Engineering Commons^™

Measurement Of White Matter Structure Changes In Amyotrophic Lateral Sclerosis Using Fractal Analysis, Zao Liu

ETD Archive

Amyotrophic lateral sclerosis (ALS) is recognized as a motor neuron disorder affecting the structure and function of the brain and neuromuscular system. Very little is known, however, that the nervous system degeneration is dependent on disease phenotypes of ALS. The purpose of this study was to determine the degree of brain white matter (WM) structure degeneration in four ALS patient groups characterized by their clinical signs and neuroimaging measurements. Fractal dimension (FD) of three-dimensional (3D) brain WM images was quantitatively analyzed to evaluate the WM structural complexity, including complexity levels of the WM skeleton, surface and general structures in ALS …

An Assessment Of The Accuracy Of Magnetic Resonance Phase Velocity Mapping In Turbulent Flow Through Orifices, Sahitya Pidaparthi

ETD Archive

Magnetic resonance phase velocity mapping (MRPVM) is an established clinical technique to measure blood flow. The acquired information can be used to diagnose a variety of cardiovascular disease. One of the main limitations of MRPVM is that it cannot quantify the flow under turbulent flow conditions. Such conditions develop in certain cases such as in heart valve stenosis and arterial stenosis. Specifically, heart valve stenosis is a serious disease in which the valve does not open as much as necessary for blood to pass through. As a result, the heart has to overwork to overcome the increased resistance. If untreated, …

Reinforced Chitosan-Based Heart Valve Scaffold And Utility Of Bone Marrow-Derived Mesenchymal Stem Cells For Cardiovascular Tissue Engineering, Mohammad Z. Albanna

Wayne State University Dissertations

Recent research has demonstrated a strong correlation between the differentiation profile of mesenchymal stem cells (MSCs) and scaffold stiffness. Chitosan is being widely studied for tissue engineering applications due to its biocompatibility and biodegradability. However, its use in load-bearing applications is limited due to moderate to low mechanical properties. In this study, we investigated the effectiveness of a fiber reinforcement method for enhancing the mechanical properties of chitosan scaffolds. Chitosan fibers were fabricated using a solution extrusion and neutralization method and incorporated into porous chitosan scaffolds. The effects of different fiber/scaffold mass ratios, fiber mechanical properties and fiber lengths on …

An Investigation Of The Biomechanical Response From Shock Wave Loading To The Head, Alessandra Dal Cengio Leonardi

Wayne State University Dissertations

There is a pressing need for a comprehensive explanation of the mechanism of brain injury after exposure to blast and several hypotheses have been suggested. The focus of this research was to investigate one of the hypotheses for primary brain injury due to blast: multimodal skull flexure. The significance of this research is twofold. First, resolution of the mode of energy transfer and of the induced stresses within the skull-brain system will allow for creations of mitigation/protective techniques/equipment, as well as design of experiments investigating live-cell response using more reliable physical models. Second, the data obtained experimentally will be available …

Finite Element Reconstruction Of Real World Aortic Injury In Near-Side Lateral Automotive Crashes With Conceptual Countermeasures, Aditya Neelakanta Belwadi

Wayne State University Dissertations

Traumatic rupture of the aorta (TRA) remains the second most common cause of death associated with motor vehicle crashes after brain injury. On an average, nearly 8,000 people die annually in the United States due to blunt injury to the aorta. It is observed that more than 80% of occupants who suffer an aortic injury die at the scene due to exsanguination into the chest. With the advent of more accurate and established human body finite element (FE) models, FE crash reconstruction methods may become a valuable tool when assessing crash scenarios and occupant injury mechanisms.

The current study is …

Differences Between Adult And Pediatric Neck Muscle Stress Due Muscle Recruitment Patterns, Renee Dawson

Wayne State University Dissertations

In 2000 and 2001 an estimated 150,000 children between the ages of 0 and 8 years old were injured or killed in a motor vehicle accident. Despite advances in child safety restraints and vehicle restraints, automobile accidents remain the primary cause of death for children in the 0-8 year old age group. In 1982, in an attempt to reduce the number of deaths and injuries of children, the first child crash test dummy was developed. The responses of this dummy were scaled from the adult response data based on the assumption that children were similar to adults both anatomically and …

Micromotion And Scarring Do Not Contribute To Failure Of Regenerative Peripheral Neural Interfacing, Nivedita Khobragade

Bioengineering Theses - Archive

Neuroprosthetics facilitate amputees with motor function restoration by interfacing nervous system with artificial limb and enabling control of the prosthetic device by volitional thought. Though such neurointerfacing provides dexterity nearly mimicking natural limb agility, the clinical viability of such prosthetics is limited by the lack of long-term reliability. In central nervous system, these implants fail due to foreign body reaction and glial scar formation around the implant. The cause of decrease in active sites of interfacing in peripheral nervous system, which is less invasive than central nervous system implantation, has not been established. Recently an open architecture, regenerative peripheral neural …

Methodology Of Citrate-Based Biomaterial Development And Application, M. Richard Tran

Bioengineering Dissertations - Archive

Biomaterials play central roles in modern strategies of regenerative medicine and tissue engineering. Attempts to find tissue-engineered solutions to cure various injuries or diseases have led to an enormous increase in the number of polymeric biomaterials over the past decade. The breadth of new materials arises from the multiplicity of anatomical locations, cell types, and mode of application, which all place application-specific requirements on the biomaterial. Unfortunately, many of the currently available biodegradable polymers are limited in their versatility to meet the wide range of requirements for tissue engineering. Therefore, a methodology of biomaterial development, which is able to address …

Investigation Of Neural Correlates Between Perception Of Pain And Hemodynamic Response Measured In The Pre-Frontal Cortex Using Functional Near Infra-Red Spectroscopy, Venkatagiri Krishnamurthy

Bioengineering Dissertations - Archive

Perception of pain is multi-dimensional, comprising three major psychological dimensions: sensory-discriminative, motivational-affective and cognitive-evaluative. This dissertation study investigates the cognitive evaluation of pain, by acquiring functional Near Infra-Red Spectroscopic (fNIRS) measurements from the prefrontal cortex (PFC) areas, during mechanical and thermal pain stimulation induced on the subject's volar forearm. Clustered-wise analysis on the oxy-hemoglobin (HbO) response from specific PFC areas was followed by categorizing the resulting HbO response into early (0.1-12sec) and late (12.1-25sec) phases. For each respective phase, regression analysis was carried between the HbO-derived parameters and behaviorally measured pain rating. The major findings of this study include: (1) …

Novel Applications Of Compressed Sensing To Magnetic Resonance Imaging And Spectroscopy, Sairam Geethanath

Bioengineering Dissertations - Archive

In this work, three novel applications of compressed sensing to MRI have been developed and implemented which accomplish reduction in acquisition time, thereby also enabling increased spatial and/or temporal resolution. The first application is for reducing the acquisition time of conventional 1H magnetic resonance spectroscopic imaging (MRSI), which requires alongeracquisition time than conventional MRI. The implementation involved exploiting the inherent sparsity of the MRSI data in the wavelet domain by the use of Daubechies wavelet. This was demonstrated on an in vitro phantom, 6 healthy human brain MRSI data sets, 2 brain and prostate cancer data sets. The reconstructions were …

Novel ¹H Mr Probes To Interrogate The Tumor Microenvironment, Praveen Kumar Gulaka

Bioengineering Dissertations - Archive

The term "tumor microenvironment" usually refers to the description of the physiological and metabolic conditions within solid tumors (primary or metastatic), and is significantly different from that of normal tissues. Assessment of factors like pH, tissue oxygen tension (pO2) and gene expression in the tumor microenvironment and the ability to image them in vivo can provide useful prognostic information. For example, hypoxia (low pO2), typically distributed heterogeneously in solid tumors, is known to affect both radiation sensitivity and the development of metastases thereby influencing the response to treatment. This dissertation research focuses on the evaluation of novel probes to interrogate …

Wireless Closed-Loop Feedback Systems For Automatic Detection And Suppression Of Nociceptive Signals, Aydin Farajidavar

Bioengineering Dissertations - Archive

Chronic pain is an important public health issue. Several approaches have been implemented for management of chronic pain, including surgical implantation of neurostimulators. Neurostimulators have been used in clinics for spinal cord implantation and they have been suitable for relieving certain types of pains, such as neuropathic pain in leg or arm, complex regional pain, and refractory angina. The stimulation at spinal cord has little relieving effects on syndromes such as facial pain, cluster headache, phantom limb pain, and post stroke pain. For treating such syndromes, electrical stimulation of deep brain structures such as thalamic nuclei (e.g. ventroposterolateral (VPL) or …

Cell Specific Guidance Of Nerve And Vascular Regeneration Through Sustained Growth Factor Release, Parisa Lotfi

Bioengineering Dissertations - Archive

Regenerative peripheral nerve interfaces have been proposed as viable alternatives for the natural control of robotic prosthetic devices. However, sensory and motor axons at the neural interface are of mixed submodality types, which difficult the specific recording from motor axons and the eliciting of precise sensory modalities through selective stimulation. Here we evaluated the possibility of using type-specific neurotrophins to preferentially entice the regeneration of defined axonal populations from injured peripheral nerves. Segregation of mixed sensory fibers from dorsal root ganglion neurons was evaluated in vivo by compartmentalized diffusion delivery of nerve growth factor (NGF) and neurotrophin-3 (NT-3), to preferentially …

Photosynthetically Active Protoplasts For Power Scavenging, Absorbance And Optical Density Analysis, Ahmed Shahid

Bioengineering Theses - Archive

Plants and photosynthetic bacteria hold protein molecular complexes that can efficiently harvest photons. This paper presents fundamental studies to harness photochemical activities by converting photonic energy into electrical energy. The electrical behavior of protoplast extracted from Arabidopsis plants was characterized in the presence and absence of light. The photo-induced reactions of photosynthesis were measured using a patch clamp measurement system at a constant voltage. This research also reports the absorbance and optical density measurements showing very large bandwidth for extracted protoplasts. The optical measurements were performed on the protoplast Arabidopsis and showed absorption bands at a number of wavelengths. The …

An Investigation Of Support Vector Machine Classifier In Detecting Nocturnal Airway Obstruction From Spontaneous Heart Rate Combined With Ecg Morphology Changes, Harshan Ravi

Bioengineering Theses - Archive

Sleep apnea is a sleep disordered breathing resulting from limitation or cessation to breathing for 10 or more seconds. The prevalence of sleep apnea has increased exponentially in the past decade. The increase in epidemic in sleep apnea is associated with increase in the cases of obesity. It is estimated that 12-18 million of American adults suffer from sleep apnea, which is a sizable sector of the adult population. Sleep apnea is risk factor for hypertension, type II diabetes, and congestive heart failure. Sleep apnea may go undiagnosed for a long period of time after its onset due to complexity …

Design, Fabrication, And Testing Of An Electrospinning Apparatus For The Deposition Of Pmma Polymer For Biomedical Applications, Harsha Malshe

Inquiry: The University of Arkansas Undergraduate Research Journal

This paper describes the successful design and fabrication of a deposition system for synthesis and assembly of nanoscale and submicron sized fibers of poly(methylmethacrylate)(PMMA) polymer. To optimize the electrospinning deposition process, the distance between the needle and the electrically grounded substrate, the applied voltage, and the concentration of PMMA polymer in the solution were varied. PMMA fibers as small as 500 nanometers were observed using scanning electron microscopy (SEM). The chemical signature of PMMA was confirmed for best quality and retention of chemistry using Fourier Transformed Infrared spectroscopy (FT-IR). PMMA is a biocompatible polymer, and nanofibers of PMMA are key …

A Secure Behavior Modification Sensor System For Physical Activity Improvement, Alan Price

CGU Theses & Dissertations

Today, advances in wireless sensor networks are making it possible to capture large amounts of information about a person and their interaction within their home environment. However, what is missing is how to ensure the security of the collected data and its use to alter human behavior for positive benefit.

In this research, exploration was conducted involving the "infrastructure" and "intelligence" aspects of a wireless sensor network through a Behavior Modification Sensor System. First was to understand how a secure wireless sensor network could be established through the symmetric distribution of keys (the securing of the infrastructure), and it involves …

The Role Of Conflict Management On Virtual Team Performance And Satisfaction, Pilar Pazos, Anil Ustun, Rolando Delaguila

Engineering Management & Systems Engineering Faculty Publications

The role that input factors from project planning processes play on conflict emergence and conflict resolution in virtual teams is not well understood. Of particular interest for this paper is the role that factors during planning stages play in preventing interpersonal conflict, supporting conflict resolution and ultimately enhancing team outcomes in virtual team settings. This study examines the relationships among commitment to team goals, conflict management and team outcomes in virtual teams. First we provide an in depth review of relevant empirical findings. Next, we describe a study examining the relationships between three sets of variables: 1) goal commitment, 2) …

Comparison Of Progression Of Diffuse Axonal Injury With Histology And Diffusion Tensor Imaging, Nisrine Zakaria

Wayne State University Dissertations

Diffuse axonal injury, also known as traumatic axonal injury (TAI), is a major contributor to the pathology of traumatic brain injury. However, TAI is undetectable to conventional clinical magnetic resonance (MR) imaging techniques. Histologically, TAI is characterized by swollen axons that eventually disconnect and form axonal retraction balls (RB) in various white matter tracts. MR-diffusion tensor imaging (MR-DTI) has been reported to be sensitive to TAI in human TBI patients by measuring water molecular diffusion motion in white matter fiber tracts. To date, only one correlative animal study has been carried out to investigate the DTI relationship to TAI, and …

Characterization Of Multifunctional Biodegradable - Biocompatible Icg-Loaded Nanoparticles And Their Feasibility For Prostate Cancer Imaging And Phototherapy, Ronak Patel

Bioengineering Theses - Archive

Prostate cancer is the most common male cancer in the United States, and the second leading cause of cancer death in men. The conventional diagnostic procedures use an invasive approach to collect the biopsy tissue samples. Also, treatments currently used include radiotherapy, chemotherapy and surgical removal of the prostate associated with high risks of surgical complications. Among all the imaging modalities, Near Infrared (NIR) optical imaging could be a possible candidate for minimally invasive diagnosis of prostate cancer with avoidance of harmful radiation and relatively low cost. This motivation brings the development of multifunctional polymeric (di- lactide-co-glycolic acid) (PLGA) Nanoparticles …

Organic Biocompatible Nanolayered Polymerization Of Solid-State Devices, Sri Divya Vidyala

Bioengineering Theses - Archive

Nanotechnology plays a major role in today's society due to its convergence of nanoscale which is the level of atoms and molecules as a part of miniaturization trend. The interference between biomedical and nanotechnology are of intense research. It concerns about the utilization of miniature biological systems such as nucleic acids, proteins, cells and cellular components to fabricate functional organic and inorganic nanostructures. This research work focuses on the process of developing a simple method to obtain fluorinated organic nanocoating which can be used to coat 3D structures and also explain the extended applications of the coating in the fields …

Substrate Stiffness Adjustable Pdms Device/Array For Understanding Its Effect On Cell Growth, Differentiation And Migration, Chetan Bhuwania

Bioengineering Theses - Archive

The mechanical properties of the cellular environment play an important role in the functioning of the cell. Cells attach to the extracellular matrix or other surrounding cells, thus sensing their mechanical properties and tune their own internal mechanical properties accordingly. A number of in vitro studies have been performed to study various cellular mechanical phenomena, but most of them employ a very stiff substrate such as glass or plastic that does not encompass the physiologically relevant range. Also, for tissues of the nervous system, the relationship between the substrate stiffness and the cellular behavior is less understood. In this study, …

Diagnosis Of Breast Cancer Using Auto-Flourescence Lifetime And Light Reflectance Spectroscopy: A Potential Tool For Positive Margin Assessment, Shivaranjani Shivalingaiah

Bioengineering Theses - Archive

Malignant Breast Neoplasm (MBN) or breast cancer is a heterogeneous cancer type originating in the breast tissue. Surgery is considered the primary treatment for breast cancer, with many early stage patients being cured without recurrence. The goals of the surgery include complete resection of the primary tumor, with negative margins to reduce the risk of local recurrences. Further, pathological staging of the tumor and axillary lymph nodes are carried out to extract necessary prognostic information. Surgery works well in case of complete Mastectomies. However, the biggest challenge for this technique is determining adequate margins on the partial mastectomy (lumpectomy) specimen. …

A Viscoelastic Model For Human Prolapsed Vaginal Wall Tissue, Milton Ma

Bioengineering Theses - Archive

Pelvic organ prolapse (POP) affects thousands of elderly women each year. Improvements in surgical repair could benefit from the understanding of the biomechanical properties of the vaginal wall (VW) tissues to better tailor the needed repair. VW tissue property has been measured by uniaxial tensile test on excised fresh human anterior VW tissues. Data available, however, are limited to elastic modulus obtained in vitro. Recently, in vivo biomechanical data of VW from POP patients have been obtained by adapting a cutometer-like device, the BTC-2000TM (SRLI). The Voigt and Standard Linear models in conjunction with the framework of quasi-linear viscoelasticity theory …

3-Dimensional Scanning And Reconstruction Using A Modified Hrt-Rcm Corneal Confocal Microscope, Saurabh Vaidya

Bioengineering Theses - Archive

The HRT II - Rostock Corneal Module (HRT II-RCM) provides excellent resolution, contrast and optical sectioning capability for cornea imaging. It offers the most detailed views of cornea structure and pathology. However, the major limitation of this microscope is its scanning method. It has a threaded dial on the front side of the microscope which is coupled to the objective, and this dial has to be rotated manually to change the focal plane and to scan through the cornea.The dial is within inches of the cornea. During the scans, manual control causes serious interference and degrades the quality of the …

Optimization Of Hydrogel System For Complex Wound Healing, Nikhil Vilas Aphale

Bioengineering Theses - Archive

Various conventional therapies and preventive measures have been developed and used for treating complex wounds; however, patients with complex wounds still develop wound infection and consist of delayed wound healing. These limitations necessitate the development of a novel therapeutic system, which is cost effective, easily apply onto the complex wounds, and consists of an efficient therapeutic nature. An in situ forming hydrogel system, made up of a novel biodegradable elastomer poly (ethylene glycol) maleate citrate (PEGMC), was designed and optimized for complex wound healing. Biocompatibility of this hydrogel system was studied by determining the toxicity of both the formation factors, …

Development, Validation, And Application Of A Noninvasive Spinal Motion Measurement System, Shaun Kevin Stinton

University of Kentucky Doctoral Dissertations

Spontaneous vertebral fractures are a large and growing health care problem. Biomechanical factors, specifically, abnormal posture or gait‐related spinal motion may interact with age‐weakened bone to induce altered spinal biomechanics that in turn increase the likelihood of vertebral body fracture. This research takes steps towards the goal of reducing the number of vertebral fractures in two phases: 1) Validation of a noninvasive spinal motion measurement system in cadaver torsos and 2) Application of the measurement system in human subjects.

The cadaver study compared vertebral motion at 4 levels (T7,T12,L3,L5) as measured by adhesive skin markers versus motion measured by bone …

Development Of A Biomechanical Surrogate For The Evaluation Of Commotio Cordis Protection, Nathan Dau

Wayne State University Dissertations

Commotio Cordis (CC) has proven to be life threatening for young athletes as it is the second leading cause of mortality in youth sports. In the past 15 years, researchers have been working to understand the pathophysiology of this event. It has been proven that impacts directly over the cardiac silhouette during a vulnerable period of the cardiac cycle can cause CC. In order to reduce the occurrence of CC in sports, chest protectors need to be tested for efficacy. Currently there is no biofidelic surrogate to serve this purpose. In order to test equipment to a given standard of …

Ethanol Yields And Cell Wall Properties In Divergently Bred Switchgrass Genotypes, Gautam Sarath, Bruce S. Dien, Aaron J. Saathoff, Kenneth P. Vogel, Robert B. Mitchell, Han Chen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Genetic modification of herbaceous plant cell walls to increase biofuels yields is a primary bioenergy research goal. Using two switchgrass populations developed by divergent breeding for ruminant digestibility, the contributions of several wall-related factors to ethanol yields was evaluated. Field grown low lignin plants significantly out yielded high lignin plants for conversion to ethanol by 39.1% and extraction of xylans by 12%. However, across all plants analyzed, greater than 50% of the variation in ethanol yields was attributable to changes in tissue and cell wall architecture, and responses of stem biomass to diluteacid pretreatment. Although lignin levels were lower in …

Magnetic Resonance Image Processing Using Levy, Jonathan Blackledge, Matthew D. Blackledge

Conference papers

We consider the physical nature of the self-diffusion of water molecules in tissue and explore how (Nuclear) Magnetic Resonance (MR) imaging may be used as a means of measuring the rate of diffusion in vivo. A discussion is presented on how these techniques may be implemented as a non-invasive means of assessing the response of tumours to novel therapeutics including some of the basic advantages and disadvan- tages when compared to other methods. The physical basis and mathematical models for diffusion are considered together with models for the distribution of the diffusion co- efficient including a Lévy distributed model. Using …