Tethered stick insect walking: A modified slippery surface setup with optomotor stimulation and electrical monitoring of tarsal contact

On a slippery surface the forelegs of a decapitated stick insect walk forwards and the hindlegs, backwards. Animals with only forelegs but that are otherwise intact walk forwards, whereas animals with only hindlegs walk mostly backwards. Usually when intact animals start to walk, their hindlegs exert a rearwards thrust on the substrate, but occasionally the starting forces are directed forwards. A rampwise extension of the femoral chordotonal organ in the fixed foreleg of a walking animal first excites the flexor tibiae muscle (positive feedback). Towards the end of the ramp stimulus the activity of the flexor decreases, and the extensor tibiae motor neurones become strongly active. All experiments indicated that the inherent direction of movement of the metathorax is rearwards. In intact animals there must be a coordinating pathway from the prothorax to the metathorax that, together with the suboesophageal ganglion, induces the hindlegs to walk forwards.

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Control of Stepping Velocity in the Stick Insect Carausius morosus

Journal of Neurophysiology ◽

10.1152/jn.00257.2009 ◽

2009 ◽

Vol 102 (2) ◽

pp. 1180-1192 ◽

Cited By ~ 16

Author(s):

Matthias Gruhn ◽

Géraldine von Uckermann ◽

Sandra Westmark ◽

Anne Wosnitza ◽

Ansgar Büschges ◽

...

Keyword(s):

Motor Neurons ◽

Walking Speed ◽

Stick Insect ◽

Behavioral Experiments ◽

General Increase ◽

Carausius Morosus ◽

Mechanical Coupling ◽

Stick Insects ◽

Motoneuron Activity ◽

Slippery Surface

We performed electrophysiological and behavioral experiments in single-leg preparations and intact animals of the stick insect Carausius morosus to understand mechanisms underlying the control of walking speed. At the level of the single leg, we found no significant correlation between stepping velocity and spike frequency of motor neurons (MNs) other than the previously shown modification in flexor (stance) MN activity. However, pauses between stance and swing motoneuron activity at the transition from stance to swing phase and stepping velocity are correlated. Pauses become shorter with increasing speed and completely disappear during fast stepping sequences. By means of extra- and intracellular recordings in single-leg stick insect preparations we found no systematic relationship between the velocity of a stepping front leg and the motoneuronal activity in the ipsi- or contralateral mesothoracic protractor and retractor, as well as flexor and extensor MNs. The observations on the lack of coordination of stepping velocity between legs in single-leg preparations were confirmed in behavioral experiments with intact stick insects tethered above a slippery surface, thereby effectively removing mechanical coupling through the ground. In this situation, there were again no systematic correlations between the stepping velocities of different legs, despite the finding that an increase in stepping velocity in a single front leg is correlated with a general increase in nerve activity in all connectives between the subesophageal and all thoracic ganglia. However, when the tethered animal increased walking speed due to a short tactile stimulus, provoking an escape-like response, stepping velocities of ipsilateral legs were found to be correlated for several steps. These results indicate that there is no permanent coordination of stepping velocities between legs, but that such coordination can be activated under certain circumstances.

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Faculty Opinions recommendation of Stick insect genomes reveal natural selection's role in parallel speciation.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718389085.793496432 ◽

2014 ◽

Author(s):

Ian Wang

Keyword(s):

Stick Insect

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A numerical frame work of magnetically driven Powell-Eyring nanofluid using single phase model

Scientific Reports ◽

10.1038/s41598-021-96040-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wasim Jamshed ◽

Mohamed R. Eid ◽

Kottakkaran Sooppy Nisar ◽

Nor Ain Azeany Mohd Nasir ◽

Abhilash Edacherian ◽

...

Keyword(s):

Differential Equations ◽

Numerical Solutions ◽

Volume Fraction ◽

Dissipative Flow ◽

Uniform Medium ◽

Heat Transport Properties ◽

Flow Heat ◽

Frame Work ◽

Slippery Surface ◽

Nanoparticle Shapes

AbstractThe current investigation aims to examine heat transfer as well as entropy generation analysis of Powell-Eyring nanofluid moving over a linearly expandable non-uniform medium. The nanofluid is investigated in terms of heat transport properties subjected to a convectively heated slippery surface. The effect of a magnetic field, porous medium, radiative flux, nanoparticle shapes, viscous dissipative flow, heat source, and Joule heating are also included in this analysis. The modeled equations regarding flow phenomenon are presented in the form of partial-differential equations (PDEs). Keller-box technique is utilized to detect the numerical solutions of modeled equations transformed into ordinary-differential equations (ODEs) via suitable similarity conversions. Two different nanofluids, Copper-methanol (Cu-MeOH) as well as Graphene oxide-methanol (GO-MeOH) have been taken for our study. Substantial results in terms of sundry variables against heat, frictional force, Nusselt number, and entropy production are elaborate graphically. This work’s noteworthy conclusion is that the thermal conductivity in Powell-Eyring phenomena steadily increases in contrast to classical liquid. The system’s entropy escalates in the case of volume fraction of nanoparticles, material parameters, and thermal radiation. The shape factor is more significant and it has a very clear effect on entropy rate in the case of GO-MeOH nanofluid than Cu-MeOH nanofluid.

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A mechanically robust slippery surface with ‘corn-like’ structures fabricated by in-situ growth of TiO2 on attapulgite

Chemical Engineering Journal ◽

10.1016/j.cej.2021.128953 ◽

2021 ◽

Vol 415 ◽

pp. 128953

Author(s):

Sicheng Yuan ◽

Jianwen Peng ◽

Xiguang Zhang ◽

Dan Lin ◽

Haolei Geng ◽

...

Keyword(s):

In Situ Growth ◽

Slippery Surface

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Outbreak of the stick insect, Ramulus mikado (Phasmatodea, Phasmatidae), in the Akashina area of Japan (Azumino City, Nagano Prefecture)

Entomological Science ◽

10.1111/ens.12467 ◽

2021 ◽

Vol 24 (2) ◽

pp. 196-200

Author(s):

Koki Yano ◽

Takahisa Ozaki ◽

Tomoya Suzuki ◽

Haruka Yamazaki ◽

Masayoshi Nasuno ◽

...

Keyword(s):

Stick Insect ◽

Nagano Prefecture

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Numerical Simulation of Heat Transfer Flow Subject to MHD of Williamson Nanofluid with Thermal Radiation

Symmetry ◽

10.3390/sym13010010 ◽

2020 ◽

Vol 13 (1) ◽

pp. 10

Author(s):

Muhammad Amer Qureshi

Keyword(s):

Heat Transfer ◽

Differential Equations ◽

Thermal Radiation ◽

Single Phase ◽

Physical Parameters ◽

Fundamental Symmetry ◽

Box Scheme ◽

Mhd Boundary Layer ◽

Slippery Surface ◽

Transfer Flow

In this paper, heat transfer and entropy of steady Williamson nanofluid flow based on the fundamental symmetry is studied. The fluid is positioned over a stretched flat surface moving non-uniformly. Nanofluid is analyzed for its flow and thermal transport properties by consigning it to a convectively heated slippery surface. Thermal conductivity is assumed to be varied with temperature impacted by thermal radiation along with axisymmetric magnetohydrodynamics (MHD). Boundary layer approximations lead to partial differential equations, which are transformed into ordinary differential equations in light of a single phase model accounting for Cu-water and TiO2-water nanofluids. The resulting ODEs are solved via a finite difference based Keller box scheme. Various formidable physical parameters affecting fluid movement, difference in temperature, system entropy, skin friction and Nusselt number around the boundary are presented graphically and numerically discussed. It has also been observed that the nanofluid based on Cu-water is identified as a superior thermal conductor rather than TiO2-water based nanofluid.

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