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Design and development of optical modules for the BUTTON-30 detector
No full textBUTTON-30 is a neutrino detector demonstrator located in the STFC Boulby underground facility in the north-east of England. The main goal of the project is to deploy and test the performance of the gadolinium-loaded water-based liquid scintillator for neutrino detection in an underground environment. This will pave the way for a future large-volume neutrino observatory that can also perform remote monitoring of nuclear reactors for nonproliferation. This paper describes the design and construction of the watertight optical modules of the experiment
Estimating the dominant frequencies of real-valued cyclic processes in natural environments for long-term operation of autonomous robots
Get PDFAutonomous mobile robot localisation, planning, and navigation methods typically rely on environmental representations. Previous research has shown that the temporal dynamics captured by specialized models help autonomous robots to operate for longer periods with better efficiency. One of the leading approaches uses maps enhanced by frequency analysis to model and predict repeating cycles of activity in the environment. However, this approach implicitly relies on prior knowledge of the expected periodicities, such as days and weeks, encoded by the human designers of the system. This paper presents a new method to automatically search the robot’s observations for dominant frequencies, leading to a more general method than the previous approach for frequency map enhancement. The proposed algorithm extends the problem definition from binary observations also to real-valued time series, making it applicable to a broader spectrum of robotic tasks. We show that the new method can be implemented in robotic systems operating without prior knowledge of the underlying processes that influence the dynamics of the working environment across a wide variety of tasks similar to the long-standing state-of-the-art. We hypothesise that an autonomous robot using the proposed improvement can be deployed to unprecedented environments
Dielectrocapillarity for exquisite control of fluids
Get PDFSpatially varying electric fields are prevalent throughout nature, such as in nanoporous materials and biological membranes, and technology, e.g, patterned electrodes and van der Waals heterostructures. While uniform fields cause free ions to migrate, for polar fluids they simply reorient the constituent molecules. In contrast, electric field gradients (EFGs) induce a dielectrophoretic force, offering fine control of polar fluids even in the absence of free charges. Despite their vast potential for optimizing fluid behavior, EFGs remain largely unexplored at the microscopic level due to the absence of a rigorous first-principles theory of electrostriction. By integrating state-of-the-art advances in liquid state theory and deep learning, we reveal how EFGs modulate fluid structure and capillarity. We demonstrate that dielectrophoretic coupling enables tunable control over the liquid–gas phase transition, capillary condensation, and fluid uptake into porous media. Our findings establish “dielectrocapillarity”—the use of EFGs to manipulate confined fluids—as a powerful mechanism for controlling volumetric capacity in nanopores, holding immense potential for energy storage, selective gas separation, and tunable hysteresis in neuromorphic nanofluidics. Furthermore, by linking nanoscale dielectrocapillarity to macroscopic dielectrowetting, we establish a foundation for field-controlled wetting and adsorption phenomena of polar fluids across length scales
Ubiquitin‐like SUMO protease expansion in rice ( Oryza sativa L.)
Get PDFPlain Language Summary: Plants require a process called SUMOylation to grow properly and respond to stresses. We used bioinformatic tools to study a group of proteins involved in SUMOylation, known as SUMO proteases (Ubiquitin‐Like Proteases), which help regulate this process in cultivated Asian rice, and compared them with those in wild relatives of rice. We found that these genes have increased in number in cultivated rice, possibly as a result of breeding. These proteins also play important roles in helping rice cope with different types of stress, such as salt and drought stresses. Our findings may contribute to improving rice breeding in the future
Supersymmetry and integrability of the elliptic AdS 3 × S 3 × T 4 superstring
Get PDFWe construct a 1-parameter family of Ramond-Ramond fluxes supporting the elliptic AdS3 × S3 × T4 metric with constant dilaton and preserving 8 of the 16 supercharges of the undeformed background. On the supersymmetric locus, we compute the tree-level worldsheet S-matrix in uniform light-cone gauge up to quadratic order in fermions and find that it non-trivially satisfies the classical Yang-Baxter equation. Moreover, imposing classical integrability and symmetries, we conjecture compatible processes quartic in fermions. We also investigate different limits of interest, including trigonometric deformations and the limit to the AdS2 × S2 × T6 superstring. Our results provide strong evidence for a supersymmetric and integrable elliptic deformation of the AdS3 × S3 × T4 superstring supported by Ramond-Ramond flux and a constant dilaton
The “I” in egalitarianism: Hadza hunter-gatherers averse to inequality primarily when personally unfavorable
Get PDFMany economists contend that humans have strong, universal, other-regarding equality preferences with deep evolutionary roots. Indeed, many hunter-gatherers have endemic food-sharing and proscriptions against accumulation. These “egalitarian” practices appear superficially consistent with intrinsic equality preferences. Previous experiments, involving donating positive endowments to strangers, seldom match the redistributive equality observed in real-world sharing. Such methods ignore the role of taking, and do not capture sharing dynamics among differentially wealthy campmates. This study, instead, uses a one-player “give-or-take” experiment, with real campmates as recipients, better emulating real-world forager food redistribution. We asked 117 Hadza participants, privately, to redistribute food resources between themselves and a campmate after receiving advantageous and disadvantageous endowments. Although few participants were wholly self-interested, most did not seek general equality. Instead, most tolerated inequality when it benefited them but not when it benefited others. Given advantageous endowments, a minority (40.9%) chose to give, while 30% exacerbated inequality by taking more. Given disadvantageous endowments, many took more than necessary to achieve equality. The modal decision across tasks was to take everything. Only when participants could take from others did results approximate real-world sharing patterns. Findings suggest that intrinsic, private other-regarding fairness preferences need not underlie widespread forager food-sharing, which could be maintained by others’ self-motivated demands or extrinsic fairness norms. We also found that men and younger people were more willing to give away advantageous endowments. Further, we found that individuals with greater exposure to cultures outside Hadzaland were more accepting of unfavorable inequality, suggesting that marketization might promote disadvantageous inequality tolerance
Exploring Size-Controlled Exciton Evolution Using DNA Libraries
Get PDFTo investigate multichromophore phenomena, progress traditionally relies on model covalent dimers for spectroscopic interrogation. Integrating molecular semiconductors into nucleic acid libraries can enable rapid screening of multichromophore phenomena. Here, we report DNA-directed assembly of up to five π-conjugated chromophores that demonstrate charge separation and electronic delocalization phenomena. We integrate a range of porphyrins and perylene diimides (PDIs)molecular semiconducting materials widely used in organic electronic devicesin DNA, encoding nearest-neighbor assembly through base-sequence programmed hybridization. In this way, we can assemble multicomponent stacks with tailored electronic properties from a central chromophore-DNA library. This allows dimer and multimer production on demand, within hours, from presynthesized DNA-chromophores for spectroscopic analysis. We demonstrate the library’s ability to optimize for charge transfer, computationally prescreening for close π-stacking as a proxy for large orbital overlap and exchange energy. Our modular DNA assembly reveals opportunities for rapid development of simple, bespoke chromophore architectures with stoichiometric chromophore control and ordering
Shifting baselines increase the risk of misinterpreting biodiversity trends
Get PDFEcological studies quantifying the impact of land-use change on biodiversity may be sensitive to the choice of reference points – or baselines – particularly when sampling across human land-use gradients and other space-for-time comparisons. Much depends on whether the chosen baseline has already undergone shifts in species composition because of hunting, habitat loss and degradation. However, few studies have assessed the influence of shifting baselines on estimates of anthropogenic impacts. Using new survey data from five West African land-use gradients, we examine how habitat patch size and structure influences the estimated impact of land-use change on bird species richness and functional diversity. We show that smaller forests have already lost many forest-dependent birds, particularly those with large body size or specialised ecological niches, leading to reduced estimates of biodiversity loss after deforestation. The steepest biodiversity loss was found in mid-sized forests whereas relatively shallow declines were estimated for the most extensive forests – despite their richer taxonomic and functional diversity. In these larger forest blocks, accurate estimates of biodiversity loss may require longer transects extending beyond the biodiversity ‘shadow' caused by the more extensive spillover of forest species into the surrounding landscape, potentially linked to source–sink dynamics. These findings suggest that biodiversity assessments are highly sensitive to baseline selection and transect design, highlighting the risk of underestimating land-use impacts unless shifting baselines are carefully considered
Directed Spatial Permutations on Asymmetric Tori
No full textWe investigate a model of random spatial permutations on two-dimensional tori, and establish that the joint distribution of large cycles is asymptotically given by the Poisson--Dirichlet distribution with parameter one. The asymmetry of the tori we consider leads to a spatial bias in the permutations, and this allows for a simple argument to deduce the existence of mesoscopic cycles. The main challenge is to leverage this mesoscopic structure to establish the existence and distribution of macroscopic cycles. We achieve this by a dynamical resampling argument in conjunction with a method developed by Schramm for the study of random transpositions on the complete graph. Our dynamical analysis implements generic heuristics for the occurrence of the Poisson--Dirichlet distribution in random spatial permutations, and hence may be of more general interest
Taphonomic impact on human remains in rapidly changing glacial environments: current insights and future directions
Get PDFGlaciers worldwide are undergoing accelerated down-wasting and retreat due to a warming climate, increasingly leading to the melt-out and exposure of human remains, either from past epochs, or of forensic significance, in alpine environments. In the context of the UN’s 2025 Year of Glaciers’ Preservation, the impact of glacier retreat on the preservation and analysis of human remains is studied. Exposed human remains need to be thoroughly documented and recovered in a swift and effective manner to prevent information loss, which can affect the identification and post-mortem analysis of individuals. To better manage the retrieval and analysis of these remains, an understanding of the taphonomic alterations brought about by the glacial environment needs to be established. The existing knowledge of the intersection between human remains and changing glacial environments is reviewed according to the published literature and case studies, with the goal of identifying any challenges and gaps in current understanding. Finally, future research in this emerging field, including the unique taphonomy associated with glaciers, the ephemeral nature of the archaeological material, methods of predicting the location of remains, and best practice for their timely recovery, are identified and discussed
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