Acquisition of dense, three-dimensional, force fields with intramolecular resolution via noncontact atomic force microscopy (NC-AFM) has yielded enormous progress in our ability to characterize molecular and two-dimensional materials at the atomic scale. To date, intramolecular force mapping has been performed exclusively at cryogenic temperatures, due to the stability afforded by low temperature operation, and as the carbon monoxide functionalization of the metallic scanning probe tip, normally required for submolecular resolution, is only stable at low temperature. In this paper we show that high-resolution, three-dimensional force mapping of a single organic molecule is possible even at room temperature. The physical limitations of room temperature operation are overcome using semiconducting materials to inhibit molecular diffusion and create robust tip apexes, while challenges due to thermal drift are overcome with atom tracking based feedforward correction. Three-dimensional force maps comparable in spatial and force resolution to those acquired at low temperature are demonstrated, permitting a quantitative analysis of the adsorption induced changes in the geometry of the molecule at the picometer level.
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http://dx.doi.org/10.1021/acsnano.2c09463 | DOI Listing |
Gait Posture
January 2025
Department of Orthopedics, Huashan Hospital, Fudan University, Shanghai, China; Academy for Engineering and Technology, Fudan University, Shanghai, China; Shanghai Sixth People's Hospital, Shanghai, China. Electronic address:
Background: Ankle joint moment and reaction force alteration after surgical treatment of chronic ankle instability (CAI) and osteochondral lesions of the talus (OLT) remains unknown.
Research Question: The current study aimed to investigate the in vivo kinetic effects of surgical management on patients with CAI and OLT and conduct a comparison with healthy subjects.
Methods: Eight patients with concurrent CAI and OLT were assessed in a stair descent setting prior to surgical management and one-year postoperatively.
J Arrhythm
February 2025
Department of Cardiology Institute of Medicine, University of Tsukuba Tsukuba Japan.
Background/objectives: Very high-power and short-duration (vHPSD) ablation with QDOT MICRO™ facilitates speedy and safe ablation for pulmonary vein isolation. A brief time interval between ablating two neighboring sites with vHPSD may potentially influence the size and geometry of the lesions. This study evaluates lesion formation when delivering adjacent applications using vHPSD at various inter-lesion times (ILTs).
View Article and Find Full Text PDFFront Parasitol
December 2023
Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.
Reticulocyte Binding Protein Homologue (RH5), a leading malaria vaccine candidate, is essential for erythrocyte invasion by the parasite, interacting with the human host receptor, basigin. RH5 has a small number of polymorphisms relative to other blood-stage antigens, and studies have shown that vaccine-induced antibodies raised against RH5 are strain-transcending, however most studies investigating RH5 diversity have been done in Africa. Understanding the genetic diversity and evolution of malaria antigens in other regions is important for their validation as vaccine candidates.
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States.
We report a Tuning Fork Scanning Electrochemical Cell Microscopy (TF-SECCM) technique for providing morphological and electrochemical information on single redox-active entities. This new operation configuration of SECCM utilizes an electrolyte-filled nanopipette tip mounted onto a tuning fork force sensor to obtain a precise tip-sample distance control and surface morphological mapping capabilities. Redox activities of regions of interest (ROIs) can be investigated by scanning electrode potential by moving the nanopipette to any target regions while maintaining the constant force engagement of the tip with the sample.
View Article and Find Full Text PDFJ Chem Phys
January 2025
Institute of Thermodynamics and Thermal Process Engineering, University of Stuttgart, Pfaffenwaldring 9, D-70569 Stuttgart, Germany.
Effective potential methods, obtained by applying a quantum correction to a classical pair potential, are widely used for describing the thermophysical properties of fluids with mild nuclear quantum effects. In case of strong nuclear quantum effects, such as for liquid hydrogen and helium, the accuracy of these quantum corrections deteriorates significantly, but at present no simple alternatives are available. In this work, we solve this issue by developing a new, three-parameter corresponding-states principle that remains applicable in the regions of the phase diagram where quantum effects become significant.
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