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Influence of graphene nanoplate size and heat flux on nanofluid heat exchanger performance: A molecular dynamics approach
No full textThis study aimed to enhance the thermal efficiency of nanofluid-based heat exchangers by exploring the simultaneous effects of external heat flux and graphene nanoplate sizes on thermal and structural characteristics. Effective heat transfer is a critical requirement for managing heat in microscale systems, where optimizing the thermal performance of nanofluids can improve device performance. Molecular dynamics simulations were carried out of a sinusoidal inner surface copper heat exchanger coated with silicon nanoparticles to demonstrate atomic-level interaction within the nanofluid. The significant findings showed that while an external rising heat flux decreased heat flux from 41.7 to 37.26 W/m² and thermal conductivity of nanofluid from 14.53 to 13.80 W/m·K, only an increase in viscosity from 0.32 to 0.49 mPa·s, the agglomeration time of nanoparticles decreased from 3.71 to 3.33 ns and friction coefficient from 0.022 to 0.015, could indicate a difference in particle behavior responding to the thermal stress. However, the size of the graphene nanoplate from 5 to 15 Å increased the heat flux from 40.05 to 46.77 W/m² and thermal conductivity of the nanofluid from 14.15 to 14.99 W/m·K, since the larger graphene nanoplate films can produce a more substantial covalent bonding and link interlayer coupling. In contrast, the larger nanoplate also enhanced viscosity from 0.30 to 0.39 mPa·s, aggregation time from 3.64 to 4.01 ns, and friction coefficient from 0.020 to 0.026, which indicated lower particle mobility. This study was the first of its kind to contribute to the existing knowledge gap by investigating the simultaneous effect of both the nanoplate size and external heat flux in an oscillating microchannel heat exchanger. The knowledge provided offers an experimental pathway in optimizing the nanofluid properties and the heat exchanger geometry for improved thermal management for compact and microscale applications
Teachers’ perceptions towards research engagement and its relation to their continuous professional development: case of Algerian University teachers of English
No full textThis research investigates the perceptions of 12 Algerian university teachers towards research engagement and the perceived relation between their research engagement and their Continuous Professional Development (CPD). The significance of language teachers' CPD is evident in institutional demands for professional development and the growing interest among academics, teacher trainers, and managers in improving CPD models. Previous studies have highlighted the potential impact of teachers' research engagement on their CPD. However, not much research is conducted in the Algerian context regarding language teachers research engagement. Thus, more research is needed to give voice to teachers as active agents in expressing their thoughts on research engagement and its relationship to CPD.
This study emphasizes the importance of understanding the factors affecting language teachers’ research engagement and how teachers’ research engagement contribute to their CPD. It aims to answer the following questions: (i) what are the perceived environmental factors affecting research engagement among the participating teachers? (ii) What are the personal factors that seem to affect research engagement among the participants? (iii) how do the participants perceive the relation between research engagement and their CPD? To address these research questions, I employed a qualitative case study where I relied on online semi-structured interviews with 12 Algerian University teachers of English during the Covid-19 Pandemic. In order to analyse the data, I relied on Braun and Clarke’s (2022) reflexive thematic analysis. To interpret my findings, I used Bronfenbrenner’s (1979) Ecological System Theory in addition to the Self-determination theory developed by Edward L. Deci and Richard M. Ryan (1980).
The findings reveal that participants emphasize various environmental factors operating at different levels, which negatively affect their research engagement to varying degrees. Therefore, understanding not only the environmental factors but also the interconnections between these factors and the weight each environmental factor carries is crucial before further research engagement can be encouraged. Regarding personal factors, the findings highlight how variations in individual teachers’ motivational orientations can differently affect their research engagement. Teachers who perceive themselves as researchers, lifelong learners, and agents of change tend to orient towards more intrinsic types of motivation, integrating values that align with the importance of research engagement. This intrinsic orientation can lead to sustained research engagement and mitigate some of the environmental barriers. Furthermore, the data emphasizes the need for a more dynamic characterization of teachers’ research engagement, considering the challenging environmental factors and accounting for its impacts on teachers, students, institutions, and the wider community. Strict adherence to rigid academic standards may misrepresent the efforts made by university teachers in specific contexts.
The originality of this study lies in its novel approach to exploring a group of language teachers' research engagement by integrating two psychological theories inspired by the data. It focuses on perceived environmental and personal factors influencing language teachers' research engagement while also amplifying the voices of university teachers on the teaching-research nexus. This thesis provides a detailed examination and hierarchization of the environmental factors influencing language teachers' research engagement and how teachers' motivational orientations can help mitigating some of these factors to facilitate research engagement.
The study concludes that institutions striving to increase research engagement among language teachers should dedicate serious efforts to improving the environment surrounding teachers. Teachers, in turn, need to reflect on the sources of their motivation and integrate values that align with research. Additionally, they need to cultivate a proactive mindset, which is crucial, particularly in cases where the environment is not conducive to research engagement. This study also underscores the need to reconsider the teachers’ research engagement concept within the Continuing Professional Development (CPD) framework. Thus, it proposes a continuum to characterize language teachers’ research engagement at the university level. Finally, the current study suggests a two-dimensions model that can help predict the potential impact of the intersection between the varying environmental conditions and the different motivational orientations among the individual language teachers on research engagement. Thus providing a heuristic device for teachers, researchers, and the wider academic community to reflect upon the existing conditions within their contexts and make informed decisions on potential effective interventions to maximize a meaningful contribution of teachers’ research engagement to their CPD
The role of sport involvement on residents’ evaluation of Youth Olympic Games benefits, quality of life, and event support
No full textThe study aimed to examine how host city residents’ sport involvement influences certain psychological concepts such as involvement with mega-events, evaluation of event benefits, community quality of life (CQoL), and ultimately event support. Data were collected from an online resident panel from the two host cities of the 2016 Youth Olympic Games (YOG) using a web survey with 294 subjects. Structural equation modeling was used to test the study's six hypotheses. The results supported the proposed model indicating the influential role of sport involvement on the psychological involvement with the YOG, which subsequently positively influenced the evaluation of YOG benefits, which in turn increased residents’ CQoL and event support. YOG involvement fully mediated the relationship between general sport involvement and YOG benefits. The findings contribute to involvement and social exchange theories by shedding light on the variables that enhance mega-event resident support and quality of life
Dry Reforming of Methane Using Gd-promoted Ni/SBA-16 Catalyst: Structure, Activity and Process Optimization with Response Surface Methodology
No full textThis work examines the effect of gadolinium (Gd) promotion on nickel-based SBA-16 catalysts for the dry reforming of methane (DRM), with the goal of improving syngas production by optimizing catalyst composition and operating conditions. Catalysts with varying Gd loadings (0.5–3 wt.%) were synthesised using co-impregnation. XRD, N2 physisorption, FTIR, XPS, and H2-TPR–CO2-TPD–H2-TPR were used to examine the structural features, textural properties, surface composition, and redox behaviour of the catalysts. XPS indicated formation of enhanced metal–support interactions, while initial and post-treatment H2–TPR analyses showed that moderate Gd loadings (1–2 wt.%) maintained a balanced distribution of reducible Ni species. The catalysts were tested for DRM performance at 800 °C and a gas hourly space velocity (GHSV) of 42,000 mL g−1 h−1. 1–2 wt.% Gd-promoted catalysts achieved the highest H2 (~67%) and CO yield (~76%). Response surface methodology (RSM) was used to identify optimal reaction conditions for maximum H2 yield. RSM predicted 848.9 °C temperature, 31,283 mL g−1 h−1 GHSV, and a CH4/CO2 ratio of 0.61 as optimal, predicting a H2 yield of 96.64%, which closely matched the experimental value of H2 yield (96.66%). The 5Ni–2Gd/SBA-16 catalyst exhibited minimal coke deposition, primarily of a graphitic character, as evidenced by TGA–DSC and Raman analyses. These results demonstrate the synergy between catalyst design and process optimization in maximizing DRM efficiency
Emicizumab utilization, safety, and outcomes in people with severe hemophilia and no inhibitors: 3-year follow-up. A report from the UK Haemophilia Centre Doctors' Organisation.
No full textBackground
Emicizumab prophylaxis is restricted to severe hemophilia A in the UK. Treatment choice and safety remain a matter of debate.
Objectives
This study was conducted to investigate factors influencing treatment choice, continued use, safety, and clinical outcomes associated with emicizumab in a national cohort of persons with severe hemophilia A without current inhibitors.
Methods
A 3-year study was conducted in 618 persons with severe hemophilia A who switched to emicizumab and 413 who continued factor (F)VIII prophylaxis. Outcome measures included annualized bleed rates (ABRs), the Hemophilia Joint Health Score, and health-related quality of life.
Results
Switchers and nonswitchers had a similar median age (26 and 28 years, respectively). Switchers had a significantly higher median (IQR) ABR than those continuing FVIII prophylaxis, but a significantly lower proportion had an inhibitor history (13.6% vs 20.5%; P = .0005). Thirty-one adverse events were reported, including 1 thrombosis (0.2%), 8/84 recurrent inhibitors (9.5%), 1 neutralizing antidrug antibody (0.2%), and 14/618 (2.3%) patients discontinued emicizumab. A higher prestudy median (IQR) ABR was observed in switchers compared with nonswitchers (2.05 [0.43, 6.06] vs 0.68 [0, 2.7]), reducing to a median (IQR) of 0 (0, 0) with emicizumab prophylaxis. The proportion with a zero-treated bleed rate increased from 35% to 71% (P = .001). An 82% reduction in bleeding into target joints was observed in favor of emicizumab. A modest (Δ= −2; P = .02) improvement in the total Hemophilia Joint Health Score was observed.
Conclusions
Emicizumab selection was influenced by ABR and inhibitor history but not age. Emicizumab was generally well tolerated, with only 2.3% discontinuing the drug. A significant within-person improvement in all bleeding outcomes was observed with emicizumab
A three-dimensional level set method for two-phase electrohydrodynamics with finite electric Reynolds number
No full textThe electrohydrodynamics (EHD) of droplets under electric fields underpins technologies from ink-jet printing and electrosprays to droplet sorting and microfluidics, yet accurate prediction remains challenging because most existing studies are confined to two-dimensional or axisymmetric models and often neglect surface-charge convection, a mechanism that strongly modifies interfacial stresses and breakup. To address this gap, we develop a fully three-dimensional (3D) level-set computational framework for leaky-dielectric two-phase flows that resolves bulk charge conservation, interfacial surface charge, convection, and topology change over a wide range of electric Reynolds numbers ReE (the ratio of charge-relaxation to convection time) and electric capillary numbers CaE (the ratio of electric stress to surface tension). Unlike existing three-dimensional studies that either neglect surface-charge convection or are restricted to small deformations without breakup, our framework provides a comprehensive 3D treatment of finite-ReE charge convection, topology change, and breakup mapping. The method is carefully verified (mass conservation error < 0.5%) and validated against Taylor’s small-deformation theory and silicone–castor oil experiments, confirming quantitative accuracy.Our simulations demonstrate that surface-charge convection redistributes interfacial charges, weakens EHD circulation, suppresses oblate deformation, and enhances prolate deformation; three-dimensional charge maps and two-dimensional cross-sectional contours quantify these effects in detail. For prolate drops, we capture and classify breakup transitions in full 3D—from end pinching to conic cusping and ultimately tip streaming—and construct a comprehensive (CaE, ReE) phase diagram. By integrating finite-ReE effects, 3D surface-charge diagnostics, and breakup mapping in a validated computational method, this study establishes a novel predictive framework for electric-field-driven droplet technologies
Exploring the use of non-pharmacological interventions in dementia
No full textSection A
Dementia prevalence rates are rising and caring for people as the disease progresses can be challenging. The needs of people with dementia (PWD) are multifaceted, it is imperative to meet these needs to ensure high quality care provision and subsequently, quality of life. Touch is a fundamental need of people with dementia and yet older adults can be the most deprived of touch. This review explores the literature on carers (familial and professional) of people with dementia and their experiences of using touch in their caring role. A thematic synthesis revealed carers experiences of touch included: ‘Person-centred touch’, ‘Bringing the person into focus', 'A sense of touch’, ‘Restoration & reconnection’, ‘Part of my repertoire’ and ‘the practicalities of touch’. The results are discussed considering existing literature on touch and PWD, and recommendations for practice are included.
Section B
Behaviours that challenge (BtC) are common in people with dementia and national guidelines recommend using non-pharmacological interventions (NPIs) as a first-line treatment for BtC. One training package that provides a framework for staff delivering NPIs is ‘Communication and Interaction Training’ (CAIT). The following study aimed to explore staff’s perceptions on the impact of CAIT on their management of people with dementias’ behaviours and emotions. The study also sought to further understand how CAIT works and the conditions which help implement CAIT. Reflexive thematic analysis was used to analyse interview data from staff who had recently received CAIT and plan and/or deliver NPIs for people with dementia. This resulted in six main themes: ‘Delivering dementia literacy’, ‘Transforming interactions’, ‘Accessible and flexible’, ‘Obstacles in training’, ‘Perceiving my role differently’ and ‘Ensuring the right environment’. Implications of the research on the CAIT programme are discussed as well as suggestions for future research
PaintSmartly 1: Scouting identification of one sustainable solution for cleaning painting tools contaminated with water-based paints
No full textCleaning water contaminated with water-based paints is important to protect ecosystems, prevent toxic buildup and safeguard drinking water sources. Paints contain chemicals that affect aquatic life and pollute waterways. Sustainable approaches to treatment, reduction, recycling and reuse could lessen environmental impact, support biodiversity and maintain safer water. PaintSmartly 1 is a six-week Impact Accelerator project aimed at conceptualising a sustainable method for cleaning paint equipment dirty with water-based paints (WBP). PaintSmartly 1 includes laboratory- and desk-based work and should identify at least one promising sustainable solution for cleaning WBP. PaintSmartly 1 adopts an innovative, holistic approach to conceptualising a sustainable transferable solution for cleaning WBP. PaintSmartly 1 considers key aspects such as environmental, economic, energy efficiency, health and safety. This includes reducing unpleasant odours and bacterial risks in water from cleaning WBP
Information flows, stock market volatility, and the systemic risk in global finance
No full textInformation flows are a theoretical explanation for stock market volatility, but controversy remains regarding how to measure them. Based on cross-sectional and temporal properties of information flows, we decompose total trading volume into four types: cross-country shocks and country-specific shocks due to arrivals of private information, and trading volume shocks and stock volatility shocks due to public information. We then use a Structural Vector Autoregressive model to reconstruct historical trading volume resulted from the four types of information shocks. The evidence shows that the historical trading volumes due to private information flow can explain volatility clustering of stock markets. By analysing sources of information flow, we find private information flow reflects systemic risk in the global financial system. The result conforms to Mixture of Distribution Hypothesis and finds that quality of information content is what differentiates privately informed trading from public information trading. It further suggests the main drivers of stock market volatility are uncertainties about fundamental values of assets and about other investors’ behaviours
Intra-action between academics and their areas of expertise in the quest for social equality in academia and society: a posthuman perspective
No full textThis article uses a posthuman perspective to analyse the intertwined relationship between some academics as social beings and their areas of expertise. It focuses on the intra-action between the academics and their areas of expertise to express their self-perception, resist essentialist discourses of who they are experienced as within the university setting and advocate for social justice both at the university and in wider society. Using empirical evidence from this study, linguistic, racial and religious discrimination in academia based on perceptions of accent, ‘race’ and religion are uncovered. The study also reveals intra-action between the academics and their areas of expertise to make themselves, including their social and organisational environment, happen by moving beyond stereotypical understanding of the world. The study argues for the need to acknowledge the pertinence of social issues such as ‘race’ in British higher education, rather than viewing them as irrelevant to academia. The study contributes to the existing literature on inequality and higher education by reimagining a just higher education and society using a posthumanist lens. It also has implications for policy in terms of the contribution of a single-language policy and the predominance of ‘Whiteness’ in higher education in creating and perpetuating perceptions of diversity as a problem rather than a resource for growth and bridging gaps between communities