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K-feldspar megacrysts are common in silicic plutons, but there is a long-running debate around how they form and what their presence tells us about magmatic systems. Field, textural, and geochemical evidence supports growth in a melt-rich environment, but experimental evidence and phase-equilibria modeling indicate that K-feldspar grows late in the crystallization sequence, when the magma is highly crystalline. We provide a new perspective on this problem by examining the arrangement of plagioclase inclusions within megacrysts to test whether they exhibit the systematic low-energy crystallographic relationships expected from attachment by synneusis in melt-rich environments where crystals have space to rotate. We use electron backscatter diffraction to quantify the crystal orientations and find that the megacrysts’ plagioclase inclusions do occupy these preferred orientations and therefore were incorporated in a melt-rich environment. K-feldspar is also present as an interstitial network, but plagioclase crystals hosted within this network have non-systematic orientations. This transition from systematic to non-systematic plagioclase orientations marks the point at which the crystals formed a rigid, interconnected framework that impeded rotation into lowenergy orientations. Phase-equilibria modeling indicates that this transition occurred when the magma was ∼55% crystalline. The remaining ∼45% melt crystallized at the eutectic, forming the interstitial phases. Thus, we resolve the “megacryst paradox”; the megacrysts grew freely in melt, and the groundmass K-feldspar formed after crystal lock-up. Megacrysts therefore provide a detailed textural and chemical record of a critical period in the system’s evolution: the transition from a mobile and potentially eruptible magma to an immobile mush. [ABSTRACT FROM AUTHOR]

The article focuses on the role of nurses in the prevention and management of diabetes, a growing global health concern. Topics discussed include advancements in diabetes care technology, the importance of patient education and empowerment, and the need for holistic, person-centered care to improve patient outcomes.

Reef, R. and Gordon, C., 2024. Allometric equations for aboveground biomass estimation of temperate mangroves using uncrewed aerial vehicles. Journal of Coastal Research, 40(3), 474–484. Charlotte (North Carolina), ISSN 0749-0208. Temperate mangrove ecosystems face different stresses compared with their tropical counterparts, resulting in reduced extent, biodiversity, and productivity. Temperate mangroves represent less than 2% of global mangrove cover and are thus less studied, but where they occur, they provide distinct ecosystem services and are expanding. Avicennia marina subsp. australasica is the sole mangrove species found in Victoria, Australia, where mangroves reach their highest latitudinal limit globally. Estimating aboveground biomass (AGB) in temperate mangroves poses challenges because of their morphological differences from tropical forests. This study used uncrewed aerial vehicle (UAV)–derived measurements and ground inventory data to develop allometric equations for A. marina at its latitudinal limit. A hybrid allometric equation, incorporating both field- and UAV-derived metrics, provided the most accurate prediction of AGB (coefficient of determination [R2] = 0.93). An allometric equation using solely UAV-derived inputs (canopy area and canopy height) had high-fidelity prediction capacity (R2 = 0.85), although it overestimated AGB by 11%. A significant finding was the simplification of scaling from individual tree AGB to landscape-scale AGB by eliminating the need to segment individual tree canopies. Landscape-scale AGB estimates showed a stable underestimation of approximately 30%, which could be improved by segmenting the area into zones of similar height. AGB of mangroves in Western Port was estimated at 48 t ha–1, which is within the range measured for temperate mangroves around the world. The biomass density in this temperate region is significantly lower (40%) than the continental average. [ABSTRACT FROM AUTHOR]

Glenda Cook, Jane Murray and Charlotte Gordon discuss the challenges that care homes face when caring for residents who have dementia, type 2 diabetes and physical frailty in warm weather. [ABSTRACT FROM AUTHOR]

Aims Background Methods Results Conclusion Implications for nursing and nursing policy To profile the characteristics of nurses with varying levels of vaccine hesitancy toward the COVID‐19 and influenza vaccines.In many countries across the world, healthcare workers, and nurses in particular, display significant reluctance toward COVID‐19 and influenza vaccines due to concerns about safety, distrust in healthcare policies, and media influences. To address this, a proposed approach involves profiling nurses to tailor vaccination campaigns and to improve acceptance rates and public health outcomes.This cross‐sectional study adopted the Vaccination Attitudes Examination scale to assess hesitancy toward COVID‐19 and influenza vaccines among 294 registered nurses in the UK between March and July 2023. A K‐means cluster analysis was performed. The Strengthening the Reporting of Observational Studies in Epidemiology guidelines were adopted.Three profiles were identified. Profile A showed low vaccination hesitancy, profile B showed average hesitancy, and profile C showed high hesitancy toward vaccines. The highest concern for all profiles was related to unforeseen future effects of vaccination. Profile C had more nurses in early career roles, whereas nurses in profiles A and B were in more senior roles. Profile A showed higher educational attainment. Nurses in profile C used Snapchat more, whereas nurses in profile A used Twitter more frequently.This study identified specific characteristics associated with higher levels of vaccination hesitancy in nursing. Unforeseen future effects of vaccination are a core aspect to consider in promoting vaccination.Policies and vaccination campaigns should be targeted on early career nurses and should deliver tailored messages to dispel misinformation about unforeseen future effects of vaccination through specific social media platforms. Senior nurses should be involved as role models in promoting vaccination. These results are key for enhancing an evidence‐based approach to implementing global health policies in healthcare. [ABSTRACT FROM AUTHOR]