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Modeling Of Realistic Heart Electrical Excitation Based On Dti Scans And Modified Reaction Diffusion Equation, Ihab Elaff

Turkish Journal of Electrical Engineering and Computer Sciences

A new method is proposed for modeling realistic heart activation using diffusion tensor imaging (DTI) scans based on biological properties of its tissues in addition to the working methodology of the DTI scanner. Modeling of the excitation propagation inside the heart is initiated by applying activation at only one pacing site at the root of the conduction network. The excitation propagation has been accomplished based on a proposed conduction system that is extracted from DTI heart scans and a modified version of monodomain reaction diffusion equation (RDE) that considers the heart inhomogeneous--anisotropic material. The Aliev--Panfilov method was used to model …

Human P450 Cyp17a1: Control Of Substrate Preference By Asparagine 202, Michael C. Gregory, Piotr J. Mak, Yogan Khatri, James R. Kincaid, Stephen G. Sligar

Chemistry Faculty Research and Publications

CYP17A1 is a key steroidogenic enzyme known to conduct several distinct chemical transformations on multiple substrates. In its hydroxylase activity, this enzyme adds a hydroxyl group at the 17α position of both pregnenolone and progesterone at approximately equal rates. However, the subsequent 17,20 carbon–carbon scission reaction displays variable substrate specificity in the numerous CYP17A1 isozymes operating in vertebrates, manifesting as different K_d and k_cat values when presented with 17α-hydroxypregnenlone (OHPREG) versus 17α-hydroxyprogesterone (OHPROG). Here we show that the identity of the residue at position 202 in human CYP17A1, thought to form a hydrogen bond with the A-ring alcohol …

Image Reconstruction For Frequency-Domain Diffuse Optical Tomography, Vicky Mudeng, Yun Priyanto, Andhika Giyantara

Turkish Journal of Electrical Engineering and Computer Sciences

The image reconstruction algorithm of diffuse optical tomography (DOT) is based on the diffusion equation and involves both the forward problem and inverse solution. The forward problem solves the diffusion equation using the finite element method for calculating the transmitted light distribution under the condition of presumed light source and optical coefficient. The inverse solution reconstructs the optical property coefficient distribution using Newton's method. The work within this study develops an image reconstruction algorithm for frequency-domain DOT. A numerical simulations approach to light propagation in the tissue is conducted, while the optical property is reconstructed employing data around the boundary. …

Human Sleep Scoring Based On K-Nearest Neighbors, Shahnawaz Qureshi, Seppo Karrila, Sirirut Vanichayobon

Turkish Journal of Electrical Engineering and Computer Sciences

Human sleep is one of the essential indicators that gauge the overall health and well-being. Presently, it is common for people to face issues related to sleep. Various biomedical signals including electroencephalogram (EEG), electrooculography (EMG), and electrooculography (EOG) are utilized in the diagnosis and during the treatment of sleep disorder cases. An automatic classification to diagnose sleep problems can help in the analysis of sleep EEG data. In this current study, an effort is made to classify the sleep stages from a single EEG channel (C4-A1) based on K-nearest neighbors (K-NN) with three alternative distance metrics. The Euclidean distance is …

Studies On Selected Enzymes Involved In Ubiquinone Biosynthesis In Escherichia Coli, Debarati Ghose

Graduate Research Theses & Dissertations

Escherichia coli synthesize an important component of the electron transport chain, Coenzyme Q (Ubiquinone; Q) from the shikimate pathway intermediate, chorismate. Two isofunctional enzymes UbiD and UbiX are responsible for the decarboxylation step in Q biosynthesis. It was shown by Gulmezian et al. (2007) that the loss of ubiX+ gene leads to a reduction in growth in both rich and minimal media as well as decrease in Q. They further reported that UbiX is responsible for controlling the activity of UbiG O-methyltransferase, involved in two O-methylation reactions in Q biosynthesis. Contrary to these results, in this study we show that …

Rewriting Spinsterhood : Single Women In American And British Women's Novels Since 1960, Kimberly Volmer

Graduate Research Theses & Dissertations

This dissertation argues that stereotypes about the Victorian spinster continue to influence the depiction of the single woman in American and British literature since 1960. Perceived as a threat to heteronormative culture, the single woman protagonist must contend with stereotypes of the "old maid" and the "spinster" that culminate in three characteristics of single woman fiction: that the protagonist is perceived as an object of speculation, that she must answer for her singlehood, and that she should find work caring for a surrogate family. Writers engage in several narrative strategies to deflect, revise, and occasionally reinscribe stereotypes of single womanhood. …

Responding To Small Island Nations Imperiled By Human-Forced Climate Change: An Ethical Imperative For Christians, Jame Schaefer

Theology Faculty Research and Publications

Small island nations are increasingly imperiled by larger nations that are emitting most of the greenhouse gases, forcing changes in the global climate, and causing catastrophic ecological and social problems. Among the most adversely affected people are islanders who are suffering immense health, economic, and cultural injustices that should be addressed at all levels of governance. Leaders of Anglican, Eastern Orthodox, and Roman Catholic denominations have been responding meaningfully to the plight of the small island nations by drawing motivation from their theological traditions for mitigating the problems and calling all Christians to act individually, collectively within their parishes, and …

Converting To And Nurturing Ecological Consciousness--Individually, Collectively, Actively, Jame Schaefer

Theology Faculty Research and Publications

No abstract provided.

Gendered Language And The Construction Of Jewish Identity In 2 Maccabees, Joshua Ezra Burns

Theology Faculty Research and Publications

No abstract provided.

Converting To And Nourishing Ecological Consciousness-Individually And Collectively, Jame Schaefer

Theology Faculty Research and Publications

No abstract provided.

Water Supply Planning In Virginia: The Future Of Groundwater And Surface Water, Jonathon Lubrano, Jeffrey Moore

Virginia Coastal Policy Center

This paper begins by exploring the current state of water resources planning and permitting. Then, considers current water demand in Virginia, as well as future challenges. Next is an examination of management structures from other states and a discussion of potential solutions to the water scarcity issue, including wastewater purification, the Hampton Roads Sanitation District’s (HRSD) Sustainable Water Initiative For Tomorrow (SWIFT) project, and desalination. The paper concludes with various next steps and policy recommendations that the Commonwealth should consider as dwindling water resources could hamper economic growth and threaten drought conditions, such as regional planning to achieve the optimal …

New Approaches To Cyclopentadienyl-Fused Thiophene Complexes Of Iron And Synthesis And Characterization Of Carbonic Anhydrase Active-Site Mimics For Co2 Hydration, Deepshikha Gupta

Theses and Dissertations--Chemistry

Polyheterocycles such as polythiophene and its derivatives comprise an important class of conducting polymers used for electronic applications. They have been of great interest for use in electronic materials due to their increased environmental stability as well as novel electronic properties in their polymer states. We have been interested in exploring the electronic properties of organometallic analogues of the low-band-gap polymer poly(benzo[3,4-c]thiophene) (polyisothianaphthene) that incorporates η⁵-cyclopenta[c]thienyl monomers such as ferroceno[c]thiophene. First chapter of this dissertation involved synthetic attempts to ferroceno[c]thiophene. Exploring a shorter synthetic route to starting material, 1,2-di(hydroxymethyl)ferrocene was …

Assembly And Trafficking Of The Cystic Fibrosis Transmembrane Conductance Regulator And Associated Proteins, Zhihui Zhang

Theses and Dissertations--Chemistry

Cystic Fibrosis (CF) is an autosomal recessive genetic disease that leads to severe malfunction in many organs, but particularly the lungs. The primary cause of this malfunction is the decrease of the airway surface liquid layer on the lung epithelium. The lack of hydration leads to mucus build up on the epithelial lining, leading to blockage of airways. The underlying cause of CF is the dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR), which results from mutations in the protein. Almost 90% of CF patients are caused by the deletion of the phenylalanine at position 508 of CFTR, which …

Enhanced Analysis Of Lignin Dehydrogenation Oligomers Via Mass Spectrometry, Amber Suzanne Bowman

Theses and Dissertations--Chemistry

Effective analytical techniques need to be developed to characterize the products of lignin degradation experiments to be able to generate renewable products from lignin. Mass spectrometry is an valuable analytical approach for lignin characterizaion, but it is hindered by lignin’s poor ionization efficiency, especially in the positive ion mode. In this work, we attempt to improve lignin’s ionization by utilizing electrospray and laser desorption mass spectrometry coupled with the addition of cations and chemical derivatives. We confronted the ionization problem from both a top-down and bottom-up analytical approach by analyzing synthesized monomers, dimers, and polymers along with natural lignin extracts …

Design, Synthesis And Biological Evaluation Of Inhibitors Against Both Human And Mouse Microsomal Prostaglandin E2 Synthase-1 Enzymes, Kai Ding

Theses and Dissertations--Chemistry

As the principal pro-inflammatory prostanoid, prostaglandin E₂ (PGE₂) serves as mediator of pain and fever in inflammatory reactions. The biosynthesis of PGE₂ starts from arachidonic acid (AA). Cyclooxygenase (COX)-1 and/or COX-2 converts AA to prostaglandin H₂ (PGH₂), and PGE₂ synthases transform PGH₂ to PGE₂. Current mainstream approach for treating inflammation-related symptoms remains the application of traditional non-steroidal anti-inflammatory drugs (tNSAIDs) and selective COX-2 inhibitors (coxibs). As both categories shut down the biosynthesis of all downstream prostanoids, their application renders several deleterious effects including gastrointestinalulceration and cardiovascular risk. Microsomal prostaglandin …

Increasing Living Shoreline Implementation In Virginia: Legal And Policy Recommendations, Christopher Antoine

Virginia Coastal Policy Center

When living shorelines are correctly implemented, they can provide a number of benefits to landowners, localities, and the state. Based on that knowledge, in 2011, the Virginia General Assembly codified a preference for the use of living shorelines in tidal shoreline stabilization projects to facilitate a greater realization of those benefits. Despite the statutory preference, much of Virginia’s tidal shoreline may not be realizing the benefits associated with living shorelines. A recent report from the Center for Coastal Resources Management (CCRM) at the Virginia Institute of Marine Science indicated that, in a sample of coastal Virginia localities from 2014-2016, as …

Women And The Experience Of Pain And Opioid Use Disorder: A Literature-Based Commentary, Andrew L. Koons, Marna R. Greenberg Do, Mph, Facep, Robert D. Cannon Do, Gillian A. Beauchamp Md

Department of Emergency Medicine

It is generally understood that pain experience and opioid abuse have relied on male-dominated models. However, sex and gender play a role in both pain experience and opioid use disorder.

Using the previously validated Texas Tech University Health Sciences Center Sex and Gender Specific Health PubMed Advanced Search Tool, the authors used pertinent literature to develop this literature-based commentary on sex and gender differences in pain experience and opioid use disorder. Women report their experience of pain more frequently, have increased rates of diagnoses related to pain, have increased pain sensitivity, and have a variable response to pain and analgesia. …

The Bulletin: Sidney Kimmel Medical College At Thomas Jefferson University, Volume 67, Issue 1, Winter 2018

The Bulletin (formerly the Jefferson Medical College Alumni Bulletin)

This issue includes:

• Dean's Column
• Findings: "Living Electrodes" may change neurological device design
• Ch-ch-ch-changes: Jefferson's realignment of departments and programs
• The Difference Alumni Make: A message from Elizabeth Dale
• A Fighting Chance: Harrisburg's boxing scene has an unlikely ally in cardiologist Andrew Foy, MD '08
• Alumni Weekend
• 2017 Jefferson Gala: Gathering to celebrate our shared success
• Time Capsule
• The Shot Doc: Meet Herb Magee, head coach of Jefferson's men's basketball team, the Rams
• Going the Distance: Students bring compassion into the clinic in Nicaragua's remote mountains
• On Campus
• Stephanie Moleski, MD '05: Jefferson doctor moves from board room to exam …

Reconstructing Insect Pursuit Flight Kinematics In The Wild, Haribabu Boddeeti

Graduate Research Theses & Dissertations

With their agile maneuvers and aerodynamic feats, flying insects continue to inspire the design, sensing, and control of unmanned aerial vehicles. Among the different behaviors that such insects perform, the mating pursuit stands out in terms of the high speeds and quick turns that each insect performs during the chase. Despite their frequent occurrence in nature, pursuit events between mating insects are rarely analyzed. This is because mating events are difficult to film in the wild or elicit in laboratory settings. The long-term goal of this research is to quantify the kinematics of flying insects in pursuit. The specific objective …

Multifunctional Nanocomposites In Coating Technology: Synthesis, Characterization, Formulation, Evaluation And Application, Sudeshna Chakraborty

Graduate Research Theses & Dissertations

Application of Nanomaterials using nanotechnology has gained significant

attention in the coating industry in recent years. Their application has had a great

impact, particularly in the 3C industries (computer, communication, and construction).

Incorporation of nanomaterials into polymer carriers through a systematic approach to

coating processes can enhance various physical properties, such as mechanical,

optical, electrical and thermal properties. The current dissertation focused on the

synthesis and characterization of new nanomaterials like mesoporous silica or

nanocomposites like copper-doped zinc oxide that can be used in the coating to study

thermal cooling performance and enhancement of thermal conductivity. New thermal

devices will …

Effects Of Management On Functional Diversity In Restored Tallgrass Prairie Plant Communities, Anna K. Farrell

Graduate Research Theses & Dissertations

While recent studies have embraced evaluating ecosystems through functional diversity, the focus on interspecific trait changes may limit their usefulness and application. Functional traits (traits that explain species’ responses to environmental conditions and their ecosystem roles) can provide a more nuanced understanding of how disturbances shape plant communities and the functions they perform. Further, the inclusion of intraspecific trait responses can explain a significant portion of these relationships. In ecosystem restorations, management strategies can act as environmental drivers and disturbances that affect community structure. This study examined how three environmental drivers (grazer presence, prescribed fire, and age) in restored grasslands …

Evaluation Of Ispe For Inhibitor Design In The Non-Mevalonate Pathway, Kataryzna Barbara Hoerchler

Graduate Research Theses & Dissertations

There is an urgent need to discover new antibiotics to combat the emergence of drug resistant Novel antibiotics that target unique pathways different from existing therapies are promising targets. The non-mevalonate pathway (MEP), which was discovered in the 1990’s, is essential for most bacteria, plants and apicomplexan parasites. Inhibition of the non-mevalonate is an attractive pharmaceutical target, since it is not present in mammals. Many compounds have surfaced as potential inhibitors, but none have made it to market. This thesis investigates the fourth step in the MEP pathway involving the enzyme 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase (IspE) from Escherichia coli (Ec), Burkholderia thailandensis …

Investigating The Effects Of Orientation Control Of Graphene Nanoplatelet Suspensions By A Magnetic Field On The Viscosity Of A Nanofluid System, Radhika Iyer

Graduate Research Theses & Dissertations

In this investigation, the rheological behavior of paraffin oil containing diamagnetic suspensions is characterized under varying magnetic field conditions. The particles suspended in the white paraffin oil at mass concentrations of 0.1, 0.3, 0.5, 0.7 and 1% m/m are two-dimensional graphene nanoplatelets with an average thickness of 2 – 8 nm. Rheological experiments were conducted using a Brookfield DV2T viscometer with a modified cylindrical spindle over the range of shear rates between 192 s-1 to 1928 s-1. A Neodymium N42 ring magnet with a surface strength of 1.32 T generated the magnetic field conditions for the rheological experiments and was …

Don't Take 'No' For An Answer, Beth Liechti

Mighty Pen Project Anthology & Archive

Two veterans, an retired Army officer and a World War II Women's Army Corp veteran. find common ground in the bonds of shared military service.

Articles, stories, and other compositions in this archive were written by participants in the Mighty Pen Project. The program, developed by author David L. Robbins, and in partnership with Virginia Commonwealth University and the Virginia War Memorial in Richmond, Virginia, offers veterans and their family members a customized twelve-week writing class, free of charge. The program encourages, supports, and assists participants in sharing their stories and experiences of military experience so both writer and audience …

A Tongan Cultural Model Of Identity, Tevita Molisi Manu'atu

Graduate Research Theses & Dissertations

This thesis examines Tongan people's assumptions and perspectives about the Tongan identity as expressed through discourse in relations to the subject. The data from these discourses were collected by conducting semi-structured interviews with twenty-eight participants from various backgrounds, focusing on two representative populations; The Kingdom of Tonga and the United States of America. The collective data was then analyzed using cultural model theory and background as a framework. This thesis examines how Tongan identity is affected from the perspectives of Tongans themselves, and what the shared conceptualization---cultural model---of Tongan identity is. This study uncovered five main components of the Tongan …

A Transverse-Wakefield Streaking Technique For Measurement Of Ultra-Fast Electron Pulses, Jinlong Wang

Graduate Research Theses & Dissertations

The development of future free electron lasers (FELs) requires reliable time-resolved measurements of ultrashort (less than ps) electron-bunches, especially their temporal distribution. A possible technique is to streak the bunch in the transverse direction by means of time-dependent external electromagnetic fields. A passive deflector, consisting of a dielectriclined waveguide, is used to produce electromagnetic wakefield that impart a time-dependent transverse kick to a relativistic electron bunch that propagates off-axis. The present work explores the possible use of the self-generated electromagnetic fields.

Student, Instructor, And Observer Agreement Regarding Frequencies Of Scientific Teaching Practices Using The Measurement Instrument For Scientific Teaching-Observable (Misto), Mary F. Durham, Jennifer Knight, Emily K. Bremers, Jameson D. Defreece, Alex R. Paine, Brian A. Couch

School of Biological Sciences: Faculty Publications

Background: The Scientific Teaching (ST) pedagogical framework encompasses many of the best practices recommended in the literature and highlighted in national reports. Understanding the growth and impact of ST requires instruments to accurately measure the extent to which practitioners implement ST in their courses. Researchers have typically relied on students, instructors, or observers to document course teaching practices, but it remains unclear whether and how these perspectives differ from each other. To address this issue, we modified our previously published instrument to generate the Measurement Instrument for Scientific Teaching-Observable (MISTO), which can be completed by students, instructors, and observers, and …

Development Of A Multi-Robot Testbed For Direct Human-Swarm Interaction, Venkata Satya Kiran Maridi

Graduate Research Theses & Dissertations

Robotic swarms are well suited for missions that involve covering large areas such as environmental monitoring, search-and-rescue operations, as well as those that require fusing information from multiple sources such as target tracking and machine inspection. However, navigating a swarm of robots effectively requires performing higher-level functions that are typically executed by humans such as commanding them to stay close and guiding them along with a preplanned route. In this context, the ability of multiple robots to stay together autonomously significantly reduces the cognitive load on a human operator. The goal of this thesis is to design and build a …

Exploring African American Students’ Perceptions Of Belonging At An Urban Community College In The Western United States, Sylinda Nicole Gordon Musaindapo

Graduate Research Theses & Dissertations

African American students’ perceptions of belonging impact their experiences on community college campuses and in their local communities. This research study explores the impact of gentrification on a group of resilient African American college students in an urban community college located in the western region of the United States. Participants used negative experiences with onlyness and otherness as opportunities to build community for other African Americans.

Cohens On The Move: Jewish Residential Dynamics In Cincinnati, Ohio, 1940-2000, Carmi J. Neiger

Graduate Research Theses & Dissertations

In the 1960s and 1970s, as many large US cities experienced rapid racial and ethnic demographic shifts, the intra-urban residential settlement and migration patterns of American Jews came to the attention of sociologists and urbanists. Although the interest in this population has waned in favor of more recent immigrant groups, patterns of Jewish residential dynamics continue to evolve, reflecting changes over time in both Jewish religious and ethnic identity and assimilation into mainstream American society. The lack of Census data identifying households by religious affiliation requires an alternative approach to the study of this group. In the first section of …