Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Generation of Straight or Branched Actin Filaments01:14

Generation of Straight or Branched Actin Filaments

3.7K
The straight or branched structure formation of actin filaments is controlled by nucleating proteins such as the formins and Arp2/3 complex. Formin-mediated assembly results in straight filaments, whereas Arp2/3 protein complex-mediated assembly results in branched actin filaments.
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
3.7K
Mechanism of Filopodia Formation01:39

Mechanism of Filopodia Formation

3.1K
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
3.1K
Force On A Current Loop In A Magnetic Field01:17

Force On A Current Loop In A Magnetic Field

4.0K
Magnetic forces on wires carrying current are most frequently applied in motors. A DC motor is a device that converts electrical energy into mechanical work. In motors, wire loops are enclosed in a magnetic field. When current flows through the loops, the magnetic field applies torque, which causes the shaft to rotate. The direction of the current is reversed once the loop's surface area is lined up with the magnetic field, causing a constant torque on the loop. During the process, commutators...
4.0K
Magnetic Force On Current-Carrying Wires: Example01:22

Magnetic Force On Current-Carrying Wires: Example

2.1K
In a magnetic field, moving charges encounter a force. If a wire contains these moving charges, i.e., if the wire is carrying a current, then a force acts on the wire as well. Consider a pair of flexible leads holding a wire that is 40 cm long and 10 g in weight in a horizontal position. The wire is placed in a constant magnetic field of 0.40 T, as shown in Figure 1(a). Determine the magnitude and direction of the current flowing in the wire needed to remove the tension in the supporting leads.
2.1K
Actin Filament Depolymerization01:19

Actin Filament Depolymerization

3.8K
Actin filaments (F-actin) are composed of actin subunits. The dissociation of actin monomers can occur from either end of F-actin. The rate of dissociation is faster from the minus-end or the pointed end, where the actin subunits exist with a bound ADP, together known as ADP-actin. The depolymerization of F-actin is aided by proteins, including the actin-depolymerizing factor (ADF) and cofilin family of proteins, gelsolin, and glia maturation factor (GMF).
In F-actin, the ADF/cofilin proteins...
3.8K
Disassembly of Intermediate Filaments01:35

Disassembly of Intermediate Filaments

2.6K
Intermediate filaments (IFs) do not undergo spontaneous disassembly. Enzymes, kinases, and phosphatases add and remove phosphates from specific sites to regulate their disassembly. The IF concentration in the cytoplasm also regulates the disassembly. If the concentration crosses a threshold, it activates the protein kinases in the vicinity, allowing the phosphorylation of IFs.
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
2.6K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Helical opto-thermoviscous flows drive out-of-plane rotation and particle spinning in a highly viscous micro-environment.

Light, science & applications·2026
Same author

Rotation reversal of chiral bacterial vortices.

Soft matter·2025
Same author

Modal analysis and optimization of swimming active filaments.

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences·2025
Same author

Optical Micromanipulations Based on Model Predictive Control of Thermoviscous Flows.

Small (Weinheim an der Bergstrasse, Germany)·2025
Same author

Axisymmetric thermoviscous and thermal expansion flows for microfluidics.

Journal of engineering mathematics·2025
Same author

Designing optimal elastic filaments for viscous propulsion.

Soft matter·2025
Same journal

Inverse FIP effect plasma in the solar atmosphere: a synthesis of current understanding and new insights from AR 11967.

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences·2026
Same journal

Signs of sulfur fractionation under high magnetic field strength.

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences·2026
Same journal

First ionization potential fractionation of sulfur observed with spectral imaging of the coronal environment.

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences·2026
Same journal

Chromospheric dynamics and turbulence regulate the solar FIP effect.

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences·2026
Same journal

Exploring the link between wave activity in the photospheric velocity driver and the FIP bias in the solar corona.

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences·2026
Same journal

Radiative hydrodynamic simulations of first ionization potential fractionation in solar flares.

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences·2026
See all related articles

Related Experiment Video

Updated: Jan 18, 2026

Directly Measuring Forces Within Reconstituted Active Microtubule Bundles
07:47

Directly Measuring Forces Within Reconstituted Active Microtubule Bundles

Published on: May 10, 2022

1.9K

Load-dependent resistive-force theory for helical filaments.

Pyae Hein Htet1, Eric Lauga1

  • 1Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK.

Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
|September 11, 2025
PubMed
Summary
This summary is machine-generated.

The optimal resistance coefficients for helical microswimmers are load-dependent, contrary to previous assumptions. This finding impacts models of bacteria and artificial swimmers navigating at low Reynolds numbers.

Keywords:
flagellumhelixmicroswimmerresistive-force theory

More Related Videos

Analyses of Actin Dynamics, Clutch Coupling and Traction Force for Growth Cone Advance
07:53

Analyses of Actin Dynamics, Clutch Coupling and Traction Force for Growth Cone Advance

Published on: October 21, 2021

3.9K
Demonstrating the Uses of the Novel Gravitational Force Spectrometer to Stretch and Measure Fibrous Proteins
13:51

Demonstrating the Uses of the Novel Gravitational Force Spectrometer to Stretch and Measure Fibrous Proteins

Published on: March 19, 2011

10.7K

Related Experiment Videos

Last Updated: Jan 18, 2026

Directly Measuring Forces Within Reconstituted Active Microtubule Bundles
07:47

Directly Measuring Forces Within Reconstituted Active Microtubule Bundles

Published on: May 10, 2022

1.9K
Analyses of Actin Dynamics, Clutch Coupling and Traction Force for Growth Cone Advance
07:53

Analyses of Actin Dynamics, Clutch Coupling and Traction Force for Growth Cone Advance

Published on: October 21, 2021

3.9K
Demonstrating the Uses of the Novel Gravitational Force Spectrometer to Stretch and Measure Fibrous Proteins
13:51

Demonstrating the Uses of the Novel Gravitational Force Spectrometer to Stretch and Measure Fibrous Proteins

Published on: March 19, 2011

10.7K

Area of Science:

  • Fluid dynamics
  • Biophysics
  • Microscale transport

Background:

  • Flagellated bacteria and artificial microswimmers use helical filament rotation for propulsion at low Reynolds numbers.
  • Lighthill's 1976 work established 'optimal' resistance coefficients for force-free helical swimming without a load.
  • These coefficients are widely used but may be inaccurate under different conditions.

Purpose of the Study:

  • To investigate the impact of attached loads on the resistance coefficients of rotating helical filaments.
  • To re-evaluate the applicability of Lighthill's coefficients when a load is present.
  • To provide a physical explanation for load-dependent resistance.

Main Methods:

  • Revisiting resistive-force theory for rotating helical filaments with attached loads.
  • Quantifying the deviation of calculated coefficients from Lighthill's values based on load size.
  • Developing a physical model to explain the observed load-dependence.

Main Results:

  • The 'optimal' resistance coefficients are dependent on the size of the attached load.
  • Lighthill's coefficients become increasingly inaccurate as the load size increases.
  • A physical explanation for the load-dependence of resistance coefficients was identified.

Conclusions:

  • Previous assumptions about load-independent resistance coefficients for helical swimmers are challenged.
  • Accurate modeling of microswimmer propulsion requires considering the load size.
  • This research refines our understanding of fluid dynamics at the microscale.