Wearing a surgical mask does not affect the anaerobic threshold during pedaling exercise

The effect of wearing a surgical mask on cardiopulmonary function and anaerobic threshold (AT) has not been reported. Thus, we aimed to determine whether cardiopulmonary function and AT vary while wearing surgical masks. Six healthy men were enrolled and underwent the cardiopulmonary exercise (CPX) stress test under two different conditions (with and without a commercially available surgical mask) to evaluate their AT. To confirm that there was no breath leakage, a gas mask connected with a respiratory gas analyser was worn over the surgical mask when the participants performed the CPX. The AT was measured by the V-slope method. Moreover, the AT time, exercise load, oxygen consumption, and ventilation values after the CPX were determined. No significant differences were found between the two conditions. The number of complaints of respiratory distress, however, was significantly higher while wearing a surgical mask. The exercise intensity achieved by each participant was equivalent, irrespective of whether they wore the surgical mask; therefore, wearing a surgical mask does not affect cardiopulmonary function during vigorous exercise

Geometric trade-off between contractile force and viscous drag determines the actomyosin-based motility of a cell-sized droplet

動きまわる人工細胞、その鍵は摩擦にあり --細胞が狭い空間を利用して運動する仕組みを解明--. 京都大学プレスリリース. 2022-07-21.Cell migration in confined environments is fundamental for diverse biological processes from cancer invasion to leukocyte trafficking. The cell body is propelled by the contractile force of actomyosin networks transmitted from the cell membrane to the external substrates. However, physical determinants of actomyosin-based migration capacity in confined environments are not fully understood. Here, we develop an in vitro migratory cell model, where cytoplasmic actomyosin networks are encapsulated into droplets surrounded by a lipid monolayer membrane. We find that the droplet can move when the actomyosin networks are bound to the membrane, in which the physical interaction between the contracting actomyosin networks and the membrane generates a propulsive force. The droplet moves faster when it has a larger contact area with the substrates, while narrower confinement reduces the migration speed. By combining experimental observations and active gel theory, we propose a mechanism where the balance between sliding friction force, which is a reaction force of the contractile force, and viscous drag determines the migration speed, providing a physical basis of actomyosin-based motility in confined environments

Carbon-rich materials with three-dimensional ordering at the angstrom level

Carbon-rich materials, which contain over 90% carbon, have been mainly synthesized by the carbonization of organic compounds. However, in many cases, their original molecular and ordered structures are decomposed by the carbonization process, which results in a failure to retain their original three-dimensional (3D) ordering at the angstrom level. Recently, we successfully produced carbon-rich materials that are able to retain their 3D ordering at the angstrom level even after the calcination of organic porous pillar[6]arene supramolecular assemblies and cyclic porphyrin dimer assemblies. Other new pathways to prepare carbon-rich materials with 3D ordering at the angstrom level are the controlled polymerization of designed monomers and redox reaction of graph. Electrocatalytic application using these materials is described

Bipedal Robot Running: Human-like Actuation Timing Using Fast and Slow Adaptations

We have been developing human-sized biped robots based on passive dynamic mechanisms. In human locomotion, the muscles activate at the same rate relative to the gait cycle during running. To achieve adaptive running for robots, such characteristics should be reproduced to yield the desired effect. In this study, we designed a central pattern generator (CPG) involving fast and slow adaptation to achieve human-like running using a simple spring-mass model and our developed bipedal robot, which is equipped with actuators that imitate the human musculoskeletal system. Our results demonstrate that fast and slow adaptations can reproduce human-like running with a constant rate of muscle firing relative to the gait cycle. Furthermore, the results suggest that the CPG contributes to the adjustment of the muscle activation timing in human running.Comment: 15 pages, 12 figures, submitted to Advanced Robotic

Satellite Software Development Framework With Rust That Improves Developer Enablement

Our challenge: developing various satellites with a small team in a short perio

Yeast Eps15-like endocytic protein Pan1p regulates the interaction between endocytic vesicles, endosomes and the actin cytoskeleton

The actin cytoskeleton plays important roles in the formation and internalization of endocytic vesicles. In yeast, endocytic vesicles move towards early endosomes along actin cables, however, the molecular machinery regulating interaction between endocytic vesicles and actin cables is poorly understood. The Eps15-like protein Pan1p plays a key role in actin-mediated endocytosis and is negatively regulated by Ark1 and Prk1 kinases. Here we show that pan1 mutated to prevent phosphorylation at all 18 threonines, pan1-18TA, displayed almost the same endocytic defect as ark1Δ prk1Δ cells, and contained abnormal actin concentrations including several endocytic compartments. Early endosomes were highly localized in the actin concentrations and displayed movement along actin cables. The dephosphorylated form of Pan1p also caused stable associations between endocytic vesicles and actin cables, and between endocytic vesicles and endosomes. Thus Pan1 phosphorylation is part of a novel mechanism that regulates endocytic compartment interactions with each other and with actin cables