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Self‐propelled particles and, in particular, those based on mesoporous silica, have raised considerable interest due to their potential applications in the environmental and biomedical fields thanks to their biocompatibility, tunable surface chemistry and large porosity. Although spherical particles have been widely used to fabricate nano‐ and micromotors, not much attention has been paid to other geometries, such as nanorods. Here, we report the fabrication of self‐propelled mesoporous silica nanorods (MSNRs) that move by the catalytic decomposition of hydrogen peroxide by a sputtered Pt layer, Fe2O3 nanoparticles grown within the mesopores, or the synergistic combination of both. We show that motion can occur in two distinct sub‐populations characterized by two different motion dynamics, namely enhanced diffusion or directional propulsion, especially when both catalysts are used. These results open up the possibility of using MSNRs as chassis for the fabrication of self‐propelled particles for the environmental or biomedical fields., R.M. thanks “la Caixa” Foundation through IBEC International PhD Programme “la Caixa” Severo Ochoa fellowships (code LCF/BQ/SO16/52270018). A.C.H. thanks MINECO for the Severo Ochoa PhD fellowship. J.G. has received financial support through the “la Caixa” INPhINIT Fellowship Grant for Doctoral Studies at Spanish Research Centers of Excellence (Grant code: LCF/BQ/DI17/11620041), “la Caixa” Banking Foundation (ID100010434), Barcelona, Spain. The CERCA program by the Generalitat de Catalunya, the Secretaria d′Universitats i Recerca del Departament d′Empresa i Coneixement de la Generalitat de Catalunya through the projects 2017SGR1148 & 2017SGR765 are acknowledged, as well as the Ministerio de Ciencia, Innovación y Universidades (MCIU)/Agencia Estatal de Investigación (AEI)/Fondo Europeo de Desarrollo Regional (FEDER, UE) through the projects RTI2018‐098164‐B‐I00 & RTI2018‐096273‐B‐I00 and Severo Ochoa Programme for Centres of Excellence in R&D (CEX2019‐000917‐S and CEX2018‐000789‐S). This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 866348).

Objectives/hypothesis The goal of this study was to objectively examine vocal fold (VF) motion dynamics after iatrogenic recurrent laryngeal nerve (RLN) injury in a mouse surgical model. Furthermore, we sought to identify a method of inducing injury with a consistent recovery pattern from which we can begin to evaluate spontaneous recovery and test therapeutic interventions. Study design Animal model. Methods The right RLN in C57BL/6J mice was crushed for 30 seconds using an aneurysm clip with 1.3-N closing force. Transoral laryngoscopy enabled visualization of VF movement prior to surgery, immediately post-crush, and at two endpoints: 3 days (n = 5) and 2 weeks (n = 5). VF motion was quantified with our custom motion-analysis software. At each endpoint, RLN samples were collected for transmission electron microscopy for correlation with VF motion dynamics. Results Our VF tracking software permitted automated quantification of several measures of VF dynamics, such as range and frequency of motion. By 2 weeks post-injury, the frequency of VF movement on the right (injured) side equaled the left, yet range of motion only partially recovered. These objective outcome measures enabled detection of VF dysfunction that persisted at 2 weeks post-crush. Transmission electron microscopy images revealed RLN degeneration 3 days post-crush and partial regeneration at 2 weeks, consistent with functional results obtained with automated VF tracking. Conclusions Our motion-analysis software provides novel objective, quantitative, and repeatable metrics to detect and describe subtle VF dysfunction in mice that corresponds with underlying RLN degeneration and recovery. Adaptation of our tracking software for use with human patients is underway. Level of evidence NA Laryngoscope, 129:E247-E254, 2019.

This paper presents analytical models to investigate the steering maneuvers of planetary exploration rovers on loose soil. The models are based on wheel-soil interaction mechanics, or terramechanics, with which the traction and disturbance forces of a wheel are evaluated for various slip conditions. These traction forces are decomposed into the longitudinal and lateral directions of the wheel. The latter component, termed the side force has a major influence in characterizing the steering maneuvers of the rover. In this paper, the wheel-soil mechanics models are developed with particular attention to the side force and the validity of the model is confirmed by using a single-wheel test bed. The motion profile of the entire rover is numerically evaluated by incorporating the wheel-soil models into an articulated multibody model that describes the motion dynamics of the vehicle’s body and chassis. Steering maneuvers are investigated under different steering angles by using a four-wheel rover test bed on simulated lunar soil regolith simulant. The experimental results are compared with the simulation results using the corresponding model parameters. The proposed wheel-and-vehicle model demonstrates better accuracy in predicting steering maneuvers as compared to the conventional kinematics-based model. ©

This paper presents a dynamics-based Effort simulator so that a given motion can be modified according to specified Effort qualities. The basic idea of our approach is to establish relations between Effort factors such as Space, Weight, Time, and Flow, and their corresponding dynamics parameters such as force, stiffness, inertia, damping, gravity, and etc in the simulator. Then, a motion with specified Effort quality can be realized by mapping it to appropriate dynamics parameters of the simulator. The proposed simulator has two merits: it is motion capture-driven, therefore it is able to synthesize motion details and easily to be incorporated into popular motion capture applications. Besides, it is dynamics based and therefore it provides high-level control intuition of motion dynamics in specifying Effort qualities. To demonstrate the effectiveness of the proposed simulator, several experimental examples are presented and their results are discussed. Copyright © 2006 John Wiley & Sons, Ltd.