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Understanding chemical reactivity and magnetism of 3d transition metal nanoparticles is of fundamental interest for applications in fields ranging from spintronics to catalysis. Here, we present an atomistic picture of the early stage of the oxidation mechanism and its impact on the magnetism of Co nanoparticles. Our experiments reveal a two-step process characterized by (i) the initial formation of small CoO crystallites across the nanoparticle surface, until their coalescence leads to structural completion of the oxide shell passivating the metallic core; (ii) progressive conversion of the CoO shell to CoO and void formation due to the nanoscale Kirkendall effect. The Co nanoparticles remain highly reactive toward oxygen during phase (i), demonstrating the absence of a pressure gap whereby a low reactivity at low pressures is postulated. Our results provide an important benchmark for the development of theoretical models for the chemical reactivity in catalysis and magnetism during metal oxidation at the nanoscale.
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http://dx.doi.org/10.1038/s41467-023-35846-0 | DOI Listing |
High Blood Press Cardiovasc Prev
September 2025
Department of Cardiology, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Blood pressure variability (BPV), independent of mean BP, is an emerging predictor of cardiovascular risk and hypertension-mediated organ damage. However, its clinical utility remains limited due to the lack of clear guideline recommendations, leading to variability in physician practices. Using the modified Delphi method, this is the first Egyptian consensus to provide expert recommendations for integrating BPV in Egypt's resource-limited settings.
View Article and Find Full Text PDFFront Neurol
August 2025
Otolaryngology-Head and Neck Surgery, The Ohio State University Wexner Medical Center, Columbus, OH, United States.
Introduction: External continuous perturbations using a motion platform have been developed by employing either sum-of-sines (SoS) or a pseudorandom ternary sequence (PRTS) of numbers to quantify body sway evoked in the medial-lateral (ML) or anterior-posterior (AP) directions, which ultimately helps understand the human postural control system. These stimuli have been provided via pitch tilts of the motion platform for evaluations of AP balance responses or roll tilts for ML balance responses. However, little is known about whether a healthy postural control system responds to 2-dimensional (2D) perturbations similarly when the perturbation stimuli are provided in semicircular canal coordinates (i.
View Article and Find Full Text PDFFront Sports Act Living
August 2025
School of Physical Education, Zhejiang Guangsha Vocational and Technical University of Construction, Dongyang, China.
Introduction: This study examined the impacts of different negative pressure cupping therapies (PCT) on pain relief, functional recovery, and inflammatory regulation in delayed onset muscle soreness (DOMS) after high-intensity exercise, with the aim of clarifying the dose-effect relationship.
Methods: In this study, 55 healthy male participants aged 18-25 were selected and divided into 5 groups: the control group (CTR; = 11) and NPCT groups at different levels (-25 kPa, -35 kPa, -45 kPa, and -55 kPa; = 11 in each group). A high-intensity protocol, which included 6 sets of lunges, squats, and squat jumps, was adopted to induce DOMS in the quadriceps femoris.
Front Med (Lausanne)
August 2025
Department of Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Background: In critically ill patients with septic shock, adequate oxygenation is crucial and hypoxia should be avoided. However, hyperoxia has been linked to the formation of reactive oxygen species, inflammation, and vasoconstriction, which could potentially harm critically ill intensive care patients. Therefore, this study aimed to examine the association between oxygen exposure and mortality and to define optimal oxygen target ranges for this specific group of patients.
View Article and Find Full Text PDFFront Med (Lausanne)
August 2025
Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
Purpose: To investigate the mechanism, intraoperative characteristics, management, and prevention of incision capsular bag herniation (ICBH), a previously unreported complication during cataract surgery in eyes with lens subluxation.
Methods: A retrospective observational case series was conducted on five male patients who developed ICBH during phacoemulsification with intraocular lens (IOL) implantation between January 2019 and December 2024. Among 867 subluxated-lens surgeries performed during this period, the estimated incidence of ICBH was 0.