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Improving biocide evaluation using propidium monoazide (PMA) viability staining technique
No full textChemical biocides are commonly employed to manage problems caused by microbial processes. In the energy sector, for example, engineered systems are often treated with biocides to control microbiologically influenced corrosion (MIC), biofouling, and the biological generation of hydrogen sulfide. Standard DNA-based methods that are widely used to assess biocide effectiveness often cannot distinguish between live and dead microorganisms, potentially leading to inflated estimates of living cell populations. Incorporating propidium monoazide (PMA) viability staining technique offers a promising solution to this limitation. In this study, we explored the application of PMA within a standard DNA-based workflow to evaluate biocide performance more accurately. A model sulfate-reducing microbial consortium, derived from oilfield produced water, was exposed to widely used biocides including glutaraldehyde (Glut) and tetrakis(hydroxymethyl)phosphonium sulfate (THPS). PMA was applied prior to standard DNA extraction and subsequent qPCR and amplicon sequencing procedures. We observed PMA-derived microbial abundance at least an order of magnitude lower compared to that without PMA. The reduced PMA-derived microbial abundance correlated with the lower ability of the model microbial communities to produce hydrogen sulfide - an association that was absent based on the usual approach without PMA. Biocide-treated communities, in comparison to untreated controls, displayed significant alterations in their microbial ecological properties, such as alpha diversity, beta diversity, and taxonomic composition, as determined through 16S rRNA gene sequencing - differences that were only apparent when PMA was applied. These results confirm that incorporating PMA into standard DNA-based biocide assessment protocols is both feasible and beneficial. Since PMA implementation requires minimal additional effort, we advocate for its adoption in future biocide performance studies, in particular for engineered systems in the energy industry
Lost in the Story: The Impact of Narrative with a Direction-Giving Robot
No full textSharing a story alongside an expository response is inherently human, often enhancing communication by adding personal details based on our unique experiences to what we say. When used in a task environment, narratives may be used to exploit measurable effects, such as on memory recall or interaction engagement. With the increasing presence of social robots in everyday environments, it remains unclear whether narrative communication from robots (e.g. “This picture shows a family who recently...”) instead of a factual description yields similar benefits to those observed in human-human interactions. In this paper, we develop and study a direction-giving robot, comparing three styles of navigation instruction: narrative with landmarks, landmarks only, and baseline without landmarks. We evaluate the effects of these conditions on recall, task success, and social acceptability factors (N=38) using a Furhat robot receptionist in a lab environment.Our findings show that landmark-based navigation significantly enhances perceived usefulness, task success, and social acceptability compared to baseline. Furthermore, narrative-based navigation led to significantly higher recall of individual landmarks and improved perceptions of the robot’s adaptability. These results suggest that narratives can play a practical role in enhancing task-based HRI, particularly in scenarios that demand long-term engagement, user-centered adaptability, or memory retention (e.g. education, or explainability in AI systems).This work contributes to the broader conversation on incorporating human-like conversational features in robots and highlights narratives as a potential tool for designing more effective human-robot interactions
StorySculptor: Offering a personalised text-based gaming experience using Large Language Models (LLMs)
No full textThis study explored the integration of large language models (LLMs) into the realm of interactive fiction (text-based gaming) and aimed to bridge natural language processing techniques with the domain of storytelling. The study dives into the current state-of-the-art applications of LLMs and their capacity to generate narratives in real-time gaming environments. The paper further highlighted the implementation steps and focused on proposing a novel application of LLMs: developing a game agent designed to act as an active participant in interactive text games such that it is capable of adapting narratives based on player input and contributing to a more personalized gaming experience. By developing a novel system, the research contributes to the field through the following key advancements: (1) the creation of a novel dataset, generated using GPT-4, specifically designed to fine-tune LLMs for interactive gaming scenarios, and (2) the successful fine-tuning of the Mistral 7B instruct model, enabling dynamic game narrative generation
The performance of government-backed venture capital investments
No full textIn this research, we analyzed how different types of venture capital investments—private, public, and indirect public—affected the performance of portfolio companies. We used data of >20,000 VC deals in Europe between 2000 and 2018 from different institutional settings (public/indirect/private) that included almost 5000 investors. We found that public VC investors performed consistently worse than purely private ones, while indirect public investments (such as the “Juncker Plan” or InvestEU investments) performed consistently better. We associate these findings with the access of public funds to specific cliques of investors. In contrast, indirect funds invested in funds with comparatively better network profiles. This means that indirect public investors were capable of picking the best-performing funds but did not add any value above this. We confirmed the main conclusions using instrumental variable specifications
The deep structure of the Pernambuco Plateau, Northeast Brazil, and its implications for Equatorial Atlantic rifting
No full textThe Pernambuco Plateau Basin (PPB) of northeastern Brazil contains an important record of continental rifting at the boundary between the major South Atlantic basins and the Equatorial Atlantic Gateway (EAG). The geology and structure of the PPB is described using high quality long-offset multi-channel seismic data. The deep seismic imaging reported here shows that the PPB is not thick continental crust with a thin sediment veneer but thinned continental crust with half grabens in which sediment thicknesses reaches in excess of 3 km. Within these deep grabens we find large halokinetic structures in the form of salt diapirs and pillows that root into the early syn-rift. Sub-marine volcanic edifices are also clearly imaged, the oldest of which have bases close to the syn-to-post rift transition. We discuss the PPB evolution integrating the implications of the newly observed evidence for syn-rift salt deposition and early post-rift sub-marine volcanic activity as well as a reanalysis of recent plate models. The proposed best fit model has PPB rifting in the Aptian and early Albian, with final break-up relatively late in the Albian
Multiphase Computational Fluid Dynamics Simulation-Based Performance Investigation of Hydrogen Production With Patterned Electrodes in Alkaline-Water Electrolysis
No full textHydrogen has emerged as a clean fuel for the energy transition toward net-zero carbon emissions, with water electrolysis identified as the most promising method for green hydrogen production at scale. Increasing cell efficiencies involves improving every part of the system, including the electrodes. Recent investigations have shown that electrode surface structure affects hydrogen evolution by increasing the active surface area for reactions with micro-pillars and pits, which have complex manufacturing processes. This study investigates surface macro-pits and patterns for industrial applications. Steady-state, multiphase computational simulations were carried out to investigate the characteristics of flat/macro-dimpled electrodes for hydrogen evolution. Results show that macro-dimples significantly eliminate static gas pockets and dimple size affects the hydrogen evolution process. To predict hydrogen evolution from patterned cathode electrodes, an artificial neural network model was developed—surface area, current density, and cathode position as variables. The developed model was trained using 440 data points extracted from simulations. High predictive accuracy was obtained. The model achieved a high coefficient of determination of 0.9772 and a low root mean squared error of 0.0022, indicating an excellent fit with the data. These findings highlight the potential of a macro-patterned electrode for controlling hydrogen bubble evolution for improved green hydrogen production performance
Distribution and origin of carbon dioxide in the East Irish Sea Basin: implications for carbon storage:implications for carbon storage
No full textThe natural occurrence of carbon dioxide in subsurface reservoirs is proof of concept that it can be securely stored over geological timescales. Gas accumulations naturally enriched in CO2 were identified in the East Irish Sea Basin, and their origin was evaluated using a large well and geophysical database. Legacy petroleum fluid samples indicate that CO2 is regionally negligible, except within the proximal North Morecambe and Rhyl gas fields in the northern basin. Despite relatively elevated ionic concentrations within the northern basin, interpretations of CO2 dissolution from formation water samples are not conclusive due to widespread contamination. Geochemical measurements of Carboniferous coal and shale samples indicate that units are typically mature and are lacking any further generative potential. While the accumulated CO2 may have been generated from Carboniferous limestones or formerly organic-rich units, this is likely to have been limited based on their burial history and widespread extent compared to the local present-day distribution of CO2. Instead, thick and densely spaced Paleogene igneous dykes were mapped near the Rhyl Field. Despite being the most likely origin, igneous intrusions are interpreted across the northern basin and near several accumulations that lack CO2, suggesting that other geological elements have influenced its contemporary distribution, such as the cap rock or migration
Cyclic behavior of a replaceable LYP steel link with corrugated web: Parametrical analyses and design recommendations
No full textIn order to establish a rapid recoverable structural system in earthquake prone area, a novel replaceable low yield point steel link with corrugated web (LCSW link), consisting of the low yield point steel corrugated web with the top flange, the bottom flange, and the endplates, was proposed and tested in previous research. In this paper, a series of finite element (FE) models was established and validated to further study and understand the influence of different design parameters on the cyclic behaviors in terms of the hysteretic curves, initial stiffness, over-strength factor and cumulative energy dissipation. The analytical results indicate that the hysteretic behaviors of the specimens were obviously affected by the span-to-height ratio, the ductility and energy dissipation capacity were significantly improved by using low yield point steel (LYP steel). Furthermore, some recommendations have been introduced for the design of LCSW links in economic and safety side: the smallest ratios for flange slenderness and CSW height-to-thickness were recommended as 8.33 and 95 respectively; Flange-to-web thickness ratio was recommended to be greater than 2.0. In addition, the corrugation angle of CSW was recommended to be more than 45°, and the horizontal panel-to-wavelength ratio can be initially taken as 0.34. Finally, simple design equations for the skeleton curves were proposed and validated for LCSW links with recommended geometric dimensions
Persistence of Links in Risk-Sharing Networks: Evidence From Rural Ethiopia
No full textMost rural households in developing countries rely on agriculture for their income. They face related risks due to various shocks. In rural Ethiopia a majority of surveyed households reported to have experienced rainfall related shocks, about a third reported crop pest or diseases related shocks. Given that asset, insurance and credit markets are either missing or poorly developed, households face significant constraints in insuring themselves against these shocks. They often rely on the accumulation and depletion of assets (livestock, etc.), savings, borrowing, diversification of economic activities and on risk-sharing networks. Using a unique feature of an Ethiopian longitudinal dataset collected in 2004 and 2009, we investigate the persistence of links within households' risk-sharing networks. We do this by looking at two types of attributes: i) household characteristics such as demographics, assets, location; ii) link attributes such as relationship between households, types of arrangement (money lending, labor-sharing, etc), co-membership in local groups as well as observable differences in income and assets holdings. We investigate whether households sustain these links more on the basis of economic or financial factors such as wealth or more on the basis of social factors such as geographical proximity and shared kinship. Using logit estimation techniques, we find that many of our proxies for social factors play a significant role in the persistence of links in risk-sharing networks. Livestock and land endowments do not seem to play an important role. Local or governmental institutions aiming at bolstering persistence of informal risk-sharing arrangements could focus on networks which have a more local geographically dense structure, or one based on shared kinship. To our knowledge, this is the first time that both the 2004 and 2009 rounds of this large survey are combined. They have a rare feature: they are refined enough to allow us to identify precisely links or the individuals on whom one relies in case of needs. We can thus identify precisely which links persist (being reported both in 2004 and 2009) and which attributes significantly impact persistence. Given this particular attribute of this dataset we have yet to see in the literature a comparable analysis
Complete dynamic model of a Slinky based on torsion springs
No full textIn this paper a dynamic torsion spring model is extended to be applicable to Slinky's with a wide range of possible initial configurations. In the extended model the coil-on-coil impact is modelled by conserving momentum and modelling the impact as an inelastic impact with a zero coefficient of restitution. The extended model is applied to a plastic Slinky and a steel Slinky. The extended model is demonstrated to have the qualitatively correct dynamic behavior. The extended torsion spring model is now in a form to be applied to a wide range of Slinky behavior such as pseudo-levitation, wave propagation phenomena and stair walking
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