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1.
Proc Natl Acad Sci U S A ; 120(37): e2218593120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37676911

RESUMO

Despite the variability of music across cultures, some types of human songs share acoustic characteristics. For example, dance songs tend to be loud and rhythmic, and lullabies tend to be quiet and melodious. Human perceptual sensitivity to the behavioral contexts of songs, based on these musical features, suggests that basic properties of music are mutually intelligible, independent of linguistic or cultural content. Whether these effects reflect universal interpretations of vocal music, however, is unclear because prior studies focus almost exclusively on English-speaking participants, a group that is not representative of humans. Here, we report shared intuitions concerning the behavioral contexts of unfamiliar songs produced in unfamiliar languages, in participants living in Internet-connected industrialized societies (n = 5,516 native speakers of 28 languages) or smaller-scale societies with limited access to global media (n = 116 native speakers of three non-English languages). Participants listened to songs randomly selected from a representative sample of human vocal music, originally used in four behavioral contexts, and rated the degree to which they believed the song was used for each context. Listeners in both industrialized and smaller-scale societies inferred the contexts of dance songs, lullabies, and healing songs, but not love songs. Within and across cohorts, inferences were mutually consistent. Further, increased linguistic or geographical proximity between listeners and singers only minimally increased the accuracy of the inferences. These results demonstrate that the behavioral contexts of three common forms of music are mutually intelligible cross-culturally and imply that musical diversity, shaped by cultural evolution, is nonetheless grounded in some universal perceptual phenomena.


Assuntos
Evolução Cultural , Música , Humanos , Idioma , Linguística , Acústica
2.
Proc Natl Acad Sci U S A ; 120(44): e2308828120, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37871204

RESUMO

Here, a molecular-design and carbon dot-confinement coupling strategy through the pyrolysis of bimetallic complex of diethylenetriamine pentaacetic acid under low-temperature is proposed as a universal approach to dual-metal-atom sites in carbon dots (DMASs-CDs). CDs as the "carbon islands" could block the migration of DMASs across "islands" to achieve dynamic stability. More than twenty DMASs-CDs with specific compositions of DMASs (pairwise combinations among Fe, Co, Ni, Mn, Zn, Cu, and Mo) have been synthesized successfully. Thereafter, high intrinsic activity is observed for the probe reaction of urea oxidation on NiMn-CDs. In situ and ex situ spectroscopic characterization and first-principle calculations unveil that the synergistic effect in NiMn-DMASs could stretch the urea molecule and weaken the N-H bond, endowing NiMn-CDs with a low energy barrier for urea dehydrogenation. Moreover, DMASs-CDs for various target electrochemical reactions, including but not limited to urea oxidation, are realized by optimizing the specific DMAS combination in CDs.

3.
Proc Natl Acad Sci U S A ; 119(28): e2122599119, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35787047

RESUMO

We characterize the universal far-from-equilibrium dynamics of the two-dimensional quantum Heisenberg magnet isolated from its environment. For a broad range of initial conditions, we find a long-lived universal prethermal regime characterized by self-similar behavior of spin-spin correlations. We analytically derive the spatial-temporal scaling exponents and find excellent agreement with numerics using phase space methods. The scaling exponents are insensitive to the choice of initial conditions, which include coherent and incoherent spin states with values of total magnetization and energy in a wide range. Compared to previously studied self-similar dynamics in nonequilibrium O(n) field theories and Bose gases, we find qualitatively distinct scaling behavior originating from the presence of spin modes that remain gapless at long times and are protected by the global SU(2) symmetry. Our predictions, which suggest a distinct nonequilibrium universality class from Bose gases and O(n) theories, are readily testable in ultracold atoms simulators of Heisenberg magnets.

4.
Nano Lett ; 24(1): 9-15, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38115185

RESUMO

The universality of physical phenomena is a pivotal concept underlying quantum standards. In this context, the realization of a quantum current standard using silicon single-electron pumps necessitates the verification of the equivalence across multiple devices. Herein, we experimentally investigate the universality of pumped currents from two different silicon single-electron devices which are placed inside the cryogen-free dilution refrigerator whose temperature (mixing chamber plate) was ∼150 mK under the operation of the pump devices. By direct comparison using an ultrastable current amplifier as a galvanometer, we confirm that two pumped currents are consistent with ∼1 ppm uncertainty. Furthermore, we realize quantum-current multiplication with a similar uncertainty by adding the currents of two different gigahertz (GHz)-operated silicon pumps, whose generated currents are confirmed to be identical. These results pave the way for realizing a quantum current standard in the nanoampere range and a quantum metrology triangle experiment using silicon pump devices.

5.
Rep Prog Phys ; 87(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38957892

RESUMO

A test of lepton flavor universality inB±â†’K±µ+µ-andB±â†’K±e+e-decays, as well as a measurement of differential and integrated branching fractions of a nonresonantB±â†’K±µ+µ-decay are presented. The analysis is made possible by a dedicated data set of proton-proton collisions ats=13TeVrecorded in 2018, by the CMS experiment at the LHC, using a special high-rate data stream designed for collecting about 10 billion unbiased b hadron decays. The ratio of the branching fractionsB(B±â†’K±µ+µ-)toB(B±â†’K±e+e-)is determined from the measured double ratioR(K)of these decays to the respective branching fractions of theB±â†’J/ψK±withJ/ψ→µ+µ-ande+e-decays, which allow for significant cancellation of systematic uncertainties. The ratioR(K)is measured in the range1.1

6.
Entropy (Basel) ; 26(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38539771

RESUMO

The Kardar-Parisi-Zhang (KPZ) equation describes a wide range of growth-like phenomena, with applications in physics, chemistry and biology. There are three central questions in the study of KPZ growth: the determination of height probability distributions; the search for ever more precise universal growth exponents; and the apparent absence of a fluctuation-dissipation theorem (FDT) for spatial dimension d>1. Notably, these questions were answered exactly only for 1+1 dimensions. In this work, we propose a new FDT valid for the KPZ problem in d+1 dimensions. This is achieved by rearranging terms and identifying a new correlated noise which we argue to be characterized by a fractal dimension dn. We present relations between the KPZ exponents and two emergent fractal dimensions, namely df, of the rough interface, and dn. Also, we simulate KPZ growth to obtain values for transient versions of the roughness exponent α, the surface fractal dimension df and, through our relations, the noise fractal dimension dn. Our results indicate that KPZ may have at least two fractal dimensions and that, within this proposal, an FDT is restored. Finally, we provide new insights into the old question about the upper critical dimension of the KPZ universality class.

7.
Small ; 19(35): e2301469, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37098645

RESUMO

Single-atom catalysts (SACs) exhibit remarkable potential for electrochemical reduction of CO2 to value-added products. However, the commonly pursued methods for preparing SACs are hard to scale up, and sometimes, lack general applicability because of expensive raw materials and complex synthetic procedures. In addition, the fine tuning of coordination environment of SACs remains challenging due to their structural vulnerability. Herein, a simple and universal strategy is developed to fabricate Ni SACs with different nitrogen coordination numbers through one-step pyrolysis of melamine, Ni(NO3 )∙6H2 O, and polyvinylpyrrolidone at different temperatures. Experimental measurements and theoretical calculations reveal that the low-coordinate Ni SACs exhibit outstanding CO2 reduction performance and stability, achieving a Faradic efficiency (FECO ) of 98.5% at -0.76 V with CO current density of 24.6 mA cm-2 , and maintaining FECO of over 91.0% at all applied potential windows from -0.56 to -1.16 V, benefiting from its coordinatively unsaturated structure to afford high catalytic activity and low barrier for the formation of *COOH intermediate. No significant performance degradation is observed over 50 h of continuous operation. Additionally, several other metallic single-atom catalysts are successfully prepared by this synthetic method, demonstrating the universality of this strategy.

8.
Dev Sci ; : e13379, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899475

RESUMO

The development of reading networks across different languages and cultures provides an important window to address gene-culture interactions in brain functionality development. Previous meta-analyses have explored the neural correlates of reading in different languages with diverse orthographic transparencies. However, it remains unknown whether the neural topographic relationship of different languages varies when taking development into account. To address this issue, we conducted meta-analyses of neuroimaging studies with approaches of activation likelihood estimation and seed-based effect size mapping and focused on two highly contrasting languages, Chinese and English. The meta-analyses covered 61 studies of Chinese reading and 64 studies of English reading by native speakers. The brain reading networks of child and adult readers were further separately analyzed and compared to explore the developmental effects. The results revealed that the commonalities and differences in reading networks for Chinese and English were inconsistent between children and adults. In addition, the reading networks converged with development, and the effects of writing systems on brain function organizations were more salient in the initial stages of reading. An interesting finding was that the left inferior parietal lobule demonstrated increased effect sizes in adults compared with children in both Chinese and English reading, indicating a common developmental feature of reading mechanisms across the two languages. These findings provide new insights into the functional evolution and cultural modulation of brain reading networks. RESEARCH HIGHLIGHTS: Meta-analyses with approaches of activation likelihood estimation and seed-based effect size mapping were performed to evaluate the developmental characteristics of brain reading networks. The engagement of universal and language-specific reading networks was different between children and adults, and the reading networks converged with increased reading experience. Overall the middle/inferior occipital and inferior/middle frontal gyrus were specific to Chinese and the middle temporal, right inferior frontal gyrus were specific to English. The left inferior parietal lobule was engaged more in adults than children in Chinese and English reading, demonstrating a common developmental feature of reading mechanisms.

9.
Philos Trans A Math Phys Eng Sci ; 381(2252): 20220276, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37334458

RESUMO

The backbone of non-equilibrium thermodynamics is the stability structure, where entropy is related to a Lyapunov function of thermodynamic equilibrium. Stability is the background of natural selection: unstable systems are temporary, and stable ones survive. The physical concepts from the stability structure and the related formalism of constrained entropy inequality are universal by construction. Therefore, the mathematical tools and the physical concepts of thermodynamics help formulate dynamical theories of any systems in social and natural sciences. This article is part of the theme issue 'Thermodynamics 2.0: Bridging the natural and social sciences (Part 1)'.

10.
Mem Cognit ; 51(3): 505-508, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36859524

RESUMO

In this editorial, the editors briefly introduce the aims of the Special Issue. If the goal of the scientific field of Cognitive Psychology is to improve our understanding of human cognition, then research needs to be conducted on a much broader slice of humanity than it has mostly been doing. The first aim of this Special Issue was to examine cognitive processes in populations that are different from the typical Western young adult samples often used in previously published studies. Studies in this issue therefore included both non-WEIRD participants as well as WEIRD participants who process information using different sensory experiences (e.g., individuals who are deaf). The second aim was to amplify - where possible - the research of scholars from less well-represented regions. The authors of the studies were affiliated with a diverse range of academic institutes and frequently included partnerships between Western and non-Western investigators.


Assuntos
Cognição , Adulto Jovem , Humanos
11.
Proc Natl Acad Sci U S A ; 117(1): 171-176, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31852827

RESUMO

Fine-grained sediment (grain size under 2,000 µm) builds floodplains and deltas, and shapes the coastlines where much of humanity lives. However, a universal, physically based predictor of sediment flux for fine-grained rivers remains to be developed. Herein, a comprehensive sediment load database for fine-grained channels, ranging from small experimental flumes to megarivers, is used to find a predictive algorithm. Two distinct transport regimes emerge, separated by a discontinuous transition for median bed grain size within the very fine sand range (81 to 154 µm), whereby sediment flux decreases by up to 100-fold for coarser sand-bedded rivers compared to river with silt and very fine sand beds. Evidence suggests that the discontinuous change in sediment load originates from a transition of transport mode between mixed suspended bed load transport and suspension-dominated transport. Events that alter bed sediment size near the transition may significantly affect fluviocoastal morphology by drastically changing sediment flux, as shown by data from the Yellow River, China, which, over time, transitioned back and forth 3 times between states of high and low transport efficiency in response to anthropic activities.

12.
Entropy (Basel) ; 25(12)2023 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-38136467

RESUMO

Persistent homology is a natural tool for probing the topological characteristics of weighted graphs, essentially focusing on their 0-dimensional homology. While this area has been thoroughly studied, we present a new approach to constructing a filtration for cluster analysis via persistent homology. The key advantages of the new filtration is that (a) it provides richer signatures for connected components by introducing non-trivial birth times, and (b) it is robust to outliers. The key idea is that nodes are ignored until they belong to sufficiently large clusters. We demonstrate the computational efficiency of our filtration, its practical effectiveness, and explore into its properties when applied to random graphs.

13.
Entropy (Basel) ; 25(9)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37761623

RESUMO

Over the past three decades, describing the reality surrounding us using the language of complex networks has become very useful and therefore popular. One of the most important features, especially of real networks, is their complexity, which often manifests itself in a fractal or even multifractal structure. As a generalization of fractal analysis, the multifractal analysis of complex networks is a useful tool for identifying and quantitatively describing the spatial hierarchy of both theoretical and numerical fractal patterns. Nowadays, there are many methods of multifractal analysis. However, all these methods take into account only the fact of connection between nodes (and eventually the weight of edges) and do not take into account the real positions (coordinates) of nodes in space. However, intuition suggests that the geometry of network nodes' position should have a significant impact on the true fractal structure. Many networks identified in nature (e.g., air connection networks, energy networks, social networks, mountain ridge networks, networks of neurones in the brain, and street networks) have their own often unique and characteristic geometry, which is not taken into account in the identification process of multifractality in commonly used methods. In this paper, we propose a multifractal network analysis method that takes into account both connections between nodes and the location coordinates of nodes (network geometry). We show the results for different geometrical variants of the same network and reveal that this method, contrary to the commonly used method, is sensitive to changes in network geometry. We also carry out tests for synthetic as well as real-world networks.

14.
Entropy (Basel) ; 25(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36832551

RESUMO

A discrete version of opinion dynamics systems, based on the Biswas-Chatterjee-Sen (BChS) model, has been studied on Barabási-Albert networks (BANs). In this model, depending on a pre-defined noise parameter, the mutual affinities can assign either positive or negative values. By employing extensive computer simulations with Monte Carlo algorithms, allied with finite-size scaling hypothesis, second-order phase transitions have been observed. The corresponding critical noise and the usual ratios of the critical exponents have been computed, in the thermodynamic limit, as a function of the average connectivity. The effective dimension of the system, defined through a hyper-scaling relation, is close to one, and it turns out to be connectivity-independent. The results also indicate that the discrete BChS model has a similar behavior on directed Barabási-Albert networks (DBANs), as well as on Erdös-Rènyi random graphs (ERRGs) and directed ERRGs random graphs (DERRGs). However, unlike the model on ERRGs and DERRGs, which has the same critical behavior for the average connectivity going to infinity, the model on BANs is in a different universality class to its DBANs counterpart in the whole range of the studied connectivities.

15.
Philos Trans A Math Phys Eng Sci ; 380(2219): 20210090, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35094560

RESUMO

The one-dimensional Galerkin-truncated Burgers equation, with both dissipation and noise terms included, is studied using spectral methods. When the truncation-scale Reynolds number [Formula: see text] is varied, from very small values to order 1 values, the scale-dependent correlation time [Formula: see text] is shown to follow the expected crossover from the short-distance [Formula: see text] Edwards-Wilkinson scaling to the universal long-distance Kardar-Parisi-Zhang scaling [Formula: see text]. In the inviscid limit, [Formula: see text], we show that the system displays another crossover to the Galerkin-truncated inviscid-Burgers regime that admits thermalized solutions with [Formula: see text]. The scaling forms of the time-correlation functions are shown to follow the known analytical laws and the skewness and excess kurtosis of the interface increments distributions are characterized. This article is part of the theme issue 'Scaling the turbulence edifice (part 2)'.

16.
Philos Trans A Math Phys Eng Sci ; 380(2218): 20210089, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35034491

RESUMO

Inspection of available data on the decay exponent for the kinetic energy of homogeneous and isotropic turbulence (HIT) shows that it varies by as much as 100%. Measurements and simulations often show no correspondence with theoretical arguments, which are themselves varied. This situation is unsatisfactory given that HIT is a building block of turbulence theory and modelling. We take recourse to a large base of direct numerical simulations and study decaying HIT for a variety of initial conditions. We show that the Kolmogorov decay exponent and the Birkhoff-Saffman decay are both observed, albeit approximately, for long periods of time if the initial conditions are appropriately arranged. We also present, for both cases, other turbulent statistics such as the velocity derivative skewness, energy spectra and dissipation, and show that the decay and growth laws are approximately as expected theoretically, though the wavenumber spectrum near the origin begins to change relatively quickly, suggesting that the invariants do not strictly exist. We comment briefly on why the decay exponent has varied so widely in past experiments and simulations. This article is part of the theme issue 'Scaling the turbulence edifice (part 1)'.

17.
Proc Natl Acad Sci U S A ; 116(28): 13780-13784, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31209045

RESUMO

The pinch-off of a bubble is an example of the formation of a singularity, exhibiting a characteristic separation of length and time scales. Because of this scale separation, one expects universal dynamics that collapse into self-similar behavior determined by the relative importance of viscous, inertial, and capillary forces. Surprisingly, however, the pinch-off of a bubble in a large tank of viscous liquid is known to be nonuniversal. Here, we show that the pinch-off dynamics of a bubble confined in a capillary tube undergo a sequence of two distinct self-similar regimes, even though the entire evolution is controlled by a balance between viscous and capillary forces. We demonstrate that the early-time self-similar regime restores universality to bubble pinch-off by erasing the system's memory of the initial conditions. Our findings have important implications for bubble/drop generation in microfluidic devices, with applications in inkjet printing, medical imaging, and synthesis of particulate materials.

18.
Molecules ; 27(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35956996

RESUMO

In this study, we developed a simple strategy to prepare a biofilm reactor (BFR) sensor for the universal biochemical oxygen demand (BOD) determination. The microorganisms in fresh water were domesticated by artificial seawater with different salinity gradients successively to prepare the BFR sensor. The prepared BFR sensor exhibits an efficient ability to degrade a variety of organic substances. The linear range of BOD determination by the BFR sensor is 1.0-10.0 mg/L-1 with a correlation coefficient of 0.9951. The detection limit is 0.30 mg/L according to three times of signal-to-noise ratio. What is more, the BFR sensor displayed excellent performances for the BOD determination of different water samples, including both fresh water and seawater. The 16S-rRNA gene sequencing technology was used to analyze the microbial species before and after the domestication. The results show that it is a general approach for the rapid BOD determination in different water samples.


Assuntos
Técnicas Biossensoriais , Água , Biofilmes , Técnicas Biossensoriais/métodos , Oxigênio/química , Água do Mar , Águas Residuárias/química , Água/química
19.
Entropy (Basel) ; 24(10)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37420370

RESUMO

The stochastic transport of particles in a disordered two-dimensional layered medium, driven by correlated y-dependent random velocity fields is usually referred to as random shear model. This model exhibits a superdiffusive behavior in the x direction ascribable to the statistical properties of the disorder advection field. By introducing layered random amplitude with a power-law discrete spectrum, the analytical expressions for the space and time velocity correlation functions, together with those of the position moments, are derived by means of two distinct averaging procedures. In the case of quenched disorder, the average is performed over an ensemble of uniformly spaced initial conditions: albeit the strong sample-to-sample fluctuations, and universality appears in the time scaling of the even moments. Such universality is exhibited in the scaling of the moments averaged over the disorder configurations. The non-universal scaling form of the no-disorder symmetric or asymmetric advection fields is also derived.

20.
Entropy (Basel) ; 24(6)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35741554

RESUMO

Spiking neural P systems (SN P systems for short) realize the high abstraction and simulation of the working mechanism of the human brain, and adopts spikes for information encoding and processing, which are regarded as one of the third-generation neural network models. In the nervous system, the conduction of excitation depends on the presence of membrane potential (also known as the transmembrane potential difference), and the conduction of excitation on neurons is the conduction of action potentials. On the basis of the SN P systems with polarizations, in which the neuron-associated polarization is the trigger condition of the rule, the concept of neuronal membrane potential is introduced into systems. The obtained variant of the SN P system features charge accumulation and computation within neurons in quantity, as well as transmission between neurons. In addition, there are inhibitory synapses between neurons that inhibit excitatory transmission, and as such, synapses cause postsynaptic neurons to generate inhibitory postsynaptic potentials. Therefore, to make the model better fit the biological facts, inhibitory rules and anti-spikes are also adopted to obtain the spiking neural P systems with membrane potentials, inhibitory rules, and anti-spikes (referred to as the MPAIRSN P systems). The Turing universality of the MPAIRSN P systems as number generating and accepting devices is demonstrated. On the basis of the above working mechanism of the system, a small universal MPAIRSN P system with 95 neurons for computing functions is designed. The comparisons with other SN P models conclude that fewer neurons are required by the MPAIRSN P systems to realize universality.

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