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Portable microfluidic devices for monitoring antibiotic resistance genes in wastewater
Get PDFAntibiotic resistance genes (ARGs) pose serious threats to environmental and public health, and monitoring ARGs in wastewater is a growing need because wastewater is an important source. Microfluidic devices can integrate basic functional units involved in sample assays on a small chip, through the precise control and manipulation of micro/nanofluids in micro/nanoscale spaces, demonstrating the great potential of ARGs detection in wastewater. Here, we (1) summarize the state of the art in microfluidics for recognizing ARGs, (2) determine the strengths and weaknesses of portable microfluidic chips, and (3) assess the potential of portable microfluidic chips to detect ARGs in wastewater. Isothermal nucleic acid amplification and CRISPR/Cas are two commonly used identification elements for the microfluidic detection of ARGs. The former has better sensitivity due to amplification, but false positives due to inappropriate primer design and contamination; the latter has better specificity. The combination of the two can achieve complementarity to a certain extent. Compared with traditional microfluidic chips, low-cost and biocompatible paper-based microfluidics is a very attractive test for ARGs, whose fluid flow in paper does not require external force, but it is weaker in terms of repeatability and high-throughput detection. Due to that only a handful of portable microfluidics detect ARGs in wastewater, fabricating high-throughput microfluidic chips, developing and optimizing recognition techniques for the highly selective and sensitive identification and quantification of a wide range of ARGs in complex wastewater matrices are needed.This work was supported by the National Natural Science Foundation of China (42377456), Guizhou Provincial Science and Technology Projects (Qiankehe Jichu-ZK [2022] Yiban 565, Qiankehe Platform Talents-GCC [2023] 046), the Hebei Provincial Science and Technology Projects (24291703Z), and the Youth Innovation Promotion Association CAS (2023415), CAS-ANSO Fellowship (CAS-ANSO-FS-2024–34).Microchimica Act
Improving adhesion in bonded ceramics through novel additively manufactured surface geometries
No full textMany high-value industries (including medical, aerospace, and defence) utilise ceramics for their favourable properties, such as high hardness, low thermal / electrical conductivity, and chemical resistance. The latter property results from chemical inertness. However, this inertness leads to weaker bond strengths when joining ceramics with other materials, as is often required to overcome their brittle nature and low tensile strength.Geometries can be introduced to the surface of a material to act as adhesion promoters through increasing the surface area of the bond, but more interestingly through mechanical interlocking between the ceramic and bonding material. Whilst this would be impossible to achieve through conventional manufacturing techniques, additive manufacturing (AM) can create these novel surface geometries. This work pushes the capabilities of ceramic AM at a scale of no greater than 500 µm, finding the limits of the current technology. Furthermore, the potential for increased bonding through the generated geometries is investigated.Engineering and Physical Sciences Research Council (EPSRC)Rheinmetall BAE Systems Land (RBSL)UKRIDefence and Security Doctoral Symposia 2024 (DSDS24
Unsteady swirl distortion in a short intake under crosswind conditions
Get PDFUnder crosswind operating conditions, the flow field of an aero-engine intake can be characterized by notable unsteady flow distortion. These distortions are typically associated with flow separation within the intake as well as with the ingestion of the ground vortex. This unsteady flow distortion can have a detrimental effect on the intake performance and potentially on the operability of the downstream compression system. Measurements of the unsteady velocity field within a model-scale intake under crosswind conditions were acquired using stereo particle image velocimetry (S-PIV). This work analyzes the S-PIV data to quantify the unsteady flow distortion, as well as the characteristics of the ingested ground vortex, in a short intake under crosswind conditions. The swirl distortion metrics were calculated for a range of crosswind velocities and intake mass flow capture ratios (MFCRs). The conditions at which the intake flow separates depend on crosswind velocity, ground clearance, the design of the intake, and the MFCR. Flow characteristics of both low MFCR diffusion-driven and high MFCR shock-induced separation were identified. The circumferential extent and intensity of the swirl distortion are strongly dependent on the crosswind velocity and mass flow rate. The swirl distortion caused by the diffusion-driven separation is greater than that due to the shock-induced separation. The diffusion-driven separation affects a larger portion of the intake aerodynamic interface plane with greater time-averaged and peak distortion levels compared to shock-induced separation. The ground vortex characterization at the aerodynamic interface plane showed a decreasing level of unsteadiness in vortex meandering with increasing MFCR.This work presented in this paper was conducted under project NIFTI which received funding from the CLEAN SKY 2 Joint Undertaking (JU) under Grant Agreement no. 864911. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and the CLEAN SKY 2 JU members other than the Union.AIAA Journa
Rebuilding airline networks in the post-COVID-19 era: new network configurations in Europe?
Get PDFAfter the standstill generated by theCOVID-19 outbreak, airlines were forced to adapt their operations and strategies to the new market requirements and constraints both in terms of supply and demand. The initial recovery included many short-term decisions for survival. Yet, as the market recovered, sometimes in new forms, airlines rebuilt their networks for a new long-term future. In this chapter, we compare the pre- and postpandemic network configurations of a selection of European airlines using a combination of network structure, topology, and connectivity indicators, which help understand airlines’ network economics. As a general trend, low-cost carriers recovered faster than full-service ones, in many cases already exceeding prepandemic supply volumes. However, our study shows the high heterogeneity of responses and postpandemic network structures across business models.While some airlines kept very similar structures, adapting to the demand change, some opted for a bolder strategy, growing their networks compared to prepandemic levels. Also, in some cases, new regulations or other external events forced the changes in networks. Finally, although in 2022 data still showed long-haul markets a little behind compared to prepandemic figures, signs such as the continued passenger increase and the ramp up of aircraft orders by airlines point toward a full recovery leading back to a sector based on continued traffic growth.Consellería de Cultura, Educación e Ordenación UniversitariaThe Spanish and Galician administrations financially supported this research through project PID2022-136983NB-I00, funded by the Agencia Estatal de Investigación, and grant ED431C 2022/37, funded by the Consellería de Cultura Educación e Ordenación Universitaria, Xunta de GaliciaAdvances in Airline Economic
Designing safety interventions for specific contexts: results from a literature review
Get PDFA misalignment between safety interventions and the workplace context of their application could lead to diminished effectiveness or failure. This paper is the first of three of an umbrella study that aimed to understand whether and how researchers and organisations consider contextual factors in safety interventions. Through Rapid Evidence Assessment (REA) process, we searched and selected scholarly work indexed in the bibliographic databases Medline, APA PsycArticles, Web of Science and Scopus between January 2011 and June 2021. The studies were analysed using a framework developed according to translation theory about (de)contextualisation of knowledge. The framework was enriched to consider psychosocial factors at the organisational level and physical, cognitive and emotional factors of the interventions’ recipients. We identified 73 eligible studies, of which 47 described safety interventions that had not been deployed in workplaces (e.g., pilot studies and concepts) and 26 studies referred to those deployed. No study considered all factors of the framework. Communication and support from management and colleagues were the most considered psychosocial factors, whereas conflicting demands and job security were the least considered. Moreover, cognitive factors of workers were mentioned in 77% of the sample, with only one study considering inclusively cognitive, emotional and physical factors of recipients. About 62% of the implemented interventions were functional (e.g., training, education and communication-related interventions), with only four studies reporting physical interventions. Also, most of the interventions were sourced from the literature and introduced as ‘new practice’ at the targeted workplaces, with only one article reporting a failed intervention. Overall, the findings of this research indicated that intervention studies did not visibly follow a translation-transformation path between sources and recipients, did not systematically consider contextual factors at the workplaces targeted, and all interventions represented administrative controls, contrary to the widely accepted principle of the hierarchy of controls
As ATMIS looks to withdraw, the risk of large-scale al-Shabaab success in southern Somalia is high
Get PDFIn March this year, the African Union (AU) expeditionary force in southern Somalia—which started off as AMISOM but is now the African Union Transition Mission in Somalia (ATMIS)—reached its 17th year. The mission will end on December 31, 2024, and it will be replaced by a new African Union Stabilization and Support Mission in Somalia (AUSSOM). United Nations Security Council approval will have to be given this month to meet the changeover deadline. Yet the new force is unlikely to significantly degrade the long-term threat al-Shabaab poses. al-Shabaab is stronger than generally perceived and may be in a position to achieve significant large-scale success.Global Observator
Focus Group file for Managing Cyber security Risks across Consumers, Organisations and Sectors
No full textFocus Group transcriptionsThis project was funded by the Engineering and Physical Sciences Research Council (EPSRC), as part of UK Research and Innovation, for a two-year project titled Managing Cybersecurity Risks across Consumers, Organisations, and Sectors (MACRO). The project focused on addressing cybersecurity challenges within the context of Mobility-as-a-Service (MaaS).
MaaS offers travelers a unified service that integrates various forms of transport through a single point of delivery. It has the potential to reduce traffic congestion, improve customer convenience, and address social inequalities while lowering carbon emissions through increased public transport use. Ensuring the success of MaaS requires a single application for journey planning and execution, a software system capable of integrating multiple providers, and AI-based analytics to optimize journeys and resource utilization. However, these features make MaaS systems vulnerable to a wide range of cyberattacks, which can impact various stakeholders. The complexity of the MaaS ecosystem, which includes customers, transportation providers, and data providers, and its reliance on data, creates unique cybersecurity challenges.The MACRO project explored the impact of cybersecurity risks on public perceptions and acceptance of MaaS. It examined how previous encounters with data breaches influenced attitudes toward MaaS adoption and evaluated public opinions of MaaS in the context of different cybersecurity risk or data breach scenarios.Engineering and Physical Sciences Research Council (EPSRC
Innovative clearance data model for demining operational data collection: insights from field trials in Zimbabwe
Get PDFFrom September 2023 to March 2024 a field trial on a live manual demining site was conducted to test a new and innovative approach for the collection and analysis of operational data. The approach, titled the Clearance Data Model, involved the collection of sixty-six data attributes for each mine found. For the first time the mine itself would become the accountable unit of demining data, against which an expanded range of relevant attributes particular to that specific mine would be recorded. This novel approach represented a considerable expansion to the operational data collected concerning Victim Operated Explosive Devices such as mines, booby-traps and victim operated Improvised Explosive Devices from the field. Previously few if any details about individual accountable mines were collected. The trial proved that is it entirely practical to collect such levels of data without impeding operational efficiency. It also showed that such data has significant benefits for quantitative operational risk management, as well as overall operations and quality management. For example, the recording of mine depth alongside excavation times enables oversight of individual excavation speed and management of any risk identified.Heliyo
Introducing the combustion continuum to define the transition points between burning, deflagration, and detonation regimes of energetic materials
Get PDFThis paper introduces what the authors term Combustion Continuum which treats oxidation reactions of energetic materials as lying on a continuum in which the variable is the speed of reaction. It divides the continuum into three regions, burning, deflagration, and detonation (BDD) and defines the transition points between each region and describes various observable effects that allow definitive identification of the type of reaction. The transition point between combustion and deflagration is defined as the onset of an atmospheric shock wave, which is the first time deflagration has been defined in such a way that the point of transition can be observed and fixed. The transition point between deflagration and detonation is well defined elsewhere and is the point at which the reaction shocks-up to produce a shock wave driven detonation front. This approach contrasts with most literature that treats burning, deflagration and detonation as interrelated forms of energetic reaction with none giving precise definitions that allow a full understanding of the difference between them and most critically, how to determine whether a reaction is burning or deflagration.This work was sponsored by Alford Technologies Ltd who provided logistics and technical resources for the research but played no role in the study design, collection, analysis and interpretation of data, the writing of the report and the decision to submit the paper for publication.Journal of Energetic Material
Temperature effects on seed germination and seedling biochemical profile of cannabis landraces
Get PDFThis study investigated the effect of temperature on the germination and seedling biochemical profiles of eight cannabis landraces, namely Ladysmith Ugwayi wesiZulu (L1) and Iswazi (L2), Durban Poison (H1), Bergville Ugwayi wesiZulu (B1), Natal (B2), and Iswazi (B3), and Msinga Ugwayi wesiZulu (M1) and Iswazi (M2). Seed viability, germination rate, and germination percentage were evaluated along with seedling amino acids, carbohydrates, and fatty acids methyl esters (FAMEs) under day/night temperature regimes of 20/15 °C, 30/25 °C, and 40/35 °C. Results showed a significant effect (p < 0.001) of temperature on germination percentage, rate, and biochemical profiles of cannabis landraces. Landraces L1, B1, H1, B2, and M1 had higher germination at 20/15 °C, while B3, M2, and L2 performed better at 30/25 °C. Biochemical profiles varied with temperature and landraces. Amino acid content increased with temperature but did not correlate with germination indexes. Carbohydrates and FAMEs decreased with rising temperature, peaking at 30/25 °C. FAMEs strongly correlated with germination indexes, linking lipid composition to seed performance. Sorbitol positively correlated with germination, while glucose and fructose showed indirect correlations. This study underscores the impact of temperature on germination and the biochemical profiles of cannabis landraces, highlighting the importance of considering genotype-specific responses in varietal selection.This research was funded by the Moses Kotane Institute, grant number 211526424.International Journal of Plant Biolog