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Microstructure Evolution And Tem In Situ Mechanical Testing Of Proton Irradiated Nanocrystalline Copper Tantalum Alloy, Priyam Patki May 2018

Microstructure Evolution And Tem In Situ Mechanical Testing Of Proton Irradiated Nanocrystalline Copper Tantalum Alloy, Priyam Patki

Open Access Theses

Nanocrystalline alloys have always fascinated researchers due to their enhanced properties as compared to their bulk counterparts. There has been a rising interest in the nanocrystalline CuTa alloy system due to its high grain stability for temperatures up to 0.7Tm. In the scope of this thesis we studied the microstructure evolution of proton irradiated Cu-10%Ta 700⁰C and we performed TEM in situ mechanical. Microstructure studies showed increase in phase size with increase in dose, defect imaging in Transmission electron microscope (TEM) showed presence of Stacking Fault Tetrahedra (SFT) with an average size of 4 nm and a number density of …

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Organic Smallholder Farming In Northwest Vietnam: A Case Study From Tan Lac District, Hoa Binh Province, Linh Dieu Pham May 2018

Organic Smallholder Farming In Northwest Vietnam: A Case Study From Tan Lac District, Hoa Binh Province, Linh Dieu Pham

Open Access Theses

This study asks whether organic vegetable production is a suitable alternative farming practice for conventional vegetable farmers in Tan Lac, a mountainous area in the North of Vietnam. The study is motivated by three questions: (1) who among the vegetable farmers in Tan Lac tended to switch to organic vegetable production? (2) is organic vegetable production profitable, compared with conventional production? And (3), what could be done to make organic vegetable production a more sustainable source of income and to help farmers switching to organic farming be more successful? These questions are answered using quantitative and qualitative data collected from …

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A Snapshot Of Vocabulary Recycling: How German Language Textbooks Treat Vocabulary, Kailey Preston May 2018

A Snapshot Of Vocabulary Recycling: How German Language Textbooks Treat Vocabulary, Kailey Preston

Open Access Theses

This study is an investigation into vocabulary recycling in beginning-level German language textbooks. Vocabulary recycling, or the reuse of previously introduced vocabulary words, is important in foreign language education because several “meetings” with a word (up to sixteen), both within a few days and across a longer period of time, are required for successful acquisition of a word (Pimsleur, 1967; Saragi, Nation & Meister, 1978; Nation, 2001). Attention to vocabulary recycling in the sphere of foreign language education is fairly new. However, investigations in Spanish and EFL contexts found that vocabulary recycling is largely insufficient and that instructors are aware …

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The Development Of Information Assurance And Cyber Security Competencies, La'reshia Poe May 2018

The Development Of Information Assurance And Cyber Security Competencies, La'reshia Poe

Open Access Theses

Information assurance and cybersecurity has become a critical element in the daily lives of almost every individual and organization across the globe. To be able to protect Personal Identity Information (PII), Intellectual Property (IP) and organizational trademarks requires producing more cybersecurity practitioners. The problem being addressed by this study is the identification of comprehensive competency levels for information assurance and cybersecurity practitioners is unknown. This research created definitions for three levels of cybersecurity practitioners that can be utilized by government, industry and academia individuals and organizations. 14 core competencies for cybersecurity practitioners were identified and defined. The Qualtrics survey was …

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A Review Of Frp Repair And Strengthening Methods For Application To Indiana Bridges, Jon M. Pevey May 2018

A Review Of Frp Repair And Strengthening Methods For Application To Indiana Bridges, Jon M. Pevey

Open Access Theses

According to the most recent ASCE Infrastructure Report Card, many of the bridges in the United States are approaching the end of their design lives. For these bridges, reparative action needs to be taken to ensure the structural performance is adequate for the demand imposed. If repair or rehabilitation is not feasible, then replacement of a component or structure is necessary. To avoid the costly process of component or system replacement, methods of rehabilitation have been established using conventional materials and procedures. Although these industry-proven methods are useful, many of the procedures have issues with long-term performance and constructability. An …

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Responsibly Persuaded: An Exploration Of The Ethics Of Persuasive Technology, Joseph E. Price May 2018

Responsibly Persuaded: An Exploration Of The Ethics Of Persuasive Technology, Joseph E. Price

Open Access Theses

The pervasiveness of technology comes with an increased risk for negative outcomes. Responsibility must fall upon designers to anticipate problems and guarantee positive outcomes. The concept of design character is the basis from which they assume responsibility. The goal of this study was twofold. First, I sought to understand how designers persuade users or stakeholders, and through what means. Second, I sought to critically evaluate aspect of persuasive design through the lens of ethics and values. This study provides an understanding of the criteria and philosophies of ethics relied upon to evaluate persuasive technology. To address both research goals, a …

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The Effects Of Card Playing On Cognition, Julia Nicole Bergmann May 2018

The Effects Of Card Playing On Cognition, Julia Nicole Bergmann

Open Access Theses

The present study aimed to examine the potential effects of card playing and socialization on cognition. Participants completed a battery of cognitive tests in order to obtain a baseline of cognitive function. Each participant was randomized to one of three training paradigms: group socialization, group card playing, and individual card playing. The socialization group met once a week for an hour for eight weeks and discussed topics of their choice. The card playing groups played Hearts either in a group or on the computer for one hour a week for eight weeks. After eight weeks of their training, participants completed …

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Advanced Torque Control Strategy For The Maha Hydraulic Hybrid Passenger Vehicle., Pranay Banerjee May 2018

Advanced Torque Control Strategy For The Maha Hydraulic Hybrid Passenger Vehicle., Pranay Banerjee

Open Access Theses

An increase in the number of vehicles per capita coupled with stricter emission regulations have made the development of newer and better hybrid vehicle architectures indispensable. Although electric hybrids have more visibility and are now commercially available, hydraulic hybrids, with their higher power densities and cheaper components have been rigorously explored as the alternative. The most commonly used architecture is the series hybrid, which requires a power conversion from the primary source (engine) to the secondary domain. A positive displacement machine (pump) converts the rotational power of the engine into hydraulic power and a second positive displacement machine (motor) converts …

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A Lexically Driven Taxonomy For Political Campaign Interactions On Twitter, Joshua Curth May 2018

A Lexically Driven Taxonomy For Political Campaign Interactions On Twitter, Joshua Curth

Open Access Theses

Political candidates continuously develop new techniques for communicating to their targeted publics effectively through social media. One way to do so is through Twitter. This exploratory study maps Aristotelian rhetorical appeals to electoral tweets issued in the 2016 presidential election. Using automatic and human coding, the study proposes four different types of Twitter rhetorical appeals. Results show 58.8% of tweets issued during the presidential election are captured by the rhetorical taxonomy. The findings also show that the primary appeals both candidates use in both mass and salience did not always influence intention to vote. Finally, there are correlations between contextually …

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Using Corn Zein To Improve The Quality Of Gluten-Free Bread, Aminata Diatta May 2018

Using Corn Zein To Improve The Quality Of Gluten-Free Bread, Aminata Diatta

Open Access Theses

Cereals are the most highly produced crops in the world and their storage proteins account for up to 50% of the total protein necessary for the nutrition of humans. As the number of people with celiac disease grows and diagnosis of the disease is improved, the development of high quality gluten-free foods is very important. Zein, the prolamin of maize (Zea mays L.) is used in this study in combination with starches to replace some of the functionality of wheat gluten. Zein can be made viscoelastic when it is freed and separated from protein bodies, and when it is moistened …

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Turbopump Testing And Diagnostics, Andres Porro Carvalhar May 2018

Turbopump Testing And Diagnostics, Andres Porro Carvalhar

Open Access Theses

Liquid-propelled rocket engines are the current state-of-the-art in the space propulsion industry. Turbopumps are used to deliver the necessary engine conditions to ensure the large chamber pressurization that liquid-propelled systems require. As there is no record of any full-scale development of a rocket turbopump in academia, Purdue University and its Maurice J. Zucrow Propulsion Laboratories launched the Turbopump Project with the objective of designing, building, and testing a turbopump with engine-relevant conditions. This thesis briefly outlines turbomachinery design processes along with a brief overview of Purdue’s Turbopump Project design that started in 2013. The thesis mainly provides the complete testing …

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Measuring Environmental Effects On Lora Radios In Cold Weather Using 915 Mhz, Austin Riegsecker May 2018

Measuring Environmental Effects On Lora Radios In Cold Weather Using 915 Mhz, Austin Riegsecker

Open Access Theses

The “Internet of Things” (IoT) is a commonplace term in today’s society. Measuring our homes, cities, and farm land, IoT devices and sensor networks help give insight with new amounts and types of data collected. With several billion devices projected to be in use by 2020, an inexpensive, reliable solution for communication is needed. Typically, this would mean Wi-Fi, and in the home that works; but what if the devices are several miles away? LoRaWAN has sought to fll this need, however, appears unreliable given changes in atmospheric conditions. Experiments in Europe have shown a complete communication breakdown when temperatures …

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Comparison Of Machine Learning Algorithms And Their Ensembles For Botnet Detection, Songhui Ryu May 2018

Comparison Of Machine Learning Algorithms And Their Ensembles For Botnet Detection, Songhui Ryu

Open Access Theses

A Botnet is a network of compromised devices controlled by a botmaster often for nefarious purposes. Analyzing network traffc to detect Botnet traffc has historically been an effective approach for systems monitoring for network intrusion. Although such system have been applying various machine learning techniques, little investigation into a comparison of machine algorithms and their ensembles has been undertaken. In this study, three popular classifcation machine learning algorithms – Naive Bayes, Decision tree, and Neural network – as well as the ensemble methods known to strengthen said classifers are evaluated for enhanced results related to Botnet detection. This evaluation is …

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Objective Identification And Tracking Of Zdr Columns In X-Band Radar Observations, Patrick Evan Saunders May 2018

Objective Identification And Tracking Of Zdr Columns In X-Band Radar Observations, Patrick Evan Saunders

Open Access Theses

With the advent of rapidly scanning radar systems, it is imperative to automate the detection of features in radar images. We discuss efforts to objectively identify ZDR columns in X-band radar observations using the enhanced watershed algorithm (EWA; Lakshmanan et al. 2009), a method for identifying features in geospatial images. We discuss our choices for EWA parameters, including thresholds. The EWA is applied to ZDR observations of convective storms obtained during the 2016 and 2017 VORTEX-SE field campaign by the University of Massachusetts X-band, polarimetric, mobile Doppler radar (UMass X-Pol). During several intensive observing periods (IOPs), a variety of convective …

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User Adoption Of Home Automation Technology, Pranavi Settipalle May 2018

User Adoption Of Home Automation Technology, Pranavi Settipalle

Open Access Theses

Technological advancements are redefining what is possible every day. There are various products in the market that have the potential to improve the quality of living when understood and used right. Yet a lot of people resist changes in their digital usage. The first cell phone was released in the same decade as home automation was proposed. The reason for the cell phone’s success and home automation’s failure is user adoption. The initial cell phones were underdeveloped and had their problems, but wide acceptance allowed for research to develop them into what we use today, and that has changed our …

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Impact Ignition Mechanisms And Sensitization Of An Aluminized Fluorinated Acrylic (Alfa) Nanocomposite, Ian A.J. Shelburne May 2018

Impact Ignition Mechanisms And Sensitization Of An Aluminized Fluorinated Acrylic (Alfa) Nanocomposite, Ian A.J. Shelburne

Open Access Theses

Tailoring the reliability of impact ignited reactive materials continues to be an elusive challenge. Ideally, a sensitizing agent is preferred over device or reactive ingredient modification. Here, we report Asay shear impact studies of aluminized fluorinated acrylic (AlFA) and material sensitization via the introduction of inert particles. Initial Asay shear impact testing of neat AlFA50 yielded a general baseline for material ignition at approximately 120 m/s for the configuration considered. Ignition was observed to occur on the far wall or in corners indicating that a pinching mechanism may be responsible. A modified experimental setup was used to image the response …

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Bionode5.0: A Miniature, Wireless, Closed-Loop Biological Implant For Neuromodulation, Gang Seo May 2018

Bionode5.0: A Miniature, Wireless, Closed-Loop Biological Implant For Neuromodulation, Gang Seo

Open Access Theses

The needs for electrotherapy, using electrical devices, are significantly increasing, due to limitations that pharmaceutical therapies may have, such as unignorable side effects and meager side effects on a multitude of cardiovascular and neurological diseases. To research on electrotherapy using an implantable electronic module, a miniature, wireless, and closed-loop implantable device, called "Bionode", has been developed at Center for Implantable Device, directed by Dr. Pedro Irazoqui. Bionode4.1, the most recent version of the Bionode, is a device that consists of three different printed circuit boards(PCB), including a wireless communication system, an inductive power receiving system, and a two-channel recording system …

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The Influence Of Carrier Water Ph On Efficacy Of Fungicides For Turf Disease Control, Trevor R. Stacy May 2018

The Influence Of Carrier Water Ph On Efficacy Of Fungicides For Turf Disease Control, Trevor R. Stacy

Open Access Theses

Fungicides are most often mixed with water and applied as a dilute spray for controlling diseases on golf course turf. Although published reports show that water quality can influence the performance of certain herbicides, evidence of similar effects on fungicide efficacy is weak and largely anecdotal. The objective of this research was to investigate the influence of water pH on efficacy of fungicides commonly used against dollar spot, a problematic disease on creeping bentgrass. In this study, three fungicides (metconazole, thiophanate-methyl, and iprodione) were mixed with water stabilized at three pH levels (pH= 5.0, 7.0, and 9.0) in in vitro …

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Cooperative Planning System For Self-Separation In En-Route Airspace, Varun S. Sudarsanan May 2018

Cooperative Planning System For Self-Separation In En-Route Airspace, Varun S. Sudarsanan

Open Access Theses

The increase in flight density and the need to integrate Unmanned Areal Vehicles into the National Airspace demands higher flexibility. Distributing the conflict detection and resolution (CD&R) functions among the aircraft ensures a greater flexibility in the flight plans for the aircraft. A co-operative planning system is proposed for separation assurance by distributing the CD&R in the en-route airspace among a fully-connected network of aircraft. The aircraft cooperate to achieve the common goal of conflict-free trajectories, while attempting to reduce the disruptions from their original flight plans. A pairwise CD&R algorithm is developed through heuristics which is then implemented iteratively …

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The Importance Of Power, Distance, And Imposition On Spanish Verb Forms In Requests, Bruno Staszkiewicz Garcia May 2018

The Importance Of Power, Distance, And Imposition On Spanish Verb Forms In Requests, Bruno Staszkiewicz Garcia

Open Access Theses

This thesis analyzed the production of requests through the framework of Politeness Theory and the variables of power, distance, and imposition (Brown & Levinson, 1987). Research on Spanish has focused on Spanish requests (e.g. Placencia, 1998; Lorenzo Díaz, 2016) or cross-cultural analyses of requests (e.g. Blum-Kulka, House & Kasper, 1989; Márquez-Reiter, 2000). However, the lack of balance in the contexts examined regarding the social variables power, distance, and imposition makes it difficult to compare the effect of these variables on the request norms. Furthermore, requests likely vary according to other contextual factors as well, but this has received little systematic …

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Deep Neural Network Regression And Sobol Sensitivity Analysis For Daily Solar Energy Prediction Given Weather Data, Yixuan Sun May 2018

Deep Neural Network Regression And Sobol Sensitivity Analysis For Daily Solar Energy Prediction Given Weather Data, Yixuan Sun

Open Access Theses

Solar energy forecasting plays an important role in both solar power plants and electricity grid. The effective forecasting is essential for efficient usage and management of the electricity grid, as well as for the solar energy trading. However, many of the existing models or algorithms are based on real physical laws, where tons of calculations, step-by-step modification, and many inputs are required. In this research, a novel deep Multi-layer Perceptron (MLP) based regression approach for predicting solar energy is proposed, in which the inputs are only ensemble weather forecasting data. The results demonstrate that our proposed deep Multi-layer Perceptron based …

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Energy Dashboard For Evaluating Performance Of Net Zero Energy Buildings, Megan M. Switzer May 2018

Energy Dashboard For Evaluating Performance Of Net Zero Energy Buildings, Megan M. Switzer

Open Access Theses

People spend the majority of their day inside a building but remain unaware of the complex inner workings shaping their indoor environment. Energy dashboards simplify thousands of building data points to allow users to improve and understand the performance of their buildings. Traditionally, energy dashboards have had a more limited role in facility management in terms of monitoring performance, detecting sensor malfunctions, and identifying broken equipment. Smart buildings are expected to become a 137-billion-dollar market within the next five years, energy dashboards are needed to interface with homes and offices. Increasingly, energy dashboards are developed to actively manage and optimize …

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Sentiment Analysis On Financial News And Microblogs, Chinmay Talekar May 2018

Sentiment Analysis On Financial News And Microblogs, Chinmay Talekar

Open Access Theses

Sentiment analysis is useful for multiple tasks including customer satisfaction metrics, identifying market trends for any industry or products, analyzing reviews from social media comments. This thesis highlights the importance of sentiment analysis, provides a summary of seminal works and different approaches towards sentiment analysis. It aims to address sentiment analysis on financial news and microblogs by classifying textual data from financial news and microblogs as positive or negative. Sentiment analysis is performed by making use of paragraph vectors and logistic regression in this thesis and it aims to compare it with previously performed approaches to performing analysis and help …

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Adaptive Sampling Fixed-Step And Line Search Methods For Stochastic Optimization, Hui Tan May 2018

Adaptive Sampling Fixed-Step And Line Search Methods For Stochastic Optimization, Hui Tan

Open Access Theses

where the function f or its gradient rf are not directly accessible except through Monte Carlo estimates, we present three solution algorithms: fixed-step for infinite population sampling, fixed-step for finite population sampling, and line search for infinite population sampling. The salient feature of each of these algorithms is that the Monte Carlo sampling is adaptive to the algorithm trajectory, sampling little when the algorithm iterates are assessed to be far away from a first-order critical point and sampling more when the algorithm iterates are assessed to be close to a first-order critical point. We show that a specific form of …

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Engineering Genetically Encoded Sensors To Study Purinergic Signaling, Stephen Valentino May 2018

Engineering Genetically Encoded Sensors To Study Purinergic Signaling, Stephen Valentino

Open Access Theses

Extracellular adenosine triphosphate (ATP) is a key purinergic signal that mediates cell-to cell communication both within and between organ systems. We address the need for a robust and minimally invasive approach to measuring extracellular ATP by re-engineering the ATeam ATP sensor to be expressed on the cell surface. Using this approach, we image real-time changes in extracellular ATP levels with a sensor that is fully genetically-encoded and does not require an exogenous substrate. Using live-cell microscopy, we characterize sensor performance when expressed on cultured Neuro2A cells, and we measure both stimulated release of ATP and its clearance by ectonucleotidases. In …

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Multicore Xinu, Philip M. Van Every May 2018

Multicore Xinu, Philip M. Van Every

Open Access Theses

Multicore architectures employ multiple processing cores that work together for greater processing power. Shared memory, symmetric multiprocessor (SMP) systems are ubiquitous. All software must be explicitly designed to support SMP processing, including operating systems. XINU is a simple, lightweight, elegant operating system that has existed for several decades and has been ported to many platforms. However, XINU has never been extended to support multicore processing. This project incrementally adds SMP support to the XINU operating system. Core kernel modules, including the scheduler and memory manager, have been successfully extended without overhauling or completely redesigning XINU. A multicore methodology is laid …

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Parametric Study Of A 7◦ Half-Angle Cone With Highly-Swept Fins At Mach 6, Franklin D. Turbeville May 2018

Parametric Study Of A 7◦ Half-Angle Cone With Highly-Swept Fins At Mach 6, Franklin D. Turbeville

Open Access Theses

Boundary-layer instability and transition was measured on a 7◦ cone with highly-swept fins at 0◦ angle of attack in a Mach-6 quiet tunnel. Effects of fin sweep angle, fin bluntness, and nosetip radius were assessed. Using temperature-sensitive paint and piezoelectric fast pressure transducers, transition was measured in all configurations. Some features present under quiet flow were not seen under noisy flow. Multiple streaks of heat transfer with peaks near 5 kW/m2 were noted on the cone surface. More streaks appeared and the streaks spread as the Reynolds number increased. Power spectral density plots were calculated from the pressure transducer data …

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Performance Enhancement Of Logistic Regression For Big Data On Spark, Mengyao Wang May 2018

Performance Enhancement Of Logistic Regression For Big Data On Spark, Mengyao Wang

Open Access Theses

This research proposes a new ftting algorithm of logistic regression on IRWLS that utilizes the procedure of scanning data row-by-row and has the ability to acquire an exact result with only a few iterations. Furthermore, this research also realizes the distributed parallelization of the proposed method on Spark and conducts various experiments to manifest its memory-wise advantage over the traditional methods such as Spark MLlib package. The results show that the proposed method can provide an exact result rather than an approximated one within 5 or 6 iterations; achieve a satisfying accuracy for fight delay prediction within 1 or 2 …

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Behavior Of Planar Concrete-Filled Composite Plate Shear Walls For High-Rise Buildings, April Y. Wang May 2018

Behavior Of Planar Concrete-Filled Composite Plate Shear Walls For High-Rise Buildings, April Y. Wang

Open Access Theses

Concrete-Filled Composite Plate Shear Walls (CF-CPSW) consist of pre-fabricated steel modules filled with plain concrete. During construction, the empty steel modules are designed to support multiple floors of the steel framing before the concrete is infilled, and they act as permanent formwork. CF-CPSW systems can lead to improved constructability and reduced construction schedules. In coupled CF-CPSW lateral force resisting systems, the coupled walls resist global over turning moment through an axial force couple and individual wall flexural resistance. Therefore, in order to design the coupled CF-CPSW system, the wall’s flexural behavior under axial load must be evaluated. This study reports …

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Mathematical Model Of Interstitial Fluid Flow And Characterization Of The Lacunar Canalicular System In Cortical Bone, Melanie B. Venderley May 2018

Mathematical Model Of Interstitial Fluid Flow And Characterization Of The Lacunar Canalicular System In Cortical Bone, Melanie B. Venderley

Open Access Theses

While the mechanotransductive capability of skeletal tissue has been acknowledged for decades, the exact mechanisms that enable bone to sense and respond to external stimuli have remained elusive. Numerous theories have evolved to explain this behavior, most notably those involving fluid movement through the tissue’s hierarchical structure. Within mineralized bone, osteocytes reside in micro and nanoporosities, known as lacunae and canaliculi, which house the cell body and their long cellular processes, respectively. Through this lacunar-canalicular system (LCS), osteocytes form an interconnected network, which allow signaling and communication with surrounding osteocytes via gap junctions and secreted factors. It has been theorized …

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