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Full-Text Articles in Engineering

Fluidic Control With Wax Valves For Paper-Based Diagnostics, Emilie I. Newsham, Elizabeth A. Phillips, Katherine N. Clayton, Jacqueline C. Linnes Aug 2018

Fluidic Control With Wax Valves For Paper-Based Diagnostics, Emilie I. Newsham, Elizabeth A. Phillips, Katherine N. Clayton, Jacqueline C. Linnes

The Summer Undergraduate Research Fellowship (SURF) Symposium

Paper-fluidic devices are a common platform for point-of-care disease detection in under-resourced areas because of their low cost and minimal instrumentation requirements. Limited fluidic control in paper-fluidic devices has hindered the incorporation of multistep reactions that are necessary for more sensitive disease detection. One potential fluidic control mechanism is the incorporation of thermally actuated wax valves to separate assay stages. Such valving would expand the detection capabilities of these devices by permitting fluid obstruction for sustained reactions and facilitating controlled volume release within a fully-automated, self-contained device. Despite the potential to exploit wax valves for innovative paper-fluidic diagnostics, a thorough, …


Magnetically Actuated Cell Stretching Platform To Induce Phenotypic Changes In Metastatic Cells, Yong Gyun Cho, Hyunsu Park, Hyowon Lee, Sarah Libring Aug 2018

Magnetically Actuated Cell Stretching Platform To Induce Phenotypic Changes In Metastatic Cells, Yong Gyun Cho, Hyunsu Park, Hyowon Lee, Sarah Libring

The Summer Undergraduate Research Fellowship (SURF) Symposium

Although metastasis is responsible for about 90% of cancer deaths, only few in vitro models can be used to evaluate dynamic behaviors of metastatic cancer cells. Many studies have shown that mechanical stimuli can trigger various cellular responses such as gene and protein expression, which could lead to changes in cellular phenotype. Similarly, metastasized breast cancer cells in the lung tissue are constantly stretched by cyclic mechanical stress due to breathing, which alters cellular morphology and proliferation state. Such transitions can make the secondary tumors resistant to the chemotherapy used to effectively treat the primary tumors. In this work, we …


Neural Coding Of An Auditory Pitch Illusion, Maria Alejandra Barrera, Mark Sayles, Ravinderjit Singh Aug 2018

Neural Coding Of An Auditory Pitch Illusion, Maria Alejandra Barrera, Mark Sayles, Ravinderjit Singh

The Summer Undergraduate Research Fellowship (SURF) Symposium

Pitch is an important perceptual dimension in audition, supporting auditory object segregation, melody recognition and lexical distinction. Huggins’ pitch, for example, is a phenomenon evoked by two sources of broadband noise presented binaurally with an inter-aural phase shift over a narrow frequency band. Huggins’ pitch and other dichotic pitches have been studied extensively using perceptual experiments. Several models have been proposed to explain and predict the perception of pitch; however, no studies have tried to record in vivo neuron responses to Huggins’ pitch (HP) nor have tried to explain how the HP is coded by neurons. The existence of pitches …


Tissue Clearing As A Mechanism To Identify Changes In Fibronectin Structure During Breast Cancer Metastasis, Maryam Nuru, Kelsey Hopkins, Luis Solorio Aug 2018

Tissue Clearing As A Mechanism To Identify Changes In Fibronectin Structure During Breast Cancer Metastasis, Maryam Nuru, Kelsey Hopkins, Luis Solorio

The Summer Undergraduate Research Fellowship (SURF) Symposium

With metastasis accounting for approximately 90% of breast cancer deaths and an alarming number of over 300,000 new breast cancer cases to be diagnosed by the end of 2018, there is growing need to understand the process of breast cancer. Changes in the extracellular matrix (ECM) of the tumor microenvironment play an essential role in this deadly tumor progression. Specifically, the glycoprotein fibronectin (FN), has been identified to be up-regulated in patients with worse clinical outcomes. During tumor progression fibronectin undergoes conformational changes that aid in metastatic dissemination. In order to analyze the dynamic changes in FN expression and evaluate …


High-Throughput Nanoliter Dispensing Device For Biological Applications, Cole Reynolds, Euiwon Bae Dr., J Paul Robinson Dr. Aug 2018

High-Throughput Nanoliter Dispensing Device For Biological Applications, Cole Reynolds, Euiwon Bae Dr., J Paul Robinson Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Pathogen identification is a field that can contribute largely to the prevention of the spreading of illness and disease. In the past, pathogen identification has been a long and arduous process due to the time-consuming processes and steps that requires technician’s time and effort. With new technologies emerging however, screening of bacteria colonies can be done in a quick and high-throughput way. The problem is that using the current methods, bacteria cannot be transferred to petri dishes fast enough to keep up with the new screening methods. The current study focuses on exploring different methods to create an ergonomic device …


Creating A Mammary Duct Model To Study The Effects Of Cancer Heterogeneity On Tumor Metastasis, Megan Hofstetter, Mazin Hakim, Luis Solorio Aug 2018

Creating A Mammary Duct Model To Study The Effects Of Cancer Heterogeneity On Tumor Metastasis, Megan Hofstetter, Mazin Hakim, Luis Solorio

The Summer Undergraduate Research Fellowship (SURF) Symposium

During tumor progression, the process of clonal evolution gives rise to a variety of cell subpopulations that cause differential sensitivity to drugs and give rise to cell populations with the ability to metastasize, there are many mouse models available that can be used to study tumor progression and metastasis. However, there is a lack of models to study the effect of tumor heterogeneity using human cancers. Xenograft based systems require the use of immunodeficient mice, which limits the use of the model to evaluate microenvironmental factors involved in metastatic dissemination. Humanized mouse models with established human immune systems have been …


Non-Invasive Diagnostic Measures Of Sensorineural Hearing Loss In Chinchillas, Hannah M. Ginsberg, Satyabrata Parida, Michael G. Heinz Aug 2018

Non-Invasive Diagnostic Measures Of Sensorineural Hearing Loss In Chinchillas, Hannah M. Ginsberg, Satyabrata Parida, Michael G. Heinz

The Summer Undergraduate Research Fellowship (SURF) Symposium

According to the World Health Organization, disabling hearing loss affects nearly 466 million people worldwide. Sensorineural hearing loss (SNHL), which is characterized as damage to the inner ear (e.g., cochlear hair cells) and/or to the neural pathways connecting the inner ear and brain, accounts for 90% of all disabling hearing loss. More concerning is that significant perceptual and physiological aspects of SNHL remain “hidden” from standard clinical diagnostics. Hidden hearing loss (HHL) manifests as the inability to understand speech in loud, noisy environments (e.g., listening in a noisy restaurant) despite a normal audiogram (i.e., normal detection of soft sounds). Recently, …


Method Validation Of Functional Magnetic Resonance Imaging And Electrophysiological Recording To Investigate Mechanisms Of Vagus Nerve, Christina L. Hendren, Jiayue Cao, Zhongming Liu Aug 2018

Method Validation Of Functional Magnetic Resonance Imaging And Electrophysiological Recording To Investigate Mechanisms Of Vagus Nerve, Christina L. Hendren, Jiayue Cao, Zhongming Liu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Vagus nerve stimulation (VNS) is used clinically to treat epilepsy and depression, but its mechanism of action is unknown. Useful techniques to study this are functional magnetic resonance imaging (fMRI) and the local field potential (LFP). fMRI relies on oxygen use in the brain to show areas where neurons are active. The LFP is an electrical signal created by neuron action potentials and other current moving across cell membranes. The most information can be gained when the two methods are used simultaneously, however, this is difficult to do. This study seeks to validate the technique of fMRI-LFP as applied to …


Flow Chamber For Confocal Tracking Of Particles In Bone, Brennan Flannery, Russell Main, Xiaoyu Xu Aug 2018

Flow Chamber For Confocal Tracking Of Particles In Bone, Brennan Flannery, Russell Main, Xiaoyu Xu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Interstitial fluid flow in the lacunar-canalicular system (LCS) of bone is recognized as a potential regulator of bone remodeling. Movement of fluid across bone cells called osteocytes regulates gene expression that leads to either bone formation or resorption. Interstitial fluid moves in response to bone loading during daily activity, and bone growth occurs to compensate for these loads, affecting bone shape and strength. While interstitial fluid flow is thoroughly studied using computational models, there is a critical need to study flow in real bone samples with imaging techniques. Flow velocities determined from imaging will be more accurate than computational models …


Mechanically Assisted Electrochemical Degradation Of Alumina-Tic Composites, Hetal Umesh Maharaja, Guigen Zhang Aug 2018

Mechanically Assisted Electrochemical Degradation Of Alumina-Tic Composites, Hetal Umesh Maharaja, Guigen Zhang

Publications

Alumina-TiC composite material is a tough ceramic composite with excellent hardness, wear resistance and oxidation resistance in dry and high-temperature conditions. In aqueous conditions, however, it is likely to be electrochemically active facilitating charge transfer processes due to the conductive nature of TiC. For application as an orthopedic biomaterial, it is crucial to assess the electrochemical behavior of this composite, especially under a combined mechanical and electrochemical environment. In this study, we examined the mechanically assisted electrochemical performance of alumina-TiC composite in an aqueous environment. The spontaneous electrochemical response to brushing abrasion was measured. Changes in the magnitude of electrochemical …


Detection Of Molecular Biomarkers Involved In The Induction Of Emt, Migration And Invasion, And Drug Resistance In Breast Cancer Cells In 3d Confinement, Tamara Nicole Hill Aug 2018

Detection Of Molecular Biomarkers Involved In The Induction Of Emt, Migration And Invasion, And Drug Resistance In Breast Cancer Cells In 3d Confinement, Tamara Nicole Hill

Bioengineering Dissertations - Archive

Standard-of-care regimes for cancer treatment have become more effective and sophisticated over the last decade due to research developments which facilitate specific targeting of treatments to certain cancers, and the ability to provide specialized care to cancer patients. However, cancer treatments overall still fall short of preventing spread of disease from the primary tumor to secondary sites where they settle and form new more aggressive tumors. It is this stage of disease progression which results in the majority of cancer deaths. The long-term goal of this research is to develop a system for the effective high throughput screening of chemotherapeutic …


Fabrication And In Vitro Characterization Of An Implant For The Detection Of Metastatic Cancer Cells, Carlos Martin Cantu Aug 2018

Fabrication And In Vitro Characterization Of An Implant For The Detection Of Metastatic Cancer Cells, Carlos Martin Cantu

Bioengineering Theses - Archive

Greater than 90% of cancer related deaths are due to metastasis (Hayes & Wicha, 2011). Since current conventional techniques detect the disease by the time that it has become systemic, our lab has developed a hydrogel based cancer trap that can attract metastatic cancer cells via cytokine release. However, for continual monitoring and accessibility to the gel, an implant is needed for delivery, retention, and retrieval of the gel. The research undergone in this thesis seeks to develop such a method. Namely, the objective was to develop a polylactide (PLA) based implant that is capable of delivering and retaining a …


Development Of Mussel Inspired Nanocomposite Adhesives For Biomedical Applications, Nikhil Pandey Aug 2018

Development Of Mussel Inspired Nanocomposite Adhesives For Biomedical Applications, Nikhil Pandey

Bioengineering Dissertations - Archive

Popular bioadhesives, such as fibrin, cyanoacrylate and albumin–glutaraldehyde-based materials, have been applied for clinical applications in wound healing, drug delivery, and bone and soft tissue engineering; however, their performances are limited by weak adhesion strength and rapid degradation. The long-term goal of this research is to develop a strong tissue adhering nanocomposite for tissue interfacing and wound healing applications. We begin by developing a mussel-inspired, nanocomposite–based, biodegradable tissue adhesive by blending poly (lactic-co-glycolic acid) (PLGA) or N-hydroxysuccinimide modified PLGA nanoparticles (PLGA-NHS) and polydopamine nanoparticles with mussel-inspired polymers. Adhesive strength measurement of the nanocomposites on porcine skin-muscle constructs revealed that the …


Nanoparticles For Gene Therapy And Protein Delivery To Induce Angiogenesis As An Alternative Treatment For Peripheral Arterial Disease, Linda Christellia Noukeu Aug 2018

Nanoparticles For Gene Therapy And Protein Delivery To Induce Angiogenesis As An Alternative Treatment For Peripheral Arterial Disease, Linda Christellia Noukeu

Bioengineering Dissertations - Archive

Peripheral arterial disease (PAD) is defined as a slow, progressive disorder of the lower extremity arterial vessels characterized by chronic narrowing that often results in occlusion and is associated with loss of functional capacity. Although the PAD occurrence rate is increasing in the elderly population, outcomes with current treatment strategies are suboptimal. Hence, there is an urgent need to develop new technologies that overcome limitations of traditional modalities for PAD detection and therapy. In this research, nanoparticles have been developed and used as carriers for various therapeutic agents to treat PAD. In particular, via protein/gene delivery, we developed and formulated …


An Enhancement Of Light Reflectance Spectroscopy As A Modality For The Detection Of Positive Surgical Margins In Radical Prostatectomy, Zengxing Pang Aug 2018

An Enhancement Of Light Reflectance Spectroscopy As A Modality For The Detection Of Positive Surgical Margins In Radical Prostatectomy, Zengxing Pang

Bioengineering Theses - Archive

Light Reflectance Spectroscopy (LRS) is an imaging method that has shown increasingly promising evidence in its ability to detect various forms of cancer tissues. Our previous studies have illustrated the LRS modality’s capacity to differentiate normal and cancerous prostate tissues, specifically in its effectiveness in distinguishing cancer tissues classified 4+3 and 4+4 in Gleason Score. Despite having shown sufficient sensitivity and specificity towards prostate cancer detection, the pre-existing imaging system remains impractical for its intended clinical application of detecting positive surgical margins during prostatectomy. Two of the biggest challenges in the current equipment include lack of mobility and slow data …


Feature-Based Discretization Of A Turbine Disk For Probabilistic Risk Assessment, Michael Thomas, Jace Carter, Lloyd Matson, Tarun Goswami Aug 2018

Feature-Based Discretization Of A Turbine Disk For Probabilistic Risk Assessment, Michael Thomas, Jace Carter, Lloyd Matson, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

There is an economic need to extend the useful life of jet engine rotors. Retirement-for-Cause (RFC) is a lifing method that allows for the continued operation of components passed traditional life limits. Under RFC, an extension of damage tolerance, components are deemed safe for a further service interval using non-destructive inspections (NDI) for crack like defe cts. As components are kept in-service beyond their designed service life it is essential that the probability of failure (POF), or risk, of continued service is known. Under current FAA rotor design certification practices the component POF is analyzed using a probabilistic framework focused …


Inverse Dynamic Analysis Of Acl Reconstructed Knee Joint Biomechanics During Gait And Cycling Using Opensim, Megan V. Pottinger Aug 2018

Inverse Dynamic Analysis Of Acl Reconstructed Knee Joint Biomechanics During Gait And Cycling Using Opensim, Megan V. Pottinger

Master's Theses

ACL (anterior cruciate ligament) injuries of the knee joint alter biomechanics and may cause abnormal loading conditions that place patients at a higher risk of developing osteoarthritis (OA). There are multiple types of ACL reconstruction (ACLR), but all types aim to restore anterior tibial translation and internal tibial rotation following surgery. Analyzing knee joint contact loads provide insight into the loading conditions following ACLR that may contribute to the long-term development of OA. Ten ACLR subjects, who underwent the same reconstruction, performed gait and cycling experiments while kinematic and kinetic data were collected. Inverse dynamic analyses were performed on processed …


Antimicrobial Efficacy And Safety Of A Novel Gas Plasma-Activated Catheter Lock Solution, Sudhir Bhatt, Poonam Mehta, Chen Chen, Dayle A. Daines, Leonard A. Mermel, Hai-Lan Chen, Michael G. Kong Aug 2018

Antimicrobial Efficacy And Safety Of A Novel Gas Plasma-Activated Catheter Lock Solution, Sudhir Bhatt, Poonam Mehta, Chen Chen, Dayle A. Daines, Leonard A. Mermel, Hai-Lan Chen, Michael G. Kong

Bioelectrics Publications

Antimicrobial lock solutions are important for prevention of microbial colonization and infection of long-term central venous catheters. We investigated the efficacy and safety of a novel antibiotic-free lock solution formed from gas plasma-activated disinfectant (PAD). Using a luminal biofilm model, viable cells of methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Candida albicans in mature biofilms were reduced by 6 to 8 orders of magnitude with a PAD lock for 60 min. Subsequent 24-h incubation of PAD-treated samples resulted in no detectable regrowth of viable bacteria or fungi. As a comparison, the use of a minocycline-EDTA-ethanol lock solution for 60 …


Time Evolution Of Ecog Network Connectivity In Patients With Refractory Epilepsy, Michael J. Selesko Aug 2018

Time Evolution Of Ecog Network Connectivity In Patients With Refractory Epilepsy, Michael J. Selesko

Masters Theses

Epilepsy is a common neurological disorder that causes recurrent, unprovoked seizures. Focal, refractory epilepsy is characterized by seizures that start in a specific area in the brain and do not respond to antiepileptic medication. This study was conducted to characterize the connectivity of the focal brain region where seizures originate, known as the epileptogenic zone. Connectivity was measured from electrocorticogram (ECoG) recordings, during seizure events, using information theoretic measures mutual information (MI) and (TE). MI is the amount of information shared between two discrete random variables. TE is the directed information transfer between two discrete random variables. MI provides information …


Identification Of The Seizure Onset Zone By Auto-Regressive Model Residual Modulation Applied To Intracranial Eeg And Its Correlation To Channels With High Preponderances Of Detected Hfos, Allison L. Rogutich Aug 2018

Identification Of The Seizure Onset Zone By Auto-Regressive Model Residual Modulation Applied To Intracranial Eeg And Its Correlation To Channels With High Preponderances Of Detected Hfos, Allison L. Rogutich

Masters Theses

The objective of this thesis was to examine the ability of the Autoregressive Model Residual Modulation (ARRm) method to identify the Seizure Onset Zone (SOZ) in intracranial electroencephalogram (iEEG) of patients with refractory epilepsy. Patients who have not become seizure free after multiple trials of antiepileptic drugs (AEDs) may seek treatment through epilepsy surgery. Cortical electrodes are implanted directly on the cerebral cortex, then iEEG is collected. A specialized neurologist reviews the iEEG, then in consultation with the neurosurgeon, the SOZ is determined and areas of the brain may be chosen for resection. The success rate of epilepsy surgery varies, …


Gold Nanoparticles For Stem Cell Delivery In Myocardial Infarction: Analysis Of Toxicity And Development Of A Cell Culture Platform For Use In An In-Vitro Model Of Mi-Associated Ischemia/Reperfusion, Jeffrey Curran Henson Aug 2018

Gold Nanoparticles For Stem Cell Delivery In Myocardial Infarction: Analysis Of Toxicity And Development Of A Cell Culture Platform For Use In An In-Vitro Model Of Mi-Associated Ischemia/Reperfusion, Jeffrey Curran Henson

Graduate Theses and Dissertations

In this work, the potential for PEGylated gold nanoparticles for use as a platform for stem cell delivery in treatment of myocardial infarction (MI) is preliminarily investigated. Cardiovascular disease is currently the leading cause of death worldwide, with majority of mortality resulting from coronary artery disease and associated MI. The ensuing ischemic conditions resulting from MI cause substantial heart muscle tissue loss and scarring in the heart. Adverse tissue remodeling creates a significant loss in heart function that can result in the formation of cardiac hypertrophy, ventricular dilation and arrythmias. The long-term prognosis of patients who have suffered MI is …


Evaluation Of A Solar Powered Variable Flow Tail Water Recovery System For Furrow Irrigation, Vaishali Kandpal Aug 2018

Evaluation Of A Solar Powered Variable Flow Tail Water Recovery System For Furrow Irrigation, Vaishali Kandpal

Graduate Theses and Dissertations

Furrow irrigation is a very common irrigation method for growing crops like soybean, cotton and corn in Arkansas. A major portion of this irrigation water is lost as runoff from the field significantly reducing the irrigation application efficiency. There are various methods of improving irrigation efficiency and one of the methods is using tail-water recovery. A tail-water recovery system utilizes tail-water recovery ditches or pits to collect tail-water which can be re-used for irrigation. However, this method is very labor intensive and has been found to be economically non-feasible for some farms in the past research studies. In order to …


Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller Aug 2018

Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller

Electronic Theses and Dissertations

The inherent heterogeneity of tumor tissue presents a major challenge to nanoparticle-medicated drug delivery. This heterogeneity spans from the molecular to the cellular (cell types) and to the tissue (vasculature, extra-cellular matrix) scales. Here we employ computational modeling to evaluate therapeutic response as a function of vascular-induced tumor tissue heterogeneity. Using data with three-layered gold nanoparticles loaded with cisplatin, nanotherapy is simulated with different levels of tissue heterogeneity, and the treatment response is measured in terms of tumor regression. The results show that tumor vascular density non-trivially influences the nanoparticle uptake and washout, and the associated tissue response. The drug …


Shipboard Design And Fabrication Of Custom 3d-Printed Soft Robotic Manipulators For The Investigation Of Delicate Deep-Sea Organisms, Daniel M. Vogt, Kaitlyn P. Becker, Brennan T. Phillips, Moritz A. Graule, Randi D. Rotjan, Timothy M. Shank, Erik E. Cordes, Robert J. Wood, David F. Gruber Aug 2018

Shipboard Design And Fabrication Of Custom 3d-Printed Soft Robotic Manipulators For The Investigation Of Delicate Deep-Sea Organisms, Daniel M. Vogt, Kaitlyn P. Becker, Brennan T. Phillips, Moritz A. Graule, Randi D. Rotjan, Timothy M. Shank, Erik E. Cordes, Robert J. Wood, David F. Gruber

Publications and Research

Soft robotics is an emerging technology that has shown considerable promise in deep-sea marine biological applications. It is particularly useful in facilitating delicate interactions with fragile marine organisms. This study describes the shipboard design, 3D printing and integration of custom soft robotic manipulators for investigating and interacting with deep-sea organisms. Soft robotics manipulators were tested down to 2224m via a Remotely-Operated Vehicle (ROV) in the Phoenix Islands Protected Area (PIPA) and facilitated the study of a diverse suite of soft-bodied and fragile marine life. Instantaneous feedback from the ROV pilots and biologists allowed for rapid re-design, such as adding ªfingernailsº, …


Rotary Pump Speed Modulation To Produce Pulsatile Flow And Ventricular Volume Unloading., Connor Joseph Smith Aug 2018

Rotary Pump Speed Modulation To Produce Pulsatile Flow And Ventricular Volume Unloading., Connor Joseph Smith

Electronic Theses and Dissertations

Background: Continuous-flow (CF) left ventricular assist devices (LVADs) have gained widespread clinical acceptance as a treatment option for advanced heart failure (HF); however, they have also been associated with an increased risk of adverse events, including gastrointestinal bleeding, aortic insufficiency, and hemorrhagic stroke. It has been hypothesized that the increase in adverse event incidence may be due in part to diminished vascular pulsatility and high shear stress when CF-LVADs are operated at fixed speeds. Previous studies have shown that pump speed modulation generates greater levels of pulsatility in rotary pumps than when operated at fixed speeds. The objective of this …


Uncoupling Fermentative Synthesis Of Molecular Hydrogen From Biomass Formation In Thermotoga Maritima, Raghuveer Singh, Derrick White, Yaşar Demirel, Robert Kelley, Kenneth Noll, Paul H. Blum Aug 2018

Uncoupling Fermentative Synthesis Of Molecular Hydrogen From Biomass Formation In Thermotoga Maritima, Raghuveer Singh, Derrick White, Yaşar Demirel, Robert Kelley, Kenneth Noll, Paul H. Blum

Department of Chemical and Biomolecular Engineering: Faculty Publications

When carbohydrates are fermented by the hyperthermophilic anaerobe Thermotoga maritima, molecular hydrogen (H2) is formed in strict proportion to substrate availability. Excretion of the organic acids acetate and lactate provide an additional sink for removal of excess reductant. However, mechanisms controlling energy management of these metabolic pathways are largely unexplored. To investigate this topic, transient gene inactivation was used to block lactate production as a strategy to produce spontaneous mutant cell lines that overproduced H2 through mutation of unpredicted genetic targets. Single-crossover homologous chromosomal recombination was used to disrupt lactate dehydrogenase (encoded by ldh) with …


Studying The Applicability Of Biostimulated Calcite Precipitation In Stabilizing Expansive Soils, Md Touhidul Islam Aug 2018

Studying The Applicability Of Biostimulated Calcite Precipitation In Stabilizing Expansive Soils, Md Touhidul Islam

Boise State University Theses and Dissertations

Of the four types of soils, clays are often associated with issues related to low bearing capacity, high compressibility, swelling and shrinking nature. For example, expansive soils swell and shrink with moisture ingress and digress and are prevalent in several parts of the world causing billions of dollars in damages annually to various civil infrastructures. Several ground improvement techniques such as chemical stabilization, deep soil mixing, moisture barriers, and others were employed to counteract these soils. However, these methods are impractical in certain situations and unsustainable in others due to their economic and environmental impacts. Microbiological treatment of soils could …


Development And Optimization Of A Produced Water, Biofilm Based Microalgae Cultivation System For Biocrude Conversion With Hydrothermal Liquefaction, Benjamin L. Peterson Aug 2018

Development And Optimization Of A Produced Water, Biofilm Based Microalgae Cultivation System For Biocrude Conversion With Hydrothermal Liquefaction, Benjamin L. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extraction of oil and gas in Utah’s Uintah Basin results in large quantities of wastewater, or produced water, with nutrients and residual organic chemical that represent a significant resource for producing energy-related and value-added products. Produced water was obtained as a biomass producing nutrient source from industries operating in Utah’s Uintah Basin. Within the Uintah Basin (defined as Uintah and Duchesne Counties within Utah) approximately 93 million barrels of water were produced in 2013 while only 11% of the water was disposed of through evaporation, with the national average at 2%. The rest is reinjected into the subsurface.

The goal …


Novel Methods To Produce Large Recombinant Spider Silk Proteins Via Polymerization, Nathan L. Hebert Aug 2018

Novel Methods To Produce Large Recombinant Spider Silk Proteins Via Polymerization, Nathan L. Hebert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider silk has long been a subject of scientific research due to its remarkable mechanical properties. Until recently, there has been no way to effectively obtain spider silk except by harvesting it from individual spiders. With advances in technology, the genes that code for the individual spider silk proteins have been isolated and genetically engineered into other hosts to produce recombinant spider silk proteins (rSSp) of varying sizes, Larger rSSp have correspondingly greater mechanical properties in any resulting materials. Using current production methods, larger rSSp cannot be produced in commercially viable quantities while simultaneously being economically viable. The current production …


Biofidelic Piezoresistive Sandwich Composites, Nengda Jiang Aug 2018

Biofidelic Piezoresistive Sandwich Composites, Nengda Jiang

Doctoral Dissertations and Master's Theses

Silicone based biofidelic surrogates are being used in many biomedical applications; e.g. to understand the body injury mechanisms, evaluate protective equipment like helmets and armors. Apart from matching the mechanical behavior of bodily tissues, there is an increasing requirement for these materials to be electrically conductive and piezoresistive to facilitate direct instrumentation. Carbon nanotubes (CNTs) are a possible filler to impart electrical conductivity and piezoresistivity to silicone biofidelic materials. A sandwich structure of silicone and CNT sheet, comprising two dielectric facesheets and a highly conductive core layer has added advantages of raising the dielectric permittivity and suppressing dielectric loss.

In …