Digital Commons Network^™

On Some Three-Color Ramsey Numbers For Paths, Janusz Dybizbanski, Tomasz Dzido, Stanislaw Radziszowski

Articles

For graphs G1, G2, G3, the three-color Ramsey number R(G1, G2, G3) is the smallest integer n such that if we arbitrarily color the edges of the complete graph of order n with 3 colors, then it contains a monochromatic copy of Gi in color i, for some 1 ≤ i ≤ 3. First, we prove that the conjectured equality R(C2n, C2n, C2n) = 4n, if true, implies that R(P2n+1, P2n+1, P2n+1) = 4n + 1 for all n ≥ 3. We also obtain two new exact values R(P8, P8, P8) = 14 and R(P9, P9, P9) = 17, furthermore …

Source Separation Approach To Video Quality Prediction In Computer Networks, Ruairí De Fréin

Articles

Time-varying loads introduce errors in the estimated model parameters of service-level predictors in Computer Networks. A load-adjusted modification of a traditional unadjusted service-level predictor is contributed, based on Source Separation (SS). It mitigates these errors and improves service-quality predictions for Video-on-Demand (VoD) by :6 to 2dB.

Computation Of The Ramsey Numbers R(C_4, K_9) And R(C_4, K_10), Stanislaw Radziszowski, Alexander Lange, Ivan Livinsky

Articles

The Ramsey number R(C4, Km) is the smallest n such that any graph on n vertices contains a cycle of length four or an independent set of order m. With the help of computer algorithms we obtain the exact values of the Ramsey numbers R(C4, K9) = 30 and R(C4, K10) = 36. New bounds for the next two open cases are also presented.

The Evaluation And Implementation Of Magnetic Fields For Large Strain Uniaxial And Biaxial Cyclic Testing Of Magnetorheological Elastomers., Dave Gorman, Niall Murphy, Ray Ekins, Stephen Jerrams

Articles

Magnetorheological Elastomers (MREs) are “smart” materials whose physical properties are altered by the application of magnetic fields. In previous studies the properties of MREs have been evaluated under a variety of conditions, however little attention has been paid to the recording and reporting of the magnetic fields used in these tests [1]. Currently there is no standard accepted method for specifying the magnetic field applied during MRE testing. This study presents a detailed map of a magnetic field applied during MRE tests as well as providing the first comparative results for uniaxial and biaxial testing under high strain fatigue test …

Quantification Of Hemodynamic Pulse Wave Velocity Based On A Thick Wall Multi-Layer Model For Blood Vessels, Jeffrey S. Lillie, Alexander S. Liberson, David A. Borkholder

Articles

Pulse wave velocity (PWV) is an important index of arterial hemodynamics, which lays the foundation for continuous, noninvasive blood pressure automated monitoring. The goal of this paper is to examine the accuracy of PWV prediction based on a traditional homogeneous structural model for thin-walled arterial segments. In reality arteries are described as composite heterogeneous hyperelastic structures, where the thickness dimension cannot be considered small compared to the cross section size. In this paper we present a hemodynamic fluid - structure interaction model accounting for the variation of geometry and material properties in a radial direction. The model is suitable to …

Theoretical Modeling Of The Effect Of Polymer Chain Immobilization Rates On Holographic Recording In Photopolymers, Dana Mackey, Paul O'Reilly, Izabela Naydenova

Articles

This paper introduces an improved mathematical model for holographic grating formation in an acrylamide-based photopolymer, which consists of partial differential equations derived from physical laws. The model is based on the two-way diffusion theory of \cite{izabela}, which assumes short polymer chains are free to diffuse, and generalizes a similar model presented in \cite{josab} by introducing an immobilization rate governed by chain growth and cross-linking. Numerical simulations were carried out in order to investigate the behaviour of the photopolymer system for short and long exposures, with particular emphasis on the effect of recording parameters (such as illumination frequency and intensity), as …

Photocatalytic Properties Of G-C3n4–Tio2 Heterojunctions Under Uv And Visible Light Conditions, Rachel Fagan, Declan Mccormack, Steven J. Hinder, Suresh Pillai

Articles

Graphitic carbon nitride (g-C3N4) and titanium dioxide (TiO2) were chosen as a model system to investigate photocatalytic abilities of heterojunction system under UV and visible light conditions. The use of g-C3N4 has been shown to be effective in the reduction in recombination through the interaction between the two interfaces of TiO2 andg-C3N4. A simple method of preparing g-C3N4 through the pyrolysis of melamine was employed, which was then added to undoped TiO2 material to form the g-C3N4–TiO2 system. These materials were then fully characterized by X-ray diffraction (XRD), Brunauer Emmett Teller (BET), and various spectroscopic techniques including Raman, X-ray photoelectron …

Evaluation Of Cytotoxicity Profile And Intracellular Localisation Of Doxorubicin-Loaded Chitosan Nanoparticles, Gabriele Dadalt Souto, Zeineb Farhane, Esen Efeoglu, Alan Casey, Jennifer Mcintyre, Hugh Byrne

Articles

In the emerging field of nanomedicine, targeted delivery of nanoparticle encapsulated active pharmaceutical ingredients (API) is seen as a potential significant development, promising improved pharmacokinetics and reduced side effects. In this context, understanding the cellular uptake of the nanoparticles and subsequent subcellular distribution of the API is of critical importance. Doxorubicin (DOX) was encapsulated within chitosan nanoparticles to investigate its intracellular delivery in A549 cells in vitro. Unloaded (CS-TPP) and doxorubicin-loaded (DOX-CS-TPP) chitosan nanoparticles were characterised for size (473±41 nm), polydispersity index (0.3±0.2), zeta potential (34±4 mV), drug content (76±7 µM) and encapsulation efficiency (95±1%). The cytotoxic response to …

The Evolution Of Strategic Sophistication, Nikolaus Robalino, Arthur Robson

Articles

This paper investigates the evolutionary foundation for our ability to attribute preferences to others, an ability that is central to conventional game theory. We argue here that learning others’ preferences allows individuals to efficiently modify their behavior in strategic environments with a persistent element of novelty. Agents with the ability to learn have a sharp, unambiguous advantage over those who are less sophisticated because the former agents extrapolate to novel circumstances information about opponents’ preferences that was learned previously. This advantage holds even with a suitably small cost to reflect the additional cognitive complexity involved.

Justice Kennedy And The Fisher Revisit: Will The Irrelevant Prove Decisive?, Richard O. Lempert

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Most Court watchers expect Justice Kennedy to cast the deciding vote when the Supreme Court hands down its decision in this term’s installment of Fisher v. University of Texas at Austin or, as it is colloquially titled, Fisher II. What divides observers is not whose vote will be crucial, but the law that vote will make. At one extreme, Justice Kennedy could vote to uphold the Fifth Circuit’s reaffirmation of its earlier decision. When the case was heard, this would almost certainly have meant affirming the circuit court’s decision by an equally divided Court. (Justice Kagan, an almost certain supporter …

Challenges And Opportunities In Dfo-At: A Study Of E-Nable, Jeremiah L. Parry-Hill, Daniel L. Ashbrook

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In this paper, we present the results of a study of the e‑NABLE community–a distributed, collaborative volunteer effort to design and fabricate upper-limb assistive technology devices for distant strangers. We position e‑NABLE as the prototypical example of “Do-it-yourself For Others Assistive Technology” (DFO‑AT) and describe three key findings: how the project does and does not meet the recipient's nuanced needs for functional and social support; how e‑NABLE volunteers' motivations compare to those of volunteers for other efforts, including open source software projects; and we explore the challenges inherent in the distance between volunteers and recipients. We also describe opportunities for …

Novel Mitochondrial Complex I Inhibitors Restore Glucose-Handling Abilities Of High-Fat Fed Mice, Darren Martin, Siobhan Leonard, Robert Devine, Clara Redondo, Gemma Kinsella, Conor Breen, Victoria Mceneaney, Mary Rooney, Tim Munsey, Richard Porter, Asipu Sivaprasadarao, John Stephens, John Findlay

Articles

Metformin is the main drug of choice for treating type 2 diabetes, yet the therapeutic regimens and side effects of the compound are all undesirable and can lead to reduced compliance. The aim of this study was to elucidate the mechanism of action of two novel compounds which improved glucose handling and weight gain in mice on a high-fat diet. Wildtype C57Bl/6 male mice were fed on a high-fat diet and treated with novel, anti-diabetic compounds. Both compounds restored the glucose handling ability of these mice. At a cellular level, these compounds achieve this by inhibiting complex I activity in …

The Welfare Effects Of Nationalization In A Mixed Duopoly Public Transport Market, Feifei Qin, Xiaoning Zhang, Eoin Plant

Articles

Recently, many cities have launched new rail transit lines. Once these new rail transit lines start commercial operation, they will play important roles as competitors to conventional bus services. In this paper, the effects of nationalization on equilibria have been studied in a mixed duopoly public transport market, in which one publicly-owned rail transit operator competes with one private bus operator. Two numerical case studies show the nationalization of a rail transit company is always socially desirable both in Bertrand pricing game in the short run and in Nash non-cooperative game in the long run.

Modification Of The In Vitro Uptake Mechanism And Anti-Oxidant Levels In Hacat Cells And Resultant Changes To Toxicity And Oxidative Stress Of G4 And G6 Poly (Amido Amine) Dendrimer Nanoparticles, Marcus A. Maher, Hugh Byrne

Articles

The mechanism of cellular uptake by endocytosis and subsequent oxidative stress has been identified as the paradigm for the toxic response of cationically surface charged nanoparticles. In an attempt to circumvent the process, the effect of increased cellular membrane permeability on the uptake mechanisms of poly (amidoamine) dendrimers generation 4 (G4) and 6 (G6) in vitro was investigated. Immortalised, non-cancerous human keratinocyte (HaCaT) cells were treated with DL-Buthionine-(S,R)-sulfoximine (BSO). Active uptake of the particles was monitored using fluorescence microscopy to identify and quantify endosomal activity and resultant oxidative stress, manifest as increased levels of reactive oxygen species, monitored using the …

Hawking Radiation Screening And Penrose Process Shielding In The Kerr Black Hole, Eamon Mccaughey

Articles

The radial motion of massive particles in the equatorial plane of aKerr black hole is considered. Screening of the Hawking radiation and shielding of the Penrose process are examined (both inside and outside the ergosphere) and their effect on the evaporation of the black hole is studied. In particular, the locus and width of a classically forbidden region and their dependence on the particle’s angular momentum and energy is analysed. Tunneling of particles between the boundaries of this region is considered and the transmission coefficient determined.

An Effective Method For The Preparation Of High Temperature Stable Anatase Tio2 Photocatalysts, Rachel Fagan, Declan Mccormack, Suresh Pillai, Damian Synnott

Articles

An efficient, rapid and straightforward method for the preparation of nitrogen and fluorine (N, F) codoped high temperature stable anatase using a microwave pre-treatment is reported. Using a single source, ammonium fluoride (NH₄F) for both nitrogen and fluorine, effective doping of the precursor titanium isopropoxide (TTIP) was possible. These samples were characterised for their structural and optical properties using X-ray diffraction (XRD), Fourier transform IR (FTIR), Raman spectroscopy and UV-vis spectroscopy. In terms of the anatase to rutile transition enhancement using a novel microwave assisted technique, the sample prepared in a composition of 1:8 TiO₂: NH …

Chemotherapeutic Efficiency Of Drugs In Vitro: Comparison Of Doxorubicin Exposure In 3d And 2d Culture Matrices, Alan Casey, Mahmoud Gargotti, Franck Bonnier, Hugh Byrne

Articles

The interest in the use of 3D matrices for in vitro analysis, with a view to increasing the relevance of in vitro studies and reducing the dependence on in vivo studies, has been growing in recent years. Cells grown in a 3D in vitro matrix environment have been reported to exhibit significantly different properties to those in a conventional 2D culture environment. However, comparison of 2D and 3D cell culture models have recently been noted to result in differing responses of cytotoxic assays, without any associated change in viability. The effect was attributed to differing conversion rates and effective concentrations …

Open Letter On Ethical Norms In Intellectual Property Scholarship, Robin Feldman, Mark Lemley, Jonathan Masur, Arti K. Rai

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No abstract provided.

The Perverse Effects Of Subsidized Weather Insurance, Omri Ben-Shahar, Kyle D. Logue

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No abstract provided.

Recent Advances In Optical Diagnosis Of Oral Cancers: Review And Future Perspectives, Ola Ibrahim, Hugh Byrne, Fiona Lyng, Surya Singh, Jopi Mikkonen, Arto Koistinen, Arja Kullaa

Articles

Optical diagnosis techniques offer several advantages over traditional approaches, including objectivity, speed and cost, and these label-free, non-invasive methods have the potential to change the future work-flow of cancer management. The oral cavity is particularly accessible and thus such methods may serve as alternate/adjunct tools to traditional methods. Recently, in vivo human clinical studies have been initiated with a view to clinical translation of such technologies. A comprehensive review of optical methods in oral cancer diagnosis is presented. Following an introduction to the epidemiology and aetiological factors associated with oral cancers currently employed diagnostic methods and their limitations are presented. …

Economic Crisis And The Integration Of Law And Finance: The Impact Of Volatility Spikes, Edward G. Fox, Merritt B. Fox, Ronald J. Gilson

Articles

The 2008 financial crisis raised puzzles important for understanding how the capital market prices common stocks and in turn, for the intersection between law and finance. During the crisis, there was a dramatic five-fold spike, across all industries, in “idiosyncratic risk”—the volatility of individual-firm share prices after adjustment for movements in the market as a whole.

This phenomenon is not limited to the most recent financial crisis. This Article uses an empirical review to show that a dramatic spike in idiosyncratic risk has occurred with every major downturn from the 1920s through the recent financial crisis. It canvasses three possible …

Mobilaudio – A Multimodal Content Delivery Platform For Geo-Services, James Carswell, Keith Gardiner, Charlie Cullen

Articles

Delivering high-quality context-relevant information in a timely manner is a priority for location-based services (LBS) where applications require an immediate response based on spatial interaction. Previous work in this area typically focused on ever more accurately determining this interaction and informing the user in the customary graphical way using the visual modality. This paper describes the research area of multimodal LBS and focuses on audio as the key delivery mechanism. This new research extends familiar graphical information delivery by introducing a geoservices platform for delivering multimodal content and navigation services. It incorporates a novel auditory user interface (AUI) that enables …

Spectral Pre And Post Processing For Infrared And Raman Spectroscopy Of Biological Tissues And Cells, Hugh Byrne, Peter Knief, Mark Keating, Franck Bonnier

Articles

Vibrational Spectroscopy, both infrared absorption and Raman spectroscopy, have attracted increasing attention for biomedical applications, from in vivo and ex vivo disease diagnostics and screening, to in vitro screening of therapeutics. There remain, however, many challenges related to the accuracy of analysis of physically and chemically inhomogeneous samples, across heterogeneous sample sets. Data preprocessing is required to deal with variations in instrumental responses and intrinsic spectral backgrounds and distortions in order to extract reliable spectral data. Data postprocessing is required to extract the most reliable information from the sample sets, based on often very subtle changes in spectra associated with …

Acellular Reactivity Of Polymeric Dendrimer Nanoparticles As An Indicator Of Oxidative Stress In Vitro, Marcus Maher, Humza Khalid, Hugh Byrne

Articles

The need for rapid and cost effective pre-screening protocols of the toxicological response of the vast array of emerging nanoparticle types is apparent and the emerging consensus on the paradigm of oxidative stress by generation of intracellular reactive oxygen species as a primary source of the toxic response suggests the development of acellular assays to screen for nanoparticle surface reactivity. This study explores the potential of the monoamine oxidase A (MAO-A) enzyme based assay with polymeric dendrimers as cofactors and serotonin as substrate, which generates H₂O₂, quantified by the conversion of the Carboxy-H₂DCFDA dye …

Second Order Approximation For Heat Conduction: Dissipation Principle And Free Energies, Giovambattista Amendola, Mauro Fabrizio, John Murrough Golden, Barbara Lazzari

Articles

In the context of new models of heat conduction, the second-order approximation of Tzou’s theory, derived by Quintanilla and Racke, has been studied recently by two of the present authors, where it was proved equivalent to a fading memory material. The importance of determining free energy functionals for such materials, and indeed for any material with memory, is emphasized. Because the kernel does not satisfy certain convexity restrictions that allow us to obtain various traditional free energies for materials with fading memory, it is necessary to restrict the study to the minimum and related free energies, which do not require …

Structural Dependence Of The In Vitro Cytotoxicity, Oxidative Stress And Uptake Mechanisms Of Poly(Propylene Imine) Dendritic Nanoparticles, Humza Khalid, Sourav Prasanna Mukherjee, Luke O'Neill, Hugh Byrne

Articles

The in vitro cytotoxic and intracellular oxidative stress responses to exposure to poly (propylene imine) (PPI) dendritic nanoparticles of increasing generation (number of repeated branching cycles) (G0-G4) were assessed in an immortal non-cancerous human keratinocyte cell-line (HaCaT). Confocal fluorescence microscopy with organelle staining was used to explore the uptake and intracellular trafficking mechanisms. A generation and dose dependent cytotoxic response was observed, increasing according to generation and therefore number of surface amino groups. A comparison of the cytotoxic response of G4 PPI and the related G4 Poly (amido amine) dendrimer indicates that the PPI with the same number of surface …

Innovation And Inequality: The Separability Thesis, Richard A. Epstein

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No abstract provided.

Social Accountability: Introducing A New Dimension In Optometric Education, Vanessa Raquel Moodley, James Loughman, Kovin Naidoo

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Optometry globally has undergone major developments yet poor eye health statistics remain. The World Health Organization (WHO) cites social accountability as key to addressing health challenges, urging the education sector to be more socially accountable and train according to the needs of society. A qualitative, descriptive study was used to determine the integration of social accountability within optometric education in sub-Saharan Africa. Eleven academic leaders and two student groups participated in key stakeholder interviews and focus group discussions respectively. Data was thematically analysed using interpretive content analysis. The study found that social accountability policies or practices were not formally integrated …

Atypical Visual And Somatosensory Adaptation In Schizophrenia-Spectrum Disorders, Gizely Andrade, John Butler, Gregory Peter, Sophie Molholm, John J. Foxe

Articles

Neurophysiological investigations in patients with schizophrenia consistently show early sensory processing deficits in the visual system. Importantly, comparable sensory deficits have also been established in healthy first-degree biological relatives of patients with schizophrenia and in first-episode drug-naive patients. The clear implication is that these measures are endophenotypic, related to the underlying genetic liability for schizophrenia. However, there is significant overlap between patient response distributions and those of healthy individuals without affected first-degree relatives. Here we sought to develop more sensitive measures of sensory dysfunction in this population, with an eye to establishing endophenotypic markers with better predictive capabilities. We used …

First Outdoor Characterisation Of A Pv Powered Suspended Particle Device Switchable Glazing, Aritra Ghosh, Brian Norton, Aidan Duffy

Articles

Suspended particle device (SPD) switchable glazing is a candidate intervention to adaptively control solar heat gain. A high voltage low alternating current (AC) to operate a large area SPD applications, can be provided by a photovoltaic (PV) array. The first outdoor characterisation of side-by-side comparison of PV-powered SPD glazing has been conducted. Using an inverter to convert direct current (DC) power from PV to AC a 40 Wp PV device continuously powered a 0.07 W SPD glazing. High inverter power losses were found due to high PV inverter sizing ratio, inverter high self-consumption, and low solar radiation. Low sizing ratio …