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Articles 931 - 960 of 2383

Full-Text Articles in Physical Sciences and Mathematics

A Novel Quantitative Electrochemical Method To Monitor Dna Double-Strand Breaks Caused By A Dna Cleavage Agent At A Dna Sensor, Anna Banasiak, John Cassidy, John Colleran Jan 2018

A Novel Quantitative Electrochemical Method To Monitor Dna Double-Strand Breaks Caused By A Dna Cleavage Agent At A Dna Sensor, Anna Banasiak, John Cassidy, John Colleran

Articles

Biosensors and Bioelectronics, Vol. 117


Comparison Of Fungal Spores Concentrations Measured With Wideband Integrated Bioaerosol Sensor And Hirst Methodology, S. Fernández-Rodríguez, R. Tormo-Molina, N. Lemonis, B. Clot, David O'Connor, John R. Sodeau Jan 2018

Comparison Of Fungal Spores Concentrations Measured With Wideband Integrated Bioaerosol Sensor And Hirst Methodology, S. Fernández-Rodríguez, R. Tormo-Molina, N. Lemonis, B. Clot, David O'Connor, John R. Sodeau

Articles

The aim of this work was to provide both a comparison of traditional and novel methodologies for airborne spores detection (i.e. the Hirst Burkard trap and WIBS-4) and the first quantitative study of airborne fungal concentrations in Payerne (Western Switzerland) as well as their relation to meteorological parameters. From the traditional method -Hirst trap and microscope analysis-, sixty-three propagule types (spores, sporangia and hyphae) were identified and the average spore concentrations measured over the full period amounted to 4145 ± 263.0 spores/m3. Maximum values were reached on July 19th and on August 6th. Twenty-six spore types reached average levels above …


The Janus-Faced Chromophore: A Donor-Acceptor Dyad With Dual Performance In Photon Up-Conversion, Natalia Kiseleva, Mikhail Filatov, Michael Oldenburg, Dimitry Busko, Marius Jakoby, Ian Howard, Bryce Richards, Mathias Senge, Sergey Borisov, Andrey Turshatov Jan 2018

The Janus-Faced Chromophore: A Donor-Acceptor Dyad With Dual Performance In Photon Up-Conversion, Natalia Kiseleva, Mikhail Filatov, Michael Oldenburg, Dimitry Busko, Marius Jakoby, Ian Howard, Bryce Richards, Mathias Senge, Sergey Borisov, Andrey Turshatov

Articles

An electron donor-acceptor dyad based on BODIPY (acceptor) and anthracene (donor) plays either the role of sensitizer or emitter in triplet-triplet annihilation photon up-conversion (TTA-UC). This Janus-like behavior was achieved via altering the relative ordering of charge-transfer and local excited state energies in the dyad through the polarity of TTA-UC media.


Synthesis, Characterisation And Dna Intercalation Studies Of Regioisomers Of Ruthenium (Ii) Polypyridyl Complexes, Laura Perdisatt, Samar Moqadasi, Luke O'Neill, Gary Hessman, Alessandra Ghion, Muhammad Qasim Mushtaq Warraich, Alan Casey, Christine O'Connor Jan 2018

Synthesis, Characterisation And Dna Intercalation Studies Of Regioisomers Of Ruthenium (Ii) Polypyridyl Complexes, Laura Perdisatt, Samar Moqadasi, Luke O'Neill, Gary Hessman, Alessandra Ghion, Muhammad Qasim Mushtaq Warraich, Alan Casey, Christine O'Connor

Articles

Regioisomers of the functional group of the main ligand (L) on a series of [Ru(phen)2L]2+and [Ru(bpy)2L]2+ complexes, where phen is 1,10 phenanthroline and bpy is 2,2′-bipyridine, were synthesised to investigate the interaction with deoxyribonucleic acid (DNA) as potential therapeutics. UV–Vis binding titrations, thermal denaturation and circular dichroism were used to evaluate their interaction with DNA. The conclusions indicated the significance of the auxiliary ligand; especially 1,10-phenanthroline has on the binding constants (Kb). The systematic variation of auxiliary ligand(phen or bpy), and polypyridyl ligand (4-(1H-Imidazo[4,5-f][1,10]phenanthrolin-2-yl)benzonitrile (CPIP), 2-(4-formylphenyl)imidazo[4,5-f] [1,10] phenanthroline (FPIP), 2-(4-bromophenyl)imidazo[4,5-f][1,10]phenanthroline (BPIP) and 2-(4-nitrophenyl)imidazo[4,5-f] [1,10] phenanthroline (NPIP), split in terms of …


A Performance Comparison Of Neural Network And Svm Classifiers Using Eeg Spectral Features To Predict Epileptic Seizures, Ian Thomas Tennant Watson Jan 2018

A Performance Comparison Of Neural Network And Svm Classifiers Using Eeg Spectral Features To Predict Epileptic Seizures, Ian Thomas Tennant Watson

Dissertations

Epilepsy is one of the most common neurological disorders, and afflicts approximately 70 million people globally. 30-40% of patients have refractory epilepsy, where seizures cannot be controlled by anti-epileptic medication, and surgery is neither appropriate, nor available. The unpredictable nature of epileptic seizures is the primary cause of mortality among patients, and leads to significant psychosocial disability. If seizures could be predicted in advance, automatic seizure warning systems could transform the lives of millions of people. This study presents a performance comparison of artificial neural network and sup port vector machine classifiers, using EEG spectral features to predict the onset …


Classification Using Association Rules, Colin Kane Jan 2018

Classification Using Association Rules, Colin Kane

Dissertations

This research investigates the use of an unsupervised learning technique, association rules, to make class predictions. The use of association rules to make class predictions is a growing area of focus within data mining research. The research to date has focused predominately on balanced datasets or synthetized imbalanced datasets. There have been concerns raised that the algorithms using association rules to make classifications do not perform well on imbalanced datasets. This research comprehensively evaluates the accuracy of a number of association rule classifiers in predicting home loan sales in an Irish retail banking context. The experiments designed test three associative …


Automatic Table Extension With Open Data, Benedikt Kleppmann Jan 2018

Automatic Table Extension With Open Data, Benedikt Kleppmann

Dissertations

With thousands of data sources available on the web as well as within organisations, data scientists increasingly spend more time searching for data than analysing it. To ease the task of find and integrating relevant data for data mining projects, this dissertation presents two new methods for automatic table extension. Automatic table extension systems take over the task of tata discovery and data integration by adding new columns with new information (new attributes) to any table. The data values in the new columns are extracted from a given corpus of tables.


Foreword By Guest Editors Maa 2018 Volume 18 Issue 4, Frank Prendergast, A. César González-García, Gary Wells, Juan Antonio Belmonte Jan 2018

Foreword By Guest Editors Maa 2018 Volume 18 Issue 4, Frank Prendergast, A. César González-García, Gary Wells, Juan Antonio Belmonte

Conference Papers

MAA SPECIAL ISSUE VOL 18 ISSUE 4:

Sixty-three (63) Selected (peer reviewed) Papers of the INSAP X – Oxford XI – SEAC 25th Joint Conference ‘ROAD TO THE STARS’, held in Santiago de Compostela, Spain, 18th–22nd September 2017

Mediterranean Archaeology and Archaeometry (MAA) is an Open Access Journal published since 2001 by The University of the Aegean, Department of Mediterranean Studies, Rhodes, Greece.

It covers the dual nature of archaeology and cultural heritage with science which includes, amongst others, natural science applied to archaeology (physics, chemistry, biology, geology, geophysics, astronomy), archaeology, ancient history, cultural sustainability, astronomy in culture, physical anthropology, …


Exploring The Functional And Geometric Bias Of Spatial Relations Using Neural Language Models, Simon Dobnik, Mehdi Ghanimifard, John D. Kelleher Jan 2018

Exploring The Functional And Geometric Bias Of Spatial Relations Using Neural Language Models, Simon Dobnik, Mehdi Ghanimifard, John D. Kelleher

Conference papers

The challenge for computational models of spatial descriptions for situated dialogue systems is the integration of information from different modalities. The semantics of spatial descriptions are grounded in at least two sources of information: (i) a geometric representation of space and (ii) the functional interaction of related objects that. We train several neural language models on descriptions of scenes from a dataset of image captions and examine whether the functional or geometric bias of spatial descriptions reported in the literature is reflected in the estimated perplexity of these models. The results of these experiments have implications for the creation of …


Highly Sensitive Strain Sensor Based On Composite Interference Established Within S-Tapered Multimode Fiber Structure, Ke Tian, Ment Zhang, Gerald Farrell, Ruoning Wang, Elfed Lewis, Pengfei Wang Jan 2018

Highly Sensitive Strain Sensor Based On Composite Interference Established Within S-Tapered Multimode Fiber Structure, Ke Tian, Ment Zhang, Gerald Farrell, Ruoning Wang, Elfed Lewis, Pengfei Wang

Articles

In this paper, a novel strain sensor based on composite interference established within an S-tapered multimode (STM) fiber structure is proposed and experimentally demonstrated. The STM fibre structure is simply realized by non-axially tapering a traditional single-mode-multimode-single-mode (SMS) fiber into S-shape using a fusion splicer. This fabricated S-tapered structure provides an extra Mach-Zehnder interferometer (MZI) that is introduced within the multimode fibre (MMF) section; therefore, composite interference based on the inherent multimode interference (MMI) of an SMS and the introduced MZI is successfully established. This resultant composite interference greatly enhances the performance of traditional SMS fibre structures for strain sensing, …


Whispering Gallery Mode Micro Resonators For Multi-Parameter Applications, Arun Mallik, Gerald Farrell, Manjusha Ramakrishnan, Vishnu Kavungal, Dejun Liu, Qiang Wu Prof. Jan 2018

Whispering Gallery Mode Micro Resonators For Multi-Parameter Applications, Arun Mallik, Gerald Farrell, Manjusha Ramakrishnan, Vishnu Kavungal, Dejun Liu, Qiang Wu Prof.

Articles

A novel fiber optic sensing configuration for simultaneously measuring ammonia vapor (NH3) concentration and relative humidity (RH) in air is proposed and experimentally demonstrated. The system comprised two silica whispering gallery mode (WGM) microsphere resonators coated with different polymer layers. One of the microspheres was dip-coated with sol gel silica polymer and another with a 0.5 % wt./vol. agarose hydrogel. WGMs in both microspheres were excited simultaneously by evanescent coupling using a single adiabatic fiber taper. The optical properties of both coating layers change due to their exposure to ammonia and water molecules in the surrounding atmosphere, resulting in the …


Direct Immunoassays And Their Performance: Theoretical Modelling Of The Effects Of Antibody Orientation And Associated Kinetics, Dana Mackey, Eilis Kelly, Robert Nooney, Richard O'Kennedy Jan 2018

Direct Immunoassays And Their Performance: Theoretical Modelling Of The Effects Of Antibody Orientation And Associated Kinetics, Dana Mackey, Eilis Kelly, Robert Nooney, Richard O'Kennedy

Articles

The orientation and activity of antibodies immobilized on solid surfaces are of direct relevance to many immunosensing applications. We therefore investigate a mathematical model which estimates the fraction of antibodies which are available for reaction in a randomly adsorbed sample. Numerical simulations are presented which highlight the separate effects of antibody orientation, accessibility and loss of binding ability on the amount of captured antigen. The assay response can then be expressed as a function of total antibody density and used for optimizing the surface coverage strategy under various conditions.


Review: The Use Of Real-Time Fluorescence Instrumentation To Monitor Ambient Primary Biological Aerosol Particles (Pbap), Gavin Sewell, David O'Connor, Michael J. Fennelly, Michael B. Prentice, John R. Sodeau Jan 2018

Review: The Use Of Real-Time Fluorescence Instrumentation To Monitor Ambient Primary Biological Aerosol Particles (Pbap), Gavin Sewell, David O'Connor, Michael J. Fennelly, Michael B. Prentice, John R. Sodeau

Articles

Primary biological aerosol particles (PBAP) encompass many particle types that are derived from several biological kingdoms. These aerosol particles can be composed of both whole living units such as pollen, bacteria, and fungi, as well as from mechanically formed particles, such as plant debris. They constitute a significant proportion of the overall atmospheric particle load and have been linked with adverse health issues and climatic effects on the environment. Traditional methods for their analysis have focused on the direct capture of PBAP before subsequent laboratory analysis. These analysis types have generally relied on direct optical microscopy or incubation on agar …


Advances In Switchable And Highly Insulating Autonomous (Self-Powered) Glazing Systems For Adaptive Low Energy Buildings, Aritra Ghosh, Brian Norton Jan 2018

Advances In Switchable And Highly Insulating Autonomous (Self-Powered) Glazing Systems For Adaptive Low Energy Buildings, Aritra Ghosh, Brian Norton

Articles

Building energy reduction requires highly advanced low heat loss, heat gain and comfortable daylight allowing glazing. Presently available glazing systems are classified mainly in two categories, controlling solar heat gain and controlling low heat loss. Low heat loss through glazing systems can be achieved by (i) suppression of convection in the air between the outer panes by use of multiple glass panes or aerogels, (ii) having an inert gas or vacuum between the panes to reduce or eliminate respectively convective heat transfer. In all these systems, low emissivity coatings are also required to reduce the radiative heat transfer. Low heat …


Solar Alignment And The Irish Passage Tomb Tradition, Frank Prendergast Jan 2018

Solar Alignment And The Irish Passage Tomb Tradition, Frank Prendergast

Book/Book Chapter

A succinct and very useful, illustrated, explanatory guide to the phenomenon of solar alignment in the irish Passage Tomb tradition. Includes a listing of where to visit the 15 known astronomically aligned passage tombs in the 32 counties.

Written by Dr Frank Prendergast who is now Emeritus at the Dublin Institute of Technology, where he researches Irish prehistoric monuments and their landscapes from a cultural astronomy perspective. His current interests and publications are on the meaning of the dark sky in the prehistoric past and on the conservation of archaeological landscapes from light pollution.

Heritage Guides are included free with …


Dynamical Analysis Of An N−H−T Cosmological Quintessence Real Gas Model With A General Equation Of State, Emil Prodanov, Rossen Ivanov Jan 2018

Dynamical Analysis Of An N−H−T Cosmological Quintessence Real Gas Model With A General Equation Of State, Emil Prodanov, Rossen Ivanov

Articles

The cosmological dynamics of a quintessence model based on real gas with general equation of state is presented within the framework of a three-dimensional dynamical system describing the time evolution of the number density, the Hubble parameter, and the temperature. Two global first integrals are found and examples for gas with virial expansion and van der Waals gas are presented. The van der Waals system is completely integrable. In addition to the unbounded trajectories, stemming from the presence of the conserved quantities, stable periodic solutions (closed orbits) also exist under certain conditions and these represent models of a cyclic Universe. …


Distribution Of Zeros Of Nondegenerate Functions On Short Cuttings Ii, Vasili Ivanovich Bernik, Natalia Viktorovna Budarina, Artyom Vadimovich Lunevich, Hugh O’Donnell Jan 2018

Distribution Of Zeros Of Nondegenerate Functions On Short Cuttings Ii, Vasili Ivanovich Bernik, Natalia Viktorovna Budarina, Artyom Vadimovich Lunevich, Hugh O’Donnell

Articles

No abstract provided.


Catalogue Of Extreme Wave Events In Ireland: Revised And Updated For 14 680 Bp To 2017, Laura Cooke, Emiliano Renzi, John M. Dudley, Colm Clancy, FréDéRic Dias Jan 2018

Catalogue Of Extreme Wave Events In Ireland: Revised And Updated For 14 680 Bp To 2017, Laura Cooke, Emiliano Renzi, John M. Dudley, Colm Clancy, FréDéRic Dias

Articles

This paper aims to extend and update the survey of extreme wave events in Ireland that was previously carried out by O’Brien et al. (2013). The original catalogue high- lighted the frequency of such events dating back as far as the turn of the last ice age and as recent as 2012. Ireland’s marine territory extends far beyond its coastline and is one of the largest seabed territories in Europe. It is therefore not surprising that extreme waves have continued to occur reg- ularly since 2012, particularly considering the severity of weather during the winters of 2013–2014 and 2015–2016. In …


Reply To "Comment On 'Cyclic Universe With An Inflationary Phase From A Cosmological Model With Real Gas Quintessence"', Rossen Ivanov, Emil Prodanov Jan 2018

Reply To "Comment On 'Cyclic Universe With An Inflationary Phase From A Cosmological Model With Real Gas Quintessence"', Rossen Ivanov, Emil Prodanov

Articles

No abstract provided.


“Woodlands” - A Virtual Reality Serious Game Supporting Learning Of Practical Road Safety Skills., Krzysztof Szczurowski, Matt Smith Jan 2018

“Woodlands” - A Virtual Reality Serious Game Supporting Learning Of Practical Road Safety Skills., Krzysztof Szczurowski, Matt Smith

Conference Papers

In developed societies road safety skills are taught early and often practiced under the supervision of a parent, providing children with a combination of theoretical and practical knowledge. At some point children will attempt to cross a road unsupervised, at that point in time their safety depends on the effectiveness of their road safety education. To date, various attempts to supplement road safety education with technology were made. Most common approach focus on addressing declarative knowledge, by delivering road safety theory in an engaging fashion. Apart from expanding on text based resources to include instructional videos and animations, some stakeholders …


Environmental Impact Assessment Of Pinaceae Airborne Pollen And Green Infrastructure Using Bim, Santiago Fernández-Rodríguez, Juan Pedro Cortés-Pérez, Paloma Prieto Muriel, Rafael Tormo-Molina, J. M. Maya-Manzano Jan 2018

Environmental Impact Assessment Of Pinaceae Airborne Pollen And Green Infrastructure Using Bim, Santiago Fernández-Rodríguez, Juan Pedro Cortés-Pérez, Paloma Prieto Muriel, Rafael Tormo-Molina, J. M. Maya-Manzano

Articles

Urban air quality is a parameter that plays a major role in human health at the local scale. Consequently, in urban planning, the behavior and potential risk of allergenicity for some pollen grains coming from ornamental trees and green spaces surrounding newly built buildings, should be considered. This paper aims to study how pollen exposure, influenced by weather parameters, can be assessed and integrated in the designing and building of constructions as other component of air quality assessment beforehand, by using BIM. Based on a comparative aerobiological study at the height over a building (sampled by two traps at ground …


Robust, Bridge-Less Ion-Selective Electrodes With Significantly Reduced Need For Pre- And Post-Application Handling, Benjamin Schazmann, S. Demey, Z. Waqar Ali, M-S Plissart, E. Brennan, A. Radu Jan 2018

Robust, Bridge-Less Ion-Selective Electrodes With Significantly Reduced Need For Pre- And Post-Application Handling, Benjamin Schazmann, S. Demey, Z. Waqar Ali, M-S Plissart, E. Brennan, A. Radu

Articles

We are demonstrating robust, single-layer ion-selective electrode (ISE) utilizing simple Ag/AgCl electrode as solid support without the need for intermediate polymer layer. We have created and chemically linked a family of imidazolium ionic liquids (ILs) with poly (vinyl chloride) (PVC) using click chemistry, resulting in hybrid materials with tunable characteristics. The resultant material inherently contains chloride ion thus offering the ability to stabilize interfacial potential. This allowed us to construct very simple, single-layer membranes with significantly reduced need for conditioning as an added bonus compared to traditional sensors. Chemical immobilization of ISE membrane components also led to extended lifetime as …


An Analysis Of Software Testing Practices On Migrations From On Premise To Cloud Hosted Environments, Ronan Mullen Jan 2018

An Analysis Of Software Testing Practices On Migrations From On Premise To Cloud Hosted Environments, Ronan Mullen

Dissertations

This research project examines the differences between software testing practices that are carried out on software that is installed locally (i.e. on premise) versus software that has migrated to a cloud hosted environment. In conjunction with this, focus was placed on determining what methodologies and frameworks are in existence for assisting with software migrations to the cloud. The reason for carrying out this research project was that the transition to cloud computing is becoming more and more mainstream, as a result organisations are required to focus their efforts on how best to move their software to the cloud while ensuring …


Comparing The Effectiveness Of Support Vector Machines And Convolutional Neural Networks For Determining User Intent In Conversational Agents, Kieran O Sullivan Jan 2018

Comparing The Effectiveness Of Support Vector Machines And Convolutional Neural Networks For Determining User Intent In Conversational Agents, Kieran O Sullivan

Dissertations

Over the last fifty years, conversational agent systems have evolved in their ability to understand natural language input. In recent years Natural Language Processing (NLP) and Machine Learning (ML) have allowed computer systems to make great strides in the area of natural language understanding. However, little research has been carried out in these areas within the context of conversational systems. This paper identifies Convolutional Neural Network (CNN) and Support Vector Machine (SVM) as the two ML algorithms with the best record of performance in ex isting NLP literature, with CNN indicated as generating the better results of the two. A …


Using Machine Learning Techniques To Predict A Risk Score For New Members Of A Chit Fund Group, Sinead Aherne Jan 2018

Using Machine Learning Techniques To Predict A Risk Score For New Members Of A Chit Fund Group, Sinead Aherne

Dissertations

Predicting the risk score of new and potential customers is used across the financial industry. By implementing the prediction of risk scores for their customers a chit fund company can improve the knowledge and customer understanding without relying on human knowledge. Data is collected on each customer before they have taken out credit and during the time they contribute to a chit fund. Having collected the necessary data, the company can then decide whether modelling customer risk would benefit them. As the data is available historically, one aspect of risk score prediction will be the focus of this thesis, supervised …


Through The Net: Investigating How User Characteristics Influence Susceptibility To Phishing, Charlie Marriott Jan 2018

Through The Net: Investigating How User Characteristics Influence Susceptibility To Phishing, Charlie Marriott

Dissertations

In the past 25 years, the internet has grown and evolved from a niche networking technology, used almost exclusively by researchers and enthusiasts, into the driving force of modern economies. Fraud has evolved too, with rates of cybercrime on the increase as criminals become increasingly sophisticated in using technology to deceive their victims. The world is an online place, and data is the new oil. Phishing is a form of social engineering that is not that different from traditional fraud. Phishing attackers try to trick their victims into revealing valuable private information, usually for financial gain, by posing as a …


Automation Of Authorisation Vulnerability Detection In Authenticated Web Applications, Niall Caffrey Jan 2018

Automation Of Authorisation Vulnerability Detection In Authenticated Web Applications, Niall Caffrey

Dissertations

In the beginning the World Wide Web, also known as the Internet, consisted mainly of websites. These were essentially information depositories containing static pages, with the flow of information mostly one directional, from the server to the user’s browser. Most of these websites didn’t authenticate users, instead, each user was treated the same, and presented with the same information. A malicious party that gained access to the web server hosting these websites would usually not gain access to confidential information as most of the information on the web server would already be accessible to the public. Instead, the malicious party …


Assesing Completeness Of Solvency And Financial Condition Reports Through The Use Of Machine Learning And Text Classification, Ruairí Nugent Jan 2018

Assesing Completeness Of Solvency And Financial Condition Reports Through The Use Of Machine Learning And Text Classification, Ruairí Nugent

Dissertations

Text mining is a method for extracting useful information from unstructured data through the identification and exploration of large amounts of text. It is a valuable support tool for organisations. It enables a greater understanding and identification of relevant business insights from text. Critically it identifies connections between information within texts that would otherwise go unnoticed. Its application is prevalent in areas such as marketing and political science however, until recently it has been largely overlooked within economics. Central banks are beginning to investigate the benefits of machine learning, sentiment analysis and natural language processing in light of the large …


Augmented Reality As A Potential Tool For Filmmaking, Paul Blachfield Jan 2018

Augmented Reality As A Potential Tool For Filmmaking, Paul Blachfield

Dissertations

Augmented Reality (AR) has been used for a wide variety of industries. The purpose of this study was to determine the suitability of this technology for use in filmmaking. One of the problems on a film set is the time taken to block a scene. Blocking involves the placement of subjects and props within a scene. Different ideas have been used for blocking including previzualisation and Virtual Reality (VR). This study proposesed the use of AR as a tool to solve this problem. Marker-based and Markerless AR were assessed in turn to determine their suitability for addressing the problem. The …


An Exploration Of Parliamentary Speeches In The Irish Parliament Using Topic Modeling, Fiona Leheny Jan 2018

An Exploration Of Parliamentary Speeches In The Irish Parliament Using Topic Modeling, Fiona Leheny

Dissertations

The only resource available in the public domain which highlights parliamentary ac tivity is parliamentary questions. Up until the last ten years, manual content analysis was carried out to classify these. More recently, machine learning techniques have been used to automatically classify and analyse these data sets. This study analyses the verbal parliamentary speeches in the Irish Parliament (known as the D´ail) over a ten year period using unsupervised machine learning. It does so by applying a less utilised topic modeling technique, known as Non-negative Matrix Factorisation (NMF), to de tect the latent themes in these speeches. A two-layer dynamic …