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Government of Åland

The Landskapsregering is the government of Åland, an autonomous region of Finland. The government is led by a Lantråd, the premier of Åland, who is elected by the Lagting, the parliament of Åland.

Government
Government member parties since 2023: Liberals for Åland, Åland Centre Party and the Åland Social Democrats.

2015 to 2019
Government member parties: Liberals for Åland (Lib), Åland Social Democrats (S) and Moderate Coalition for Åland (M):

 * Premier:
 * Katrin Sjögren (Lib)
 * Deputy Premier, Minister of Industry, Trade and Environment:
 * Camilla Gunell (S)
 * Minister for Finance:
 * Mats Perämaa (Lib)
 * Minister of Education and Culture:
 * Tony Asumaa (Lib)
 * Minister of Administration and EU-affairs:
 * Nina Fellman (S)
 * Minister of Health and Social Affairs:
 * Wille Valve (M)
 * Minister of Communications and Infrastructure:
 * Mika Nordberg (M)

2011 to 2015
Government member parties: Åland Social Democrats (S), Åland Centre Party (C), Non-aligned Coalition (Obs) and Moderate Coalition for Åland (M):

 * Premier:
 * Camilla Gunell (S)
 * Deputy Premier, Minister of Finance:
 * Roger Nordlund (C)
 * Minister of Education and Culture:
 * Johan Ehn (M)
 * Minister of Social Affairs and Environment:
 * Carina Aaltonen (S)
 * Minister of Administration and EU-affairs:
 * Gun-Mari Lindholm (Obs)
 * Minister of Industry and Trade:
 * Fredrik Karlström (Obs)
 * Minister of Communications and Infrastructure:
 * Veronica Thörnroos (C)

2007 to 2011
Government member parties: Liberals for Åland (Lib) and Åland Centre Party (C):

 * Premier:
 * Viveka Eriksson (Lib)
 * Deputy Premier, Minister of Education and Culture:
 * Britt Lundberg (C)
 * Minister for Finance:
 * Mats Perämaa (Lib)
 * Minister of Social Affairs and Environment:
 * Katrin Sjögren (Lib)
 * Minister of Administration and EU-affairs:
 * Roger Eriksson (Lib)
 * Minister of Industry and Trade:
 * Jan-Erik Mattsson (C)
 * Minister of Communications:
 * Runar Karlsson (C) 2007 to 2009
 * Veronica Thörnroos (C) 2009 to 2011

2005 to 2007
Government members 2005–2007, Åland Centre Party (C), Åland Conservatives (Fs), Åland Social Democrats (S):

 * Premier:
 * Mr. Roger Nordlund (C)
 * Deputy Premier, Minister of Industry and Trade:
 * Mr. Jörgen Strand (Fs)
 * Minister of Equality and EU Affairs:
 * Mrs. Britt Lundberg (C)
 * Minister of Social Affairs and Environment:
 * Mrs. Harriet Lindeman (Fs)
 * Minister of Education and Culture:
 * Mrs. Camilla Gunell (S)
 * Minister for Finance:
 * Mr. Lasse Wiklöf (S)
 * Minister of Communications:
 * Mr. Runar Karlsson (C)

2003 to 2004
Government members 2003–2004, Åland Centre Party (C), Åland conservatives (Fs), Liberals for Åland (Lib), Non-aligned Coalition (Obs):

 * Premier:
 * Mr. Roger Nordlund (C)
 * Deputy Premier, Minister for Finance:
 * Mr. Jörgen Strand (Fs)
 * Minister of Social Affairs and Environment:
 * Mrs. Gun-Mari Lindholm (Obs)
 * Minister of Education and Culture:
 * Mr. Lars Selander (Lib)
 * Minister of Industry and Trade:
 * Mrs. Kerstin Alm (C)
 * Minister of Transportation and Police:
 * Mrs. Tuula Mattsson (Lib)

2001 to 2003
Government members 2001–2003, Åland Centre Party (C), Liberals for Åland (Lib)

Premier: Deputy Premier, Minister for Finance: Minister of Social Affairs and Environment: Minister of Education and Culture: Minister of Industry and Trade: Minister of Transportation and Energy:
 * Mr. Roger Nordlund (C)
 * Mr. Olof Erland (Lib)
 * Mr. Sune Eriksson (Lib)
 * Mrs. Gun Carlson (C)
 * Mrs. Ritva Sarin-Grufberg (Lib)
 * Mr. Runar Karlsson (c)

1999 to 2001
Government members 1999–2001, Åland Centre Party (C), Åland Conservatives (fs), Non-aligned Coalition (Obs):

Premier: Deputy premier, Minister for Finance: Minister of Social Affairs and Environment: Minister of Education and Culture: Minister of Industry and Trade: Minister of Transportation and Energy: Minister of Information Technology and Law Affairs:
 * Mr. Roger Nordlund (C)
 * Mr. Olof Salmén (Obs)
 * Mrs. Harriet Lindeman (Fs)
 * Mrs. Gun Carlson (C)
 * Mr. Roger Jansson (Fs)
 * Mr. Runar Karlsson (C)
 * Mr. Danne Sundman (Obs)

title: Government of Åland


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Upanayana

Upanayana (उपनयन) is a Hindu educational sacrament, one of the traditional saṃskāras or rites of passage that marked the acceptance of a student by a preceptor, such as a guru or acharya, and an individual's initiation into a school in Hinduism. Some traditions consider the ceremony as a spiritual rebirth for the child or future dvija, twice born. It signifies the acquisition of the knowledge of and the start of a new and disciplined life as a brahmacharya. According to the given community and its regional language, it is also known by numerous terms such as mekhal in Kashmiri (मेखल), janeo in Punjabi (ਜਨੇੇਓ), jaanoi in Gujrati (જાનોઇ), janya in Sindhi (जन्य), janev in Bhojpuri (जनेव), munja in Marathi (मुंजा), munji in Konkani (मुंजी), poite in Bangla (পৈতৈ), brataghara in Odia (ବ୍ରତଘର), logun dioni in Assamese (লগুণ দিওনী), bratabandha in Nepali (ब्रतबन्ध), chewar in Newari (छेवार), upanayana in Kannada (ಉಪನಯನ), upanayanamu in Telugu (ఉపనయనము), upanayanam in Malayalam (ഉപനയനമ്), and upanayanam or poonool in Tamil (உபநயனம் or பூணூல்).  The Upanayanam ceremony is arguably the most important rite for Brahmin, Kshatriya, and Vaishya males, ensuring his rights with responsibilities and signifying his advent into adulthood''. ''

The tradition is widely discussed in ancient Sanskrit texts of Hinduism and varies regionally. The sacred thread or yajnopavita (also referred to as Janeu, Jandhyam, Poonul, Munja and Janivara Yonya ) has become one of the most important identifiers of the Upanayana ceremony in contemporary times, however this was not always the case. Generally, this ceremony should be performed before the advent of adulthood.

Upanayana
Upanayana literally means "the act of leading to or near, bringing", "introduction (into any science)" or "initiation" (as elucidated by Monier-Williams). Upanayana is formed from the root √ni meaning 'to lead'. Nayana is a noun formed from the root √ni meaning 'leading to'. The prefix upa means 'near'. With the prefix the full literal meaning becomes 'leading near (to)'. The initiation or rite of passage ceremony in which the sacred thread is given symbolizes the child drawn towards a school, towards education, by the guru or teacher. The student was being taken to the Gods and a disciplined life. As explained by PV Kane, taking (the child) near the acarya (for instruction), or alternately "introducing to studenthood". It is a ceremony in which a teacher accepts and draws a child towards knowledge and initiates the second birth that is of the young mind and spirit.

Variations
A popular variation is Maunjibandhana, derived from two words munja, a type of grass, and bandhana which means to tie or bind. The munjha grass is tied around the waist. This word was used by Manu. Another variation is vratabandha(na) meaning "binding to an observance". The word janeu is a condensed version of yagyopaveeta. The ceremony is also known as punal kalyanam (meaning auspicious thread ceremony) and Brahmopadesa.

Yajnopavita
The sacred thread or upper garment is called the yajnopavita (यज्ञोपवीतम्), used as an adjective, which is derived from the terms yajna (sacrifice) and upavita (worn). The literal meaning would then become "something worn on the body for the sacrifice". Accoutrements offered along with the yajnopavita may include be a danda (staff) and a mekhala (girdle).

Background
The earliest form of this samskara, whose name there are no records of, may have been to mark the acceptance of a person into a particular community. Indologically, the ritual is present in the Gr̥hyasūtras and Dharmasūtras and Dharmaśāstra, as well as a couple of times in the Saṃhitas.

Educational courses or training has been referred to in the Chandogya Upanishad and in the Yājñavalkya Smṛti; Gharpure (1956) writes that during the Smriti period, Upanayana may have attained a permanent fixture if the life of students to be as compared to being optional before.

In the Atharvaveda, and later in the Sutras period, the word Upanayana meant taking responsibility of a student, the beginning of an education, a student's initiation into "studentship" and the acceptance of the student by the teacher. Preceptors could include a guru, acharya, upadhyaya, and rtvik.

Gradually, new layers of meaning emerged, such as the inclusion of goddess Savitri or Saraswati, with the teacher becoming the enabler of the connection between this goddess and the student. The meaning was extended to include Vedangas and vows among other things.

The education of a student was not limited to ritual and philosophical speculations found in the Vedas and the Upanishads. It extended to many arts and crafts, which had their own, similar rites of passages. The Aitareya Brahmana, Agamas, and Puranas genres of literature in Hinduism describe these as Śilpa Śastras. They extend to all practical aspects of culture, such as the sculptor, the potter, the perfumer, the wheelwright, the painter, the weaver, the architect, the dancer, and the musician. The training of these began from childhood and included studies about dharma, culture, reading, writing, mathematics, geometry, colours, tools, as well as traditions and trade secrets. The rites of passage during apprentice education varied in the respective guilds. Susruta and Charaka developed the initiation ceremony for students of Ayurveda. The Upanayana rite of passage was also important to the teacher, as the student would therefrom begin to live in the gurukula (school).

Upanayana became an elaborate ceremony, that includes rituals involving the family, the child and the teacher. A boy receives during this ceremony a sacred thread called the yajnopavita to be worn. The yajnopavita ceremony announces that the child had entered into formal education. In the modern era, the Upanayana rite of passage is open to anyone at any age. The Upanayana follows the Vidyāraṃbhaṃ, the previous rite of passage. Vidyāraṃbhaṃ became an intermediary samskara following the evolution in writing and language. Vidyāraṃbhaṃ now marked the beginning of primary education or literacy while Upanayana went on to refer to spiritual education. The Upanayana can also take place at the student's home for those who are home-schooled. Ceremonial bhiksha as one of the rituals during Upanayana became important, attaining sizeable proportions. The actual initiation occurred during the recitation of the Gayatri Mantra. The spiritual birth would take place four days after the initial Upanayana rituals. It was then that the last ritual was performed, the Medhajanana. The Samavartanam or convocation ritual marked the end of the course. The Upanayana became a permanent feature around the Upanishadic period.

Attire includes a danda or staff and a mekhala or girdle.

Age and varna
In Hindu traditions, a human being is born at least twice—once at physical birth and second at intellectual birth through teacher's care. The first is marked through the Jatakarman rite of passage; the second is marked through Upanayanam or Vidyarambha rites of passage. A sacred thread was given by the teacher during the initiation to school ceremony and was a symbolic reminder to the student of his purpose at school as well as a social marker of the student as someone who was born a second time (dvija, twice born).

Many medieval era texts discuss Upanayana in the context of three of the four varnas (caste, class) — Brahmins, Kshatriyas and Vaishyas. The ceremony was typically performed at age eight among the Brahmins, at age 11 among the Kshatriyas, and age 12 among Vaishyas. Apastamba Gryha Sutra (verse 1.1.1.27) places a maximum age limit of 24 for the Upanayana ceremony and start of formal education. However, Gautama Gryha Sutra and other ancient texts state that there is no age restriction and anyone of any age can undertake Upanayanam when they initiate their formal studies of the Vedas.

Several texts such as Sushruta Sutrasthana, however, also include the fourth varna, the Shudras, entering schools and the formal education process, stating that the Upanayana rite of passage was open to everyone.

The large variation in age and changes to it over time was to accommodate for the diversity in society and between families.

Vedic period texts such as the Baudhāyana Grihyasutra encouraged the three Varnas of society to undergo the Upanayana.

Gender and women
In some regions, in modern times, some girls undergo Upanayana rite of passage. In ancient and medieval eras, texts such as Harita Dharmasutras, Asvalayana Grhya Sutra and Yama smriti suggest women could begin Vedic studies after Upanayana.

Girls who decided to become a student underwent the Upanayana rite of passage, at the age of 8, and thereafter were called Brahmavadini. They wore a thread or upper garment over their left shoulder. Those girls who chose not to go to a gurukula were called Sadyovadhu (literally, one who marries straight). However, the Sadyovadhu, too, underwent a step during the wedding rituals, where she would complete Upanayana, and thereafter wear her upper garment (saree) over her left shoulder. This interim symbolic Upanayana rite of passage for a girl, before her wedding, is described in multiple texts such as the Gobhila Gryha Sutra (verse 2.1.19) and some Dharmasutras.

Yajnopavita

The sacred thread or the yajnopavita has become one of the most important parts of contemporary Upanayana ceremonies. There are accordingly a number of rules related to it. The thread is composed of three cotton strands of nine strands each. The strands symbolise different things in their regions. For example, among Tamils, each strand is for each of the Tridevi, the supreme trinity of the Hindu goddesses Saraswati, Lakshmi, and Parvati. According to another tradition, each of the nine threads represents a male deity, such as Agni, Bhaga, and Chandra.

The predecessor to the sacred thread was an upper garment (such as a dupatta or an uparane). However, as traditions developed, the upper garment began to be worn continuously. The usage of a thread grew out of convenience and manageability, becoming more popular than alternatives such as a kusa rope.

The ancient Sanskrit texts offer a diverse view while describing the yajñopavītam or upavita. The term upavita was originally meant to be any upper garment, as stated in Apastamba Dharmasutra (verse 2.2.4.22–2.2.4.23) or, if the wearer does not want to wear a top, a thread would suffice. The ancient Indian scholar Haradatta states, "yajñopavītam means a particular mode of wearing the upper garment, and it is not necessary to have the yajñopavīta at all times".

There is no mention of any rule or custom, states Patrick Olivelle, that "required Brahmins to wear a sacred string at all times", in the Brahmanical literature (Vedic and ancient post-Vedic). Yajnopavita, textual evidence suggests, is a medieval and modern tradition. However, the term yajnopavita appears in ancient Hindu literature, and therein it means a way of wearing the upper garment during a ritual or rites of passage. The custom of wearing a string is a late development in Hinduism, was optional in the medieval era, and the ancient Indian texts do not mention this ritual for any class or for Upanayana.

The Gobhila Gryha Sutra (verse 1.2.1) similarly states in its discussion on Upanayana, that "the student understands the yajnopavita as a cord of threads, or a garment, or a rope of kusa grass", and it is its methods of wearing and the significance that matters. The proper manner of wearing the upper garment or thread, state the ancient texts, is from over the left shoulder and under the right arm. yajnopavita contrasts with Pracinavita method of wearing the upper garment, the latter a reverse and mirror image of former, and suggested to signify rituals for elders/ancestors (for example, funeral).

The idea of wearing the upper garment or sacred thread, and its significance, extended to women. This is reflected in the traditional wearing of sari over the left shoulder, during formal occasions and the celebration of rites of passage such as Hindu weddings. It was also the norm if a girl undertakes the Upanayana ceremony and begins her Vedic studies as a Brahmavadini.

The sacred Yajnopavita is known by many names (varying by region and community), such as Bratabandha, Janivaara,  Jaanva, Jandhyam, Poita, Pūṇūl, Janeu, Lagun, Yajnopavita, Yagyopavit, Yonya and Zunnar.

Doubts about Upanayanam in old texts
Scholars state that the details and restrictions in the Upanayana ceremony is likely to have been inserted into ancient texts in a more modern era. Hermann Oldenberg, for example, states that Upanayana — the solemn reception of the pupil by the teacher to teach him the Veda — is joined into texts of Vedic texts at places that simply do not make any contextual sense, do not match the style, and are likely to be a corruption of the ancient texts. For example, in Satapatha Brahmana, the Upanayana rite of passage text appears in the middle of a dialogue about Agnihotra; after the Upanayana verse end, sage Saukeya abruptly returns to the Agnihotra and Uddalaka. Oldenberg states that the Upanayana discussion is likely an insertion into the older text.

Kane, in his History of Dharmasastra reviews, as well as other scholars, state that there is high likelihood of interpolation, insertion and corruption in dharma sutras and dharma sastra texts on the Upanayana-related rite of passage. Patrick Olivelle notes the doubts in postmodern scholarship about the presumed reliability of Manusmriti manuscripts. He writes, "Manusmriti was the first Indian legal text introduced to the western world through the translation of Sir William Jones in 1794". This was based on the Calcutta manuscript with the commentary of Kulluka, which has been assumed to be the reliable vulgate version, and translated repeatedly from Jones in 1794 to Doniger in 1991. The reliability of the Manusmriti manuscript used since colonial times, states Olivelle, is "far from the truth. Indeed, one of the great surprises of my editorial work has been to discover how few of the over fifty manuscripts that I collated actually follow the vulgate in key readings."

Nepal
In Nepal, a ceremony is held which combines choodakarma (tonsure, shave the head) and Upanayana saṃskāra locally known as Bratabandha (Sanskrit brata = promise, bandhan = to be bound). In Nepal, The one who wears the secred thread are called as Tagadhari.

This Sanskara involves the participation of entire family and a teacher who then accepts the boy as a disciple in the Guru–shishya tradition of Hinduism. Gayatri Mantra marks as an individual's entrance to a school of Hinduism. This ceremony ends after the boy goes for his first alms round to relatives and leave for the guru's ashram. Traditionally, these boys were sent to learn in a gurukula system of education but in modern times, this act is only done symbolically.

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title: Upanayana


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Talk:J. W. Dunne

Books
Books include _An Experiment with Time_ (1st ed. 1927) and _The Serial Universe_.

experiment http://www.amazon.com/exec/obidos/tg/detail/-/0571059961/

i found serial universe in z-shops. the earliest date for it was 1938, but i don't if thats the first printing or not.

 * See the bibliography for a fuller list of his writings. -- Steelpillow (talk) 11:25, 31 January 2008 (UTC)

The Serial Universe was first published in 1934.Olamim (talk) 16:22, 30 December 2011 (UTC)

Dunne D.9 aircraft
The description of the D.9 given here may not be correct. According to Jane's of 1913 (See Jane, FT; Jane's all the world's aircraft 1913, Sampson Low (1933), reprinted David & Charles, 1969, p.47) the D.9 was a biplane design and 5 examples were under construction through 1912-1913. Can anybody provide a reference for the current description as a monoplane that crashed? -- Cheers, Steelpillow (Talk) 08:56, 2 May 2010 (UTC)
 * I found these references quoted but cannot confirm the quotations:
 * Lewis, P.; British Aircraft 1809-1914, Putnam (1962). "The D.9 was a tailless sesquiplane of somewhat complicated form designed by Dunne during 1913, with the assistance of C. R. Fairey in the stress calculations. The machine was not completed." and "The James Monoplane was built during 1913 by Levis Ltd., at Stechford, Warks., and was designed by a Mr. James in conjunction with Lt. J. W. Dunne. It was powered by the 35 h.p. five-cylinder in-line Levis two- stroke engine, which was designed by H. Newey, who was associated with the Levis Company, formed in 1909 by William and Arthur Butterfield as Butterfield Brothers. The engine was mounted inverted in the nose of the single-seat fuselage, on either side of which were the triangular-shaped wings with their leading-edges sharply swept back, resulting almost in a delta plan-form. The wing was braced from a cage-like cabane structure which acted also as a crash-pylon. The original name of Mayfly was changed to Leonie, and the machine was to have had floats fitted for testing on Edgbaston Reservoir. Instead, however, it was equipped with a land undercarriage consisting of wheels and skids, and was taken to Castle Bromwich playing-fields, where it caught one wing-tip on a goal-post during its first take-off and was wrecked."
 * Goodall, M. and Tagg, A.; British Aircraft before the Great War, Schiffer (2001). "DUNNE D.9 monoplane (Also referred to as the James monoplane). This was a tailless pusher design of almost delta wing form. It was a single-seater with a protective cage above the cockpit, serving also as an anchorage for the bracing wires. The wheels on the twin skid undercarriage were covered by fairings. The power plant was a 35hp Levis five-cylinder inline two-stroke engine designed by H. Newey, mounted inverted in the nose, and driving the propeller by extension shaft. Dunne was assisted by C.R. Fairey with the stressing and the machine was constructed in 1913 for a Mr. James by Levis Ltd. of Stechford, Warwickshire, motorcycle manufacturers. The name 'Leonie' and the initials 'AB', probably of Arthur Butterfield, one of the directors of Levis, were painted on the wheel covers. The machine was wrecked on its first attempt at flight by hitting an obstruction on a playing field at Castle Bromwich, forestalling the proposal to fit floats for later trials on Edgbaston Reservoir."
 * The accounts of a single machine which was completed and a production batch which may not have been completed are not consistent. Jane's account of the production batch is at least both contemporary and authoritative. It gives the engine as a 80 hp Gnome, a rotary type. A photo here shows a monoplane with a different kind of engine and "Leonie" on the wheel spats, which I can only assume is the one-off "James monoplane". I'll edit the article accordingly. — Cheers, Steelpillow (Talk) 14:34, 18 November 2013 (UTC)
 * Unpublished documents in the Science Museum records and archive show Lewis to be substantially correct on the D.9. Jane appears to have mistaken the total work in hand to relate to the D.9. Lewis is also fairly close on the other aircraft, whose engine is on display there, but made a couple of slips. It is more accurately referred to as the "Levis-Belmont" monoplane, the engine was not inverted, and there is no evidence whatsoever that Dunne was involved beyond the fact of his patents on some of the technology. Goodall & Tagg appear to have been misled by subsequent confused researchers and to have further embellished their muddle in a botched attempt to resolve it. I'll have to check whether unpublished archives, accessible only by individual permission, are acceptable as WP:RS. — Cheers, Steelpillow (Talk) 09:51, 16 August 2018 (UTC)

Complete revision required
As I just stumbled upon this article again and tried to fix a few small areas, I realized that tiny "patches" would not suffice. This article requires an entire rewrite. Comments? FWiW Bzuk (talk) 12:11, 2 May 2010 (UTC).
 * I don't know about biographies, I'm just trying to improve the material on his aircraft. At the moment there are three half-baked articles, each covering a more or less arbitrary selection of types and scraps of theory amid much repeated content, and with several types not covered at all. IMHO it would be better to merge them all into a single article on say Dunne aircraft, and move the list over to there. Good idea? -- Cheers, Steelpillow (Talk) 13:27, 2 May 2010 (UTC)
 * Probably makes sense but in dealing with a biographical article on the individual behind these inventions and scientific theories, a lot more attention has to be paid to the person's life. FWiW Bzuk (talk) 13:40, 2 May 2010 (UTC).
 * A lot of the information in the article is at variance with sources and will need to be scruptiously checked. FWiW Bzuk (talk) 13:43, 3 May 2010 (UTC).
 * Tell me about it :( . I'm still arguing over the the list of aircraft. -- Cheers, Steelpillow (Talk) 13:57, 3 May 2010 (UTC)
 * The more I find in his books and elsewhere, the more suspect becomes the fine detail of the biographical dates and the like. I think the best option is some heavy pruning and maybe a bunch of fact tags to boot. But I do wonder what was the original source for much of the article, biographical material on him is hard to find. — Cheers, Steelpillow (Talk) 13:32, 8 February 2014 (UTC)

List of aircraft

 * The use of authoritative sources may be the only recourse and I would suggest: British Aircraft 1809–1914 by Peter Lewis (1962) who has a comprehensive account of Dunne aircraft from D.1 to D.10, set up as individual chapters and The Aeroplanes of the Royal Flying Corps (Military Wing) by J.M. Bruce (1982) who concentrates on the D.8 in a separate chapter. FWiW Bzuk (talk) 19:04, 3 May 2010 (UTC).

 * Steelpillow will know this, but on the aircraft and Dunne's work at and before Farnborough, and later with the Blair Atholl Syndicate, I'd recommend Goodall and Tagg "British Aircraft before the Great War" (2001). Their bibliography includes both Bruce and Lewis.  Be interesting to compare Lewis (I've not got this) and G&T.  My view is that this article, like most of its kind, should be brief on the aircraft .  These are better dealt with in their own articles, though of course we have to be consistent with details that appear in both. Cheers,TSRL (talk) 19:32, 3 May 2010 (UTC)
 * How extensive is the Goodall and Tagg resource? Certainly Lewis and Bruce are much more well known as aviation historians. FWiW, a new authoritative source is always useful. Bzuk (talk) 17:40, 4 May 2010 (UTC).

They aim to cover everything British, however obscure, failures and flyers, before WWI. As an example, they have 6 large format pages on the Dunne aircraft. There's an article on each and an introductory piece on Dunne's aeronautical career. The D.8, for example, has about 390 word plus specs plus 4 pics. When I launched the D.8 article, I found both G&T and Bruce important sources. They have different emphases. Bruce, for example has an interesting long quote from the RFC testing day, in a piece more than twice as long as G&T. There is a bit more on the differences with the D.5, the French connection and the later development of the D.8 in G&T; Bruce, naturally emphasises the RFC experience. As I said in arguing over the the list of aircraft, both books struggle at places where, I suspect, the historical record is a bit thin.

As far as Dunne goes, there is only overlap between G&T and Bruce on the D.8; the books are mostly complementary, as one's period starts where the other ends. Both G and T separately have produced focussed aviation books; I don't know how well regarded they are, but Tagg's book on the Green and ENV engines probably has little competition (and fewer sales?). Seems to me to be a good attempt to get comprehensive cover of a period where records are incomplete, though sometimes the joins show. It's probably been professionally reviewed somewhere.

There is a copy of Peter Lewis's book coming my way shortly, and that will make interesting comparative reading. I'll perhaps report back. Cheers, TSRL (talk) 19:43, 4 May 2010 (UTC)
 * Sounds like an excellent resource and will be of use in adding to the story of Dunne aircraft. FWiW, I can provide the details on the Burgess-Dunne aircraft that was officially Canada's first military aircraft. It did have a very short lifespan and an unfortunate demise, however. Bzuk (talk) 20:35, 4 May 2010 (UTC)

 * According to Fahey's 1946 "US Army aircraft", p.8, one Burgess-Dunne was also procured by the US signal corps. Engine and fuselage apart, the B-Ds look like D.8s, though sometimes on floats.  There is a Flight article about the "hydro-biplane", with a g/a diagram, in the 19 June 1914 issue, p.644-7. I don't know how many were produced; two or more, evidently.
 * Nieuport production is another unknown (to me at least). We know there was a version of the D.8 in the 1913 Paris show (see Dunne D.8), which had significant alterations both structural and aerodynamic, but did it fly and were any more built before the outbreak of war? There is a curious Flight snippet (12 April 1913 p.419) about the successful flight testing of the French-built Dunne monoplane. Eh?TSRL (talk) 07:51, 5 May 2010 (UTC)

 * Having now seen Dunne's m/s (see next section), think that it was a monoplane, the D.7 bis, which JWD says he flew at Villacoublay in 1913. The Flight article says the pilot was Percival, but maybe both men flew it.  The "French-built" comment is now a puzzle.--TSRL (talk) 09:26, 13 May 2010 (UTC)

 * Just as an aside in 1953 Katherine Atholl wrote a letter to the (London) Times, she was the wife of the chairman of the company formed to finance the "Dunne". She says two "Dunnes" known in the United States as "Burgess Dunnes" were used for training purposes in the American Navy during the first world war. MilborneOne (talk) 11:48, 5 May 2010 (UTC)

 * That's useful: so at least three US and one Canadian. Does anyone have Fahey's "Ships and aircraft of the US Fleet" as an alternative ref? Bzuk, did Canada have more than one, do you know?TSRL (talk) 19:27, 5 May 2010 (UTC)

 * Just one example, the Burgess-Dunne #2, was bought by the Canadian Army as Canada's first military aircraft. First flown to Quebec City by Clifford Webster, it was to be deployed to France during the First World War, but was lashed to the deck of a ship. When the ship encountered rough seas during the Atlantic crossing, the Burgess-Dunne was so severely damaged that the aircraft was scrapped soon after. FWiW Bzuk (talk) 22:10, 5 May 2010 (UTC).

 * Having looked on AbeBooks I've realised that Fahet's Naval book is not the equivalent of the ASAA one, which included 1908-1946. So not helpful.TSRL (talk) 19:37, 5 May 2010 (UTC)
 * There are two tiny entries in aerofiles for types AH-7 and Ah-10 (Naval). Is E.T. Woodridge reliable?  If so then [] is useful, particularly on the Burgess-Dunne.TSRL (talk) 20:12, 5 May 2010 (UTC)

Goodall & Tagg's assertion that the Dunne-Huntington did not have a D number, and that the D.2 was an unbuilt, smaller glider version of it is confirmed by a letter to Flight [] from GWB Lacey, Asst Keeper at the London Science Museum, which has a list of the Dunne aircraft up to the D.4, signed by Dunne himself. I'll alter the list.TSRL (talk) 21:12, 5 May 2010 (UTC)
 * Lacey quotes "an extract" from Dunne's statement: it would be interesting to see if the rest of it clarified some of the uncertainties debated below. Anyone have a Science Museum contact?TSRL (talk) 21:37, 5 May 2010 (UTC)

 * On the last point: I've now got a copy of Dunne's notes. See section D.6 and Dunne's names, below and also talk:Dunne D.6.

Dunne aircraft
Moved from User talk:TSRL -- Cheers, Steelpillow (Talk) 21:09, 5 May 2010 (UTC)

I am having trouble referencing a couple of your [TSRL's] edits to the article on J. W. Dunne.

 * You added the Dunne-Capper monoplane. I can find no reference to this type. Indeed, Flight (1943) records that Capper asked for a biplane, which emerged as the D.1.

 * You also added Dunne D.9 (1913 monoplane; crashed first flight). Jane's (1913) records the D.9 as a biplane type, of which several examples were being constructed at the time.

Can you provide references for your remarks, or is it OK if I edit the article according to my knowledge? -- Cheers, Steelpillow (Talk) 11:55, 2 May 2010 (UTC)

 * My source is the 2001 "British Aircraft before the Great War" by Goodall & Tagg (ref in D.8 article). The Dunne-Capper, appearing as a glider in 1907 at Blair Atholl, was finally found a suitable engine and flown thus in Jan 1911.  It was developed (same wing, new airframe) into the D.6, which first flew in June 1911.  There's an article on the latter in Flight 19110624 (I'm thinking of doing an article on these three).  The 1913 D.9, definitely a monoplane in the photo, was also known as the James monoplane, and was a near delta with a nose engine but rear prop, driven by a long extension shaft.  Fairly obscure as it crashed on its first flight in Castle Bromwich.

 * There might be a problem of nomenclature, as often with aircraft of this period when folk were busy getting stuff in the air and less concerned with numbering. Does the JAWA D.9 look like the D.8? Compare Flight 19131115 p.1241-5, esp g/a on p.1243.  I'll try D.9 in Flight, but most of their Dunne articles do not mention D numbers.  Cheers,TSRL (talk) 16:11, 2 May 2010 (UTC)

 * Found nothing under James monoplane, etc. I've added that source and removed the cn from John William Dunne.  By the way, Goodall says the D.2 was a projected smaller version of the Dunne-Huntington triplane, not built.  He also notes that the Dunne-Huntington triplane, which was built, has been described as a triplane, biplane or monoplane, and looking at the pics I can see why!TSRL (talk) 16:56, 2 May 2010 (UTC)

 * Goodall also notes that Capper was associated with the D.1 glider. Col Capper engaged Dunne at the Balloon Factory and asked him to develop his ideas, starting with a glider.  Capper also flew it on all(?) of its flights.  JWD was still at Farnborough when the Dunne-Capper monoplane flew, but was with the Blair Atholl Syndicate by the time it flew under power.TSRL (talk) 17:06, 2 May 2010 (UTC)

I do not have easy access to Goodall & Tagg. According to Poulsen (Flight 1943-1376), "... as early as 1905 Dunne had designed his tailless monoplane wing. In the following year he showed it to Col. Capper, of the Army Balloon Section (from which later grew the R.F.C., R.N.A.S., and R.A.F.). Col. Capper, however, asked for a biplane, and a biplane version was designed and built at Blair Atholl." This biplane is presumably the D.1, and yes, Capper went along for the ride. But the implication is that he was not involved in the design of the preceding monoplane, which would later emerge as the basis for the D.6. So - do we believe Dunne's fellow Brit writing in 1943 or an American writing in 2001? -- Cheers, Steelpillow (Talk) 17:30, 2 May 2010 (UTC)

Also, Poulsen records that Dunne had already designed the monoplane by 1905, while Jane's (1913) records that Dunne had patented it by 1906, when he was first engaged by the British Army - presumably via Capper, who according to Poulsen was asking for a biplane instead. If Capper was involved in the design of the pre-Army monoplane, then how could Dunne patent it in his own name? All this leads me to mistrust Goodall & Tagg's account - I wish I could read it for myself. -- Cheers, Steelpillow (Talk) 17:42, 2 May 2010 (UTC)

Sorry to keep adding thoughts, but do Goodall & Tagg give any exact account of why they call it the Dunne-Capper? -- Cheers, Steelpillow (Talk) 17:55, 2 May 2010 (UTC)

 * This is what G&T have to say, under the heading "Dunne-Capper monoplane glider" - As early as 1905 Dunne had made a model of a monoplane, the design of which was submitted to the War Office and rejected. A full size glider version of this was made at Farnborough in 1907 under Col. Capper's authority. It is believed to have been tested at Blair Atholl, unsuccessfully by Capper, at the end of August during the first official expedition. [they then go on to describe the aircraft.]

 * I'm not troubled by nationality, but certainly "Bert" Tagg was British, working with Hawkers from 1935 to retirement. Goodall was in the RAF (national service?) and worked in the UK before his retirement to a post at Brooklands Museum, though I don't know where he was born. Theirs is certainly the fullest account I've seen of Dunne's machines, though sometimes the story creaks a bit, probably where they are trying to understand fragmentary surviving records. Bruce's account of the D.8 also stumbles a little. It's a pity Flight's 1911 article on the D.6 does not mention precursors.  G&T have a photo of the powered Dunne-Capper.

 * On the Patent: probably should look to see what he patented. I don't think one can patent an aeroplane, but you can patent a method of control or a way of producing stability.  Given that, Dunne could have his patent and Capper his name on the plane.  Though having said that, I'd guess that both of them were more concerned about getting the thing flying than exactly what to call it.

 * So I think JWD made a model before he went to Farnborough in 1906, was there advised by Capper to build a biplane. Apart from the D-Huntington triplane and the D-Capper monoplane glider, that's what he did at Farnborough. Don't think the fact (if it is) that C said biplanes at the start rules out his (C's) involvement with a monoplane later; this monoplane was based on the 1905 model.  JWD was allowed to take his planes when he left, including the Dunne-Capper, and only in late 1910 found an engine for it.  This then developed into the D.6.  I'm rushing a bit - got to go - but I think that is consistent with both G&T's details and Poulsen, who has less historical detail.  Cheers,TSRL (talk) 20:28, 2 May 2010 (UTC)

 * Trivia: I've just learned that Goodall is British. He is a descendent of Charles Goodall, whose company based in Camden were the dominant UK manufacturers of playing cards in the 19th century.TSRL (talk) 10:50, 3 May 2010 (UTC)

I find several inconsistencies in your interpretation, based in part on lack of clarity from G&T.

We have two parallel accounts in which a glider is made under Capper's instruction, and flown by Capper at Blair Atholl in 1907. G&T say, "A full size glider version of this ...", implying but not stating a monoplane, and qualify the whole story with "it is believed...". Flight and Jane's both state unambiguously that it was the D.1 biplane, subsequently given a motor and damaged before takeoff that same year. What do G&T mean by "it is believed"? By whom? On what evidence? Are they saying that two gliders were flown by Capper that year at Blair Atholl, possibly on different occasions? Questions, questions, and doubts about what G&T really mean or what evidence they really have.

 * Its quite clear with book open that G&T are talking about a monoplane, as their header says. They also, in another section, talk about the biplane D.1 and its testing at BA in summer 1907.  "It is believed" refers to the testing of the monoplane at about the same time.

Since the Farnborough operation was funded by the Army, I cannot see Capper sanctioning a monoplane and then participating in its design at Army expense, having expressly asked for a biplane instead. The idea is just not tenable.

 * Possibly, but so far what evidence we have (G&T) says it was so: one would need another source to support a POV.

All this so far suggests that the "D-C monoplane" was the "model" glider that Dunne first showed to Capper. From what you say, G&T make no mention of any role which merits the "Capper" part of "Dunne-Capper". On this evidence, the name appears to have been coined by G&T and has no basis in historical record.

 * I've been wondering when any of the names cames into use, for Flight just talks about "The Dunne Biplane" etc. Even Paulsden, much later, does not use the D numbers.  As I understood it from J. W. Dunne, Capper was the engineer involved.  What name it had in 1907 is not known to me; what does Lewis have to say? Whatever it was called, there was an aircraft.

However: Does G&T's photo of the "powered D-C" look significantly different from the D.6? When was it said to have flown, and was it successful? It occurs to me that the D.6 might be a more or less new design, and that the original monoplane might have been given a motor as an attempt by Capper at a "quick win" while the D.1 was being built. This scenario seems compatible with both stories, but again lacks real evidence. -- Cheers, Steelpillow (Talk) 13:53, 3 May 2010 (UTC)

 * The two photos of the powered D-C (PDC) and the D.6 don't show the wing planform, but with that proviso they look the same except that the elevons are clearly visible on the D.6 but not on the PDC. Since the PDC was a direct adaptation of the glider and the latter was controlled by weight shifting, that would make sense. G&T's accounts have the first, unsuccessful, attempts at flight of the PDC on 5/14 Jan 1911 (4 years on) on Salisbury Plain.  There were, they say some modifications made, but the double A frame fuselage structure of the glider was retained.  The June 1911 Flight (and G&T) article shows that the D.6 had a largely rectangular structure.  By this time, of course, JWD had been gone from Farnborough for more than a year, and nothing more is heard of Capper in his story. Cheers,TSRL (talk) 20:24, 3 May 2010 (UTC)
 * Dunne updated several models by fitting a new fuselage structure to an old wing. The change from A frame to rectangular tells us nothing about the origins of the D6 wing. If the PDC and D.6 are indeed different, then we are asked to swallow a remarkable coincidence - two gliders flown by Capper at Blair Atholl in 1907, and two powered monoplanes flown in 1911, and no mention of either DC/PDC anywhere except some qualified remarks by G&T. Time to move this discussion to Talk:John William Dunne and ask if Bruce or Lewis sheds any light? -- Cheers, Steelpillow (Talk) 19:39, 4 May 2010 (UTC)

 * Happy to make that move. I'm not sure we know enough about the dates to talk about coincidences. PDC ff in Jan 1911 as I read it, but D.6 only before June (dated by Flight article). It seems the PDC was modified, or a variant produced, several times in 1911, leading the D.6 and D.7 but with early aircraft modifications could often be done quickly (and not be well recorded).  For sure, we have the photos of related but distinct powered aircraft (two of the PDC, in different stages of modification and one of the D.6 in G&T plus several more D.6 in Flight). I've just noticed that whilst the first PDC photo in G&T does not show elevons, as I said before (though it might be the angle of the shot), the second pic shows them clearly along with an altered u/c. Re Capper, remember the placard on the D.7 at the Aero Show. Bruce's book is on the RFC (unless there is another one I don't know about), so only contains the D.8 and does not help with the monoplane.  However, I hope to be the proud owner of a copy of the Lewis book quite soon (few days). It will be interesting to see the similarities and differences: compare and contrast, as I used to ask of my students! I'll report back anything useful.  Cheers, TSRL (talk) 20:13, 4 May 2010 (UTC)

 * Further evidence, from Flight 1910, "The Blair Atholl Experiments" (1910-0711,-0721) shows four photographs claimed to be of the original experiment. They all show a biplane, before Capper flew it into a wall. Subsequent to these experiments another, powered, machine was commenced in 1907 and piloted in 1908 by Lt. L.D. Gibbs, and there is also a photo of this, clearly labelled D4 on the fin/endplate. No hint of any monoplane. Interestingly, the glider that Gibbs few earlier in 1908 is described here as a small-scale replica of this machine (i.e. D1/4) and by Jane (1013) as the D.3. -- Cheers, Steelpillow (Talk) 17:03, 3 May 2010 (UTC), updated -- Cheers, Steelpillow (Talk) 17:47, 3 May 2010 (UTC)

 * Interesting, partly because it emphasises the secrecy about these tests, which is why they were at BA and why some details are hard to track down. G&T use Fig 2, labelled D.1A (D.1B was the powered version) and Fig 5, the D.4. I should have spotted that before wondering when the D numbers came in! No monoplane, as you say, but "absence of evidence is not evidence of absence".  Maybe this article provoked G&Ts "believed to have been tested" caution.
 * I was wrong to say that Capper went out of the picture. When the D.7, a slightly smaller version of the D.6 appeared, incomplete at the 1911 Aero Show at Olympia, it had a caption saying "Built to the order of Col. J. E. Capper".  So Capper did keep in touch with developments and call for them, to the DC glider lineage. I'll look later to see if G&T have anything to say re your last sentence. Cheers,TSRL (talk) 20:54, 3 May 2010 (UTC)

 * G&T have the D.3 as a hang glider, fitted with elevons and some rapidly discarded leading edge control features. It was built "to test features of the D.4" and flown by Gibbs.  A light machine, it had only 40% of the wing area of the D.4. So they agree with Jane on notation.

 * I'll close this evening with a speculation: in those days it was easier to design a strong biplane aircraft than a monoplane, and you got a lighter wing loading (overall good at this point). So an aerodynamicist like JWD is likely to have greater need of an engineer like JEC for a monoplane rather than for a biplane.  It's a POV! TSRL (talk) 21:23, 3 May 2010 (UTC)
 * The sources I have consider Capper a mentor to the younger Dunne and his name added to the Dunne aircraft was a tribute and acknowledgment of the assistance that Capper had extended to Dunne. FWiWBzuk (talk) 22:10, 5 May 2010 (UTC).

Update on the monoplane. This memoir from Gurr, whom Capper appointed as Dunne's assistant for the whole project: "As a result, J. W. Dunne decided to build a man-lifting glider (monoplane) and a full-scale tailless biplane in the factory workshops. The machines were made in sections and final assembly took place in the balloon shed behind locked doors. In July, 1907, J. W. Dunne, Lt. Westland, R.E., six selected tradesmen of the Balloon and Kite Section and two civilian assistants entrained at Farnborough Station for Blair Atholl ... Work on assembly of the man-lifting glider commenced and was completed by the end of August. Capt. Gibbs ... arrived a few days later. A number of short glides were made by Gibbs, but the machine was eventually wrecked." Odd that in his list of early types for the Science Museum, Dunne makes no mention of it. — Cheers, Steelpillow (Talk) 19:27, 3 March 2014 (UTC)

D.6 and Dunne's descriptions
I've now got, courtesy of the London Science Museum, a full copy of Dunne's description of some of his aircraft, part of which appeared in the letter referred to above. I've also started a new page, Dunne D.6 (though it covers all the monoplanes and possibly "The Dunne Monoplanes" would be a better name?), and I've put the relevant parts of Dunne's doc on its discussion page, together with an explanation of the purpose of the doc and comparisons of the interpretation of two standard texts.TSRL (talk) 07:45, 13 May 2010 (UTC)
 * I hesitated to mention this, but the formatting of the citations and references are improperly done, but if I get involved, I see a ton of work ahead so I just mention it if you wish to have it corrected. The problem seems to be in using another @#$%^& template that does not format the readout correctly. FWiW Bzuk (talk) 13:52, 13 May 2010 (UTC).

 * Thanks Bzuk. Can you be a bit more explicit, because (apart from the Flight refs) everything is in the style I've used for ages without comment?  It looks fine from here.  Oh, and the two column list.  I can't read your message between another and template; what template?  Cheers,--TSRL (talk) 14:28, 13 May 2010 (UTC)

 * A lot of general remarks about the tailless swept design are included and/or repeated in articles on specific types. I think we need a Dunne aircraft article to pull all this together so the specific articles can be streamlined. Once that is done, we may find that some can be merged. -- Cheers, Steelpillow (Talk) 15:02, 13 May 2010 (UTC)
 * TSRL, bibliography lists are arranged alphabetically by first entry, second authors are written out first name last name, third authors are et al. All of the Wiki citation templates are written as APA style and use an ISO format which does not match the body of the article's date convention. Look at Dunne D.1 for a revision that brings the material back to a standardized bibliographical style. FWiW Bzuk (talk) 15:21, 13 May 2010 (UTC)

 * Hi Bzuk, agree about alphabetical order, as done in Dunne D.6. Is the business about the difference in presentation between first names of first and later authors (with respect, a small point) laid out in the Wiki styleguides somewhere? It's certainly not used in the bibliography of books like Goodall & Tagg (2001, US pub, happens to be on my desk, for obvious reasons!). For now, I'm content to live with the product of Wiki's recommended templates, which do a good job of standardising the layout and link inlines to refs. So please don't feel the need to go in hand editing; as you know, the normal rule is not to change the cite style from that first used.

 * Maybe the way forward would be to get Wiki template editors to change the outputs to the preferred format? It can't be hard to tweak the code, and all the data is already there.  This would automatically change things without us having to change the input. Happy with that.  Cheers,--TSRL (talk) 17:18, 13 May 2010 (UTC)
 * I know that the wiki style was there but with so many errors, I was tempted to rewrite them just to have them appear properly. However, as I indicated I do not want to get into a new project at present and will leave well enough alone. BTW, as a reference librarian with a 35+ years in the field, these errors just pop up at me. Regardless, unless a rewrite is in order, I will cast a blind eye to the issue. FWiW Bzuk (talk) 18:27, 13 May 2010 (UTC).

D2 vs Dunne-Huntingdon
Jane 1913 refers to the Huntingdon example itself as the "Huntingdon (Dunne II)" and dates the original design as 1905-06. Was there really a proposed model D2 as this article presently states, or should we merge the D2 with the Dunne-Huntingdon? -- Cheers, Steelpillow (Talk) 15:02, 13 May 2010 (UTC)

 * Dunne himself says "D.2 was the designation of a proposed small glider form of the Dunne-Huntington triplane. This glider was never constructed."  So the comment on this page is correct.  Practice seems to vary with lists of manufacturer's aircraft; sometimes people include unbuilt projects, sometimes built but not flown, sometimes nothing but fliers.  I've (FWiW) tended to the middle way: a big manufacturer will have started a very large number of projects and I can't see the point of listing them, but if they got a least part built than folk may hear of them and want to know more.  I'd label these unflown. I thing the only reason for listing the D.2 separately here is that someone will ask "but it goes D.1, D.3, what about D.2."  Could equally well put it with the Dunne-Huntington list entry, though some of these are getting a bit long for a simple list. Certainly, if someone gets to write a Dunne-Huntington page they are likely to mantion the D.2.
 * I created the Dunne-Huntington triplane page, where all is now explained. — Cheers, Steelpillow (Talk) 07:05, 21 January 2018 (UTC)

 * By the way, the list mentions the D.9 and gives descriptions of two different aircraft, one from G&T and another from Jane's; Peter lewis adds a third, as an uncompleted tailless sesquiplane! Dunne does not mention it, presumably because even he did not think the Science Museum would want to model it (whatever it was).--TSRL (talk) 15:30, 13 May 2010 (UTC)
 * Lewis is correct. The D.9 was an unequal-span biplane or sesquiplane whose design was never finished. Dunne described it drily as "unsuccessful". G&T's treatment is a complete fairy-tale, embroidering imaginatively on an earlier mistake which muddled it up with somebody else's machine. — Cheers, Steelpillow (Talk) 07:26, 21 January 2018 (UTC)

The Zanonia link
This 1913 paper in Flight links the Zanonia form with several designers. And this one links Etrich (with a 1904 design) to it. There seem to be a few other mentions of Dunne and Zanonia in the Flight archive, in the same breath as it were, but only saying that Dunne's designs fall into the Zanonia type, and not that his work was inspired by the seed. GraemeLeggett (talk) 15:36, 8 February 2014 (UTC)
 * Geoffrey de Havilland's autobiography Sky Fever, Chapter 5 is explicit: "... a machine based on the vee shape of a Zanonia seed, which he [Dunne] had observed was a good glider." De Havilland replaced Cody and Dunne as the Farnborough Balloon Factory's aircraft designer, about 20 moths after they were kicked out. — Cheers, Steelpillow (Talk) 19:05, 3 March 2014 (UTC)
 * [Update] de Havilland was wrong, or at best highly misleading. Dunne explained fully why he rejected the Zanonia form in his 1913 lecture to the Aeronautical Society. Comments made in this lecture and elsewhere, and also made by his brother Frank to the writer Constance Babington Smith, make it clear that he was in fact inspired by watching seagulls. — Cheers, Steelpillow (Talk) 07:00, 21 January 2018 (UTC)

Nationality
Dunne was born in what is now Eire (Southern Ireland) but in those days was part of the United Kingdom. He was born a British subject and remained so after partition. As a young child he went to South Africa and later came to England but, AFAIK, never returned to Eire. What nationality should we give him in the article? — Cheers, Steelpillow (Talk) 18:27, 15 August 2014 (UTC)
 * OK, nobody is both watching and caring. I'll change it to what I think - that he was born a British subject and remained a British subject throughout his life. — Cheers, Steelpillow (Talk) 09:40, 11 September 2014 (UTC)
 * Just to clarify: At this time the whole of Ireland was subject to British rule. His father John Hart Dunne came from an Irish family (with Scottish blood too), made his career in the British Army and married an English woman, Julia Elizabeth Chapman. His oldest sibling, sister Marion, was born in Scotland near a British Army camp there. J.W. was born in Ireland, also near or even in a British Army camp. His two subsequent brothers were born in England, Leonard in Warwickshire and Frank in London. In other words, they were following their father's postings around and the fact that John Hart's second child was born in his own country of origin appears to be pure coincidence. Technically J.W. is roughly half-Irish and half-English. He may be found remarking wryly on this state of affairs in one of his children's books, "An Experiment with St. George" if I remember correctly. But his official nationality was British, and that's what counts here. — Cheers, Steelpillow (Talk) 10:00, 20 September 2015 (UTC)

June 2022
This has erupted again. We have to stick to WP:RS. I'd suggest that editors wishing to emphasise Dunne's Irishness or to cut cited content might find it useful to read the above, then seek reliable sources for their PoV and discuss their proposed edits here first. It is a recurrent meme in informal sources but has no basis in reliable documentation. Meanwhile I have tried to tone down the previous over-emphasis on Englishness and clarify his father's status (see also the next discussion below). — Cheers, Steelpillow (Talk) 12:20, 6 June 2022 (UTC)

Nationality of father
General Sir John Hart Dunne was born a native Irishman, in Ireland, which at that time it made him a British subject with a British passport. He rose to the rank of General in the Royal Scots Fusiliers (Duke of Edinburgh's Own), a regiment of the British Army. As such, when we qualify the nationaloty of the man "John Hart Dunne" we might qualify him as British or Irish depending on context. We may say that he was an Irishman, known as General Sir John Hart Dunne, or that he was British General Sir John hart Dunne. But what is totally wrong is to write that the titled individual was "Irish General" Sir John Hart Dunne. — Cheers, Steelpillow (Talk) 18:43, 10 July 2020 (UTC)
 * Pretty sure the Irish didnt have a seperate Army in 1875. Perhaps an Irish-born British General Sir .. may be better. Although I dont see why the origin Dunne's parents are really relevant or the unreferenced bit about ancestry. MilborneOne (talk) 18:48, 10 July 2020 (UTC)
 * the subtopic below helps explain why I opened the above discussion; another user is insisting on making a factually incorrect edit. — Cheers, Steelpillow (Talk) 08:21, 11 July 2020 (UTC)
 * They also ignored WP:BRD, which I had just asked them to respect in this edit comment and instead reverted my edit. The article history shows that this has been going on for a couple of weeks. — Cheers, Steelpillow (Talk) 08:35, 11 July 2020 (UTC)
 * Sorry to ping again, but what bits about his ancestry are unreferenced? The first sentence cites a national census, the whole para cites a book half of which is dedicated to him. — Cheers, Steelpillow (Talk) 17:56, 11 July 2020 (UTC)

Irish vs Irishman

 * ''The following reply was posted to my user talk page by . I have moved it here, where it belongs. — Cheers, Steelpillow (Talk) 08:21, 11 July 2020 (UTC)

Hi, sorry to bother you, but the Talk page on Dunne you suggested doesn’t have a discussion topic on grammatical construction.

Please think for a second. Irish is the adjective. Irishman is the (old fashioned but still acceptable) noun.

Is English your first language? If not, I explain that adjectives “describe” nouns. Dunne was a general. He was born in Ireland. Therefore he was an “Irish general”. Or, in theory, “the general was an Irishman” or “the Irishman was a general”.

Please understand, the issue here is solely the minor grammatical error. The ethnic or national background of the man is not the issue. Glen Gormley (talk) 22:37, 10 July 2020 (UTC)
 * No. The phrase "Irish general" implies a general in the Irish army. As I point out above, he was not. Your logic-chopping is misplaced. (Also, your grasp of the nuances of English grammar and of Wikipedia etiquette are wanting in other ways, but we can get to those later; one thing at a time.) — Cheers, Steelpillow (Talk) 08:21, 11 July 2020 (UTC)
 * Were the subject born a few years earlier or later, this would be less ambiguous, but I have to agree that it doesn’t work here as “Irish general”. Qwirkle (talk) 20:17, 13 July 2020 (UTC)

I think he should be considered Anglo-Irish, much like the Duke of Wellington, who was also born in Ireland but didn't considered himself Irish at all. Meanderingbartender (talk) 20:32, 13 July 2020 (UTC)
 * The Anglo-Irish were an identifiable class primarily of English descent; they were more like ex-patriots than natives. We have no reliable source for the origins of the Dunne family, so it would be premature to use that description here. — Cheers, Steelpillow (Talk) 08:39, 14 July 2020 (UTC)
 * As others have commentated, whatever he was, he wasn't an "Irish general". I am also inclined to agree with Steelpillow's comments above. Gog the Mild (talk) 21:28, 13 July 2020 (UTC)
 * Well, really he was, in certain senses; in another context this description would be workable. Here, it creates needless ambiguity. Qwirkle (talk) 17:19, 14 July 2020 (UTC)

For possible COI issues...
... related to an editor of this article: See this talk page. Valerius Tygart (talk) 14:23, 30 March 2024 (UTC)

See also User talk:Steelpillow — Cheers, Steelpillow (Talk) 15:20, 30 March 2024 (UTC)

title: Talk:J. W. Dunne


text:
Long-term potentiation

In neuroscience, long-term potentiation (LTP) is a persistent strengthening of synapses based on recent patterns of activity. These are patterns of synaptic activity that produce a long-lasting increase in signal transmission between two neurons. The opposite of LTP is long-term depression, which produces a long-lasting decrease in synaptic strength.

It is one of several phenomena underlying synaptic plasticity, the ability of chemical synapses to change their strength. As memories are thought to be encoded by modification of synaptic strength, LTP is widely considered one of the major cellular mechanisms that underlies learning and memory.

LTP was discovered in the rabbit hippocampus by Terje Lømo in 1966 and has remained a popular subject of research since. Many modern LTP studies seek to better understand its basic biology, while others aim to draw a causal link between LTP and behavioral learning. Still, others try to develop methods, pharmacologic or otherwise, of enhancing LTP to improve learning and memory. LTP is also a subject of clinical research, for example, in the areas of Alzheimer's disease and addiction medicine.

Early theories of learning

At the end of the 19th century, scientists generally recognized that the number of neurons in the adult brain (roughly 100 billion ) did not increase significantly with age, giving neurobiologists good reason to believe that memories were generally not the result of new neuron production. With this realization came the need to explain how memories could form in the absence of new neurons.

The Spanish neuroanatomist Santiago Ramón y Cajal was among the first to suggest a mechanism of learning that did not require the formation of new neurons. In his 1894 Croonian Lecture, he proposed that memories might instead be formed by strengthening the connections between existing neurons to improve the effectiveness of their communication. Hebbian theory, introduced by Donald Hebb in 1949, echoed Ramón y Cajal's ideas, further proposing that cells may grow new connections or undergo metabolic and synaptic changes that enhance their ability to communicate and create a neural network of experiences:

"Let us assume that the persistence or repetition of a reverberatory activity (or "trace") tends to induce lasting cellular changes that add to its stability.... When an axon of cell A is near enough to excite a cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A's efficiency, as one of the cells firing B, is increased."

Eric Kandel (1964) and associates were some of the first researchers to discover long-term potentiation during their work with sea slug Aplysia. They attempted to apply behavioral conditioning to different cells in the slug’s neural network. Their results showed synaptic strength changes and researchers suggested that this may be due to a basic form of learning occurring within the slug.

Though these theories of memory formation are now well established, they were farsighted for their time: late 19th and early 20th century neuroscientists and psychologists were not equipped with the neurophysiological techniques necessary for elucidating the biological underpinnings of learning in animals. These skills would not come until the later half of the 20th century, at about the same time as the discovery of long-term potentiation.

Discovery

LTP was first observed by Terje Lømo in 1966 in the Oslo, Norway, laboratory of Per Andersen. There, Lømo conducted a series of neurophysiological experiments on anesthetized rabbits to explore the role of the hippocampus in short-term memory.

Lømo's experiments focused on connections, or synapses, from the perforant pathway to the dentate gyrus. These experiments were carried out by stimulating presynaptic fibers of the perforant pathway and recording responses from a collection of postsynaptic cells of the dentate gyrus. As expected, a single pulse of electrical stimulation to fibers of the perforant pathway caused excitatory postsynaptic potentials (EPSPs) in cells of the dentate gyrus. What Lømo unexpectedly observed was that the postsynaptic cells' response to these single-pulse stimuli could be enhanced for a long period of time if he first delivered a high-frequency train of stimuli to the presynaptic fibers. When such a train of stimuli was applied, subsequent single-pulse stimuli elicited stronger, prolonged EPSPs in the postsynaptic cell population. This phenomenon, whereby a high-frequency stimulus could produce a long-lived enhancement in the postsynaptic cells' response to subsequent single-pulse stimuli, was initially called "long-lasting potentiation".

Timothy Bliss, who joined the Andersen laboratory in 1968, collaborated with Lømo and in 1973 the two published the first characterization of long-lasting potentiation in the rabbit hippocampus. Bliss and Tony Gardner-Medwin published a similar report of long-lasting potentiation in the awake animal which appeared in the same issue as the Bliss and Lømo report. In 1975, Douglas and Goddard proposed "long-term potentiation" as a new name for the phenomenon of long-lasting potentiation. Andersen suggested that the authors chose "long-term potentiation" perhaps because of its easily pronounced acronym, "LTP".

Models and theory
The physical and biological mechanism of LTP is still not understood, but some successful models have been developed. Studies of dendritic spines, protruding structures on dendrites that physically grow and retract over the course of minutes or hours, have suggested a relationship between the electrical resistance of the spine and the effective synapse strength, due to their relationship with intracellular calcium transients. Mathematical models such as BCM Theory, which depends also on intracellular calcium in relation to NMDA receptor voltage gates, have been developed since the 1980s and modify the traditional a priori Hebbian learning model with both biological and experimental justification. Still, others have proposed re-arranging or synchronizing the relationship between receptor regulation, LTP, and synaptic strength.

Types
Since its original discovery in the rabbit hippocampus, LTP has been observed in a variety of other neural structures, including the cerebral cortex, cerebellum, amygdala, and many others. Robert Malenka, a prominent LTP researcher, has suggested that LTP may even occur at all excitatory synapses in the mammalian brain.

Different areas of the brain exhibit different forms of LTP. The specific type of LTP exhibited between neurons depends on a number of factors. One such factor is the age of the organism when LTP is observed. For example, the molecular mechanisms of LTP in the immature hippocampus differ from those mechanisms that underlie LTP of the adult hippocampus. The signalling pathways used by a particular cell also contribute to the specific type of LTP present. For example, some types of hippocampal LTP depend on the NMDA receptor, others may depend upon the metabotropic glutamate receptor (mGluR), while still others depend upon another molecule altogether. The variety of signaling pathways that contribute to LTP and the wide distribution of these various pathways in the brain are reasons that the type of LTP exhibited between neurons depends only in part upon the anatomic location in which LTP is observed. For example, LTP in the Schaffer collateral pathway of the hippocampus is NMDA receptor-dependent - this was proved by the application of AP5, an antagonist to the NMDA receptor, which prevented LTP in this pathway. Conversely, LTP in the mossy fiber pathway is NMDA receptor-independent, even though both pathways are in the hippocampus.

The pre- and postsynaptic activity required to induce LTP are other criteria by which LTP is classified. Broadly, this allows classification of LTP into Hebbian, non-Hebbian, and anti-Hebbian mechanisms. Borrowing its name from Hebb's postulate, summarized by the maxim that "cells that fire together wire together," Hebbian LTP requires simultaneous pre- and postsynaptic depolarization for its induction. Non-Hebbian LTP is a type of LTP that does not require such simultaneous depolarization of pre- and postsynaptic cells; an example of this occurs in the mossy fiber hippocampal pathway. A special case of non-Hebbian LTP, anti-Hebbian LTP explicitly requires simultaneous presynaptic depolarization and relative postsynaptic hyperpolarization for its induction.

Owing to its predictable organization and readily inducible LTP, the CA1 hippocampus has become the prototypical site of mammalian LTP study. In particular, NMDA receptor-dependent LTP in the adult CA1 hippocampus is the most widely studied type of LTP, and is therefore, the focus of this article.

Properties
NMDA receptor-dependent LTP exhibits several properties, including input specificity, associativity, cooperativity, and persistence.

 * Input specificity
 * Once induced, LTP at one synapse does not spread to other synapses; rather LTP is input specific. Long-term potentiation is only propagated to those synapses according to the rules of associativity and cooperativity. However, the input specificity of LTP may be incomplete at short distances. One model to explain the input specificity of LTP was presented by Frey and Morris in 1997 and is called the synaptic tagging and capture hypothesis.

 * Associativity
 * Associativity refers to the observation that when weak stimulation of a single pathway is insufficient for the induction of LTP, simultaneous strong stimulation of another pathway will induce LTP at both pathways.

 * Cooperativity
 * LTP can be induced either by strong tetanic stimulation of a single pathway to a synapse, or cooperatively via the weaker stimulation of many. When one pathway into a synapse is stimulated weakly, it produces insufficient postsynaptic depolarization to induce LTP. In contrast, when weak stimuli are applied to many pathways that converge on a single patch of postsynaptic membrane, the individual postsynaptic depolarizations generated may collectively depolarize the postsynaptic cell enough to induce LTP cooperatively. Synaptic tagging, discussed later, may be a common mechanism underlying associativity and cooperativity. Bruce McNaughton argues that any difference between associativity and cooperativity is strictly semantic. Experiments performed by stimulating an array of individual dendritic spines, have shown that synaptic cooperativity by as few as two adjacent dendritic spines prevents long term depression (LTD) allowing only LTP.

 * Persistence
 * LTP is persistent, lasting from several minutes to many months, and it is this persistence that separates LTP from other forms of synaptic plasticity.

Maintenance
While induction entails the transient activation of CaMKII and PKC, maintenance of E-LTP (early-form LTP) is characterized by their persistent activation. During this stage, PKMz (Protein kinase Mζ) which does not have dependence on calcium, become autonomously active. Consequently, they are able to carry out the phosphorylation events that underlie E-LTP expression.

Expression
Phosphorylation is a chemical reaction in which a small phosphate group is added to another molecule to change that molecule's activity. Autonomously active CaMKII and PKC use phosphorylation to carry out the two major mechanisms underlying the expression of E-LTP. First, and most importantly, they phosphorylate existing AMPA receptors to increase their activity. Second, they mediate or modulate the insertion of additional AMPA receptors into the postsynaptic membrane. Importantly, the delivery of AMPA receptors to the synapse during E-LTP is independent of protein synthesis. This is achieved by having a nonsynaptic pool of AMPA receptors adjacent to the postsynaptic membrane. When the appropriate LTP-inducing stimulus arrives, nonsynaptic AMPA receptors are rapidly trafficked into the postsynaptic membrane under the influence of protein kinases. As mentioned previously, AMPA receptors are the brain's most abundant glutamate receptors and mediate the majority of its excitatory activity. By increasing the efficiency and number of AMPA receptors at the synapse, future excitatory stimuli generate larger postsynaptic responses.

While the above model of E-LTP describes entirely postsynaptic mechanisms for induction, maintenance, and expression, an additional component of expression may occur presynaptically. One hypothesis of this presynaptic facilitation is that persistent CaMKII activity in the postsynaptic cell during E-LTP may lead to the synthesis of a "retrograde messenger", discussed later. According to this hypothesis, the newly synthesized messenger travels across the synaptic cleft from the postsynaptic to the presynaptic cell, leading to a chain of events that facilitate the presynaptic response to subsequent stimuli. Such events may include an increase in neurotransmitter vesicle number, probability of vesicle release, or both. In addition to the retrograde messenger underlying presynaptic expression in early LTP, the retrograde messenger may also play a role in the expression of late LTP.

Late phase

Late LTP (L-LTP) is the natural extension of E-LTP. Unlike E-LTP, which is independent of protein synthesis, L-LTP requires gene transcription and protein synthesis in the postsynaptic cell. Two phases of L-LTP exist: the first depends upon protein synthesis, while the second depends upon both gene transcription and protein synthesis. These phases are occasionally called LTP2 and LTP3, respectively, with E-LTP referred to as LTP1 under this nomenclature.

Induction
Late LTP is induced by changes in gene expression and protein synthesis brought about by the persistent activation of protein kinases activated during E-LTP, such as MAPK. In fact, MAPK—specifically the extracellular signal-regulated kinase (ERK) subfamily of MAPKs—may be the molecular link between E-LTP and L-LTP, since many signaling cascades involved in E-LTP, including CaMKII and PKC, can converge on ERK. Recent research has shown that the induction of L-LTP can depend on coincident molecular events, namely PKA activation and calcium influx, that converge on CRTC1 (TORC1), a potent transcriptional coactivator for cAMP response element binding protein (CREB). This requirement for a molecular coincidence accounts perfectly for the associative nature of LTP, and, presumably, for that of learning.

Maintenance
Upon activation, ERK may phosphorylate a number of cytoplasmic and nuclear molecules that ultimately result in the protein synthesis and morphological changes observed in L-LTP. These cytoplasmic and nuclear molecules may include transcription factors such as CREB. ERK-mediated changes in transcription factor activity may trigger the synthesis of proteins that underlie the maintenance of L-LTP. One such molecule may be protein kinase Mζ (PKMζ), a persistently active kinase whose synthesis increases following LTP induction. PKMζ is an atypical isoform of PKC that lacks a regulatory subunit and thus remains constitutively active. Unlike other kinases that mediate LTP, PKMζ is active not just in the first 30 minutes following LTP induction; rather, PKMζ becomes a requirement for LTP maintenance only during the late phase of LTP. PKMζ thus appears important for the persistence of memory and would be expected to be important in the maintenance of long-term memory. Indeed, administration of a PKMζ inhibitor into the hippocampus of the rat results in retrograde amnesia with intact short-term memory; PKMζ does not play a role in the establishment of short-term memory. PKMζ has recently been shown to underlie L-LTP maintenance by directing the trafficking and reorganization of proteins in the synaptic scaffolding that underlie the expression of L-LTP. Even more recently, transgenic mice lacking PKMζ demonstrate normal LTP, questioning the necessity of PKMζ.

The long-term stabilization of synaptic changes is also determined by a parallel increase of pre- and postsynaptic structures such as axonal bouton, dendritic spine and postsynaptic density. On the molecular level, an increase of the postsynaptic scaffolding proteins PSD-95 and Homer1c has been shown to correlate with the stabilization of synaptic enlargement.

Expression
The identities of only a few proteins synthesized during L-LTP are known. Regardless of their identities, it is thought that they contribute to the increase in dendritic spine number, surface area, and postsynaptic sensitivity to neurotransmitter associated with L-LTP expression. The latter may be brought about in part by the enhanced synthesis of AMPA receptors during L-LTP. Late LTP is also associated with the presynaptic synthesis of synaptotagmin and an increase in synaptic vesicle number, suggesting that L-LTP induces protein synthesis not only in postsynaptic cells, but in presynaptic cells as well. As mentioned previously, for postsynaptic LTP induction to result in presynaptic protein synthesis, there must be communication from the postsynaptic to the presynaptic cell. This may occur via the synthesis of a retrograde messenger, discussed later.

Even in studies restricted to postsynaptic events, investigators have not determined the location of the protein synthesis that underlies L-LTP. Specifically, it is unclear whether protein synthesis takes place in the postsynaptic cell body or in its dendrites. Despite having observed ribosomes (the major components of the protein synthesis machinery) in dendrites as early as the 1960s, prevailing wisdom was that the cell body was the predominant site of protein synthesis in neurons. This reasoning was not seriously challenged until the 1980s, when investigators reported observing protein synthesis in dendrites whose connection to their cell body had been severed. More recently, investigators have demonstrated that this type of local protein synthesis is necessary for some types of LTP.

One reason for the popularity of the local protein synthesis hypothesis is that it provides a possible mechanism for the specificity associated with LTP. Specifically, if indeed local protein synthesis underlies L-LTP, only dendritic spines receiving LTP-inducing stimuli will undergo LTP; the potentiation will not be propagated to adjacent synapses. By contrast, global protein synthesis that occurs in the cell body requires that proteins be shipped out to every area of the cell, including synapses that have not received LTP-inducing stimuli. Whereas local protein synthesis provides a mechanism for specificity, global protein synthesis would seem to directly compromise it. However, as discussed later, the synaptic tagging hypothesis successfully reconciles global protein synthesis, synapse specificity, and associativity.

Retrograde signaling
Retrograde signaling is a hypothesis that attempts to explain that, while LTP is induced and expressed postsynaptically, some evidence suggests that it is expressed presynaptically as well. The hypothesis gets its name because normal synaptic transmission is directional and proceeds from the presynaptic to the postsynaptic cell. For induction to occur postsynaptically and be partially expressed presynaptically, a message must travel from the postsynaptic cell to the presynaptic cell in a retrograde (reverse) direction. Once there, the message presumably initiates a cascade of events that leads to a presynaptic component of expression, such as the increased probability of neurotransmitter vesicle release.

Retrograde signaling is currently a contentious subject as some investigators do not believe the presynaptic cell contributes at all to the expression of LTP. Even among proponents of the hypothesis there is controversy over the identity of the messenger. Early thoughts focused on nitric oxide, while most recent evidence points to cell adhesion proteins.

Synaptic tagging
Before the local protein synthesis hypothesis gained significant support, there was general agreement that the protein synthesis underlying L-LTP occurred in the cell body. Further, there was thought that the products of this synthesis were shipped cell-wide in a nonspecific manner. It thus became necessary to explain how protein synthesis could occur in the cell body without compromising LTP's input specificity. The synaptic tagging hypothesis attempts to solve the cell's difficult problem of synthesizing proteins in the cell body but ensuring they only reach synapses that have received LTP-inducing stimuli.

The synaptic tagging hypothesis proposes that a "synaptic tag" is synthesized at synapses that have received LTP-inducing stimuli, and that this synaptic tag may serve to capture plasticity-related proteins shipped cell-wide from the cell body. Studies of LTP in the marine snail Aplysia californica have implicated synaptic tagging as a mechanism for the input-specificity of LTP. There is some evidence that given two widely separated synapses, an LTP-inducing stimulus at one synapse drives several signaling cascades (described previously) that initiates gene expression in the cell nucleus. At the same synapse (but not the unstimulated synapse), local protein synthesis creates a short-lived (less than three hours) synaptic tag. The products of gene expression are shipped globally throughout the cell, but are only captured by synapses that express the synaptic tag. Thus only the synapse receiving LTP-inducing stimuli is potentiated, demonstrating LTP's input specificity.

The synaptic tag hypothesis may also account for LTP's associativity and cooperativity. Associativity (see Properties) is observed when one synapse is excited with LTP-inducing stimulation while a separate synapse is only weakly stimulated. Whereas one might expect only the strongly stimulated synapse to undergo LTP (since weak stimulation alone is insufficient to induce LTP at either synapse), both synapses will in fact undergo LTP. While weak stimuli are unable to induce protein synthesis in the cell body, they may prompt the synthesis of a synaptic tag. Simultaneous strong stimulation of a separate pathway, capable of inducing cell body protein synthesis, then may prompt the production of plasticity-related proteins, which are shipped cell-wide. With both synapses expressing the synaptic tag, both would capture the protein products resulting in the expression of LTP in both the strongly stimulated and weakly stimulated pathways.

Cooperativity is observed when two synapses are activated by weak stimuli incapable of inducing LTP when stimulated individually. But upon simultaneous weak stimulation, both synapses undergo LTP in a cooperative fashion. Synaptic tagging does not explain how multiple weak stimuli can result in a collective stimulus sufficient to induce LTP (this is explained by the postsynaptic summation of EPSPs described previously). Rather, synaptic tagging explains the ability of weakly stimulated synapses, none of which are capable of independently generating LTP, to receive the products of protein synthesis initiated collectively. As before, this may be accomplished through the synthesis of a local synaptic tag following weak synaptic stimulation.

Modulation
As described previously, the molecules that underlie LTP can be classified as mediators or modulators. A mediator of LTP is a molecule, such as the NMDA receptor or calcium, whose presence and activity is necessary for generating LTP under nearly all conditions. By contrast, a modulator is a molecule that can alter LTP but is not essential for its generation or expression.

In addition to the signaling pathways described above, hippocampal LTP may be altered by a variety of modulators. For example, the steroid hormone estradiol may enhance LTP by driving CREB phosphorylation and subsequent dendritic spine growth. Additionally, β-adrenergic receptor agonists such as norepinephrine may alter the protein synthesis-dependent late phase of LTP. Nitric oxide synthase activity may also result in the subsequent activation of guanylyl cyclase and PKG. Similarly, activation of dopamine receptors may enhance LTP through the cAMP/PKA signaling pathway.

Relationship to behavioral memory
While the long-term potentiation of synapses in cell culture seems to provide an elegant substrate for learning and memory, the contribution of LTP to behavioral learning — that is, learning at the level of the whole organism — cannot simply be extrapolated from in vitro studies. For this reason, considerable effort has been dedicated to establishing whether LTP is a requirement for learning and memory in living animals. Because of this, LTP also plays a crucial role in fear processing.

Spatial memory

In 1986, Richard Morris provided some of the first evidence that LTP was indeed required for the formation of memories in vivo. He tested the spatial memory of rats by pharmacologically modifying their hippocampus, a brain structure whose role in spatial learning is well established. Rats were trained on the Morris water maze, a spatial memory task in which rats swim in a pool of murky water until they locate the platform hidden beneath its surface. During this exercise, normal rats are expected to associate the location of the hidden platform with salient cues placed at specific positions around the circumference of the maze. After training, one group of rats had their hippocampi bathed in the NMDA receptor blocker APV, while the other group served as the control. Both groups were then subjected to the water maze spatial memory task. Rats in the control group were able to locate the platform and escape from the pool, while the performance of APV-treated rats was significantly impaired. Moreover, when slices of the hippocampus were taken from both groups, LTP was easily induced in controls, but could not be induced in the brains of APV-treated rats. This provided early evidence that the NMDA receptor — and by extension, LTP — was required for at least some types of learning and memory.

Similarly, Susumu Tonegawa demonstrated in 1996 that the CA1 area of the hippocampus is crucial to the formation of spatial memories in living mice. So-called place cells located in this region become active only when the rat is in a particular location — called a place field — in the environment. Since these place fields are distributed throughout the environment, one interpretation is that groups of place cells form maps in the hippocampus. The accuracy of these maps determines how well a rat learns about its environment and thus how well it can navigate it. Tonegawa found that by impairing the NMDA receptor, specifically by genetically removing the NR1 subunit in the CA1 region, the place fields generated were substantially less specific than those of controls. That is, mice produced faulty spatial maps when their NMDA receptors were impaired. As expected, these mice performed very poorly on spatial tasks compared to controls, further supporting the role of LTP in spatial learning.

Enhanced NMDA receptor activity in the hippocampus has also been shown to produce enhanced LTP and an overall improvement in spatial learning. In 1999, Tang et al. produced a line of mice with enhanced NMDA receptor function by overexpressing the NR2B subunit in the hippocampus. The resulting smart mice, nicknamed "Doogie mice" after the fictional prodigious doctor Doogie Howser, had larger LTP and excelled at spatial learning tasks, reinforcing LTP's importance in the formation of hippocampus-dependent memories.

Inhibitory avoidance
In 2006, Jonathan Whitlock and colleagues reported on a series of experiments that provided perhaps the strongest evidence of LTP's role in behavioral memory, arguing that to conclude that LTP underlies behavioral learning, the two processes must both mimic and occlude one another. Employing an inhibitory avoidance learning paradigm, researchers trained rats in a two-chambered apparatus with light and dark chambers, the latter being fitted with a device that delivered a foot shock to the rat upon entry. An analysis of CA1 hippocampal synapses revealed that inhibitory avoidance training induced in vivo AMPA receptor phosphorylation of the same type as that seen in LTP in vitro; that is, inhibitory avoidance training mimicked LTP. In addition, synapses potentiated during training could not be further potentiated by experimental manipulations that would have otherwise induced LTP; that is, inhibitory avoidance training occluded LTP. In a response to the article, Timothy Bliss and colleagues remarked that these and related experiments "substantially advance the case for LTP as a neural mechanism for memory."

Clinical significance
The role of LTP in disease is less clear than its role in basic mechanisms of synaptic plasticity. However, alterations in LTP may contribute to a number of neurological diseases, including depression, Parkinson's disease, epilepsy, and neuropathic pain. Impaired LTP may also have a role in Alzheimer's disease and drug addiction.

Alzheimer's disease

LTP has received much attention among those who study Alzheimer's disease (AD), a neurodegenerative disease that causes marked cognitive decline and dementia. Much of this deterioration occurs in association with degenerative changes in the hippocampus and other medial temporal lobe structures. Because of the hippocampus' well established role in LTP, some have suggested that the cognitive decline seen in individuals with AD may result from impaired LTP.

In a 2003 review of the literature, Rowan et al. proposed one model for how LTP might be affected in AD. AD appears to result, at least in part, from misprocessing of amyloid precursor protein (APP). The result of this abnormal processing is the accumulation of fragments of this protein, called amyloid β (Aβ). Aβ exists in both soluble and fibrillar forms. Misprocessing of APP results in the accumulation of soluble Aβ that, according to Rowan's hypothesis, impairs hippocampal LTP and may lead to the cognitive decline seen early in AD.

AD may also impair LTP through mechanisms distinct from Aβ. For example, one study demonstrated that the enzyme PKMζ accumulates in neurofibrillary tangles, which are a pathologic marker of AD. PKMζ is an enzyme with critical importance in the maintenance of late LTP.

Drug addiction
Research in the field of addiction medicine has also recently turned its focus to LTP, owing to the hypothesis that drug addiction represents a powerful form of learning and memory. Addiction is a complex neurobehavioral phenomenon involving various parts of the brain, such as the ventral tegmental area (VTA) and nucleus accumbens (NAc). Studies have demonstrated that VTA and NAc synapses are capable of undergoing LTP and that this LTP may be responsible for the behaviors that characterize addiction.

title: Long-term potentiation