Predictive value of traction force measurement in vacuum extraction: Development of a multivariate prognostic model

SUMMARYPipeline grids of various size and material are pervasive in today's modern society. The frequent inspection and maintenance of such pipeline grids have presented a tremendous challenge. It is advocated that only advanced robot design embedded with intelligent electronics and control algorithms could perform the job. Given the ever increasing demands for intelligent in-pipe robots, various in-pipe drive mechanisms have been reported. One of the simplest is helical wheel drives that have only one degree of freedom. All previously reported in-pipe helical drives are based on independent passive wheels that are tilted an angle. One of the major problems of current helical wheel drives is their unstable traction force. In this paper, instead of allowing the wheels to rotate independently, they are synchronized by adding a timing belt. This small change will result in significant improvement which will be highlighted in this paper. In the proposed driving method, tracking force is analyzed together with a comprehensive set of traction force measurement experiments. Both analysis and experiments have shown that the proposed mechanism has great potential for in-pipe robot drive design.

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Single cell micro-pillar-based characterization of endothelial and fibroblast cell mechanics

10.1101/2021.10.11.463878 ◽

2021 ◽

Author(s):

Julia Eckert ◽

Yasmine Abouleila ◽

Thomas Schmidt ◽

Alireza Mashaghi

Keyword(s):

Single Cell ◽

Force Measurement ◽

Traction Force ◽

Fibroblast Cell ◽

Cell Types ◽

Fibroblast Cells ◽

Cellular Processes ◽

Sense And Respond ◽

Underlying Mechanisms

Mechanotransduction, the ability of cells to sense and respond to the mechanical cues from their microenvironment, plays an important role in numerous cellular processes, ranging from cell migration to differentiation. Several techniques have been developed to investigate the underlying mechanisms of mechanotransduction, in particular, force measurement-based techniques. However, we still lack basic single cell quantitative comparison on the mechanical properties of commonly used cell types, such as endothelial and fibroblast cells. Such information is critical to provide a precedent for studying complex tissues and organs that consist of various cell types. In this short communication, we report on the mechanical characterization of the commonly used endothelial and fibroblast cells at the single cell level. Using a micropillar-based assay, we measured the traction force profiles of these cells. Our study showcases differences between the two cell types in their traction force distribution and morphology. The results reported can be used as a reference and to lay the groundwork for future analysis of numerous disease models involving these cells.

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Traction force during vacuum extraction: a prospective observational study

BJOG An International Journal of Obstetrics & Gynaecology ◽

10.1111/1471-0528.13222 ◽

2015 ◽

Vol 122 (13) ◽

pp. 1809-1816 ◽

Cited By ~ 13

Author(s):

K Pettersson ◽

J Ajne ◽

K Yousaf ◽

D Sturm ◽

M Westgren ◽

...

Keyword(s):

Observational Study ◽

Prospective Observational Study ◽

Traction Force ◽

Vacuum Extraction

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Force Measurement Determines the Dierection of Cell Migration by the Traction Force Microscopy

Biophysical Journal ◽

10.1016/j.bpj.2020.11.628 ◽

2021 ◽

Vol 120 (3) ◽

pp. 66a-67a

Author(s):

Takeshi Sakamoto ◽

Yuwen Mei ◽

Justin J. Raupp

Keyword(s):

Cell Migration ◽

Force Measurement ◽

Traction Force ◽

Traction Force Microscopy ◽

Force Microscopy

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A 3D Cell Traction Force Measurement Technique Based on Collagen Fiber Tracking

Biophysical Journal ◽

10.1016/j.bpj.2008.12.2693 ◽

2009 ◽

Vol 96 (3) ◽

pp. 522a-523a

Author(s):

David A. Vader ◽

Thomas S. Deisboeck ◽

David A. Weitz

Keyword(s):

Measurement Technique ◽

Collagen Fiber ◽

Force Measurement ◽

Traction Force ◽

Fiber Tracking ◽

Cell Traction

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Quantifying cell-generated forces: Poisson’s ratio matters

Communications Physics ◽

10.1038/s42005-021-00740-y ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yousef Javanmardi ◽

Huw Colin-York ◽

Nicolas Szita ◽

Marco Fritzsche ◽

Emad Moeendarbary

Keyword(s):

Poisson’S Ratio ◽

Cell Activation ◽

Immune Cell ◽

Force Measurement ◽

Traction Force ◽

Cellular Systems ◽

Poisson's Ratio ◽

Basic Material ◽

Biological Phenomena ◽

Force Reconstruction

AbstractQuantifying mechanical forces generated by cellular systems has led to key insights into a broad range of biological phenomena from cell adhesion to immune cell activation. Traction force microscopy (TFM), the most widely employed force measurement methodology, fundamentally relies on knowledge of the force-displacement relationship and mechanical properties of the substrate. Together with the elastic modulus, the Poisson’s ratio is a basic material property that to date has largely been overlooked in TFM. Here, we evaluate the sensitivity of TFM to Poisson’s ratio by employing a series of computer simulations and experimental data analysis. We demonstrate how applying the correct Poisson’s ratio is important for accurate force reconstruction and develop a framework for the determination of error levels resulting from the misestimation of the Poisson’s ratio. In addition, we provide experimental estimation of the Poisson’s ratios of elastic substrates commonly applied in TFM. Our work thus highlights the role of Poisson’s ratio underpinning cellular force quantification studied across many biological systems.

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