98%
921
2 minutes
20
In this work, the tip convolution effect in atomic force microscopy is revisited to illustrate the capabilities of cubic objects for determination of the tip shape and size. Using molecular-based cubic nanoparticles as a reference, a two-step tip reconstruction process has been developed. First, the tip-to-face angle is estimated by means of an analysis of the convolution error while the tip radius is extracted from the experimental profiles. The results obtained are in good agreement with specification of the tip supplier even though the experiments have been conducted using real distribution of nanoparticles with dispersion in size and aspect ratio. This demonstrates the reliability of our method and opens the door for a more accurate tip reconstruction by using calibration standards.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7641199 | PMC |
http://dx.doi.org/10.1038/s41598-020-75785-0 | DOI Listing |
Probiotics Antimicrob Proteins
September 2025
School of Life Science, Liaoning Normal University, Dalian, 116081, China.
Cutibacterium acnes (C. acnes, formerly classified as Propionibacterium acnes) is a Gram-positive bacterium that contributes to the development of acne vulgaris, resulting in inflammation and pustule formation on the skin. In this study, we developed and synthesized a series of antimicrobial peptides (AMPs) that are derived from the skin secretion of Rana chensinensis.
View Article and Find Full Text PDFMed Oncol
September 2025
Venom and Biotherapeutics Molecules Laboratory, Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
Neuropeptide Y (NPY) and the voltage-gated potassium channel Kv1.3 are closely associated with breast cancer progression and apoptosis regulation, respectively. NPY receptors (NPYRs), which are overexpressed in breast tumors, contribute to tumor growth, migration, and angiogenesis.
View Article and Find Full Text PDFNucleic Acids Res
September 2025
Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic.
RNA G-quadruplexes (rG4s) are emerging as vital structural elements involved in processes like gene regulation, translation, and genome stability. Found in untranslated regions of messenger RNAs (mRNAs), they influence translation efficiency and mRNA localization. Additionally, rG4s of long noncoding RNAs and telomeric RNA play roles in RNA processing and cellular aging.
View Article and Find Full Text PDFJ Chem Phys
September 2025
Department of Mathematics and Computer Science, Freie Universität, Berlin, Germany.
Coarse-grained (CG) molecular dynamics simulations extend the length and time scales of atomistic simulations by replacing groups of correlated atoms with CG beads. Machine-learned coarse-graining (MLCG) has recently emerged as a promising approach to construct highly accurate force fields for CG molecular dynamics. However, the calibration of MLCG force fields typically hinges on force matching, which demands extensive reference atomistic trajectories with corresponding force labels.
View Article and Find Full Text PDFJ Chem Theory Comput
September 2025
Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark.
The minimal basis iterative Stockholder (MBIS) decomposition of molecular electron densities into atomic contributions is extended from spherical to ellipsoidal atomic basins. Despite the more flexible parametrization, the derived atomic multipole moments do not systematically improve the reproduction of molecular multipole moments and electrostatic potentials relative to a decomposition into spherical atomic densities. The decomposition can be constrained to exactly reproduce molecular multipole moments, in the present work extended up to hexadecapole moments, and this slightly improves the ability to reproduce the electrostatic potential.
View Article and Find Full Text PDF