Commodities are raw materials intended for use or consumption. There are three main commodity classifications: Agriculture commodities (often referred to as soft commodities), energy commodities, and metal commodities (referred to as hard commodities). The most commonly traded commodities are crude oil, gold, silver, and copper. Commodity markets can include physical delivery, referred to as a spot contract. Most trades, however, are carried out through derivative trading using futures, forwards, CFD's, and options.
Donna Perrin, RGN, is practice development sister, A&E, Frimley Park Hospital, Surrey. Fluid resuscitation is one of the most important aspects of the acute medical management of critically ill patients.
Reverberation artifact is a common ultrasound artifact and occurs when a sound pulse reverberates back and forth between two strong parallel reflectors.With the exception of comet-tail artifact, a subtype of reverberation, reverberation artefact has little diagnostic use.: Reverberation artifact occurs when an ultrasound pulse gets trapped between two strong parallel reflectors.