New passive- and active-source seismic experiments reveal unusually high mantle P-wave speeds that extend beneath the remnants of the world's largest known large igneous province, making up the 120-million-year-old Ontong-Java-Manihiki-Hikurangi Plateau. Sub-Moho P phases of ~8.8 ± 0.2 km/s are resolved with negligible azimuthal seismic anisotropy, but with strong radial anisotropy (~10%), characteristic of aggregates of olivine with an AG crystallographic fabric. These seismic results are the first in situ evidence for this fabric in the upper mantle. We show that its presence can be explained by isotropic horizontal dilation and vertical flattening due to late-stage gravitational collapse and spreading in the top 10 to 20 km of a depleted, mushroom-shaped, superplume head on a horizontal length scale of 1000 km or more. This way, it provides a seismic tool to track plumes long after the thermal effects have ceased.
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http://dx.doi.org/10.1126/sciadv.aba7118 | DOI Listing |
Nature
January 2025
Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands.
Seismic tomographic models based only on wave velocities have limited ability to distinguish between a thermal or compositional origin for Earth's 3D structure. Complementing wave velocities with attenuation observations can make that distinction, which is fundamental for understanding mantle convection evolution. However, global 3D attenuation models are only available for the upper mantle at present.
View Article and Find Full Text PDFCureus
December 2024
Biomedical Sciences, University of Chicago, Chicago, USA.
Pediatric-type follicular lymphoma (PTFL) is an extremely rare B-cell lymphoma that primarily affects children and young adults, typically in individuals under 25 years old, with a median age of 15 years. Here, we report a rare case of PTFL in a 27-year-old adult male who presented with a slow-growing mass near his left ear. Initial CT scans of the neck revealed two oval-shaped, smooth, well-defined, homogeneously enhancing soft tissue density lesions in the superficial lobe of the left parotid gland.
View Article and Find Full Text PDFLeuk Lymphoma
January 2025
Department of Lymphoma and Myeloma, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Cell Commun Signal
January 2025
Laboratory of Metabolism and Cancer Prevention, Department of Cell Biology & Molecular Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA.
FGF21 regulates local and systemic metabolic homeostasis. High serum FGF21 was found in obesity, metabolic syndrome, type 2 diabetes mellitus, and coronary heart disease. The pathways linking obesity and breast cancer remain elusive.
View Article and Find Full Text PDFBull Environ Contam Toxicol
January 2025
School of Mathematics and Physics, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu, 215123, China.
This study focuses on the composition and sources of dissolved organic matter (DOM) in the Fancun Reservoir, located in Ningguo City, Anhui Province, China. The investigation was conducted by analyzing the spectral characteristics of DOM using UV-Vis absorption spectra and fluorescence spectroscopy. The humic substances were dominated by fulvic acid, with an average DOM concentration of 30.
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