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

Position of Equilibrium in Acid-Base Reactions02:05

Position of Equilibrium in Acid-Base Reactions

14.7K
In any solution, the value of pKa indicates whether an acid is completely dissociated or not. A negative pKa corresponds to a stronger acid, whereas a positive pKa corresponds to a weaker acid. Consider the reaction between ammonia and an ethoxide ion. In this reaction, ethanol with a pKa of 15.9 is a stronger acid than ammonia with a pKa of 38. Recall that the strong acid forms a weak conjugate base, and a weak acid forms a strong conjugate base. Hence, the ethoxide ion is a weak base.
14.7K
Position-effect Variegation02:32

Position-effect Variegation

7.0K
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
7.0K
Magnetic Susceptibility and Permeability01:31

Magnetic Susceptibility and Permeability

2.3K
In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
2.3K
Phase Contrast and Differential Interference Contrast Microscopy01:26

Phase Contrast and Differential Interference Contrast Microscopy

12.8K
Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
12.8K
Susceptibility, Permittivity and Dielectric Constant01:26

Susceptibility, Permittivity and Dielectric Constant

2.8K
When placed in an external electric field, a dielectric material gets polarized. The charge density in the dielectric material is given by the sum of the bound and free charge densities, while the total charge density can also be written in terms of the total electric field. The bound charge density can be measured in terms of polarization, leading to the relationship between electric displacement and polarization.
2.8K
Serial Position Effect01:03

Serial Position Effect

539
The serial position effect is a cognitive phenomenon where individuals are more likely to recall the first and last items in a list compared to those in the middle. This effect is divided into the primacy effect and the recency effect. The primacy effect is observed when the initial items in a list are remembered better. This occurs because these items are rehearsed more frequently or receive more elaborative processing, allowing them to be encoded into long-term memory more effectively. For...
539

You might also read

Related Articles

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

Sort by
Same author

Accelerated susceptibility-driven positive contrast MRI reconstruction based on primal-dual optimization with minimal parameter tuning.

Quantitative imaging in medicine and surgery·2026
Same author

Novel Metal-Free Nanozyme for Targeted Imaging and Inhibition of Atherosclerosis via Macrophage Autophagy Activation to Prevent Vulnerable Plaque Formation and Rupture.

ACS applied materials & interfaces·2024
Same author

The MYB transcription factor PpMYB5 regulates Pp4CL1/Pp4CL2 expression to promote lignin biosynthesis of fruit russeting in the flat nectarine.

Plant cell reports·2024
Same author

The Effect of Placebo on Pruritus in Patients with Chronic Urticaria: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials.

Clinical drug investigation·2024
Same author

Direct abdominal vein thrombus imaging (DATI): a contrast-free black-blood MR technique for the diagnosis of abdominal vein thrombosis.

Abdominal radiology (New York)·2024
Same author

High efficiency free-breathing 3D thoracic aorta vessel wall imaging using self-gating image reconstruction.

Magnetic resonance imaging·2024

Related Experiment Video

Updated: Jan 25, 2026

Troubleshooting FoCUS Image Acquisition: Patient Positioning, Transducer Manipulation, and Image Optimization
06:50

Troubleshooting FoCUS Image Acquisition: Patient Positioning, Transducer Manipulation, and Image Optimization

Published on: March 3, 2023

2.2K

Positive-contrast susceptibility imaging based on first-order primal-dual optimization.

Caiyun Shi1,2, Jing Cheng1,2, Guoxi Xie3

  • 1Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen, Guangdong, China.

Magnetic Resonance in Medicine
|May 9, 2019
PubMed
Summary

A new primal-dual (PD) formulation improves positive-contrast MRI reconstruction for metallic devices. This method offers faster imaging and enhanced accuracy compared to existing techniques.

Keywords:
Chambolle-Pockinterventional devicespositive contrast imagingprimal-dualsusceptibility

More Related Videos

Contrast Enhanced Vessel Imaging using MicroCT
05:50

Contrast Enhanced Vessel Imaging using MicroCT

Published on: January 27, 2011

13.1K
Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice
08:05

Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice

Published on: June 29, 2022

3.4K

Related Experiment Videos

Last Updated: Jan 25, 2026

Troubleshooting FoCUS Image Acquisition: Patient Positioning, Transducer Manipulation, and Image Optimization
06:50

Troubleshooting FoCUS Image Acquisition: Patient Positioning, Transducer Manipulation, and Image Optimization

Published on: March 3, 2023

2.2K
Contrast Enhanced Vessel Imaging using MicroCT
05:50

Contrast Enhanced Vessel Imaging using MicroCT

Published on: January 27, 2011

13.1K
Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice
08:05

Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice

Published on: June 29, 2022

3.4K

Area of Science:

  • Medical Imaging
  • Magnetic Resonance Imaging (MRI)
  • Computational Imaging

Background:

  • Metallic interventional devices pose challenges for MRI due to susceptibility effects.
  • Accurate imaging of these devices is crucial for monitoring and treatment planning.

Purpose of the Study:

  • To develop a faster and higher-quality positive-contrast MRI reconstruction method.
  • To improve susceptibility mapping for visualizing metallic implants.

Main Methods:

  • A primal-dual (PD) formulation was incorporated into a susceptibility-based positive-contrast MRI technique.
  • A kernel deconvolution algorithm with regularized L1 minimization was used to estimate susceptibility distributions.
  • The PD algorithm's performance was compared to other iterative methods using simulations and phantom experiments.

Main Results:

  • The PD approach demonstrated significantly faster reconstruction times than other tested algorithms.
  • Comparable or superior visualization and accuracy of metallic devices were achieved with the PD method.
  • The PD algorithm performed well across various signal-to-noise ratios (SNRs) and orientations to the B0 field.

Conclusions:

  • The proposed susceptibility-based positive-contrast imaging technique utilizing a PD algorithm is effective.
  • The PD approach offers superior performance in terms of reconstruction speed and accuracy for imaging metallic interventional devices.