Cross-sections were prepared by ultramicrotome (UM) and focused ion beam (FIB) system in order to examine the skeletal structure of ecologically and geologically important shell-bearing protists: phaeodarians and radiolarians. The elemental composition of the skeleton was clarified by the energy dispersive X-ray spectroscopy, suggesting that the skeletons of both groups are mainly made of amorphous silica (SiO·nHO) with other minor elements (Na, Mg, Al, Cl, K, Ca and Fe) and that these two groups have similar elemental composition, compared with other siliceous organisms (diatoms and sponges). However, the structural difference among the two groups was confirmed: phaeodarian skeletons are porous, unlike radiolarians with solid skeletons. It was also revealed that the phaeodarian skeleton contains concentric layered structure with spaces, presumably related to the ontogenetic skeleton formation. The distinction in the skeletal ultrafine structure (porous/solid and non-dense/dense) would reflect the ecological difference among the two groups and could be an effective criterion to determine whether microfossils belong to Radiolaria or Phaeodaria. The UM and FIB combined method presented in this study could be a useful approach to examine the chemical and structural characteristics of unculturable and/or rare microorganisms.
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http://dx.doi.org/10.1016/j.jsb.2018.06.008 | DOI Listing |
J Basic Microbiol
January 2025
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia.
One of the main difficulties in nanotechnology is the development of an environmentally friendly, successful method of producing nanoparticles from biological sources. Silver-doped zinc oxide nanoparticles (Ag-ZnO NPs), with antibacterial and antioxidant properties, were produced using Adiantum venustum extract as a green technique. Fresh A.
View Article and Find Full Text PDFRapid Commun Mass Spectrom
April 2025
Department of Civil and Environmental Engineering, Syracuse University, Syracuse, New York, USA.
Rationale: The complexation with dissolved organic matter (DOM) is a pivotal factor influencing transformations, transport, and bioavailability of mercury (Hg) in aquatic environments. However, identifying these complexes poses a significant challenge because of their low concentrations and the presence of coexisting ions.
Methods: In this study, mercury-dissolved organic matter (Hg-DOM) complexes were isolated through solid-phase extraction (SPE) from Hg-humic acid suspensions, and complexes were putatively identified using ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS).
Soil nutrients and meteorological conditions are pivotal environmental factors influencing plant growth and development. This study systematically analyzes how soil nutrients and meteorological factors influence the phenotypic growth and seed production of wild Elymus nutans in Tibet. These environmental factors are critical ecological determinants, and this research seeks to unveil the complex and diverse ecological adaptation mechanisms of the species.
View Article and Find Full Text PDFNat Commun
January 2025
Key Laboratory of Automobile Materials, Ministry of Education, Department of Materials Science and Engineering, Jilin University, 130022, Changchun, China.
Correlating the bond strength with the macro strength of metals is crucial for understanding mechanical properties and designing multi-principal-element alloys (MPEAs). Motivated by the role of grain boundaries in the strength of metals, we introduce a predictive model to determine the grain-boundary energies and strength of metals from the cohesive energy and atomic radius. This scheme originates from the d-band characteristics and broken-bond spirit of tight-binding models, and demonstrates that the repulsive/attractive effects play different roles in the variation of bond strength for different metals.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Pharmaceutical Science, Faculty of Pharmacy, Umm Al-Qura University, Makkah, P.O. Box 751, Saudi Arabia.
This study presents the synthesis and application of water-ball (sodium polyacrylate) stabilized zero-valent iron nanoparticles (wb@Fe) for the eco-friendly degradation of Methyl Orange (MO). The nanoparticles were prepared using a chemical reduction method using NaBH. Characterization techniques including Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS), and X-ray Diffraction (XRD) were employed to analyze the morphology, elemental composition, valent state and crystallinity of the nanoparticles.
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