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element

 [el´ĕ-ment]
1. any of the primary parts or constituents of a thing.
2. in chemistry, a simple substance that cannot be decomposed by ordinary chemical means; elements are the basic components of which all matter is composed.

Chemical elements are made up of atoms, each of which consists of a nucleus with a cloud of negatively charged electrons revolving around it. The two major components of the nucleus are protons and neutrons. The number of protons in the atoms of a particular element is always the same, and therefore the physical and chemical properties of the element are always the same. It is possible, however, for a chemical element to exist in several different forms, the difference depending on the number of neutrons in the nucleus of its atoms. Different forms of the same element are called isotopes.

There are at least 105 different chemical elements known. (See Appendix 6 for a list of the elements, and the symbol, atomic weight, and atomic number of each.) The atomic number of an element is determined by the number of protons in the nucleus of one of its atoms. The mass number of an isotope is determined by the total number of neutrons and protons in the nucleus.
Stable Chemical Elements. A stable chemical element is one that contains an optimal ratio or range of ratios between the number of protons and neutrons in the nucleus. A stable element does not spontaneously transmute into another element and therefore does not give off radiation. The stable elements are those that have an atomic number below 84, except for a few, such as potassium and rubidium, which are weakly radioactive.
Radioactive Chemical Elements. A radioactive chemical element does not contain an optimal proton-to-neutron ratio in its atomic nuclei and therefore readily gives off nuclear particles until all nuclei have attained the optimal combination of protons and neutrons. The spontaneous releasing of its nuclear particles changes the radioactive atom into a new atom (transmutation).ƒ

As radioactive elements disintegrate and form new chemical elements, a tremendous amount of energy is released. This emission of energy and nuclear particles is called radiation. The radiations may be electrically charged particles having size and mass, such as alpha particles and beta particles, or they may be nonparticulate and contain no electrical charges, such as gamma rays. Most radioactive elements give off either alpha or beta particles and at the same time emit gamma radiation.
formed e's of the blood the blood cells.
trace element a chemical element present or needed in extremely small amounts by plants and animals; such elements include manganese, copper, cobalt, zinc, and iron.

el·e·ment

(el'ĕ-ment),
1. A substance composed of atoms of only one kind, that is, of identical atomic (proton) number, that therefore cannot be decomposed into two or more elements and that can lose its chemical properties only by union with some other element or by a nuclear reaction changing the proton number.
2. An indivisible structure or entity.
3. A functional entity, frequently exogenous, within a bacterium, such as an extrachromosomal element.
[L. elementum, a rudiment, beginning]

element

EBM
In the context of a trial design, a basic unit of time within a clinical trial, which describes what is expected to happen to the subject (patient) during the period, when the period begins and rules for ending the element.

Informatics
A section of text in an XML document delineated by start and end tags, or, in the case of empty elements (elements with no content, only attributes), indicated by an empty tag.

el·e·ment

(el'ĕ-mĕnt)
1. A substance composed of atoms of only one kind, i.e., of identical atomic (proton) number, which therefore cannot be decomposed into two or more elements, and which can lose its chemical properties only by union with some other element or by a nuclear reaction changing the proton number.
2. An indivisible structure or entity.
3. A functional entity, frequently exogenous, within a bacterium, such as an extrachromosomal element.
[L. elementum, a rudiment, beginning]

element

(el'e-ment) [L. elementum, a rudiment]
Enlarge picture
TABLE OF ELEMENTS IN THE BODY
In chemistry, a pure substance consisting of only one type of atom. Further breakdown by nonchemical means of an element results in subatomic particles (protons, neutrons and electrons), which are indistinguishable from those from other elements. Elements exist in free and combined states. There are 110 named elements and others yet to be fully characterized and named. See: illustration

Oxygen, carbon, hydrogen, nitrogen, phosphorus, and sulfur are found in all living organisms. These six elements and calcium make up 99% of the human body mass. Sodium, potassium, magnesium, chlorine, iodine, and iron form 0.9% of the body mass.

mobile element

A nucleotide sequence that can be inserted successfully into several different places in the genome.

movable genetic element

Transposon.

rare earth element

One of a series of metallic elements that follow lanthanum (at. no. 57) in the periodic table of elements and that have oxides with similar properties. The series comprises the 14-element lanthanide series (at. nos. 58-71 and includes praseodymium, promethium, and ytterbium.

trace element

An element needed by the body in very small amounts; many are essential for enzyme functioning. Trace elements include chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, and zinc.

ultratrace element

Any of those elements for which laboratory animals seem to have tiny dietary requirements, typically less than 1 µg/g. Elements in this category include arsenic, boron, bromine, cadmium, chromium, fluorine, lead, lithium, molybdenum, nickel, silicon, tin, and vanadium.

element

a pure substance consisting of only one type of atom, that cannot be destroyed by normally available heat or electrical energy.

el·e·ment

(el'ĕ-mĕnt)
Substance composed of atoms of only one kind that therefore cannot be decomposed into two or more elements and can lose its chemical properties only by union with another element or by nuclear reaction changing the proton number.
[L. elementum, a rudiment, beginning]

Patient discussion about element

Q. what consider to be a good nutrition for children? does it has to include some specific nutrition elements?

A. there's many things you should consider about children's nutrition, the amount of books written about kids nutrition can fill a library...
vitamins, organic vs industrial, fast food vs home made etc.
here are 2 video libraries that i'm sure you'll find all the info you seek in them-

http://www.thedoctorsvideos.com/categories/26/Nutrition

http://www.drmdk.com/html/nutrition.html

More discussions about element
References in periodicals archive ?
Moreover, mineral substances may enter the lichens in the form of dust which contains many chemical elements. The soils of the Barguzin-Chivyrkuysky land bridge are predominantly channery, easy-washed by precipitations and wind-moving in case of vegetation absence.
The Bioaccumulation Quotient (BQ) for chemical elements was calculated as follows:
The analysis of the graphs showed that Mn has the largest influence due to the number of links established with other chemical elements. For a confidence probability P = 95%, Mn have two links and for P = 99%, Mn have only a link.
(1) The dynamics of chemical elements in decomposing litter is determined mainly by two factors: (1) decomposer requirements for nutrients (biological factor), and (2) the chemical affinity of ions to humic substances produced in the course of a decay process (chemical factor): the higher the affinity to humic substances, the more important the chemical factor.
"This hotbed of star formation is colored according to the chemical elements present," NASA said in a (https://www.nasa.gov/feature/goddard/2017/messier-17-the-omega-nebula-or-swan-nebula) statement .
According to the NTSEC, the United Nations has designated 2019 as the International Year of the Periodic Table of Chemical Elements. Since Matheatre is currently on an Asian tour, the NTSEC invited them to Taiwan for a week to produce the show and bring the story of Marie Curie to life.
Aerosol science is a discipline specialising in monitoring air quality and chemical elements in the air.
Summary: TEHRAN (FNA)- As the 150th anniversary of the formulation of the Periodic Table of Chemical Elements looms, a Michigan State University professor probes the table's limits in a recent Nature Physics Perspective.
According to him, radiation level has been increased after the a pipe with chemical elements of the enriching factory has broken down in the village and the river was contaminated with the chemical wastes.
Group Theory of Chemical Elements: Structure and Properties of Elements and Compounds
Alexander Ji of MIT and collaborators used the Magellan telescopes in Chile to catalog chemical elements in nine of Reticulum ll's stars.

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