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Talk:Combinatorial chemistry

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Untitled
Somebody who really knows all about QSAR and similar bits of alphabet soup could add to this article. -- Marj Tiefert, Friday, May 17, 2002

improve it?
Marj, i´ve read the article and maybe we can improve it. There is a "term" coined in the scientific literature called Virtual HTS, e. g.: testing all the library members against its molecular target (a enzyme or a membran protein in most of the cases) in a computer, before the synthesis. Many things in the Combinatorial media are changing, specially the quantity of members in a comb. library, that is decreasing. What do you think about it? --Cedric.graebin 16:38, 17 August 2005 (UTC)

Truth or fiction? Do we care?
Here is the text of a POV edit I am removing from the article. Please comment. If majority opinion supports inclusion, then it will get put back into the text.

 * The first publication of a combinatorial library was by G. Pieczenik in 1987, with the publication of his foreign patent filings of the US patent 5,866,363 filed in 1985 with a disclosure document in 1983. http://www2.mrc-lmb.cam.ac.uk/archive/g_pieczenik.html. Pieczenik worked with Bruce Merrifield and Fred Sanger, among other Nobel laureates. A. Furka had a notarized copy of his idea of making mixed combinatorial libraries in 1982.http://www.chem.elte.hu/departments/szerves/szerves/Furka/ConcealedHTML.htm

 * 1) Remove: ~K 04:21, 5 September 2006 (UTC)
 * 2) Remove in part, reduce level of detail: From the tone, it sounds like the point of the Furka note is to cast aspersions on the originality of others cited, or at the outside extreme some conspiracy theory. Really need something more than just an interview with the person to consider including this. Notarized ideas aren't how science works. Regardless, need to keep claims and dates of originality on equal footing--everyone has ideas and preliminary/promising result leads long before an actual publication. The first sentence seems like reasonable material, but the level of detail about the patent is excessive. Regarding the earlier part of the paragraph, consider instead "The first publication of a combinatorial library was by G. Pieczenik in a patent disclosed in 1983 [ ref to the patent itself, or a secondary source about it ] ." The intricacies of what secondary contries got the patent and the timeline of the whole patent process aren't important. DMacks 00:12, 13 September 2006 (UTC)
 * 3) Remove - at least, this is the opinion that I think would be best for the article. If anything, that material can be added to something like History of Combinatorial Chemistry. --HappyCamper 22:45, 13 September 2006 (UTC)
 * 4) Remove Not helpful to the reader it seems to only involve some sort of legal establishment of facts for a patent dispute. If there is a patent dispute it could be mentioned as a dispute but only as a foot note. This article is about cominatorial chemistry not about who invented it. Yes the4 inventor could be mentioned but only if well established otherwise leave it out.--Nick Y. 01:39, 14 September 2006 (UTC)

Furka's 1982 statement is available at here. In Hungary some regard him as THE founder of combinatorial chemistry (e.g. Istvan Hargittai, who frequently writes on the Nobel prize, sometimes mentioning that Furka surely deserves one). It would be good to know what exactly his part was in inventing combinatorial chemistry. Kope (talk) 13:58, 5 January 2008 (UTC)

Basics of Combinatorial Chemistry
There ought to be some basic mathematical coverage on Combinatorial Chemistry. For example, given M molecular types, there will be, abstractly: 76.166.236.65 (talk) 05:55, 1 May 2011 (UTC)

PotentialNewMoleculeProductionNodes = (2^M -1), and

ActualNewMoleculeProductionNodes = c*(2^M -1),

for any one iteration of analysis of Combinatorial Chemistry. Likewise, in Graph Theory, reactions networks are formed, from the base molecules, forming graphic networks of effective reactions, and feedback networks, for auto-reactive systems, that form multiple rings of self-reactions. 76.166.236.65 (talk) 05:55, 1 May 2011 (UTC)

For example, with 12 molecules in a water sample, there could be a pedagogical example of molecule system iteration: 76.166.236.65 (talk) 05:55, 1 May 2011 (UTC)

FIRST ITERATION

ActualNewMoleculeProductionNodes = c*(2^12 -1) = c*(4096-1), with c=0.001

ActualNewMoleculeProductionNodes = 4

(12 molecules -> 16 molecules)

SECOND ITERATION

ActualNewMoleculeProductionNodes = c*(2^(12+4) -1) = c*(65536-1), with c=0.001

ActualNewMoleculeProductionNodes = 65

(16 molecules -> 81 molecules)

THIRD ITERATION

ActualNewMoleculeProductionNodes = c*(2^(12+4+65) -1) = c*(2.4*10^24), with c=0.001

ActualNewMoleculeProductionNodes = 2.4*10^21

(81 molecules -> near infinite molecule specie variety)

showing the explonetial power of combinatorial chemistry, and the very small "reactive molecule generative" c required in a system, to increase the number of durable reactive molecules exponentially.

Also, there should be some discussion of non-equilibrium systems, like closed mass systems, that are exposed to, say, light and darkness, of systems like a derivative of Miller Urey experiments, that are capable in Combinatorial Chemistry, of forming photon absorbing and energy storing sugar like molecules and molecular system netwokrs under daylight, and stored energy molecule decomposition in darkness, forming a basic photo-synthetic matabolic network like reaction in Combinatorial Chemistry System, akin to Alexander Oparin Abiogenesis theories from the 1920's. And also under non-equilibrium Combinatorial Chemistry molecular systems, are reaction networks that also arise, consuming such photo-synthetic energy storing molecules, in "carnivore" like energy consumption of the photo-synthetic energy storing molecules, all in a non-equilibrium Combinatorial Chemistry molecular system of extreme complexity. Likewise, the enemy concept of Intelligent Design, that persists in amazing perclusion of any potential complexity arising from simplicity, which can be attacked through a direct approach, that is effective against all but the most fundamental ignorant familiarity of dogma reactive system mathematics and graphs. 76.166.236.65 (talk) 05:55, 1 May 2011 (UTC)

 * then why are you adding this information only to the discussion page, instead of including it? Do you want some one else to do it for you128.214.69.81 (talk) 08:51, 1 November 2012 (UTC)

Removalism
There has been large chunks of materials removed from the article. The comments were trying to justify some of them but as far as I see they were based on wrong assumptions. I am not involved in the discussion and not related to anyone here and called in as an arbitrator.

As far as I see (and I'm in a good position since I understand both English and Hungarian materials) Prof. Furka inserted large amounts of information and background on this part of chemistry which was either funded by him or considerably base on his work; he inserted references in a way scientific publication requires it (basically references every theory or method), and tried to reflect the science and history behind the topic from his view (since he's a human after all), with no visible outrageous bias.

First batch of removals were removing the references with the "borderline spam" comment and I guess this was quite unjust. If you observe the references they follow the science publication way and if it's not proper for a wikipedia article the excess can be removed or gathered at the bottom, but not all of them and not with hostile comments.

Considering the patent issue and whether he or someone else have invented the topic: it is an important part of the article but it's not the central one. It is quite clear for me why it wasn't patented in Hungary in 1982 (the system in th so called "communist era" worked way different here) so I see why he tried to have some document to prove that he actually invented it, but it's way too much detail for a WP article, I agree. Still, it is a proof of timeline, so for me it's quite obvious that his work predated the patented methods in the US, and I see why someone would like to have this information, which may be one of his scientific breakthroughs.

The article could be wikified, and possibly some refs removed, and maybe some events trimmed (I've tried to trim the most obvious ones), but please refrain from mass removal and impolite comments. Wikipedia policy prefers to have external sources and references, more than ever. And Prof. Furka may be one who have created the science we're writing about, my guess he deserves some respect, applied with good wikipedian judgement, as we all probably prefer. :-)

Thank you. --grin ✎ 14:05, 21 February 2013 (UTC)

Material moved to talk, for discussion
Note, I have no opinion on the scientific or historical claims being made in the following redacted material. The material was removed to Talk, because of issues with the way in which text and citations are being used to make the scientific and historical claims. This edit is purely procedural, and without bias as to how the argument finally settles (here or elsewhere).

1. Reference removed because its support for the very general statements being made in the lede could not be verified, and it was the only reference to currently appear in the lede. Critically, this citation is to a conference presentation, and not to a published, refereed source, and is of limited content and availability, and so not is a standard, reputable secondary source. It is not sufficient as a source to support a general statement in the lede—or for that matter, anywhere else in an encyclopedic article. The source was replaced, in the lede, with a tag:
 * Ref>Á. Furka, F. Sebestyén, J. Gulyás, Computer made electrophoretic peptide maps. Proc. 2nd Int. Conf. Biochem. Separations, Keszthely, Hungary, pp. 35-42 (1988).

2. Paragraph removed because of POV issues, and/or piecemeal approach to subject's founding and history:

The issues with this paragraph are as follows:
 * Opening sentence: One cannot use a review article by an individual scientist to establish, at Wikipedia, that she or he (that same author) was the founder of the field; it requires several reputable independent secondary sources and even text books making this claim.
 * Second sentence: One cannot use a patent by an individual scientist to establish, at Wikipedia, that she or he (that patent submitter) was first to perform a particular procedure; it requires several reputable independent secondary sources making this claim.
 * Next statement makes a further historical claim, but has sat unreferenced for more than a year.
 * Next statement is a solid secondary source then appears citing Bunin-Ellman work; this was removed only because, i, to leave it would leave a single historical sentence remaining, and ii, even if all were left in, it would be a single reputable source, leaving sparse historical coverage in the field (1980s, jump, 1992, jump).

Bottom line, the whole article needs serious work, but this set of entries is so egregiously misguided in construction (Bunin-Ellman sentence excepted), that it had to be moved here, for discussion.

Note: If this move is reverted and no serious chemistry and history work done on this section, I will call in Admins to review, because from my perspective, this addresses claims of primacy by persons living, and so it is both an important scientific POV issue, as well as being a BLP matter.

Le Prof Leprof 7272 (talk) 05:29, 6 June 2014 (UTC)

The whole article is a bloody mess
…and a nightmare for any serious chemist to contemplate editing into a passable article, Sorry, one opinion. How it got here, no matter. Where it goes—someone with expertise needs to come in and gut it: then with what remains create a decent article outline and stub. If one comes to it to edit in this shape, one simply cannot easily begin to add good solid material from secondary and tertiary sources. Until it is put into a form to receive good material, it will be any easy place to add further junk material, and will not easily be turned into a useful article. Again, one opinion. Le Prof Leprof 7272 (talk) 05:43, 6 June 2014 (UTC)
 * remove all unreferenced text to Talk;
 * remove all primary referenced text, and all primary references, to Talk, and
 * Some unreferenced text was removed in a recent revision of this article. Does anything else need to be done here? Jarble (talk) 00:04, 8 January 2017 (UTC)

An offer to write an unbiased set of wiki articles to 'fix' the problems with the current Combinatorial Chemistry wiki article
Colleagues: I was appointed the Founding Editor of the American Chemical Society's Journal of Combinatorial Chemistry (now ACS Combinatorial Science) and served in that capacity from 1998-2010. . I took on the role as Editor because the young field was not being represented by appropriate Reviewers; I felt this could only be remedied by starting a specialized journal. Given the broad expansive of ideas, experiments, and inventions over the past 30 years, I certainly lay no claim to any special status in making indispensable contributions to this field; i.e., I'm not doing PR for a Nobel Prize canonization. But history will show that advances in combinatorial chemistry led to enormous improvements in the discovery of substances with important properties.

I offer to write entries that represent timelines of published contributions and to try to place them into a context of 'importance'. If those who make such decisions at Wikipedia would like to speak with me about my proposal, I can be reached at ACzarnik@unr.edu.

Anthony Czarnik https://www.unr.edu/chemistry/people/anthony-czarnik

Tony (talk) 08:38, 28 June 2017 (UTC)

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title: Talk:Combinatorial chemistry


text:
Rafflesia

Rafflesia, or stinking corpse lily, is a genus of parasitic flowering plants in the family Rafflesiaceae. The species have enormous flowers, the buds rising from the ground or directly from the lower stems of their host plants; one species has the largest flower in the world. Plants of the World Online lists up to 41 species from this genus, all of them are found throughout Southeast Asia.

Western Europeans first learned about plants of this genus from French surgeon and naturalist Louis Deschamps when he was in Java between 1791 and 1794; but his notes and illustrations, seized by the British in 1803, were not available to western science until 1861. The first British person to see one was Joseph Arnold in 1818, in the Indonesia rainforest in Bengkulu, Sumatra, after a Malay servant working for him discovered a flower and pointed it out to him. The flower, and the genus, was later named after Stamford Raffles, the leader of the expedition and the founder of the British colony of Singapore.

The following is from Arnold's account of discovering the flower: "Here I rejoice to tell you I happened to meet with what I consider as the greatest prodigy of the vegetable world. I had ventured some way from the party, when one of the Malay servants came running to me ... To tell you the truth, had I been alone, and had there been no witnesses, I should, I think, have been fearful of mentioning the dimensions of this flower, so much does it exceed every flower I have seen or heard of."

Vivid contemporary accounts documenting some of the most inaccessible species of Rafflesia are described in the popular science book, Pathless Forest: The Quest to Save the World's Largest Flowers, by botanist Chris Thorogood based at the University of Oxford Botanic Garden.

Description
The plant has no stems, leaves or roots. It is a holoparasite of vines in the genus Tetrastigma (a plant in the Vitaceae, the grape vine family), spreading its absorptive organ, the haustorium, inside the tissue of the vine. The only part of the plant that can be seen outside the host vine is the five-petalled flower. In some species, such as Rafflesia arnoldii, the flower may be over 100 cm in diameter, and weigh up to 10 kg. A Rafflesia that flowered in West Sumatra in 2019 was measured to be almost 4 ft in diameter, the largest flower ever recorded – 4 in wider than the flower reported as the largest in 2017. Even one of the smallest species, R. baletei, has 12 cm diameter flowers. A team of morphologists and geneticists headed by Prof. Charles Davis of Harvard has discovered an important difference  between Rafflesia spp. and the very similar Sapria spp. In both genera the petals are now described as sepals (or more correctly as "petaloid tepals") instead of vaguely defined "perigon lobes". In Sapria, the "diaphragm" is a true corona while in Rafflesia the diaphragm is made up of adnate petals to form a dome, the true corona being greatly reduced.

The flowers look and smell like rotting flesh. The foul odour attracts insects such as carrion flies, which transport pollen from male to female flowers. Most species are dioecious, having separate male and female flowers, but a few (R. baletei and R. verrucosa) have hermaphroditic flowers. Little is known about seed dispersal. Tree shrews and other forest mammals eat the fruits. The extremely tiny seeds have extremely tiny elaiosomes, and are thus most likely dispersed by ants. The seeds are packed into berries, each of which contains hundreds of thousands of seeds.

Because Amorphophallus has the world's largest unbranched inflorescence, it is sometimes mistakenly credited as having the world's largest flower. Both Rafflesia and Amorphophallus are flowering plants, but they are unrelated to each other. Rafflesia arnoldii has the largest single flower of any flowering plant, at least in terms of weight. Amorphophallus titanum has the largest unbranched inflorescence, while the talipot palm (Corypha umbraculifera) forms the largest branched inflorescence, containing thousands of flowers; the talipot is monocarpic, meaning the individual plants die after flowering.

Rafflesia are also remarkable for showing a large horizontal transfer of genes from their host plants. This is well known among bacteria, but not higher organisms. It occurs in the mitochondria (originally derived from bacteria) found within the cells of Rafflesia; these appear to have exchanged genes with the mitochondria of the host tissue.

Names
In Indonesian and Malaysian, it is known as padma. The species R. arnoldii is known as padma raksasa ("giant padma"). In Javanese it is called patma. In Malay, the 'normal' R. hasseltii is vernacularly known as pakma, patma or ambai-ambai, whereas the goliath R. arnoldii from Sumatra is called krubut or kerubut, 'great flower'. The words padma, pakma or patma originate etymologically from the word पद्म (padma), Sanskrit for 'lotus'.

In English Rafflesia is known as the stinking corpse lily. It is also known as "corpse flower", or bunga bankai in Indonesian, a name that more commonly refers to the titan arum (Amorphophallus titanum) of the family Araceae. The type species arnoldii has been called the "monster flower".

Taxonomy
Robert Brown introduced the genus Rafflesia to the wider scientific world in a presentation before the Linnean Society of London in June 1820, but his scientific paper on the subject was only published in late 1821.

In 1999 the British botanical historian David Mabberley pointed out that the genus Rafflesia was first validated by an anonymous report on the meeting published in the Annals of Philosophy in September 1820 (the name was technically an unpublished nomen nudum until this publication). Mabberley claimed the author was Samuel Frederick Gray. However, as that is nowhere stated in the Annals, per Article 46.8 of the code of ICBN, Mabberley was wrong to formally ascribe the validation to Gray. The validation of the name was thus attributed to one Thomas Thomson, the editor of the Annals in 1820, by the IPNI. Mabberley admitted his error in 2017. This Thomson was not the botanist Thomas Thomson, who was three years old in 1820, but his identically named father, a chemist.

Evolution and phylogeny

Comparison of mitochondrial DNA (mtDNA) sequences of Rafflesia with other angiosperm mtDNA indicated this parasite evolved from photosynthetic plants of the order Malpighiales. Another 2004 study confirmed this result using both mtDNA and nuclear DNA sequences, and showed the three other groups traditionally classified in Rafflesiaceae were unrelated. A 2007 study more specifically found Rafflesia and its relatives to be embedded within the family Euphorbiaceae as traditionally circumscribed, which was surprising, as members of that family typically have very small flowers. According to their analysis, the rate of flower size evolution was more or less constant throughout the family except at the origin of Rafflesiaceae, where the flowers rapidly evolved to become much larger before reverting to the slower rate of change.

To maintain monophyletic families, in 2016 the APG IV system separated the family Peraceae from the Euphorbiaceae. A summary cladogram is shown below, with family placements in the APG IV system.

A 2010 molecular phylogenetic study of 18 species of Rafflesia found that they fell into four clear-cut geographically defined groups:

However, the clear monophyly of the four geographical clades does not correspond to any clear difference in appearance. There is no consistency within the clades in the size of flowers, or the presence or absence of white warts; species in different clades resemble one another more than they do some other species within the same clade. Homoplasy – repeatedly gaining or losing traits – seems to be the rule within Rafflesia.

Accepted species
, Plants of the World Online accepted the following species:
 * Rafflesia arnoldii – Sumatra, Borneo
 * Rafflesia aurantia – Philippines (Luzon)
 * Rafflesia azlanii – Peninsular Malaysia
 * Rafflesia baletei – Philippines (Luzon)
 * Rafflesia banaoana Malabrigo – Philippines (Luzon); treated as a synonym of R. leonardi by other sources
 * Rafflesia bengkuluensis – Sumatra (Indonesia)
 * Rafflesia borneensis Koord. – Indonesian Borneo (northeast Kalimantan)
 * Rafflesia camarinensis F.B.Valenz., Jaucian-Adan, Agoo & Madulid – the Philippines
 * Rafflesia cantleyi – Peninsular Malaysia
 * Rafflesia ciliata Koord. – Indonesian Borneo (northeast Kalimantan)
 * Rafflesia consueloae – Philippines (Luzon)
 * Rafflesia gadutensis – Sumatra (Indonesia)
 * Rafflesia hasseltii – Sumatra
 * Rafflesia horsfieldii R.Br. – West Java (Indonesia)
 * Rafflesia keithii – Borneo
 * Rafflesia kemumu Susatya, Hidayati & Riki – Sumatra (Indonesia)
 * Rafflesia kerrii – Thailand, Peninsular Malaysia
 * Rafflesia lagascae – Philippines (Luzon)
 * Rafflesia lawangensis – Sumatra
 * Rafflesia leonardi – Philippines (Luzon)
 * Rafflesia lobata – Philippines (Panay)
 * Rafflesia manillana – Philippines (Samar)
 * Rafflesia meijeri Wiriad. & Sari – North Sumatra, Indonesia
 * Rafflesia micropylora – Sumatra
 * Rafflesia mira – Philippines (Mindanao)
 * Rafflesia mixta – Philippines (Mindanao)
 * Rafflesia parvimaculata Sofiyanti, K.Mat-Salleh, Khairil, Zuhailah, Mohd.Ros. & Burs – Peninsular Malaysia
 * Rafflesia philippensis – Philippines (Luzon)
 * Rafflesia pricei – Borneo
 * Rafflesia rochussenii – Java, Sumatra
 * Rafflesia schadenbergiana – Philippines (Mindanao)
 * Rafflesia sharifah-hapsahiae J.H.Adam, R.Mohamed, Aizat-Juhari & K.L.Wan – Peninsular Malaysia
 * Rafflesia speciosa – Philippines (Panay)
 * Rafflesia su-meiae M. Wong, Nais & F.Gan – Peninsular Malaysia
 * Rafflesia tengku-adlinii – Borneo (Sabah)
 * Rafflesia tiomanensis Siti-Munirah, Salamah & Razelan – Pulau Tioman, Peninsular Malaysia
 * Rafflesia tuan-mudae – Borneo (Sarawak)
 * Rafflesia tuanku-halimii J.H.Adam, Aizat-Juhari, Azilah & K.L.Wan – Peninsular Malaysia
 * Rafflesia verrucosa – Philippines (Mindanao)
 * Rafflesia witkampii Koord. – Indonesian Borneo (East Kalimantan)
 * Rafflesia zollingeriana Koord. – East Java (Indonesia)

Other names

 * Rafflesia patma – Java; considered a synonym of R. horsfieldii by Plants of the World Online, apparently based on the confused writings of a British historian of botany, although R. horsfieldii, for which no specimens were ever collected, only a drawing made which was lost centuries ago, is not considered a valid taxon by Rafflesia experts.
 * Rafflesia titan – A synonym of R. arnoldii; it was in fact validly published earlier, being rushed to publication in Singapore in 1820 by a British botanist who feared that the French, who had actually discovered a species before the British, might deny the glory of the species description to servants of the British Empire. In order to retain the honour of naming the species to the famous British scientist Robert Brown, the historian of botany mentioned above chose to pretend a 1821 pre-print Brown sent to a colleague was a valid 'effective publication', which has been accepted by the relevant British institutions.

Loss of the chloroplast genome
Research published in 2014 revealed that one Philippine Rafflesia species from the island of Luzon, R. lagascae (a synonym of R. manillana), may have lost the genome of its chloroplast and it is speculated that the loss happened due to the parasitic lifestyle of the plant.

Malay Peninsula
Rafflesia can be found along the area of Peninsular Malaysia and Thailand in the Malay Peninsula.

Malaysia
In Peninsular Malaysia, the flower can be found in few states, such as Kelantan, Pahang, Perak and Terengganu. In Perak, three species of the flower can be found in Royal Belum state park and Gerik forest reserve of which are Rafflesia kerrii, Rafflesia cantleyi and Rafflesia azlanii. Rafflesia azlanii was named after the Sultan of Perak, Sultan Azlan Shah. Meanwhile, two species of the flower hosted by Tetrastigma Planch can be found in three location in Kelantan. The Rafflesia cantleyi species can be found in Ulut Sat and Chabang Tongkat while Rafflesia kerrii can be found in Lojing. Furthermore, two locations in Pahang where this flower can be found are Lembah Benum forest reserve and Lata Jarum. For Terengganu, the flower of Rafflesia Cantleyi species can be found in Kuala Berang. A flower has been found in this area hanging on the root of its host three metres above the ground, unlike the common flowers found on the ground roots.

The locations of these flowers are turned into tourist attractions for biodiversity lovers and hikers and helps to generate income for the local people.

Thailand
In Thailand Rafflesia can be observed in Khao Sok National Park where the flowers are numbered and monitored by the park rangers.

Greater Sunda Islands
Species native to Borneo include Rafflesia arnoldii, R. cantleyi, R. hasseltii, R. keithii, R. kerrii, R. pricei, R. tengku-adlinii and R. tuan-mudae. R. arnoldii boasts the world's largest single bloom.

R. keithii is an endemic species in Sabah and the largest among the three species of Rafflesia found in Sabah. The flower size is between 60 cm to 80 cm. Due to its size, the flower is generally found on the forest floor growing on the underground stem or root of Tetrastigma lanceolarium. R. keithii can be mostly found around the area of Poring, Sabah.

Mindanao species
The Mindanao species is known as Rafflesia schadenbergiana, after the naturalist Alexander Schadenberg, who first discovered the species at the foothills of Mount Apo in 1882. With a flower of nearly a meter, it is close to the size of a seated child. On Mindanao, the species has been seen in Davao del Sur, South Cotabato and Mount Kitanglad in Bukidnon. R. mira and R. magnifica are two names for a single species. Both were discovered at Mount Candalaga in Maragusan, Compostela Valley. The two forms differ in size measurements in which the scientific description of R. magnifica came from measurements of flowers in full bloom while that of R. mira was from photographs of nearly dead samples. The medium-sized R. mira flowers measure about half a meter in diameter and they have round or elliptic perigone wart. The third species on Mindanao is the R. mixta which has only been found so far in the town of Mainit, Surigao del Norte. It shows a combination of three features of Philippine Rafflesia, namely: the shape and size of the conical process in R. schadenbergiana, the floral size and sparsely distributed perigone warts of R. speciosa, and the overall resemblance, floral size, faint scent, diaphragm and ramenta morphology of R. mira. A fourth species is Rafflesia verrucosa which is found only in Mount Kampalili in Davao Oriental Province.

Ecology
Species of Rafflesia are all thought to be holoparasites of lianas of the genus Tetrastigma, vines which belong to the Vitaceae, the family of the grape vines. They are thus, in a way, hyperparasites, because Tetrastigma are themselves, in a way, structural parasites of the trees they use to climb up to the light. Rafflesia appear to be species-specific, with each Rafflesia species naturally only growing on one to three species of Tetrastigma. Of the 57 known species of Tetrastigma, only ten are known to be host plants. Of the 30 odd species of Rafflesia, the host plants are only known from about half of the species. A certain species of Tetrastigma is very popular among Rafflesia: T. tuberculatum is a host plant for at least 15 species, and only two Philippine species are not known to infect it. T. papillosum and T. diepenhorstii both host at least two species. The flowers may bud from different locations; R. cantleyi flowers from the vine some two meters from the ground, whereas R. zollingeriana always buds out of the roots and appears out of the ground.

The gender ratio may be skewed. In R. lobata there are approximately nine male flowers for every female flower. Rarely are there flowers of both sexes at one location to ensure pollination and thus sexual reproduction. This may not matter: female flowers usually form fruit anyway and may thus be agamospermous. Flowering is relatively constant, and sites may continue to flower for decades.

In Rafflesia arnoldii the flowers are visited by the flies Drosophila colorata, Chrysomya megacephala and Sarcophaga haemorrhoidalis. Black ants of the genus Euprenolepis may feed on the developing flower buds, perhaps killing them. Mammals which are known to eat the flowers are the Javan treeshrew Tupaia javanica and the porcupine Hystrix javanica. Mammals which have been recorded destroying the buds or flowers, often simply by stepping on and crushing them, are: pigs (Sus scrofa), wild cats (Prionailurus bengalensis), rusa (Cervus timorensis), muntjak (Muntiacus muntjak) and banteng (Bos javanicus).

Uses
In Thailand the buds and flowers of R. kerrii are considered a delicacy. They are also harvested for herbalism, a concoction is believed to act as a sexual stimulant and to help for fever or backache. In the Philippines the plants are also used in folk herbalism, but the flowers are also fed to swine as fodder. On Java the buds of R. zollingeriana are harvested and dried for use in jamu, the ancient traditional herbalism of the island. It is unknown for what the buds are supposed to be good for; jamu concoctions are often complex mixtures and often are supposed to help with sexual prowess.

These plants also have some economic use in attracting ecotourists.

Research in Malaysia and Indonesia has made it possible to propagate the species for use in horticulture, with the famous Bogor Botanical Garden growing the first plants in the 1850s using grafts of infected vines. The Malaysian biologist Jamili Nais was the first to propagate the plants using the seeds around the year 2000.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Rafflesia


text:
User:Turboalberta

[homepage]

title: User:Turboalberta


text:
MathML

Mathematical Markup Language (MathML) is a mathematical markup language, an application of XML for describing mathematical notations and capturing both its structure and content, and is one of a number of mathematical markup languages. Its aim is to natively integrate mathematical formulae into World Wide Web pages and other documents. It is part of HTML5 and standardised by ISO/IEC since 2015.

History
Following some experiments in the Arena browser based on proposals for mathematical markup in HTML, MathML 1 was released as a W3C recommendation in April 1998 as the first XML language to be recommended by the W3C. Version 1.01 of the format was released in July 1999 and version 2.0 appeared in February 2001. Implementations of the specification appeared in Amaya 1.1, Mozilla 1.0 and Opera 9.5. In October 2003, the second edition of MathML Version 2.0 was published as the final release by the W3C Math Working Group.

MathML was originally designed before the finalization of XML namespaces. However, it was assigned a namespace immediately after the Namespace Recommendation was completed, and for XML use, the elements should be in the namespace with namespace URL  http://www.w3.org/1998/Math/MathML . When MathML is used in HTML (as opposed to XML) this namespace is automatically inferred by the HTML parser and need not be specified in the document.

MathML version 3
Version 3 of the MathML specification was released as a W3C recommendation on 20 October 2010. A recommendation of A MathML for CSS Profile was later released on 7 June 2011; this is a subset of MathML suitable for CSS formatting. Another subset, Strict Content MathML, provides a subset of content MathML with a uniform structure and is designed to be compatible with OpenMath. Other content elements are defined in terms of a transformation to the strict subset. New content elements include which associates bound variables  to expressions, for example a summation index. The new element allows structure sharing.

The development of MathML 3.0 went through a number of stages. In June 2006, the W3C rechartered the MathML Working Group to produce a MathML 3 Recommendation until February 2008, and in November 2008 extended the charter to April 2010. A sixth Working Draft of the MathML 3 revision was published in June 2009. On 10 August 2010 version 3 graduated to become a "Proposed Recommendation" rather than a draft. An implementation of MathML 2 landed in WebKit around this same time, with a Chromium implementation following a couple of years later, although that implementation was removed from Chromium after less than a year.

The Second Edition of MathML 3.0 was published as a W3C Recommendation on 10 April 2014. The specification was approved as an ISO/IEC international standard 40314:2015 on 23 June 2015. Also in 2015, the MathML Association was founded to support the adoption of the MathML standard. At that time, according to a member of the MathJax team, none of the major browser makers paid any of their developers for any MathML-rendering work; whatever support existed was overwhelmingly the result of unpaid volunteer time/work.

MathML Core
In August 2021, a new specification called MathML Core was published, described as the “core subset of Mathematical Markup Language, or MathML, that is suitable for browser implementation.” MathML Core set itself apart from MathML 3.0 by including detailed rendering rules and integration with CSS, automated browser support testing resources, and focusing on a fundamental subset of MathML. An implementation was added to Chromium at the beginning of 2023.

Presentation and semantics
MathML deals not only with the presentation but also the meaning of formula components (the latter part of MathML is known as "Content MathML"). Because the meaning of the equation is preserved separate from the presentation, how the content is communicated can be left up to the user. For example, web pages with MathML embedded in them can be viewed as normal web pages with many browsers, but visually impaired users can also have the same MathML read to them through the use of screen readers (e.g. using the VoiceOver in Safari). JAWS from version 16 onward supports MathML voicing as well as braille output.

The quality of rendering of MathML in a browser depends on the installed fonts. The STIX Fonts project have released a comprehensive set of mathematical fonts under an open license. The Cambria Math font supplied with Microsoft Windows had slightly more limited support.

A valid MathML document typically consists of the XML declaration, DOCTYPE declaration, and document element. The document body then contains MathML expressions which appear in elements as needed in the document. Often, MathML will be embedded in more general documents, such as HTML, DocBook, or other XML-based formats.

Presentation MathML
Presentation MathML focuses on the display of an equation, and has about 30 elements. The elements' names all begin with m. A Presentation MathML expression is built up out of tokens that are combined using higher-level elements, which control their layout. Finer details of presentation are affected by close to 50 attributes.

Token elements generally only contain characters (not other elements). They include:
 * x – identifiers;
 * + – operators;
 * 2 – numbers;
 * such that – text.

Note, however, that these token elements may be used as extension points, allowing markup in host languages. MathML in HTML5 allows most inline HTML markup in mtext, and non zero is conforming, with the HTML markup being used within the MathML to mark up the embedded text (making the first word bold in this example).

These are combined using layout elements, that generally contain only elements. They include:
 * – a horizontal row of items;
 * ,, and others – superscripts, limits over and under operators like sums, etc.;
 * – fractions;
 * and – roots;
 * – surrounding content with fences, such as parentheses.

As usual in HTML and XML, many entities are available for specifying special symbols by name, such as π and →. An interesting feature of MathML is that entities also exist to express normally-invisible operators, such as  (or the shorthand ) for implicit multiplication. They are:
 * (to distinguish $$\sin(x)$$ from $$\sin\cdot x$$ in $$\sin{x}$$);
 * (to distinguish $$a_{m\times n}$$ from $$a_{m,n}$$ in $$a_{mn}$$);
 * (vice versa);
 * (to distinguish $$2 + \frac{1}{3}$$ from $$2 \cdot \frac{1}{3}$$ in $$2\tfrac{1}{3}$$).

The full specification of MathML entities is closely coordinated with the corresponding specifications for use with HTML and XML in general.

Thus, the expression a x^2+b x+c requires two layout elements: one to create the overall horizontal row and one for the superscripted exponent. However, the individual tokens also have to be identified as identifiers (), operators (), or numbers (). Adding the token markup, the full form ends up as

A complete document that consists of just the MathML example above, is shown here:

Content MathML
Content MathML focuses on the semantics, or meaning, of the expression rather than its layout. Central to Content MathML is the element that represents function application. The function being applied is the first child element under, and its operands or parameters are the remaining child elements. Content MathML uses only a few attributes.

Tokens such as identifiers and numbers are individually marked up, much as for Presentation MathML, but with elements such as  and . Rather than being merely another type of token, operators are represented by specific elements, whose mathematical semantics are known to MathML:, , etc. There are over a hundred different elements for different functions and operators.

For example, x represents $$\sin(x)$$ and x5</cn> represents $$x+5$$. The elements representing operators and functions are empty elements, because their operands are the other elements under the containing.

The expression $$a x^2+b x+c$$ could be represented as

Content MathML is nearly isomorphic to expressions in a functional language such as Scheme and other dialects of Lisp. ... amounts to Scheme's (...), and the many operator and function elements amount to Scheme functions. With this trivial literal transformation, plus un-tagging the individual tokens, the example above becomes: This reflects the long-known close relationship between XML element structures, and LISP or Scheme S-expressions.

Wikidata annotation in Content MathML
According to the OM Society, OpenMath Content Dictionaries can be employed as collections of symbols and identifiers with declarations of their semantics – names, descriptions and rules. A 2018 paper presented at the SIGIR conference proposed that the semantic knowledge base Wikidata could be used as an OpenMath Content Dictionary to link semantic elements of a mathematical formula to unique and language-independent Wikidata items.

Example
The well-known quadratic formula could be represented in Presentation MathML as an expression tree made up from layout elements like or :

This example uses the element, which can be used to embed a semantic annotation in non-XML format, for example to store the formula in the format used by an equation editor such as StarMath or the markup using LaTeX syntax. The encoding field is usually a MIME type, although most of the equation encodings don't have such a registration; freeform text may be used in such cases.

Although less compact than other formats, the XML structuring of MathML makes its content widely usable and accessible, allows near-instant display in applications such as web browsers, and facilitates an interpretation of its meaning in mathematical software products. MathML is not intended to be written or edited directly by humans.

Embedding MathML in HTML/XHTML files
MathML, being XML, can be embedded inside other XML files such as XHTML files using XML namespaces.

Inline MathML is also supported in HTML5 files. There is no need to specify namespaces as there was in XHTML.

Other standards
Another standard called OpenMath that has been more specifically designed (largely by the same people who devised Content MathML) for storing formulae semantically can be used to complement MathML. OpenMath data can be embedded in MathML using the <annotation-xml encoding="OpenMath"> element. OpenMath content dictionaries can be used to define the meaning of elements. The following would define P1(x) to be the first Legendre polynomial:

The OMDoc format has been created for markup of larger mathematical structures than formulae, from statements like definitions, theorems, proofs, and examples, to complete theories and even entire text books. Formulae in OMDoc documents can either be written in Content MathML or in OpenMath; for presentation, they are converted to Presentation MathML.

The ISO/IEC standard Office Open XML (OOXML) defines a different XML math syntax, derived from Microsoft Office products. However, it is partially compatible through XSL Transformations.

Specifications

 * W3C Recommendation: Mathematical Markup Language (MathML) 1.01 Specification
 * W3C Recommendation: Mathematical Markup Language (MathML) Version 2.0 (Second Edition)
 * W3C Recommendation: Mathematical Markup Language (MathML) Version 3.0 (Third Edition)

title: MathML


text:
Peter Waldo

Peter Waldo (c. 1140 – c. 1205; also Valdo, Valdes, Waldes; Pierre Vaudès, de Vaux, Petrus Waldus, Valdus) was the leader of the Waldensians, a Christian spiritual movement of the Middle Ages.

The tradition that his first name was "Peter" can only be traced back to the fourteenth century. This has caused some historians, such as Jana Schulman, to see it as likely a later invention. He is considered a Proto-Protestant.

Relationship with Waldenses
Peter Waldo is regarded by many historians, including Jana Schulman, as having founded the Waldensians sometime between 1170 and 1177.

There were claims that the Waldensians predated Peter Waldo. In his A History of the Vaudois Church (1859), Antoine Monastier quotes Bernard, Abbott of Foncald, writing at the end of the 12th century, that the Waldensians arose during the papacy of Lucius. Monastier takes him to mean Lucius II, Pope from 1144 to 1145, and concludes that the Waldenses were active before 1145. Bernard also says that the same Pope Lucius condemned them as heretics, but they were condemned by Pope Lucius III in 1184.

Monastier also says that Eberard de Béthune, writing in 1210 (although Monastier says 1160), claimed that the name Vaudois meant "valley dwellers" or those who "dwell in a vale of sorrow and tears", and was in use before Peter Waldo.

A claim persisted until the 19th century that Waldo had not begun any new movement but that he had arisen from a pure Christianity established by the Apostles in the Alps soon after Jesus' ascension, and that Waldo was merely perpetuating this pure faith.

Life and work
Most details of Waldo's life are unknown. Extant sources relate that he was a wealthy clothier and merchant from Lyon and a man of some learning. After establishing himself as a successful merchant, Waldo commissioned monks to create a translated copy of the Bible for him. The clerics from Lyon translated the New Testament into the vernacular "Romance" (Franco-Provençal). This has caused Waldo to be credited with providing to Europe the first translation of the Bible in a 'modern tongue' outside of Latin.

Through reading his Bible and writings of the Church Fathers, Waldo became fascinated with the concepts of purity and perfection. In 1173 in pursuit of purity, he embraced poverty after hearing an itinerant singer perform a song about Saint Alexius. Alexius had given up a large inheritance and a beautiful bride in order to live in poverty like Jesus. Waldo sold all he had, forswore his marriage and home, and put his two young daughters into a convent.

Waldo began traveling around Lombardy begging and preaching about the value of poverty. The region of Lombardy was a hotbed of religious reform movements at the time, many of which would be later deemed heresies by the Catholic Church. These include the Cathars, the Humiliati, the Albigensians, and the Speronists. As Waldo gathered followers and they determined their own doctrines they shared many features with these other reform movements - to the point that it becomes difficult for historians to determine the origins of many of the religious ideas circulating among them. Unlike the leaders of these other groups Waldo had never joined the Catholic Church's priesthood or any of its religious orders.

Other events, besides hearing of Saint Alexius, may have also contributed to Waldo's decision to take up poverty and preaching including a rejection of transubstantiation when it was considered a capital crime to do it, and the sudden and unexpected death of a friend during an evening meal. From this point onward he began living a radical Christian life, giving his property over to his wife, while the remainder of his belongings he distributed as alms to the poor. At about this time, Waldo began to preach and teach publicly, based on his ideas of simplicity and poverty, notably that "No man can serve two masters, God and Mammon."

Inspired by his example Waldo began to attract followers and they grew into a community of believers. By 1170 Waldo had gathered a large number of followers, referred to as the Poor of Lyons, the Poor of Lombardy, or the Poor of God. They evangelized their teaching while traveling as peddlers. Often referred to as the Waldensians (or Waldenses), they were distinct from the Albigensians or Cathari. The Waldensian movement was characterized from the beginning by lay preaching, voluntary poverty, and strict adherence to the Bible.

In January 1179, Waldo and one of his disciples went to Rome, where they were welcomed by Pope Alexander III and the Roman Curia. They had to explain their faith before a panel of three clergymen, including issues which were then debated within the Church, such as the universal priesthood, the gospel in the vulgate or local language, and the issue of voluntary poverty. The results of the meeting were inconclusive. The pope affirmed the Waldensians' vow of poverty, but forbade them to continue preaching due to their status as laypeople. Waldo and his followers revolted against the ban and increased their preaching and missionary efforts. They continued to gather followers and began proclaiming doctrines at odds with Catholicism - such as the right of all worthy members including women to preach the Scriptures without permission from Church authorities. They also began preaching against Purgatory, prayers for the dead, and indulgences. They were excommunicated by the Catholic Church. By the late 1180s, they were being pursued as heretics. This persecution only increased their preaching against the Roman Catholic Church. The Waldensians developed a doctrine that forbids the use of weapons or of oaths, which led them to refuse any participation in Catholic rituals. The Catholic hierarchy accused them of apostasy. Waldo condemned what he considered as papal excesses and Catholic dogmas, including purgatory and transubstantiation. He said that these dogmas were "the harlot" from the book of Revelation.

Waldo's ideas, but not the movement itself, were condemned at the Third Lateran Council in March of the same year. The leaders of the Waldensian movement were not yet excommunicated.

In 1180, Waldo composed a profession of faith which is still extant.

Driven away from Lyon, Waldo and his followers settled in the high valleys of Piedmont, and in France, in the Luberon, as they continued in their pursuit of Christianity based on the New Testament. Finally, Waldo was excommunicated by Pope Lucius III during the synod held at Verona in 1184. The doctrine of the Poor of Lyons was again condemned by the Fourth Lateran Council in 1215, when they mentioned the group by name for the first time, and declared its principles to be heresy. Fearing suppression from the Church, Waldo's followers fled to the mountainous regions of northern Italy in the Waldensian Evangelical Church.

title: Peter Waldo


text:
Mood disorder

A mood disorder, also known as an affective disorder, is any of a group of conditions of mental and behavioral disorder where a disturbance in the person's mood is the main underlying feature. The classification is in the Diagnostic and Statistical Manual of Mental Disorders (DSM) and International Classification of Diseases (ICD).

Mood disorders fall into seven groups, including; abnormally elevated mood, such as mania or hypomania; depressed mood, of which the best-known and most researched is major depressive disorder (MDD) (alternatively known as clinical depression, unipolar depression, or major depression); and moods which cycle between mania and depression, known as bipolar disorder (BD) (formerly known as manic depression). There are several sub-types of depressive disorders or psychiatric syndromes featuring less severe symptoms such as dysthymic disorder (similar to MDD, but longer lasting and more persistent, though often milder) and cyclothymic disorder (similar to but milder than BD).

In some cases, more than one mood disorder can be present in an individual, like bipolar disorder and depressive disorder. If a mood disorder and schizophrenia are both present in an individual, this is known as schizoaffective disorder. Mood disorders may also be substance induced, or occur in response to a medical condition.

English psychiatrist Henry Maudsley proposed an overarching category of affective disorder. The term was then replaced by mood disorder, as the latter term refers to the underlying or longitudinal emotional state, whereas the former refers to the external expression observed by others.

Depressive disorders

 * Major depressive disorder (MDD), commonly called major depression, unipolar depression, or clinical depression, wherein a person has one or more major depressive episodes. After a single episode, Major Depressive Disorder (single episode) would be diagnosed. After more than one episode, the diagnosis becomes Major Depressive Disorder (Recurrent). Depression without periods of mania is sometimes referred to as unipolar depression because the mood remains at the bottom "pole" and does not climb to the higher, manic "pole" as in bipolar disorder.

 * Individuals with a major depressive episode or major depressive disorder are at increased risk for suicide. Seeking help and treatment from a health professional dramatically reduces the individual's risk for suicide. Studies have demonstrated that asking if a depressed friend or family member has thought of committing suicide is an effective way of identifying those at risk, and it does not "plant" the idea or increase an individual's risk for suicide in any way. Epidemiological studies carried out in Europe suggest that, at this moment, roughly 8.5 percent of the world's population have a depressive disorder. No age group seems to be exempt from depression, and studies have found that depression appears in infants as young as 6 months old who have been separated from their mothers. However, there may be differences between cultures in prevalence of MDD due to cultural influences that "challenge the definition and diagnosis of psychiatric disorders", as seen in a study by Parker et al. that researched MDD in the Chinese. Depressive disorder (also known as depression) is a common mental disorder. It involves a depressed mood or loss of pleasure or interest in activities for long periods of time. Depression is different from regular mood changes and feelings about everyday life. It can affect all aspects of life. Depression can happen to anyone. People who have lived through abuse, severe losses, or other stressful events are more likely to develop depression.

 * Depressive disorder is frequent in primary care and general hospital practice but is often undetected. Unrecognized depressive disorder may slow recovery and worsen prognosis in physical illness, therefore it is important that all doctors be able to recognize the condition, treat the less severe cases, and identify those requiring specialist care.

 * Diagnosticians recognize several subtypes or course specifiers:

 * Atypical depression (AD) is characterized by mood reactivity (paradoxical anhedonia) and positivity, significant weight gain or increased appetite ("comfort eating"), excessive sleep or somnolence (hypersomnia), a sensation of heaviness in limbs known as leaden paralysis, and significant social impairment as a consequence of hypersensitivity to perceived interpersonal rejection. Difficulties in measuring this subtype have led to questions of its validity and prevalence.

 * Melancholic depression is characterized by a loss of pleasure (anhedonia) in most or all activities, a failure of reactivity to pleasurable stimuli, a quality of depressed mood more pronounced than that of grief or loss, a worsening of symptoms in the morning hours, early-morning waking, psychomotor retardation, excessive weight loss (not to be confused with anorexia nervosa), or excessive guilt.

 * Psychotic major depression (PMD), or simply psychotic depression, is the term for a major depressive episode, in particular of melancholic nature, wherein the patient experiences psychotic symptoms such as delusions or, less commonly, hallucinations. These are most commonly mood-congruent (content coincident with depressive themes).

 * Catatonic depression is a rare and severe form of major depression involving disturbances of motor behavior and other symptoms. Here, the person is mute and almost stuporous, and either is immobile or exhibits purposeless or even bizarre movements. Catatonic symptoms can also occur in schizophrenia or a manic episode, or can be due to neuroleptic malignant syndrome.

 * Postpartum depression (PPD) is listed as a course specifier in DSM-IV-TR; it refers to the intense, sustained and sometimes disabling depression experienced by women after giving birth. Postpartum depression, which affects 10–15% of women, typically sets in within three months of labor, and lasts as long as three months. It is quite common for women to experience a short-term feeling of tiredness and sadness in the first few weeks after giving birth; however, postpartum depression is different because it can cause significant hardship and impaired functioning at home, work, or school as well as, possibly, difficulty in relationships with family members, spouses, or friends, or even problems bonding with the newborn. In the treatment of postpartum major depressive disorders and other unipolar depressions in women who are breastfeeding, nortriptyline, paroxetine (Paxil), and sertraline (Zoloft) are in general considered to be the preferred medications. Women with personal or family histories of mood disorders are at particularly high risk of developing postpartum depression.

 * Premenstrual dysphoric disorder (PMDD) is a severe and disabling form of premenstrual syndrome affecting 3–8% of menstruating women. The disorder consists of a "cluster of affective, behavioral and somatic symptoms" that recur monthly during the luteal phase of the menstrual cycle. PMDD was added to the list of depressive disorders in the Diagnostic and Statistical Manual of Mental Disorders in 2013. The exact pathogenesis of the disorder is still unclear and is an active research topic. Treatment of PMDD relies largely on antidepressants that modulate serotonin levels in the brain via serotonin reuptake inhibitors as well as ovulation suppression using contraception.

 * Seasonal affective disorder (SAD), also known as "winter depression" or "winter blues", is a specifier. Some people have a seasonal pattern, with depressive episodes coming on in the autumn or winter, and resolving in spring. The diagnosis is made if at least two episodes have occurred in colder months with none at other times over a two-year period or longer. It is commonly hypothesised that people who live at higher latitudes tend to have less sunlight exposure in the winter and therefore experience higher rates of SAD, but the epidemiological support for this proposition is not strong (and latitude is not the only determinant of the amount of sunlight reaching the eyes in winter). It is said that this disorder can be treated by light therapy. SAD is also more prevalent in people who are younger and typically affects more females than males.

 * Dysthymia is a condition related to unipolar depression, where the same physical and cognitive problems are evident, but they are not as severe and tend to last longer (usually at least 2 years). The treatment of dysthymia is largely the same as for major depression, including antidepressant medications and psychotherapy.

 * Double depression can be defined as a fairly depressed mood (dysthymia) that lasts for at least two years and is punctuated by periods of major depression.

 * Unspecified Depressive Disorder is designated by the code 311 for depressive disorders. In the DSM-5, Unspecified Depressive Disorder encompasses symptoms that are characteristic of depressive disorders and cause significant impairment in functioning, but do not meet the criteria for the diagnosis of any specified depressive disorders. In the DSM-IV, this was called Depressive Disorder Not Otherwise Specified.

 * Depressive personality disorder (DPD) is a controversial psychiatric diagnosis that denotes a personality disorder with depressive features. Originally included in the DSM-II, depressive personality disorder was removed from the DSM-III and DSM-III-R. Recently, it has been reconsidered for reinstatement as a diagnosis. Depressive personality disorder is currently described in Appendix B in the DSM-IV-TR as worthy of further study.

 * Recurrent brief depression (RBD), distinguished from major depressive disorder primarily by differences in duration. People with RBD have depressive episodes about once per month, with individual episodes lasting less than two weeks and typically less than 2–3 days. Diagnosis of RBD requires that the episodes occur over the span of at least one year and, in female patients, independently of the menstrual cycle. People with clinical depression can develop RBD, and vice versa and both illnesses have similar risks.

 * Minor depressive disorder, or simply minor depression, which refers to a depression that does not meet full criteria for major depression but in which at least two symptoms are present for two weeks.

Bipolar disorders

 * Bipolar disorder (BD) (also called "manic depression" or "manic-depressive disorder"), an unstable emotional condition characterized by cycles of abnormal, persistent high mood (mania) and low mood (depression), which was formerly known as "manic depression" (and in some cases rapid cycling, mixed states, and psychotic symptoms). Subtypes include:

 * Bipolar I is distinguished by the presence or history of one or more manic episodes or mixed episodes with or without major depressive episodes. A depressive episode is not required for the diagnosis of Bipolar I Disorder, but depressive episodes are usually part of the course of the illness.
 * Bipolar II consisting of recurrent intermittent hypomanic and depressive episodes or mixed episodes.
 * Cyclothymia is a form of bipolar disorder, consisting of recurrent hypomanic and dysthymic episodes, but no full manic episodes or full major depressive episodes.
 * Bipolar disorder not otherwise specified (BD-NOS), sometimes called "sub-threshold" bipolar, indicates that the patient has some symptoms in the bipolar spectrum (e.g., manic and depressive symptoms) but does not fully qualify for any of the three formal bipolar DSM-IV diagnoses mentioned above.
 * It is estimated that roughly 1% of the adult population has bipolar I, a further 1% has bipolar II or cyclothymia, and somewhere between 2% and 5% percent have "sub-threshold" forms of bipolar disorder. Furthermore, the possibility of getting bipolar disorder when one parent is diagnosed with it is 15–30%. Risk, when both parents have it, is 50–75%. Also, while with bipolar siblings the risk is 15–25%, with identical twins it is about 70%.

Substance-induced
A mood disorder can be classified as substance-induced if its etiology can be traced to the direct physiologic effects of a psychoactive drug or other chemical substance, or if the development of the mood disorder occurred contemporaneously with substance intoxication or withdrawal. Also, an individual may have a mood disorder coexisting with a substance abuse disorder. Substance-induced mood disorders can have features of a manic, hypomanic, mixed, or depressive episode. Most substances can induce a variety of mood disorders. For example, stimulants such as amphetamine, methamphetamine, and cocaine can cause manic, hypomanic, mixed, and depressive episodes.

Alcohol-induced
High rates of major depressive disorder occur in heavy drinkers and those with alcoholism. Controversy has previously surrounded whether those who abused alcohol and developed depression were self-medicating their pre-existing depression. Recent research has concluded that, while this may be true in some cases, alcohol misuse directly causes the development of depression in a significant number of heavy drinkers. Participants studied were also assessed during stressful events in their lives and measured on a Feeling Bad Scale. Likewise, they were also assessed on their affiliation with  deviant  peers, unemployment, and their partner's substance use and criminal offending. High rates of suicide also occur in those who have alcohol-related problems. It is usually possible to differentiate between alcohol-related depression and depression that is not related to alcohol intake by taking a careful history of the patient. Depression and other mental health problems associated with alcohol misuse may be due to distortion of brain chemistry, as they tend to improve on their own after a period of abstinence.

Benzodiazepine-induced
Benzodiazepines, such as alprazolam, clonazepam, lorazepam and diazepam, can cause both depression and mania.

Benzodiazepines are a class of medication commonly used to treat anxiety, panic attacks and insomnia, and are also commonly misused and abused. Those with anxiety, panic and sleep problems commonly have negative emotions and thoughts, depression, suicidal ideations, and often have comorbid depressive disorders. While the anxiolytic and hypnotic effects of benzodiazepines may disappear as tolerance develops, depression and impulsivity with high suicidal risk commonly persist. These symptoms are "often interpreted as an exacerbation or as a natural evolution of previous disorders and the chronic use of sedatives is overlooked". Benzodiazepines do not prevent the development of depression, can exacerbate preexisting depression, can cause depression in those with no history of it, and can lead to suicide attempts. Risk factors for suicide and suicide attempts while using benzodiazepines include high dose prescriptions (even in those not misusing the medications), benzodiazepine intoxication, and underlying depression.

The long-term use of benzodiazepines may have a similar effect on the brain as alcohol, and are also implicated in depression. As with alcohol, the effects of benzodiazepine on neurochemistry, such as decreased levels of serotonin and norepinephrine, are believed to be responsible for the increased depression. Additionally, benzodiazepines can indirectly worsen mood by worsening sleep (i.e., benzodiazepine-induced sleep disorder). Like alcohol, benzodiazepines can put people to sleep but, while asleep, they disrupt sleep architecture: decreasing sleep time, delaying time to REM sleep, and decreasing deep sleep (the most restorative part of sleep for both energy and mood). Just as some antidepressants can cause or worsen anxiety in some patients due to being activating, benzodiazepines can cause or worsen depression due to being a central nervous system depressant—worsening thinking, concentration and problem solving (i.e., benzodiazepine-induced neurocognitive disorder). However, unlike antidepressants, in which the activating effects usually improve with continued treatment, benzodiazepine-induced depression is unlikely to improve until after stopping the medication.

In a long-term follow-up study of patients dependent on benzodiazepines, it was found that 10 people (20%) had taken drug overdoses while on chronic benzodiazepine medication despite only two people ever having had any pre-existing depressive disorder. A year after a gradual withdrawal program, no patients had taken any further overdoses.

Just as with intoxication and chronic use, benzodiazepine withdrawal can also cause depression. While benzodiazepine-induced depressive disorder may be exacerbated immediately after discontinuation of benzodiazepines, evidence suggests that mood significantly improves after the acute withdrawal period to levels better than during use. Depression resulting from withdrawal from benzodiazepines usually subsides after a few months but in some cases may persist for 6–12 months.

Due to another medical condition
"Mood disorder due to a general medical condition" is used to describe manic or depressive episodes which occur secondary to a medical condition. There are many medical conditions that can trigger mood episodes, including neurological disorders (e.g. dementias), hearing loss and associated disorders (e.g. tinnitus or hyperacusis), metabolic disorders (e.g. electrolyte disturbances), gastrointestinal diseases (e.g. cirrhosis), endocrine disease (e.g. thyroid abnormalities), cardiovascular disease (e.g. heart attack), pulmonary disease (e.g. chronic obstructive pulmonary disease), cancer, autoimmune diseases (e.g. multiple sclerosis), and pregnancy.

Not otherwise specified
Mood disorder not otherwise specified (MD-NOS) is a mood disorder that is impairing but does not fit in with any of the other officially specified diagnoses. In the DSM-IV MD-NOS is described as "any mood disorder that does not meet the criteria for a specific disorder." MD-NOS is not used as a clinical description but as a statistical concept for filing purposes. The diagnosis of MD-NOS does not exist in the DSM-5, however the diagnoses of unspecified depressive disorder and unspecified bipolar disorder are in the DSM-5.

Most cases of MD-NOS represent hybrids between mood and anxiety disorders, such as mixed anxiety-depressive disorder or atypical depression. An example of an instance of MD-NOS is being in minor depression frequently during various intervals, such as once every month or once in three days. There is a risk for MD-NOS not to get noticed, and for that reason not to get treated.

Causes
Meta-analyses show that high scores on the personality domain neuroticism are a strong predictor for the development of mood disorders. A number of authors have also suggested that mood disorders are an evolutionary adaptation (see also evolutionary psychiatry). A low or depressed mood can increase an individual's ability to cope with situations in which the effort to pursue a major goal could result in danger, loss, or wasted effort. In such situations, low motivation may give an advantage by inhibiting certain actions. This theory helps to explain why negative life incidents precede depression in around 80 percent of cases, and why they so often strike people during their peak reproductive years. These characteristics would be difficult to understand if depression were a dysfunction.

A depressed mood is a predictable response to certain types of life occurrences, such as loss of status, divorce, or death of a child or spouse. These are events that signal a loss of reproductive ability or potential, or that did so in humans' ancestral environment. A depressed mood can be seen as an adaptive response, in the sense that it causes an individual to turn away from the earlier (and reproductively unsuccessful) modes of behavior.

A depressed mood is common during illnesses, such as influenza. It has been argued that this is an evolved mechanism that assists the individual in recovering by limiting their physical activity. The occurrence of low-level depression during the winter months, or seasonal affective disorder, may have been adaptive in the past, by limiting physical activity at times when food was scarce. It is argued that humans have retained the instinct to experience low mood during the winter months, even if the availability of food is no longer determined by the weather.

Much of what is known about the genetic influence of clinical depression is based upon research that has been done with identical twins. Identical twins have exactly the same genetic code. It has been found that when one identical twin becomes depressed the other will also develop clinical depression approximately 76% of the time. When identical twins are raised apart from each other, they will both become depressed about 67% of the time. Because both twins become depressed at such a high rate, the implication is that there is a strong genetic influence. If it happened that when one twin becomes clinically depressed the other always develops depression, then clinical depression would likely be entirely genetic.

Bipolar disorder is also considered a mood disorder and it is hypothesized that it might be caused by mitochondrial dysfunction.

Sex differences
Mood disorders, specifically stress-related mood disorders such as anxiety and depression, have been shown to have differing rates of diagnosis based on sex. In the United States, women are two times more likely than men to be diagnosed with a stress-related mood disorder. Underlying these sex differences, studies have shown a dysregulation of stress-responsive neuroendocrine function causing an increase in the likelihood of developing these affective disorders. Overactivation of the hypothalamic-pituitary-adrenal (HPA) axis could provide potential insight into how these sex differences arise. Neuropeptide corticotropin-releasing factor (CRF) is released from the paraventricular nucleus (PVN) of the hypothalamus, stimulating adrenocorticotropic hormone (ACTH) release into the blood stream. From here ACTH triggers the release of glucocorticoids such as cortisol from the adrenal cortex. Cortisol, known as the main stress hormone, creates a negative feedback loop back to the hypothalamus to deactivate the stress response. When a constant stressor is present, the HPA axis remains overactivated and cortisol is constantly produced. This chronic stress is associated with sustained CRF release, resulting in the increased production of anxiety- and depressive-like behaviors and serving as a potential mechanism for differences in prevalence between men and women.

DSM-5
The DSM-5, released in May 2013, separates the mood disorder chapter from the DSM-IV-TR into two sections: Depressive and related disorders and bipolar and related disorders. Bipolar disorders fall in between depressive disorders and schizophrenia spectrum and related disorders "in recognition of their place as a bridge between the two diagnostic classes in terms of symptomatology, family history and genetics" (Ref. 1, p 123). Bipolar disorders underwent a few changes in the DSM-5, most notably the addition of more specific symptomology related to hypomanic and mixed manic states. Depressive disorders underwent the most changes, the addition of three new disorders: disruptive mood dysregulation disorder, persistent depressive disorder (previously dysthymia), and premenstrual dysphoric disorder (previously in appendix B, the section for disorders needing further research). Disruptive mood dysregulation disorder is meant as a diagnosis for children and adolescents who would normally be diagnosed with bipolar disorder as a way to limit the bipolar diagnosis in this age cohort. Major depressive disorder (MDD) also underwent a notable change, in that the bereavement clause has been removed. Those previously exempt from a diagnosis of MDD due to bereavement are now candidates for the MDD diagnosis.

Treatment
There are different types of treatments available for mood disorders, such as therapy and medications. Behaviour therapy, cognitive behaviour therapy and interpersonal therapy have all shown to be potentially beneficial in depression. Major depressive disorder medications usually include antidepressants; a combination of antidepressants and cognitive behavioral therapy has shown to be more effective than one treatment alone. Bipolar disorder medications can consist of antipsychotics, mood stabilizers, anticonvulsants and/or lithium. Lithium specifically has been proven to reduce suicide and all causes of mortality in people with mood disorders. If mitochondrial dysfunction or mitochondrial diseases are the cause of mood disorders like bipolar disorder, then it has been hypothesized that N-acetyl-cysteine (NAC), acetyl-L-carnitine (ALCAR), S-adenosylmethionine (SAMe), coenzyme Q10 (CoQ10), alpha-lipoic acid (ALA), creatine monohydrate (CM), and melatonin could be potential treatment options. In determining treatment, there are many types of depression scales that are used. One of the depression scales is a self-report scale called Beck Depression Inventory (BDI). Another scale is the Hamilton Depression Rating Scale (HAMD). HAMD is a clinical rating scale in which the patient is rated based on clinician observation. The Center for Epidemiologic Studies Depression Scale (CES-D) is a scale for depression symptoms that applies to the general population. This scale is typically used in research and not for self-reports. The PHQ-9 which stands for Patient-Health Questionnaire-9 questions, is a self-report as well. Finally, the Mood Disorder Questionnaire (MDQ) evaluates bipolar disorder.

Epidemiology
According to a substantial number of epidemiology studies conducted, women are twice as likely to develop certain mood disorders, such as major depression. Although there is an equal number of men and women diagnosed with bipolar II disorder, women have a slightly higher frequency of the disorder.

In 2011, mood disorders were the most common reason for hospitalization among children aged 1–17 years in the United States, with approximately 112,000 stays. Mood disorders were top principal diagnosis for Medicaid super-utilizers in the United States in 2012. Further, a study of 18 states found that mood disorders accounted for the highest number of hospital readmissions among Medicaid patients and the uninsured, with 41,600 Medicaid patients and 12,200 uninsured patients being readmitted within 30 days of their index stay—a readmission rate of 19.8 per 100 admissions and 12.7 per 100 admissions, respectively. In 2012, mood and other behavioral health disorders were the most common diagnoses for Medicaid-covered and uninsured hospital stays in the United States (6.1% of Medicaid stays and 5.2% of uninsured stays).

A study conducted in 1988 to 1994 amongst young American adults involved a selection of demographic and health characteristics. A population-based sample of 8,602 men and women ages 17–39 years participated. Lifetime prevalence were estimated based on six mood measures:
 * major depressive episode (MDE) 8.6%,
 * major depressive disorder with severity (MDE-s) 7.7%,
 * dysthymia 6.2%,
 * MDE-s with dysthymia 3.4%,
 * any bipolar disorder 1.6%, and
 * any mood disorder 11.5%.

Research
Kay Redfield Jamison and others have explored the possible links between mood disorders – especially bipolar disorder – and creativity. It has been proposed that a "ruminating personality type may contribute to both [mood disorders] and art."

Jane Collingwood notes an Oregon State University study that:"looked at the occupational status of a large group of typical patients and found that 'those with bipolar illness appear to be disproportionately concentrated in the most creative occupational category.' They also found that the likelihood of 'engaging in creative activities on the job' is significantly higher for bipolar than nonbipolar workers."In Liz Paterek's article "Bipolar Disorder and the Creative Mind" she wrote:"Memory and creativity are related to mania. Clinical studies have shown that those in a manic state will rhyme, find synonyms, and use alliteration more than controls. This mental fluidity could contribute to an increase in creativity. Moreover, mania creates increases in productivity and energy. Those in a manic state are more emotionally sensitive and show less inhibition about attitudes, which could create greater expression. Studies performed at Harvard looked into the amount of original thinking in solving creative tasks. Bipolar individuals, whose disorder was not severe, tended to show greater degrees of creativity."The relationship between depression and creativity appears to be especially strong among poets.

title: Mood disorder


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Talk:Prince Albert (genital piercing)

Image placement
In case you missed the notice above, much discussion has gone into the use and type of images in this article, as well as their placement. Moving, resizing or deleting the images in this article is considered vandalism and all such changes will be reverted. Please see the archived discussions for details: Archive 1 Archive 2. Jokestress (talk) 01:43, 3 July 2011 (UTC)

I WOULD SUGGEST THAT THEY BE PLACED ELSEWHERE OUR UNDER AGE VERIFICATION! MY 12 YEAR OLD SON LED ME TO THIS ARTICLE THINKING IT WAS FUNNY. HE THEN TOOK ME ON A TOUR OF SEVERAL OTHER GOODIES THAT ARE OF NAKED PEOPLE. THIS IS PORN! THERE NEEDS TO BE USER LOGIN AND PASSWORD INFORMATION AND PROOF OF AGE. NOT SAYING THE INFORMATION IS INAPPROPRIATE FOR ALL AGES - BUT UNDER 18 THERE NEEDS TO BE A RESTRICTION. DOES NOBODY MONITOR THE TYPES OF PICS AND THINGS ARE POSTED? AS A PARENT IT GREATLY ANGERS AND CONCERNS ME.WIKIPEDIA IS SUCH A WONDERFUL TOOL FOR LEARNING. BUT IF IT CAN'T BE CONTROLLED AND REGULATED THEN IT NEEDS TO BE SHUT DOWN. AS OF NOW MY SON'S COMPUTER HAS WIKIPEDIA BLOCKED AND i PLAN TO TALK TO THE SCHOOL BOARD ABOUT THIS AS WELL.

ALL THAT REALLY NEEDS TO BE SAID TO THE CHILD IS THAT A P.A. IS A PIERCING OF THE PENIS - THE END. THE PARENT CAN DECIDE IF THEY WISH TO ELABORATE TO THE CHILD.

And you my friend have way too much time on your hands! — Preceding unsigned comment added by 79.77.76.157 (talk) 20:42, 2 January 2018 (UTC)

 * Wikipedia is not censored. That means relevant images will be included and we do not hide them. Period. If you don't want your child to see images of a pierced penis on an article about pierced penises, you should be monitoring their Internet usage more closely. Babysitting your kid is not our job. ICY TIGER'S BLOOD  19:24, 12 February 2013 (UTC)

Hatnote
Because this is frequently the top search engine result for "Prince Albert," even though the primary here is Prince Albert, I believe WP:HATNOTE allows for a notation to otheruses. Jokestress (talk) 22:22, 11 April 2012 (UTC)

Google
Still the top search result on Google for Prince Albert, people are using this as an example of "Wiki-porn"... How notable or wide-spread is this type of piercing? If it isn't, maybe you could somehow merge it with other genital piercings? Ikmxx (talk) 04:42, 19 June 2013 (UTC)

Nevermind... after researching it a bit, I think the article is just fine how it is, but how it ended up top is a different problem, it's due people linking to it more than the other one so it's nothing that can be fixed, more of a problem on Google's end... Ikmxx (talk) 05:36, 19 June 2013 (UTC)

main page image
The main page image on the article is laughably un-encyclopedic. It looks like the kind of unsolicited dick pic you'd get from a sketchy online hookup. It's blurry, dark, poorly framed and obviously taken by the subject himself. There are two other images in the article which are both better illustrations, so this image serves no purpose and should be removed. WP:CENSOR does not apply here, but WP:GRATUITOUS does. 24.91.28.20 (talk) 04:31, 13 May 2015 (UTC)

 * Article has been updated (including better images). — 78.149.199.229 (talk) 21:36, 24 August 2015 (UTC)

Suggest at least a couple more pictures of normal PA piercings.
The discussions about images/illustrations is outrageous. Parents need to be aware of what their children are doing on the internet. Wikipedia is used for information regarding specific subjects. If a person can't find the information they require they will need a new source.

I'm trying to find more pictures of "normal" PA piercings. I have questions regarding what a blowout might look like. Surprisingly enough it is hard to find pictures of this. You find more of the "worst case scenario" pictures or outrageously sized piercings. On my new piercing I am concerned I may be getting a blowout, but what I have looks no where near the only pictures I find. But I am having a hard time finding pictures of a normal piercing (not outrageously sized!) with high enough definition to see skin close up.

I thought I might be able to find standard pictures here but instead I see people complaining that they accidentally clicked on the page. Here's an idea. Don't click on the "Prince Albert (GENITAL PIERCING)" link if you don't want to see it! — Preceding unsigned comment added by JTH1124 (talk • contribs) 21:17, 12 May 2017 (UTC)

External links modified
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Hooooly guacamole
Why not include some pictures of more mild PA piercings? Mother of God, this is the most cringeworthy article on wikipedia. To pass these extreme versions of piercings as the norm is ignorance at best, deception at worst... Please include the more mild/common versions of the piercings in the picture that are first seen rather than the butchery of what has become. Thank you, please understand that I have good intentions and that I just want readers to be aware of all of the differences that make us human. I love us all and I think that we need to be appropriate and impartial to what constitutes a PA piercing. This is all I will be saying on the subject. Judging from previous replies from the mods, they do not care about these sort of concerns. But, I will vocalize my own concern as one of perhaps hundreds that disagree with the choice of pictures being used. Furthermore I believe that I have a very reasonable complaint that is common in anyone who views this page. Again, I will not be replying nor will I read any replies to this comment. What I said is fact, and that is objectively true. Fefil14 (talk) 08:59, 5 November 2019 (UTC)

Image is not a Prince Albert
The picture captioned Prince Albert piercing plus scrotal ladder of BCRs, pubic piercing and tattoo does not show a penis with a Prince Albert piercing. Come to think of it, it doesn't show either a scrotal ladder or a tattoo. It does show an apparently erect penis, with helpful signposts to the various penile parts; but a piercing, no.

I sometimes wonder if editors mischievously substitute pictures which are deliberately wrong, to prove that no-one actually reads these articles; or, if readers do, they do not possess sufficient critical faculties to question what they see. Nuttyskin (talk) 12:31, 23 July 2023 (UTC)

title: Talk:Prince Albert (genital piercing)


text:
Representative democracy

Representative democracy (also called electoral democracy or indirect democracy) is a type of democracy where representatives are elected by the public. Nearly all modern Western-style democracies function as some type of representative democracy: for example, the United Kingdom (a unitary parliamentary constitutional monarchy), Germany (a federal parliamentary republic), France (a unitary semi-presidential republic), and the United States (a federal presidential republic). This is different from direct democracy, where the public votes directly on laws or policies, rather than representatives.

Political parties often become prominent in representative democracy if electoral systems require or encourage voters to vote for political parties or for candidates associated with political parties (as opposed to voting for individual representatives). Some political theorists (including Robert Dahl, Gregory Houston, and Ian Liebenberg) have described representative democracy as polyarchy.

Representative democracy can be organized in different ways including both parliamentary and presidential systems of government. Elected representatives typically form a legislature (such as a parliament or congress), which may be composed of a single chamber (unicameral), two chambers (bicameral), or more than two chambers (multicameral). Where two or more chambers exist, their members are often elected in different ways. The power of representatives is usually curtailed by a constitution (as in a constitutional democracy or a constitutional monarchy) or other measures to balance representative power:

 * An independent judiciary, which may have the power to declare legislative acts unconstitutional (e.g. constitutional court, supreme court).
 * The constitution may also provide for some deliberative democracy (e.g., Royal Commissions) or direct popular measures (e.g., initiative, referendum, recall elections). However, these are not always binding and usually require some legislative action—legal power usually remains firmly with representatives.
 * In some cases, a bicameral legislature may have an "upper house" that is not directly elected, such as the Senate of Canada, which was in turn modeled on the British House of Lords.

Some political theorists, such as Edmund Burke, believe that part of the duty of a representative is not simply to follow the wishes of the electorate but also to use their own judgment in the exercise of their powers, even if their views are not reflective of those of a majority of voters. A representative who chooses to execute the wishes of his or her constituents acts as a delegate. If the representative chooses to use his or her best judgment and knowledge in making decisions, even when the constituents do not fully agree with the decision, then the representative acts as a trustee.

History
The Roman Republic was the first known state in the Western world to have a representative government, despite taking the form of a direct government in the Roman assemblies. The Roman model of governance would inspire many political thinkers over the centuries, and today's modern representative democracies imitate more the Roman than the Greek model, because it was a state in which supreme power was held by the people and their elected representatives, and which had an elected or nominated leader. Representative democracy is a form of democracy in which people vote for representatives who then vote on policy initiatives; as opposed to direct democracy, a form of democracy in which people vote on policy initiatives directly. A European medieval tradition of selecting representatives from the various estates (classes, but not as we know them today) to advise/control monarchs led to relatively wide familiarity with representative systems inspired by Roman systems.

In Britain, Simon de Montfort is remembered as one of the fathers of representative government for holding two famous parliaments. The first, in 1258, stripped the king of unlimited authority and the second, in 1265, included ordinary citizens from the towns. Later, in the 17th century, the Parliament of England implemented some of the ideas and systems of liberal democracy, culminating in the Glorious Revolution and passage of the Bill of Rights 1689. Widening of the voting franchise took place through a series of Reform Acts in the 19th and 20th centuries.

The American Revolution led to the creation of a new Constitution of the United States in 1787, with a national legislature based partly on direct elections of representatives every two years, and thus responsible to the electorate for continuance in office. Senators were not directly elected by the people until the adoption of the Seventeenth Amendment in 1913. Women, men who owned no property, and Black people, and others not originally given voting rights, in most states eventually gained the vote through changes in state and federal law in the course of the 19th and 20th centuries. Until it was repealed by the Fourteenth Amendment following the Civil War, the Three-Fifths Compromise gave a disproportionate representation of slave states in the House of Representatives relative to the voters in free states.

In 1789, Revolutionary France adopted the Declaration of the Rights of Man and of the Citizen and, although short-lived, the National Convention was elected by all males in 1792. Universal male suffrage was re-established in France in the wake of the French Revolution of 1848.

Representative democracy came into general favour particularly in post-industrial revolution nation states where large numbers of citizens evinced interest in politics, but where technology and population figures remained unsuited to direct democracy. Many historians credit the Reform Act 1832 with launching modern representative democracy in the United Kingdom. Globally, a majority of governments in the world are representative democracies, including constitutional monarchies and republics with strong representative branches.

Research on representation democracy
Separate but related, and very large, bodies of research in political philosophy and social science investigate how and how well elected representatives, such as legislators, represent the interests or preferences of one or another constituency. The empirical research shows that representative systems tend to be biased towards the representation of more affluent classes to the detriment of the population at large.

Criticisms
In his book Political Parties, written in 1911, Robert Michels argues that most representative systems deteriorate towards an oligarchy or particracy. This is known as the iron law of oligarchy. Representative democracies which are stable have been analysed by Adolf Gasser and compared to the unstable representative democracies in his book Gemeindefreiheit als Rettung Europas which was published in 1943 and a second edition in 1947. Adolf Gasser stated the following requirements for a representative democracy in order to remain stable, unaffected by the iron law of oligarchy:
 * Society has to be built up from bottom to top. As a consequence, society is built up by people, who are free and have the power to defend themselves with weapons.
 * These free people join or form local communities. These local communities are independent, which includes financial independence, and they are free to determine their own rules.
 * Local communities join into a higher unit, e.g. a canton.
 * There is no hierarchical bureaucracy.
 * There is competition between these local communities, e.g. on services delivered or on taxes.

A drawback to this type of government is that elected officials are not required to fulfill promises made before their election and are able to promote their own self-interests once elected, providing an incohesive system of governance. Legislators are also under scrutiny as the system of majority-won legislators voting for issues for the large group of people fosters inequality among the marginalized.

Proponents of direct democracy criticize representative democracy due to its inherent structure. As the fundamental basis of representative democracy is non inclusive system, in which representatives turn into an elite class that works behind closed doors, as well as the criticizing the elector system as being driven by a capitalistic and authoritarian system.

Proposed solutions
The system of stochocracy has been proposed as an improved system compared to the system of representative democracy, where representatives are elected. Stochocracy aims to at least reduce this degradation by having all representatives appointed by lottery instead of by voting. Therefore, this system is also called lottocracy. The system was proposed by the writer Roger de Sizif in 1998 in his book La Stochocratie. Choosing officeholders by lot was also the standard practice in ancient Athenian democracy and in ancient India. The rationale behind this practice was to avoid lobbying and electioneering by economic oligarchs.

The system of deliberative democracy is a mix between a majority-ruled system and a consensus-based system. It allows for representative democracies or direct democracies to coexist with its system of governance, providing an initial advantage.

title: Representative democracy