The number, morphology and elemental composition of nanoparticles (<100 nm) in marine water was investigated using Variable Pressure Scanning Electron Microscopy (VP-SEM) and Energy-dispersive X-ray spectroscopy (EDS). Preliminary research conducted in the Baltic Sea showed that the number of nanoparticles in seawater varied from undetectable to 380 (x10) cm. Wind mixing and density barriers (thermocline) had a significant impact on the abundance and distribution of nanoparticles in water. Many more nanoparticles (mainly nanofibers) were detected in periods of intensive primary production and thermal stratification of water than at the end of the growing season and during periods of strong wind mixing. Temporal and spatial variability of nanoparticles as well as air mass trajectories indicated that the analysed nanofibers were both autochthonous and allochthonous (atmospheric), while the nanospheres were mainly autochthonous. Chemical composition of most of analysed nanoparticles indicates their autochthonous, natural (biogenic/geogenic) origin. Silica nanofibers (probably the remains of flagellates), nanofibers composed of manganese and iron oxides (probably of microbial origin), and pyrite nanospheres (probable formed in anoxic sediments), were all identified in the samples. Only asbestos nanofibers, which were also detected, are probably allochthonous and anthropogenic.
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http://dx.doi.org/10.1016/j.chemosphere.2018.05.022 | DOI Listing |
PLoS One
January 2025
Department of Physiology, Biophysics, and Neurosciences; Center for Research and Advanced Studies (Cinvestav), Mexico City, Mexico.
The mechanisms underlying the establishment of asymmetric structures during development remain elusive. The wing of Drosophila is asymmetric along the Anterior-Posterior (AP) axis, but the developmental origins of this asymmetry is unknown. Here, we investigate the contribution of cell recruitment, a process that drives cell fate differentiation in the Drosophila wing disc, to the asymmetric shape and pattern of the adult wing.
View Article and Find Full Text PDFGenome Biol
January 2025
College of Life Sciences, Key Laboratory of Animal Reproduction and Biotechnology in Universities of Shandong, Qingdao Agricultural University, Qingdao, 266109, China.
Background: In humans and other mammals, the process of oogenesis initiates asynchronously in specific ovarian regions, leading to the localization of dormant and growing follicles in the cortex and medulla, respectively; however, the current understanding of this process remains insufficient.
Results: Here, we integrate single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (ST) to comprehend spatial-temporal gene expression profiles and explore the spatial organization of ovarian microenvironments during early oogenesis in pigs. Projection of the germ cell clusters at different stages of oogenesis into the spatial atlas unveils a "cortical to medullary (C-M)" distribution of germ cells in the developing porcine ovaries.
Methods Mol Biol
January 2025
Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid, Spain.
StarTrack is a powerful multicolor genetic tool designed to unravel cellular lineages arising from neural progenitor cells (NPCs). This innovative technique, based on retrospective clonal analysis and built upon the PiggyBac system, creates a unique and inheritable "color code" within NPCs. Through the stochastic integration of 12 distinct plasmids encoding six fluorescent proteins, StarTrack enables precise and comprehensive tracking of cellular fates and progenitor potentials.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Translational Medical Sciences, School of Medicine, Texas A&M Health Science Center, Texas A&M University, Houston, TX 77030.
Induction of cell fates by growth factors impacts many facets of developmental biology and disease. LIN-3/EGF induces the equipotent vulval precursor cells (VPCs) in to assume the 3˚-3˚-2˚-1˚-2˚-3˚ pattern of cell fates. 1˚ and 2˚ cells become specialized epithelia and undergo stereotyped series of cell divisions to form the vulva.
View Article and Find Full Text PDFJ Mol Evol
December 2024
Department of Zoology, Hansraj College, University of Delhi, Mahatma Hansraj Marg, Malkaganj, Delhi, 110007, India.
The urgency to understand the complex interactions between viruses, their animal reservoirs, and human populations has been necessitated by the continuous spread of zoonotic viral diseases as evidenced in epidemics and pandemics throughout human history. Riboviruses are involved in some of the most prevalent human diseases, responsible for causing epidemics and pandemics. These viruses have an animal origin and have been known to cross the inter-species barrier time and time again, eventually infecting human beings.
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