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Full-Text Articles in Physics

The Prospect Of Microwave Heating: Towards A Faster And Deeper Crack Healing In Asphalt Pavement, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen Mar 2021

The Prospect Of Microwave Heating: Towards A Faster And Deeper Crack Healing In Asphalt Pavement, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

Articles

Microwave heating has been shown to be an effective method of heating asphalt concrete and in turn healing the damage. As such, microwave heating holds great potential in rapid (1–3 min) and effective damage healing, resulting in improvement in the service life, safety, and sustainability of asphalt pavement. This study focused on the microwave healing effect on porous asphalt concrete. Steel wool fibres were incorporated into porous asphalt to improve the microwave heating efficiency, and the optimum microwave heating time was determined. Afterwards, the microwave healing efficiency was evaluated using a semi–circular bending and healing programme. The results ...


Acute Growth Inhibition & Toxicity Analysis Of Nano-Polystyrene Spheres On Raphidocelis Subcapitata, A. Reynolds, Michelle Giltrap, Gordon Chambers Jan 2021

Acute Growth Inhibition & Toxicity Analysis Of Nano-Polystyrene Spheres On Raphidocelis Subcapitata, A. Reynolds, Michelle Giltrap, Gordon Chambers

Articles

Micro/nano-plastics (MNPs) have been found within many environments and organisms including humans, making them a significant and growing concern. Initial research into the potential detrimental effects these MNPs both from acute and chronic exposure has been ongoing but still requires substantially more data to clarify. This research presents the response of nano-polystyrene (NPS) on Raphidocelis subcapitata, a freshwater alga, under an existing acute toxicity test along with additional analytical techniques to try identifying possible sources of toxicity. R. subcapitata cells were exposed for 72 h to a concentration range of 0–100 mg/l NPS. Growth Inhibition (GI) testing ...


Semiclassical Backreaction On Asymptotically Anti–De Sitter Black Holes, Peter Taylor, Cormac Breen Jan 2021

Semiclassical Backreaction On Asymptotically Anti–De Sitter Black Holes, Peter Taylor, Cormac Breen

Articles

We consider a quantum scalar field on the classical background of an asymptotically anti–de Sitter black hole and the backreaction the field’s stress-energy tensor induces on the black hole geometry. The backreaction is computed by solving the reduced-order semiclassical Einstein field equations sourced by simple analytical approximations for the renormalized expectation value of the scalar field stress-energy tensor. When the field is massless and conformally coupled, we adopt Page’s approximation to the renormalized stress-energy tensor, while for massive fields we adopt a modified version of the DeWitt-Schwinger approximation. The latter approximation must be modified so that it ...


Enhancing The Visibility Of Vernier Effect In A Tri-Microfiber Coupler Fiber Loop Interferometer For Ultrasensitive Refractive Index And Temperature Sensing, Fangfang Wei, Dejun Liu, Zhe Wang, Zhuochen Wang, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova Nov 2020

Enhancing The Visibility Of Vernier Effect In A Tri-Microfiber Coupler Fiber Loop Interferometer For Ultrasensitive Refractive Index And Temperature Sensing, Fangfang Wei, Dejun Liu, Zhe Wang, Zhuochen Wang, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova

Articles

In this paper a Vernier effect based sensor is analyzed and demonstrated experimentally in a tri-microfiber coupler (Tri-MFC) and polarization-maintaining fiber (PMF) loop interferometer (Tri-MFC-PMF) to provide ultrasensitive refractive index and temperature sensing. The main novelty of this work is an analysis of parameters of the proposed Tri-MFC-PMF with the objective of determining the conditions leading to a strong Vernier effect. It has been identified by simulation that the Vernier effect is a primary factor in the design of Tri-MFC-PMF loop sensing structure for sensitivity enhancement. It is furthermore demonstrated experimentally that enhancing the visibility of the Vernier spectrum in ...


Can Ethanol Affect The Cell Structure - A Dynamic Molecular And Raman Spectroscopy Study, Luis Felipe Carvalho, Laurita Dos Santos, Kate O'Callaghan, Franck Bonnier, Steven Flint, Fiona Lyng, Hugh Byrne Feb 2020

Can Ethanol Affect The Cell Structure - A Dynamic Molecular And Raman Spectroscopy Study, Luis Felipe Carvalho, Laurita Dos Santos, Kate O'Callaghan, Franck Bonnier, Steven Flint, Fiona Lyng, Hugh Byrne

Articles

The role that tobacco consumption plays in the etiology of oral cancer carcinogenesis, and of alcohol consumption acting as a co-factor, have been well established. However, in recent years, the contribution of alcohol consumption alone to oral cancer has been proposed. In fact, a high percentage of patients who develop oral cancer have both habits (tobacco and alcohol consumption), and other small patient groups only consume alcohol or do not have any other identifiable bad habits. In the present study, we demonstrate for the first time, using a combination of dynamic molecular modelling and Raman spectroscopy, that ethanol has a ...


Quantitative Analysis Of Human Blood Serum Using Vibrational Spectroscopy., Hugh Byrne, Franck Bonnier, Jennifer Mcintyre, Drishya Rajan Parachalil Jan 2020

Quantitative Analysis Of Human Blood Serum Using Vibrational Spectroscopy., Hugh Byrne, Franck Bonnier, Jennifer Mcintyre, Drishya Rajan Parachalil

Articles

Analysis of bodily fluids using vibrational spectroscopy has attracted increasing attention in recent years. In particular, infrared spectroscopic screening of blood products, particularly blood serum, for disease diagnostics has been advanced considerably, attracting commercial interests. However, analyses requiring quantification of endogenous constituents or exogenous agents in blood are less well advanced. Recent advances towards this end are reviewed, focussing on infrared and Raman spectroscopic analyses of human blood serum. The importance of spectroscopic analysis in the native aqueous environment is highlighted, and the relative merits of infrared absorption versus Raman spectroscopy are considered, in this context. It is argued that ...


A Catalogue Of Locus Algorithm Pointings For Optimal Differential Photometry For 23,779 Quasars, Oisın Creaner, Kevin Nolan, David Grennan, Niall Smith, Eugene Hickey Jan 2020

A Catalogue Of Locus Algorithm Pointings For Optimal Differential Photometry For 23,779 Quasars, Oisın Creaner, Kevin Nolan, David Grennan, Niall Smith, Eugene Hickey

Articles

This paper presents a catalogue of optimised pointings for differential photometry of23,779 quasars extracted from the Sloan Digital Sky Survey (SDSS) Catalogue and ascore for each indicating the quality of the Field of View (FoV) associated with thatpointing. Observation of millimagnitude variability on a timescale of minutes typicallyrequires differential observations with reference to an ensemble of reference stars. Foroptimal performance, these reference stars should have similar colour and magnitudeto the target quasar. In addition, the greatest quantity and quality of suitable refer-ence stars may be found by using a telescope pointing which offsets the target objectfrom the centre of ...


Silicon Microcantilever Sensors To Detect The Reversible Conformational Change Of A Molecular Switch, Spiropyan, Catherine M. Grogan, George Amarandei, Shauna Lawless, Francis Pedreschi, Fiona Lyng, Fernando Benito-Lopez, Roberto Raiteri, Laisa Florea Jan 2020

Silicon Microcantilever Sensors To Detect The Reversible Conformational Change Of A Molecular Switch, Spiropyan, Catherine M. Grogan, George Amarandei, Shauna Lawless, Francis Pedreschi, Fiona Lyng, Fernando Benito-Lopez, Roberto Raiteri, Laisa Florea

Articles

The high sensitivity of silicon microcantilever sensors has expanded their use in areas ranging from gas sensing to bio-medical applications. Photochromic molecules also represent promising candidates for a large variety of sensing applications. In this work, the operating principles of these two sensing methods are combined in order to detect the reversible conformational change of a molecular switch, spiropyran. Thus, arrays of silicon microcantilever sensors were functionalized with spiropyran on the gold covered side and used as test microcantilevers. The microcantilever deflection response was observed, in five sequential cycles, as the transition from the spiropyran (SP) (CLOSED) to the merocyanine ...


Polyvinyl Alcohol Cryogel Based Vessel Mimicking Material For Modelling The Progression Of Atherosclerosis, Andrew Malone, Sean Cournane, Izabela Naydenova, Andrew J. Fagan, Jacinta Browne Jan 2020

Polyvinyl Alcohol Cryogel Based Vessel Mimicking Material For Modelling The Progression Of Atherosclerosis, Andrew Malone, Sean Cournane, Izabela Naydenova, Andrew J. Fagan, Jacinta Browne

Articles

Purpose

The stiffness of Polyvinyl-alcohol cryogel can be adjusted through application of consecutive freeze-thaw cycles. This material has potential applications in the production of tissue mimicking phantoms in diagnostic ultrasound. The aim of this study was to use PVA-c to produce a range of geometrically and acoustically identical vessel phantoms modelling stages of atherosclerosis which could be verified through mechanical testing, thus allowing for more precision in quantitative in-vitro flow analysis of atherosclerosis.

Methods

A series of anatomically realistic walled renal artery flow phantoms were constructed using PVA-c. In order to ensure precise modelling of atherosclerosis, a modified procedure of ...


Empirical Study On The Effects Of Acquisition Parameters For Ftir Hyperspectral Imaging Of Brain Tissue, David Perezguaita, Julia Sacharz, Mustafa Kasniz, Shaiju Nazeer, Bayden Wood, Philip Heraud Jan 2020

Empirical Study On The Effects Of Acquisition Parameters For Ftir Hyperspectral Imaging Of Brain Tissue, David Perezguaita, Julia Sacharz, Mustafa Kasniz, Shaiju Nazeer, Bayden Wood, Philip Heraud

Articles

Fourier transform infrared (FTIR) spectroscopic imaging is a powerful technique for molecular imaging of pathologies associated with the nervous systems including multiple sclerosis research. However, there is no standard methodology or standardized protocol for FTIR imaging of tissue sections that maximize the ability to discriminate between the molecular, white and granular layers, which is essential in the investigation of the mechanism of demyelination process. Tissue sections are heterogeneous, complex and delicate, hence the parameters to generate high quality images in minimal time becomes essential in the modern clinical laboratory. This article presents an FTIR spectroscopic imaging study of post-mortem human ...


Discriminant Analysis And Feature Selection In Mass Spectrometry Imaging Using Constrained Repeated Random Sampling - Cross Validation (Corrs-Cv), David Perezguaita, Julia Kuligowsky, Guillermo Quintas Jan 2020

Discriminant Analysis And Feature Selection In Mass Spectrometry Imaging Using Constrained Repeated Random Sampling - Cross Validation (Corrs-Cv), David Perezguaita, Julia Kuligowsky, Guillermo Quintas

Articles

No abstract provided.


A Vibrational Spectroscopic Based Approach For Diagnosing Babesia Bovis Infection, Anja Ruther, David Perezguaita, William Poole, Brian Cooke, Carlos Suarez, Philip Heraud, Bayden Wood Jan 2020

A Vibrational Spectroscopic Based Approach For Diagnosing Babesia Bovis Infection, Anja Ruther, David Perezguaita, William Poole, Brian Cooke, Carlos Suarez, Philip Heraud, Bayden Wood

Articles

Babesia bovis parasites present a serious and significant health concern for the beef and dairy industries in many parts of the world. Difficulties associated with the current diagnostic techniques include they are prone to human error (microscopy) or expensive and time consuming (Polymerase Chain Reaction) to perform. Little is known about the biochemical changes in blood that are associated with Babesia infections. The discovery of new biomarkers will lead to improved diagnostic outcomes for the cattle industry. Vibrational spectroscopic technologies can record a chemical snapshot of the entire organism and the surrounding cell thereby providing a phenotype of the organism ...


Towards A Rapid Screening Of Liver Grafts At The Operating Room Using Mid-Infrared Spectroscopy, David Perezguaita, Marta Moreno Torres, Ramiro Jover, Eugenia Pareja, Bernard Lendl, Julia Kuligowsky, Guillermo Quintas Jan 2020

Towards A Rapid Screening Of Liver Grafts At The Operating Room Using Mid-Infrared Spectroscopy, David Perezguaita, Marta Moreno Torres, Ramiro Jover, Eugenia Pareja, Bernard Lendl, Julia Kuligowsky, Guillermo Quintas

Articles

The estimation of steatosis in a liver graft is mandatory prior to liver transplantation, as the risk of graft failure increases with the level of infiltrated fat. However, the assessment of liver steatosis before transplantation is typically based on a qualitative or semiquantitative characterization by visual inspection and palpation and histological analysis. Thus, there is an unmet need for transplantation surgeons to have access to a diagnostic tool enabling an in situ fast classification of grafts prior to extraction. In this study, we have assessed an attenuated total reflection−Fourier transform infrared (ATR−FTIR) spectroscopic method compatible with the requirements ...


Birefringent Optofluidic Gratings, Sergio Calixto, Jose L. Garcia-Cordero, Diana F. Cedillo-Alcantar, Izabela Naydenova, Guillermo Garnica Jan 2020

Birefringent Optofluidic Gratings, Sergio Calixto, Jose L. Garcia-Cordero, Diana F. Cedillo-Alcantar, Izabela Naydenova, Guillermo Garnica

Articles

A set of parallel microfluidic channels behaving as a diffraction grating operating in the Raman-Nath regime has been fabricated and studied. The diffraction efficiency of such structure can be tuned by selecting a liquid with a particular refractive index and/or optical anisotropy. Alternatively the optical properties of the liquid can be characterised by measuring the diffraction efficiency and the state of polarization of the diffracted beam. In this work, the microfluidic channels under study have been filled with penicillin molecules dissolved in water. Due to the chirality of the penicillin, the liquid has been found to have circular birefringence ...


Liposomal Encapsulation Of Silver Nanoparticles To Enhance Nanoparticle Cytotoxicity And Modulate Induced Inflammatory Responses In Vitro, Azeez Yusuf Jan 2020

Liposomal Encapsulation Of Silver Nanoparticles To Enhance Nanoparticle Cytotoxicity And Modulate Induced Inflammatory Responses In Vitro, Azeez Yusuf

Doctoral

High concentrations of silver nanoparticles (AgNP) are increasingly present as active ingredient in everyday consumable products for antibacterial purposes causing increased human exposure and high risk of adverse effect development. In this thesis, AgNP were encapsulated in dipalmitoyl phosphatidylcholine (DPPC)-based liposome (forming Lipo-AgNP), to enhance intracellular delivery and associated cytotoxicity, and suppress AgNP-induced inflammation. It was noted that as a result of the encapsulation, Lipo-AgNP induced significantly reduced cell viability of THP1 monocytes and THP1 differentiated macrophages (TDM) at a notably lower dose than that of uncoated AgNP. The induced cytotoxicity was shown to result in an increased level ...


Swirling Fluid Flow In Flexible, Expandable Elastic Tubes: Variational Approach, Reductions And Integrability, Rossen Ivanov, Vakhtang Putkaradze Jan 2020

Swirling Fluid Flow In Flexible, Expandable Elastic Tubes: Variational Approach, Reductions And Integrability, Rossen Ivanov, Vakhtang Putkaradze

Articles

Many engineering and physiological applications deal with situations when a fluid is moving in flexible tubes with elastic walls. In real-life applications like blood flow, a swirl in the fluid often plays an important role, presenting an additional complexity not described by previous theoretical models. We present a theory for the dynamics of the interaction between elastic tubes and swirling fluid flow. The equations are derived using a variational principle, with the incompressibility constraint of the fluid giving rise to a pressure-like term. In order to connect this work with the previous literature, we consider the case of inextensible and ...


On The Intermediate Long Wave Propagation For Internal Waves In The Presence Of Currents, Joseph Cullen, Rossen Ivanov Jan 2020

On The Intermediate Long Wave Propagation For Internal Waves In The Presence Of Currents, Joseph Cullen, Rossen Ivanov

Articles

A model for the wave motion of an internal wave in the presence of current in the case of intermediate long wave approximation is studied. The lower layer is considerably deeper, with a higher density than the upper layer. The flat surface approximation is assumed. The fluids are incompressible and inviscid. The model equations are obtained from the Hamiltonian formulation of the dynamics in the presence of a depth-varying current. It is shown that an appropriate scaling leads to the integrable Intermediate Long Wave Equation (ILWE). Two limits of the ILWE leading to the integrable Benjamin-Ono and KdV equations are ...


Development Of Photopolymer Material With Improved Dynamic Range And Sensitivity, Brian Rogers, Izabela Naydenova, Suzanne Martin Sep 2019

Development Of Photopolymer Material With Improved Dynamic Range And Sensitivity, Brian Rogers, Izabela Naydenova, Suzanne Martin

Conference Papers

In this study the effect of the concentration of acrylamide and the influence of different initiators in a photopolymer composition for holographic recording of diffraction gratings is investigated. Light manipulating Holographic Optical Elements (HOEs) have a number of characteristics which can be optimised for different roles. However, at the core of these devices is the refractive index modulation that has been created in the material during recording. Typically higher refractive index modulation will enable greater diffraction efficiency. Solar concentrating HOEs can particularly benefit from material that experiences higher refractive index modulation. For a solar concentrator to have a high acceptance ...


Study Of The Effect Of Magnetic Nanoparticles On The Hologram Recording Capability Of Photopolymer Nanocomposite For Development Of Holographic Sensor/Actuator, Muhammad Irfan, Suzanne Martin, Izabela Naydenova Sep 2019

Study Of The Effect Of Magnetic Nanoparticles On The Hologram Recording Capability Of Photopolymer Nanocomposite For Development Of Holographic Sensor/Actuator, Muhammad Irfan, Suzanne Martin, Izabela Naydenova

Conference Papers

Photopolymer nanocomposite materials utilising nanoparticles of varied refractive index are one of the most attractive materials for holography due to their tuneable properties. The preparation of the photopolymer nanocomposites can involve mixing a stable colloidal suspension in the photopolymer solution or printing of the nanoparticle colloidal suspension on top of a dried photopolymer layer. By following the first approach in this study a novel photopolymer nanocomposite material is prepared for holographic recording. It consists of N-isopropylacrylamide (NIPA)-based photopolymer as a host and iron oxide magnetic nanoparticles as nanodopant. The methodology of the photopolymer nanocomposite material preparation is explained in ...


An Investigation Of The Detection Capability Of Pulsed Wave Duplex Doppler Of Low Grade Stenosis Using Ultrasound Contrast Agent Microbubbles – An In-Vitro Study, Jacinta Browne, Deirdre King, Andrew Fagan, Deepa Chari, Carmel Moran Apr 2019

An Investigation Of The Detection Capability Of Pulsed Wave Duplex Doppler Of Low Grade Stenosis Using Ultrasound Contrast Agent Microbubbles – An In-Vitro Study, Jacinta Browne, Deirdre King, Andrew Fagan, Deepa Chari, Carmel Moran

Articles

Objective: The objective of the study was to investigate whether clinically used ultrasonic contrast agents improved the accuracy of spectral Doppler ultrasound in the detection of low grade (< 50%) renal artery stenosis. Low grade stenoses in the renal artery are notoriously difficult to reliably detect using Doppler ultrasound due to difficulties such as overlying fat and bowel gas.

Methods: A range of anatomically-realistic renal artery phantoms with varying low degrees of stenosis (0, 30 and 50%) were constructed and peak velocity data was measured from within the pre-stenotic and mid-stenotic regions in each phantom, for both unenhanced and contrast-enhanced spectral Doppler data acquisitions. The effect of a 20mm overlying fat layer on the ultrasound beam distortion and phase aberration, and hence on the measured peak velocity data, was also investigated ...


Use Of Novel Anthropomorphic Breast Ultrasound Phantoms For Radiology Resident Education, Jacinta Browne, Chris Gu, Robert Fazzio, Andrew Fagan, Donald Tradup, Nicholas Hangiandreou Feb 2019

Use Of Novel Anthropomorphic Breast Ultrasound Phantoms For Radiology Resident Education, Jacinta Browne, Chris Gu, Robert Fazzio, Andrew Fagan, Donald Tradup, Nicholas Hangiandreou

Articles

Purpose: This study evaluated the training and assessment role of anthropomorphic breast ultrasound phantoms which simulated both the morphological and sonographic characteristics of breast tissue, including lesions, in a group of radiology residents at a large academic medical center. Methods: This was a prospective study involving 9 residents across all years (2nd–4th year) of a radiology residency program. Baseline assessments of all residents ability to detect and characterize lesions in P-I were carried out, followed by a two-hour teaching session on the same phantom. All residents underwent a post-training, final assessment on P-II to evaluate changes in ...


Magnetic Field Sensor Based On A Tri-Microfiber Coupler Ring In Magnetic Fluid And A Fiber Bragg Grating, Fangfang Wei, Dejun Liu, Arun Kumar Mallik, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova Jan 2019

Magnetic Field Sensor Based On A Tri-Microfiber Coupler Ring In Magnetic Fluid And A Fiber Bragg Grating, Fangfang Wei, Dejun Liu, Arun Kumar Mallik, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova

Articles

In this paper we propose and investigate a novel magnetic field sensor based on a Tri-microfiber coupler combined with magnetic fluid and a fiber Bragg grating (FBG) in a ring. A sensitivity of 1306 pm/mT was experimentally demonstrated in the range of magnetic fields from 0 to 15 mT. The reflection peak in the output spectrum associated with the FBG serves as a reference point allowing to avoid ambiguity in determining the spectral shift induced by the magnetic field. Due to its high sensitivity at low magnetic fields, the proposed structure could be of high interest in low field ...


Sns Optical Fiber Structure Sensor For Direct Detection Of The Phase Transition In C18h38 N-Alkane Material, Wei Han, Marek Rebow, Xiaokang Lian, Dejun Liu, Gerald Farrell, Qiang Wu, Yuliya Semenova Jan 2019

Sns Optical Fiber Structure Sensor For Direct Detection Of The Phase Transition In C18h38 N-Alkane Material, Wei Han, Marek Rebow, Xiaokang Lian, Dejun Liu, Gerald Farrell, Qiang Wu, Yuliya Semenova

Articles

A singlemode-no-core-singlemode (SNS) fiber structure optical sensor for detecting the solid-liquid phase change in a phase change material: C18H38 n-alkane material (n-octadecane) is proposed and demonstrated. The transmission-type sensor probe consists of a short section of no-core fiber sandwiched between two sections of a singlemode fiber. Phase changes in n-octadecane are accompanied by large step-like variations of its refractive index (RI). Such a large discontinuous change of the n-octadecane’s RI during its phase transition, leads to the corresponding step-like change in the transmitted optical power that can reliably indicate the phase change of the sample in the vicinity of ...


Multivariate Statistical Methodologies Used In In-Vitro Raman Spectroscopy: Simulations And Applications For Drug And Nanoparticle Interactions, Mark Edward Keating Jan 2019

Multivariate Statistical Methodologies Used In In-Vitro Raman Spectroscopy: Simulations And Applications For Drug And Nanoparticle Interactions, Mark Edward Keating

Doctoral

Raman spectroscopy is a growing technology in the fields of in-vitro drug and nanoparticle screening. The label free capability provided by vibrational spectroscopy, as well as the ability of the technique to probe the chemical nature of samples, makes it a good candidate for use in these fields. Crucial to the progress of these methods is the development and validation of robust and accurate multivariate statistical analysis protocols. In this thesis, both established and novel methods are examined using both real and simulated datasets. In particular, simulated datasets are used to validate and assess the accuracy of these methods in ...


Exploring Subcellular Responses Of Prostate Cancer Cells To X-Ray Exposure By Raman Mapping, Maciej Roman, Agnieszka Panek, Hugh J. Byrne, Tomasz P Wrobel, Esen Efeoglu, Czeslawa Paluszkiewicz, Wojciech Maria Kwiatek Jan 2019

Exploring Subcellular Responses Of Prostate Cancer Cells To X-Ray Exposure By Raman Mapping, Maciej Roman, Agnieszka Panek, Hugh J. Byrne, Tomasz P Wrobel, Esen Efeoglu, Czeslawa Paluszkiewicz, Wojciech Maria Kwiatek

Articles

Understanding the response of cancer cells to ionising radiation is a crucial step in modern radiotherapy. Raman microspectroscopy, together with Partial Least Squares Regression (PLSR) analysis has been shown to be a powerful tool for monitoring biochemical changes of irradiated cells on the subcellular level. However, to date, the majority of Raman studies have been performed using a single spectrum per cell, giving a limited view of the total biochemical response of the cell. In the current study, Raman mapping of the whole cell area was undertaken to ensure a more comprehensive understanding of the changes induced by X-ray radiation ...


Surface Waves Over Currents And Uneven Bottom, Alan Compelli, Rossen Ivanov, Calin I. Martin, Michail D. Todorov Jan 2019

Surface Waves Over Currents And Uneven Bottom, Alan Compelli, Rossen Ivanov, Calin I. Martin, Michail D. Todorov

Articles

The propagation of surface water waves interacting with a current and an uneven bottom is studied. Such a situation is typical for ocean waves where the winds generate currents in the top layer of the ocean. The role of the bottom topography is taken into account since it also influences the local wave and current patterns. Specific scaling of the variables is selected which leads to approximations of Boussinesq and KdV types. The arising KdV equation with variable coefficients, dependent on the bottom topography, is studied numerically when the initial condition is in the form of the one soliton solution ...


Equatorial Wave–Current Interactions, Adrian Constantin, Rossen Ivanov Jan 2019

Equatorial Wave–Current Interactions, Adrian Constantin, Rossen Ivanov

Articles

We study the nonlinear equations of motion for equatorial wave–current interactions in the physically realistic setting of azimuthal two-dimensional inviscid flows with piecewise constant vorticity in a two-layer fluid with a flat bed and a free surface. We derive a Hamiltonian formulation for the nonlinear governing equations that is adequate for structure-preserving perturbations, at the linear and at the nonlinear level. Linear theory reveals some important features of the dynamics, highlighting differences between the short- and long-wave regimes. The fact that ocean energy is concentrated in the long-wave propagation modes motivates the pursuit of in-depth nonlinear analysis in the ...


Raman Spectroscopy Detects Biochemical Changes Due To Different Cell Culture Environments In Live Cells In Vitro, Mahmoud Gargotti, Esen Efeoglu, Hugh J Byrne, Alan Casey Oct 2018

Raman Spectroscopy Detects Biochemical Changes Due To Different Cell Culture Environments In Live Cells In Vitro, Mahmoud Gargotti, Esen Efeoglu, Hugh J Byrne, Alan Casey

Articles

The in vitro cell culture environment can impact on cell biochemistry and cell cycle. The manifestation of such substrate-induced changes in cell cycle in the Raman microspectroscopic profiles of cell cultures is investigated at the level of nucleolus, nucleus and cytoplasm. HeLa immortalised human cervical cells and HaCaT dermal cells were cultured on three different substrates, conventional polystyrene cell culture dishes, CaF2 slides as a commonly used Raman substrate, and glass slides coated with Collagen Rat Tail, as a mimic of the extra cellular matrix (ECM) environment. A cell cycle study, based on percentage DNA content, as determined using Propidium ...


Significance Of A Non-Thermal Plasma Treatment On Ldpe Biodegradation With Pseudomonas Aeruginosa, Laurence Scally, Miroslav Gulan, Lars Weigang, Patrick Cullen, Vladimir Milosavljevic Oct 2018

Significance Of A Non-Thermal Plasma Treatment On Ldpe Biodegradation With Pseudomonas Aeruginosa, Laurence Scally, Miroslav Gulan, Lars Weigang, Patrick Cullen, Vladimir Milosavljevic

Articles

The use of plastics has spanned across almost all aspects of day to day life. Although their uses are invaluable, they contribute to the generation of a lot of waste products that end up in the environment and end up polluting natural habitats such as forests and the ocean. By treating low-density polyethylene (LDPE) samples with non-thermal plasma in ambient air and with an addition of 4% CO2, the biodegradation of the samples can be increased due to an increase in oxidative species causing better cell adhesion and acceptance on the polymer sample surface. It was, however, found that the ...


The Influence Of Soft Contact Lens Materials On The Central, Para-Central And Peripheral Corneal Endothelium, Aoife Lloyd Mckernan, Luisa Simo Mannion, Veronica O'Dwyer Aug 2018

The Influence Of Soft Contact Lens Materials On The Central, Para-Central And Peripheral Corneal Endothelium, Aoife Lloyd Mckernan, Luisa Simo Mannion, Veronica O'Dwyer

Other Resources

Title: The influence of soft contact lens materials on the central, para-central and peripheral corneal endothelium prior to and following two weeks cessation of soft contact lens wear.

Purpose: To examine the influence of a variety of soft contact lens (SCL) materials on the central, para-central and peripheral corneal endothelium measurements, prior to and following two weeks cessation of SCL wear.

Methods: Endothelial measurements were taken using the CEM-530 (Nidek, Japan) specular microscope. Full-time SCL wearers (n = 31 eyes) were compared to a non-contact lens (NCL) control group (n = 28 eyes) of a similar age. Seven areas of the endothelium ...