Nonequilibrium interacting systems can evolve to exhibit large-scale structure and order. In two-dimensional turbulent flow, the seemingly random swirling motion of a fluid can evolve toward persistent large-scale vortices. To explain such behavior, Lars Onsager proposed a statistical hydrodynamic model based on quantized vortices. Here, we report on the experimental confirmation of Onsager's model. We dragged a grid barrier through an oblate superfluid Bose-Einstein condensate to generate nonequilibrium distributions of vortices. We observed signatures of an inverse energy cascade driven by the evaporative heating of vortices, leading to steady-state configurations characterized by negative absolute temperatures. Our results open a pathway for quantitative studies of emergent structures in interacting quantum systems driven far from equilibrium.
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http://dx.doi.org/10.1126/science.aat5793 | DOI Listing |
Glob Chang Biol
January 2025
Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, University of Goettingen, Göttingen, Germany.
Carbon use efficiency (CUE) of microbial communities in soil quantifies the proportion of organic carbon (C) taken up by microorganisms that is allocated to growing microbial biomass as well as used for reparation of cell components. This C amount in microbial biomass is subsequently involved in microbial turnover, partly leading to microbial necromass formation, which can be further stabilized in soil. To unravel the underlying regulatory factors and spatial patterns of CUE on a large scale and across biomes (forests, grasslands, croplands), we evaluated 670 individual CUE data obtained by three commonly used approaches: (i) tracing of a substrate C by C (or C) incorporation into microbial biomass and respired CO (hereafter C-substrate), (ii) incorporation of O from water into DNA (O-water), and (iii) stoichiometric modelling based on the activities of enzymes responsible for C and nitrogen (N) cycles.
View Article and Find Full Text PDFACS Omega
January 2025
Department of Chemistry, School of Natural Sciences, National University of Sciences and Technology, H-12, Islamabad 44000, Pakistan.
Implementing a hydrogen economy on an industrial scale poses challenges, particularly in developing cost-effective and stable catalysts for water electrolysis. This study explores the catalytic potential of selenium nanoparticles (Se-NPs) synthesized via a simple chemical bath deposition method for electrochemical and photoelectrochemical (PEC) water splitting. The successful fabrication of Se-NPs on fluorine-doped tin oxide (FTO) electrodes has been confirmed using a wide range of analytical tools like X-ray diffraction, energy-dispersive X-ray spectroscopy, and scanning electron microscopy.
View Article and Find Full Text PDFSci Data
January 2025
Institute for the Interdisciplinary Study of Language Evolution (ISLE), University of Zurich, Zürich, Switzerland.
The increasing availability of cross-linguistic databases dedicated to documenting morphosyntactic, lexical and phonological features has proliferated the use of such data for studies on language evolution and human history. However, most of these databases were not designed to ensure independence of features, such that it is not valid to jointly use all their features in large-scale statistical analyses assuming independence of inputs. Here, we curate published data from five large linguistic databases to generate two global-scale cross-linguistic datasets: GBI (from the Grambank dataset), and TLI (using inputs from the World Atlas of Language Structures, AUTOTYP, PHOIBLE and Lexibank).
View Article and Find Full Text PDFNat Ecol Evol
January 2025
Department of Biology, University of Turku, Turku, Finland.
Understanding factors influencing community resilience to disturbance is critical for mitigating harm at various scales, including harm from medication to gut microbiota and harm from human activity to global biodiversity, yet there is a lack of data from large-scale controlled experiments. Factors expected to boost resilience include prior exposure to the same disturbance and dispersal from undisturbed patches. Here we set up an in vitro system to test the effect of disturbance pre-exposure and dispersal represented by community mixing.
View Article and Find Full Text PDFBiol Rev Camb Philos Soc
January 2025
Wildlife Observatory of Australia (WildObs), Queensland Cyber Infrastructure Foundation (QCIF), Brisbane, Queensland, 4072, Australia.
Camera traps are widely used in wildlife research and monitoring, so it is imperative to understand their strengths, limitations, and potential for increasing impact. We investigated a decade of use of wildlife cameras (2012-2022) with a case study on Australian terrestrial vertebrates using a multifaceted approach. We (i) synthesised information from a literature review; (ii) conducted an online questionnaire of 132 professionals; (iii) hosted an in-person workshop of 28 leading experts representing academia, non-governmental organisations (NGOs), and government; and (iv) mapped camera trap usage based on all sources.
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