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

¹H NMR Chemical Shift Equivalence: Homotopic and Heterotopic Protons01:03

¹H NMR Chemical Shift Equivalence: Homotopic and Heterotopic Protons

2.8K
Protons in identical electronic environments within a molecule are chemically equivalent and have the same chemical shift. The replacement test is a useful tool to identify chemical equivalence and predict NMR spectra. A substituent replaces each of the protons being examined and the resulting molecules are compared. If the same molecule is obtained, the protons are equivalent or homotopic. Replacement of any hydrogens in ethane by chlorine yields chloroethane because all six protons are...
2.8K
Fischer Projections02:18

Fischer Projections

14.6K
Learning to draw Fischer projections of molecules and understanding their relevance plays a crucial role in the visual depiction of organic molecules. A Fischer projection is a two-dimensional projection on a planar surface to simplify the three-dimensional wedge–dash representation of molecules. This is especially helpful in the case of molecules with multiple chiral centers that can be difficult to draw. Here, all the bonds of interest are represented as horizontal or vertical lines.
14.6K
IR Frequency Region: Fingerprint Region01:03

IR Frequency Region: Fingerprint Region

1.4K
IR spectra are divided into two main regions: the diagnostic region and the fingerprint region. The diagnostic region of the spectrum lies above 1500 cm−1. The absorptions resulting from single-bond vibrations of the N–H, C–H, and O–H stretch at higher wavenumbers and appear on the left side of the spectrum. The stretching absorptions of the C≡C and C≡N occur between 2100–2300 cm−1. In contrast, those arising from stretching absorptions of the...
1.4K
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)01:19

2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)

1.0K
Heteronuclear single-quantum correlation spectroscopy (HSQC) is a 2D NMR technique that reveals one-bond correlations between hydrogen and a heteronucleus. The HSQC experiment is similar to the heteronuclear correlation experiment (HETCOR) but is more sensitive. In the HSQC spectrum, the proton chemical shift is plotted on the horizontal F2 axis, while the 13C chemical shift is plotted on the vertical F1 axis. The corresponding proton and 13C spectra are also shown. The HSQC contour plot does...
1.0K
High-Resolution Mass Spectrometry (HRMS)01:15

High-Resolution Mass Spectrometry (HRMS)

1.8K
The resolution of a mass spectrometer depends on the efficiency of separating ions with different ion masses. The mass of an atom is approximated to the sum of the masses of protons and neutrons inside, considering the masses of protons and neutrons as equal. However, the masses of the proton (1.6726 × 10−24 g) and neutron (1.6749 × 10−24 g) are not truly equal. There is a minor error in the expression of atomic masses relative to the simplest atom of hydrogen. For...
1.8K
2D NMR: Overview of Heteronuclear Correlation Techniques01:18

2D NMR: Overview of Heteronuclear Correlation Techniques

374
Heteronuclear correlation spectroscopy is an analytical technique that investigates the coupling between different types of nuclei, often a proton and an X-nucleus, such as carbon-13 or nitrogen-15. This method is commonly used in nuclear magnetic resonance (NMR) spectroscopy to gain insights into complex chemical compounds' structural and compositional aspects. A typical heteronuclear correlation spectrum displays X-nucleus chemical shifts on one axis and a proton spectrum on the other...
374

You might also read

Related Articles

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

Sort by
Same author

Impact of enhanced recovery after surgery (ERAS) protocols on clinical outcomes of patients undergoing anterior cervical discectomy and fusion: A retrospective study.

Medicine·2026
Same author

Correction: Zinc oxide nanoparticle chelated phosphocreatine-grafted chitosan composite hydrogels for enhancing osteogenesis and angiogenesis in bone regeneration.

Frontiers in medicine·2026
Same author

Correction: P2X7 Receptor Suppression Preserves Blood-Brain Barrier through Inhibiting RhoA Activation after Experimental Intracerebral Hemorrhage in Rats.

Scientific reports·2026
Same author

Association between age-adjusted visceral fat index (AVAI) and congestive heart failure: A cross-sectional study.

Science progress·2026
Same author

A Needlelike Nano-hydroxyapatite-Based Hydrogel Accelerates Critical Bone Defect Regeneration via Osteo-/Angiogenesis and Osteoimmune Regulation.

Biomaterials research·2026
Same author

Corrigendum to "Dose sarcopenia affect the clinical outcomes of elder patients treated with posterior cervical laminoplasty? A retrospective cohort study". [Curr Problem Surg. 2026;74:101932].

Current problems in surgery·2026

Related Experiment Video

Updated: Oct 17, 2025

Lumped-Parameter and Finite Element Modeling of Heart Failure with Preserved Ejection Fraction
09:20

Lumped-Parameter and Finite Element Modeling of Heart Failure with Preserved Ejection Fraction

Published on: February 13, 2021

6.7K

Similarities and Differences Between HFmrEF and HFpEF.

Peixin Li1,2,3, Hengli Zhao1,2,3,4, Jianyu Zhang5

  • 1State Key Laboratory of Organ Failure Research, Department of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, China.

Frontiers in Cardiovascular Medicine
|October 7, 2021
PubMed
Summary
This summary is machine-generated.

New heart failure (HF) guidelines define HF with mid-range EF (HFmrEF) as distinct. Research suggests HFmrEF patients may benefit from reduced EF (HFrEF) treatments, though HFmrEF and HF with preserved EF (HFpEF) share some characteristics.

Keywords:
cardiac abnormalityheart failureheart failure with mid-range ejection fractionheart failure with preserved ejection fractionheterogeneity

More Related Videos

Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
10:01

Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase

Published on: December 4, 2017

12.4K
Author Spotlight: Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon
07:22

Author Spotlight: Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon

Published on: February 3, 2023

6.9K

Related Experiment Videos

Last Updated: Oct 17, 2025

Lumped-Parameter and Finite Element Modeling of Heart Failure with Preserved Ejection Fraction
09:20

Lumped-Parameter and Finite Element Modeling of Heart Failure with Preserved Ejection Fraction

Published on: February 13, 2021

6.7K
Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
10:01

Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase

Published on: December 4, 2017

12.4K
Author Spotlight: Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon
07:22

Author Spotlight: Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon

Published on: February 3, 2023

6.9K

Area of Science:

  • Cardiology
  • Heart Failure Research
  • Clinical Phenotyping

Background:

  • Current heart failure (HF) classification includes HF with reduced EF (HFrEF), HF with mid-range EF (HFmrEF), and HF with preserved EF (HFpEF).
  • HFmrEF, defined by left ventricular ejection fraction (EF) of 40-49%, is recognized as a unique phenotype, prompting further investigation.
  • HFmrEF patients exhibit characteristics intermediate between HFrEF and HFpEF, with similarities in etiology to HFrEF and prognosis to HFpEF.

Purpose of the Study:

  • To review current understanding of HFmrEF and HFpEF, focusing on their epidemiology, etiology, clinical indicators, and pathophysiology.
  • To explore potential treatment strategies for HFmrEF, particularly the efficacy of HFrEF-focused therapies.
  • To discuss the heterogeneity within HFmrEF and HFpEF and its impact on disease prognosis and management.

Main Methods:

  • Review of current clinical practice data.
  • Analysis of mechanistic studies.
  • Examination of observational studies and post-hoc analyses of randomized controlled trials.

Main Results:

  • HFmrEF patients share etiological factors with HFrEF but have a prognosis and quality of life closer to HFpEF.
  • Growing evidence suggests HFmrEF and HFpEF exhibit significant heterogeneity in presentation and pathophysiology.
  • Preliminary data indicate potential benefits of HFrEF treatment strategies (e.g., beta-blockers, ACE inhibitors, ARBs, MRAs, sacubitril/valsartan) for HFmrEF patients.

Conclusions:

  • HFmrEF represents a distinct clinical entity requiring further research into its specific mechanisms and optimal treatment.
  • Understanding the heterogeneity of HFmrEF and HFpEF is crucial for tailoring effective therapeutic approaches.
  • HFrEF treatment paradigms may offer a beneficial therapeutic avenue for patients with HFmrEF, warranting further investigation.