Prokaryotic maintenance respiration and associated metabolic activities constitute a considerable proportion of the total respiration of carbon to CO2 in the ocean's mixed layer. However, seasonal influences on prokaryotic maintenance activities in terms of morphological and metabolic adaptations at low (winter) and high productivity (summer) are still unclear. To address this, we examined the natural prokaryotic communities at the mesocosm scale to analyse the differences in their morphological features and gene expression at low and high maintenance respiration, experimentally manipulated with the specific growth rate.
View Article and Find Full Text PDFScanning electron microscopy (SEM) can reveal the ultrastructure of bacterial spores, including morphology, surface features, texture, spore damage, germination, and appendages. Understanding these features can provide a basis for adherence, how physical and environmental stressors affect spore viability, integrity, and functionality, as well as the distribution and function of surface appendages. However, the spore sample preparation method can significantly impact the SEM images' appearance, resolution, and overall quality.
View Article and Find Full Text PDFThe biopolymer lignin is deposited in the cell walls of vascular cells and is essential for long-distance water conduction and structural support in plants. Different vascular cell types contain distinct and conserved lignin chemistries, each with specific aromatic and aliphatic substitutions. Yet, the biological role of this conserved and specific lignin chemistry in each cell type remains unclear.
View Article and Find Full Text PDFGlendonites have been found worldwide in marine sediments from the Neoproterozoic Era to the Quaternary Period. The precursor of glendonite, ikaite (CaCO · 6HO), is metastable and has only been observed in nature at temperatures <7 °C. Therefore, glendonites in the sedimentary record are commonly used as paleotemperature indicators.
View Article and Find Full Text PDFBackground: Immunogold labeling in combination with transmission electron microscopy analysis is a technique frequently used to correlate high-resolution morphology studies with detailed information regarding localization of specific antigens. Although powerful, the methodology has limitations and it is frequently difficult to acquire a stringent system where unspecific low-affinity interactions are removed prior to analysis.
Results: We here describe a combinatorial strategy where surface plasmon resonance and immunogold labeling are used followed by a direct analysis of the sensor-chip surface by scanning electron microscopy.
Earth-abundant cobalt-doped hematite thin-film electrocatalysts were explored for acidic water oxidation. The strategically doped hematite produced a stable geometric current density of 10 mA cm-2 for up to 50 h at pH 0.3, as a result of Co-enhanced intrinsic catalytic activity and charge transport properties across the film matrix.
View Article and Find Full Text PDFWe demonstrate the use of Scanning Electron microscopy (SEM) in combination with Surface Plasmon Resonance (SPR) to probe and verify the formation of amyloid and its morphology on an SPR chip. SPR is a technique that measures changes in the immobilized weight on the chip surface and is frequently used to probe the formation and biophysical properties of amyloid structures. In this context it is of interest to also monitor the morphology of the formed structures.
View Article and Find Full Text PDFFibril formation of the amyloid-β peptide (Aβ) follows a nucleation-dependent polymerization process and is associated with Alzheimer's disease. Several different lengths of Aβ are observed in vivo, but Aβ1-40 and Aβ1-42 are the dominant forms. The fibril architectures of Aβ1-40 and Aβ1-42 differ and Aβ1-42 assemblies are generally considered more pathogenic.
View Article and Find Full Text PDFEngineering the electronic properties of transition metal phosphides has shown great effectiveness in improving their intrinsic catalytic activity for the hydrogen evolution reaction (HER) in water splitting applications. Herein, we report for the first time, the creation of Fe vacancies as an approach to modulate the electronic structure of iron phosphide (FeP). The Fe vacancies were produced by chemical leaching of Mg that was introduced into FeP as "sacrificial dopant".
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