Internal Propulsion Research Articles

Shouhui Tongbian Capsules induce regression of inflammation to improve intestinal barrier in mice with constipation by targeted binding to Prkaa1: With no obvious toxicity

Constipation arising from the poor bowel movement is a rife enteric health problem. Shouhui Tongbian Capsule (SHTB) is a traditional Chinese medicine (TCM) which effectively improve the symptoms of constipation. However, the mechanism has not been fully evaluated. The purpose of this study was to evaluate the effect of SHTB on the symptoms and intestinal barrier of mice with constipation. Our data showed that SHTB effectively improved the constipation induced by diphenoxylate, which was confirmed by shorter first defecation time, higher internal propulsion rate and fecal water content. Additionally, SHTB improved the intestinal barrier function, which was manifested by inhibiting the leakage of Evans blue in intestinal tissues and increasing the expression of occludin and ZO-1. SHTB inhibited NLRP3 inflammasome signaling pathway and TLR4/NF-κB signaling pathway, reduced the number of proinflammatory cell subsets and increased the number of immunosuppressive cell subsets to relieve inflammation. The photochemically induced reaction coupling system combined with cellular thermal shift assay and central carbon metabolomics technology confirmed that SHTB activated AMPKα through targeted binding to Prkaa1 to regulate Glycolysis/Gluconeogenesis and Pentose Phosphate Pathway, and finally inhibited intestinal inflammation. Finally, no obvious toxicity related to SHTB was found in a repeated drug administration toxicity test for consecutive 13 weeks. Collectively, we reported SHTB as a TCM targeting Prkaa1 for anti-inflammation to improve intestinal barrier in mice with constipation. These findings broaden our knowledge of Prkaa1 as a druggable target protein for inflammation inhibition, and open a new avenue to novel therapy strategy for constipation injury.

Narrow Weld Joint Recognition Method Based on Laser Profile Sensor

Intelligent manufacturing technology has recently experienced rapid development, where robot welding systems are an essential component. A laser profile sensor is commonly utilized in intelligent robot welding systems. However, when the laser stripe is projected onto a narrow weld joint, the deformation of the laser stripe is not sufficiently apparent, and the traditional weld joint recognition methods based on the laser profile sensors cannot detect the narrow weld joint position. Meanwhile, the strong arc and spatter noise during welding and the expansion of weld joint width caused by welding thermal expansion are likely to interfere with weld joint recognition. In addition, many common weld seam recognition methods can only recognize certain weld joints and have limited flexibility and robustness for other types of weld joints. This study proposes a wide range of weld joint recognition algorithms based on the laser profile sensor to overcome these challenges. The gray value histogram analysis method, the adaptive threshold method, the internal propulsion center and boundary extraction (IPCBE) method, the coordinate analysis method, and the stripe end center detection method proposed in this study are used primarily in the algorithm. The algorithm solves the problem of identifying narrow weld joints and allows for the identification of larger conventional weld joints. Furthermore, the algorithm has good a anti-spatter and anti-arc interference ability and a fast speed, allowing it to meet the demand for real-time welding identification.

Internal Propulsion Algorithm for Extracting Center of Line Laser Stripe

Internal Propulsion Algorithm for Extracting Center of Line Laser Stripe

One-dimensional displacement of active matter on curved substrates

We analytically find the diffusion of overdamped active Brownian particles (ABPs) constrained to move along curved one-dimensional channels. The autonomous motion of these particles is achieved by a projection of their internal propulsion force along the channels' long section. In particular, the diffusion of ABPs moving on one-dimensional channels with a form of a circle, an ellipse, and a limacon of second order is analysed. To characterise the effect of substrate's geometry and self-propulsion on their diffusion, analytical expressions for the ABPs short- and long-time variances, as well as their steady angular probability density functions are offered. Curvature effects are found to reduce the time an ABP reaches its steady state. Our theoretical results are validated using Brownian dynamics simulations. This model may be relevant for experiments dealing with catalytic driven systems, bacteria, and tumour cell dispersion in one-dimensional channels.

Magnetic Biohybrid Vesicles Transported by an Internal Propulsion Mechanism.

Some biological microorganisms can crawl or swim due to coordinated motions of their cytoskeleton or the flagella located inside their bodies, which push the cells forward through intracellular forces. To date, there is no demonstration of synthetic systems propelling at low Reynolds number via the precise actuation of the material confined within an enclosing lipid membrane. Here, we report lipid vesicles and other more complex self-assembled biohybrid structures able to propel due to the advection flows generated by the actuated rotation of the superparamagnetic particles they contain. The proposed swimming and release strategies, based on cooperative hydrodynamic mechanisms and near-infrared laser pulse-triggered destabilization of the phospholipid membranes, open new possibilities for the on-command transport of minute quantities of drugs, fluidor nano-objects. The lipid membranes protect the confined substances from the outside environment during transportation, thus enabling them to work in physiological conditions.

Numerical analysis of air flow past an unmanned aerial vehicle with internal propulsion system

Numerical analysis of air flow past an unmanned aerial vehicle with internal propulsion system

Extreme fluctuations of active Brownian motion

In active Brownian motion, an internal propulsion mechanism interacts with translational and rotational thermal noise and other internal fluctuations to produce directed motion. We derive the distribution of its extreme fluctuations and identify its universal properties using large deviation theory. The limits of slow and fast internal dynamics give rise to a kink-like and parabolic behavior of the corresponding rate functions, respectively. For dipolar Janus particles in two- and three-dimensions interacting with a field, we predict a novel symmetry akin to, but different from, the one related to entropy production. Measurements of these extreme fluctuations could thus be used to infer properties of the underlying, often hidden, network of states.

Dynamics Control of Pendulums Driven Spherical Robot

The pendulum driven spherical robot exhibit unique dynamic behavior which designed for reconnaissance and unstructured hostile environment exploration. Unfortunately spherical type robot maneuvering is nonlinear to get the desired part, internal propulsion mechanism and motion control need to be reconciled. This is a mechanical challenge to get in balancing and weight distribution. The robot has three DOFs and single inputs, of which the nature is a nonlinear and under actuated system with non-holonomic dynamic constraints. The enhanced construction of two sections on pendulums joint offers novel motion principle of spherical robot, which is moving simultaneously actuated by eccentric moment and inertial moment generated by this pendulum. Meanwhile the mobility is enhanced when the robot behaves dynamically. The dynamic model of linear motion is formulated on the basis of Lagrange equation, and a smooth trajectory planning method is proposed for linear motion. A feedback controller is build to ensure the accurate trajectory planning. Turning in place motion is an indispensable element of omni directional locomotion which can enhance the mobility of spherical robots. The dynamic model is derived using the theory of moment of momentum, and a stick-slip principle is analyzed. The two motion control methods are validated by both simulations and prototype experiments.

Brownian diode: Molecular motor based on a semi-permeable Brownian particle with internal potential drop

A model of an autonomous isothermal Brownian motor with an internal propulsion mechanism is considered. The motor is a Brownian particle which is semi-transparent for molecules of surrounding ideal gas. Molecular passage through the particle is controlled by a potential similar to that in the transition rate theory, i.e. characterized by two stationary states with a finite energy difference separated by a potential barrier. The internal potential drop maintains the diode-like asymmetry of molecular fluxes through the particle, which results in the particle's stationary drift.

Numerical Analysis of Air Flow Past the 2415-3S Airfoil for an Unmanned Aerial Vehicle with Internal Propulsion System

This paper deals with the prediction of pressure and velocity fields on the 2415-3S airfoil which will be used for and unmanned aerial vehicle with internal propulsion system and in this way analyze the air flow through an internal duct of the airfoil using computational fluid dynamics. The main objective is to evaluate the effect of the internal air flow past the airfoil and how this affects the aerodynamic performance by means of lift and drag forces. For this purpose, three different designs of the internal duct were studied; starting from the base 2415-3S airfoil developed in previous investigation, basing on the hypothesis of decreasing the flow separation produced when the propulsive airflow merges the external flow, and in this way obtaining the best configuration. For that purpose, an exhaustive study of the mesh sensitivity was performed. It was used a non-structured mesh since the computational domain is tridimensional and complex. The selected mesh contains approximately 12.5 million elements. Both the computational domain and the numerical solution were made with commercial CAD and CFD software respectively. Air, incompressible and steady was analyzed. The boundary conditions are in concordance with experimental setup in the AF 6109 wind tunnel. The k-e model is utilized to describe the turbulent flow process as followed in references. Results allowed obtaining pressure and velocity contours as well as lift and drag coefficients and also the location of separation and reattachment regions in some cases for zero degrees of angle of attack on the internal and external surfaces of the airfoil. Finally, the selection of the configuration with the best aerodynamic performance was made, selecting the option without curved baffles.

Experimental measurement of the aerodynamic charateristics of two-dimensional airfoils for an unmanned aerial vehicle

• , Jii NOŽIKA, Jan VAVIN Abstract: This paper is part of the development of an airfoil for an unmanned aerial vehicle (UAV) with internal propulsion system; the investigation involves the analysis of the aerodynamic performance for the gliding condition of two-dimensional airfoil models which have been tested. This development is based on the modification of a selected airfoil from the NACA four digits family. The modification of this base airfoil was made in order to create a blowing outlet with the shape of a step on the suction surface since the UAV will have an internal propulsion system. This analysis involved obtaining the lift, drag and pitching moment coefficients experimentally for the situation where there is not flow through the blowing outlet, called the no blowing condition by means of wind tunnel tests. The methodology to obtain the forces experimentally was through an aerodynamic wire balance. Obtained results were compared with numerical results by means of computational fluid dynamics (CFD) from references and found in very good agreement. Finally, a selection of the airfoil with the best aerodynamic performance is done and proposed for further analysis including the blowing condition.

Modeling and simulation of a spherical mobile robot

Spherical mobile robot (SMR) has been studied analytically and experimentally in this paper, a novel design with an internal propulsion mechanism and mathematical models of the robot's dynamics and kinematics are introduced. A 3D model of robot is built by SOLIDWORKS and then exported to ADAMS2007 for simulation. The results of simulation by combining MATLAB/SIMULINK with ADAMS are presented. It is shown experimentally that the behavior of actual model consist well with the prediction of simulation.

The Chandra X-Ray Observatory: An overview

The Chandra X-Ray Observatory, one of NASA's Great Observatories, was successfully launched on July 23, 1999 by the Space Shuttle Columbia. After release from Columbia, an Inertial Upper Stage was used to further boost the observatory. After five subsequent firings over 15 days of an internal propulsion system, the Observatory was placed in a highly elliptical orbit. The first x-rays focussed by the telescope were observed on August 12, 1999. Despite an initial surprise that the x-ray telescope was far more efficient for concentrating low-energy protons than had been anticipated, the observatory is performing well and is returning superb scientific data. Operating together with other space observatories, most notably the recently activated XMM-Newton, it is clear that with Chandra we are entering a new era of discovery in high-energy astrophysics.

Review—Computational Methods for Internal Flows With Emphasis on Turbomachinery

A review is given of current computational methods for analyzing flows in turbomachinery and other related internal propulsion components. The methods are divided primarily into two classes, inviscid and viscous. The inviscid methods deal specifically with turbomachinery applications. Viscous methods, on the other hand, due to the state-of-the-art, deal with generalized duct flows as well as flows in turbomachinery passages. Inviscid methods are categorized into the potential, stream function, and Euler approaches. Viscous methods are treated in terms of parabolic, partially parabolic, and elliptic procedures.

Analysis of an internal propulsion system: A. W. Farrall.Michigan Agricultural Experimental Station Bulletin. November 1965.

Analysis of an internal propulsion system: A. W. Farrall.Michigan Agricultural Experimental Station Bulletin. November 1965.