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Understanding spatio-temporal dynamics of biotic communities containing large numbers of species is crucial to guide ecosystem management and conservation efforts. However, traditional approaches usually focus on studying community dynamics either in space or in time, often failing to fully account for interlinked spatio-temporal changes. In this study, we demonstrate and promote the use of tensor decomposition for disentangling spatio-temporal community dynamics in long-term monitoring data. Tensor decomposition builds on traditional multivariate statistics (e.g. Principal Component Analysis) but extends it to multiple dimensions. This extension allows for the synchronized study of multiple ecological variables measured repeatedly in time and space. We applied this comprehensive approach to explore the spatio-temporal dynamics of 65 demersal fish species in the North Sea, a marine ecosystem strongly altered by human activities and climate change. Our case study demonstrates how tensor decomposition can successfully (i) characterize the main spatio-temporal patterns and trends in species abundances, (ii) identify sub-communities of species that share similar spatial distribution and temporal dynamics, and (iii) reveal external drivers of change. Our results revealed a strong spatial structure in fish assemblages persistent over time and linked to differences in depth, primary production and seasonality. Furthermore, we simultaneously characterized important temporal distribution changes related to the low frequency temperature variability inherent in the Atlantic Multidecadal Oscillation. Finally, we identified six major sub-communities composed of species sharing similar spatial distribution patterns and temporal dynamics. Our case study demonstrates the application and benefits of using tensor decomposition for studying complex community data sets usually derived from large-scale monitoring programs.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5685633 | PMC |
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0188205 | PLOS |
Artif Intell Med
September 2025
Department of Mathematics, Hangzhou Dianzi University, Hangzhou 310018, China. Electronic address:
The hippocampus is an important brain structure involved in various psychiatric disorders, and its automatic and accurate segmentation is vital for studying these diseases. Recently, deep learning-based methods have made significant progress in hippocampus segmentation. However, training deep neural network models requires substantial computational resources, time, and a large amount of labeled training data, which is frequently scarce in medical image segmentation.
View Article and Find Full Text PDFNeural Netw
August 2025
Faculty of Electronics, Photonics, and Microsystems, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, Wroclaw, 50-370, Poland.
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View Article and Find Full Text PDFJ Chem Phys
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Department of Physics, Stockholm University, 10691 Stockholm, Sweden.
The water molecule's electronic Cartesian multipole moment and polarizability tensors have been fitted with Gaussian process regression to the internal coordinates and are used to evaluate accurate electrostatic, induction, and dispersion energy components between flexible molecules. The model yields a handful of damping and scaling parameters that were adjusted for the energy components to agree with 2-body symmetry-adapted perturbation theory decomposition and then fine-tuned in order for the total energy to agree with CCSD(T) for small clusters. We present a simple algorithm for rotating symmetric Cartesian tensors and employ a dispersion potential based on multipole polarizabilities.
View Article and Find Full Text PDFNMR Biomed
October 2025
High Field MR Center, Department for Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
Dynamic deuterium (H)-MRSI enables mapping of metabolic fluxes in vivo, but its sensitivity is hampered by the low H gyromagnetic ratio and H-labelled metabolite concentrations. Low-rank denoising can enhance MRSI sensitivity by separating signal from noise. Several methods have been proposed, but the optimal approach for dynamic H-MRSI remains unclear.
View Article and Find Full Text PDFSensors (Basel)
August 2025
The Department of Electrical and Electronic Engineering, School of Engineering, The University of Manchester, Manchester M13 9PL, UK.
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