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Isolation, Purification And Characterization Of A Novel Solvent Stable Lipase From Pseudomonas Reinekei, Barry Ryan, Priyanka Priyanka, Gemma K. Kinsella, Gary T. Henehan Sep 2018

Isolation, Purification And Characterization Of A Novel Solvent Stable Lipase From Pseudomonas Reinekei, Barry Ryan, Priyanka Priyanka, Gemma K. Kinsella, Gary T. Henehan

Articles

The Pseudomonas sp. have been long recognized for their exogenous lipolytic activities yet the genus still contains a lot of unexplored strains. Due to the versatile metabolic machinery and their potential for adaptation to fluctuating environmental conditions Pseudomonas sp. are of great interest for biotechnological applications. In this study, a new extracellularly produced lipolytic enzyme from Pseudomonas sp. (P. reinekei) was purified and characterized. The production of lipase from P. reinekei (H1) was enhanced 10-fold by optimizing the nitrogen source. The 50 kDa H1 lipase was purified using negative and positive mode anion exchange chromatography. The purified lipase was active …


Innovation In Rangeland Monitoring: Annual, 30 M, Plant Functional Type Percent Cover Maps For U.S. Rangelands, 1984-2017, Matthew O. Jones, Brady W. Allred, David E. Naugle, Jeremy D. Maestas, Patrick Donnelly, Loretta J. Metz, Jason Karl, Rob Smith, Brandon Bestelmeyer, Chad Boyd, Jay D. Kerby, James D. Mciver Sep 2018

Innovation In Rangeland Monitoring: Annual, 30 M, Plant Functional Type Percent Cover Maps For U.S. Rangelands, 1984-2017, Matthew O. Jones, Brady W. Allred, David E. Naugle, Jeremy D. Maestas, Patrick Donnelly, Loretta J. Metz, Jason Karl, Rob Smith, Brandon Bestelmeyer, Chad Boyd, Jay D. Kerby, James D. Mciver

Articles

Innovations in machine learning and cloud‐based computing were merged with historical remote sensing and field data to provide the first moderate resolution, annual, percent cover maps of plant functional types across rangeland ecosystems to effectively and efficiently respond to pressing challenges facing conservation of biodiversity and ecosystem services. We utilized the historical Landsat satellite record, gridded meteorology, abiotic land surface data, and over 30,000 field plots within a Random Forests model to predict per‐pixel percent cover of annual forbs and grasses, perennial forbs and grasses, shrubs, and bare ground over the western United States from 1984 to 2017. Results were …


Potential Of Red Edge Spectral Bands In Future Landsat Satellites On Agroecosystem Canopy Green Leaf Area Index Retrieval, Zhaoyu Cui, John Kerekes Sep 2018

Potential Of Red Edge Spectral Bands In Future Landsat Satellites On Agroecosystem Canopy Green Leaf Area Index Retrieval, Zhaoyu Cui, John Kerekes

Articles

Vegetation biophysical parameter retrieval is an important earth remote sensing system application. In this paper, we studied the potential impact of the addition of new spectral bands in the red edge region in future Landsat satellites on agroecosystem canopy green leaf area index (LAI) retrieval. The test data were simulated from SPARC ‘03 field campaign HyMap hyperspectral data. Three retrieval approaches were tested: empirical regression based on vegetation index, physical model-based look-up-table (LUT) inversion, and machine learning. The results of all three approaches showed that a potential new spectral band located between the Landsat-8 Operational Land Imager (OLI) red and …


Beps, Atap, And The New Tax Dialogue: "A Transatlantic Competition?", Reuven Avi-Yonah, Gianluca Mazzoni Sep 2018

Beps, Atap, And The New Tax Dialogue: "A Transatlantic Competition?", Reuven Avi-Yonah, Gianluca Mazzoni

Articles

Since its launch in 2013, the US actively participated in all aspects of the BEPS project. However, until recently, the general view was that following the conclusion of the BEPS negotiations and the change of Administration the US is stepping back from the BEPS process. While the EU was charging ahead with implementing BEPS through the Anti-Tax Avoidance Directive (ATAD), the US stated that it was already in compliance with all BEPS minimum standards and therefore other than Country-by-Country Reporting (CbCR) it had no further BEPS obligations. The US decided not to sign the Multilateral Instrument (MLI) to implement BEPS …


The Rule Of Three, Patrick Barry Sep 2018

The Rule Of Three, Patrick Barry

Articles

Judges use the Rule of Three. Practitioners use the Rule of Three. And so do all manner of legal academics. Yet although many people seem to have an intuitive feel for how useful this rhetorical move is, no extended explanation of its mechanics and variety of forms exists. This essay offers that explanation. It begins with an introduction to the more straightforward form of the rule of three, which simply involves arranging information not in twos or fours or any other set of numbers-but rather in the trusty, melodic structure of threes. It then moves on to a closer look …


Greenhouse Gas Sensors Fabricated With New Materials For Climatic Usage: A Review, Kalathur S.V. Santhanam, Nuzhet Nihaar Nasir Ahamed Aug 2018

Greenhouse Gas Sensors Fabricated With New Materials For Climatic Usage: A Review, Kalathur S.V. Santhanam, Nuzhet Nihaar Nasir Ahamed

Articles

With the increasing utilization of fossil fuels in today’s technological world, the atmosphere’s concentration of greenhouse gases is increasing and needs to be controlled. In order to achieve this goal, it is imperative to have sensors that can provide data on the greenhouse gases in the environment. The recent literature contains a few publications that detail the use of new methods and materials for sensing these gases. The first part of this review is focused on the possible effects of greenhouse gases in the atmosphere, and the second part surveys the developments of sensors for greenhouse gases with coverage on …


Digital Ldo Modelling Techniques For Performance Estimation At Early Design Stage, Haibo Wang, Stefan Leitner Aug 2018

Digital Ldo Modelling Techniques For Performance Estimation At Early Design Stage, Haibo Wang, Stefan Leitner

Articles

This work studies the transient responses and steady-state ripples of digital low dropout (LDO) voltage regulators. Simulation models as well as closed-form expressions are provided for estimating the LDO output settling behaviour after load current or reference voltage changes. Estimation equations for the magnitude and frequency of LDO output steady-state ripples are also presented. The accuracy of the developed models is verified by comparing estimation data with results obtained from circuit simulations. The use of the developed estimation equations in design space exploration is also demonstrated.


Serialised Holography For Brand Protection And Authentication, Dinesh Vather, Izabela Naydenova, Dervil Cody, Monika Zawadzka, Suzanne Martin, Emilia Mihaylova, Stephen Curran, Paul Duffy, Josune Portillo, Daniel Connell, Stephen Mcdonnell, Vincent Toal Aug 2018

Serialised Holography For Brand Protection And Authentication, Dinesh Vather, Izabela Naydenova, Dervil Cody, Monika Zawadzka, Suzanne Martin, Emilia Mihaylova, Stephen Curran, Paul Duffy, Josune Portillo, Daniel Connell, Stephen Mcdonnell, Vincent Toal

Articles

The problems presented by counterfeit products and documentation are discussed. Limitations of existing holograms for anti-counterfeit applications are described. We describe the advantages of full holographic serialisation and the requirements in terms of materials and techniques for mass production of true serialised holograms. These requirements having been met, we report for the first time the mass production of fully serialised holograms. The novelty of approach consists of the direct use of product manufacturer’s information as the object in a holographic recording system along with a self-processing photopolymer and modular optical system to facilitate mass production of truly serialised volume holograms. …


Teaching And Learning Competencies Valued By Engineering Educators: A Pilot Study, Cormac H. Macmahon, Brian Bowe, Orla Mcconnell, Fiona Cranley Jul 2018

Teaching And Learning Competencies Valued By Engineering Educators: A Pilot Study, Cormac H. Macmahon, Brian Bowe, Orla Mcconnell, Fiona Cranley

Articles

At the onset of this paper, it is important to provide context by highlighting two backdrop narratives, which have prompted and guided this research project:-(i) Since 2015, The National Forum for the Enhancement of Teaching & Learning in Ireland has undergone an extensive consultation process on professional development, resulting in a guiding document entitled the National Professional Development Framework (NPDF) for Staff Who Teach in Higher Education [1].(ii) The Technological University Alliance for Dublin has placed Dublin Institute of Technology (DIT), Institute of Technology Blanchardstown (ITB) and Institute of Technology Tallaght (ITT) on a merger trajectory towards technological university designation …


Check Clearing And Voidable Preference Law Under The Bankruptcy Code, David G. Carlson Jul 2018

Check Clearing And Voidable Preference Law Under The Bankruptcy Code, David G. Carlson

Articles

Every business practice must withstand the critique of federal voidable preference law. This article surveys how well check clearing system fares under this adjunct to the principle that unsecured creditors should share equally in a bankruptcy proceeding. Check clearing involves extending short-term credit by depositary banks to their customers. Banks routinely extend unsecured and secured credit. The fate of a bank in its customer's bankruptcy differs, depending on what kind of credit is extended. In the case of an overdraft, banks have preference risk, but they also have powerful defenses to muster against liability. In the case credit is advanced …


Performance Comparison Of Support Vector Machine, Random Forest, And Extreme Learning Machine For Intrusion Detection, Iftikhar Ahmad, Muhammad Javed Iqbal, Mohammad Basheri, Aneel Rahim Jul 2018

Performance Comparison Of Support Vector Machine, Random Forest, And Extreme Learning Machine For Intrusion Detection, Iftikhar Ahmad, Muhammad Javed Iqbal, Mohammad Basheri, Aneel Rahim

Articles

Intrusion detection is a fundamental part of security tools, such as adaptive security appliances, intrusion detection systems, intrusion prevention systems, and firewalls. Various intrusion detection techniques are used, but their performance is an issue. Intrusion detection performance depends on accuracy, which needs to improve to decrease false alarms and to increase the detection rate. To resolve concerns on performance, multilayer perceptron, support vector machine (SVM), and other techniques have been used in recent work. Such techniques indicate limitations and are not efficient for use in large data sets, such as system and network data. The intrusion detection system is used …


Error Sources And Distinctness Of Materials Parameters Obtained By Thz-Time Domain Spectroscopy Using An Example Of Oxidized Engine Oil, Mario Mendez Aller, Ali Mazin Abdul-Munaim, Dennis G. Watson, Sascha Preu Jun 2018

Error Sources And Distinctness Of Materials Parameters Obtained By Thz-Time Domain Spectroscopy Using An Example Of Oxidized Engine Oil, Mario Mendez Aller, Ali Mazin Abdul-Munaim, Dennis G. Watson, Sascha Preu

Articles

Gasoline engine oil (SAE 5W-20) was subjected to thermal oxidization (TO) for four periods of time (0 h, 48 h, 96 h and 144 h) and exposed to THz-time domain spectroscopy (TDS) measurement. Error contributions from various error sources, such as repeatability errors, assembly errors of the probe volume and errors caused by the TDS system were evaluated with respect to discernibility and significance of measurement results. The most significant error source was due to modifications of the TDS setup, causing errors in the range of 0.13% of the refractive index for samples with a refractive index around 1.467 and …


Investigating The Impact Of Internationally Acquired Qualifications On Labour Market Performance: The Case Of Brazil, Charles Alves De Castro Jun 2018

Investigating The Impact Of Internationally Acquired Qualifications On Labour Market Performance: The Case Of Brazil, Charles Alves De Castro

Articles

The aim of this study is to examine the labour market performance of Brazilian students who have acquired international qualifications in the areas of engineering and science. A comprehensive analysis of the literature review demonstrates the importance of international qualifications covering both their benefits and challenges. The gaps found in the literature review are also discussed, as well as the need for a more concrete theoretical framework about the subject. The data used in this research was gathered by semi-structured one-to-one interviews conducted in both person and through telephone. The participants consisted of Brazilian students who have acquired international qualifications …


The States' Interest In Federal Procedure, Diego Zambrano Jun 2018

The States' Interest In Federal Procedure, Diego Zambrano

Articles

No abstract provided.


Strategic Competences For Pricing Quantity Surveying Consultancy Services, Michael Adesi, De-Graft Owusu-Manu, Róisín Murphy Jun 2018

Strategic Competences For Pricing Quantity Surveying Consultancy Services, Michael Adesi, De-Graft Owusu-Manu, Róisín Murphy

Articles

Professional quantity surveying (QS) services are critical to successful delivery of construction projects within planned budget, quality, and duration. The supply of QS professional services is largely dependent on the price level of services and the willingness of clients to pay. The pricing of professional QS consultancy services has been confronted with a myriad of pricing challenges due to rapid changes in the business environment; the pervasive influence of information technology; and the complexity of clients’ expectation. It isthereforenecessary for QS consultancy firms to develop strategic competence for the pricing of their services. In addition, numerous studies have not given …


Developing Polar Networks : Ideas & Possibilities For The Future, Stephen J. Rollins, Daria O. Carle Jun 2018

Developing Polar Networks : Ideas & Possibilities For The Future, Stephen J. Rollins, Daria O. Carle

Articles

Alaska’s geographic location places it at the forefront of research activity and information gathering about the Arctic and the changing environment of the Polar Regions. To facilitate sharing such information with the residents of the state, the Alaska Discovery Portal uses an integrated approach to retrieve materials from for-profit publishers, vetted websites, Alaska’s Digital Archives, open access resources such as the University of Alaska’s Institutional Repository, online topical Research Guides, and more. By licensing resources for all Alaska residents, the Discovery Portal can do what Google and other search engines cannot—pass through pay walls put in place by commercial publishers. …


The Future Of Law And Mobility, Daniel A. Crane Jun 2018

The Future Of Law And Mobility, Daniel A. Crane

Articles

With the launch of the new Journal of Law and Mobility, the University of Michigan is recognizing the transformative impact of new transportation and mobility technologies, from cars, to trucks, to pedestrians, to drones. The coming transition towards intelligent, automated, and connected mobility systems will transform not only the way people and goods move about, but also the way human safety, privacy, and security are protected, cities are organized, machines and people are connected, and the public and private spheres are defined.


Informed Trading And Its Regulation, Merritt B. Fox, Lawrence R. Glosten, Gabriel V. Rauterberg Jun 2018

Informed Trading And Its Regulation, Merritt B. Fox, Lawrence R. Glosten, Gabriel V. Rauterberg

Articles

Informed trading--trading on information not yet reflected in a stock's price-- drives the stock market. Such informational advantages can arise from astute analysis of varied pieces of public news, from just released public information, or from confidential information from inside a firm. We argue that these disparate types of trading are all better regulated as part of the broader phenomenon of informed trading. Informed trading makes share prices more accurate, enhancing the allocation of capital, but also makes markets less liquid, which is costly to the efficiency of trade. Informed trading thus poses a fundamental trade-off in how it affects …


A New Approach To Executory Contracts, John A.E. Pottow Jun 2018

A New Approach To Executory Contracts, John A.E. Pottow

Articles

This Article will proceed as follows. First, it will offer an abbreviated explanation of the treatment of executory contracts under the Code, chronicling the development of the concept of executoriness and the subsequent challenges of its effects. Second, it will explain a new approach that embraces and makes its peace with executoriness by focusing on the proper treatment of non-executory contracts. Third, it will address some of the anticipated counterarguments to the new approach. Finally, it will offer a quick road test to demonstrate how the new approach would have more easily resolved a major litigated precedent in this field.


Multicomponent Analysis Using A Confocal Raman Microscope, Zhengyuan Tang, Sinead J. Barton, Thomas E. Ward, John P. Lowry, Michelle M. Doran, Hugh Byrne, Bryan M. Hennelly Jun 2018

Multicomponent Analysis Using A Confocal Raman Microscope, Zhengyuan Tang, Sinead J. Barton, Thomas E. Ward, John P. Lowry, Michelle M. Doran, Hugh Byrne, Bryan M. Hennelly

Articles

Measuring the concentration of multiple chemical components in a low volume aqueous mixture by Raman spectroscopy has received significant interest in the literature. All of the contributions to date focus on the design of optical systems that facilitate the recording of spectra with high signal-to-noise ratio, by collecting as many Raman scattered photons as possible. In this study, the confocal Raman microscope set-up is investigated for multicomponent analysis. Partial Least Squares Regression is used to quantify physiologically relevant aqueous mixtures of glucose, lactic acid, and urea. The predicted error is 17.81 mg/dL for glucose, 10.6 mg/dL for lactic acid and …


Low Complexity Maximum-Likelihood Detector For Dsttd Architecture Based On The Qrd-M Algorithm, Joaquín Cortez, Miguel Bazdresch, Julio Ramírez, Ramón Palacio, Erica Ruiz May 2018

Low Complexity Maximum-Likelihood Detector For Dsttd Architecture Based On The Qrd-M Algorithm, Joaquín Cortez, Miguel Bazdresch, Julio Ramírez, Ramón Palacio, Erica Ruiz

Articles

This paper presents a new decoder algorithm for the double space-time transmit diversity (DSTTD) system. The decoder is based on the QRD-M algorithm, which performs a breadth-first search of possible solutions tree. The search is simplified by skipping unlikely candididates, and it is stopped when no promising candidates are left. Furthermore, the search is divided into three concurrent iterations, making possible a fast, parallel implementation either in hardware or software. After presenting an analysis of the capacity and diversity of DSTTD, we present performance results showing that the proposed decoder is capable of achieving near maximum likelihood performance. We also …


A Community-Building Framework For Collaborative Research Coordination Across The Education And Biology Research Disciplines, Nancy Pelaez, Trevor R. Anderson, Stephanie M. Gardner, Yue Yin, Joel K. Abraham, Edward L. Bartlett, Cara Gormally, Carol A. Hurney, Tammy M. Long, Dina L. Newman, Karen Sirum, Michael T. Stevens May 2018

A Community-Building Framework For Collaborative Research Coordination Across The Education And Biology Research Disciplines, Nancy Pelaez, Trevor R. Anderson, Stephanie M. Gardner, Yue Yin, Joel K. Abraham, Edward L. Bartlett, Cara Gormally, Carol A. Hurney, Tammy M. Long, Dina L. Newman, Karen Sirum, Michael T. Stevens

Articles

Since 2009, the U.S. National Science Foundation Directorate for Biological Sciences has funded Research Coordination Networks (RCN) aimed at collaborative efforts to improve participation, learning, and assessment in undergraduate biology education (UBE). RCN-UBE projects focus on coordination and communication among scientists and educators who are fostering improved and innovative approaches to biology education. When faculty members collaborate with the overarching goal of advancing undergraduate biology education, there is a need to optimize collaboration between participants in order to deeply integrate the knowledge across disciplinary boundaries. In this essay we propose a novel guiding framework for bringing colleagues together to advance …


Improving Operator Situation Awareness By Phasor Measurement Unit (Pmu) Data Visualization, Esa M. Rantanen, Ernest Fokoue, Jacob Haut, Chandini Ramesh, Kathleen Gegner, Thomas Overbye, Komal Shetye May 2018

Improving Operator Situation Awareness By Phasor Measurement Unit (Pmu) Data Visualization, Esa M. Rantanen, Ernest Fokoue, Jacob Haut, Chandini Ramesh, Kathleen Gegner, Thomas Overbye, Komal Shetye

Articles

The application of phasor measurement unit (PMU) data in the power industry is currently an area of intense interest. The key driver for PMU technology is to use the precise time sources provided by Global Positioning System (GPS) satellites to accurately measure the relative voltage and current phase angles at buses across an interconnect at a very high sampling rate. Presenting PMU data to power system operators in a format that is truly useful for them and that affords improved situation awareness (SA) and fast and accurate decision making is a particular challenge to display design. This report describes development …


Raman Spectral Analysis For Rapid Screening Of Dengue Infection, Tahir Mahmood, Haq Nawaz, A. Ditta, M.I. Majeed, M.A. Hanif, N. Rashid, H.N. Bhatti, H.F. Nargis, M. Saleem, Franck Bonnier, Hugh Byrne May 2018

Raman Spectral Analysis For Rapid Screening Of Dengue Infection, Tahir Mahmood, Haq Nawaz, A. Ditta, M.I. Majeed, M.A. Hanif, N. Rashid, H.N. Bhatti, H.F. Nargis, M. Saleem, Franck Bonnier, Hugh Byrne

Articles

Infection with the dengue virus is currently clinically detected according to different biomarkers in human blood plasma, commonly measured by enzyme linked immunosorbent assays, including non-structural proteins (Ns1), immunoglobulin M (IgM) and immunoglobulin G (IgG). However, there is little or no mutual correlation between the biomarkers, as demonstrated in this study by a comparison of their levels in samples from 17 patients. As an alternative, the label free, rapid screening technique, Raman spectroscopy has been used for the characterisation/diagnosis of healthy and dengue infected human blood plasma samples. In dengue positive samples, changes in specific Raman spectral bands associated with …


Clinical Applications Of Infrared And Raman Spectroscopy: State Of Play And Future Challenges, Matthew Baker, Hugh Byrne, John Chalmers, Peter Gardner, Royston Goodacre, Alex Henderson, Sergei Kazarian, Francis Martin, Julian Moger, Nick Stone, Josep Sule-Suso May 2018

Clinical Applications Of Infrared And Raman Spectroscopy: State Of Play And Future Challenges, Matthew Baker, Hugh Byrne, John Chalmers, Peter Gardner, Royston Goodacre, Alex Henderson, Sergei Kazarian, Francis Martin, Julian Moger, Nick Stone, Josep Sule-Suso

Articles

Vibrational spectroscopies, based on Infrared absorption and/or Raman scattering provide a detailed fingerprint of a material, based on the chemical content. Diagnostic and prognostic tools based on these technologies have the potential to revolutionise our clinical systems leading to improved patient outcome, more efficient public services and significant economic savings. However, despite these strong drivers, there are many fundamental scientific and technological challenges which have limited the implementation of this technology in the clinical arena, although recent years have seen significant progress in addressing these challenges. This review examines (i) the state of the art of clinical applications of infrared …


Emerging Technologies For The Pretreatment Of Lignocellulosic Biomass, Shady S. Hassan, Gwilym Williams, Amit Jaiswal Apr 2018

Emerging Technologies For The Pretreatment Of Lignocellulosic Biomass, Shady S. Hassan, Gwilym Williams, Amit Jaiswal

Articles

Pretreatment of lignocellulosic biomass to overcome its intrinsic recalcitrant nature prior to the production of valuable chemicals has been studied for nearly 200 years. Research has targeted eco-friendly, economical and time-effective solutions, together with a simplified large-scale operational approach. Commonly used pretreatment methods, such as chemical, physico-chemical and biological techniques are still insufficient to meet optimal industrial production requirements in a sustainable way. Recently, advances in applied chemistry approaches conducted under extreme and non-classical conditions has led to possible commercial solutions in the marketplace (e.g. High hydrostatic pressure, High pressure homogenizer, Microwave, Ultrasound technologies). These new industrial technologies are promising …


An Exploratory Study On The Northern Sea Route As An Alternative Shipping Passage, Helene Barenksten Solvang, Stavros Karamperidis, Nikolaos Valantasis Kanellos, Dong Wook Song Apr 2018

An Exploratory Study On The Northern Sea Route As An Alternative Shipping Passage, Helene Barenksten Solvang, Stavros Karamperidis, Nikolaos Valantasis Kanellos, Dong Wook Song

Articles

This qualitative inductive research explores the potential benefits for the Scandinavian economy and ports through the implementation of the Northern Sea Route (NSR) as an alternative for container shipping to the established Southern route through the Suez Canal. To extract expert’s opinions and address these objectives, we utilised in-depth face-to-face semi-structured interviews through purposive sampling in a single case study setting.

The analysis of the data demonstrates that the commercialisation of NSR can yield benefits for the Scandinavian economy (e.g. GDP increase, jobs creation) and reveals the benefits of Scandinavian ports (e.g. ECA’s, flexibility, hinterland, etc.) compared to other ports …


Importance Of Emulsification In Calibrating Infrared Spectroscopes For Analyzing Water Contamination In Used Or In-Service Engine Oil, Torrey Holland, Ali Mazin Abdul-Munaim, Dennis G. Watson, Poopalasingam Sivakumar Apr 2018

Importance Of Emulsification In Calibrating Infrared Spectroscopes For Analyzing Water Contamination In Used Or In-Service Engine Oil, Torrey Holland, Ali Mazin Abdul-Munaim, Dennis G. Watson, Poopalasingam Sivakumar

Articles

Using Fourier transform infrared (FT-IR) spectroscopy we investigated the water content of SAE 15W–40 diesel engine lubricating oil at various levels of contamination to establish instrument calibration standards for measuring water contamination in used or in-service engine oil by the standards of ASTM International. Since some known additives in consumer grade engine oil possess slightly hydrophilic properties, this experiment avoided changing the sample matrix with supplemental additives, such as adding surfactants, to achieve homogeneity of the original sample. The impact of sampling time after contamination on the spectral absorption signature was examined in an attempt to improve the accuracy of …


Enzymatic Extraction Of Fucoxanthin From Brown Seaweeds, Emer Shannon, Nissreen Abu-Ghannam Apr 2018

Enzymatic Extraction Of Fucoxanthin From Brown Seaweeds, Emer Shannon, Nissreen Abu-Ghannam

Articles

Brown seaweeds contain a number of bioactive compounds. The xanthophyll, fucoxanthin, has in vivo efficacy against disorders such as type 2 diabetes, obesity and cancer. Organic solvents are traditionally employed to extract fucoxanthin, but carry a toxic chemical and environmental burden. The aim of this study was to optimise a fucoxanthin extraction method using enzymes, water, low-temperature dehydration and mechanical blending, to produce yields comparable to those achieved with an organic solvent (acetone). Response surface methodology was applied, using Fucus vesiculosus as a model species. A fucoxanthin yield of 0.657 mg g-1 (dry mass) was obtained from F. …


Holographic Beam-Shaping Diffractive Diffusers Fabricated By Using Controlled Laser Speckle, Kevin Murphy, Vincent Toal, Izabela Naydenova, Suzanne Martin Apr 2018

Holographic Beam-Shaping Diffractive Diffusers Fabricated By Using Controlled Laser Speckle, Kevin Murphy, Vincent Toal, Izabela Naydenova, Suzanne Martin

Articles

A method for fabricating diffractive holographic optical diffusers is reported, allowing a high degree of control of the resulting diffuser characteristics. The method consists of recording a laser speckle pattern using a single carrier beam, with controlled speckle size and shape, in an acrylamide-based volume photopolymer. The multiple interferences that create the speckle pattern form the hologram. Results are presented verifying the diffusers are volume holographic in nature and the speckle pattern is recorded accurately in the photopolymer. Diffusers recorded by this method are analysed to characterise the optical performance of the diffusers and to illustrate their beam-shaping capabilities, particularly …