Power law distributions have been observed in numerous physical and social systems; for example, the size distributions of particles, aerosols, corporations, and cities are often power laws. Each system is an ensemble of clusters, comprising units that combine with or dissociate from the cluster. Constructing models and investigating their properties are needed to understand how such clusters evolve. To describe the growth of clusters, we hypothesize that a distribution obeys a governing population dynamics equation based on a reversible association-dissociation process. The rate coefficients are considered to depend on the cluster size as power expressions, thus providing an explanation for the asymptotic evolution of power law distributions.
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http://dx.doi.org/10.1103/PhysRevE.72.037104 | DOI Listing |
Genet Epidemiol
January 2025
Interdisciplinary Program of Bioinformatics, College of Natural Science, Seoul National University, Seoul, South Korea.
In this article, we proposed a new method named fused mixed graphical model (FMGM), which can infer network structures associated with dichotomous phenotypes. FMGM is based on a pairwise Markov random field model, and statistical analyses including the proposed method were conducted to find biological markers and underlying network structures of the atopic dermatitis (AD) from multiomics data of 6-month-old infants. The performance of FMGM was evaluated with simulations by using synthetic datasets of power-law networks, showing that FMGM had superior performance for identifying the differences of the networks compared to the separate inference with the previous method, causalMGM (F1-scores 0.
View Article and Find Full Text PDFSci Rep
January 2025
School of City and Architecture Engineering, Zaozhuang University, Zaozhuang, 277160, Shandong, China.
To study the enhancement effect of carbon nanotubes (CNTs) on the splitting tensile properties of foamed concrete backfill in which cement and fly ash were used as the cementitious materials and natural sand was used as the aggregate, specimens of CNT-modified foamed concrete backfill were prepared. Brazilian splitting tests were used to investigate the splitting tensile strength of the CNT-modified foamed concrete backfill, and the digital speckle correlation method was used to analyze the stress field characteristics and crack expansion law of the specimens during splitting tensile testing. The stress-strain characteristics and energy dissipation laws of the backfill were studied at various static loading rates, and a relationship between the splitting tensile strength, ultimate strain, and loading rate was established.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
China Three Gorges Corporation, Beijing 100038, China.
With the rapid decline in the levelized cost, offshore wind power offers a new option for the clean energy transition of the power sector in China's coastal areas. Here, we develop a power system capacity expansion and operation optimization model to simulate the penetration of offshore wind power in China and quantify the associated health effects. We find that offshore wind power has great potential in mitigating the negative impacts of existing coal-fired power emissions.
View Article and Find Full Text PDFInternet Interv
March 2025
Department of Public Health, University Of Copenhagen, Øster Farimagsgade 5, 1353 København K, Denmark.
Parental relationship dissolution is among the most prevalent life crises for youths and is associated with both short- and long-term intra- and interpersonal struggles. Extant support programs tend to be in-person and in a group format. However, the structure and personnel needed for these programs make them costly to implement, less accessible, and difficult to scale.
View Article and Find Full Text PDFCan Med Educ J
December 2024
Temerty Faculty of Medicine, University of Toronto, Ontario, Canada.
Background: Equity-deserving groups are communities marginalized from institutional power by oppressive forces (e.g., racism, sexism, homophobia, ableism).
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