The VA/DoD Chronic Effects of Neurotrauma Consortium: An Overview at Year 1

David X Cifu1, Ramon Diaz-Arrastia1, Rick L Williams1

  • 1is the senior traumatic brain injury specialist within the U.S. Department of Veterans Affairs. is a clinical psychologist at Hunter Holmes McGuire VAMC in Richmond, Virginia. is director of clinical research, Center for Neuroscience and Regenerative Medicine and professor of neurology at the Uniformed Services University of the Health Sciences in Bethesda, Maryland. is the principal scientist at RTI International in Raleigh, North Carolina. Dr. Carne is an associate professor, is an associate professor, is director of finance, is an assistant professor, and Dr. Cifu is the chairman and the Herman J. Flax Professor, all in the Department of Physical Medicine and Rehabilitation at Virginia Commonwealth University in Richmond.

Related Concept Videos

Effects of Chemicals: Overview01:27

Effects of Chemicals: Overview

Drugs, encompassing various chemical compounds from natural sources, lab synthesis, or genetic engineering, elicit different biological responses in living organisms. Some of these responses are desirable or therapeutic, while others are undesirable. The primary goal of administering a drug is to achieve a therapeutic effect, that is, to address a specific disease or health condition. Any concurrent effects outside of this therapeutic outcome are considered undesirable. These undesirable...
2.2K
Inductive Effects on Chemical Shift: Overview01:27

Inductive Effects on Chemical Shift: Overview

The protons in unsubstituted alkanes are strongly shielded with chemical shifts below 1.8 ppm. Methine, methylene, and methyl protons appear at approximately 1.7, 1.2 and 0.7 ppm, while the proton signal from methane appears at 0.23 ppm. An electronegative substituent, such as chlorine, withdraws the electron density from the protons, increasing their chemical shift. Progressive substitution of the hydrogens in methane by chlorine shifts the proton signals increasingly downfield, to 3.05 ppm in...
2.2K
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview01:07

Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview

In the presence of an aqueous base and a halogen, primary amides can lose the carbonyl (as carbon dioxide) and undergo rearrangement to form primary amines. This reaction, called the Hofmann rearrangement, can produce primary amines (aryl and alkyl) in high yields without contamination by secondary and tertiary amines.
3.7K
π Electron Effects on Chemical Shift: Overview01:27

π Electron Effects on Chemical Shift: Overview

An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...
1.7K
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview01:26

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview

Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...
3.9K
Buffer Effectiveness02:19

Buffer Effectiveness

Buffer solutions do not have an unlimited capacity to keep the pH relatively constant . Instead, the ability of a buffer solution to resist changes in pH relies on the presence of appreciable amounts of its conjugate weak acid-base pair. When enough strong acid or base is added to substantially lower the concentration of either member of the buffer pair, the buffering action within the solution is compromised.
The buffer capacity is the amount of acid or base that can be added to a given volume...
55.1K