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Controls on spatial heterogeneity in dinoflagellate cyst distribution in recent sediments off West Antarctica.

Here we present the study of 48 new dinoflagellate cyst assemblages from the west Antarctic shelf sediments on a wide longitudinal scale, with a greater representation of ice-proximal sites, and provide a comprehensive overview of their distributional patterns and multiple environmental forcing factors. We find a strong spatial heterogeneity in the dinoflagellate cyst distribution patterns; 1) the northern Antarctic Peninsula region is dominated by Islandinium? minutum, Selenopemphix antarctica and Brigantedinium spp. in association with meltwater-induced stratification and high diatom productivity, 2) the Bellingshausen-Amundsen Seas is dominated by Gymnodinium microreticulatum and Selenopemphix sp. 1, under influences of strong offshore winds, unstable water column and Phaeocystis blooms in austral summer, and 3) the Ross Sea shows an extreme contrast - the east-central region under vigorous vertical mixing and high Phaeocystis production is dominated by Selenopemphix sp. 1, while the western side with high sea-ice concentration and sea-ice derived meltwater stratification is dominated by Polarella glacialis cysts together with Nucicla umbiliphora, I.? minutum and Cryodinium meridianum. The robust along-shelf separations of the dinoflagellate cyst species compositions highlight melt-related hydrodynamic-meteorological coupling processes around maritime Antarctica that control physico-biological properties and overall microplankton communities therein. As the ice-shelf disintegration and sea-ice loss continue, there will be a fundamental reconfiguration of microplankton production and their community structures in a future Antarctic Ocean with greater open-water areas. This study highlights the potential of dinoflagellate cysts to monitor changes in hydrographic conditions and plankton communities in these sensitive polar marine ecosystems

‘Expressing inner dialogues of teaching experience: Writing as a path to emancipation and growth’

This paper explores the complexities and personal demands of entrepreneurship education (EE) teaching, emphasising the importance of writing about teaching experiences as a tool for self-exploration and professional development. Using Collaborative Auto-Ethnography (CAE), this study builds on 18 months of collaborative work, designing and delivering three Professional Development Workshops (PDWs) for entrepreneurship educators. These workshops provided inclusive spaces for educators to share, reflect, and connect with their professional identities. By centring personal narrative, this paper challenges conventional pedagogical norms and fosters self-reflective teaching practices. By drawing on the positionality of our conversations, experiences, and intellectual growth, we offer educators and scholars a processual approach to writing about their teaching experiences. This practice amplifies diverse experiences and pedagogies, contributing to a more equitable and authentic educational landscape in entrepreneurship education

Talin-tensin3 interactions regulate fibrillar adhesion formation and tensin3 phase separation.

Integrin-mediated cell-matrix adhesions regulate communication between cells and the extracellular matrix. In matrix-secreting cells, fibrillar adhesions (FBs) containing high levels of α5β1 integrins and the tensin3 adaptor protein are essential for fibronectin (FN) fibrillogenesis. Here, we demonstrate that tensin3 binds to four helical regions (R3, R4, R8, and R11) of talin, the principal integrin activator. Structural analysis revealed the residues critical for the tensin3-talin interaction, and mutational analysis showed that talin R8 and R11 are essential for FB formation and FN fibrillogenesis. Cellular experiments demonstrate that tensin3 binding to talin not only regulates integrin activation, but also modulates tensin3's propensity to undergo liquid-liquid phase separation (LLPS). Formation of such LLPS condensates increased when cells were plated on soft substrates compared with stiff ones. This effect was abolished by blocking the interaction between tensin3 and talin. Our data suggest a model in which LLPS condensates provide a signaling platform involved in cellular responses to sudden changes in tissue mechanics

Nanoscale surface morphology modifications for next-generation supercritical CO2 heat exchangers: Review and perspective

Carbon nanotube (CNT) pin fin arrays, CNT, or nanoparticle coating have emerged in recent decades as novel techniques for enhancing heat transfer and reducing drag. In this paper, the suitability of these techniques is reviewed specifically for heat transfer enhancement and drag reduction in the gas side of supercritical carbon dioxide (SCO2) counterflow tube-in-tube or plate type heat exchangers for applications in CO2 refrigeration systems. The methodology and the applicability of various approaches for predicting the heat transfer rates and the frictional pressure drop associated with flow over a nanocoated surface have been reviewed. Findings from both experimental and numerical studies highlight critical limitations, including a lack of fundamental knowledge about flow over superhydrophobic surfaces and the absence of experimental data for crucial parameters such as temperature jump at the wall, velocity and temperature shifts, and the Reynolds analogy factor for nanotube or nanoparticle coatings in turbulent flow regimes. These limitations significantly hamper the predictive capabilities of both single-scale and multi-scale models for frictional pressure drops and heat transfer coefficients. To enhance the accuracy of these models, it is essential to consider surface parameters such as arithmetic mean roughness (Ra), root-mean-square roughness (Rq), effective slope (Es), skewness (Sk), and kurtosis (ku)

Engineering an LTLf\mathsf {LTL_f} Synthesis Tool

The problem of LTLf reactive synthesis is to build a transducer, whose output is based on a history of inputs, such that, for every infinite sequence of inputs, the conjoint evolution of the inputs and outputs has a prefix that satisfies a given LTLf specification. We describe the implementation of an LTLf synthesizer that outperforms existing tools on our benchmark suite. This is based on a new, direct translation from LTLf to a DFA represented as an array of Binary Decision Diagrams (MTBDDs) sharing their nodes. This MTBDD-based representation can be interpreted directly as a reachability game that is solved on-the-fly during its construction

Wood ants on the edge: How do the characteristics of linear edges effect the population dynamics of an edge specialist?

Landscape structure modulates species dispersal by presenting barriers or opportunities. Slow-dispersing edge specialists, e.g. the northern hairy wood ant (Formica lugubris), are likely to be most affected by topography and land management practices, because they require adjacent contrasting habitats, e.g. to access both food and sunlight. In managed forests, canopy gaps are often linear and anthropogenic, such as paths, firebreaks, and roads (collectively ‘rides’), and their orientation determines shade distribution. Using data spanning 10 years, we ask how ride orientation and width affect the distribution and dispersal of three F. lugubris populations in the North York Moors, UK. Ride orientation clearly affected nest abundance, with a higher nest density on rides oriented north-south (N-S) or east-west (E-W) (cardinal directions) than on those oriented NE-SW or NW-SE (intercardinal directions). Conforming to predictions based on sunlight availability, N-S oriented rides were occupied more symmetrically than E-W ones, where the north side was used predominantly. Nests were generally larger on narrower rides. Ride orientation also clearly affected dispersal: wood ants dispersed c15 m/year along rides oriented in cardinal directions, compared with only c5 m/year on rides oriented intercardinally. Our results show that ride characteristics (width, orientation), resulting directly from forestry practices, influence the distribution and dispersal of an ecosystem engineer woodland species; this may also apply to other forest-edge specialists. As wood ants can suppress defoliating pests, these findings could benefit forest management; forest planners could encourage wood ant colonisation of plantation forest by ensuring linear features contribute to north-south and east-west connectivity

Highly variable light attenuation across a gneiss rock wall in eastern Greenland

Exposure ages and erosion rates determined using rock surface luminescence have the potential to revolutionalise Quaternary Science. However, accurately quantifying μ (the light attenuation coefficient) is a significant challenge. Our study shows how variable light attenuation properties (i.e. μ) can be for five samples taken from a small (423 m) elevation range of a near-vertical gneiss rock wall, which we would have expected to have had a shared μ value. The light attenuation properties varied on multiple scales: (i) between samples; (ii) between replicate cores; and (iii) between slices within a core. To avoid the between sample variability, we need to either measure μ directly from the rock cores used to derive the exposure age or erosion rate, or prove that these samples and the sample used to calibrate μ have identical light attenuation properties. To avoid variability between replicate cores observed in samples, it may be more accurate to derive exposure ages or erosion rates using a single core with identical light attenuation properties to the sample used to calibrate μ. Finally, where possible, we should avoid rocks that have hetergeneous mixes of minerals with different opacities (lighter and darker). However, if it is not possible, we should routinely measure red-green-blue (RGB) values to link the presence of any low datapoints in the luminescence depth profiles to overlying lighter-coloured minerals that could have caused light ‘piping’. Our findings further emphasise the detailed consideration required for deriving μ to determine accurate exposure ages and erosion rates

Preserving the microstructural fabric integrity of sand: A non-invasive gelatin-based hydrogel stabilization method

Studying the microstructure of granular materials is crucial for understanding their mechanical properties, such as the fabric in sand piles and deep-sea soils, but their susceptibility to disturbance during sampling gravely enlarges the difficulty to progression. Existing stabilization methods mainly focus on enhancing soil strength, but fail to preserve the original granular fabric, which is essential for accurate microstructural analysis. This study proposes a non-invasive stabilization method based on gelatin hydrogel, aiming to enhance the self-stability of sand while preserving its in-situ microstructure. Through vibration and consolidated undrained (CU) triaxial tests, this study systematically evaluated the effects of gelatin hydrogel concentrations ranging from 0.25 % to 1.0 % on sand stabilization at the macro scale. The results showed that the 0.5 % hydrogel-stabilized sand exhibited a volumetric strain of only 0.87 % after vibration, demonstrating significant improvement in self-stability. The shear strength of the stabilized sand was similar to untreated sand, with peak deviatoric stress of 192 kPa compared to 191 kPa, and the internal friction angle remained at 28°, indicating minimal alteration to the load-bearing structure at the macro scale. Further non-destructive microstructural analysis using CT scans and environmental scanning electron microscopy (ESEM) confirmed that the hydrogel uniformly filled pores with a 99.12 % filling rate, without altering the particle morphology or the contact network. These findings demonstrate that 0.5 % gelatin hydrogel effectively enhances the self-stability of sand while maintaining its undisturbed internal fabric, thereby providing a reliable and non-invasive approach for microstructural characterization and offering new insight into the flexible cementation mechanism of hydrogel-stabilized sands

Pore-fluid pressure pulses from rapid, localized compaction of a porous rock

Changes in pore fluid pressure are often implicated in producing a range a fault slip behaviour and in the triggering of earthquakes. For fluid pressure increases to influence fault mechanics, either low permeability materials must be present to inhibit fluid loss, or a mechanism for rapid production of pore fluid pressure must operate. In this work, we present observations of rapid generation of pulses of pore fluid pressure, by the unstable propagation of localized low porosity bands formed during compaction of porous rock. We perform a series of high pressure compaction experiments on intact cores of porous α and β -bassanite that are hydrostatically loaded at different compaction rates. We find that at hydrostatic loading rates of ≥ 0.01 MPa.s−1, pulses of pore fluid pressure are observed only for α -bassanite, associated with expulsion of fluid during the rapid formation of low porosity bands. At slower hydrostatic loading rates ( < 0.01 MPa.s−1) no pore fluid pulses are observed and compaction proceeds smoothly, despite the development of a similar network of low porosity bands in α -bassanite, suggesting that the bands propagate in a slower and more stable fashion at these conditions. We attribute the absence of pore-pressure pulses and low porosity bands in β -bassanite to differences in bassanite grain size and shape. We conclude that at high hydrostatic loading rates pore fluid pulses are produced during the rapid formation of low porosity bands when stress concentrations at the band tip reach the critical stress intensity factor K C causing unstable propagation