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Effect of precursor purge time on plasma-enhanced atomic layer deposition-prepared ferroelectric Hf<sub>0.5</sub>Zr<sub>0.5</sub>O<sub>2</sub> phase and performance
No full textHafnium oxide-based thin films, in particular hafnium zirconium oxide (HZO), have potential for applications in nonvolatile memory and energy harvesting. Atomic layer deposition (ALD) is the most widely used method for HZO deposition due to its precise thickness control and ability to provide conformal coverage. Previous studies have shown the effects of different metal precursors, oxidizer precursors, and process temperatures on the ferroelectric properties of HZO. However, no mechanism has been identified to describe the different phase stabilities as the metal precursor purge time varies. This study investigates how varying the metal precursor purge time during plasma-enhanced ALD (PE-ALD) influences the phases and properties of the HZO thin films. Grazing incidence X-ray diffraction, Fourier transform infrared spectroscopy, and scanning transmission electron microscopy are used to study the changes in phase of HZO with variation of the metal precursor purge time during the PE-ALD process. The phases observed are correlated with polarization and relative permittivity responses under an electric field, including wake-up and endurance effects. The resulting phases and properties are linked to changes in composition, as measured using time-of-flight secondary ion mass spectrometry and X-ray photoelectron spectroscopy. It is shown that short metal precursor purge times result in increased carbon and nitrogen impurities and stabilization of the antipolar Pbca phase. Long purge times lead to films comprising predominantly the ferroelectric Pca21 phase.<br/
Catalytic production of aviation jet biofuels from biomass: a review
No full textThe aviation sector is a major emitter of fossil fuel-derived carbon dioxide contributing to global warming. For instance, jet fuel consumed by the aviation industry is 1.5–1.7 billion barrels per year, resulting in 705 million metric tons of carbon dioxide emissions. Aircraft manufacturers have set ambitious goals, aiming for carbon-free growth post-2020 and a 50% reduction in greenhouse gas emissions by 2030. This issue can be solved by replacing fossil fuels with biofuels produced from modern biomass, thus meeting the carbon neutral objective. Here, we review the technologies to convert biomass into jet biofuel with focus on reactants, catalysts, and the chemistry of combustion. Reactants include alcohols, oil, esters, fatty acids, gas and sugars. Catalysts include Fischer–Tropsch catalysts, palladium, platinum, ruthenium, nickel, and molybdenum. The utilization of jet biofuels could potentially reduce greenhouse gas emissions by up to 80%. We also discuss economic implications.<br/
Gendered effect of well-being on likelihood of violence in Northern Irish adolescents
No full textRecent research demonstrates a rise in female-related violence. Associations between mental health and violence are well established, but the gender-specific impact remains under-evaluated. We explored how gender and well-being interact to affect likelihood of violence in a Northern Irish youth sample. A survey conducted as part of a wider evaluation asked respondents (N = 125) their gender, self-reported well-being, and likelihood of violence. Results showed a moderating effect of gender. Higher well-being was linked to higher likelihood for violence for females, with no effects for males. This supports previous research and implies a gender-neutral approach may not reduce the risk of violence
Context-dependent effects of CDKN2A and other 9p21 gene losses during the evolution of esophageal cancer
No full textCDKN2A is a tumor suppressor located in chromosome 9p21 and frequently lost in Barrett’s esophagus (BE) and esophageal adenocarcinoma (EAC). How CDKN2A and other 9p21 gene co-deletions affect EAC evolution remains understudied. We explored the effects of 9p21 loss in EACs and cancer progressor and non-progressor BEs with matched genomic, transcriptomic and clinical data. Despite its cancer driver role, CDKN2A loss in BE prevents EAC initiation by counterselecting subsequent TP53 alterations. 9p21 gene co-deletions predict poor patient survival in EAC but not BE through context-dependent effects on cell cycle, oxidative phosphorylation and interferon response. Immune quantifications using bulk transcriptome, RNAscope and high-dimensional tissue imaging showed that IFNE loss reduces immune infiltration in BE, but not EAC. Mechanistically, CDKN2A loss suppresses the maintenance of squamous epithelium, contributing to a more aggressive phenotype. Our study demonstrates context-dependent roles of cancer genes during disease evolution, with consequences for cancer detection and patient management.</p
Wnt/β-catenin signalling underpins juvenile Fasciola hepatica growth and development
No full textInfection by the liver fluke, Fasciola hepatica, places a substantial burden on the global agri-food industry and poses a significant threat to human health in endemic regions. Widespread resistance to a limited arsenal of chemotherapeutics, including the frontline flukicide triclabendazole (TCBZ), renders F. hepatica control unsustainable and accentuates the need for novel therapeutic target discovery. A key facet of F. hepatica biology is a population of specialised stem cells which drive growth and development - their dysregulation is hypothesised to represent an appealing avenue for control. The exploitation of this system as a therapeutic target is impeded by a lack of understanding of the molecular mechanisms underpinning F. hepatica growth and development. Wnt signalling pathways govern a myriad of stem cell processes during embryogenesis and drive tumorigenesis in adult tissues in animals. Here, we identify five putative Wnt ligands and five Frizzled receptors in liver fluke transcriptomic datasets and find that Wnt/β-catenin signalling is most active in juveniles, the most pathogenic life stage. FISH-mediated transcript localisation revealed partitioning of the five Wnt ligands, with each displaying a distinct expression pattern, consistent with each Wnt regulating the development of different cell/tissue types. The silencing of each individual Wnt or Frizzled gene yielded significant reductions in juvenile worm growth and, in select cases, blunted the proliferation of neoblast-like cells. Notably, silencing FhCTNNB1, the key effector of the Wnt/β-catenin signal cascade led to aberrant development of the neuromuscular system which ultimately proved lethal - the first report of a lethal RNAi-induced phenotype in F. hepatica. The absence of any discernible phenotypes following the silencing of the inhibitory Wnt/β-catenin destruction complex components is consistent with low destruction complex activity in rapidly developing juvenile worms, corroborates transcriptomic expression profiles and underscores the importance of Wnt signalling as a key molecular driver of growth and development in early-stage juvenile fluke. The putative pharmacological inhibition of Wnt/β-catenin signalling using commercially available inhibitors phenocopied RNAi results and provides impetus for drug repurposing. Taken together, these data functionally and chemically validate the targeting of Wnt signalling as a novel strategy to undermine the pathogenicity of juvenile F. hepatica.<br/
Multiple-target detection in cell-free massive MIMO-assisted ISAC
No full textWe propose a distributed implementation of integrated sensing and communication (ISAC) underpinned by a massive multiple input multiple output (CF-mMIMO) architecture without cells. Distributed multi-antenna access points (APs) simultaneously serve communication users (UEs) and emit probing signals towards multiple specified zones for sensing. The APs can switch between communication and sensing modes, and adjust their transmit power based on the network settings and sensing and communication operations’ requirements. By considering local partial zero-forcing and maximum-ratio-transmit precoding at the APs for communication and sensing, respectively, we first derive closed-form expressions for the spectral efficiency (SE) of the UEs and the mainlobe-to-average-sidelobe ratio (MASR) of the sensing zones. Then, a joint operation mode selection and power control design problem is formulated to maximize the SE fairness among the UEs, while ensuring specific levels of MASR for sensing zones. The complicated mixed-integer problem is relaxed and solved via a successive convex approximation approach. We further propose a low-complexity design, where the AP mode selection is designed through a greedy algorithm and then power control is designed based on this chosen mode. Our findings reveal that the proposed scheme can consistently ensure a sensing success rate of 100% for different network setups with a satisfactory fairness among all UEs.<br/
A systematic review of the effectiveness of digital cognitive assessments of cognitive impairment in Parkinson’s disease
No full textBackground: Digitalization in healthcare has been extended to how we examine and manage Parkinson’s Disease Mild Cognitive Impairment (PD-MCI). Methods: Moyer Population (those with PD and in some cases control groups), Intervention (digital cognitive test) and Outcome (validity and reliability) (PIO) and Campbell et al. Synthesis Without Meta-analysis (SWiM) methods were employed. A literature search of MEDLINE, PsycINFO, CINAHL, OpenGrey, and ProQuest Theses and Dissertations Sources screened for articles. Results: The digital trail-making test (dTMT) was the most used measure. There was strong validity between the dTMT and pencil-paper TMT, Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA) scores (ranging from r = .55 to .90, p < .001). Validity between the TMT pencil-paper and digital versions were adequate (ranging from r = .51 to 90, p < .001). Reliability was demonstrated between PD and control groups’ scores (ranging from r = .71 to .87). One study found excellent inter-rater reliability (ICC = .90 to .95). The dMoCA was the most used screen that assessed more than two cognitive domains. There was a range in the strength of agreement between digital and pencil-paper versions (ICC scores = .37 to .83) and only one study demonstrated adequate validity (r = .59, p < .001). Poor internal consistency (α = .54) and poor test re-test reliability (between PD and control groups’ scores, p > .05) were found. Conclusion: This review found that digitalized cognitive tests are valid and reliable methods to assess PD-MCI. Considerations for future research are discussed.<br/
SAPP: Student Academic Performance Predictor
No full textPost COVID-19 pandemic, the education system has significantly shifted towards blended and hybrid learning approaches. In most cases, course delivery and materials are now being hosted online through various Learning Management Systems (LMS). In the recent years, researchers in the education paradigm have proposed methodologies to find key performance indicators from the LMS data and used Machine Learning (ML) models to identify students who require an early intervention to improve their academic performance. Although these ML-based solutions show high accuracy, these solutions are often restricted to a single course/module belonging to a specific department or university. Moreover, they evaluate a fixed set of ML models to determine the best performer. To address this, we propose a dynamic Student Academic Performance Predictor (SAPP) tool which can work for different types of modules having diverse student records. The tool can predict poorly performing students to make early intervention and improve their academic performance. As proof of concept, the tool has been designed as a Python application which can take LMS data from different modules and predict a list of students requiring early intervention. The application uses the best performing ML model out of 18 ML models. Initial results using LMS data collected from two different modules running at a UK university give us early indication that the SAPP tool can accurately predict student performance for various modules with diverse range of students
Process evaluation of Project Daire: a food environment intervention that impacted food knowledge, wellbeing and dietary habits of primary school children
No full textBackgroundProject DAIRE was a randomised-controlled, factorial design trial which aimed to improve children’s health-related quality of life, wellbeing, food knowledge and dietary habits via two multi-component interventions: Nourish and Engage. Nourish was an intervention aiming to alter the school food environment, provide food-based experiences and expose pupils to locally produced foods. Engage was an age-appropriate cross-curricular food education intervention incorporating food, agriculture, nutrition science and related careers. The purpose of this study was to conduct a process evaluation to evaluate DAIRE implementation, mechanisms of impact (MOI) and context to elucidate trial results, and inform scalable implementation of the DAIRE approach for successful future rollout.MethodsThe Medical Research Council’s (MRC) framework for process evaluation was followed. Formal (questionnaires designed for process evaluation) and informal (researcher records and communications) methods were used to collect quantitative and qualitative data during the DAIRE trial in relation to process evaluation. Quantitative data were analysed using descriptive statistics and qualitative data via thematic analysis to identify key themes.ResultsFifteen schools and 983 pupils (n = 495 6–7 year olds/Year 3 and n = 488 10–11 year olds/Year 7) were recruited for the 6-month DAIRE intervention; a 100% retention rate was observed at the school level and the interventions had a high level of pupil and teacher acceptability. Nourish schools delivered a higher mean dose of intervention elements (61.4%) than Engage (50%) schools but, overall, mixed implementation of both interventions occurred. DAIRE produced change through four key MOI: social learning, experimental learning, interactive engaging content and real-life connections. Lack of time was the main contextual barrier to implementation and lack of financial cost to schools indicated as a potential facilitator.ConclusionsThis process evaluation helped to identify important findings related to implementation, MOI and context. The most effective elements of the interventions which should be maintained include provision of interactive and engaging intervention elements at no financial cost to the school. Findings also identified suggestions for improvement including provision of increased teacher training, support and planning time, content reduction to facilitate easy integration, and implementation across the full academic year. A sustainable funding and resourcing mechanism is required for successful future roll-out across the UK and beyond.Trial registrationsThe original trial referenced in this process evaluation is registered as follows: National Institute of Health (NIH) U.S. National Library of Medicine Clinical Trials.gov (ID: NCT04277312; retrospectively registered 11th February 2020).<br/
Permission to screen? American sexual hygiene pictures, British censorship and local film culture 1919 – 1950
No full textThis article explores a selection of US sexual hygiene films exhibited in Britain from 1919 to 1950. Denied exhibition certificates by the British Board of Film Censors due to their propagandistic qualities, they were passed to local licencing authorities. With their combination of sermonising morality and medical ‘fact’ as well as their patronage by moral purity and welfare groups, films including Damaged Lives (1933), Birth of a Baby (1938) and Street Corner (1948) were unlikely box office successes. Drawing on local council records, this work situates these films within debates about control of film and the cinema space.<br/