bluuebunny/crossref_metadata_2025 huggingface dataset:
The Potential for Competition Between the Red-bellied Turtle (Pseudemys rubriventris) and the Red-eared Slider Turtle (Trachemys scripta elegans)
Authors:   , Pearson Steven H. , Avery Harold W. , Spotila James Robert
Published: July 2021

Invasive species are a significant cause of biodiversity declines on a global scale and novel species interactions often cause ecological damage through predation or competition. The red-eared slider turtle (Trachemys scripta elegans) has been introduced to wetlands globally and negatively impacts other native turtle species. In Pennsylvania, USA, the red-eared slider turtle is ecologically similar to the PA, state threatened red-bellied turtle (Pseudemys rubriventris). The objective of this dissertation is to examine the potential for competition between red-eared slider turtles and red-bellied turtles using field studies of adult free ranging turtles and manipulative studies of juvenile turtles in mesocosms. Field studies utilized intensive trapping, radio telemetry, stomach flushing, fecal sample collection and stable isotopes to determine populations sizes, spatial resource use and dietary resource use of both species. Intensive trapping and radio telemetry revealed that both species used wetland habitats ubiquitously. Dietary studies revealed that at a smaller, more highly fragmented and vegetative species depauperate wetland complex, red-eared slider turtles and red-bellied turtles overlapped extensively for dietary resources while at a larger, intact, more vegetative species rich wetland the diets of both species were partitioned. In manipulative experiments in which red-eared slider turtles and red-bellied turtles were housed in low resource availability groups and high resource availability groups with conspecifics or in mixed species groups red-eared slider turtles were competitively superior to red-bellied turtles. Field study results suggest that the potential for competition between red-eared slider turtles and red-bellied turtles varies depending on local habitat characteristics, while manipulative experiment results suggest that red-eared slider turtles are competitively superior in resource limited environments. These results combined suggest that in degraded wetland habitats, when resources become limited, red-eared slider turtles will have a competitive advantage over red-bellied turtles potentially leading to population declines. Red-eared slider turtles should not be sold outside of their native range as pets and when possible they should be removed from wetland habitats outside of their native range. Furthermore, wetland habitats should be managed and preserved to provide intact, species rich and species diverse habitats.
The Effects of Biomimetic Proteoglycans On Interstitial Flow-Induced Cancer Invasion
Authors:   , Kasbekar Priyanka Pratod , Shieh Adrian C.
Published: July 2021

Local microenvironments play a crucial role in cancer biology and the regulation of cellular behavior. A challenge that remains to be studied is the role of the extracellular matrix in the transition from normal physiology to a cancerous niche. The matrix of the basement membrane and interstitium is made up of fibrous proteins, glycoproteins, proteoglycans, and polysaccharides. Proteoglycans are one of the three most abundantly found molecules in the extracellular matrix. These proteoglycans interact with soluble factors such as chemokines, cytokines, growth factors, and other matrix macromolecules, thereby playing an important role in cell interactions with the matrix. Biomimetic proteoglycans that mimic natural proteoglycan structure were synthesized in the Drexel Biomaterials Laboratory and consisted of a biologically inert polyacrylic acid (PAA) core and natural chondroitin sulfate bristles. This novel macromolecule was used to determine the influence of matrix chondroitin sulfate proteoglycans found in tumor microenvironments on interstitial flow-induced invasion through an in vitro 3D invasion assay. Characterization of the in vitro environment was done to quantify changes in matrix permeability, as well as qualitatively assess structural and morphological changes of the collagen fiber network and melanoma cells. We proposed that the presence of these biomimetic chondroitin sulfate proteoglycans (with PAA core molecular weights of 10 and 250 kDa) would decrease the permeability of the matrix and lead to greater flow-induced invasion of melanoma cells due to growth factor binding to the chondroitin sulfate side chains, thereby promoting formation of a chemokine gradient. Lower concentrations of biomimetic proteoglycans increased matrix permeability and dramatically altered collagen fiber matrix structure; however, there was no effect on invasion of melanoma cells. High concentrations ([greater than or equal to]20mg/ml) of biomimetic proteoglycans had no effect on collagen matrix permeability, but the 250 kDa core proteoglycan increased flow-induced invasion compared to the 10 kDa core proteoglycan. The significant differences in matrix structure may be the cause of the increase in permeability when biomimetic proteoglycans were present in the matrices. The difference in flow-induced invasion between the two sizes of biomimetic proteoglycans led us to hypothesize that the size of the proteoglycan and the degree of chondroitin sulfate decoration impacts invasive characteristics of melanoma cells through growth factor binding. These studies have advanced the possibility of using these biomimetic proteoglycans to generate more defined in vitro matrix microenvironments. Moving forward, using biomimetic proteoglycans to better mimic the tumor microenvironment can help determine how a multitude of factors influence cellular behavior and disease progression.
A New Formulation and Uniqueness of Solutions to A. Horns Problem
Authors:   , Cao Lei , Woerdeman Hugo J.
Published: July 2021

This Ph. D thesis concerns A. Horns problem characterizing those triples ( ; ; ) forwhich there exist Hermitian matrices A;B;C with eigenvalues ; and respectively,satisfyingA + B = C:We will provide a new formulation of solutions to A. Horns problem by whichone can verify if a triple ( ; ; ) is a solution to A. Horns problem without the recursiveprocess to derive all Horns inequalities. Moreover, an extended result to thequestion what is the set of all possible eigenvalues of the sum of Hermitian matricesA1;A2; : : : ;An which have eigenvalues 1; 2; : : : ; n respectively is included. We alsostudy the question when the solution matrices A;B and C are unique up to simultaneousunitary similarity. This problem was solved by Knutson and Tao througha heavy algebraic geometry machine and we will prove two special cases by linearalgebra techniques. In addition, we will provide a more detailed proof for the case ; and lie in Qn+: We prove that uniqueness occurs exactly when there exists aunique hive with border ( ; ; ): When ; and are partitions, this means thatuniqueness occurs exactly when the Littlewood-Richardson coefficient C equals 1.
Chiral and Achiral Copper(II) and Nickel(II) Complexes with Novel Multidentate Ligands
Authors:   , O'Connor Molly A. , Addison Anthony William
Published: July 2021

Bidentate, tetradentate, and hexadentate ligands, with N₂, N₄, and S₂N₄ donor sets were complexed with Cu(II) and Ni(II) to form chiral and achiral chelates in an attempt to prepare complexes that allowed for the access of multiple oxidation states through electrochemical methods. The bidentate ligands were prepared from pyrrole-2-carboxaldehyde and chiral and achiral amines and anilines, and were complexed with the desired metal in a 2:1 ratio, with chiral ligands resulting in chiral complexes. Analogous ligands with N₄ coordination spheres were also prepared using pyrrole-2-carboxaldyhyde and various diamines, and were complexed in a 1:1 fashion. The tetradentate ligands were prepared using vinylpyridine and chiral piperazine derivatives to form both enantiomers of the chiral complexes, as well as similar non-chiral mono and dinuclear complexes using achiral derivatives of piperazine and homopiperazine. The hexadentate ligands were synthesized from 2-hydrazinopyridine and alkyl and aryl bridged dithio-diketo precursors, which were prepared using either a N,N,N-triethyl-N-(propan-2-onyl)ammonium or N,N,N-triethyl-N-(phenylethan-2-onyl)ammonium chloride salt and a range of dithiols. Synthetic, crystallographic, and absorption data will be presented as well as circular dichroism (CD) data for the chiral complexes and magnetic data for the dinuclear complex. Complexes were also characterized using electrochemistry and ESR.
The Effects of Bulkheading on Diamondback Terrapin Nesting in Barnegat Bay, New Jersey
Authors:   , Winters Julianne Marie , Avery Harold W.
Published: July 2021

As human populations continue to increase, costal development severely depletes the natural resources of Americas estuaries. Barnegat Bay, New Jersey shows the highest rate of shoreline development of any mid-Atlantic estuary in the past 30 years. Hard erosion control walls, called bulkheading cover 45% of Barnegat Bay, impeding nesting diamondback terrapins (Malacleymys terrapin) from reaching high dune habitat. This dissertations objective is to determine how diamondback terrapins behaviorally and physiologically respond to bulkheading and related anthropogenic activities while nesting. By monitoring two nesting beaches within Barnegat Bay, Conklin and Sedge Islands, I quantified the probability of terrapin nesting emergence simultaneous to environmental and anthropogenic factors. There was no significant effect of motorized boats, personal watercrafts, kayaks, or human presence on terrapin emergence. Instead, terrapins responded to environmental cues such as water (26 °C) and air (27.5° C) temperatures, time of day (13:30), and tidal stage (outgoing). To determine the effects of bulkheading on nesting terrapin movements I utilized biotelemetry to measure terrestrial and aquatic habitat use at artificial bulkheading. Terrapins showed variable, site-specific responses to bulkheading. At Conklin Island, terrapins encountering bulkheading travelled significantly further with more tortuous paths on land than females nesting at unobstructed beaches. At Sedge Island, however, terrapins spent significantly more time in the water at bulkheading instead of travelling more on land. I measured corticosterone (CORT) and testosterone (T) secretion levels to determine the stress response in reproductive females from bulkheading. After handling, terrapin profiles of acute CORT increased significantly, approaching peak levels of 8 ng/ml. There were no significant increases in CORT or T due to bulkheading, however, indicating that barriers do not cause nesting terrapin stress. Over the reproductive season, T dropped significantly while CORT levels were maintained. My results suggest that diamondback terrapins lack behavioral and physiological responses to anthropogenic stressors at nesting beaches. To conserve shorelines for terrapins and other estuarine wildlife, sustainable development, accessible enhanced artificial nesting habitats, and human beach closures must be implemented. With the high rate of bulkheading construction in Barnegat Bay and nation-wide, this research provides a novel approach to managing human-wildlife conflicts within Americas estuaries.
Development and Characterization of UHMWPE Fiber-Reinforced Hydrogels For Meniscal Replacement
Authors:   , Holloway Julianne Leigh , Lowman Anthony M. , Palmese Giuseppe R.
Published: July 2021

Meniscal tears are the most common orthopedic injuries to the human body. The current treatment of choice, however, is a partial meniscectomy that leads to osteoarthritis proportional to the amount of tissue removed. As a result, there is a significant clinical need to develop materials capable of restoring the biomechanical contact stress distribution to the knee after meniscectomy and preventing the onset of osteoarthritis. In this work, a fiber-reinforced hydrogel-based synthetic meniscus was developed that allows for tailoring of the mechanical properties and molding of the implant to match the size, shape, and property distribution of the native tissue. Physically cross-linked poly(vinyl alcohol) (PVA) hydrogels were reinforced with ultra-high molecular weight polyethylene (UHMWPE) fibers and characterized in compression (0.1 - 0.8 MPa) and tension (0.1 - 250 MPa) showing fine control over mechanical properties within the range of the human meniscus. Morphology and crystallinity analysis of PVA hydrogels showed increases in crystallinity and PVA densification, or phase separation, with freeze-thaw cycles. A comparison of freeze-thawed and aged, physically cross-linked hydrogels provided insight on both crystallinity and phase separation as mechanisms for PVA gelation. Results indicated both mechanisms independently contributed to hydrogel modulus for freeze-thawed hydrogels. In vitro swelling studies were performed using osmotic solutions to replicate the swelling pressure present in the knee. Minimal swelling was observed for hydrogels with a PVA concentration of 30-35 wt%, independently of hydrogel freeze-thaw cycles. This allows for independent tailoring of hydrogel modulus and pore structure using freeze-thaw cycles and swelling behavior using polymer concentration to match a wide range of properties needed for various soft tissue applications. The UHMWPE-PVA interface was identified as a significant weakness. To improve interfacial adhesion, a novel biocompatible PVA grafting technique was developed to form a direct covalent linkage at the fiber-matrix interface. Chemical grafting was tailored as a function of the number of sites available for covalent bonding and the percentage of sites reacted. PVA grafting resulted in significant improvements to interfacial shear strength from 11 kPa without any treatment to above 220 kPa following grafting. After grafting, failure was observed cohesively within the PVA hydrogel indicating the UHMWPE-PVA interface was successfully optimized. Lastly, in vitro gait simulations and an in vivo sheep study demonstrated the feasibility and biocompatibility of the proposed UHMWPE-PVA composite. The results from this work can be applied to designing materials for other soft tissue applications, including the anterior cruciate ligament (ACL) and the annulus fibrosus.
Novel Cantilever Sensor for Antibody-based and hlyA gene-based Sensitive Detection of Foodborne Pathogen
Authors:   , Sharma Harsh Pradipkumar , Mutharasan Rajakkannu
Published: July 2021

The objectives of this research can be broadly categorized as: 1) Cantilever sensor design and characteristics, 2) Improved surface chemistry for immobilization of recognition molecules and 3) Sensing of contaminants in food and cell-culture matrix. A novel asymmetrically anchored piezoelectric millimeter-sized cantilever (aPEMC) design was developed. The new cantilever design is simpler and has lesser fabrication variables that improved the reproducibility of these devices. The sensor design was corroborated and characterized using finite element modeling and these were shown to be highly sensitive (~1 fg/Hz) via molecular chemisorption studies. The importance of the binding strength between the sensor and the added mass was shown to govern the type of resonance frequency change exhibited by the cantilever sensors and the high-order resonance oscillation modes were characterized by comparing responses to that quartz crystal microbalance (QCM) and finite element modeling. A novel and dry method for grafting reactive amine groups on polyurethane surfaces using pulsed-plasma generation of ammonia gas was demonstrated. Grafting of amine groups was corroborated by FTIR studies and SEM micrographs in addition to the cantilever sensor responses to protein immobilization. A method using tris(2-carboxyethyl)phosphine (TCEP) to reduce the disulfide bridges in antibody molecules, without affecting the antigen binding activity, to expose their native thiol groups for immobilization of gold surfaces was developed. The half antibody fragments were shown to improve the detection sensitivity of QCM biosensors without loss of selectivity. Piezoelectric millimeter-sized cantilever (PEMC) sensors were used to demonstrate detection of cell-culture mycoplasmas in buffer and cell-culture matrix at 103 CFU/mL. The detection responses were confirmed by using a second antibody binding step, much like ELISA sandwich format. aPEMC sensors were used to show detection of foodborne pathogen, Listeria monocytogenes (LM), in buffer and milk at concentration of 103/mL. The detection sensitivity was limited by commercially available low-avidity antibody. The single copy, virulence hlyA gene of LM was used to design a DNA probe that was used to detect genomic DNA extracted from LM in the presence of ~104 times higher non-target genomic DNA. Detection of genomic DNA equivalent to 7x102 LM was achieved within ~90 min.
Analysts' Incentives and Usage of Valuation Models
Authors:   , Hua Shaowen , Werner Edward , Curatola Anthony Paul
Published: July 2021

This dissertation explores how analysts' underwriting and trading incentives direct their use of valuation methods to generate stock recommendations. Using brokerage firm-level underwriting and trading data from 1998 to 2011, I find that analysts' underwriting incentives contribute to conflicting research outputs generated through both residual income models and simple heuristic models. I also find that trading incentives reduce conflicting messages obtained using residual income models, but not those generated by simple heuristic models. My study expands our knowledge of analysts' valuation process by documenting how underwriting and trading incentives affect the transformation of earnings forecasts into stock recommendations.
A Sequential Mixed Methods Study
Authors:   , Johnson Brian , Grant Allen C.
Published: July 2021

Emotional intelligence is a relatively new academic discipline that began forming in the early 1990s. Currently, emotional intelligence is used in academia and in business as a new intelligence quotient. This research study investigates how Senior Student Affairs Officers' use their emotional intelligence ability during critical incidents. The study explored the emotional intelligence of Senior Student Affairs Officers by examining the critical area of managing emotions. Additionally, the study used each participant's emotional intelligence data to understand and provide meaning to how Senior Student Affairs Officers manage critical incidents using their identified emotional intelligence capabilities. A sequential mixed methods exploratory research design was used as the framework for this research. The quantitative aspect of the study used the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) to establish a baseline set of data regarding Senior Student Affairs Officers' capabilities for managing emotions. The quantitative data were gathered through in-person interviews conducted with three Senior Student Affairs Officers at their place of employment. The MSCEIT assessment findings indicate that the sample population exhibited a competent rating in their ability to manage their emotions. The interviews further explored the concept of managing emotions through the lens of critical incidents that occur on campus. Findings from the sample population of Senior Student Affairs Officers indicated that they have a competent rating for their ability to manage their emotions. Scoring for the competent rating resulted from a comparison of the normative database for the MSCEIT test. In addition, the results indicated that age, gender, education level, and years of experience of the sample population did not statistically impact the participants ability to manage their emotions. Finally, the qualitative aspect of the study deeply revealed how the sample senior student affairs officers manage their emotions in practice.
Choose-your-own subscriptions
Authors:   , Dragga Nicholas , Brody Jean
Published: July 2021

It is the purpose of this study to determine what successes - or not -organizations are experiencing with the "choose your own" (CYO) subscription model. Individual orchestras were asked to share their experience and data on CYO subscription plans. Unfortunately, lacking quantitative data made a definitive argument on the CYO model difficult. However, participating orchestras had remarkably similar anecdotal experiences, so apparent trends are identified for future study: (1) the CYO purchaser is a unique demographic, (2) organizations should develop CYO specific campaigns, and not waste resources marketing full season offers to CYO potentials, (3) upgrading any single ticket purchaser to a CYO is a positive transition. Since the above three theories, if proved consistent, could have a significant impact on orchestra ticketing strategies, organizations who devote the resources necessary to track CYO sales and the CYO audience, may be better equipped to engage the next generation of arts patrons.
Punchdrunk
Authors:   , Keegan Laura M. , Brody Jean
Published: July 2021

This case study investigates the growth and development of Punchdrunk, a United Kingdom (U. K.) based Theater Company. Punchdrunk's dedication to its aesthetic and brand, combined with dual leadership, creative marketing and inventive partnerships have positioned the organization to reach large audiences and remain nimble in an unstable sector. This paper finds that this organization has risen to the challenge of maintaining artistic integrity and remaining sustainable, challenges which are faced by all nonprofit arts organizations. The combination of traditional funding mechanisms, alternative revenues, creative partnerships and corporate sponsorship enable Punchdrunk to continue to pursue their ambitious mission: to transform the passive consumption of the arts into life changing experiences for everyone.
Purpose of social media in the American orchestral field
Authors:   , Szychulski Audrey , Brody Jean
Published: July 2021

The purpose of this paper is to define what is presently happening among practitioners in the American orchestral field within the subject of social media. While Web 2.0 applications have gained various uses in arts marketing, researchers are still determining functions and factors for success. This study discusses changing strategies of marketing and public relations due in part to the influences of Web 2.0 applications. A survey and analysis of whom American orchestras are, what they are presently doing, and their desired results are included. Results are then applied to what are considered best practices in social media to make recommendations for activities that American orchestras could be. The anticipated outcome of this study is a better understanding of how and why American orchestras are using social media.
A case study in rightsizing a small arts organization's building
Authors:   , Knisely-Merritt Sarah , Brody Jean
Published: July 2021

For a decade, from the 1990s to early 2000s, the arts sector in this country experienced an unprecedented building boom. Organizations of every size and structure were a part of what is now referred to as the great cultural building boom. The economic crisis of recent years was the downfall of many of these building projects, forcing organizations to rethink the importance of facility as it relates to artistic programming. This thesis explores the issues facing the Arts Council of Wayne County, a small, rural arts council in eastern North Carolina. Through research and the experiences of the organization's Executive Director, Sarah Merritt (the author), the process of rightsizing the ACWC's facility and its resulting effect on its programs are examined.
Mindful Leadership
Authors:   , Bach Phe Xuan , Bureau W. Edward
Published: July 2021

The lack of a spiritual dimension (moral and ethical) in leadership, which frames the development of moral value-from business and politics to family and education-has become a key factor contributing to negative consequences caused by unethical leaders. Both Eastern and Western society also lack an in-depth understanding of how the spiritual leadership practices of Vietnamese Buddhist monks might/may be models of moral and ethical leadership for others in the larger society. This qualitative research study utilizes a phenomenological approach to learn how to apply the leadership lessons derived from the lived experience of Vietnamese Buddhist monks in contemporary America. The study is composed of historical and contemporary literature, empirical research on relevant leadership theories, on Buddhist values (especially those of mindfulness and compassion as part of their daily routine). In order to have a peaceful way of life, to help and lead others, Vietnamese monks learn from their masters, practice their learned core values and utilize Zen practices. The researcher interviewed 14 Buddhist monks across United States of America by snowball effect sampling and the three main themes emerging from the research are as follows: (a) Vietnamese Buddhist monks in America and their lived-experiences are dynamic, unique and contributing to the society within their spiritual leadership roles and obligations; (b) Their leadership style is characterized as authentically leading by example by basing decisions upon the core values of mindfulness, compassion, and wisdom; and (c) Through their practices, their presence, and their contributions to the welfare of others, they bring about peace of mind and happiness for themselves and for others in society. The findings were extracted from participants, resulting in the five principles of a mindful leadership. The five leadership strategies discussed include: Leading from the Inside Out, the Notion of Daily Practice, Leading-by-Example, Congruence, and the Notion of Completeness. Eleven recommendations emerged from this phenomenological study with eight being the techniques and strategies to achieve mindfulness, peace, compassion, and happiness and the remaining three being dedicated for further studies. Keywords: Buddhism, Buddhist, Buddhist values, compassion, Dharma, leadership practices, leadership styles, leadership theories, meditation, mindful leadership, mindfulness, phenomenological study, phenomenology, spiritual leadership, Vietnamese Buddhism, Vietnamese Buddhist monks, wisdom, Zen practices, Zen.
Coping with bereavement through the use of optimistic emotional disclosure
Authors:   , Gilrain Kelly Lynn , Kloss Jacqueline D.
Published: July 2021

Recent bereavement research has attempted to identify appropriate and beneficial interventions for those experiencing the painful mental and physical sequelae following the loss of a loved one. According to Fredrickson's (1998) "broaden and build" theory, the lasting effects of positive emotions can transform people into more creative, resilient and healthy individuals. Using writing as a tool for emotional disclosure, this study compares those who are directed to write about their loss (ED), those who are directed to write about their positive beliefs, hopes for the future, and character-building aspects of experiencing the loss (P), and those who write about neutral events as a control (N). Results indicate that while all groups decrease in negative affect over time F (5, 55) = 4.8, p<.01, the P group significantly increased their ability to "actively cope" with their loss from baseline to a 6-week follow-up, t (2, 19) = -2.2, p<.05. However, the P group also reported less "Acceptance" of the death at a 6-week follow-up when compared to their baseline level of acceptance, t (2, 19) = 3.52, p<.01. Individuals in the ED group report less "active coping" at a 6-week follow-up when compared to their baseline level of active coping, t(2, 20) = 2.73, p = .01. Interestingly, individuals in the ED group did not write solely about their negative emotions related to the death and instead wrote primarily from a positive perspective during each session. To examine this phenomenon further, future research should explore the role of positive and negative emotion within the context of traumatic loss.
One-Step Crosslinking and Functionalization of Electrospun Fibers
Authors:   , Buck Emily Christina , Schauer Caroline L.
Published: July 2021

One-step crosslinking of electrospun poly(allylamine) fibers was investigated for two new crosslinking agents: hexamethylene-1,6-diamino(carboxysulfonate) (HDACS) and genipin. Electrospun fibers have high surface area to volume ratios and high porosity, making them excellent candidates for water filtration membranes. Poly(allylamine) fibers were electrospun from acidic solvents to prevent crosslinking during the electrospinning process. As-spun poly(allylamine) fibers had an average diameter of 405±246 nm, while poly(allylamine) fibers containing HDACS and genipin had average fiber diameters of 879±272, and 538±269 nm, respectively. Activation of HDACS and genipin within the poly(allylamine) fibers initiated covalent crosslinking that allowed the crosslinked fibers, which was confirmed through FTIR spectroscopy and solubility testing in aqueous environments of pH 3, 7, and 13. The activated poly(allylamine) fibers crosslinked with HDACS and genipin remained stable in aqueous environments of pH 3, 7 and 13 up to 72 h, while the control fibers dissolved in pH 3 and 7 by 72 h. Additionally, a procedure for thiol-modification of one-step crosslinked electrospun chitosan fibers was developed. One-step electrospun chitosan fibers were crosslinked with glutaraldehyde in order to retain the stability of chitosan in aqueous environments. Glutaraldehyde also served as the reaction site for covalently attaching the thiol-containing molecule, L-cysteine, to the chitosan fibers. EDS confirmed the presence of sulfur and Ellman's reagent testing showed that sulfur exists in the form of thiol groups on the thiol-modified chitosan surface. Finally, FTIR confirmed the covalent attachment of L-cysteine to the crosslinked chitosan fibers. Since both poly(allylamine) and thiol-modified chitosan have intrinsic metal chelation properties, electrospun poly(allylamine) and thiol-modified chitosan fibers show great promise for removing heavy metal ions from contaminated water.
Load Flow Analysis of Multi-Converter Transmission Systems
Authors:   , Cruz Shaun Mendoza , Nwankpa Chikaodinaka Okechi Dike
Published: July 2021

This thesis discusses the development of a load flow methodology capable of solving for the load flow of power systems inclusive of multiple point-to-point HVDC links. The methodology is an extension of a previous algorithm developed by Sato and Arillaga. Recent pushes for renewable power and developments supporting HVDC transmission for short distances will facilitate the substitution of multiple HVDC links for existing transmission lines. The extended methodology is utilized as a load flow analysis tool and is applied to various power systems to determine the effects of multiple HVDC links on the convergence properties of the load flow methods (i.e. timing and number of iterations). It was found that the percentage of DC transmission in a system is a good indicator of which embedded AC load flow method should be utilized in the extended methodology. Specifically at a DC transmission percentage of 90% or higher, the Gauss Seidel method has speeds comparable to the Newton-Raphson method. Leveraging off this finding, an Enhanced Load Flow solver is developed, which optimizes for faster convergence with a second priority to reducing memory requirements. The Enhanced Load Flow solver is a robust methodology which is easily extended to include other AC load flow methods. This research also looked into the effects of substituting AC transmission lines with HVDC links on the speed of convergence for voltage stability studies. It was found that the substitution of HVDC links for lines connected to a heavily loaded bus for a stressed system yields a lower convergence time for the voltage stability study.
Fabrication and Characterization of Poly(4-vinylpyridine)-Based All Solid State Dye-Sensitized Solar Cells by Initiated Chemical Vapor Deposition
Authors:   , Farrell Steven L. , Lau Kenneth K. S.
Published: July 2021

The novel technique of initiated chemical vapor deposition (iCVD) was used to develop an all solid state dye-sensitized solar cell (DSSC) using a solid polymer electrolyte. iCVD was chosen for this process due to its advantage in polymerizing within high aspect ratio porous geometries. Poly(4-vinylpyridine) (P4VP) was synthesized via iCVD in a planar geometry on a silicon wafer to observe the effects of iCVD reaction conditions on the deposition rate and properties of the resulting thin film. P4VP-based DSSCs were fabricated in iCVD using previously described methods for other polymers. Using N-719 ruthenium dye, the DSSCs were fabricated and tested with linear sweep voltammetry. The results were compared to liquid-based DSSCs prepared using similar materials and methods without iCVD treatment. The deposition rate of iCVD has been found to have a positive, linear relationship to the ratio of monomer pressure to saturation pressure (PMono/PSat). This change is independent of how the reaction conditions were varied, as changes in pressure and temperature carried the same effect on deposition rate. The P4VP-based cells exhibited efficiencies up to 1.5% compared to the liquid-based cell efficiencies up to 3.1%, however the polymer cells had a fill factor that was up to 10% greater than that of the liquid cells. The average short-circuit current density for the P4VP-based cells was 4.14 ± 0.35 mA/cm2 compared to the liquid cell average of 10.42 ± 0.19 mA/cm2. The average open-circuit voltage for the P4VP-based cells was 0.516 ± 0.005 V compared to the liquid cell average of 0.490 ± 0.003 V.
Logical Reasoning Deficits and Severity of Delusional Symptomatology in Psychotic Disorders
Authors:   , Gallagher Colin J. , Williams J. Michael
Published: July 2021

Research in psychotic disorders has recently been focused on identifying early indicators of future symptomatology. Our study aimed to establish a model for the relationship of a test of logical reasoning, moderated by belief inflexibility, for predicting delusional symptomatology. As part of the Neurodevelopment in Adolescence and Young Adulthood (NAYA) study, the Penn Computerized Neurocognitive Battery (CNB) was administered to three groups: individuals with a psychotic disorder (PD) (N = 17), individuals at high-risk for a psychotic disorder (HR) (N = 26), and individuals at lowrisk for a psychotic disorder (LR) (N = 19). The Penn Conditional Exclusion Task(PCET) was specifically examined through the use of its measures of accuracy and perseverative errors to see its predictive ability for delusional symptomatology as measured by the Scale for the Assessment of Positive Symptoms (SAPS) and the Scale of Prodromal Symptoms (SOPS) Positive Symptoms Subscale. Results indicated small to large effect sizes for group differences on PCET outcome variables, and evidence of a moderation relationship was also found for the PD and HR group tests. Possible implications of these findings are that the PCET can be used to predict the course of delusional symptomatology. The development of a psychotic symptoms scale that takes into account the range of symptoms from the prodromal to post-onset stages is necessary to accurately test such possible predictor models.
Mock Jurors' Perceptions of Experts
Authors:   , Galloway Meghann , Williams J. Michael
Published: July 2021

Although expert psychological testimony it is not present in every trial, it has the potential to greatly influence the outcome of trials when it is used. As such, it is important to understand factors that influence how jurors receive psychological testimony. Yet before expert testimony is presented, an attorney must hire the expert. This process of selection requires further scrutiny, as it is possible that persuasive and qualified experts never make it before a jury. Gender is a factor that has the potential to bias both jurors and attorneys despite being unrelated to expert qualifications. This study examined whether expert sex impacts juror and lawyer perceptions of expert credibility, as well as whether this perceived credibility is impacted by the gendered nature of the crime in question. It was hypothesized that lawyers who found experts more credible, or believe the jury will perceive them as more credible, would be more likely to use them. It was further presumed that jurors who believe an expert to be more credible might be more persuaded by the expert's testimony. Results indicated that the most salient characteristic presented in the case vignettes was neither the expert sex nor the gender of the defendant, but rather the circumstances of the crime committed. There was some indication the gendered nature of the crime interacted with the gender of the defendant to influence expert credibility, but this effect was independent of the expert's sex.
Varying the Porosity of Electrospun Monoaxial and Coaxial Collagen Nanofibers
Authors:   , Gifford-Hollingsworth Ryan Christopher , Schauer Caroline L.
Published: July 2021

As the average age in the United States increases, so do the costs associated with a variety of chronic conditions, which when symptom management is applied can lead to drug tolerance and the onset of side effects over long term drug exposure. Personalized medicine is an area of research, which proposes to manage symptoms and/or treat disorders without long term tolerance or side effects. Electrospinning is a rapid, cost effective technique, which can be utilized to generate non-woven, nanofibrous matrices that resemble the body's own extra cellular matrix (ECM). The ability for these mats to resemble the natural ECM leads to high levels of cell adhesion, growth, proliferation and differentiation. The unique capabilities of electrospun matrices were investigated here by applying the technique to generate: matrices of gelatin and collagen with varying salt concentrations and matrices containing the glycosaminoglycan (GAG) chondroitin sulfate (ChS). The gelatin and collagen matrices were analyzed for their ability to trap salts both within the matrix and within the individual fibers. The matrices were subsequently leached to form pores. The mats were analyzed using FESEM, FTIR and EDS to determine the presence and release of salt. It was shown that the salt entrapment could be controlled by controlling the solution salt concentration and that, after covalently crosslinking the fibers, the salts could be leached while maintaining some of the fibrous structure. The ChS containing matrices were analyzed to determine the effect of blend polymer net charge on the fiber forming capacity of the polymer blend solutions. The mats were analyzed with FESEM, FTIR and EDS to determine the presence of the various blend polymers and ChS. It was found that the molar ratio of ChS:blend polymer in solution played a large role in the concentration of ChS in the final fibrous matrices. Also, it was found that electrospinning another GAG, hyaluronic acid (HA), with ChS led to the highest concentration of ChS in the fibrous matrices. These mats will be further investigated for applications in regenerating cartilaginous tissue for articulating joint repair.
The design of a novel 3D micropatterned tumor microenvironment model to study the intercellular effects of fibroblasts and cancer cells
Authors:   , Ho Christine Maylin , Shieh Adrian C.
Published: July 2021

The tumor microenvironment contains a multitude of biomolecules, stromal cells such as fibroblasts, endothelial cells, inflammatory cells, and signaling molecules that support the tumor's growth and progression. Particularly around the site of tumors, fibroblasts are "primed" to adopt a myofibroblastic phenotype, and are known as cancer associated fibroblasts (CAFs) that promote tumor growth and progression instead of aiding the body. Much interest has been taken in the individual cellular interactions between tumor cells and the surrounding cancer-associated fibroblasts. Systems are constantly being designed to better emulate the complex internal environment around the tumor in order to understand how the tumor stroma communicates and affects the tumor growth. In this thesis, a 3D microenvironment model was developed that simulates the native extracellular matrix and allows for the study of individual cellular interactions between cancer cells and fibroblasts, particularly those involving transmission of cell-generated contractile forces. The final system design in brief involves spatially constraining MDA-MB-231 human breast adenocarcinoma cells and human dermal fibroblasts on fibronectin micropatterns on a polydimethylsiloxane (PDMS) substrate. A poly-L-lysine/glutaraldehyde treated PDMS gasket was placed around the cells, and a collagen overlay was added, to allow cells to interact with a 3D environment. Live cell microscopy was used to track cell movement over time, and the images were analyzed with MATLAB. Additionally, a protocol for differentiating myofibroblasts was optimized for the inclusion into the system. The significance of this study is that it offers a novel 3D cell culture system that boasts of the ability for control over individual cell positions in order to observe the effects of fibroblasts and cancer cells in a 3D environment that resembles the in vivo environment more than that of the standard 2D culture system.
A Mixed-Methods Analysis of Iraqi Refugees with Potential Trauma Histories
Authors:   , Ibrahim Arwa Y. , Herbert James D.
Published: July 2021

Posttraumatic Stress Disorder (PTSD) is the dominant paradigm for understanding reactions to traumatic events. The majority of individuals exposed to traumatic events do not develop long-term pathological responses. However, refugees are believed to be especially vulnerable due to increased exposure to traumatic events in premigration combined with transitional and resettlement stress. Extant research has thus far provided inconclusive results regarding long-term psychopathological risk. Moreover, studies that indicate high rates of PTSD in refugees should be interpreted with caution given that most studies assume the positivistic position that PTSD is a universal disorder and thereby adopt etic-only methodological approaches that carry important limitations. Findings from a small body of culturally-sensitive behavioral research that adopts combined emic-etic methods suggest that PTSD may not be the most relevant framework for understanding reactions to traumatic stressors in some cultures, and in fact that exposure to PTSD discourse may even increase the likelihood of having the disorder. This study adopted a combined emic-etic approach to explore responses to potentially traumatic events in an understudied population, Iraqi refugees. It was hypothesized that the relative rate of PTSD in this sample would be lower than other psychiatric symptoms, and familiarity with Western trauma discourse rather than exposure to traumatic events would be associated with PTSD. Participants were recruited in the United States (n = 19) through chain referral convenience sampling, and completed a culturally-sensitive and linguistically-specific semi-structured interview followed by self-report measures administered in person or electronically. The sample experienced a high number of "criterion [beta][omega]A" traumatic events, but the majority did not meet criteria for any psychiatric disorder assessed. The prevalence of PTSD exceeded the US civilian past year prevalence rate but the number of clinically symptomatic cases, as well as the severity of symptoms, was significantly greater for mood and anxiety symptoms than for PTSD. Familiarity with Western trauma discourse and acculturation were positively associated with a diagnosis of PTSD but largely not associated with non-PTSD symptoms and diagnoses. There was no association between Criterion A events and PTSD. The findings challenge the dominant paradigm by suggesting that PTSD in its current formulation may not best describe reactions to traumatic stressors in Iraqi refugees. The results also support the theory that the onset and maintenance of PTSD may be due in part to suggestibility. The willingness of participants to be so open about psychiatric symptoms underscores the importance of using culturally-sensitive methods in such investigations.
Animating ancient ontogeny
Authors:   , Newman Daniel Joel , Rank Stefan , Mauriello David A. , Daeschler Edward
Published: July 2021

This thesis seeks to design an Integrated Interpretive Visualization (I2V) with the broader goal of making fossil collections and the important biology surrounding them more visible and accessible to the public. The public are twice separated from the significance of paleontological specimens. First, there is the geological time that separates one from the original context of a fossil, that being a living organism. Second, there is an accessibility gap between the public and the collections that store fossils. Direct access to original source fossils is often limited. I2V can be leveraged to unite the public with fossil collections, the connections between related fossils, and the important theories associated with them. One of these growing topics in paleontology is the evidence of ontogeny or development in the fossil record. I carried out a digital paleontological restoration of a collection of fossils from the Academy of Natural Sciences in Philadelphia. The collection is of the Devonian placoderm Bothriolepis. The collection is significant because it represents compelling evidence of an ontogenic growth series. Using photogrammetry to bring the original fossils into digital space, an ontogenic character rig to interpolate between different life stages, and a web-based layer of annotative content this workflow enables me to present a coherent view of how development might have appeared. This project presents an example for museums and other institutions to mobilize their fossil collections to potentially reach a larger audience with a greater impact.