10,810 research outputs found

    Covid-19 and Capitalism

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    This open access book provides a comprehensive analysis of the socioeconomic determinants of Covid-19. From the end of 2019 until presently, the world has been ravaged by the Covid-19 pandemic. Although the cause of this is (obviously) a virus, the extent to which this virus spread, and therefore the number of infections and deaths, was largely determined by socio-economic factors. From this, it follows that the course of the pandemic varies greatly from one country to another. This observation applies both to countries’ resilience to such a pandemic (which is mainly rooted in the period preceding the outbreak of the virus) and to the way in which countries have reacted to the virus (including the political choices on how to respond). Meanwhile, research has made it clear that the nature of this response (e.g., elimination policy, mitigation policy, and proceeding herd immunity) was, on the one hand, strongly determined by political and ideological factors and, on the other hand, was highly influential in the factors of success or failure in combating the pandemic. The book focuses on the situation in a number of Western regions (notably the USA, the UK, and the EU and its Member States). The author addresses the reasons why in many Western countries both pandemic prevention and response policies to Covid-19 have failed. The book concludes with recommendations concerning the rearrangement of the socio-economic order that could increase the resilience of (Western) societies against such pandemics

    Resource Recovery from Water

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    Throughout history, the first and foremost role of urban water management has been the protection of human health and the local aquatic environment. To this end, the practice of (waste-)water treatment has maintained a central focus on the removal of pollutants through dissipative pathways. Approaches like – in the case of wastewater treatment – the activated sludge process, which makes ‘hazardous things’ disappear, have benefitted our society tremendously by safeguarding human and environmental health. While conventional (waste-)water treatment is regarded as one of the greatest engineering achievements of the 20th century, these dissipative approaches will not suffice in the 21st century as we enter the era of the circular economy. A key challenge for the future of urban water management is the need to re-envision the role of water infrastructure, still holding paramount the safeguard of human and environmental health while also becoming a more proactive force for sustainable development through the recovery of resources embedded in urban water. This book aims (i) to explain the basic principles governing resource recovery from water (how much is there, really); (ii) to provide a comprehensive overview and critical assessment of the established and emerging technologies for resource recovery from water; and (iii) to put resource recovery from water in a legal, economic (including the economy of scale of recovered products), social (consumer's point of view), and environmental sustainability framework. This book serves as a powerful teaching tool at the graduate entry master level with an aim to help develop the next generation of engineers and experts and is also highly relevant for seasoned water professionals and practicing engineers

    New Research and Trends in Higher Education

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    This book aims to discuss new research and trends on all dimensions of Higher Education, as there is a growing interest in the field of Higher Education, regarding new methodologies, contexts, and technologies. It includes investigations of diverse issues that affect the learning processes in Higher Education: innovations in learning, new pedagogical methods, and new learning contexts.In this sense, original research contributions of research papers, case studies and demonstrations that present original scientific results, methodological aspects, concepts and educational technologies, on the following topics:a) Technological Developments in Higher Education: mobile technology, virtual environments, augmented reality, automation and robotics, and other tools for universal learning, focusing on issues that are not addressed by existing research;b) Digital Higher Education: mobile learning, eLearning, Game-based Learning, social media in education, new learning models and technologies and wearable technologies for education;c) Case Studies in Higher Education: empirical studies in higher education regarding digital technologies, new methodologies, new evaluation techniques and tools, perceptions of learning processes efficiency and digital learning best practice

    Paradox Role of Oxidative Stress in Cancer

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    Reactive oxygen species (ROS) are produced by healthy cells and are maintained at physiological levels by antioxidant systems. However, when ROS increase in number, a condition of oxidative stress occurs, leading to many human diseases, including cancer. The relationship between oxidative stress and cancer is complex since ROS play a double-edged role in cancer development and under therapy response. This paradox represents a great challenge for researchers and needs to be investigated. The articles collected in this Special Issue can help to clarify the role of ROS modulation in cancer prevention and treatment, and to dissect the molecular mechanisms underlying its paradoxical role in order to counteract carcinogenesis or enhance sensitivity to anticancer therapy

    RNA pull-down-confocal nanoscanning (RP-CONA), a novel method for studying RNA/protein interactions in cell extracts that detected potential drugs for Parkinson’s disease targeting RNA/HuR complexes

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    MicroRNAs (miRNAs, miRs) are a class of small non-coding RNAs that regulate gene expression through specific base-pair targeting. The functional mature miRNAs usually undergo a two-step cleavage from primary miRNAs (pri-miRs), then precursor miRNAs (pre-miRs). The biogenesis of miRNAs is tightly controlled by different RNA-binding proteins (RBPs). The dysregulation of miRNAs is closely related to a plethora of diseases. Targeting miRNA biogenesis is becoming a promising therapeutic strategy. HuR and MSI2 are both RBPs. MiR-7 is post-transcriptionally inhibited by the HuR/MSI2 complex, through a direct interaction between HuR and the conserved terminal loop (CTL) of pri-miR-7-1. Small molecules dissociating pri-miR-7/HuR interaction may induce miR-7 production. Importantly, the miR-7 levels are negatively correlated with Parkinson’s disease (PD). PD is a common, incurable neurodegenerative disease causing serious motor deficits. A hallmark of PD is the presence of Lewy bodies in the human brain, which are inclusion bodies mainly composed of an aberrantly aggregated protein named α-synuclein (α-syn). Decreasing α-syn levels or preventing α-syn aggregation are under investigation as PD treatments. Notably, α-syn is negatively regulated by several miRNAs, including miR-7, miR-153, miR-133b and others. One hypothesis is that elevating these miRNA levels can inhibit α-syn expression and ameliorate PD pathologies. In this project, we identified miR-7 as the most effective α-syn inhibitor, among the miRNAs that are downregulated in PD, and with α-syn targeting potentials. We also observed potential post-transcriptional inhibition on miR-153 biogenesis in neuroblastoma, which may help to uncover novel therapeutic targets towards PD. To identify miR-7 inducers that benefit PD treatment by repressing α-syn expression, we developed a novel technique RNA Pull-down Confocal Nanoscaning (RP-CONA) to monitor the binding events between pri-miR-7 and HuR. By attaching FITC-pri-miR-7-1-CTL-biotin to streptavidin-coated agarose beads and incubating them in human cultured cell lysates containing overexpressed mCherry-HuR, the bound RNA and protein can be visualised as quantifiable fluorescent rings in corresponding channels in a confocal high-content image system. A pri-miR-7/HuR inhibitor can decrease the relative mCherry/FITC intensity ratio in RP-CONA. With this technique, we performed several small-scale screenings and identified that a bioflavonoid, quercetin can largely dissociate the pri-miR-7/HuR interaction. Further studies proved that quercetin was an effective miR-7 inducer as well as α-syn inhibitor in HeLa cells. To understand the mechanism of quercetin mediated α-syn inhibition, we tested the effects of quercetin treatment with miR-7-1 and HuR knockout HeLa cells. We found that HuR was essential in this pathway, while miR-7 hardly contributed to the α-syn inhibition. HuR can directly bind an AU-rich element (ARE) at the 3’ untranslated region (3’-UTR) of α-syn mRNA and promote translation. We believe quercetin mainly disrupts the ARE/HuR interaction and disables the HuR-induced α-syn expression. In conclusion, we developed and optimised RP-CONA, an on-bead, lysate-based technique detecting RNA/protein interactions, as well as identifying RNA/protein modulators. With RP-CONA, we found quercetin inducing miR-7 biogenesis, and inhibiting α-syn expression. With these beneficial effects, quercetin has great potential to be applied in the clinic of PD treatment. Finally, RP-CONA can be used in many other RNA/protein interactions studies

    EcologĂ­a microbiana del Salar de Uyuni (Bolivia). Efectos de la caotropicidad como factor limitante para la vida

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    Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 10-01-2022Este trabajo se ha llevado a cabo mediante financiación concedida por los siguientes organismos: Comunidad de Madrid y Fondo Social Europeo (PEJ-2017-AI/AMB-6229), Ministerio de Ciencia, Innovación y Universidades (CGL2015-66242-R y PID2019-10481266GB-I00) y Programa Erasmus+ 2019/202

    Examining the Impact of Personal Social Media Use at Work on Workplace Outcomes

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    A noticable shift is underway in today’s multi-generational workforce. As younger employees propel digital workforce transformation and embrace technology adoption in the workplace, organisations need to show they are forward-thinking in their digital transformation strategies, and the emergent integration of social media in organisations is reshaping internal communication strategies, in a bid to improve corporate reputations and foster employee engagement. However, the impact of personal social media use on psychological and behavioural workplace outcomes is still debatebale with contrasting results in the literature identifying both positive and negative effects on workplace outcomes among organisational employees. This study seeks to examine this debate through the lens of social capital theory and study personal social media use at work using distinct variables of social use, cognitive use, and hedonic use. A quantitative analysis of data from 419 organisational employees in Jordan using SEM-PLS reveals that personal social media use at work is a double-edged sword as its impact differs by usage types. First, the social use of personal social media at work reduces job burnout, turnover intention, presenteeism, and absenteeism; it also increases job involvement and organisational citizen behaviour. Second, the cognitive use of personal social media at work increases job involvement, organisational citizen behaviour, employee adaptability, and decreases presenteeism and absenteeism; it also increases job burnout and turnover intention. Finally, the hedonic use of personal social media at work carries only negative effects by increasing job burnout and turnover intention. This study contributes to managerial understanding by showing the impact of different types of personal social media usage and recommends that organisations not limit employee access to personal social media within work time, but rather focus on raising awareness of the negative effects of excessive usage on employee well-being and encourage low to moderate use of personal social media at work and other personal and work-related online interaction associated with positive workplace outcomes. It also clarifies the need for further research in regions such as the Middle East with distinct cultural and socio-economic contexts

    FiabilitĂ© de l’underfill et estimation de la durĂ©e de vie d’assemblages microĂ©lectroniques

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    Abstract : In order to protect the interconnections in flip-chip packages, an underfill material layer is used to fill the volumes and provide mechanical support between the silicon chip and the substrate. Due to the chip corner geometry and the mismatch of coefficient of thermal expansion (CTE), the underfill suffers from a stress concentration at the chip corners when the temperature is lower than the curing temperature. This stress concentration leads to subsequent mechanical failures in flip-chip packages, such as chip-underfill interfacial delamination and underfill cracking. Local stresses and strains are the most important parameters for understanding the mechanism of underfill failures. As a result, the industry currently relies on the finite element method (FEM) to calculate the stress components, but the FEM may not be accurate enough compared to the actual stresses in underfill. FEM simulations require a careful consideration of important geometrical details and material properties. This thesis proposes a modeling approach that can accurately estimate the underfill delamination areas and crack trajectories, with the following three objectives. The first objective was to develop an experimental technique capable of measuring underfill deformations around the chip corner region. This technique combined confocal microscopy and the digital image correlation (DIC) method to enable tri-dimensional strain measurements at different temperatures, and was named the confocal-DIC technique. This techique was first validated by a theoretical analysis on thermal strains. In a test component similar to a flip-chip package, the strain distribution obtained by the FEM model was in good agreement with the results measured by the confocal-DIC technique, with relative errors less than 20% at chip corners. Then, the second objective was to measure the strain near a crack in underfills. Artificial cracks with lengths of 160 ÎŒm and 640 ÎŒm were fabricated from the chip corner along the 45° diagonal direction. The confocal-DIC-measured maximum hoop strains and first principal strains were located at the crack front area for both the 160 ÎŒm and 640 ÎŒm cracks. A crack model was developed using the extended finite element method (XFEM), and the strain distribution in the simulation had the same trend as the experimental results. The distribution of hoop strains were in good agreement with the measured values, when the model element size was smaller than 22 ÎŒm to capture the strong strain gradient near the crack tip. The third objective was to propose a modeling approach for underfill delamination and cracking with the effects of manufacturing variables. A deep thermal cycling test was performed on 13 test cells to obtain the reference chip-underfill delamination areas and crack profiles. An artificial neural network (ANN) was trained to relate the effects of manufacturing variables and the number of cycles to first delamination of each cell. The predicted numbers of cycles for all 6 cells in the test dataset were located in the intervals of experimental observations. The growth of delamination was carried out on FEM by evaluating the strain energy amplitude at the interface elements between the chip and underfill. For 5 out of 6 cells in validation, the delamination growth model was consistent with the experimental observations. The cracks in bulk underfill were modelled by XFEM without predefined paths. The directions of edge cracks were in good agreement with the experimental observations, with an error of less than 2.5°. This approach met the goal of the thesis of estimating the underfill initial delamination, areas of delamination and crack paths in actual industrial flip-chip assemblies.Afin de protĂ©ger les interconnexions dans les assemblages, une couche de matĂ©riau d’underfill est utilisĂ©e pour remplir le volume et fournir un support mĂ©canique entre la puce de silicium et le substrat. En raison de la gĂ©omĂ©trie du coin de puce et de l’écart du coefficient de dilatation thermique (CTE), l’underfill souffre d’une concentration de contraintes dans les coins lorsque la tempĂ©rature est infĂ©rieure Ă  la tempĂ©rature de cuisson. Cette concentration de contraintes conduit Ă  des dĂ©faillances mĂ©caniques dans les encapsulations de flip-chip, telles que la dĂ©lamination interfaciale puce-underfill et la fissuration d’underfill. Les contraintes et dĂ©formations locales sont les paramĂštres les plus importants pour comprendre le mĂ©canisme des ruptures de l’underfill. En consĂ©quent, l’industrie utilise actuellement la mĂ©thode des Ă©lĂ©ments finis (EF) pour calculer les composantes de la contrainte, qui ne sont pas assez prĂ©cises par rapport aux contraintes actuelles dans l’underfill. Ces simulations nĂ©cessitent un examen minutieux de dĂ©tails gĂ©omĂ©triques importants et des propriĂ©tĂ©s des matĂ©riaux. Cette thĂšse vise Ă  proposer une approche de modĂ©lisation permettant d’estimer avec prĂ©cision les zones de dĂ©lamination et les trajectoires des fissures dans l’underfill, avec les trois objectifs suivants. Le premier objectif est de mettre au point une technique expĂ©rimentale capable de mesurer la dĂ©formation de l’underfill dans la rĂ©gion du coin de puce. Cette technique, combine la microscopie confocale et la mĂ©thode de corrĂ©lation des images numĂ©riques (DIC) pour permettre des mesures tridimensionnelles des dĂ©formations Ă  diffĂ©rentes tempĂ©ratures, et a Ă©tĂ© nommĂ©e le technique confocale-DIC. Cette technique a d’abord Ă©tĂ© validĂ©e par une analyse thĂ©orique en dĂ©formation thermique. Dans un Ă©chantillon similaire Ă  un flip-chip, la distribution de la dĂ©formation obtenues par le modĂšle EF Ă©tait en bon accord avec les rĂ©sultats de la technique confocal-DIC, avec des erreurs relatives infĂ©rieures Ă  20% au coin de puce. Ensuite, le second objectif est de mesurer la dĂ©formation autour d’une fissure dans l’underfill. Des fissures artificielles d’une longueuer de 160 ÎŒm et 640 ÎŒm ont Ă©tĂ© fabriquĂ©es dans l’underfill vers la direction diagonale de 45°. Les dĂ©formations circonfĂ©rentielles maximales et principale maximale Ă©taient situĂ©es aux pointes des fissures correspondantes. Un modĂšle de fissure a Ă©tĂ© dĂ©veloppĂ© en utilisant la mĂ©thode des Ă©lĂ©ments finis Ă©tendue (XFEM), et la distribution des contraintes dans la simuation a montrĂ© la mĂȘme tendance que les rĂ©sultats expĂ©rimentaux. La distribution des dĂ©formations circonfĂ©rentielles maximales Ă©tait en bon accord avec les valeurs mesurĂ©es lorsque la taille des Ă©lĂ©ments Ă©tait plus petite que 22 ÎŒm, assez petit pour capturer le grand gradient de dĂ©formation prĂšs de la pointe de fissure. Le troisiĂšme objectif Ă©tait d’apporter une approche de modĂ©lisation de la dĂ©lamination et de la fissuration de l’underfill avec les effets des variables de fabrication. Un test de cyclage thermique a d’abord Ă©tĂ© effectuĂ© sur 13 cellules pour obtenir les zones dĂ©laminĂ©es entre la puce et l’underfill, et les profils de fissures dans l’underfill, comme rĂ©fĂ©rence. Un rĂ©seau neuronal artificiel (ANN) a Ă©tĂ© formĂ© pour Ă©tablir une liaison entre les effets des variables de fabrication et le nombre de cycles Ă  la dĂ©lamination pour chaque cellule. Les nombres de cycles prĂ©dits pour les 6 cellules de l’ensemble de test Ă©taient situĂ©s dans les intervalles d’observations expĂ©rimentaux. La croissance de la dĂ©lamination a Ă©tĂ© rĂ©alisĂ©e par l’EF en Ă©valuant l’énergie de la dĂ©formation au niveau des Ă©lĂ©ments interfaciaux entre la puce et l’underfill. Pour 5 des 6 cellules de la validation, le modĂšle de croissance du dĂ©laminage Ă©tait conforme aux observations expĂ©rimentales. Les fissures dans l’underfill ont Ă©tĂ© modĂ©lisĂ©es par XFEM sans chemins prĂ©dĂ©finis. Les directions des fissures de bord Ă©taient en bon accord avec les observations expĂ©rimentales, avec une erreur infĂ©rieure Ă  2,5°. Cette approche a rĂ©pondu Ă  la problĂ©matique qui consiste Ă  estimer l’initiation des dĂ©lamination, les zones de dĂ©lamination et les trajectoires de fissures dans l’underfill pour des flip-chips industriels

    Synthesis and Characterisation of Low-cost Biopolymeric/mineral Composite Systems and Evaluation of their Potential Application for Heavy Metal Removal

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    Heavy metal pollution and waste management are two major environmental problems faced in the world today. Anthropogenic sources of heavy metals, especially effluent from industries, are serious environmental and health concerns by polluting surface and ground waters. Similarly, on a global scale, thousands of tonnes of industrial and agricultural waste are discarded into the environment annually. There are several conventional methods to treat industrial effluents, including reverse osmosis, oxidation, filtration, flotation, chemical precipitation, ion exchange resins and adsorption. Among them, adsorption and ion exchange are known to be effective mechanisms for removing heavy metal pollution, especially if low-cost materials can be used. This thesis was a study into materials that can be used to remove heavy metals from water using low-cost feedstock materials. The synthesis of low-cost composite matrices from agricultural and industrial by-products and low-cost organic and mineral sources was carried out. The feedstock materials being considered include chitosan (generated from industrial seafood waste), coir fibre (an agricultural by-product), spent coffee grounds (a by-product from coffee machines), hydroxyapatite (from bovine bone), and naturally sourced aluminosilicate minerals such as zeolite. The novel composite adsorbents were prepared using commercially sourced HAp and bovine sourced HAp, with two types of adsorbents being synthesized, including two- and three-component composites. Standard synthetic methods such as precipitation were developed to synthesize these materials, followed by characterization of their structural, physical, and chemical properties (by using FTIR, TGA, SEM, EDX and XRD). The synthesized materials were then evaluated for their ability to remove metal ions from solutions of heavy metals using single-metal ion type and two-metal ion type solution systems, using the model ion solutions, with quantification of their removal efficiency. It was followed by experimentation using the synthesized adsorbents for metal ion removal in complex systems such as an industrial input stream solution system obtained from a local timber treatment company. Two-component composites were considered as control composites to compare the removal efficiency of the three-component composites against. The heavy metal removal experiments were conducted under a range of experimental conditions (e.g., pH, sorbent dose, initial metal ion concentration, time of contact). Of the four metal ion systems considered in this study (Cd2+, Pb2+, Cu2+ and Cr as chromate ions), Pb2+ ion removal by the composites was found to be the highest in single-metal and two-metal ion type solution systems, while chromate ion removal was found to be the lowest. The bovine bone-based hydroxyapatite (bHAp) composites were more efficient at removing the metal cations than composites formed from a commercially sourced hydroxyapatite (cHAp). In industrial input stream solution systems (containing Cu, Cr and As), the Cu2+ ion removal was the highest, which aligned with the observations recorded in the single and two-metal ion type solution systems. Arsenate ion was removed to a higher extent than chromate ion using the three-component composites, while the removal of chromate ion was found to be higher than arsenate ion when using the two-component composites (i.e., the control system). The project also aimed to elucidate the removal mechanisms of these synthesized composite materials by using appropriate adsorption and kinetic models. The adsorption of metal ions exhibited a range of adsorption behaviours as both the models (Langmuir and Freundlich) were found to fit most of the data recorded in different adsorption systems studied. The pseudo-second-order model was found to be the best fitted to describe the kinetics of heavy metal ion adsorption in all the composite adsorbent systems studied, in single-metal ion type and two-metal ion type solution systems. The ion-exchange mechanism was considered as one of the dominant mechanisms for the removal of cations (in single-metal and two-metal ion type solution systems) and arsenate ions (in industrial input stream solution systems) along with other adsorption mechanisms. In contrast, electrostatic attractions were considered to be the dominant mechanism of removal for chromate ions

    Conscience and Consciousness: British Theatre and Human Rights.

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    This research project investigates a paradigm of human rights theatre. Through the lens of performance and theatre-making, this thesis explores how we came to represent, speak about, discuss, and own human rights in Britain. My framework of ‘human rights theatre’ proposes three distinctive features: firstly, such works dramatise real-world issues and highlights the role of the state in endangering its citizens; secondly, ethical ruptures are encountered within and without the drama, and finally, these performances characteristically aspire to produce an activist effect on the collective behaviours of the audience. This thesis interrogates the strategies theatre-makers use to articulate human rights concerns or to animate human rights intent. The selected case-studies for this investigation are ice&fire’s testimonial project, Actors for Human Rights; Badac Theatre; Jonathan Holmes’ work as director of Jericho House; Cardboard Citizens’ youth participation programme, ACT NOW; and Tony Cealy’s Black Men’s Consortium. Deliberately selecting companies and performance events that have received limited critical attention, my methodology constellates case-studies through original interviews, durational observation of creative working methods and proximate descriptions of practice. The thesis is interested in the experience of coming to ‘consciousness’ through human rights theatre, an awakening to the impacts of rights infringements and rights claiming. I explore consciousness as a processual, procedural, and durational happening in these performance events. I explore the ‘éffect’ of activist art and examine the ways in which makers of human rights theatre aim to amplify both affective and effective qualities in their work. My thesis also considers the articulation of activist purpose and the campaigning intent of the selected theatre-makers and explores how their activism is animated in their productions. Through the rich seam of discussion generated by the identification and exploration of the traits of a distinctive human rights theatre, I affirm the generative value of this typological enquiry
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