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Fallen logs act as natural bridges over rivers in a tropical wet forest
No full textStreams and rivers are ubiquitous in tropical forests and can act as barriers for animal movement. This role as barriers can be modulated by connecting features like fallen logs. While logs are commonly observed across rivers, their role as natural bridges has rarely been highlighted. We used motion-activated cameras to characterize how mammals and terrestrial birds use logs across rivers and streams in the Osa peninsula, southern Costa Rica. We investigated factors that influence the frequency and probability of crossing and analyzed interactions like temporal avoidance/attraction or communication. We detected 20 terrestrial mammal species; on most detections (80%) animals used logs to get across the river. Crossing probability depended mostly on the species: species adapted to climbing like tamanduas (Tamandua mexicana), coatis (Nasua narica), and common opossums (Didelphis marsupialis) were more likely to cross than strictly terrestrial species like agoutis (Dasyprocta punctata) and pacas (Cuniculus paca). Animals also crossed logs that were wider, longer, and higher above the water. The diversity of species that used logs suggests they could be important drivers of movement, defining routes across the forest. We found evidence of temporal attraction between coatis, skunks (Conepatus semistriatus), and opossums, probably influenced by scent-marking, observed for 6 of 20 species, suggesting logs also act as inter and intra-specific communication sites. Our results provide evidence of the potential importance of logs and branches and suggest they could be critical features that influence daily movements and long-term space use of many terrestrial vertebrate species in tropical forests.<br/
Effect of fly ash, basalt fibre and attapulgite nanoclay on the fresh properties, rheology and shrinkage behaviour of printable concrete
No full textThe application of 3D concrete printing (3DCP) has attracted significant attention in the construction sector for its potential to revolutionize building processes. Unlike traditional methods, 3D printing eliminates the need for formwork, but it requires concrete mixtures with specific rheological properties to enable smooth extrusion and shape retention after printing. This study delves into the formulation of a unique blend of Portland Cement with fly ash, basalt fibre, and attapulgite nanoclay (nC) specifically tailored for 3D printing applications. This study provides new insights into the early-stage hydration kinetics and microstructural intricacies of these mixtures using techniques like X-ray diffraction and thermogravimetric analysis. This research investigates the influence of nanoclay on key properties such as initial rheological properties, structural build-up rate, setting time, the printing speed of 3D printable concrete and shrinkage properties. Microstructural analyses like XRD and TGA were conducted on a ternary system of fly ash, cement, and nanoclay, to interpret the mechanisms underlying early strength development. Standardized field-friendly testing methodologies have been adapted to suit printable concrete for 3D printing, and a framework has been introduced to gauge the rate of structural build-up using tests like cone penetration and scissometer tests. Within the scope of this study, a new cyclic unconfined uniaxial compressive testing (UUCT) process has been introduced as a tool for ascertaining the printing speed in 3DCP applications. The effects of nanoclay and basalt fibre on shrinkage properties of printed specimens, from initial plastic shrinkage to drying shrinkage over a span of 90 days, have been examined, an aspect not discussed in existing literature. The research findings highlight that incorporating up to 6 kg/m3 of nanoclay and about 2.1 kg/m3 of basalt fibre to the mix, the structural build-up rate is enhanced, permitting faster concrete printing, and reducing shrinkage post printing process.<br/
Hierarchical micro-segmentations for zero-trust services via large language model-enhanced graph diffusion
No full textIn the rapidly evolving Next-Generation Networking (NGN) era, the adoption of zero-trust architectures has become increasingly crucial to protect security. However, provisioning zero-trust services in NGNs poses significant challenges, primarily due to the environmental complexity and dynamics. Motivated by these challenges, this paper explores efficient zero-trust service provisioning using hierarchical micro-segmentations. Specifically, we model zero-trust networks via hierarchical graphs, thereby jointly considering the resource- and trust-level features to optimize service efficiency. We organize such zero-trust networks through micro-segmentations, which support granular zero-trust policies efficiently. To generate the optimal micro-segmentation, we present the Large Language Model-Enhanced Graph Diffusion (LEGD) algorithm, which leverages the diffusion process to realize a high-quality generation paradigm. Additionally, we utilize gradient ascent and Large Language Models (LLM) to enable LEGD to optimize the generation policy and understand complicated graphical features. Moreover, realizing the unique trustworthiness updates and service upgrades in zero-trust NGN, we further present LEGD-Adaptive Maintenance (LEGD-AM), providing an adaptive way to perform task-oriented fine-tuning on LEGD. Extensive experiments demonstrate that the proposed LEGD achieves 90% higher efficiency in provisioning services compared with other baselines. Moreover, the LEGD-AM can reduce the service outage time by over 50%
Engendering critical academic development
No full textThis chapter reckons with the complexities of the barriers academic women face in times of flux, division, competition and conflict. We begin by situating our concerns within a critique of the limitations and problematics of mainstream approaches to the development of academics. Against this, we offer a vision of Critical Academic Development, to serve the purposes of enabling transformative ethical leadership. Drawing from a critical review of published texts, we highlight the ways in which to orient such development, cognisant of (i) the fraught conditions for academic practice and (ii) the many unidentified risks, which impact on women academics’(iii) academic careers; (iv) teaching; (v) research; (vi) broader academic practices, and (vii) their agency to engender change. What this critical review reveals about engendering change for ethical leadership of women academics is then discussed, with consideration of the implications for such models as HERS-EA.<br/
McTaggart and Oakeley on the unreality of time
No full textJ. M. E. McTaggart’s (1866-1925) argument for the unreality of time, first published in 1908, set the decisive framework for discussions about time in 20th-century analytic philosophy. This chapter provides an outline of the argument and situates it within the wider context of McTaggart’s philosophical system. It then provides an overview of a critique of McTaggart’s philosophical views on time by Hilda Oakeley (1867-1950). Oakeley was McTaggart’s contemporary and her critiques—while firmly based within their shared commitment to idealism—prefigure many later criticisms and problems faced by 20th-century philosophers of time
The interplay of minority group members’ positive and negative intergroup contact and its implications for intergroup relations and inequality
No full textApplication of a landscape feature classification technique to historical building facades
No full textTechnological advances have led to the development of a range of non-destructive techniques for the assessment of stone decay. Of these evolving techniques, few are as extensively applied as 3D modelling for assessment of surface alteration. Many studies focus on alteration of elevation relative to a ‘baseline’ surface to determine the spatial distribution of surface change. These approaches are limited when dealing with historical stones, where through decay or architectural choices, original tool marks or base levels may not be apparent. However, these 3D scans of wall surfaces can be considered in much the same fashion as digital elevation models (DEMs) of landscape or earth surface features. Acceptance of this premise enables the application of comparative roughness assessments to determine the impact that different weathering pasts have had upon the microtopography. The study site for this work is Fitzroy Presbyterian Church in Belfast (UK). The church’s stonework was finished with a rough surface that obscures tool marks and through its ‘topographic’ complexity prevents the application of estimated geometric baselines. The church was built in stages and has been the subject of restoration campaigns, resulting in multiple wall sections of different ages and weathering histories. Two wall sections were scanned using the Konica Minolta VIVID 9i 3D scanner, creating models with submillimetre accuracy. The roughness assessment technique selected was topographic position index (TPI), a focal statistical technique developed to identify topographic features across landscapes. Using this technique, it’s possible to classify microtopographic features at a point on the wall surface.<br/
Clustering smart meter data for residential load profile analysis
No full textSmart meters typically record half-hourly electricityusage, enabling detailed analysis of household consumption patterns.However, the data is often random and high-dimensional,making pattern detection difficult. K-means clustering is appliedto a real-world smart meter dataset from a London pilotprogram, with data aggregated by season and household tosimplify analysis. The challenges of clustering time series data and selecting the optimal number of clusters are discussed. Results show that k-means can effectively group households with similar usage patterns, supporting applications in demand-side management, grid balancing, and forecasting