The Hoyle state plays a crucial role in the helium burning of stars heavier than our Sun and in the production of carbon and other elements necessary for life. This excited state of the carbon-12 nucleus was postulated by Hoyle as a necessary ingredient for the fusion of three alpha particles to produce carbon at stellar temperatures. Although the Hoyle state was seen experimentally more than a half century ago nuclear theorists have not yet uncovered the nature of this state from first principles. In this Letter we report the first ab initio calculation of the low-lying states of carbon-12 using supercomputer lattice simulations and a theoretical framework known as effective field theory. In addition to the ground state and excited spin-2 state, we find a resonance at -85(3) MeV with all of the properties of the Hoyle state and in agreement with the experimentally observed energy.
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http://dx.doi.org/10.1103/PhysRevLett.106.192501 | DOI Listing |
PLoS One
January 2025
Department of Psychology and Neuroscience, Duke University, Durham, North Carolina, United States of America.
Socioeconomic status (SES) is associated with well-being outcomes across studies; however, there is wide variation in its measurement, particularly in adolescence. One key difference in measures of SES concerns whether participants relay objective information-for example, years of education, household income-or subjective perceptions of socioeconomic status, either with or without reference to others or society. Although parents are often considered the best source of SES information-especially objective SES-within families, interviewing parents within the context of adolescent research is costly, time-consuming, and not always feasible.
View Article and Find Full Text PDFChemosphere
February 2025
Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, Louisville, KY 40202, USA; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40202, USA. Electronic address:
Lung cancer is an important human health concern because of its high mortality rate, with many cases caused by environmental chemicals other than tobacco. Particulate hexavalent chromium [Cr(VI)] is a well-established human lung carcinogen, but how Cr(VI) induces lung cancer is poorly understood. Chromosome instability, a hallmark of lung cancer, is considered a major driving factor in Cr(VI)-induced lung cancer.
View Article and Find Full Text PDFAffect Sci
December 2024
Department of Psychological Science, University of California, Irvine, Irvine, CA USA.
Unlabelled: Concerns regarding the potential negative impacts of digital technology use on youth mental health and well-being are high. However, most studies have several methodological limitations: relying on cross-sectional designs and retrospective reports, assessing technology use as an omnibus construct, and focusing on between- instead of within-person comparisons. This study addresses these limitations by prospectively following young adolescents ( = 388) over a 14-day ecological momentary assessment study to test whether adolescents' digital technology use is linked with self-reported emotional dysregulation and self-esteem and whether these relationships are stronger for adolescent girls than boys.
View Article and Find Full Text PDFSeismic imaging is one of the most powerful tools available for constraining the internal structure and composition of planetary bodies as well as enabling our understanding planetary evolution, geology, and distribution of natural resources. However, traditional seismic instrumentation can be heavy and voluminous, expensive, and/or difficult to rapidly deploy in large numbers. Distributed acoustic sensing (DAS) provides a promising new alternative given the ease of deployment, light weight and simplicity of fiber optic cables.
View Article and Find Full Text PDFSubst Use Misuse
January 2025
Department of Psychology and Neuroscience, Duke University, Durham, NC, USA.
Objective: Understanding factors associated with early onset of substance use is critical as using alcohol or drugs at a young age is a strong predictor of later substance dependency. Experiencing stressful life events is associated with increased risk for early substance use in youth. Hair cortisol concentration (HCC) is considered a biomarker of psychological stress experienced over longer periods of time.
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