Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

NMR Spectrometers: Radiofrequency Pulses and Pulse Sequences

NMR Spectrometers: Radiofrequency Pulses and Pulse Sequences

A pulse is a short burst of radio waves distributed over a range of frequencies that simultaneously excites all the nuclei in the sample. Upon passing a radio frequency pulse along the x-axis, the nuclei absorb energy corresponding to their Larmor frequencies and achieve resonance. This shifts the net magnetization vector from the z-axis toward the transverse plane. This angle of rotation of the magnetization vector, or the flip angle, is proportional to the duration and intensity of the pulse.

Group Polarization

Group Polarization

Group polarization is the strengthening of an original group attitude following the discussion of views within a group (Teger & Pruitt, 1967). That is, if a group initially favors a viewpoint, after discussion the group consensus is likely a stronger endorsement of the viewpoint. Conversely, if the group was initially opposed to a viewpoint, group discussion would likely lead to stronger opposition.

Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)

Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)

Insensitive Nuclei Enhanced by Polarization Transfer (INEPT) is an advanced Nuclear Magnetic Resonance (NMR) technique specifically designed to detect and enhance the signals of low-abundance nuclei, such as carbon-13 and nitrogen-15, in small molecules. The fundamental principle behind INEPT is the transfer of polarization from a more abundant and highly polarizable nucleus, typically hydrogen-1, to the low-abundance nucleus of interest. This process effectively boosts the NMR signal of the...

Atomic Nuclei: Magnetic Resonance

Atomic Nuclei: Magnetic Resonance

The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...

Cell Polarization by Rho Proteins

Cell Polarization by Rho Proteins

Cell polarity is the asymmetric distribution of cellular and membrane components, making one side of the cell different from the other. This polarity is essential to many processes such as embryogenesis, axon migration, glucose transport across epithelial cells, and directional cell migration. A migrating cell responds to intracellular or extracellular signals via molecular cascades that reorganize the actin cytoskeleton to establish this polarity. In these cells, the Rho family proteins Cdc42,...

Dielectric Polarization in a Capacitor

Dielectric Polarization in a Capacitor

The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...

You might also read

Related Articles

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

Sort by

Same author

Discovery of a Novel Lung-Restricted ALK5 Inhibitor for the Treatment of Idiopathic Pulmonary Fibrosis.

Journal of medicinal chemistry·2026

Same author

Design, Synthesis, and Activity of a Novel Series of Pyridazine-Based ALK5 Inhibitors.

ACS medicinal chemistry letters·2024

Same author

Residual Dipolar Coupling Based Conformational Analysis Allows the Configurational Assessment of Steroids with up to Eight Stereocenters.

ChemPlusChem·2023

Same author

Discovery of Clinical Candidate CHF-6366: A Novel Super-soft Dual Pharmacology Muscarinic Antagonist and β<sub>2</sub> Agonist (MABA) for the Inhaled Treatment of Respiratory Diseases.

Journal of medicinal chemistry·2022

Same author

Genomic erosion in a demographically recovered bird species during conservation rescue.

Conservation biology : the journal of the Society for Conservation Biology·2022

Same author

Quantitation of Commercially Available API Solid Forms by Application of the NMR-qSRC Approach: An Optimization Strategy Based on <i>In Silico</i> Simulations.

Analytical chemistry·2021

Search research articles

Related Experiment Video

Updated: Jun 10, 2026

Polarization-Sensitive Two-Photon Microscopy for a Label-Free Amyloid Structural Characterization

Polarization-Sensitive Two-Photon Microscopy for a Label-Free Amyloid Structural Characterization

Published on: September 8, 2023

The Flipped LOngitudinal Polarization sequence.

Luca Venturi¹, Brian Hills

¹Institute of Food Research, Norwich Research Park, Colney, Norwich, UK.

Magnetic Resonance Imaging

|July 22, 2010

Summary

This summary is machine-generated.

Researchers developed Flipped LOngitudinal Polarization (FLOP) to counteract relaxation effects in MRI. This technique periodically restores longitudinal magnetization, enabling faster measurements and improved T(1) mapping.

More Related Videos

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference

Published on: September 5, 2019

Related Experiment Videos

Last Updated: Jun 10, 2026

Polarization-Sensitive Two-Photon Microscopy for a Label-Free Amyloid Structural Characterization

Polarization-Sensitive Two-Photon Microscopy for a Label-Free Amyloid Structural Characterization

Published on: September 8, 2023

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference

Published on: September 5, 2019

Area of Science:

Magnetic Resonance Imaging (MRI)
Biophysics

Background:

Relaxation processes, specifically T(1) relaxation, limit signal recovery in MRI.
Longitudinal magnetization attenuation reduces image quality and measurement speed.

Purpose of the Study:

To introduce a novel pulse sequence, Flipped LOngitudinal Polarization (FLOP), to mitigate relaxation effects.
To demonstrate the utility of FLOP for efficient MRI measurements.

Main Methods:

Implementation of a pulse sequence involving 180-degree pulses to flip longitudinal magnetization.
Integration of the FLOP sequence into existing MRI protocols.

Main Results:

FLOP effectively restores longitudinal magnetization, counteracting relaxation-induced signal decay.
Demonstrated successful application for fast, single-shot T(1) relaxation time measurements.
Validated FLOP for three-dimensional T(1) mapping.

Conclusions:

FLOP offers a method to periodically recover longitudinal magnetization, overcoming relaxation limitations.
The technique enhances efficiency for T(1) measurements and 3D mapping in MRI.