Heterogeneous
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{{Wiktionary}}
'''Heterogeneous''' is an adjective used to describe something that has a large number of variants or different forms. Derived from the Greek; "έτερος" heteros or 'other' and "γένος" genos or 'kind'. It is the opposite of ''[[Homogeneous|homogeneous]]'', which means that an object or system consists of many identical items. [[Matter]]s of a [[quantum]] can exist in [[homogenous]] or in heterogeneous or in combined [[Distribution function|distribution]]s. The term is often used in a [[science|scientific]] (such as a kind of [[catalyst]]), [[mathematics|mathematical]], [[sociology|sociological]] or [[statistics|statistical]] context.
A heterogeneous compound, mixture, reaction or other such object is one that consists of many different items, which are often not easily sorted or separated, though they are clearly distinct.
A ''heterogeneous mixture'' is a [[mixture]] of two or more [[Chemical compound|compounds]].
In chemical kinetics, a ''heterogeneous reaction'' is one that takes place at the interface of two or more i.e. between a solid and a gas, a liquid and a gas, or a solid and a liquid.
*[[amorphous]]
*[[heterozygous]]
*[[heteroazeotrope]]
*[[homogenization]]
*[[homozygous]]
*[[mesoporous silicates]]
= Statistics =
In [[meta analysis]] the term refers to the presence of multiple non-random intercepts in a dataset. In Meta-analysis of clinical studies which involves comparing and quantifying the effects of separate studies, heterogeneity refers to the differences in study populations or in methodologies used to study them that may have the effect of reaching differing conclusions. This is a problem as it calls into question conclusions that are drawn from studies and reduces their comparability. The following concepts are important in understanding the importance of heterogeneity in meta-analytical research.
'''Clinical Heterogeneity:'''
Heterogeneity resulting from differences in clinical features of a population that is being studied or treated.
'''Methodological Heterogeneity:'''
Heterogeneity resulting from the differential use of study methodology. These may lead to different conclusions in different studies, despite their clinical characteristics being the same.
'''Statistical Heterogeneity:'''
Heterogeneity resulting from either clinical or statistical heterogeneity, which leads to a difference in expected results, more than which can be accounted for by chance.
==Systems==
In the world of enterprise computing, ''heterogeneous data'' is a mix of [[data]] from two or more sources, often of two or more formats, e.g., [[SQL]] and [[XML]].
Distributed systems are called ''heterogeneous'' if they contain many different types of hardware and software.
===See also===
[[Distributed computing]]
==Social and human science==
''Homogeneity'' and ''heterogeneity'' are terms used to describe variety in many aspects of human groups, communities and populations, including cultural, demographic, ethnic and socio-political. In [[Economics]] and [[Social Sciences]], 'heterogeneous agents' refers to a set of [[Agent (economics)|agents]] with different properties. The opposite of 'heterogeneous agents' in economic terminology is '[[representative agent]]'.
== General ==
In [[taxonomy]], a ''heterogeneous taxon'' is a taxon that contains a great variety of individuals or sub-taxa; usually this implies that the taxon is an artificial grouping.
== Genetics ==
In genetics, heterogeneity refers to multiple origins causing the same disorder in different individuals.
=== Allelic heterogeneity ===
If a number of different mutations occurring the same [[gene]] produce disorders, it is said to manifest ''allelic heterogeneity''.
This term has been used when a number of different alleles cause a similar [[phenotype]] or different phenotypes.
'''Example diseases:'''
* Different FBN1 mutations causing [[Marfan's syndrome]]
* [[Cystic fibrosis]] is caused by greater than 900 different mutant alleles
* Alpha-[[Thalassemia]] or [[sickle cell anemia]] can be caused by different mutations in alpha-globin gene.
=== Locus (Non-allelic) Heterogeneity ===
If mutations at a number of different loci, usually in different genes, all result in the same disorder (phenotype), such disorder is said to manifest ''locus heterogeneity''.
'''Example Disease:'''
* [[Retinitis Pigmentosa]] has autosomal dominant, autosomal recessive, and X-linked causes.
[[Category:Physical chemistry]]
[[Category:Disambiguation]]
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[[de:Heterogenität]]
[[es:Sistema heterogéneo]]
[[he:הטרוגניות]]
[[ru:Гетерогенная система]]
[[sl:Heterogen]]
[[tr:Heterojen]]