Medicine and Health Sciences Commons^™

Selective Targeting Of Microglia By Quantum Dots And Green Synthesis Of Metal Organic Biohybrids; Applications In Dynamic Cell And Assay Systems, Navya Uppu

Doctoral Dissertations

Neurological disorders are the leading cause of physical and cognitive disability across the globe, currently affecting approximately 15% of the worldwide population. Part of the glioma microenvironment are microglia, resident immune cells of the CNS that were thought to be involved in the pathogenesis of diverse neurodegenerative diseases. Though it remains uncertain what triggers microglial activation in these disorders, targeting and tracking microglial functions using nanotools like Quantum Dots (QDs) could help us elucidate them in such neurological diseases. This research focuses on the comparative study of different QDs formulations and their selective uptake by brain microglia in primary cultures …

Engineered Coating Of Natural Fibers And Oil-Water Interfaces With Self-Assembly Of Clay Nanotubes, Abhishek Panchal

Doctoral Dissertations

Taking into consideration two different types of surfaces, this dissertation proposes techniques to coat the surface of natural fibers and oil-water interfaces by spontaneous self-assembly of halloysite clay nanotubes. The material of choice, halloysite clay, is a widely available natural resource and can be used after minimal processing. In regards to chemical composition, halloysite clay resembles aluminosilicate mineral kaolin; physically, a defect in the crystal structure ordering causes the sheets of kaolinite to roll into halloysite nanotubes. The dimensions of halloysite nanotubes are dependent on the source, but generally vary from 200 nm to 3 µm in length, 100-150 nm …

The Effect Of Gamification On Audiology Awareness Among Young Adults, Shenque Lester

Doctoral Dissertations

The profession of audiology is projecting a critical shortage of practicing professionals in the near future. Although there are many potential factors that are contributing to this problem, it is generally agreed that audiology as a profession is not readily identified as a career choice by undergraduate students, nor a recognizable healthcare field/service among the general public. Due to the increased instances of hearing loss in the general population as well as the aging of the population and need for audiological services, it is imperative to find an efficient means to improve the awareness of audiology as a potential career …

Acoustical Properties Of Amplified And Unamplified Stethoscopes When Examining Typical Body Sounds, Jeni Abrams Dunnington

Doctoral Dissertations

A stethoscope is intended for three main diagnostic purposes: listening to heart sounds, listening to lung sounds, and determining the presence or absence of bowel sounds (Callahan, Waugh, Matthew, & Granger, 2007). Currently, on the market there are two types of stethoscopes for practitioners to choose: unamplified and amplified stethoscopes. Furthermore, there is little research on the sound pressure levels (SPLs) produced by stethoscopes on the market. Therefore, the current study seeks to measure the SPL produced by various popular unamplified stethoscopes and compare those findings to the SPLs produced by amplified stethoscopes. Secondly, the SPL of selected amplified stethoscopes …

The Effect Of Road Noise On Sound Pressure Levels And Preferred Listening Levels Using Personal Listening Devices, Hayley Himstedt

Doctoral Dissertations

Using a PLD in an automobile introduces unique threats such as volume levels set at higher levels to reduce the masking effects of road noise that enters the automobile. Passengers enjoying prolonged PLD exposure may be at an increased risk of noise exposure or fluctuating sound pressure levels resulting in hearing loss. Historically, hazardous noise has been primarily associated with industrial/occupational activities; however, harmful noise from recreational activities is also prevalent. The Center for Disease Control (2015) lists turning down PLD volume as one of their top three methods for reducing the possibility of NIHL in children. Excessive listening level …

Perceived Patient Control Over Personal Health Information In The Presence Of Context-Specific Concerns, Prabhashi A. Nanayakkara

Doctoral Dissertations

Information privacy issues have plagued the world of electronic media since its inception. This research focused mainly on factors that increase or decrease perceived patient control over personal health information (CTL) in the presence of context-specific concerns. Control agency theory was used for the paper's theoretical contributions. Personal and proxy control agencies acted as the independent variables, and context-specific concerns for information privacy (CFIP) were used as the moderator between proxy control agency, healthcare provider, and CTL. Demographic data and three control variables— the desire for information control, privacy experience, and trust propensity—were also included in the model to gauge …

Three-Dimensional Printing And Nanotechnology For Enhanced Implantable Materials, Karthik Kumar Tappa

Doctoral Dissertations

Orthopedic and oro-maxillofacial implants have revolutionized treatment of bone diseases and fractures. Currently available metallic implants have been in clinical use for more than 40 years and have proved medically efficacious. However, several drawbacks remain, such as excessive stiffness, accumulation of metal ions in surrounding tissue, growth restriction, required removal/revision surgery, inability to carry drugs, and susceptibility to infection. The need for additional revision surgery increases financial costs and prolongs recovery time for patients. These metallic implants are bulk manufactured and often do not meet patient's requirements. A surgeon must machine (cut, weld, trim or drill holes) them in order …

The Effect Of Cost, Benefit, And Level Of Technology On Patient Preference And Satisfaction With Hearing Aids, Lindsay M. Young

Doctoral Dissertations

The present double blind study sought to determine if experienced hearing aid users can differentiate between different levels of hearing aid technology. Specifically, the following research questions were addressed: (1) Are HINT scores affected by level of hearing aid technology for experienced hearing aid users?; 2) Is benefit/satisfaction of hearing aids affected by level of technology for experienced hearing aid users?; and (3) How do hearing aid users rank different levels of technology? If a perceptual difference in hearing aid technology is identified by hearing aid users, participants were asked to identify how money much they would be willing to …

Nanoformulation For Anticancer Drug Delivery: Enhanced Pharmacokinetics And Circulation, Gaurav Parekh

Doctoral Dissertations

In this study, we have explored the application of the Layer-by-Layer (LbL) assembly technique for improving injectable drug delivery systems of low soluble anticancer drugs (e.g. Camptothecin (CPT), Paclitaxel (PTX) or Doxorubicin (DOX)). For this study, a polyelectrolyte shell encapsulates different types of drug nanocores (e.g. soft core, nanomicelle or solid lipid nanocores).The low soluble drugs tend to crystallize and precipitate in an aqueous medium. This is the reason they cannot be injected and may have low concentrations and low circulation time in the blood. Even though these drugs when present in the cancer microenvironment have high anti-tumor inhibition, the …

The Relationship Between Sleep And Nutrition In Message Framing Among College Students, Abbey G. White

Doctoral Dissertations

The college years are often depicted as a time of immense change, specifically in relation to college students' level of nutrition and sleep quality. However, these health concerns not only impact college students' health but also their academic performance, mood, and as a result their future. The primary purpose of this study was to determine whether technologically enhanced health messages are more effective than the traditional text format for creating healthy behavioral changes amongst college students. Secondly, the study provides the opportunity to examine previous research involving message framing, specifically, regulatory focus theory and self-efficacy, in order to provide further …

Ear Specific Anl Measurements In Individuals With Unilateral And Asymmetrical Sensorineural Hearing Loss, Rebecca Howard

Doctoral Dissertations

The present study sought to determine if ANLs differ between ears within subjects with unilateral or asymmetrical SNHL. ANL was measured in four conditions (i.e., binaural, better ear, poorer ear unmasked, and poorer ear masked) in fifteen adults, nine with unilateral SNHL and six with bilateral asymmetrical SNHL. A significant difference between ANL in the four conditions (i.e., binaural, better ear, poorer ear unmasked, and poorer ear masked) was identified; however, the subjects with unilateral and asymmetrical SNHL behaved similarly throughout the testing. When comparing the four conditions, the results showed a significant difference between both the binaural ANL and …

Grant Proposal: Effects Of Sound Field Amplification On Standardized Test Scores, Jessica Ivey Coker

Doctoral Dissertations

Research has shown that the majority of classroom environments lack appropriate acoustical standards to ensure optimal learning conditions. During the early school grades, it is especially crucial that students overcome poor listening environments to obtain the fundamental educational skills necessary for academic success. Furthermore, the State of Louisiana conducts standardized test assessments (LEAP and iLEAP) to measure the students' knowledge and skills gained. These standardized test scores not only determine if the student progresses to the next grade, but also influences the amount of federal revenue and how the revenue is allocated to the schools. A proposed remedy to …

The Effect Of Auditory Processing Abilities On Acceptable Noise Levels, Brandee E. Richardson

Doctoral Dissertations

The purpose of the present study was to determine typical acceptable noise levels (ANLs) in children diagnosed with auditory processing disorder (APD) and compare those to ANLs in children without APD. Sixteen participants, eight children with APD and eight children without APD, were administered a complete audiological evaluation and a series of APD tests [Filtered Words, Competing Sentences, and Auditory Figure Ground (0) subtests of the SCAN– 3C; Staggered Spondaic Word test; and Pitch Pattern test] to determine normal or abnormal auditory processing ability. Conventional ANLs were measured on each participant to determine acceptance of background noise. The results …

Nanotechnology And Additive Manufacturing Platforms For Clinical Medicine: An Investigation Of 3d Printing Bioactive Constructs And Halloysite Nanotubes For Drug Delivery And Biomaterials, Jeffery A. Weisman

Doctoral Dissertations

Personalized medicine requires the development of new technologies for controlled or targeted drug delivery. Three-dimensional (3D) printing and additive manufacturing techniques can be used to generate customized constructs for bioactive compound delivery. Nanotechnology in the form of nanoparticles, used as a stand-alone construct or for material enhancements, can significantly improve established biomaterials such as PMMA based bone cements or enable new technology to have enhanced capabilities. Combinations of the technologies can be used in such applications as infectious disease treatments, chemotherapeutic targeted drug delivery or targeted delivery of nearly any bioactive compound.

Chemotherapeutic or antibiotic enhanced 3D printing filaments were …

Novel Rejection Methods And Fusion Approaches For Multi-Biometric Verification, Md Shafaeat Hossain

Doctoral Dissertations

This dissertation proposes methods and algorithms to improve the performance of biometric verification systems. It introduces a new rejection method, "symmetric rejection method," for multi-stage biometric verification. The symmetric rejection method significantly improves the performance over the state of the art rejection methods and controls the genuine reject rate which has not been specifically addressed in earlier studies. The dissertation also proposes a new fusion framework for multi-biometric verification systems, which achieves accuracy higher than parallel fusion framework, and provides convenience to genuine users. In addition, it proposes a framework consisting of impostor score based normalization, impostor score based rejection, …

The Effect Of Hearing Aid Program On The Perceived Sound Quality Of Music, Kalyn Kennedy Bradford

Doctoral Dissertations

Hearing loss affects many aspects of people's lives, including both communication and their ability to enjoy music. Currently, however, there is very little research on patient perception of music through hearing aids; therefore, the purpose of this study was to determine if there was a difference in the perceived listener satisfaction for music between a standard music program and the commonly used option for programming hearing aids (i.e., an automatic program). Data was collected using fifteen participants with symmetrical mild to moderately-severe sensorineural hearing loss with normal to near normal low frequency hearing. Participants were asked to listen to a …

Effect Of Noise On Transient-Evoked Otoacoustic Emissions And Pure-Tone Screening Audiometry, Laura Annette Wade

Doctoral Dissertations

Currently, the American Speech-Language Hearing Association (ASHA) recommends pure-tone audiometry as the preferred audiometric screening method of school-aged children; however, background noise is often present and can result in high referral rate. The current study's goal was to examine the effect of noise on the pass rate on transient-evoked otoacoustic emissions (TEOAEs) and pure-tone audiometric screening measures. Twenty normal hearing adults (M = 22.85), eighteen females and two males, were screened with TEOAEs and pure-tone audiometry in quiet and in different levels of noise (i.e., 40 dB SPL, 50 dB SPL, 60 dB SPL) in a sound-treated booth.

Pure-tone audiometry …

A Comparison Of The Effects Of Soundfield Amplification On Acoustical Characteristics And Word Recognition Performance In Relocatable And Permanent Classrooms, Sarah M. Babin

Doctoral Dissertations

There are three acoustical characteristics that should be addressed when developing a good classroom listening environment: signal-to-noise ratio (SNR), reverberation time (RT), and levels of background noise. Previous research has shown that soundfield (SF) amplification systems help to improve these three characteristics, thus improving the classroom listening environment. In the present study, two seventh-grade classrooms were used: one relocatable classroom and one permanent classroom. Acoustical characteristics and speech levels were measured in both classrooms under two amplification conditions (unamplified and amplified). Word recognition abilities of 37 students were also measured under the two amplification conditions in both classrooms. Results showed …

Receiver Position And Acceptance Of Noise, Speech Understanding, And Sound Quality Ratings, Anna L. Ford

Doctoral Dissertations

The effect of receiver position in a hearing aid on acceptance of background noise, speech intelligibility, sound quality judgments, and listener preference was measured in adults with normal to mild sloping to moderate to severe sensorineural hearing loss. Participants were fit with open-fit behind-the-ear (BTE) and receiver-in-the-ear (RITE) hearing aids. After a 3-week trial with each device, acceptance of noise levels, speech understanding in quiet and in noise, and sound quality ratings were conducted. At the conclusion of the study, listener preference between the devices was evaluated. Results revealed that receiver position did not significantly affect acceptance of background noise, …

Low Soluble Drug Encapsulation Based On Architecture Of Layer-By-Layer Assembly For Longer Circulation Time And Targeted Therapy, Pravin Pattekari

Doctoral Dissertations

A combined effect of sonication and layer-by-layer assembly (LbL) enhances the solubility of many poorly soluble inorganic and organic materials by forming stable particles with ca. 200 nm size and up to 90 wt% of loading. The entire method is reproducible, easy-to-handle, and flexible for varying surface properties according to the application of the materials. The method develops good colloidal stability of materials in buffers and maintains architecture for future improvement. A top-down approach, with a combined effect of sonication and LbL assembly, ruptures the material and allows adsorption of oppositely charged polyelectrolytes simultaneously. Thus, the approach is applicable for …

The Measurement Of Auditory Interhemispheric Transfer Time (Ihtt) In Children With Normal Auditory Processing Abilities, Brittany Suzanne Keahey

Doctoral Dissertations

Interhemispheric transfer time (IHTT) is the time it takes for information to be transmitted from one hemisphere to the other. The goal of this study was to determine if differences existed in the IHTT of children 6 to 9 years of age with normal auditory processing abilities by the use of an objective measure (auditory late evoked potentials [ALEPs]), specifically waves P1, N1 and P2. It was hypothesized that there would be no difference in IHTT between the groups due to the age range of participants being tested. The 16 participants were divided into two groups based on age and …

Effects Of Untrained Earmold Impression Taking On Custom Hearing Protector Device Performance, Kelly R. Pack

Doctoral Dissertations

Today's consumer is increasingly turning to the internet for both healthcare information as well as the purchase of custom hearing protection devices (HPDs). These HPDs are often cast from do-it-yourself home ear impression kits that include a syringe and silicone earmold impression material to be injected into the ear canal. Although not required by law, earmold impressions have typically been taken by medical professionals and other individuals formally trained in the procedures and safety measures of effective earmold impression taking. The main purpose of this study was to determine if do-it-yourself earmold impressions produce HPD's with lower attenuation levels than …

The Effect Of Network Transitions On Spontaneous Activity And Sycnhrony In Devloping Neural Networks, Jude P. J. Savarraj

Doctoral Dissertations

Connectivity patterns of developing neural circuits and the effects of its dynamics on network behavior, particularly the emergence of spontaneous activity and synchrony, are not clear. We attempt to quantify anatomical connectivity patterns of rat cortical cultures during different stages of development. By culturing the networks on dishes embedded with micro electrode arrays, we simultaneously record electrical activity from multiple regions of the developing network and monitor its electrical behavior, particularly its tendency to fire spontaneously and to synchronize under certain conditions. We investigate possible correlations between changes in the network connectivity patterns and spontaneous electrical activity and synchrony. Cocultures …

Asymmetrical Speech In Noise Assessment For Children With (Central) Auditory Processing Disorders, Jessica Vaughn

Doctoral Dissertations

The primary purpose of this investigation was to determine if children with (Central) Auditory Processing Disorder have better word recognition abilities for monosyllabic words under monaural speech-in-noise conditions than binaural speech-in-noise conditions. Fifteen participants, five females and ten males, ages 8-10 years, were included in this study. There were 7 children placed in the experimental group with a diagnosis of (C) APD identified from the Louisiana Tech University Speech and Hearing Center. There were 8 typically developing children placed in the control group. Each participant had pure-tone thresholds of 0-20 dB HL for 250-8000 Hz bilaterally. The SCAN-3 for children, …

Ultrasonication Assisted Layer-By-Layer Technology For The Preparation Of Multi-Functional Anticancer Drugs Paclitaxel And Lapatinib, Xingcai Zhang

Doctoral Dissertations

In this dissertation, ultrasonication assisted Layer-by-Layer (LbL) technology for the preparation of multifunctional poorly water-soluble anticancer drug nanoparticles, paclitaxel and lapatinib, has been developed. Many FDA approved drugs are very low soluble in water; therefore, it is very difficult to load and control their release and targeting efficiently, which greatly confines their application. The development of this method will pave the way for the development and application of those low soluble anticancer drugs.

In the first part of this dissertation, the first approach for powerful ultrasonication, the top-down approach (sonicating bulk drug crystals in polyelectrolyte solution), was successfully applied for …

Real-Time Analysis Of Brain Tumor Cell Dynamics: Novel Thermoelectric Detection Of L-Glutamate And Cell Metabolism Using Microfluidics, Siva Mahesh Tangutooru

Doctoral Dissertations

This study describes the design, fabrication and applications of a novel thermoelectric microfluidic bio-sensor. The bio-sensor is used for real time detection of the L-glutamate (L-glu) dynamics and metabolism for brain tumor cells immobilized in a microfluidic device. The microfluidic device is fabricated using a polymer/glass laminating technique (Xurography). An antimony-bismuth thin-film thermopile (primary sensing element) is integrated to the microfluidic device. The brain tumor cells are immobilized over the thermopile covering measuring and reference junctions of the thermopile using a poly-l-lysine coating layer. L-glutamate oxidase (L-GLOD) is immobilized over the measuring junctions of the thermopile prior to the immobilization …

Effects Of Gender Composition Of Target And Sender Dyads On The Tendency To Infer Lies, Byron J. Simoneaux

Doctoral Dissertations

Lying is so common in human behavior that some have labeled it a social skill. Despite the ubiquity of lies, humans have consistently been found to be poor lie detectors. Attempts have been made to improve the accuracy of human lie detection. Unfortunately, the most successful training only improves accuracy slightly above the level of chance. Because of its importance to society, considerable effort has been aimed at developing methods to help determine when people are lying. Researching how and why humans infer that another person is lying has the potential to advance the understanding of lie detection. Researchers have …

Development Of An Elementary School Background Noise, Amanda L. Mccann

Doctoral Dissertations

The deleterious effects of noise on hearing, comprehension, and academic development have been widely studied. In an effort to accurately observe the effects of noise on specific listening environments, researchers have relied on commercially available forms of background noise. However, these commercially available recordings only contain adult speech and background noises associated with adult environments. A commercially available form of background noise that represents the sounds associated with elementary and middle schools are not readily available. Given that much effort has gone into examining the effects of background noise on classroom performance, it would appear prudent that a background noise …

Asymmetric Directional Microphone Fittings For Individuals With An Asymmetric Hearing Loss, Jessica White

Doctoral Dissertations

The present study investigated the effects of asymmetric directional microphone fittings on participants' acceptance of background noise and speech understanding in noise abilities. Thirteen adult, bilateral hearing aid users or non-hearing aid users with bilateral asymmetrical sensorineural hearing loss were fit binaurally with four different microphone conditions (i.e., bilateral omnidirectional, asymmetric directional poorer ear, asymmetric directional better ear, and bilateral directional) and monaurally with two microphone conditions (i.e., unilateral directional better ear and unilateral omnidirectional better ear). The amplification used was a pair of Siemens Intuis directional behind-the-ear hearing aids and comply earmolds.

The results indicated speech understanding in noise …

Bluetooth Headset Specifications And Its Possible Effects On Hearing Loss, Kristi Ann Anderson

Doctoral Dissertations

The purpose of this study was to determine Bluetooth headset specifications and its potential effects on hearing loss. The following research questions were assessed: (1) what is the maximum peak output of various Bluetooth headsets coupled to a cellular phone; (2) what is the average output of various Bluetooth headsets coupled to a cellular phone; and (3) what is the frequency response of various Bluetooth headsets coupled to a cellular phone? Sixteen Bluetooth headset devices of various manufacturers were used for this study. Bluetooth headsets used for this study were determined by consumer demands and lack of output specifications provided …