It is argued that within the standard Big Bang cosmological model the bulk of the mass of the luminous parts of the large galaxies likely had been assembled by redshift z approximately 10. Galaxy assembly this early would be difficult to fit in the widely discussed adiabatic cold dark matter model for structure formation, but it could agree with an isocurvature version in which the cold dark matter is the remnant of a massive scalar field frozen (or squeezed) from quantum fluctuations during inflation. The squeezed field fluctuations would be Gaussian with zero mean, and the distribution of the field mass therefore would be the square of a random Gaussian process. This offers a possibly interesting new direction for the numerical exploration of models for cosmic structure formation.
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http://dx.doi.org/10.1073/pnas.95.1.67 | DOI Listing |
Plant Dis
January 2025
University of Florida Tropical Research and Education Center, Plant Pathology, 1615 SE 23rd Way, Homestead, Florida, United States, 33031-3314;
The commercial production of passion fruit is geographically limited (California, Florida, and Hawaii), but the development of cold-tolerant varieties could expand it beyond warm-climate states (Stafne et.al. 2023).
View Article and Find Full Text PDFAstrophys J Lett
January 2025
Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101, USA;
The GD-1 stellar stream exhibits spur and gap structures that may result from a close encounter with a dense substructure. When interpreted as a dark matter subhalo, the perturber is denser than predicted in the standard cold dark matter (CDM) model. In self-interacting dark matter (SIDM), however, a halo could evolve into a phase of gravothermal collapse, resulting in a higher central density than its CDM counterpart.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
School of Mathematics and Statistics, University of Sheffield, Hounsfield Road, Sheffield S3 7RH, United Kingdom.
Plant Dis
December 2024
The Ohio State University, Plant Pathology, 2021 Coffey Road, Columbus, Ohio, United States, 43210;
, commonly known as stock, is a flowering plant species in the Brassicaceae popularly used as a cut flower due to its fragrant, long-lasting blooms. In September 2023, stock 'Iron White' plants displaying symptoms and signs of downy mildew were observed within a high tunnel in a cut flower farm in Franklin Co., OH.
View Article and Find Full Text PDFPlant Physiol
December 2024
Plant Breeding, TUM School of Life Sciences, Technical University of Munich, Freising 85354, Germany.
The sustainability of maize cultivation would benefit tremendously from early sowing, but is hampered by low temperatures during early development in temperate climates. We show that allelic variation within the gene encoding subunit M of the NADH-dehydrogenase-like (NDH) complex (ndhm1) in a European maize landrace affects several quantitative traits that are relevant during early development in cold climates through NDH-mediated cyclic electron transport around photosystem I, a process crucial for photosynthesis and photoprotection. Beginning with a genome-wide association study for maximum potential quantum yield of photosystem II in dark-adapted leaves (Fv/Fm), we capitalized on the large phenotypic effects of a hAT transposon insertion in ndhm1 on multiple quantitative traits (early plant height [EPH], Fv/Fm, chlorophyll content, and cold tolerance) caused by the reduced protein levels of NDHM and associated NDH components.
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