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Giant injectite complex sand body architecture in the Late Jurassic East Greenland rift
No full textThe geometries of kilometre-scale sandstone injectite complexes, and the models developed for their emplacement, are based on a scarce dataset of Large Sandstone Intrusion Complexes (LSICs). The Hareelv Formation of the Jameson Land Basin (East Greenland) provides the best outcrop example of a large-scale (>4,000 km2) injectite complex within an extensional tectonic setting found globally. Using 3D photogrammetric models and field observations, the large-scale geometries of the Hareelv Formation injectite sand bodies are characterised, and a new model for closed system injectite complexes is proposed. The Hareelv Formation sand bodies are up to 50 m thick and 1-2 km wide. Common features include steps, low-angle discordant wings, host rock rafts, bifurcations, linking-complexes and stockworks. No physical evidence for linkage to the palaeoseabed, or candidate parent units. is present. Therefore, the Hareelv Formation injectites are inferred to have acted as a closed system: self-sourced and dominated by lateral injection. The distribution of the sealing organic rich, laminated host mudstones exerts a primary control on the development of injectites in the Jameson Land Basin and adjacent regions. The self-sourced lateral intrusion processes may provide a more appropriate mechanism for the interpretation of subsurface examples where identification of source units has been uncertain
Multiscale geometric analysis of dynamic wettability on complex, fractal-like, anisotropic surfaces
No full textThis study introduces novel insights into the development of procedures for identifying the most relevant scales for observing the interactions of dynamic wettability and surface complexities. The experimental procedures presented for measuring dynamic contact angle hysteresis in multiscale correlation with the geometric characteristics of anisotropic surfaces contribute to a new perspective on measurement practice. In this study, microtexturing with a pyramidal structured abrasive belt is applied for precisely forming area- and length-scale anisotropic surface complexities, and consequently, topographically dependent functional features. The significant role of anisotropic topographies in modeling dynamic wettability behavior is highlighted through multiscale measurement-based analysis. These studies verify the relationship between dynamic wettability and the finest surface microgeometry (microroughness) and also the coarsest texture components (waviness). The size of topographic features, ranging from microroughness to waviness, significantly influences droplet pinning and liquid entrapment. Furthermore, the influence of material hydrophilicity and hydrophobicity on the calculated multiscale relationships is assessed. The results indicated specific scales that best correlate with dynamic wettability, with length- and area-scale complexities of 6.9 µm and 28 µm2, respectively. A novel measurement-based approach to scale-dependent surface–functionality interactions offers new insights for designing dynamic wettability on anisotropic surfaces
Eyring–Polanyi Rate Theory for the Homogeneous Nucleation of Organic Crystals from Solution
No full textUsing elementary concepts of chemical reaction kinetics, the rates of primary homogeneous organic crystal nucleation from supersaturated solutions are modeled as nucleation with first order kinetics from large solute density fluctuations (LSDFs). Solute density fluctuations are modeled as diffusively driven many-body collisions of weakly interacting solvated solute molecules. The first order rate constant is a system-specific supersaturation-independent rate constant for nucleation in LSDFs. It is shown for several solute–solvent systems that the temperature-dependence of this nucleation rate constant exhibits Arrhenius behavior. The activation enthalpy (ΔH⧧) and activation entropy (ΔS⧧) for homogeneous nucleation is determined from an Eyring–Polanyi analysis of temperature-dependent nucleation rates. The steps of the Eyring–Polanyi analysis are described in detail for the homogeneous nucleation of l-histidine from aqueous solutions. The analysis is also applied to temperature-dependent homogeneous nucleation rates of salicylic acid in four different solvents. For all systems, the supersaturation- and the temperature-dependence of the primary homogeneous nucleation rates are completely reproduced by reference to temperature-dependent solubility data through the activation parameters ΔH⧧ and ΔS⧧. ΔH⧧ is for all examined systems approximately 12 times the enthalpy of solution determined from solubility data, suggesting that nucleation from LSDFs resembles, at the molecular level, a reverse dissolution process. Within the temperature ranges used for measuring nucleation rates, the Gibbs energy of activation ΔG⧧ does not vary strongly, resulting in an inverse correlation between enthalpies and entropies of activation. The Eyring–Polanyi framework thus provides, for the first time, a method for semiquantitative predictions of homogeneous nucleation rates from temperature-dependent solubilities
Working with a youth mental health apprenticeship scheme to coproduce evidence synthesis: The youth mental health evidence synthesis hub.
No full textRethinking consumer convenience as a barrier to reusable packaging systems
No full textReusable packaging systems have been recognised as a part of sustainability and circular economy transitions but they are widely considered to be inconvenient for the consumer. This article challenges the notion that reuse systems are necessarily inconvenient by drawing attention to reuse practices, differences between reusable packaging systems, and associated complexes of consumption practices. Theoretical insights from studies of convenience food and meal planning are used to inform our approach to convenience and convenient practices. In the UK, recent reusable packaging trials in mainstream retail have offered consumers the opportunity to participate in reusable packaging systems as part of their otherwise ordinary consumption. Based on qualitative research conducted with reusable packaging system users participating in these trial systems and others during this time, three practice complexes are identified and examined. These are bulk buying, organisational practices and weekly shopping. The analysis of these complexes provides insight into difficult aspects of reusable packaging systems, while separating discussion of these aspects from areas which would change with system transition. This locates the niche position of reusable packaging systems within a potential transition process and reiterates the importance of considering convenience in context
Delusion as embodied emotion: a qualitatively-driven, multimethod study in first-episode psychosis in the UK
No full textUrbanMMCL: Urban region representations via multi-modal and multi-graph self-supervised contrastive learning
No full textUrban region representation learning has emerged as a fundamental approach for diverse urban analytics tasks, where each neighborhood is encoded as a dense embedding vector for effective downstream applications. However, existing approaches suffer from insufficient multi-modal alignment and inadequate spatial relationship modeling, limiting their representation quality and generalizability. To address these challenges, we propose UrbanMMCL, a novel self-supervised framework that integrates multi-modal multi-view contrastive pre-training with unified fine-tuning for comprehensive urban representation learning. UrbanMMCL employs a dual-stage architecture. First, cross-modal contrastive learning aligns diverse data modalities including remote sensing imagery, street view imagery, location encodings, and Vision–Language Model (VLM)-generated textual descriptions. Second, multi-view adaptive graph contrastive learning captures complex spatial relationships across human mobility, functional similarity, and geographic distance perspectives. The framework then fine-tunes all parameters with the learned representations for effective adaptation to downstream tasks. Comprehensive experiments demonstrate that UrbanMMCL consistently outperforms state-of-the-art methods across pollutant emission prediction, population density estimation, and land use classification with minimal fine-tuning requirements, thereby advancing foundation model development for diverse Geo-AI applications
Evaluation of a novel 4-day decellularisation protocol for porcine flexor tendons: A comparative study with a 26-day process
No full textRupture of the anterior cruciate ligament is a common sports-related injury that lacks intrinsic healing capacity, often necessitating surgical intervention. Our group has developed a new graft biomaterial, the decellularised porcine super flexor tendon (pSFT), designed to mitigate immune rejection post-implantation by removing cellular components. The current 26-day decellularisation process attenuates the mechanical properties of the graft, potentially disrupting the structural micro-cues that influence cell repopulation and integration. This study investigates a shortened 4-day protocol to determine whether mechanical properties are preserved more closely to native, unprocessed tissue.
Histological analysis and DNA quantification confirmed effective cell removal for both the 26-day and 4-day protocols. Native, 26-day processed, and 4-day processed grafts were mechanically evaluated through stress relaxation and failure testing. Following stress relaxation testing, several Maxwell-Weichert viscoelastic parameters were found to significantly differ between 26-day and native groups (E0, E1, E2 & τ2), whereas between 4-day and native groups fewer significant differences were found (E1 & E2). Following failure testing, again several parameters were found to significantly differ between 26-day and native groups (PFAIL, UTS, Elinear and εT), whereas between 4-day and native groups only one parameter was significantly different (Elinear).
These findings indicate that the 4-day decellularisation process better preserves the native tissue mechanical properties, potentially reducing structural alterations and improving suitability for anterior cruciate ligament replacement
The State of Palliative Care in Nigeria: A Scoping Review
No full textContext
Globally, about 85% of palliative care need is unmet. Africa accounts for 20% and 52% of adult and pediatric palliative care burden worldwide, respectively. Nigeria has progressing palliative care provision and meets only 0.2% of national need.
Objectives
To describe extant literature detailing palliative care knowledge, implementation, medicine availability, education, policy, vitality, and research in Nigeria, propose areas for future scientific inquiry, and inform interventional targets.
Methods
Arkey and O’Malley design for scoping reviews reported per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. PubMed, Embase, Cochrane CENTRAL, Web of Science, Scopus, and African Index Medicus were searched in January 2024 and updated in December 2024. Full-text, peer-reviewed articles in English describing palliative care in Nigeria were included.
Results
Of the 6,116 search results, 290 underwent full-text review and 59 satisfied inclusion criteria. Most studies examined palliative care knowledge, attitudes, and practices while few evaluated implementation practices or interventions. Palliative care awareness in Nigeria is low; however patients, family caregivers, and healthcare professionals have expressed interest in expanded education, infrastructure, and culturally-appropriate delivery models. Persistent challenges include opioid availability, delayed referral, inconsistent education, insufficient institutional and federal policy, and absent professional validation.
Conclusions
The gaps in palliative care in Nigeria identified by this review can inform interventional targets for national acceptance and equitable delivery. It is critical to prioritize multi-level policy changes to expand access to high-quality palliative care services and mitigate the growing burden of suffering among the seriously ill