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Intersectional inequalities in neighbourhood air pollution concentration in England: A quantitative analysis of ecological data using Eco-Intersectional Multilevel (EIM) modelling
No full textAir pollution is detrimentally associated with many health outcomes, yet its impacts are not equally distributed. Research consistently finds inequalities by ethnicity, area deprivation and age. However, such inequalities are typically investigated separately, potentially underestimating the extent of differential exposures. We aim to investigate inequalities in NOx concentrations across multiple intersecting neighbourhood characteristics in England simultaneously. We do this using the novel Eco-Intersectional Multilevel (EIM) modelling approach, we define analytic “strata” of neighbourhoods based on sociodemographic characteristics. This enables us to quantify NOx concentration inequalities across community types, simultaneously considering area deprivation, ethnicity, education, rurality and age of residents. We find that neighbourhoods belonging to the “most deprived, high proportion minority ethnic, high education, urban and not ageing” stratum had the highest average NOx concentration. This concentration was five times higher than places with the lowest concentration in the mid deprivation, low proportion minority ethnic, high education, rural and ageing stratum. We find clear and striking inequalities by ethnicity. However, we do not find evidence of inequalities by area deprivation that operate independently of community ethnicity, likely due to the strong relationship between ethnicity and deprivation distributions. This study demonstrates the value of taking an intersectional approach to geographical inequalities
Ferroelectric Fluids for Nonlinear Photonics: Evaluation of Temperature Dependence of Second-Order Susceptibilities
No full textFerroelectric nematic fluids are promising materials for tunable nonlinear photonics, with applications ranging from second harmonic generation to sources of entangled photons. However, the few reported values of second-order susceptibilities vary widely depending on the molecular architecture. Here, we systematically measure second-order NLO susceptibilities of five different materials that exhibit the ferroelectric nematic phase, as well as the more recently discovered layered smectic A ferroelectric phase. The materials investigated include archetypal molecular architectures as well as mixtures showing room-temperature ferroelectric phases. The measured values, which range from 0.3 to 20 pm V−1, are here reasonably predicted by combining calculations of molecular-level hyperpolarizabilities and a simple nematic potential, highlighting the opportunities of modelling-assisted design for enhanced NLO ferroelectric fluids
Politicised Changes to the NICE Threshold Risk Making Cost-Effectiveness Analysis Performative, Not Informative
No full textPlant traits as potential drivers of timber value in the Dipterocarpaceae
No full textSoutheast Asian tropical forests are vital sources of high-value timber and non-timber forest products (NTFPs). This study investigates the relationship between plant traits, wood density, and timber market value within the Dipterocarpaceae family, a critical contributor to the global tropical timber trade and a key structural component of many forests in Southeast Asia. Using a phylogenetic approach, we explored the correlation of morphological and life-history traits with timber price. Our results show that wood density is significantly associated with higher timber prices, and this relationship is strongly influenced by phylogenetic dependence. We found no evidence linking timber value to the conservation status of dipterocarp species, suggesting that economic exploitation does not necessarily correlate with species endangerment. These findings emphasize the importance of understanding the evolutionary patterns driving economically valuable traits in timber species, which can guide sustainable forest management and conservation strategies in Southeast Asia
Influence of particle morphology and solvent choice on the sublimation of recrystallised ibuprofen at ambient pressure and sub-melting temperatures
No full textThe tendency of ibuprofen to sublimate can undermine content uniformity and cause caking during storage, resulting in significant economic losses. While previous studies have predominantly investigated typical evaporation under vacuum, the solvent-mediated relationship between crystal structure, sublimation kinetics and thermodynamics under practical conditions remains unclear. This study aimed to determine how crystallisation solvent governs ibuprofen sublimation under ambient pressure and sub-melting temperatures, independent of particle size, by linking crystal structure and morphology to sublimation behaviour. Ibuprofen was recrystallised from hexane, acetonitrile, ethanol and methanol, with composition and structure verified using FTIR and PXRD. SEM and particle size analysis quantified morphology and surface area, while sublimation kinetics were measured by TGA and DVS under storage-relevant conditions and subsequently enthalpy of sublimation and change in vapour pressure by temperature were estimated. It was found that polar-solvent crystals have higher surface energy and faster sublimation, while non-polar-solvent crystals were more stable and slower sublimation. The obtained enthalpy of sublimation was lower for polar-solvent samples and estimated change in vapour pressure by temperature aligned with literature trends. Overall, crystallisation solvent is a critical determinant of ibuprofen sublimation under storage-relevant conditions, influencing plane orientation, crystallinity and morphology. Polar solvents promote faster dissolution and potentially enhanced therapeutic performance but increase sublimation risk, whereas non-polar solvents improve storage stability at the expense of dissolution rate. These findings provide practical guidance for optimising solvent selection to balance pharmaceutical performance, stability and manufacturing efficiency
Using theories of power and place to evaluate community health promotion
No full textThere is some consensus that better ways of evaluating complex public health programmes are needed as experimental methods are limited in explaining the 'how' and 'why' of change. Methods like 'theory-of-change,' 'realist evaluation,' and 'systems evaluation' try to give a more complete picture of change by looking at the context of the programme. However, when these methods are used to study programmes that aim to reduce health inequalities, they often miss a crucial issue: how power affects people's health and engagement with programmes. This paper addresses that gap by reporting an ethnographic study of a community health promotion programme that was informed by a social theory of power (figurational sociology). When looking at how power dynamics played out in the targeted community, we could see why residents often did not trust the people running the programme, and why local status was so important to them. When programme staff understood these power dynamics, they were better able to connect with residents and help them improve their wellbeing. We argue that combining this way of looking at power with our observational approach gives us a much clearer understanding of how complex public health programmes work and why they succeed or fail in their aims
A human iPSC-based neural spheroid platform for modelling glioblastoma infiltration using high-content imaging
No full textGlioblastoma is the most aggressive adult brain tumour, characterised by resistance to therapy and high recurrence due to diffuse infiltration. We developed a physiologically relevant co-culture model, combining patient-derived glioblastoma cell lines with cortical-like neural spheroids differentiated from human induced pluripotent stem cells. Using high-content imaging, we demonstrate that GBM20 and GBM1 cell lines migrate directionally along axons toward neural spheroids in live imaging assays and infiltrate spheroids extensively in endpoint assays, unlike non-cancerous neural stem cells. A proof-of-principle drug screen identified PF 573228 (FAK inhibitor) and motixafortide (CXCR4 inhibitor) as potent suppressors of GBM20 and GBM1 infiltration, respectively. Bulk RNA sequencing revealed gene expression profiles correlating with invasive behaviour and drug sensitivity. This platform offers a valuable model for studying glioblastoma infiltration along axons and provides proof-of-principle that migration can serve as a measurable and actionable phenotype to screen therapeutic vulnerabilities in glioblastoma
Novel sustainable carbon dot as dual replacements for emulsion stabilizers and Photoinitiators in macroporous polymerized high internal phase emulsion fabrication
No full textBoth emulsion stabilizers and photoinitiators are essential components in preparing photocurable water-in-oil (w/o) Polymerized High Internal Phase Emulsions (PolyHIPEs). Conventional stabilizers like Hypermer B246 and photoinitiators like 2,4,6-Trimethylbenzoyldiphenylphosphine oxide (TPO) pose environmental and biological hazards, requiring careful removal before use in bioengineering applications. Furthermore, PolyHIPEs prepared with traditional surfactants often feature narrow pores and pore throats, limiting effective fluid and cell infiltration. As a class of easy-synthesizing and biocompatible nanoparticles, carbon dots (CDs) exhibit potential for use as emulsion stabilizers and photoinitiators. Herein, novel amphiphilic carbon dots (GW CDs) were synthesised from Gromwell root waste, a byproduct of shikonin extraction, as sustainable alternative. GW CDs demonstrated excellent emulsion-stabilizing ability, effective photoinitiating performance and superior biocompatibility. GW CDs were employed to stabilize the emulsions and successfully crosslink them under UV light to fabricate 2-ethylhexyl acrylate (EHA)- isobornyl acrylate (IBOA)- trimethylolpropane triacrylate (TMPTA) PolyHIPEs. The pore size and pore throat formation of the resulting PolyHIPEs could be effectively tuned by adjusting the GW CDs content. Compared to PolyHIPEs prepared using Hypermer B246 and TPO, the GW CD-stabilized counterparts exhibited significantly larger pore sizes and pore throats, improving fluid and cell permeability for tissue engineering applications. Additionally, GW CDs possess upconversion luminescence, pH sensitivity, and cell-imaging capabilities, further highlighting their potential in biomedical engineering and environmental science applications
Insights into the oxidation regime of diesel soot during realistic DPF regeneration
No full textOptimal DPF regeneration methodologies need detailed knowledge of soot oxidation regime under realistic engine conditions. This work experimentally explored the soot oxidation regime during DPF regeneration at inlet temperatures of 300°C and 350°C. A high-resolution transmission electron microscope (HRTEM) and a Raman spectroscopy were used to observe the structure evolution and explain the oxidation regime transformation during regeneration. Results showed that at the DPF-inlet temperature of 300°C, partial soot particles possessed localized hollow interiors with thicker boundaries at the later stage of its oxidation process, indicating the occurrence of internal burning. However, at the DPF-inlet temperature of 350°C, soot particles exhibit no voids and became more ordered over the whole soot oxidation process, which agree well with the behavior induced by surface oxidation. At the early regeneration stage under at 300°C DPF inlet temperature, soot oxidation led to the extension of micropores, increasing the accessibility of oxygen penetration to particle core. Reversely, the oxidation at higher temperature of 350°C and the late oxidation stage of 300°C consumed the micropores and shrank the primary particle size, accompanying with the oxidation-induced graphitization. Oxidation-induced disordering was interesting observed at the early stage of 300°C regeneration, with the ever shorter fringe, larger tortuosity and separation distance, and rising peak area ratio of D1 to G band. Evolutions of structure and defect sites revealed the inclination of internal burning at lower DPF regeneration temperatures, and the prevalence of surface oxidation during the overall process of higher temperatures
From symbiosis to scarcity: evaluating disruption associated with decarbonisation to circular waste materials between the UK cement and steel sectors
No full textThe UK cement and steel industries are decarbonising rapidly to meet net-zero targets. This study explores the unintended consequences of these efforts, particularly the potential disruption of industrial symbiosis between sectors. Cement production in the UK increasingly relies on ground granulated blast furnace slag (GGBS), a low carbon supplementary cementitious material (SCM). However, the shift from primary to secondary steelmaking threatens domestic GGBS supply. This research uses material flow analysis, life cycle assessment, and economic modelling to evaluate future GGBS availability, carbon intensities, and supply chain vulnerabilities. Findings indicate that although the steel sector is expected to reduce its environmental impact, this will cause the cement sector to face a potential shortfall in domestic SCMs, increasing reliance on imports through cross-sector decoupling and stagnation of decarbonisation. Addressing these challenges is vital to ensure a sustainable cross-sector supply chain and support future UK and global infrastructure resilience