688 results match your criteria: "International Centre for Theoretical Physics[Affiliation]"
PLoS Comput Biol
January 2024
Institute for Advanced Study, University of Amsterdam, Amsterdam, The Netherlands.
Plant and pollinator communities are vital for transnational food chains. Like many natural systems, they are affected by global change: rapidly deteriorating conditions threaten their numbers. Previous theoretical studies identified the potential for community-wide collapse above critical levels of environmental stressors-so-called bifurcation-induced tipping points.
View Article and Find Full Text PDFPhys Rev Lett
December 2023
Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany.
The fission of a string connecting two charges is an astounding phenomenon in confining gauge theories. The dynamics of this process have been studied intensively in recent years, with plenty of numerical results yielding a dichotomy: the confining string can decay relatively fast or persist up to extremely long times. Here, we put forward a dynamical localization transition as the mechanism underlying this dichotomy.
View Article and Find Full Text PDFNat Commun
December 2023
Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China.
Over the satellite era, Antarctic sea ice exhibited an overall long-term increasing trend, contrary to the Arctic reduction under global warming. However, the drastic decline of Antarctic sea ice in 2014-2018 raises questions about its interannual and decadal-scale variabilities, which are poorly understood and predicted. Here, we identify an Antarctic sea ice decadal oscillation, exhibiting a quasi-period of 8-16 years, that is anticorrelated with the Pacific Quasi-Decadal Oscillation (r = -0.
View Article and Find Full Text PDFPLoS Comput Biol
December 2023
Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong.
The Michaelis-Menten (MM) rate law has been the dominant paradigm of modeling biochemical rate processes for over a century with applications in biochemistry, biophysics, cell biology, systems biology, and chemical engineering. The MM rate law and its remedied form stand on the assumption that the concentration of the complex of interacting molecules, at each moment, approaches an equilibrium (quasi-steady state) much faster than the molecular concentrations change. Yet, this assumption is not always justified.
View Article and Find Full Text PDFEvolution
March 2024
Departamento de Física Universidade Federal do Paraná, Curitiba, Brazil.
Geographic barriers can come and go depending on natural conditions. These fluctuations cause population cycles of expansion and contraction, introducing intermittent migrations that may not hinder speciation but rather promote diversification. Here, we study a neutral 2-island speciation model with intermittent migration driven by sea-level fluctuations.
View Article and Find Full Text PDFJ Med Imaging Radiat Sci
March 2024
Department of Allied Health Professions, Azienda Ospedaliero-Universitaria Careggi, 50134 Florence, Italy.
Introduction: Both cone-beam computed tomography (CBCT) and surface-guided radiotherapy (SGRT) are used for breast patient positioning verification before treatment delivery. SGRT may reduce treatment time and imaging dose by potentially reduce the number of CBCT needed. The aim of this study was to compare the displacements resulting in positioning from the Image Guided Radiation Therapy (IGRT) 3D and SGRT methods and to design a clinical workflow for SGRT implementation in breast radiotherapy to establish an imaging strategy based on the data obtained.
View Article and Find Full Text PDFSensors (Basel)
November 2023
The Abdus Salam International Centre for Theoretical Physics, 34151 Trieste, Italy.
The escalating global water usage and the increasing strain on major cities due to water shortages highlights the critical need for efficient water management practices. In water-stressed regions worldwide, significant water wastage is primarily attributed to leakages, inefficient use, and aging infrastructure. Undetected water leakages in buildings' pipelines contribute to the water waste problem.
View Article and Find Full Text PDFMicroorganisms
November 2023
The Abdus Salam International Centre for Theoretical Physics (ICTP), 34151 Trieste, Italy.
A comprehensive overview of the recent physics-inspired genome analysis tool, GenomeBits, is presented. This is based on traditional signal processing methods such as discrete Fourier transform (DFT). GenomeBits can be used to extract underlying genomics features from the distribution of nucleotides, and can be further used to analyze the mutation patterns in viral genomes.
View Article and Find Full Text PDFPhys Rev Lett
November 2023
Institute for Theoretical Physics, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
We show that the Kontsevich-Segal (KS) criterion, applied to the complex saddles that specify the semiclassical no-boundary wave function, acts as a selection mechanism on inflationary scalar field potentials. Completing the observable phase of slow-roll inflation with a no-boundary origin, the KS criterion effectively bounds the tensor-to-scalar ratio of cosmic microwave background fluctuations to be less than 0.08, in line with current observations.
View Article and Find Full Text PDFPhys Rev E
October 2023
Science, Mathematics and Technology Cluster, Singapore University of Technology and Design, 8 Somapah Road, 487372 Singapore.
We study the Hamiltonian dynamics of a many-body quantum system subjected to periodic projective measurements, which leads to probabilistic cellular automata dynamics. Given a sequence of measured values, we characterize their dynamics by performing a principal component analysis (PCA). The number of principal components required for an almost complete description of the system, which is a measure of complexity we refer to as PCA complexity, is studied as a function of the Hamiltonian parameters and measurement intervals.
View Article and Find Full Text PDFNat Commun
November 2023
Condensed Matter and Statistical Physics, The Abdus Salam International Centre for Theoretical Physics, Trieste, Italy.
Challenging the basis of our chemical intuition, recent experimental evidence reveals the presence of a new type of intrinsic fluorescence in biomolecules that exists even in the absence of aromatic or electronically conjugated chemical compounds. The origin of this phenomenon has remained elusive so far. In the present study, we identify a mechanism underlying this new type of fluorescence in different biological aggregates.
View Article and Find Full Text PDFFundam Res
September 2024
CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China.
The space-based laser interferometers, LISA, Taiji and TianQin, are targeting to observe milliHz gravitational waves (GWs) in the 2030s. The joint observations from multiple space-based detectors yield significant advantages. In this work, we recap the studies and investigations for the joint space-based GW detector networks to highlight: 1) the high precision of sky localization for the massive binary black hole (BBH) coalescences and the GW sirens in the cosmological implication, 2) the effectiveness to test the parity violation in the stochastic GW background observations, 3) the efficiency of subtracting galactic foreground, 4) the improvement in stellar-mass BBH observations.
View Article and Find Full Text PDFSci Rep
November 2023
Paul-Drude-Institut für Festkörperelektronik (PDI), Leibniz-Institut im Forschungsverbund Berlin e.V., Hausvogteiplatz 5-7, 10117, Berlin, Germany.
J Phys Chem B
November 2023
International Centre for Theoretical Physics, Strada Costiera 11, 34151 Trieste, Italy.
The structure of the excess proton in liquid water has been the subject of lively debate on both experimental and theoretical fronts for the last century. Fluctuations of the proton are typically interpreted in terms of limiting states referred to as the Eigen and Zundel species. Here, we put these ideas under the microscope, taking advantage of recent advances in unsupervised learning that use local atomic descriptors to characterize environments of acidic water combined with advanced clustering techniques.
View Article and Find Full Text PDFPhys Rev Lett
October 2023
SISSA and INFN Sezione di Trieste, via Bonomea 265, 34136 Trieste, Italy.
Quantum impurity models (QIMs) are ubiquitous throughout physics. As simplified toy models they provide crucial insights for understanding more complicated strongly correlated systems, while in their own right are accurate descriptions of many experimental platforms. In equilibrium, their physics is well understood and have proven a testing ground for many powerful theoretical tools, both numerical and analytical, in use today.
View Article and Find Full Text PDFSci Rep
October 2023
Paul-Drude-Institut für Festkörperelektronik (PDI), Leibniz-Institut im Forschungsverbund Berlin e.V., Hausvogteiplatz 5-7, 10117, Berlin, Germany.
Quantum mechanics increasingly penetrates modern technologies but, due to its non-deterministic nature seemingly contradicting our classical everyday world, our comprehension often stays elusive. Arguing along the correspondence principle, classical mechanics is often seen as a theory for large systems where quantum coherence is completely averaged out. Surprisingly, it is still possible to reconstruct the coherent dynamics of a quantum bit (qubit) by using a classical model system.
View Article and Find Full Text PDFPhys Rev Lett
October 2023
SISSA and INFN Sezione di Trieste, via Bonomea 265, 34136 Trieste, Italy.
Owing to its probabilistic nature, a measurement process in quantum mechanics produces a distribution of possible outcomes. This distribution-or its Fourier transform known as full counting statistics (FCS)-contains much more information than say the mean value of the measured observable, and accessing it is sometimes the only way to obtain relevant information about the system. In fact, the FCS is the limit of an even more general family of observables-the charged moments-that characterize how quantum entanglement is split in different symmetry sectors in the presence of a global symmetry.
View Article and Find Full Text PDFPhys Rev E
September 2023
Quantitative Life Sciences, The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste 34151, Italy.
The assumption of constant population size is central in population genetics. It led to a large body of results that is robust to modeling choices and that has proven successful to understand evolutionary dynamics. In reality, allele frequencies and population size are both determined by the interaction between a population and the environment.
View Article and Find Full Text PDFSci Rep
October 2023
Fachbereich Physik, Universität Konstanz, 78464, Konstanz, Germany.
Collective self-organization of animal groups is a recurring phenomenon in nature which has attracted a lot of attention in natural and social sciences. To understand how collective motion can be achieved without the presence of an external control, social interactions have been considered which regulate the motion and orientation of neighbors relative to each other. Here, we want to understand the motivation and possible reasons behind the emergence of such interaction rules using an experimental model system of light-responsive active colloidal particles (APs).
View Article and Find Full Text PDFIn the past decade, there has been a growth in using Zirconium-89 (Zr) as a radionuclide in nuclear medicine for cancer diagnostic imaging and drug discovery processes. Although one of the most popular chelators for Zr, desferrioxamine (DFO) is typically presented as a hexadentate ligand, our work suggests a different scenario. The coordination structure of the Zr-DFO complex has primarily been informed by DFT-based calculations, which typically ignore temperature and therefore entropic and dynamic solvent effects.
View Article and Find Full Text PDFThe horizontal transfer of genes is fundamental for the eco-evolutionary dynamics of microbial communities, such as oceanic plankton, soil, and the human microbiome. In the case of an acquired beneficial gene, classic population genetics would predict a genome-wide selective sweep, whereby the genome spreads clonally within the community and together with the beneficial gene, removing genome diversity. Instead, several sources of metagenomic data show the existence of "gene-specific sweeps", whereby a beneficial gene spreads across a bacterial community, maintaining genome diversity.
View Article and Find Full Text PDFHeliyon
October 2023
MLAB, STI Unit, The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy.
A thermal lensing approach based on parabolic approximation and Mach-Zehnder interferometer for measuring optical absorption and thermal diffusivity coefficients in pure solvents is described in this work. The approach combines the sensitivity of both thermal lensing methods and interferometry techniques. The photothermal effect is induced by a pump laser beam generating localized changes in the refractive index of the sample, which are observed as a shift in phase of the interference pattern.
View Article and Find Full Text PDFSci Total Environ
January 2024
Departamento de Ingeniería, Aqualogs SAS, 11011 Bogotá, Colombia.
This study examines the spatiotemporal variations of PM, PM, SO, O, NO, and NO concentrations in Northwestern South America (NWSA). We assess the efficacy of existing policies, identify underlying phenomena, and highlight areas for further research. Significant findings have emerged by analyzing reanalysis and in-situ data, employing the WRF-Chem model, and utilizing a new Lagrangian framework designed to overcome some drawbacks common to analysis of pollution Long-Range Transport.
View Article and Find Full Text PDFMaterials (Basel)
September 2023
Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Torun, Grudziadzka 5, 87-100 Torun, Poland.
Measurement of thermal properties of thin films is challenging. In particular, thermal characterization is very difficult in semi-transparent samples. Here, we use two photothermal methods to obtain information about the thermal diffusivity as well as thermal conductivity of azoheteroarene functionalized polymer thin layers.
View Article and Find Full Text PDFSci Rep
September 2023
Chair of Econophysics and Complex Systems, Ecole Polytechnique, 91128, Palaiseau Cedex, France.
We use an agnostic information-theoretic approach to investigate the statistical properties of natural images. We introduce the Multiscale Relevance (MSR) measure to assess the robustness of images to compression at all scales. Starting in a controlled environment, we characterize the MSR of synthetic random textures as function of image roughness [Formula: see text] and other relevant parameters.
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