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Technological University Dublin

2013

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Articles 1 - 17 of 17

Full-Text Articles in Physics

Manufacture And Investigation Of Organic Composite Polymer Based Films For Advanced Flexible Solar Cells, Raffie Arshak Dec 2013

Manufacture And Investigation Of Organic Composite Polymer Based Films For Advanced Flexible Solar Cells, Raffie Arshak

Masters

Modern society has created big challenges in the area of sustainable supply of energy to satisfy the needs of growing population and to account for depleting fossil fuel resources. The Irish Government has set targets for the energy sector by 2020, with 33% of electricity to be generated from renewable sources. Organic photovoltaic devices offer several advantages over expensive silicon solar cells, including deposition of ultra-thin films by spin-coating, printing and spray-coating. This in turn provides for the exciting possibility to make lightweight, flexible solar cells for a broad range of existing and emerging applications for security, military and medicine. …


Establishing Normative Data For The Visual Skills Of Gaelic Footballers, Valerie Kennelly Nov 2013

Establishing Normative Data For The Visual Skills Of Gaelic Footballers, Valerie Kennelly

Masters

Although sports vision procedures have been implemented in many sports worldwide, no rigorous scientific investigation of the visual skills trends of Gaelic Athletic Association (GAA) participants has been carried out in Ireland to date. The aim of this study was to identify the visual skills required to play Gaelic football and to establish normative data for those skills which can be used to classify, superior, above average, average, below average and inferior visual performance. Hardware visual skills including high and low contrast vision, stereo acuity, colour vision, and contrast sensitivity and software skills including eye hand co-ordination, dynamic fixation and …


Characterization Of Polylactic Acid Films For Food Packaging As Affected By Dielectric Barrier Discharge Atmospheric Plasma, Shashi Pankaj, Luke O'Neill, N. Misra, Paula Bourke Oct 2013

Characterization Of Polylactic Acid Films For Food Packaging As Affected By Dielectric Barrier Discharge Atmospheric Plasma, Shashi Pankaj, Luke O'Neill, N. Misra, Paula Bourke

Articles

Dielectric barrier discharge (DBD) air plasma is a novel technique for in-package decontamination of food, but it has not been yet applied to the packaging material. Characterization of commercial polylactic acid (PLA) films was done after in-package DBD plasma treatment at different voltage and treatment time to evaluate its suitability as food packaging material. DBD plasma increased the roughness of PLA film mainly at the site in contact with high voltage electrode at both the voltage levels of 70 and 80 kV. DBD plasma treatments did not induce any change in the glass transition temperature, but significant increase in the …


Humidity And Temperature Effect On Properties Of Transmission Gratings Recorded In Pva/Aa-Based Photopolymer Layers, Tatsiana Mikulchyk, Suzanne Martin, Izabela Naydenova Oct 2013

Humidity And Temperature Effect On Properties Of Transmission Gratings Recorded In Pva/Aa-Based Photopolymer Layers, Tatsiana Mikulchyk, Suzanne Martin, Izabela Naydenova

Articles

This paper explores the effects of humidity on gratings recorded in a polyvinylalcohol–acrylamide photopolymer medium. Investigation of the behaviour of transmission gratings exposed to high humidity is of significant interest for two reasons, firstly because the grating's sensitivity to humidity can be exploited for the development of irreversible humidity indicators, secondly because too much sensitivity to humidity can limit the use of these materials in applications where an environmentally stable hologram is needed. In this paper we focus on the effect of high humidity on the properties of volume phase transmission gratings recorded in PVA/AA photopolymer layers in the temperature …


Experimental Microwave Breast Cancer Detection With Oil-On-Gelatin Phantom, Giuseppe Ruvio, Raffaele Solimene, Antonio Cuccaro, Jacinta Browne, Domenico Gaetano, Max Ammann Sep 2013

Experimental Microwave Breast Cancer Detection With Oil-On-Gelatin Phantom, Giuseppe Ruvio, Raffaele Solimene, Antonio Cuccaro, Jacinta Browne, Domenico Gaetano, Max Ammann

Conference Papers

Limitations of conventional X-ray mammography has induced a recent interest into radio frequency based diagnostic approaches in order to take advantage of the sharpest dielectric contrast between benign and malignant breast tissues in the microwave frequency range [1]. Dielectric contrast is notably higher than the radiographic density exploited by X-ray mammography. Consequences of the superior sensitivity of RF-based techniques can have a huge social and cost impact. By reducing the false response percent, a dramatic reduction of costs for the health system together with a diminution of traumatic experiences for the patients can be achieved. The antenna properties play a …


Studies Of Shrinkage In Photopolymerisable Materials For Holographic Applications, Mohesh Moothanchery Aug 2013

Studies Of Shrinkage In Photopolymerisable Materials For Holographic Applications, Mohesh Moothanchery

Doctoral

Holography is now firmly established as a tool for scientific and engineering studies and also as a display medium. Holographic performance mainly depends on the choice of recording wavelengths, recording material, recording conditions and experimental setup as well as environmental conditions in the laboratory. Acrylamide based photopolymer has significant advantages as a holographic recording material such as self-development, low scatter, high diffraction efficiency, ease of preparation and low cost. The main objective of this project is to determine and minimise the shrinkage of an acrylamide based photopolymer developed in the Centre for Industrial and Engineering Optics for holographic recording. This …


Design And Study Of Acrylamide-Based Photopolymer Holographic Optical Elements For Solar Application, Hoda Akbari, Izabela Naydenova, Manus Kennedy, John Doran, Suzanne Martin Jun 2013

Design And Study Of Acrylamide-Based Photopolymer Holographic Optical Elements For Solar Application, Hoda Akbari, Izabela Naydenova, Manus Kennedy, John Doran, Suzanne Martin

Conference Papers

Abstract: Solar concentrators can be used to reduce the cost of photovoltaic electrical power generation by collecting incident solar radiation from a given aperture area and transmitting the energy to a reduced area. In doing so, the overall cost of power (Wp) can be reduced as less area of photovoltaic is required. This paper will discuss Holographic Solar Concentrators fabricated in an acrylamide photopolymer , describing the optical recording process and showing how the fabricated HOE’s can be used in solar concentrator devices. Preliminary lifetime studies are also discussed.


Raman Spectroscopic Analysis Of Human Skin Tissue Sections Ex-Vivo: Evaluation Of The Effects Of Tissue Processing And Dewaxing, Syed Mehmood Ali, Franck Bonnier, Ali Tfayli, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne Jun 2013

Raman Spectroscopic Analysis Of Human Skin Tissue Sections Ex-Vivo: Evaluation Of The Effects Of Tissue Processing And Dewaxing, Syed Mehmood Ali, Franck Bonnier, Ali Tfayli, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne

Articles

Raman spectroscopy coupled with K-means clustering analysis (KMCA) is employed to elucidate the biochemical structure of human skin tissue sections, and the effects of tissue processing. Both hand and thigh sections of human cadavers were analysed in their unprocessed and formalin fixed paraffin processed (FFPP) and subsequently dewaxed forms. In unprocessed sections, KMCA reveals clear differentiation of the stratum corneum, intermediate underlying epithelium and dermal layers for sections from both anatomical sites. The stratum corneum is seen to be relatively rich in lipidic content; the spectrum of the subjacent layers is strongly influenced by the presence of melanin, while that …


Cell Death Pathways In Directly Irradiated Cells And Cells Exposed To Medium From Irradiated Cells, K.K. Jella, Amaya Garcia, Brendan Mcclean, Hugh Byrne, Fiona Lyng Mar 2013

Cell Death Pathways In Directly Irradiated Cells And Cells Exposed To Medium From Irradiated Cells, K.K. Jella, Amaya Garcia, Brendan Mcclean, Hugh Byrne, Fiona Lyng

Articles

Purpose: The aim of this study was to compare levels of apoptosis, necrosis, mitotic cell death and senescence after treatment with both direct radiation and irradiated cell conditioned medium. Materials and methods: Human keratinocytes (HaCaT cell line) were irradiated (0.005, 0.05 and 0.5 Gy) using a cobalt 60 teletherapy unit. For bystander experiments, the medium was harvested from donor HaCaT cells one hour after irradiation and transferred to recipient HaCaT cells. Clonogenic assay, apoptosis, necrosis, mitotic cell death, senescence and cell cycle analysis were measured in both directly irradiated cells and bystander cells Results: A reduction in cell survival was …


Research On Holographic Sensors And Novel Photopolymers At The Centre For Industrial And Egnineering Optics, Emilia Mihaylova, Dervil Cody, Izabela Naydenova, Suzanne Martin, Vincent Toal Jan 2013

Research On Holographic Sensors And Novel Photopolymers At The Centre For Industrial And Egnineering Optics, Emilia Mihaylova, Dervil Cody, Izabela Naydenova, Suzanne Martin, Vincent Toal

Books/Book Chapters

The recent resurgence of interest in photopolymers for commercial holograms is a strong incentive for development of photopolymers that are as environmentally friendly as possible. Photopolymer materials consist of a light-sensitive film which is exposed during production to form the hologram, thereby offering versatility well beyond that of current security holograms, which are mass produced from a master using a foil stamping processes.


Raman Spectroscopy In Nanomedicine: Current Status And Future Perspectives, Hugh Byrne, Mark Keating Jan 2013

Raman Spectroscopy In Nanomedicine: Current Status And Future Perspectives, Hugh Byrne, Mark Keating

Articles

Raman spectroscopy is a branch of vibration spectroscopy which is capable of probing the chemical composition of materials. Recent advances in Raman microscopy have added significantly to the range of applications which now extend from medical diagnostics to exploring interfaces between biological organisms and nanomaterials. In this review, Raman is introduced in a general context, highlighting some of the areas in which the technique has found success in the past, as well as some of the potential benefits it offers over other analytical modalities. The subset of Raman techniques which specifically probe the nanoscale, namely Surface Enhanced and Tip Enhanced …


Ultrasound For Improved Crystallisation In Food Processing, N. Misra, Navneet Deora, Brijesh Tiwari, Patrick Cullen Jan 2013

Ultrasound For Improved Crystallisation In Food Processing, N. Misra, Navneet Deora, Brijesh Tiwari, Patrick Cullen

Articles

Within the food industry, controlling crystallisation is a key factor governing food structure, texture and consumer appeal, with some foods requiring the promotion of crystallisation in a controlled manner (e.g. chocolate) and others a check (e.g. in honey). Sonocrystallisation is the application of ultrasound energy to control the nucleation of a crystallisation process. The use of power ultrasound provides a non-invasive approach to producing crystals with desired properties. Sonocrystallisation facilitates process control, primarily by modulating crystal size distribution and morphology. This paper details the governing mechanisms of sonocrystallisation. Proven and potential applications of the process in foods, including chocolates, honey, …


A Comparison Of Three Commercially Available Contrast-Detail Phantoms And Evaluation Of The Contrast-Detail Performance Under A Range Of Instrument Settings, Jacinta Browne, Des Hickey, Ashling Mcnabb Jan 2013

A Comparison Of Three Commercially Available Contrast-Detail Phantoms And Evaluation Of The Contrast-Detail Performance Under A Range Of Instrument Settings, Jacinta Browne, Des Hickey, Ashling Mcnabb

Articles

No abstract provided.


Electric Field Standing Wave Effects In Ft-Ir Transflection Spectra Of Biological Tissue Sections: Simulated Models Of Experimental Variability, Tomasz P. Wrobel, Barbara Wajnchold, Hugh Byrne, Malgorzata Baranska Jan 2013

Electric Field Standing Wave Effects In Ft-Ir Transflection Spectra Of Biological Tissue Sections: Simulated Models Of Experimental Variability, Tomasz P. Wrobel, Barbara Wajnchold, Hugh Byrne, Malgorzata Baranska

Articles

The so-called electric field standing wave effect (EFSW) has recently been demonstrated to significantly distort FT-IR spectra acquired in a transflection mode, both experimentally and in simulated models, bringing into question the appropriateness of the technique for sample characterization, particularly in the field of spectroscopy of biological materials. The predicted effects are most notable in the regime where the sample thickness is comparable to the source wavelength. In this work, the model is extended to sample thicknesses more representative of biological tissue sections and to include typical experimental factors which are demonstrated to reduce the predicted effects. These include integration …


A Comparison Of Raman, Ftir And Atr-Ftir Micro Spectroscopy For Imaging Human Skin Tissue Sections., Syed Mehmood Ali, Franck Bonnier, Helen Lambkin, Kathleen Flynn, V Mcdonagh, Claragh Healy, T C. Lee, Fiona Lyng, Hugh Byrne Jan 2013

A Comparison Of Raman, Ftir And Atr-Ftir Micro Spectroscopy For Imaging Human Skin Tissue Sections., Syed Mehmood Ali, Franck Bonnier, Helen Lambkin, Kathleen Flynn, V Mcdonagh, Claragh Healy, T C. Lee, Fiona Lyng, Hugh Byrne

Articles

Raman and Infrared absorption spectroscopies are compared for the analysis of human hand skin tissue sections. The tissue sections have been formalin fixed and paraffin processed, and subsequently dewaxed. Fourier Transform infrared (FTIR) spectra are preprocessed using the resonant Mie – extended multiplicative scattering algorithm to remove spectral artefacts. FTIR images of resolution 4cm-1, analysed using K-means cluster analysis, reveal the double layer structure of the dermis and epidermis, but no further layer differentiation is achieved using the higher spatial resolution of the Attenuated Total Reflection imaging or improved spectral resolution of 2cm-1. At comparable spectral …


Raman Micro Spectroscopy Study Of The Interaction Of Vincristine With A549 Cells Supported By Expression Analysis Of Bcl-2 Protein, Haq Nawaz, Amaya Garcia, Aidan Meade, Fiona Lyng, Hugh Byrne Jan 2013

Raman Micro Spectroscopy Study Of The Interaction Of Vincristine With A549 Cells Supported By Expression Analysis Of Bcl-2 Protein, Haq Nawaz, Amaya Garcia, Aidan Meade, Fiona Lyng, Hugh Byrne

Articles

Understanding the interaction of anticancer drugs with model cell lines is important to elucidate the mode of action of these drugs as well as to develop cost effective and rapid screening methods. Raman spectroscopy has been demonstrated to be a valuable technique for high throughput, noninvasive analysis. The interaction of vincristine with a human lung adenocarcinoma cell line (A549)was investigated using Raman micro spectroscopy. The results were correlated with parallel measurements from the MTT cytotoxicity assay, which yielded an IC50 value of 0.10 ± 0.03 μM. The Raman spectral data acquired from vincristine treated A549 cells was analysed to …


The Bio-Nano-Interface In Predicting Nanoparticle Fate And Behaviour In Living Organisms: Towards Grouping And Categorising Nanomaterials And Ensuring Nanosafety By Design, Hugh Byrne, Arti Ahluwalia, Diana Boraschi,, Bengt Fadeel, Peter Gehr, Arno C. Gutleb, Michaela Kendall, Manthos Papadopoulos, Iseult Lynch Jan 2013

The Bio-Nano-Interface In Predicting Nanoparticle Fate And Behaviour In Living Organisms: Towards Grouping And Categorising Nanomaterials And Ensuring Nanosafety By Design, Hugh Byrne, Arti Ahluwalia, Diana Boraschi,, Bengt Fadeel, Peter Gehr, Arno C. Gutleb, Michaela Kendall, Manthos Papadopoulos, Iseult Lynch

Articles

In biological media, nanoparticles acquire a coating of biomolecules (proteins, lipids, polysaccharides) from their surroundings, which reduces their surface energy and confers a biological identity to the particles. This adsorbed layer is the interface between the nanomaterial and living systems and therefore plays a significant role in determining the fate and behaviour of the nanoparticles. This review summarises the state of the art in terms of understanding the bio-nano interface and provides direction for potential future research directions and some recommendations for future priorities and strategies to support the safe implementation of nanotechnologies. The central premise is that nanomaterials must …