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Drainage divide migration alters the geometry of drainage basins, influencing the distribution of water, erosion, sediments, and ecosystems across Earth's surface. The rate of divide migration is governed by differences in erosion rates across the divide and is thus sensitive to spatiotemporal variations in tectonics and climate. However, established approaches for quantifying divide migration rates offer only indirect evidence for the motion of the divide and provide only migration rate averages. Consequently, transience in divide migration cannot be resolved, hindering the ability to explore environmental changes that drive the dynamics of such potential transience. Here, we study a set of datable terraces identified as markers of paleo-divide locations, which provide direct evidence for the paleo motion of the divide. The location and age of the terraces reveal intermittent divide migration at timescales of 10 to 10 y, with phases of rapid migration-at rates more than twice the average-which coincide with documented regional paleoclimate fluctuations. These findings highlight the intermittent nature of divide migration dynamics over geomorphic timescales and its potential sensitivity to climate changes, underscoring the impact of such changes on the planform evolution of drainage basins.
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http://dx.doi.org/10.1073/pnas.2408426122 | DOI Listing |
Neurobiol Dis
September 2025
Department of Neuroscience, Developmental and Regenerative Biology, The University of Texas at San Antonio, San Antonio, TX, USA; Brain Health Consortium, The University of Texas at San Antonio, San Antonio, TX, USA. Electronic address:
Temporal lobe epilepsy is associated with aberrant neurogenesis and ectopic migration of adult-born granule cells (abGCs), yet the molecular mechanisms driving these changes remain poorly defined. Using a pilocarpine-induced mouse model of temporal lobe epilepsy and chemogenetic silencing of abGCs via Designer Receptors Exclusively Activated by Designer Drugs (DREADDs), we previously demonstrated that abGC inhibition reduces both ectopic migration and seizure susceptibility. To identify underlying molecular regulators, we performed RNA sequencing of FACS-isolated abGCs and identified Rrm2 and Timp3 as top candidate genes modulated by seizure activity and neuronal silencing.
View Article and Find Full Text PDFZhonghua Yi Xue Za Zhi
September 2025
Department of Respiratory and Critical Care Medicine, Qilu Hospital of Shandong University, Ji'nan 250012, China.
To investigate the mechanism by which PIWI interacting RNA piR-hsa-26925 regulates the invasion and metastasis of lung adenocarcinoma through Methyltransferase-like 3 (METTL3)-mediated m6A methylation modification. The expression levels of piR-hsa-26925 were detected in lung adenocarcinoma cell lines (H1650, H1299, H1975, and A549) and normal lung epithelial cells (BEAS-2B) using real-time fluorescent quantitative PCR (qRT-PCR). Lung adenocarcinoma cells were transfected using transient RNA transfection technology, divided into a piR-hsa-26925 knockdown group in the A549 lung adenocarcinoma cell line and a negative control (NC-1) group; the lung adenocarcinoma H1299 cell line piR-hsa-26925 overexpression group and negative control (NC-2) group.
View Article and Find Full Text PDFNat Commun
August 2025
Ecology and Evolutionary Biology Department, Columbia University, New York City, USA, NY.
Extrinsic postzygotic isolation, where hybrids experience reductions in fitness due to a mismatch with their environment, is central to speciation. Knowledge of genetic variants that underlie extrinsic isolation is crucial for understanding the early stages of speciation. Differences in seasonal migration are strong candidates for extrinsic isolation (e.
View Article and Find Full Text PDFPLoS One
August 2025
Department of Mathematics, City St George's, London, United Kingdom.
Founded in India in 2020, the microblogging site 'Koo' launched as an alternative to mainstream social media platforms, with the explicit aim of catering to non-Western communities in their vernacular languages, and capitalising on a period of tension between the Indian government and Twitter which led many users to seek Twitter-alternatives. Drawing on a near-complete dataset totalling over 71M posts and 399M user interactions, we show how Koo attracted users from several countries including India, Nigeria and Brazil, but with variable levels of sustained user engagement. We highlight how Koo's interaction network was shaped by multiple country-specific migrations displaying strong divides between linguistic and cultural communities, for instance, with English-speaking communities from India and Nigeria largely isolated from one another.
View Article and Find Full Text PDFMol Phylogenet Evol
August 2025
Laboratorio de Sistemática Molecular, Carrera de Biología, UMIEZ, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, Batalla 5 de mayo s/n, Ejército de Oriente, Ciudad de México 09230, Mexico.
The Southwestern US and northern Mexico continue to serve as ideal regions to elucidate the suite of ecological and evolutionary processes influencing lineage diversification. The complex geological history of arid North America, coupled with paleoclimate change during the Pleistocene and diverse ecoregions makes a multipronged approach to hypothesis testing necessary. We combine thousands of loci from a genotyping-by-sequencing (GBS) approach along with mitochondrial DNA (mtDNA) sequences from the Greater Earless Lizard (Cophosaurus texanus) to examine diversity and test for cryptic population structure.
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