A technique for analysis of the chemical composition of molecules. A substance is bombarded with monochromatic ELECTRONS. Some of the electrons passing through the specimen will lose energy when they ionize inner shell electrons of the atoms in the specimen. The energy loss is element dependent. Analysis of the energy loss spectrum reveals the elemental composition of a specimen. ENERGY-FILTERED TRANSMISSION ELECTRON MICROSCOPY is a type of electron energy loss spectroscopy carried out in electron microscopes specially outfitted to analyze the spectrum of electron energy loss.

An analytical transmission electron microscopy method using an electron microscope fitted with an energy filtering lens. The method is based on the principle that some of the ELECTRONS passing through the specimen will lose energy when they ionize inner shell electrons of the atoms in the specimen. The amount of energy loss is dependent upon the element. Analysis of the energy loss spectrum (ELECTRON ENERGY-LOSS SPECTROSCOPY) reveals the elemental composition of a specimen. It is used analytically and quantitatively to determine which, how much of, and where specific ELEMENTS are in a sample. For example, it is used for elemental mapping of PHOSPHORUS to trace the strands of NUCLEIC ACIDS in nucleoprotein complexes.

Identification and measurement of ELEMENTS and their location based on the fact that X-RAYS emitted by an element excited by an electron beam have a wavelength characteristic of that element and an intensity related to its concentration. It is performed with an electron microscope fitted with an x-ray spectrometer, in scanning or transmission mode.

Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.

The chemical reactions involved in the production and utilization of various forms of energy in cells.

The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).

Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).

Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.

Total number of calories taken in daily whether ingested or by parenteral routes.

Computer-assisted study of methods for obtaining useful quantitative solutions to problems that have been expressed mathematically.

The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)