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Assessment Of The Potential Anti-Tumour Effect Of Salvia Triloba And The Combination Of Salvia Triloba And Paclitaxel On Ovarian Cancer: Skov3 Cell Line, Naela Adel Mohammed

Archived Theses and Dissertations

No abstract provided.

Detecting Hacker Threats: Performance Of Word And Sentence Embedding Models In Identifying Hacker Communications, Susan Mckeever, Brian Keegan, Andrei Quieroz

Conference papers

Abstract—Cyber security is striving to find new forms of protection against hacker attacks. An emerging approach nowadays is the investigation of security-related messages exchanged on deep/dark web and even surface web channels. This approach can be supported by the use of supervised machine learning models and text mining techniques. In our work, we compare a variety of machine learning algorithms, text representations and dimension reduction approaches for the detection accuracies of software-vulnerability-related communications. Given the imbalanced nature of the three public datasets used, we investigate appropriate sampling approaches to boost detection accuracies of our models. In addition, we examine how …

Language-Driven Region Pointer Advancement For Controllable Image Captioning, Annika Lindh, Robert J. Ross, John D. Kelleher

Conference papers

Controllable Image Captioning is a recent sub-field in the multi-modal task of Image Captioning wherein constraints are placed on which regions in an image should be described in the generated natural language caption. This puts a stronger focus on producing more detailed descriptions, and opens the door for more end-user control over results. A vital component of the Controllable Image Captioning architecture is the mechanism that decides the timing of attending to each region through the advancement of a region pointer. In this paper, we propose a novel method for predicting the timing of region pointer advancement by treating the …

Quantum Oscillations From Networked Topological Interfaces In A Weyl Semimetal, I. Lin Liu, Colin Heikes, Taner Yildirim, Chris Eckberg, Tristin Metz, Hyunsoo Kim, Sheng Ran, William D. Ratcliff, Johnpierre Paglione, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Layered transition metal chalcogenides are promising hosts of electronic Weyl nodes and topological superconductivity. MoTe₂ is a striking example that harbors both noncentrosymmetric T_d and centrosymmetric T' phases, both of which have been identified as topologically nontrivial. Applied pressure tunes the structural transition separating these phases to zero temperature, stabilizing a mixed T_d–T' matrix that entails a network of interfaces between the two nontrivial topological phases. Here, we show that this critical pressure range is characterized by distinct coherent quantum oscillations, indicating that the difference in topology between topologically nonvtrivial T_d and T' phases gives …

Tuning Magnetic Confinement Of Spin-Triplet Superconductivity, Wen Chen Lin, Daniel J. Campbell, Sheng Ran, I. Lin Liu, Hyunsoo Kim, Andriy H. Nevidomskyy, David Graf, Nicholas P. Butch, Johnpierre Paglione

Physics Faculty Research & Creative Works

Electrical magnetoresistance and tunnel diode oscillator measurements were performed under external magnetic fields up to 41 T applied along the crystallographic b axis (hard axis) of UTe₂ as a function of temperature and applied pressures up to 18.8 kbar. In this work, we track the field-induced first-order transition between superconducting and magnetic field-polarized phases as a function of applied pressure, showing suppression of the transition with increasing pressure until the demise of superconductivity near 16 kbar and the appearance of a pressure-induced ferromagnetic-like ground state that is distinct from the field-polarized phase and stable at zero field. Together with …

Electrical Identification Of Innate Immune Cells, Rasha Ayman Nasser

Theses

This thesis is concerned with the electrical characterization of the key players of the innate immune cells. Innate immunity is basically the nonspecific immune response that is triggered by any foreign body that attacks the human system. The key players of the innate immune system are mainly dendritic cells and macrophages. Accurately classifying these cell types helps us understand the mechanism of the immune system thereby enabling the development of models to improve new prospects for therapeutics and diagnostics. The characterization described in this thesis is based on extracting the capacitance for each biological cell using I-V curves. The main …

Exploring The Instructional Emergent Writing Strategies Of The Emirati Kindergarteners: A Mixed Method Study, Warda Suliman Al Azri

Theses

This mixed-method study aimed at exploring the nature and the types of instructional emergent writing strategies applied by UAE kindergarten teachers in their classrooms. The study also fathomed the teachers’ views toward the practicality of the instructional emergent writing strategies and the challenges they encountered when teaching emergent writing using these strategies. The study used an exploratory sequential mixed method design. In the first phase of the study, a qualitative mean was used by carrying out semi-structured interviews with a purposive-selected sampling of kindergarten English teachers (n=5). The second phase of the study featured a collection of quantitative data using …

District Promotion Policies For Students With Disabilities: Examining Principal Interpretation And Implementation, Latoya Exum Floyd

Educational Leadership & Workforce Development Theses & Dissertations

The number of students receiving special education services have steadily increased in the United States over the past decade. Students with disabilities (SWD) historically score lower on high stakes tests, and they require considerations beyond academic achievement for promotion. The growing number of SWD and accountability measures included in district promotion policies has resulted in a wide range of principal interpretation of district promotion policies. A principal’s interpretation of district promotion policies affects the district’s high school graduation and dropout rates. Therefore, unclear promotion policies can lead to inconsistent interpretation; which can lead to greater retentions and dropouts for SWD …

Deeply Virtual Compton Scattering At Hall A, Jefferson Lab, Mohamed Nuhman Hashir Rashad

Physics Theses & Dissertations

The Standard Model of particle physics defines quarks and leptons as the basic building blocks of all matter. The interaction between them are mediated by force carrying gauge bosons. Quantum ChromoDynamics (QCD), the theory that explains the strong interaction is still not complete enough to derive the physical observables of a Quark-Gluon system from the fundamental degrees of freedom of it’s constituents. Experimentally observable single particle densities provide important insights into our understanding of the quark-gluon system and hence help fill in the gaps of QCD. Generalized Parton Distributions (GPDs) provide simultaneous information of both spacial and longitudinal momentum distributions …

Wicked Ideas For Wicked Problems: Marine Debris And The Complexity Of Governance, Dawn Helene Driesbach

Graduate Program in International Studies Theses & Dissertations

Myriad challenges regarding earth's common spaces, those unregulated by sovereign state authorities, mount and intensify as resources diminish and competition for commercial, scientific and security advantages increases; the pollution and degradation of those spaces simultaneously expands. Threats to the global commons complicate efforts to achieve international consensus which impedes attempts to develop effective governance. As an example, marine debris is a growing problem and is an existential threat to the global commons.

This dissertation aims to characterize marine debris as a wicked problem and explores the complexity of governance in the global ocean commons by answering two fundamental questions. Under …

Advances In The Understanding Of Sourcing And Fate Of Pyrogenic Organic Matter In The Environment, Aleksandar Ivaylov Goranov

Chemistry & Biochemistry Theses & Dissertations

With higher occurrences of forest fires worldwide, there has been an increase in scientific interest surrounding the chemistry of pyrogenic organic matter (pyOM). The main structural components of pyOM, the condensed aromatic compounds (ConAC), exhibit intriguing physico-chemical properties and have been one of the main focuses of biogeochemical research. The overwhelmingly large number of scientific articles regarding pyOM and ConAC are guided by the assumption that ConAC in the environment are exclusively of pyrogenic origin, even though some recent studies have suggested that some of these ConAC could also be derived from non-pyrogenic radical-driven processes. To evaluate this controversial proposition, …

Disrupting Education: High School Principals’ Efforts To Lead Disruptive Innovation And The Influence Of Isomorphic Mechanisms, Katie Cummings Catania

Educational Leadership & Workforce Development Theses & Dissertations

Students today require skills and dispositions different from those of the past. Despite ongoing efforts to initiate change in schools through reform efforts, little has changed within educational institutions. Current reform efforts do, however, create conditions for principals to lead disruptive innovation within their schools. Research is limited on innovation implementation in education and the various ways isomorphic forces may hinder or contribute to the design and adoption of disruptive innovations. The purpose of this study was to examine how high school principals lead disruptive innovation. Additionally, this study sought to understand how the mechanisms of isomorphism influence the adoption …

The Effects Of Security Framing, Time Pressure, And Brand Familiarity On Risky Mobile Application Downloads, Cody Parker

Psychology Theses & Dissertations

The current study examined the effects of security system framing, time pressure, and brand familiarity on mobile application download behaviors, with an emphasis on risk taking. According to the Prospect Theory, people tend to engage in irrational decision making, and make qualitatively different decisions when information is framed in terms of gains and losses (i.e., the framing effect). Past research has used this framing effect to guide the design of a risk display for mobile applications (apps), with the purpose of communicating the potential risks and minimizing insecure app selections. Time pressure has been shown to influence the framing effect …

Onboard Autonomous Controllability Assessment For Fixed Wing Suavs, Brian Edward Duvall

Mechanical & Aerospace Engineering Theses & Dissertations

Traditionally fixed-wing small Unmanned Arial Vehicles (sUAV) are flown while in direct line of sight with commands from a remote operator. However, this is changing with the increased popularity and ready availability of low-cost flight controllers. Flight controllers provide fixed-wing sUAVs with functions that either minimize or eliminate the need for a remote operator. Since the remote operator is no longer controlling the sUAV, it is impossible to determine if the fixed-wing sUAV has proper control authority. In this work, a controllability detection system was designed, built, and flight-tested using COTS hardware. The method features in-situ measurement and analysis of …

Not Too Hot, Not Too Cold, But Moderately Variable: The Influence Of Environmental Variability On Coral Thermal Tolerance, Courtney Nicole Klepac

Biological Sciences Theses & Dissertations

Anthropogenic climate change is causing an increase in the frequency and severity of marine heat waves, resulting in declining health of coral reef ecosystems worldwide. Coral bleaching events – the breakdown in symbiosis between the coral host and their intracellular photosynthetic algae – are increasingly common in recent years and contribute to widespread losses in coral cover. However, bleaching and heat stress responses vary across spatial scales both within and among coral species. Coral populations native to highly variable environments can have greater bleaching resistance than corals from more stable habitats and corals transplanted into these variable reef sites can …

Secure Answer Book And Automatic Grading, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

In response to the growing need to perform assessments online, we have developed a secure answer book, as well as a tool for automatically grading it for our course on spread- sheet modeling. We applied these techniques to a cohort of about 160 students who took the course last term. In this paper, we describe the design, implementation and the techniques employed to enhance both the security of the answer book and the ease, accuracy and consistency of grading. In addition, we summarize the experience and takeaways, both from the instructor and the student perspectives. Although the answer book and …

Jointly Optimizing Sensing Pipelines For Multimodal Mixed Reality Interaction, Darshana Rathnayake, Ashen De Silva, Dasun Puwakdandawa, Lakmal Meegahapola, Archan Misra, Indika Perera

Research Collection School Of Computing and Information Systems

Natural human interactions for Mixed Reality Applications are overwhelmingly multimodal: humans communicate intent and instructions via a combination of visual, aural and gestural cues. However, supporting low-latency and accurate comprehension of such multimodal instructions (MMI), on resource-constrained wearable devices, remains an open challenge, especially as the state-of-the-art comprehension techniques for each individual modality increasingly utilize complex Deep Neural Network models. We demonstrate the possibility of overcoming the core limitation of latency--vs.--accuracy tradeoff by exploiting cross-modal dependencies -- i.e., by compensating for the inferior performance of one model with an increased accuracy of more complex model of a different modality. We …

Business Practice Of Social Media - Platform And Customer Service Adoption, Shujing Sun, Yang Gao, Huaxia Rui

Research Collection School Of Computing and Information Systems

This paper examines the key drivers in business adoptions of the platform and customer service within the context of social media. We carry out the empirical analyses using the decision trajectories of the international airline industry on Twitter. We find that a firm's decision-making is subject to both peer influence and consumer pressure. Regarding peer influence, we find that the odds of both adoptions increase when the extent of peers' adoption increases. We also identify the distinctive role of consumers. Specifically, before the platform adoption, firms learn about potential consequences from consumer reactions to peers' adoptions. Upon the platform adoption, …

Adelaidecyc At Semeval-2020 Task 12: Ensemble Of Classifiers For Offensive Language Detection In Social Media, Mahen Herath, Thushari Atapattu, Hoang Anh Dung, Christoph Treude, Katrina Falkner

Research Collection School Of Computing and Information Systems

This paper describes the systems our team (AdelaideCyC) has developed for SemEval Task 12 (OffensEval 2020) to detect offensive language in social media. The challenge focuses on three subtasks – offensive language identification (subtask A), offense type identification (subtask B), and offense target identification (subtask C). Our team has participated in all the three subtasks. We have developed machine learning and deep learning-based ensembles of models. We have achieved F1-scores of 0.906, 0.552, and 0.623 in subtask A, B, and C respectively. While our performance scores are promising for subtask A, the results demonstrate that subtask B and C still …

Designing Law To Enable Adaptive Governance Of Modern Wicked Problems, Barbara A. Cosens, J.B. Ruhl, Niko Soininen, Lance Gunderson

Vanderbilt Law Review

In the twenty-first century, our planet is facing a period of rapid and fundamental change resulting from human domination so extensive it is expected to be visible in the geologic record. The accelerating rate of change compounds the global social-ecological challenges already deemed “wicked” due to conflicting goals and scientific uncertainty. Understanding how connected natural and human systems respond to change is essential to understanding the governance required to navigate these modern wicked problems. This Article views change through the lens of complexity and resilience theories to inform the challenges of governance in a world dominated by such massive and …

Optimal Control Of Image Based Visual Servoing (Ibvs) For High Precision Visual Inspection Applications, Mark S. Allen

All Theses

Visual servoing is a control technique that uses image data as feedback in a motion control loop. This technique is useful in tasks that require robots or other automated motion systems to automatically inspect parts or structures in motion. One specific method of visual servoing is Image Based Visual Servoing (IBVS), a method that simply minimizes the differences between an observed image orientation and a desired one. This method works well for orientations where the differences are small, but in the case where the desired orientation is more difficult to reach, the system can become unstable, either driving to infinity …

Utilization Of Kirigami Skins As A Method Of Creating Bespoke Soft Pneumatic Actuators, Steven Michael Iannucci

All Theses

Soft pneumatic actuators have many applications in robotics and adaptive structures. Traditionally, these actuators have been constructed by wrapping layers of reinforcing helical fibers around an elastomeric tube. This approach is versatile and robust, but it suffers from a critical dis-advantage: cumbersome fabrication procedures. Wrapping long helical filaments around a cylindrical tube requires expensive equipment or excessive manual labor.

To address this issue, we propose a new approach towards designing and constructing pneumatic actuators by exploiting the principle of kirigami, the ancient art of paper cutting. More specifically, we use “kirigami skins”—plastic sleeves with carefully arranged slit cuts—to replace the …

Validation Of Novel Obstructive Sleep Apnea Treatment With Silicone Gel Experimental Models, Dustin Walter Burd

UNLV Theses, Dissertations, Professional Papers, and Capstones

Predictive modeling to increase treatment success rates for surgical procedures is becoming more common in the scientific community. For obstructive sleep apnea (OSA), modeling has been predominately performed using computers as opposed to experimental models. Computer simulation saves time by eliminating the need to fabricate complex experimental models but comes at the expense of insight gained through physical observations made in real time. Experimental models for studying OSA are needed to validate computational work, provide perspective on anatomical scale and demonstrate complex deformations in real time. This work addresses prior hurdles in experimental model fabrication with a novel process using …

Light Conditions During Desiccation And Rehydration Impact The Recovery Of Cultured Timmiella Crassinervis, Sotodeh Ebrahimi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many terrestrial mosses of xeric environments experience excess light during extended periods of desiccation. While dry or hydrated, excess light energy can lead to formation of reactive oxygen species and photoinhibition (e.g. damage to Photosystem II) which affects photosynthetic stress and efficiency. This study aimed to determine the effect of duration dry and light intensity (PAR) on cultured shoots of the chaparral moss Timmiella crassinervis, as well as to elucidate the optimal rehydration light conditions for this species. I hypothesized that 1) mosses exposed to higher light intensities during desiccation would incur more damage upon rehydration than those exposed to …

Tectonic Evolution Of The Tucki Mountain Metamorphic Core Complex, Southeastern California: Evidence For Late Cretaceous Extension Within The Sevier-Laramide Orogen, William Killey Barba

UNLV Theses, Dissertations, Professional Papers, and Capstones

The exhumation of Cordilleran metamorphic core complexes from mid-crustal depths in the western U.S. Basin and Range Province has been classically associated with Cenozoic extension. However, recent studies reveal that extensional tectonic exhumation of numerous metamorphic core complexes initiated during the Late Cretaceous. New geologic mapping and structural analysis integrated with geochronology and thermochronology data provide evidence for a Late Cretaceous extensional shear zone, previously interpreted as Miocene in age, within the Tucki Mountain metamorphic core complex on the western flank of Death Valley, California. The shear zone occurs within the immediate footwall of the Miocene-Pliocene Tucki Mountain detachment fault …

A Divide And Conquer With Semi-Global Failover For Software Defined Networks, Kasra Goravanchi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nowadays, many service providers need to provide many other functions than just a network connectivity. They also need to provide network functions such as network address translation, firewall, encryption, Domain Name Service (DNS), caching, routing and many other services. Usually these functions come with the hardware at the user or customer’s premises. This can increase the revenue of the revenue, but also can cost a lot and also be extremely difficult to maintain. Moreover, it is important to be able to configure the network and later modify the configuration to create fault tolerance and to prepare the system for future …

Gardasil Vaccine Trends Within Nevada, California, And The U.S.: A Comparative Study, Karen S. Gutierrez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite decreasing incidence in cervical cancer in the U.S., there continues to be an increase in public health concern for cervical cancer worldwide. Recent studies report that individuals are disproportionately affected based on region, sex, and race. Additionally, the human papillomavirus (HPV) attributable cancers may be reduced between 70% and 90% through the universal use of HPV-vaccines. In order to expand current knowledge and implement intervention programs in Nevada, it is critical to examine the associations among the Gardasil vaccine, cervical cancer screening, and adverse events following immunization as well as to understand the different socio-demographic subgroups affected. To our …

Using The Critical Mathematics Pedagogical Framework To Teach Adult Basic Education Learners: A Transformative Convergent Parallel Mixed Methods Study, Matthew D. Gromlich

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study was to design and implement curricula in the Adult Basic Education classroom that aligned to the Critical Mathematics Pedagogical Framework. Specifically, this study assessed if ABE students’ mathematics anxiety and mathematics self-efficacy ware affected by curricula that aligns to the Critical Mathematics Pedagogical Framework. Using a transformative convergent parallel mixed methods study, this study showed that students taught using CMPF-based lessons specifically reflected on their own attitudes towards mathematics self-efficacy, mathematics anxiety, number positioning, and the need for societal change around mathematical concepts. Both quantitative and qualitative data were analyzed to highlight student reflections and …

Association Between White Matter Hyperintensities, Cortical Thinning, And Clinical Outcomes In Mild Traumatic Brain Injury, Thomas Helmut Knoblauch

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traumatic Brain Injury (TBI) is a global health challenge, with over 4.6 million confirmed cases annually in North America alone. Mild traumatic brain injuries (mTBIs) are the most common and make up approximately 81% of all TBI diagnoses worldwide [1]. Studies indicate that 10–15% of patients suffer from trauma induced symptoms (i.e. headache, loss of balance, cognitive impairments, fatigue, and mental health/affective disorders) as far as 1 year post injury [2]. Prediction and management of these post-traumatic sequalae is complicated by a lack of symptom associated neuroimaging findings. In spite of a “prominent distribution” of frontotemporal WMHs in pediatric subjects …

Fast Neutron Assay Of Elemental Content Of Bulk Samples, Calder Emerson Lane

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research was to analyze the capabilities of fast neutrons in the detection and analysis of various isotopes in bulk samples. The deuterium-tritium (DT) fusion reaction generates highly penetrating, high-energy (14.1-MeV) neutrons which induce nuclear reactions in irradiated targets. Neutrons and gamma rays are generated in these reactions. Emitted gamma rays are characteristic of the emitter; the gamma spectrum enables stoichiometric identification of the assayed samples. Neutron backscattering can also be used for identification of the elemental composition of the sample.

This work had three objectives. The first objective was to develop a computational technique to model …