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    12052 research outputs found

    Optimization of SPE and LC-MS/MS methods for the determination of antibiotic concentration in environmental samples

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    In 2015, an estimated 11,134.97 tonnes of antibiotics were consumed by humans in 59 countries. This figure is projected to increase to 128 billion doses by 2030. Antibiotics that are not fully metabolised by the organism end up in wastewater treatment plants. Conventional wastewater treatment plants cannot completely remove antibiotics, which remain in anaerobic treated effluents (ATEs). ATEs themselves lead to the occurrence of antibiotic resistance genes due to their interaction with microbes in treatment facilities. This establishes a clear link between antibiotic use and antibiotic resistance, which causes over 700,000 deaths per year. Thus, it is necessary to accurately measure antibiotic levels in the environment, but the precision of existing methods is limited by the occurrence of matrix effects. Matrix effects are an increase (ion enhancement) or decrease (ion suppression) in the response of the target analyte. Due to this, matrix effects can dramatically alter the performance of an analytical method. The aim of this work was to determine and measure the presence and concentration of antibiotics in water using Solid Phase Liquid Extraction (SPE) and Liquid Chromatography-Mass Spectrometry (LC-MS). SPE was performed using Oasis HLB 200 µg cartridges, and the retained analyte was eluted with acetonitrile and reconstituted in a 10:10:80 methanol:acetonitrile:water solution. LC-MS/MS analysis was completed using an Agilent HPLC instrument with a 1290 Infinity II LC multi-sampler and temperature-regulated sample tray and column compartment. The columns used were a Zorbax eclipse plus C18 2.1 x 50 mm 1.8 μm LC column and a Zorbax eclipse plus C18, 2.1 x 5 mm, 1.8 μm UHPLC guard column at 30 ̊C. A 6470A triple-quadrupole mass spectrometer with electrospray ionisation (Agilent Technologies) was used for detection. Helium was used as a collision gas and N2 as a nebulising and desolvation gas. Data was collected using MassHunter software. The antibiotic sulfamethoxazole (SMX) was detected in each of the investigated surface water bodies in Ireland. The highest detected concentration was 3.2 ng/L showing a matrix effect of 321% (6.33% matrix effect SD). At present, there is no method developed for the detection of antibiotics that is not subjected to inaccuracies due to matrix effects. The developed optimised method allows for the precise and accurate detection of antibiotics in water samples, by decreasing the occurrence of matrix effects to improve sensitivity

    An exploration of pedagogy and creative teaching of the listening component of the Irish post-primary senior music syllabus

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    This thesis investigates teachers’ creative practice in teaching the prescribed repertoire, or “set works” at Leaving Certificate level. To date, little research has been undertaken on this dimension of practice in teaching Music in Post-Primary schools in Ireland. Employing a theoretical framework located in theories of creative learning in general, and creative habits of mind in particular (Lucas, Claxton and Spenser, 2013), teachers’ creative practices in relation to the listening component of the Leaving Certificate Music syllabus were explored, focusing specifically on the study of set works, music analysis, music appreciation and listening skills. Using a sequential, mixed-methods design, the study focuses on how teachers approach the study of set works as one segment of the listening component of the Leaving Certificate Music syllabus. Signature pedagogies (Shulman, 2005) were identified as part of investigation into teaching practice. In particular, the study explores teachers’ attitudes to teaching music analysis, music appreciation and listening skills through a creativity lens. Three overarching questions guide the research: (a) What are Irish music teachers’ perspectives on creativity and creative teaching within Leaving Certificate Music? (b) What distinctive pedagogies are used by Irish Music teachers in teaching musical repertoire? And (c) How do pedagogies practiced reflect teachers’ understanding of and interconnection with creativity? Quantitative findings suggest that teachers are positively disposed towards teaching the set works using creative pedagogies but reported that they felt certain elements of the Leaving Certificate Music syllabus were uncreative and teachers were unsure if they taught the syllabus creatively. Qualitative findings reveal that teachers implement a range of signature pedagogies. Furthermore, they adopt a number of creative approaches and practices, theorised here through a habits of mind framework (Lucas et al., 2013). Such findings illuminate the framework from a music education perspective. Most importantly, the study points to the importance of understanding teachers’ signature and creative pedagogies and how such knowledge can inform future curriculum reform and music teacher professional learning

    Climate Obstruction in Ireland: The Contested Transformation of an Agricultural Economy

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    The Republic of Ireland is considered a climate leader-having passed ambitious climate plans, including the Fossil Fuel Divestment Act (2018)-and a climate laggard, as policy implementation has been weak failing to effectively reduce emissions. This chapter reviews the nuanced landscape of climate obstruction in Ireland describing the evolution of climate policies and outlining the role of news media in platforming climate contrarians as well as climate denial and delay discourses. It also provides a sectoral analysis of climate obstruction paying attention to the energy and transport sectors, and the discursive strategies used by the agri-food sector. This review suggests that transformative change is stymied by the country's long colonial history of economic and ecological exploitation, implementation challenges due to inertia and a long planning process, its reliance on foreign direct investment, and the political power of rural culture and the agri-food sector

    To Join or Not to Join? Understanding the Succession Intentions of Next-generation Family Business Members

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    Looking towards 2030 and beyond, Irish businesses must address the interlocking challenges of transitioning to a low-carbon economy, embracing digital transformation, and absorbing external shocks and higher operational costs resulting from global insecurity. Given their continued prominence in the Irish economy, family businesses will have a leading role to play in remaining strong when faced with the financial uncertainties, and unexpected shocks that these trends will bring. The NCFB led this timely all-island university partnership, recruiting almost 400 next-generation family business students to give the pursuit of succession in turbulent times a contemporary voice. We found that succession aspirations are healthy across the island of Ireland, and the shaping of next-generation intentions regarding educational choices, sustainability, emotional well-being and socio-emotional wealth has a vital role to play in the realisation of these aspirations. With its rich and novel set of findings and recommendations, this report aims to better inform Irish Government and European Union policy positions on family business succession

    Theorising political legitimisation: From stasis to processes

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    Legitimacy remains a key concept in political sociology, and perhaps even more so in lay understandings of political processes and structures, as evidenced by conflict over territories and regimes around the world. However, the concept suffers from a rather static representation, and even when addressed in processual form, in terms of specific moments in the process, such as conditions favouring legitimacy or its effects. Building from an Eliasian perspective, we argue for a more processual concept of legitimisation to encompass the dynamic social networks (figurations) that constitute the more unintentional context for deliberate legitimation claims. As networks expand and intensify, processes of legitimisation incorporate changing and more diverse bases for legitimacy claims, as well as a greater variety of such claims and counterclaims. As the power relations between contending groups change, legitimation practices become part of the integrating functions of the state, shaping figurations and the social habitus

    Effect of Solution Heat Treatment of Nitinol (Ni55%-Ti45%) Manufactured via L-PBF

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    The properties of nitinol, an alloy of nickel and titanium, include its good biocompatibility, corrosion resistance, damping capacity, fatigue strength, superelasticity, and shape memory characteristics. With other conventional methods, it has been challenging to achieve high precision and accuracy of the produced parts; however, laser powder bed fusion (L-PBF) has provided a useful new route for the processing of nitinol. While L-PBF offers many advantages, it also has drawbacks, including the potential for the formation of different phases and residual stress during rapid solidification. Post L-PBF heat treatment conditions aid in the generation of targeted stable phases. As reported by Lee et. al., the mechanical properties and transformation temperatures of the manufactured nitinol samples were largely influenced by the heat treatment. Fan et. al. showed an increase in the transformation temperatures by increasing the heat treatment temperatures after a solution heat treatment. Heat treatments that help in achieving the desired properties are two-step heat treatment processes. This study investigates the feasibility of applying a single-step solution heat treatment to Ni-rich nitinol and reports its effects on density, transformation temperatures, microstructures and microhardness for intended applications

    FRADIS: A Machine Learning-based Multipath Solution for Differentiated Services in a Network Slicing-enhanced Delivery Environment

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    The increase in number of devices per person driven by the latest wearable and IoT devices poses challenges for network support. Despite advancements like IEEE 802.11ax and 5G New Radio, no single technology or provider can handle the growing data surge and diverse service demands. To meet this demand, a programmable and flexible network infrastructure is essential, supporting various technologies and adopting a software-based architecture with open interfaces. A key concepts in achieving this is Network Slicing (NetSli). In this context, the FRAmework for performance-aware Differentiated Innovative Services (FRADIS) was designed as a comprehensive framework for the 5G and beyond heterogeneous network environment, aiming to facilitate the differentiated delivery of services with diverse requirements. FRADIS integrates machine learning to optimize service-specific approaches, choosing between infrastructure-dependent (traffic engineering) and protocol-based solutions. The framework targets a wide range of services, including smart city monitoring, e-health information, emergency messages, infotainment, targeted advertisements, IoT and sensor data, road traffic navigation, agriculture monitoring, and touristic virtual reality. This paper describes the architecture of FRADIS, aiming to achieve traffic control through NetSli at lower network layers, employing a dynamic traffic characteristics-oriented protocol at the transport layer, and using machine learning for adaptive content delivery at the application layer. Preliminary results indicate the benefits of the proposed framework and its flexibility to support multiple types of rich-media applications

    Hierarchical Tree of Deep Networks (HTDN) for Joint Classification of Linear and Non-Linear Modulations

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    Efficient modulation classification remains a key challenge in contemporary communication systems research. In this work, we introduce a novel framework rooted in the principle of divide and conquer to address the complexities associated with jointly classifying linear and nonlinear modulation schemes. Our approach decomposes the classification task into multiple binary problems, effectively leveraging a hierarchical tree-based structure that integrates several low-parameterized CNNs. Simulation results validate the efficacy of our proposed method, demonstrating superior classification performance with a notable reduction in complexity compared to conventional single CNN- based approaches

    Deposition of high-quality, nanoscale SiO2 films and 3D structures

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    Silicon dioxide (SiO2) is ubiquitous in biomedical diagnostics and other applications as a capture medium for nucleic acids and proteins. Diagnostic devices have seen rapid miniaturisation in recent years, due to the increased demand for portable point-of-care diagnostics. However, there are increasing challenges with incorporating SiO2 nanostructures into diagnostic devices, due to the complexity of nanostructured SiO2 synthesis, often involving etching and chemical vapour deposition under high vacuum conditions. We report a novel and straightforward method for deposition of high-quality, nanoscale SiO2 films and 3D SiO2 structures using thermal decomposition of polydimethylsiloxane (PDMS), in a furnace at atmospheric pressure at 500 °C. This method allows individual nanometre controllability of conformal pinhole-free layers on a variety of materials and morphologies. The temperature ramp rate is a key factor in determining the SiO2 deposit morphology, with slower ramp rates leading to highly conformal 2D films and faster ones yielding 3D nanodentrite structures. For the 2D films, the film thickness, as determined by spectroscopic ellipsometry and confirmed by SEM data, is shown to correlate excellently with initial PDMS source material mass in the thickness range 0.8–18 nm. Fits to ellipsometry models confirm that the refractive index of the deposited film matches the expected value for SiO2, while electrical breakdown measurements confirm that the breakdown strength of the films is comparable to that of high-quality thermal oxides. Depositions on high aspect ratio ZnO nanostructures are shown to be highly conformal, leading to core-shell ZnO-SiO2 nanostructures whose shell thickness is in excellent agreement with the expected values from deposition on planar substrates. At faster ramp rates an abrupt morphological transition is seen to a deposit which displays a 3D nanodentrite morphology. The possibilities for applications of both morphologies (and core-shell combinations with other nanostructured materials) in biosensing and related areas are briefly discussed, and the DNA capture capabilities of each nanostructure are measured. The high aspect ratio nanodendrite structures allow for significant DNA capture within microfluidic devices in the presence of low DNA concentrations, with a maximum average capture efficiency of 43.4 % achieved in the presence of 10 ng/mL of DNA, which is an improvement by a factor of ∼ 3 over planar Si surfaces. Improvements by factors of >10 over planar surfaces were achieved at higher DNA concentrations of 100 and 1000 ng/mL

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