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Biodegradation Of Cresols Using Pseudomonas Putida Immobilized In Poly Vinyl Alcohol (Pva) Gel, Riham Mohamed Sorkatti Abu Bakr

Theses

The characteristics and viability of polyvinyl alcohol (PVA) as a support material for biomass immobilization and utilization for the biodegradation of cresols have been evaluated. PVA gel pellets were prepared by repeated freezing-thawing method using different PVA compositions. The porous structures of the PVA pellets were examined using a Compound Microscope and SEM and revealed that the matrix structure and pore size distribution were affected by PVA composition. Mechanical properties of the PVA gel were also characterized to evaluate the PVA integrity as a matrix for immobilizing microbial cells and found to be dependent on the PVA mass composition. The …

A Study On Countermeasures Against Steganography: An Active Warden Approach, Qilin Qi

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

Digital steganography is a method used for hiding information in digital images. It can be used for secure communication. There have been many robust digital steganography methods invented in recent decades. The steganographic message can be inserted in multimedia cover signal such as audio, image and video. However, this technique also may be used by malicious users to transmit dangerous information through the Internet beyond the control of security agencies. How to detect and/or block potentially dangerous information transmission on the Internet through billions of multimedia files while not affecting innocent multimedia communications becomes a challenging problem. Existing steganalysis methods …

Analysis Of Social Networks In A Virtual World, Gregory Thomas Stafford

Graduate Theses and Dissertations

As three-dimensional virtual environments become both more prevalent and more fragmented, studying how users are connected via their avatars and how they benefit from the virtual world community has become a significant area of research. An in-depth analysis of virtual world Social networks is needed to evaluate how users interact in virtual worlds, to better understand the impact of avatar Social networks on the virtual worlds, and to improve future online Social networks.

Our current efforts are focused on building and exploring the Social network aspects of virtual worlds. In this thesis, we build a Social network of avatars based …

Zinc Oxide Nanorod Based Ultraviolet Detectors With Wheatstone Bridge Design, Arun Vasudevan

Graduate Theses and Dissertations

This research work, for the first time, investigated metal semiconductor-metal (MSM) zine oxide (ZnO) nanorod based ultra-violet (UV) detectors having a Wheatstone bridge design with a high

responsivity at room temperature and above, as well as a responsivity that was largely independent of the change in ambient conditions. The ZnO nanorods which acted as the sensing element of the detector were grown by a chemical growth technique. Studies were conducted to determine the effects on ZnO nanorod properties by varying the concentration of the chemicals used for the rod growth. These studies showed how the rod diameter and the deposition …

The Development Of A Traumatic Brain Injury Bioreactor, Zachery Heller

Graduate Theses and Dissertations

Approximately 1.7 million Americans experience a traumatic brain injury (TBI) each year. Concussive injuries are a subset of TBI in which blows to the head cause the brain to collide against the interior of the skull. Damage to the neurons, supporting cells, and surrounding extra cellular matrix resulting from these collisions can lead to permanent physical, cognitive, and psychological impairment. We believe the prevalence and clinical significance of concussive injures warrants research investment. To study brain injury following TBI, in vivo models have been the gold standard for TBI experiments. Although a valuable research alternative, animals are expensive, raise ethical …

Development And Evaluation Of Chitosan Particle Based Antigen Delivery Systems For Enhanced Antigen Specific Immune Response, Bhanuprasanth Koppolu

Graduate Theses and Dissertations

Particle-based vaccine delivery systems are under exploration to enhance antigen-specific immunity against safe but poorly immunogenic polypeptide antigens. Chitosan is a promising biomaterial for antigen encapsulation and delivery due to its ability to form nano- and microparticles in mild aqueous conditions thus preserving the antigenicity of loaded polypeptides. The objective of this work is to develop a chitosan particle based antigen delivery system for enhanced vaccine response. Chitosan particle sizes, which ranged from 300 nm to 3 ìm, were influenced by chitosan concentration, chitosan molecular weight and addition rate of precipitant salt. The composition of precipitant salt played a significant …

Heat Of Combustion Of Algae For Use In A Diesel Engine, Cassia Diane Davis

Masters Theses and Doctoral Dissertations

With nearly a quarter of the world’s population living without any access to electricity or modern energy, strategies for providing energy are very important. While the use of fossil fuels can bring the much needed energy to these areas they come with a host of problems. Fossil fuel use contributes to greenhouse gas emissions, air pollution and ocean acidification. In many areas fossil fuels have to be transported in. The subsequent transmission and distribution can be difficult especially in rural areas. Dependence on fossil fuels also leaves the user vulnerable to disruption in deliveries and price fluctuations. While there are …

Interstitial Cell Seeding And Dynamic Conditioning Of Aortic Heart Valve Scaffolds, Allison Kennamer

All Theses

In 2011, U.S. Markets for Heart Valve Repair and Replacement Products estimated that roughly four million people in the United States are diagnosed with a heart valve disorder annually. And in the following year, the American Heart Association reported that approximately 35,000 deaths in the US were either directly or indirectly attributed to heart valve disease. Diseases of the heart valve are degenerative in nature and therefore progressively worsen unbeknownst to the patient until symptoms become clinically relevant. By this time, the valve is in such poor condition that complete replacement is often the only effective treatment. Current solutions are …

The Effects Of Different Size Gold Nanoparticles On Mechanical Properties Of Vascular Smooth Muscle Cells Under Mechanical Stretching, Tri Kieu

All Theses

The field of nanotechnology research has seen a large growth in the past few decades due to the great potential of novel nano-size material for useful applications such as drug delivery and medical imaging. Also, they are a promising platform for the detection of terrible diseases such as cancer and atherosclerosis. Although these materials hold great promise, there is very limited understanding about the biological effects of these nanoparticles on normal healthy cells, such as vascular smooth muscle cells (VSMCs). The VSMCs are unique cells due to the two distinct phenotype characteristics it can express: a contractile and a synthetic …

An Integrated Multidisciplinary Nanoscience Concentration Certificate Program For Stem Education, Karen S. Martirosyan, Mikhail M. Bouniaev, Malik Rakhmanov, Ahmed Touhami, Nazmul Islam, Davood Askari, Tarek Trad, Dmitri Litvinov, Sergey E. Lyshevski

Physics & Astronomy Faculty Publications

Integration of nanoscience and nanotechnology curricula into the College of Science, Mathematics, and Technology (CSMT) at the University of Texas at Brownsville (UTB) is reported. The rationale for the established multidisciplinary Nanoscience Concentration Certificate Program (NCCP) is to: (i) develop nanotechnology-relevant courses within a comprehensive Science, Engineering and Technology curriculum, and, to offer students an opportunity to graduate with a certificate in nanoscience and nanotechnology; (ii) to contribute to students' success in achieving student outcomes across all college's majors, and, improve the breath, depth and quality of science, technology, engineering and mathematics (STEM) graduates' education; (iii) through NCCP, recruit certificate- …

Dopaminergic Modulation Of Memory And Affective Processing In Parkinson Depression, Lee X. Blonder, John T. Slevin, Richard J. Kryscio, Catherine A. Martin, Anders H. Andersen, Charles D Smith, Frederick A. Schmitt

Magnetic Resonance Imaging and Spectroscopy Center Faculty Publications

Depression is common in Parkinson's disease and is associated with cognitive impairment. Dopaminergic medications are effective in treating the motor symptoms of Parkinson's disease; however, little is known regarding the effects of dopaminergic pharmacotherapy on cognitive function in depressed Parkinson patients. This study examines the neuropsychological effects of dopaminergic pharmacotherapy in Parkinsonian depression. We compared cognitive function in depressed and non-depressed Parkinson patients at two time-points: following overnight withdrawal and after the usual morning regimen of dopaminergic medications. A total of 28 non-demented, right-handed patients with mild to moderate idiopathic Parkinson's disease participated. Ten of these patients were depressed according …

Contrast Adaptation In The Lateral Eye Of Limulus Polyphemus, Tchoudomira Valtcheva

USF Tampa Graduate Theses and Dissertations

Luminance and contrast adaptation are neuronal mechanisms that the retina applies for continuous adjustment to light sensitivity though a collection of cellular and synaptic mechanisms distributed across the retinal network, thus accommodating the wide input range of the visual system within the constricted output range of retinal ganglion cells. Luminance mean adaptation has been demonstrated in the output neurons of the invertebrate eye (eccentric cells), and the aim of the study was to investigate whether the homology in visual processing extends to luminance variance (contrast) adaptation as well. The spike trains of individual eccentric cells were recorded from live horseshoe …

Skeletal Muscle Contraction Simulation: A Comparison In Modeling, Jonathan M. Ford

USF Tampa Graduate Theses and Dissertations

Computer generated three-dimensional (3-D) models are being used at increasing rates in the fields of entertainment, education, research, and engineering. One of the aspects of interest includes the behavior and function of the musculoskeletal system. One such tool used by engineers is the finite element method (FEM) to simulate the physics behind muscle mechanics. There are several ways to represent 3-D muscle geometry, namely a bulk, a central line of action and a spline model. The purpose of this study is to exmine how these three representations affect the overall outcome of muscle movement. This is examined in a series …

La Yeguada Volcanic Vomplex In The Republic Of Panama: An Assessment Of The Geologic Hazards Using 40ar/39ar Geochronology, Karinne L. Knutsen, William I. Rose, Brian Jicha

Department of Geological and Mining Engineering and Sciences Publications

La Yeguada volcanic complex is one of three Quaternary volcanic centers in Panama. To assess potential geologic hazards, new samples were analyzed using argon analysis (⁴⁰Ar/³⁹Ar), and obtained the following: the most recent eruption occurred approximately 32,000 years ago at the Media Luna cinder cone; the youngest dated eruption from the main dome complex occurred 357 ± 19 ka, producing the Castillo dome unit; Cerro Picacho, a separate dacite dome 1.5 km east of the main complex is 4.47 ± 0.23 Ma; and the El Satro Pyroclastic Flow unit surrounds the northern portion of the volcanic …

Spectral Analysis Of Nonstationary Heart Rate Of Neonates Receiving Therapeutic Hypothermia Treatment, Tareq Al-Shargabi

Theses and Dissertations

We studied Heart Rate Variability (HRV) evolution during therapeutic hypothermia in newborns with hypoxic ischemic encephalopathy (HIE) using spectral analysis. We hypothesized that HRV measures are predictive of neurological outcome in babies with HIE. Non-stationarity in the data causes inaccurate quantification of the spectral power. A modification was proposed to power spectral analysis approach to mitigate the effect of non-stationarity. The modified and the standard approaches were applied to cardiac beat-to-beat intervals of newborns receiving hypothermia treatment. The performance of the approaches in distinguishing the RRi dynamics of two groups of newborns was assessed using area under the receiver operating …

Design Of Engineered Biomaterial Architectures Through Natural Silk Proteins, Nicholas Kurland

Theses and Dissertations

Silk proteins have provided a source of unique and versatile building blocks in the fabrication of biomedical devices for addressing a range of applications. Critical to advancing this field is the ability to establish an understanding of these proteins in their native and engineered states as well as in developing scalable processing strategies, which can fully exploit or enhance the stability, structure, and functionality of the two constituent proteins, silk fibroin and sericin. The research outlined in this dissertation focuses on the evolution in architecture and capability of silks, to effectively position a functionally-diverse, renewable class of silk materials within …

Real-Time In Vivo Cherenkoscopy Imaging During External Beam Radiation Therapy, Rongxiao Zhang, David J. Gladstone, Lesley A. Jarvis, Rendall R. Strawbridge, P Jack Hoopes, Oscar D. Friedman, Adam K. Glaser, Brian W. Pogue

Dartmouth Scholarship

Cherenkov radiation is induced when charged particles travel through dielectric media (such as biological tissue) faster than the speed of light through that medium. Detection of this radiation or excited luminescence during megavoltage external beam radiotherapy (EBRT) can allow emergence of a new approach to superficial dose estimation, functional imaging, and quality assurance for radiation therapy dosimetry. In this letter, the first in vivo Cherenkov images of a real-time Cherenkoscopy during EBRT are presented. The imaging system consisted of a time-gated intensified charge coupled device (ICCD) coupled with a commercial lens. The ICCD was synchronized to the linear accelerator to …

Challenges And Opportunities For Multi-Functional Oxide Thin Films For Voltage Tunable Radio Frequency/Microwave Components, Guru Subramanyam, Melanie W. Cole, Nian X. Sun, Thottam S. Kalkur, Nick M. Sbrockey, Gary S. Tompa, Xiaomei Guo, Chonglin Chen, S. P. Alpay, G. A. Rossetti, Kaushik Dayal, Long-Qing Chen, Darrell Schlom

Electrical and Computer Engineering Faculty Publications

There has been significant progress on the fundamental science and technological applications of complex oxides and multiferroics. Among complex oxide thin films, barium strontium titanate (BST) has become the material of choice for room-temperature-based voltage-tunable dielectric thin films, due to its large dielectric tunability and low microwave loss at room temperature. BST thin film varactor technology based reconfigurable radio frequency (RF)/microwave components have been demonstrated with the potential to lower the size, weight, and power needs of a future generation of communication and radar systems. Low-power multiferroic devices have also been recently demonstrated. Strong magneto-electric coupling has also been demonstrated …

Oil Droplet Behavior At A Pore Entrance In The Presence Of Crossflow: Implications For Microfiltration Of Oil-Water Dispersions, Nikolai V. Priezjev, Tohid Darvishzadeh, Volodymyr V. Taravara

Mechanical and Materials Engineering Faculty Publications

The behavior of an oil droplet pinned at the entrance of a micropore and subject to clossflow-induced shear is investigated numerically by solving the Navier-Stokes equation. We found that in the absence of crossflow, the critical transmembrane pressure required to force the droplet into the pore is in excellent agreement with a theoretical prediction based on the Young-Laplace equation. With increasing shear rate, the critical pressure of permeation increases, and at sufficiently high shear rates the oil droplet breaks up into two segments. The results of numerical simulations indicate that droplet breakup at the pore entrance is facilitated at lower …

Novel Liposomes For Targeted Delivery Of Drugs And Plasmids, Marjan Javadi

Theses and Dissertations

People receiving chemotherapy not only suffer from side effects of therapeutics but also must buy expensive drugs. Targeted drug and gene delivery directed to specific tumor-cells is one way to reduce the side effect of drugs and use less amount of therapeutics. In this research, two novel liposomal nanocarriers were developed. This nanocarrier, called an eLiposome, is basically one or more emulsion droplets inside a liposome. Emulsion droplets are made of perfluorocarbons which usually have a high vapor pressure. Calcein (as a model drug) and Paclitaxel were used to demonstrate drug delivery, and plasmids and siRNA were used to exemplify …

The Santa Clara, 2013-11-14, Santa Clara University

The Santa Clara

No abstract provided.

Mech/Engr 371 Space Systems Design And Engineering: Introduction To Systems Engineering, Christopher Kitts

Robert "Bob" Twiggs STEM Education Collection

A  PowerPoint presentation created by Professor Christopher Kitts of Santa Clara University on "MECH/ENGR 371 Space Systems Design and Engineering: Introduction to Systems Engineering" on November 12, 2013.

Trajectory Generation And Optimization For Experimental Investigation Of Flapping Flight, Michael Schnebly Wilcox

Theses and Dissertations

Though still in relative infancy, the field of flapping flight has potential to have a far-reaching impact on human life. Nature presents a myriad of examples of successful uses of this locomotion. Human efforts in flapping flight have seen substantial improvement in recent times. Wing kinematics are a key aspect of this study. This study summarizes previous wing trajectory generators and presents a new trajectory generation method built upon previous methods. This includes a novel means of commanding unequal half-stroke durations subject to robotic trajectory continuity requirements. Additionally, previous optimization methods are improved upon. Experimental optimization is performed using the …

Biocompatibility Of Cao-Na2o-Sio2/Tio2 Glass Ceramic Scaffolds For Orthopaedic Applications, A. W. Wren, A. Coughlan, K. E. Smale, S. T. Misture, B. P. Mahon, O. M. Clarkin, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work aims to determine the effect of substituting TiO₂ for SiO₂ in a 0.62SiO₂-Na₂O-0.24CaO based glass-ceramic scaffold. High temperature X-ray Diffraction (HT-XRD) was used to determine the sintering temperature (700oC). Both optical microscopy and x-ray micotomography was used to determine the average pore size (540-680ìm) of each scaffold. Cytocompatibility of each scaffold was conducted using murine mesenchymal stem cells. © 2013 IEEE.

Gallium Containing Glass Polyalkenoate Bone Cements: Ion Release And E. Coli Inhibition, L. Placek, A. W. Wren, A. Coughlan, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Glass Polyalkenoate Cement (GPC) series (LCon., LGa-1 and LGa-2) containing gallium (Ga) and a 50 wt% addition of E11 polyacrylic acid (PAA), previously developed, was evaluated for ion release, specifically Si, Ca, Zn and Ga, and E. coli inhibition. The maximum inhibition was observed in the t = 0 samples and was 0.35 mm for LCon. and 0.65 mm for LGa-1 and LGa-2. © 2013 IEEE.

Comparison Of Emotion Evaluation Perception Using Human Voice Signals Of Robots And Humans, Vesna Kirandziska, Nevena Ackovska

UBT International Conference

Emotion perception is the process of perceiving other people’s emotions. It can be based on their facial expression, movement, voice and other biosignals people emit. The evaluation of human’s emotion is one characteristic of emotions. One of the research areas in Robotics is adapting humanistic behavior in robots. Today many robots are constructed. Some of them can even perceive emotions. In this paper a custom built emotion aware robot that perceives emotion evaluation is used to investigate the similarity and differences of the robot's and human's emotion perception. Voice signals from real human were recorded and the information for the …

Getting It Right The First Time: Robot Mission Guarantees In The Presence Of Uncertainty, Damian M. Lyons, Ronald C. Arkin, Paramesh Nirmal, Shu Jiang, Tsung-Ming Liu, J. Deeb

Faculty Publications

Certain robot missions need to perform predictably in a physical environment that may only be poorly characterized in advance. We have previously developed an approach to establishing performance guarantees for behaviorbased controllers in a process-algebra framework. We extend that work here to include random variables, and we show how our prior results can be used to generate a Dynamic Bayesian Network for the coupled system of program and environment model. Verification is reduced to a filtering problem for this network. Finally, we present validation results that demonstrate the effectiveness of the verification of a multiple waypoint robot mission using this …

Getting It Right The First Time: Robot Mission Guarantees In The Presence Of Uncertainty, Damian Lyons, Ron Arkin, Paramesh Nirmal, Shu Jiang, Tsung-Ming Liu, Julia Deeb

Faculty Publications

Abstract—Certain robot missions need to perform predictably in a physical environment that may only be poorly characterized in advance. We have previously developed an approach to establishing performance guarantees for behavior-based controllers in a process-algebra framework. We extend that work here to include random variables, and we show how our prior results can be used to generate a Dynamic Bayesian Network for the coupled system of program and environment model. Verification is reduced to a filtering problem for this network. Finally, we present validation results that demonstrate the effectiveness of the verification of a multiple waypoint robot mission using this …

Load Path Uncertainty In A Wood Structure And The Effect On Structural Reliability, Wenqi Wang, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

The roof truss bearing points of a light-framed wood house were instrumented with load cells. It was found that under dead load alone, symmetric and theoretically identical truss reactions have significant variation. A similar degree of reaction discrepancy was found under the application of uplift pressures caused by hurricane winds. Analysis revealed that the majority of this discrepancy is caused by inherent uncertainties in load path. Although uncertainties in load magnitude and material resistance are accounted for in design by use of appropriate load and resistance factors, load path is generally taken to be deterministic. In this study, load path …

Multi-Physical Study Of Mems Resonators And Oscillators, Xiaobo Guo

Electronic Theses and Dissertations

First, this research presents experimental and theoretical investigation of the response of micro scale dual-plate thermal-piezoresistive resonators (TPR) and self-sustained oscillators (TPO) to different gases and pressures. It is demonstrated that the resonant frequency of such devices follows particular trends in response to the changes in the surrounding gas and its pressure. A mathematical model has been derived to explain the damping dependent frequency shift characteristic of TPO. The solution of the model indicates that the stiffness of the actuator beam decreases as the value of damping coefficient drops at lower gas density caused by the change in the gas …