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Stance-taking and language choice in #StopEnslavingSaudiWomen: Critical discourse analysis of campaigning discourse on Twitter
No full textTwitter, with its affordances, offers a rich site to investigate linguistic practices and the sociocultural meanings they carry in the noisy, multilingual and multi-voiced context of social media. The current study aimed to explore how Twitter users use discursive strategies and language choice to express their stances towards the guardianship system in Twitter campaigning hashtag #StopEnslaveSaudiWomen. The study deployed quantitative and qualitative methods in collecting and analysing the tweets while relying on different theories such as stance, language choice, and CMDA models that are integrated within the wider framework of critical discourse analysis. With the support of MAXQDA, 3,162 tweets were analysed following Fairclough’s three dimensional-model.Twitter users employed various discursive strategies in constructing their stances towards the guardianship system relying on different modes supported by Twitter such as pictures, emojis, videos as well as multilingual texts. The constructed stances were varied in being conservative, liberal, moderate, radical, and traditional representing a range of views on political, religious, social topics. The tweets revealed key themes/ topics that were employed differently by particular groups in English and/ or in Arabic (e.g., the driving ban) to align/ disalign with different groups; and to legitimise, delegitimise their stances and stances of other. Audience was also found to be a significant factor in language choice when taking a stance. The study has contributed to a better understanding of discursive strategies and language choice and how they are reconfigured and interrelated in the online context
Depicting the deep: the art of illustrating science
No full textSoon after its inception in 2013, the Deep‐Ocean Stewardship Initiative (DOSI) commissioned a bespoke artwork to illustrate its subject and scope. The resulting image ﴾above﴿ by artist Tanya Young has become DOSI’s calling card, used in all DOSI’s digital outlets, presentations, promotional materials and event backdrops. Its power to entice is not only in its intricate and wholesome beauty, but also in its detail and scientific accuracy of the fauna, activities and impacts it depicts. This poster explores the origin story of the artwork, the inspiration, techniques and processes that led the artist to its creation, as well as Tanya’s own story of her interest in the deep ocean as a subject matter for her art. DOSI has certainly benefited from the attention the artwork attracts, opening DOSI’s work on the provision of science‐based knowledge to a wider audience of scientists and artists alike, and showing how the art‐science collaboration is a potent tool to create understanding
Modelling the mitigation of anti-vaccine opinion propagation to suppress epidemic spread: a computational approach
No full textInformation regarding vaccines from sources such as health services, media, and social networks can significantly shape vaccination decisions. In particular, the dissemination of negative information can contribute to vaccine hesitancy, thereby exacerbating infectious disease outbreaks. This study investigates strategies to mitigate anti-vaccine social contagion through effective counter-campaigns that disseminate positive vaccine information and encourage vaccine uptake, aiming to reduce the size of epidemics. In a coupled agent-based model that consists of opinion and disease diffusion processes, we explore and compare different heuristics to design positive campaigns based on the network structure and local presence of negative vaccine attitudes. We examine twocampaigning regimes: a static regime with a fixed set of targets, and a dynamic regime in which targets can be updated over time. We demonstrate that strategic targeting and engagement with the dynamics of anti-vaccine influence diffusion in the network can effectively mitigate the spread of anti-vaccine sentiment, thereby reducing the epidemic size. However, the effectiveness of the campaigns differs across different targeting strategies and is impacted by a range of factors. We find that the primary advantage of static campaigns lies in their capacity to act as an obstacle, preventing the clustering of emerging anti-vaccine communities, thereby resulting in smaller and unconnected anti-vaccine groups. On the other hand, dynamic campaigns reach a broader segment of the population and adapt to the evolution of anti-vaccine diffusion, not only protecting susceptible agents from negative influence but also fostering positive propagation within negative regions
High-speed ultra-energy-efficient memristor-based massive MIMO SIC detector circuit with hybrid analog-digital computing architecture
No full textThe emerging memristor crossbar array based computing circuits exhibit computing speeds and energy efficiency far surpassing those of traditional digital processors. This type of circuits can complete high-dimensional matrix operations in an extremely short time through analog computing, making it naturally applicable to linear detection and maximum likelihood detection in massive multiple-input multiple-output (MIMO) systems. However, the challenge of employing memristor crossbar arrays to efficiently implement other nonlinear detection algorithms, such as the successive interference cancellation (SIC) algorithm, remains unresolved. In this paper we propose a memristor-based circuit design for massive MIMO SIC detector. The proposed circuit comprises several judiciously designed analog matrix computing modules and hybrid analog-digital slicers, which enables the proposed circuit to perform the SIC algorithm with a hybrid analog-digital computing architecture. We show that the computing speed and the computational energyefficiency of the proposed detector circuit are 43 times faster and 110 times higher, respectively, than those of a traditional 8- core digital signal processor (DSP), and also advantageous over the benchmark high-performance field programmable gate array (FPGA) and graphics processing unit (GPU)
Reference points for assessing significant adverse impacts on deep sea vulnerable marine ecosystems
No full textBiodiversity loss due to human activities is a critical issue, particularly in the High Seas where bottom-contact fishing poses a significant threat to Vulnerable Marine Ecosystems (VMEs). Deep sea VMEs, tend to be composed of slow-growing, long-lived benthic organisms such as deep-sea corals and sponges. The United Nations Food and Agriculture Organization (FAO) has developed guidelines to protect these ecosystems from Significant Adverse Impacts (SAI) caused by bottom trawling activities.This study focuses on the Northwest Atlantic Fisheries Organization (NAFO) Regulatory Area, utilizing fishery-independent surveys and fishing Vessel Monitoring System (VMS) data to map fishing intensity and VME functional type biomass. Seven VME types have been assessed, e.g., large-sized sponges, sea pens, sea-squirts, bryozoans, black corals, large and small gorgonian corals, to determine the risk of impact. Results indicate that sponges, black corals, and large gorgonians are the most sensitive VME types to bottom trawling activities, with significant biomass loss occurring at very low fishing intensities. The study defines bottom trawling biomass impact thresholds for each VME type in the range of 0.12–9.43 km·km−2·yr−1 and 0.01–0.11 km·km−2·yr−1 for upper and lower impact thresholds, respectively. The study determines that rapid losses in VME biomass occurs at bottom trawling intensities of about 0.10 km·km−2·y-1 for fisheries operating in the NAFO Regulatory Area. The study concludes that modest reductions in fishing effort in sensitive areas could substantially mitigate SAI whilst having little or no impact on fishing opportunities. The findings also support the target of protecting at least 60 % to 70 % of VME biomass to likely ensure good seabed status; and the importance of implementing spatial fisheries management measures, such as defining a fishing footprint and establishing fishery closed areas, to protect VMEs
Management of environmental impacts of fossil fuel use in refugee camps through transition to renewable energy infrastructure: case studies in Uganda and Bangladesh
No full textMany refugee camps exist for decades but associated infrastructure needs are only planned for the very short term, including provision of power. This study advocates a shift in approach to sustainable electrification of essential services in refugee camps for lighting, refrigeration, health, water, education, alongside camp operations. Qualitative and quantitative surveys were conducted in refugee camps in Uganda and Bangladesh which assessed the electrical supply needs across such categories. A range of solar photovoltaic (PV) power systems (Solar Home Systems, AC/DC mini grids) and their emission mitigation potential were modelled based on survey data. Proposed designs were compared with presently-used diesel systems in terms of applicability, environmental impact and economics. Results indicate significant cost savings are achievable through the PV systems deployment for different areas in two major refugee camps. Estimated savings range from USD31,000–140,000 and USD166,000–653,000 for five-year and twenty-year project lifetimes respectively. These savings apply to sub-areas of much larger camps, with potential savings increasing substantially if scaled to the whole camp. Results indicate that PV-battery systems were more cost-effective than diesel, even for five-year projects, with investments recoverable in second year of operation. Furthermore, replacing the existing 50 kW diesel generator in Bidi-bidi camp with a 40kWp PV-battery system would result in a reduction of 2.4 MtCO2e over a 20-year project lifetime. Adopting presented approaches will enhance humanitarian service provisions, reducing both cost and emissions. These findings are applicable to many refugee camps in Africa and Asia that have similar solar resource and lack of grid access.</p
Numerical study of transient response in amperometric and potentiometric glucose biosensors
No full textBiosensors are indispensable tools for continuous monitoring of key analytes, such as glucose, in chronic disease management. This thesis focuses on enzyme-immobilized redox polymer biosensors, leveraging reaction-diffusion partial differential equations (PDEs) to bridge the gap between theory and practical applications for biosensor design.A transient numerical scheme in MATLAB was used to solve coupled non-linear PDEs, capturing the dynamic behavior of enzyme-membrane systems. Verification was achieved by comparing steady-state analytical solutions with numerical outputs, while Case diagrams were used to identify different kinetic and transport regimes. Experiments with deflavinated enzymes provided a means to validate our model by systematically manipulating key parameters. Simulation results were compared with experimental data, revealing key insights into transient enzyme-membrane interactions.The study also investigated tubular flow electrodes, revealing the dependence of steady-state amperometric responses on solution viscosity under flow conditions. Experimentally obtained chronoamperograms were fitted to numerically solved dynamic simulations, confirming the model's predictive capabilities. Novel boundary conditions were also proposed to simulate potentiometric biosensors, broadening the scope of this work beyond amperometric sensing.Animations visualizing concentration profiles and system responses offer a deeper understanding of transient and steady-state behaviors. These insights can contribute to the optimization of biosensor performance, including sensitivity, dynamic range, and response time, advancing the development of robust and accurate glucose monitoring technologies
Ultrafast all-optical matrix-vector multiplication based on four-wave mixing
No full textWe propose a nonlinear optical approach for ultra-fast, matrix-vector multiplications as required in machine-learning tasks. Optical multiplication is experimentally demonstrated, with less than 0.05% classification accuracy reduction compared to digital results on the MNIST dataset
Review article: a comprehensive review of compound flooding literature with a focus on coastal and estuarine regions
No full textCompound flooding, where the combination or successive occurrence of two or more flood drivers leads to a greater impact, can exacerbate the adverse consequences of flooding, particularly in coastal--estuarine regions. This paper reviews the practices and trends in coastal-estuarine compound flood research and synthesizes regional to global findings. A systematic review is employed to construct a literature database of 279 studies relevant to compound flooding in a coastal-estuarine context. This review explores the types of compound flood events and their mechanistic processes, and it synthesizes terminology throughout the literature. Considered in the review are six flood drivers (fluvial, pluvial, coastal, groundwater, damming/dam failure, and tsunami) and five precursor events and environmental conditions (soil moisture, snow, temp/heat, fire, and drought). Furthermore, this review summarizes research methodology and study application trends, as well as considers the influences of climate change and urban environments. Finally,this review highlights knowledge gaps in compound flood research and discusses the implications on future practices. Our five recommendations for compound flood research are (1) adopt consistent terminology and approaches, (2) expand the geographic coverage of research, (3) pursue more inter-comparison projects, (4) develop modelling frameworks that better couple dynamic Earth systems, and (5) design urban and coastal infrastructure with compounding in mind.<br/
Assessment of near-surface undrained shear strength of soft seabeds with free fall cone penetrometer testing in the northern Baltic Sea
No full textFree fall cone penetrometer testing (FFCPT) allows for efficient site reconnaissance and soft seabed undrained shear strength (su) assessment in a shallow water environment. The FFCPT is a particularly useful tool for near-surface characterization for cable route assessment associated with offshore renewable developments. This study presents results from an in-situ FFCPT, seismoacoustic survey and sediment coring campaign in a nearshore site in the Gulf of Finland, northern Baltic Sea. An extended FFCPT interpretation model has been applied, including friction on the shaft (as well as tip resistance), rate dependency and soil buoyancy. The derived FFCPT profiles are repeatable at a given location, while the shapes of the su profiles capture different depositional environments. The derived dynamic FFCPT su is lower than measured in the laboratory by fall cone and triaxial tests. This is potentially due to hydrodynamic drag reducing the FFCPT terminal velocity and soil drag affecting the penetration depth and dynamic su; and due to the reconstituted nature of the laboratory samples and very low stress levels being considered that are difficult to achieve in the laboratory. The magnitude of derived su and characteristic shapes in the FFCPT profiles enable ground-truthing the interpretation of seismoacoustic profiles. This study contributes to the evidence base supporting the FFCPT as a valuable supplement, or to partially replace sediment coring and laboratory measurements, for offshore site assessment.</p
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