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Hatching Asynchrony Occurs As A Byproduct Of Maintaining Egg Viability, Robert Aldredge Jan 2008

Hatching Asynchrony Occurs As A Byproduct Of Maintaining Egg Viability, Robert Aldredge

Electronic Theses and Dissertations

For many organisms, embryonic development begins directly after an egg (ovum) has been fertilized by sperm; however, some organisms delay the onset of embryonic development until conditions are favorable for raising young. This delayed onset of development could occur by delaying implantation of fertilized ovum on the uterine wall, as seen in many mammals. Birds delay embryonic development by laying a set of fertilized ova over a period of consecutive days. These fertilized ova are protected from the ambient environment by an exterior shell, and it is in this shell outside of the female s body that embryonic development occurs, …

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The Distribution, Abundance, And Habitat Use Of The Big Cypress Fox Squirrel, (Sciurus Niger Avicennia)., Danielle Munim Jan 2008

The Distribution, Abundance, And Habitat Use Of The Big Cypress Fox Squirrel, (Sciurus Niger Avicennia)., Danielle Munim

Electronic Theses and Dissertations

Human population growth and development reduce the area and quality of natural communities and lead to a reduction of populations of the species associated with them. Certain species can be useful indicators or "focal species" for determining the quality of ecosystem remnants and the required management practices. Tree squirrels are good models for studies on the effects of fragmentation because they depend on mature forests. The Big Cypress fox squirrel, (Sciurus niger avicennia), a state-listed Threatened subspecies endemic to south Florida, appears sensitive to habitat fragmentation and fire regime. This research aims to assess the conservation status of the Big …

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Determination Of The Degradation Mechanism For Polychlorinated Biphenyl Congeners Using Mechanically Alloyed Magnesium/Palladium, Robert Devor Jan 2008

Determination Of The Degradation Mechanism For Polychlorinated Biphenyl Congeners Using Mechanically Alloyed Magnesium/Palladium, Robert Devor

Electronic Theses and Dissertations

Polychlorinated biphenyls are a ubiquitous environmental contaminant that can be found today throughout the world in soils and sediments, lakes and rivers, and flora and fauna. PCBs have percolated throughout the food chain, so that almost every human being has a detectable amount of the contaminant within their blood stream. Existing remediation methods include incineration, dredging and landfilling, and microbial degradation, but all of these methods have drawbacks that limit their effectiveness as treatment options. Recently, the use of zero-valent metals as a means of reductive dechlorination has been explored. Using a combination of zero-valent magnesium and catalytic palladium, a …

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Surface Engineering Of Gold Nanoparticles And Their Applications, Qiu Dai Jan 2008

Surface Engineering Of Gold Nanoparticles And Their Applications, Qiu Dai

Electronic Theses and Dissertations

Gold nanoparticles (AuNPs) with their unique sizes, shapes, and properties have generated much enthusiasm over the last two decades, and have been explored for many potential applications. The successful application of AuNPs depends critically on the ability to modify and functionalize their surface to provide stability, compatibility, and special chemical functionality. This dissertation is aimed at exploring the chemical synthesis and surface modification of AuNPs with the effort to (1) control the number of functional groups on the particle surface, and to (2) increase the colloidal stability at the physiological conditions. To control the functionality on the particle surface, a …

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Attachment Style's Impact On The Perception Of Self-Verifying And Self-Enhancing Comforting Messages, Krista Shellabarger Jan 2008

Attachment Style's Impact On The Perception Of Self-Verifying And Self-Enhancing Comforting Messages, Krista Shellabarger

Electronic Theses and Dissertations

This study investigates the connection between one's adult attachment style and one's evaluation of verifying or enhancing comforting messages. Drawing from research by Swann (2005) and Katz and Joiner (2002), the hypothesis predicted that an individual would prefer verifying messages over enhancing messages regardless of attachment style. A research question was also posed: Will an individual's adult attachment style moderate the degree to which a person perceives the communication of verifying or enhancing messages as helpful or effective? In an effort to find these answers, a questionnaire was completed by 251 individuals. Results indicate a preference for verifying messages among …

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Using Stable Isotopes To Assess Population Structure And Feeding Ecology Of North Pacific Humpback Whales (Megaptera Novaeangliae), Briana Witteveen Jan 2008

Using Stable Isotopes To Assess Population Structure And Feeding Ecology Of North Pacific Humpback Whales (Megaptera Novaeangliae), Briana Witteveen

Electronic Theses and Dissertations

The North Pacific humpback whale (Megaptera novaeangliae) is a wide-ranging baleen whale species with a complex life history and population structure. As seasonal migrants, humpback whales are known to inhabit cooler, high-latitude waters when foraging and low-latitudes for mating and calving. Beyond this general migratory pattern, a number of demographic characteristics including, abundance, distribution, seasonal occurrence, and prey preferences remain unknown or poorly described. A complete understanding of humpback whale ecology is therefore lacking. Many methods used to explore these aspects of cetacean ecology are either prohibitively expensive or limited in the scope of what can be learned from their …

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Impact Of Scale-Up On Science Teaching Self-Efficacy Of Students In General Education Science Courses, Mary Kay Cassani Jan 2008

Impact Of Scale-Up On Science Teaching Self-Efficacy Of Students In General Education Science Courses, Mary Kay Cassani

Electronic Theses and Dissertations

The objective of this study was to evaluate the effect of two pedagogical models used in general education science on non-majors' science teaching self-efficacy. Science teaching self-efficacy can be influenced by inquiry and cooperative learning, through cognitive mechanisms described by Bandura (1997). The Student Centered Activities for Large Enrollment Undergraduate Programs (SCALE-UP) model of inquiry and cooperative learning incorporates cooperative learning and inquiry-guided learning in large enrollment combined lecture-laboratory classes (Oliver-Hoyo & Beichner, 2004). SCALE-UP was adopted by a small but rapidly growing public university in the southeastern United States in three undergraduate, general education science courses for non-science majors …

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The Spiritual Competency Scale: A Comparison To The Aservic Spiritual Competencies, Linda Robertson Jan 2008

The Spiritual Competency Scale: A Comparison To The Aservic Spiritual Competencies, Linda Robertson

Electronic Theses and Dissertations

Spiritual and religious beliefs are significant aspects of a person's worldview and have been well established within many disciplines as a resource for physical and mental health. Therefore, they are relevant topics for counselors. The governing bodies of the counseling profession support the discussion of these beliefs in counseling. To meet the ethical mandates for competency in this area, the Association for Spiritual, Ethical, and Religious Values in Counseling (ASERVIC) produced the Spiritual Competencies. Despite these efforts, spiritual and religious material continues to be neglected in counselor training programs. In the absence of a formal measure of spiritual competency, curricular …

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Closing The Achievement Gap For English Language Learners:A Comparison Of Language Arts/Esol And One-Way Developmental Bilingual, Kimberly Marlow Jan 2008

Closing The Achievement Gap For English Language Learners:A Comparison Of Language Arts/Esol And One-Way Developmental Bilingual, Kimberly Marlow

Electronic Theses and Dissertations

The present study was conducted to investigate two English Language Learner programs in one Florida county and their implications for student achievement. The literature review showed that, as students progress through the educational system, the academic content becomes more and more abstract, forcing students to rely more heavily on their oral and written communication skills in English. Significant achievement gaps, sometimes extremely large, were also identified between English-only students and English Language Learner students. One study highlighted a 46% gap on the 2005 National Assessment of Education Progress (NAEP). The present study was designed to investigate 23 middle schools in …

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Effects Of Orthophosphate Corrosion Inhibitor In Blended Water Quality Environments, Erica Stone Jan 2008

Effects Of Orthophosphate Corrosion Inhibitor In Blended Water Quality Environments, Erica Stone

Electronic Theses and Dissertations

This study evaluated the effects of orthophosphate (OP) inhibitor addition on iron, copper, and lead corrosion on coupons exposed to different blends of groundwater, surface water, and desalinated seawater. The effectiveness of OP inhibitor addition on iron, copper, and lead release was analyzed by statistical comparison between OP treated and untreated pilot distribution systems (PDS). Four different doses of OP inhibitor, ranging from zero (control) to 2 mg/L as P, were investigated and non-linear empirical models were developed to predict iron, copper, and lead release from the water quality and OP doses. Surface characterization evaluations were conducted using X-ray Photoelectron …

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The Effects Of Informal Science Education On Students' Attitudes And Academic Performance, Samuel Ashley Jan 2008

The Effects Of Informal Science Education On Students' Attitudes And Academic Performance, Samuel Ashley

Electronic Theses and Dissertations

Will student attitudes towards science change when they are given a chance to explore an area of science in which they have indicated an interest? This action research thesis investigated this question over a period of nine weeks. The subjects of this study included twelve students enrolled in the same seventh grade physical science class. The school was located in a suburban setting in the Southeast United States. Data for this study was collected with anecdotal notes, participation grid, science attitude survey, student interviews, and student journals. This study found that when students are given the opportunity to pursue an …

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Modeling Transmission Dynamics Of Tuberculosis Including Various Latent Periods, Tracy Atkins Jan 2008

Modeling Transmission Dynamics Of Tuberculosis Including Various Latent Periods, Tracy Atkins

Electronic Theses and Dissertations

The systems of equations created by Blower et al. (1995) and Jia et al. (2007) designed to model the dynamics of Tuberculosis are solved using the computer software SIMULINK. The results are first employed to examine the intrinsic transmission dynamics of the disease through two models developed by Blower et al. (1995). The "simple transmission model" was used primarily to give insight to the behavior of the susceptible, latent, and infectious groups of individuals. Then, we consider a more detailed transmission model which includes several additional factors. This model captures the dynamics of not only the susceptible, latent and infectious …

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Design And Experimental Study Of An Integrated Vapor Chamber -" Thermal Energy Storage System, Krishna Kota Jan 2008

Design And Experimental Study Of An Integrated Vapor Chamber -" Thermal Energy Storage System, Krishna Kota

Electronic Theses and Dissertations

Future defense, aerospace and automotive technologies involve electronic systems that release high pulsed waste heat like during high power microwave and laser diode applications in tactical and combat aircraft, and electrical and electronic systems in hybrid electric vehicles, which will require the development of an efficient thermal management system. A key design issue is the need for fast charging so as not to overheat the key components. The goal of this work is to study the fabrication and technology implementation feasibility of a novel high energy storage, high heat flux passive heat sink. Key focus is to verify by theory …

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Evaluating Tactical Combat Casualty Care Training Treatments Effects On Combat Medic Trainees In Light Of Select Human Descripti, Teresita Sotomayor Jan 2008

Evaluating Tactical Combat Casualty Care Training Treatments Effects On Combat Medic Trainees In Light Of Select Human Descripti, Teresita Sotomayor

Electronic Theses and Dissertations

The use of military forces in urban operations has increased considerably over the past years. As illustrated by the current conflict in Iraq, the Army finds itself fighting its toughest battles in urban areas facing unconventional forces. Soldiers face many threats in hostile fire environments, whether conducting large-scale mechanized warfare, low-intensity conflicts, or operations other than war. Through 1970, there has been no demonstrable reduction in battlefield mortality rate as a percentage of all casualties since data was kept since before the Civil War. For that period of time, nearly all the reduction in overall mortality rate occurred through reduced …

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Evaluation Of The Antecedents Of Cultural Competence, Mary Harper Jan 2008

Evaluation Of The Antecedents Of Cultural Competence, Mary Harper

Electronic Theses and Dissertations

Purpose: The threefold purpose of this research is to identify the essential antecedents of cultural competence as identified by international nurse researchers, to compare the content of the extant cultural competence instruments to these antecedents and to potentially identify gaps in their conceptualization. A secondary aim of this research is to initiate validation of Harper's model of ethical multiculturalism. Conceptual Basis: The model of ethical multiculturalism depicts the attributes of ethical multiculturalism as the fulcrum of a balance between two ethical philosophies of fundamentalism and relativism. The attributes of moral reasoning, beneficence/nonmaleficence, respect for persons and communities, and cultural competence …

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Sex Education Policy In Florida: Strategies For Change, Jenna Cawley Jan 2008

Sex Education Policy In Florida: Strategies For Change, Jenna Cawley

Electronic Theses and Dissertations

Sex education policies and programs in Florida are largely dominated by the abstinence-only approach. This paper makes the case that abstinence-only education is a failing policy in Florida, and evaluates strategies advocates may use in order to accomplish reform. Three different strategies are evaluated: countywide school district reform, statewide rejection of federal abstinence-only funding, and statewide standardization of sex education via legislation. Contrasts are drawn between all three strategies with regard to their potential impact on sex education policy in Florida, viability, and the challenges they present to advocates. This paper concludes that statewide standardization of sex education in Florida …

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Cross-Modal Effects In Tactile And Visual Signaling, James Merlo Jan 2008

Cross-Modal Effects In Tactile And Visual Signaling, James Merlo

Electronic Theses and Dissertations

Using a wearable tactile display three experiments were conducted in which tactile messages were created emulating five standard US Army and Marine arm and hand signals for the military commands, namely: "Attention", "Halt", "Rally", "Move Out", and "Nuclear Biological or Chemical event (NBC)". Response times and accuracy rates were collected for novices responding to visual and tactile representations of these messages, which were displayed either alone or together in congruent or incongruent combinations. Results indicated synergistic effects for concurrent, congruent message presentations showing superior response times when compared to individual presentations in either modality alone. This effect was mediated by …

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Moderators Of Trust And Reliance Across Multiple Decision Aids, Jennifer Ross Jan 2008

Moderators Of Trust And Reliance Across Multiple Decision Aids, Jennifer Ross

Electronic Theses and Dissertations

The present work examines whether user's trust of and reliance on automation, were affected by the manipulations of user's perception of the responding agent. These manipulations included agent reliability, agent type, and failure salience. Previous work has shown that automation is not uniformly beneficial; problems can occur because operators fail to rely upon automation appropriately, by either misuse (overreliance) or disuse (underreliance). This is because operators often face difficulties in understanding how to combine their judgment with that of an automated aid. This difficulty is especially prevalent in complex tasks in which users rely heavily on automation to reduce their …

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The Impact Of Organizational Politics On Mentoring Relationships, Nicholas Bencaz Jan 2008

The Impact Of Organizational Politics On Mentoring Relationships, Nicholas Bencaz

Electronic Theses and Dissertations

Mentoring in the workplace has become an increasingly popular trend because of its touted success at addressing the career and social related needs of employees. While the majority of the research on mentoring has examined protege benefits, far fewer studies have examined the potential negative effects of mentoring. Moreover, little is known about the antecedents of negative mentoring experiences. A primary objective of the present study was to investigate relations between mentor and protege perceptions of organizational politics and reports of functional and dysfunctional mentoring. In addition, I examined the joint contribution of functional and dysfunctional mentoring to a number …

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Meshless Hemodynamics Modeling And Evolutionary Shape Optimization Of Bypass Grafts Anastomoses, Zaher El Zahab Jan 2008

Meshless Hemodynamics Modeling And Evolutionary Shape Optimization Of Bypass Grafts Anastomoses, Zaher El Zahab

Electronic Theses and Dissertations

Objectives: The main objective of the current dissertation is to establish a formal shape optimization procedure for a given bypass grafts end-to-side distal anastomosis (ETSDA). The motivation behind this dissertation is that most of the previous ETSDA shape optimization research activities cited in the literature relied on direct optimization approaches that do not guaranty accurate optimization results. Three different ETSDA models are considered herein: The conventional, the Miller cuff, and the hood models. Materials and Methods: The ETSDA shape optimization is driven by three computational objects: a localized collocation meshless method (LCMM) solver, an automated geometry pre-processor, and a genetic-algorithm-based …

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Evaluation Of Climatic And Ecohydrological Effects On Longwave Radiation And Evapotranspiration, Maria Rizou Jan 2008

Evaluation Of Climatic And Ecohydrological Effects On Longwave Radiation And Evapotranspiration, Maria Rizou

Electronic Theses and Dissertations

Modern tools, nontraditional datasets and a better understanding of the interaction between climate and ecohydrology are continuously being developed as today's society is in critical need for improving water management, predicting hydrometeorological hazards and forecasting future climate. In particular, the study of the intra- and inter-annual variations in grass productivity and evapotranspiration caused by variations in precipitation/soil moisture and other biophysical factors is of great significance due to their relation to future climatic changes. The research presented here falls in three parts. In the first part of the dissertation, a land use adaptable model, based on the superposition of the …

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Sustainable Fault-Handling Of Reconfigurable Logic Using Throughput-Driven Assessment, Carthik Sharma Jan 2008

Sustainable Fault-Handling Of Reconfigurable Logic Using Throughput-Driven Assessment, Carthik Sharma

Electronic Theses and Dissertations

A sustainable Evolvable Hardware (EH) system is developed for SRAM-based reconfigurable Field Programmable Gate Arrays (FPGAs) using outlier detection and group testing-based assessment principles. The fault diagnosis methods presented herein leverage throughput-driven, relative fitness assessment to maintain resource viability autonomously. Group testing-based techniques are developed for adaptive input-driven fault isolation in FPGAs, without the need for exhaustive testing or coding-based evaluation. The techniques maintain the device operational, and when possible generate validated outputs throughout the repair process. Adaptive fault isolation methods based on discrepancy-enabled pair-wise comparisons are developed. By observing the discrepancy characteristics of multiple Concurrent Error Detection (CED) configurations, …

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Modeling Lane-Based Traffic Flow In Emergency Situations In The Presence Of Multiple Heterogeneous Flows, Amani Saleh Jan 2008

Modeling Lane-Based Traffic Flow In Emergency Situations In The Presence Of Multiple Heterogeneous Flows, Amani Saleh

Electronic Theses and Dissertations

In recent years, natural, man-made and technological disasters have been increasing in magnitude and frequency of occurrence. Terrorist attacks have increased after the September 11, 2001. Some authorities suggest that global warming is partly the blame for the increase in frequency of natural disasters, such as the series of hurricanes in the early-2000's. Furthermore, there has been noticeable growth in population within many metropolitan areas not only in the US but also worldwide. These and other facts motivate the need for better emergency evacuation route planning (EERP) approaches in order to minimize the loss of human lives and property. This …

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Alayzing The Effects Of Modularity On Search Spaces, Ozlem Garibay Jan 2008

Alayzing The Effects Of Modularity On Search Spaces, Ozlem Garibay

Electronic Theses and Dissertations

We are continuously challenged by ever increasing problem complexity and the need to develop algorithms that can solve complex problems and solve them within a reasonable amount of time. Modularity is thought to reduce problem complexity by decomposing large problems into smaller and less complex subproblems. In practice, introducing modularity into evolutionary algorithm representations appears to improve search performance; however, how and why modularity improves performance is not well understood. In this thesis, we seek to better understand the effects of modularity on search. In particular, what are the effects of module creation on the search space structure and how …

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Development Of Hydraulic And Soil Properties For Soil Amendments And Native Soils For Retention Ponds In Marion County, Florida, Lisa Naujock Jan 2008

Development Of Hydraulic And Soil Properties For Soil Amendments And Native Soils For Retention Ponds In Marion County, Florida, Lisa Naujock

Electronic Theses and Dissertations

The vadose zone plays an important role in managing stormwater. Predicting the water balance and water movement is crucial in ground water remediation to keep water suitable for use. To aid in understanding soils ability to transmit and store water, soil and hydraulic properties were analyzed for soils in Marion County, Florida, and potential soil amendments. Soil and hydraulic properties were examined for two soil amendments and for the soils in Marion County, Florida, at the South Oak and the Hunter's Trace locations. The hydraulic properties measured were the soil moisture retention curve (SMRC) and saturated hydraulic conductivity (Ks). The …

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Reducing Effluent Phosphorus And Nitrogen Concentrations From A Stormwater Detention Pond Using A Chamber Upflow Filter And Skim, Patrick Ryan Jan 2008

Reducing Effluent Phosphorus And Nitrogen Concentrations From A Stormwater Detention Pond Using A Chamber Upflow Filter And Skim, Patrick Ryan

Electronic Theses and Dissertations

Stormwater runoff is a known pollutant source capable of causing surface water degradation, especially in highly populated areas such as Central Florida. Wet detention ponds manage this stormwater, but most of the ponds do not remove enough nutrients, specifically nitrogen and phosphorus, to meet TMDL regulations. This research provides a possible addition to a detention pond in Seminole County, Florida using a Chamber Upflow Filter and Skimmer (CUFS), which can increase the removal of phosphorus and nitrogen by the system. Water enters the system through the skimmer, which floats on the surface of the detention pond. It travels from the …

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Developmemnt Of A Modeling And Simulation Training Needs Model For Selected Defense Acquisition Workforce Communities, Lik Chun Peh Jan 2008

Developmemnt Of A Modeling And Simulation Training Needs Model For Selected Defense Acquisition Workforce Communities, Lik Chun Peh

Electronic Theses and Dissertations

The DoD Modeling and Simulation Steering Committee (M&S SC) identified Modeling and Simulation (M&S) as an educational objective for the Acquisition, Technology and Logistics (AT&L) workforce. Notably, past usages of M&S in system acquisitions for both DoD and commercial industry have demonstrated improvements in efficiency and effectiveness over traditional acquisition techniques. However, to achieve expected and consistent performance by this workforce in these new techniques, the M&S essential skill requirements for this workforce may be extensive. This research aims to validate the content and level of competency in selected M&S tools and technology necessary for consistent workforce performance. The notion …

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Determining Florida Landfill Odor Buffer Distances Using Aermod, Veronica Figueroa Jan 2008

Determining Florida Landfill Odor Buffer Distances Using Aermod, Veronica Figueroa

Electronic Theses and Dissertations

As U.S. landfills continue to grow in size, concerns about odorous gas emissions from landfills are increasing. For states that are expanding in population, such as Florida, odors from landfills are a major concern because new housing developments, needed to accommodate the rapid population growth, are creeping closer and closer to the existing landfills. As homes get closer to landfills, odor complaints are likely to become more frequent, causing landfill managers increased problems with public interactions. Odor buffer zones around landfills need to be established to give municipalities tools to help prevent the building of future homes too close to …

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Integration Of A Nanostructure Embedded Thermoresponsive Polymer For Microfluidic Applications, Ghanashyam Londe Jan 2008

Integration Of A Nanostructure Embedded Thermoresponsive Polymer For Microfluidic Applications, Ghanashyam Londe

Electronic Theses and Dissertations

This work describes the modeling, synthesis, integration and characterization of a novel nanostructure embedded thermoresponsive material for microfluidic applications. The innumerable applications of thermoresponsive surfaces in the recent years have necessitated the development of a rigorous mathematical treatment for these surfaces to understand and improve their behavior. An analytical model is proposed to describe the transfer characteristic (variation of contact angle versus temperature) of a unique switchable, nanostructured, thermoresponsive surface consisting of silica nanoparticles and the thermoresponsive polymer, Poly(N-isopropylacrylamide ) (PNIPAAm) which changes its wetting angle upon heating. Important metrics such as the absolute lower critical solution temperature, threshold & …

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User-Defined Patterning Of Neural Progenitor Cells On 3d Micropillar Arrays Using Round Cross-Sectional Geometry, Specific Dimen, Andrea Wesser Jan 2008

User-Defined Patterning Of Neural Progenitor Cells On 3d Micropillar Arrays Using Round Cross-Sectional Geometry, Specific Dimen, Andrea Wesser

Electronic Theses and Dissertations

The ability to control stem cell functions, particularly neuronal progenitors, has long since been believed to be the key to successful treatment of neurodegenerative disorders such as Alzheimer's, Parkinson's and accidents involving head trauma. The neurology field calls for many new solutions to address the controlled neural stem cell seeding and placement of cells for neural tissue regeneration. Self-assembled monolayers (SAM) from the alkanethiol group provide a straightforward applicable, reliable treatment for cell adhesion. An ODT/gold treatment was used to adhere the cells to patterned areas, due mainly to a high confluence of cells attracted to it, as well as …

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