Sensor Minimization And Packaging,
2013
University of Iceland
Wireless Myoelectric Sensor Minimization And Packaging, Ásbjörg Einarsdóttir, Pedro Irazoqui Dr.
The Summer Undergraduate Research Fellowship (SURF) Symposium
Many people suffer from amputation, which affects their lives severely by disabling them from doing chores in their daily life as well as chores related to work and leisure. For the last years, prosthetics’ development has been fast and the devices that are being used now are a miracle compared to what has been used before. But still, the battle is not over yet. Although scientists have techniques and devices to use nerve residues from the amputated limb to control the prosthetic, smaller devices that can detect the signals from those nerves better need to be developed. In this research …
Toward An Optogenetic Autonomous Nerve Control (Oanc) System,
2013
Purdue University
Toward An Optogenetic Autonomous Nerve Control (Oanc) System, Malika S. Datta, Matthew Ward, Steven Lee, Kevin Seburn, Pedro Irazoqui
The Summer Undergraduate Research Fellowship (SURF) Symposium
Optogenetics is a developing field in neuroscience, where nerves are stimulated through optical instead of electrical signals, allowing for a more selective action of nerve populations [Aravanis et al, 2007]. In the context of electrical stimulation, the autonomous nerve control (ANC) system has been used successfully, first to map the response of different nerve fibers to create a Nerve Activation Profile, and then to use this profile in recruiting specific nerve fibers in a controlled way [MP Ward et al, unpublished manuscript in preparation]. The objective of the present project is to apply the ANC system to optical stimulation thus …
Inkjet Printing Of Polarized Yeast Cells,
2013
Purdue University
Inkjet Printing Of Polarized Yeast Cells, Xiuyuan Yang, Kari Clase
The Summer Undergraduate Research Fellowship (SURF) Symposium
The motivation is to applying engineering knowledge to develop 3D bio-printing in inkjet printer (first stage--monolayer). To achieve the goal, there are three problems to solve. First, we have to figure out regulation of growth of target cells; inability to regulate the location and pattern of growing cells make us even unable to build 3D printer in the direct way. Second problem is how to protect of yeast cells from high temperature and viscous force when printing. The third issue is how to modify the inkjet printer especially the feeding system in order to implement printing on other materials rather …
Adhesive Elastomeric Proteins,
2013
Purdue University
Adhesive Elastomeric Proteins, Haefa Mansour, Julie Liu
The Summer Undergraduate Research Fellowship (SURF) Symposium
Sutures and staples commonly used to close surgical wounds tend to be much stiffer than the surrounding tissue, often resulting in external tissue damage. Surgical adhesives provide a promising alternative to these sutures and staples. Ideal surgical adhesives are biocompatible, able to set well and remain sticky in moist conditions, possess strong adhesive and cohesive properties, and exhibit mechanical properties that mimic those of the surrounding tissue. Unfortunately, the adhesives available today are unable to satisfactorily meet all of these criteria. We are utilizing protein engineering techniques to design, create, and test a new surgical adhesive that combines the adhesive …
A Quantitative Analysis Of A Paper-Based, Laser-Defined, Oxygen-Generating Platform For Chronic Wounds,
2013
Rice University
A Quantitative Analysis Of A Paper-Based, Laser-Defined, Oxygen-Generating Platform For Chronic Wounds, Tiffany L. Huang, Babak Ziaie
The Summer Undergraduate Research Fellowship (SURF) Symposium
Chronic wounds affect 6.5 million patients a year while consuming US$25 billion in health care costs (Sen 2009 Wound Repair Regen.). Despite advances in wound management therapies, modern treatment for chronic wounds still requires continual professional attention and expensive equipment, posing serious practical and financial burdens for the regular patient. To provide an alternative solution, we are developing a low-cost smart bandage platform that integrates actuators and sensors to monitor and treat chronic wounds. One component of the integrated platform is an oxygen-generating module. It is a polydimethylsiloxane (PDMS) based microfluidic device fabricated on a parchment paper substrate that …
Development Of Non-Invasive In Vivo Ultrasound Imaging Techniques For Elastase-Induced Experimental Abdominal Aortic Aneurysms,
2013
Purdue University
Development Of Non-Invasive In Vivo Ultrasound Imaging Techniques For Elastase-Induced Experimental Abdominal Aortic Aneurysms, Alexa A. Yrineo, Elizabeth A. Nunamaker, Hilary D. Schroeder, Amy E. Bogucki, Craig J. Goergen
The Summer Undergraduate Research Fellowship (SURF) Symposium
Abdominal aortic aneurysms (AAAs) are pathological dilations of the aorta which are associated with significant morbidity and mortality. The underlying mechanisms that cause this inflammatory disease are not fully understood and thus, are currently under investigation. In the hopes of preventing disease progression, rodent models that mimic the human condition have been developed to provide insight into the pathogenesis of AAAs. In this study, porcine pancreatic elastase (0.44 U; Sigma-Aldrich) was infused into the infrarenal aortas of male, Sprague Dawley rats to induce aneurysms. To perform the surgery, temporary ligatures were placed around proximal and distal sections of the abdominal …
