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Model Driven Optimization of Drug Delivery for Spinal Cord Injury
Get PDFSpinal cord injuries have an annual new case incidence in the United States of up to 40 cases per million population, with a 36.2% 10 year survival rate in patients over 50 years old. Barely half of survivors from 40 to 60 can perform activities of daily living, regardless of the severity of the initial injury. [1] Spinal cord injury is progressive, mediated by secondary injury, or a subacute inflammatory process that is poorly understood. [2-4] Secondary injury can involve or lead to apoptosis, scarring, cavitation, ischemia, and demyelination, among other sequelae, and many of these are not conducive to neuronal recovery. [4] Therefore there is a need for improved ways of addressing secondary injury mechanisms in these patients. [2] Minocycline can target multiple secondary injury mechanisms through its anti-inflammatory, anti-oxidative, and anti-apoptotic effects. [5-7] However, it is only fully effective at high concentrations. At the systemic levels required for this, minocycline can cause liver toxicity and even death. [8] Minocycline can form self-assembling, water insoluble particles with dextran sulfate and divalent metal cations, with high entrapment efficiency and a stable, slow release. There is potential for a controllable vehicle for drug delivery to optimize dosing with minocycline. [8] Predicting minocycline release behavior of a complex system can be performed by the creation of a model to simplify the system to an equation. This simplification can be guided by a combination of theoretical frameworks and previous empirical data that suggests idealized ratios between the components; previous work suggests the highest entrapment efficiency given a 1.2:1 mass concentration ratio of dextran sulfate:minocycline, in the presence of 7.2 mM Mg2+, suggesting saturation of binding sites at these values. [8] With a high degree of accuracy, this model can help direct the optimization of the drug delivery system. In the case of minocycline:dextran sulfate:Mg2+, the model proposed in this study was able to predict the trend of behavior but not with enough sensitivity for small dosing changes that characterize this delivery method. Biomedical engineering is an interdisciplinary field that combines understanding of various scientific and design expertise. In order to tailor a drug delivery system, as well as help to characterize the mechanism of release, generating a simple model can provide insight to the behavior of the system while reducing time, labor, and cost.M.S., Biomedical Engineering -- Drexel University, 201
Decision Fusion in Non-stationary Environments
Get PDFA parallel distributed detection system consists of multiple local sensors/detectors that observe a phenomenon and process the gathered observations using inbuilt processing capabilities. The end product of the local processing is transmitted from each sensor/detector to a centrally located data fusion center for integration and decision making. The data fusion center uses a specific optimization criterion to obtain global decisions about the environment seen by the sensors/detectors. In this study, the overall objective is to make a globally-optimal binary (target/non-target) decision with respect to a Bayesian cost, or to satisfy the Neyman-Pearson criterion. We also note that in some cases a globally-optimal Bayesian decision is either undesirable or impractical, in which case other criteria or localized decisions are used. In this thesis, we investigate development of several fusion algorithms under different constraints including sequential availability of data and dearth of statistical information. The main contribution of this study are: (1) an algorithm that provides a globally optimal solution for local detector design that satisfies a Neyman-Pearson criterion for systems with identical local sensors; (2) an adaptive fusion algorithm that fuses local decisions without a prior knowledge of the local sensor performance; and (3) a fusion rule that applies a genetic In addition, we develop a parallel decision fusion system where each local sensor is a sequential decision maker that implements the modified Wald's sequential probability test (SPRT) as proposed by Lee and Thomas (1984).Ph.D., Electrical Engineering -- Drexel University, 201
How Technological Innovation in Media Provokes Industry and Regulatory Change
No full textThe purpose of this thesis was to gain insight into the technology and regulation that is deeply ingrained in the television and media industries. Through two interviews conducted in Philadelphia, two industry professionals provided opinion and insight into the current landscape of television and media. Their deep understanding of the media industry landscape and the technological influences within this industry added support to trends already being documented. The key stakeholders that make up the television and media industry are evolving as is the technology that supports the industry and the stakeholders alike. Regulation of an industry that is evolving presents challenges for current legislation and in implementing new legislation. This thesis provides insights to understand past roles and decisions, present issues and direction for possible future changes.M.S., Television Management -- Drexel University, 201
Employee Onboarding, Development, and Retention In Theatre
Get PDFThis paper examines the Human Resource concepts of Employee Onboarding, Development, and Retention as they relate to the theater. Through an examination of current market research, scholarly sources, and an original qualitative survey this study sheds light on the lack of writing, research, and strong professional practice in these areas of Human Resources and attempts to answer the following questions: What role does HR play in regards to Employee Onboarding, Development and Retention in the theater? What practices are lacking in these areas? What HR practices do theater professionals feel are important to their work? This study concludes that many of your standard HR practices such as monitoring employee behavior, attendance, adherence to rules, even incident reporting, safety protocols, and emergency procedures all exist but are handle by Stage Managers and not Human Resource professionals. This study also concludes that theatre professionals find an organization’s reputation, the content produced, and the organization’s culture as key reasons for continued employment at any given theater.M.S., Arts Administration -- Drexel University, 201
A Wake-Up Call to Recovery: Drug Abuse and Its Effect on Registered Nurses: A Narrative Study
No full text"You are as close to a miracle as you are to a tragedy.
I wanted to be a miracle and not a tragedy." (Jasmine Jade)
Recovery for nurses is vital to the health of society and is considered a gift by those nurses who have experienced the devastation of drug addiction and its consequences. There is a great illusion in society and among nurses themselves that they are immune to addiction. Throughout history, the nursing profession has been identified as one of the most trusted professions in society, yet studies have concluded that out of the estimated 2.8 million nurses currently working in the U.S., 10% to 20% (280,000 to 560,000) of those working in the nursing profession have experiences with substance use disorders. This is a serious issue, as nurses with substance use disorders are the most hidden population in society and place patients at risk.
This narrative study gives voice to nurses who are in recovery and who were willing to share information regarding their journey to recovery and the impact substance use has had on their personal and professional lives. It illuminates nurses' experiences and provides information regarding their own understanding of their personal risks for substance abuse and how the systems of support within their healthcare settings helped them address their substance abuse issues. Seven registered nurses in California who were in recovery for a minimum of two years agreed to participate in multiple face-to-face interviews. The interviews were transcribed, coded, and organized using Atlas.ti (qualitative software). The data were analyzed, and findings and interpretations from the participants' voices aligned with the conceptual framework, guided by the research questions, emerged into five themes: (a) family dynamics and patterns; (b) substance use disorders in nurse education and within the nurse profession; (c) illusions and secrets of the nurse professional; (d) confrontational "crisis" and the "wake-up call;" and (e) recovery, spiritual awakenings and recovery communities. Major findings within the research reveal serious inadequacies within the nursing profession for identifying, intervening, and supporting nurses with substance use disorders. The findings also underscore the impact recovery communities have on nurses who have major risks factors for substance abuse. Nurses need a critical wake-up-call to jolt them from addiction to sobriety. This jolt can provide them with the clarity needed to embrace treatment and ultimately recovery. Recommendations are outlined for educators, administrators, and other policymakers about increasing awareness, public safety, and training to identify and support nurses with substance use disorders. Recovery community support is vital, as it provides the connections and lifestyle change needed to enable a nurse to maintain his or her sobriety and develop into a healthy, productive member of the healthcare community.Ed.D., Educational Leadership and Management -- Drexel University, 201
Phytosterol Cyclopamine Rescues Structural and Behavioral Deficits in a Drosophila model of Alzheimer's Disease
Get PDFThe average person spends several hours a day behind the wheel of their vehicles, which are usually equipped with on-board computers capable of collecting real-time data concerning driving behavior. However, this data source has rarely been tapped for healthcare and behavioral research purposes. This MS thesis is done in the context of the Diagnostic Driving project, an NSF funded collaborative project between Drexel, Children Hospital of Philadelphia (CHOP) and the University of Central Florida that aims at studying the possibility of using driving behavior data to diagnose medical conditions. Specifically, this paper introduces focuses on the classification of driving behavior data collected in a driving simulator using deep neural networks. The target classification task is to differentiate novice versus expert drivers. The paper presents a comparative study on using different variants of LSTM (Long-Short Term Memory networks) and Auto-encoder networks to deal with the fact that we have a small amount of labels (16 examples of people driving in the simulator, each labeled with an 'expert' or 'inexpert' label), but each simulator drive is high dimensional and too densely sampled (each drive consists of 100 variables sampled at 60Hz). Our results show that using an intermediate number of neurons in the LSTM networks and using data filtering (only considering one out of each 10 samples) obtains better results, and that using Auto-encoders works worse than using manual feature selection.M.S., Biological Sciences -- Drexel University, 201
Model-Based Usability Analysis of Safety-Critical Systems: A Formal Methods Framework
Get PDFComplex, safety-critical systems are designed with a broad range of automated and configurable components, and usability problems often emerge for the end user during setup, operation, and troubleshooting procedures. Usability evaluations should consider the entire human-device interface including displays, controls, hardware configurations, and user documentation/procedures. To support the analyst, human factors researchers have developed a set of methods and measures for evaluating human-system interface usability, while formal methods researchers have developed a set of model-based technologies that enable mathematical verification of desired system behaviors. At the intersection of these disciplines, an evolving set of model-based frameworks enable highly automated verification of usability early in the design cycle. Models can be abstracted to enable broad coverage of possible problems, while measures can be formally verified to "prove" that the system is usable. Currently, frameworks cover a subset of the target system and user behaviors that must be modeled to ensure usability: procedures, visual displays, user controls, automation, and possible interactions among them. Similarly, verification methodologies focus on a subset of potential usability problems with respect to modeled interactions. This work provides an integrated formal methods framework enabling the holistic modeling and verification of safety-critical system usability. Building toward the framework, a set of five, novel approaches extend the capabilities of extant frameworks in different ways. Each approach is demonstrated in a medical device case study to show how the methods can be employed to identify potential usability problems in existing systems. A formal approach to documentation navigation models an end user navigating through a printed or electronic document and verifies page reachability. A formal approach to procedures in documentation models an end user executing steps as written and aids in identifying problems involving what device components are identified in task descriptions, what system configurations are addressed, and what temporal orderings of procedural steps could be improved. A formal approach to hardware configurability models end-user motor capabilities, relationships among the user and device components in the spatial environment, and opportunities for the user to physically manipulate components. An encoding tool facilitates the modeling process, while a verification methodology aids in ensuring that configurable hardware supports correct end- user actions and prevents incorrect ones. A formal approach to interface understandability models what information is provided to the end user through visual, audible, and haptic sensory channels, including explanations provided in accompanying documentation. An encoding tools facilitates the development of models and specifications, while the verification methodology aids in ensuring that what is displayed on the device is consistent; and, if needed, an explanation of what is displayed is provided in documentation. A formal approach to controlled actuators leverages an existing modeling technique and data collected from other engineering activities to model actuator dynamics mapping to referent data. An encoding tool facilitates model development, and a verification methodology aids in validating the model with respect to source data. Finally, new methodologies are combined within the integrated framework. A model architecture supports the analyst in representing a broad range of interactions among constituent framework models, and a set of ten specifications is developed to enable holistic usability verification. An implementation of the framework is demonstrated within a case study based on a medical device under development. This application shows how the framework could be utilized early in the design of a safety-critical system, without the need for a fully implemented device or a team of human evaluators.Ph.D., Biomedical Science -- Drexel University, 201
On the Synthesis & Characterization of Ti3C2Tx MXene Polymer Composites
Get PDFAn investigation into the synthesis and characterization of T i3C2Tx MXene polymer composites has been made, where an improvement in material properties at low filler weight percents has been achieved. Poly(acrylic acid) based composite material showed improved mechanical performance, namely a 144.8% increase in tensile strain to failure with no reduction in elastic modulus and only slight reduction in ultimate tensile strength. FTIR analysis of these films show evidence for hydrogen bonding between the functional groups of poly(acrylic acid) and the surface functionalization of T i3C2Tx. Nylon-6 based composites loaded at 5 and 10 wt% MXene were successfully produced by both a solvent cast and extrusion method, with MXene content verified by thermogravimetric analysis (TGA). Samples loaded at 5 wt% exhibited a 30.96% increase in modulus of elasticity, with a 10.9% increase in ultimate tensile strength. A water barrier phenomena was observed in the case of these MXene containing composites, as evidenced by the characteristic shape of the stress-strain plot. Differential scanning calorimetry results reveal a 15 ◦C increase in the crystallization temperature (Tc) with a enthalpy of crystallization 18% lower than neat nylon-6 and a degree of crystallinity of 60-70%, suggesting that MXene acts as a site for heterogeneous nucleation. X-ray diffraction results indicate that full delamination of multilayer MXene was not achieved through mechanical shearing alone, however improved mechanical properties were achieved despite this, suggesting that further improvements could be made if full exfoliation is achieved.M.S., Materials Science and Engineering -- Drexel University, 201
Redox-active Hybrid Materials for Pseudocapacitive Energy Storage
Get PDFOrganic-inorganic hybrid materials show a great promise for the purpose of manufacturing high performance electrode materials for electrochemical energy storage systems and beyond. Molecular level combination of two best suited components in a hybrid material leads to new or sometimes exceptional sets of physical, chemical, mechanical and electrochemical properties that makes them attractive for broad ranges of applications. Recently, there has been growing interest in producing redox-active hybrid nanomaterials for energy storage applications where generally the organic component provides high redox capacitance and the inorganic component offers high conductivity and robust support. While organic-inorganic hybrid materials offer tremendous opportunities for electrochemical energy storage applications, the task of matching the right organic material out of hundreds of natural and nearly unlimited synthetic organic molecules to appropriate nanostructured inorganic support hampers their electrochemical energy storage applications. We aim to present the recent development of redox-active hybrid materials for pseudocapacitive energy storage. We will show the impact of combination of suitable organic materials with distinct carbon nanostructures and/or highly conductive metal carbides (MXenes) on conductivity, charge storage performance, and cyclability. Combined experimental and molecular simulation results will be discussed to shed light on the interfacial organic-inorganic interactions, pseudocapacitive charge storage mechanisms, and likely orientations of organic molecules on conductive supports. Later, the concept of all-pseudocapacitive organic-inorganic asymmetric supercapacitors will be highlighted which open up new avenues for developing inexpensive, sustainable, and high energy density aqueous supercapacitors. Lastly, future challenges and opportunities to further tailor the redox-active hybrids will be highlighted.Ph.D., Materials Science and Engineering -- Drexel University, 201
Creative Placemaking as a Guide to Redevelopment in Detroit
No full textPrevious research on creative placemaking has established the practice as challenging, divisive, and problematic. Without focusing on what creative placemaking could do, prior research describes what creative placemaking should stop doing. When creative placemaking is presented as a positive, effective practice, the evaluation and criteria for selection is fuzzy, without providing enough measurable context on how change is accomplished. I introduce a new creative placemaking framework that identifies twelve criteria that assist in rejuvenating the local economy, combating race and inequality in a post-industrial Detroit, and adopting major ideas of past planning and development strategies. To accomplish this research, I developed a new evaluation framework and analyzed three differently defined creative placemaking programs in Detroit, including a comprehensive mapping component. I found that Detroit’s current creative placemaking strategies are capable of actualizing the criteria set within this research in varying ways. The three programs vary in definition, outcome, project selection, and evaluation; however, each program does not consistently demonstrate the ability to extend critical factors to the marginalized, self-managed residents of Detroit. Given this, I recommend a new program similar in approach to ArtPlace that persistently enhances city systems, increases livability factors to the marginalized, increases social capital, and discourages gentrification and displacement in Detroit.M.S., Arts Administration -- Drexel University, 201