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Talk:Stained glass

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Images
Arpingstone, you actually like the all-images-on-right look? I think the old layout looked much better. – Quadell (talk) (help)  22:19, Oct 3, 2004 (UTC)

 * The reason for the change was that on my 1024 by 768 screen one pic was stuck horizontally against another (hard to describe it!) so most were on the right but one was out of place. It seems that what looks good on your screen looks terrible on mine. So to make the article look good for everyone a simple right-column is sometimes the only choice because the ideal situation of a left-right alternation doesn't work. If you don't like what I've done, just revert, I don't mind - Adrian Pingstone 22:34, 3 Oct 2004 (UTC)

Painted stained glass
There is no mention of the common habit of farting detail (e.g. faces) onto stained glass. Is that because it is a different craft, or just an omission? Notinasnaid 11:22, 19 Oct 2004 (UTC)

Largest collection
Does anyone know what the largest collection of stained glass is? Number of windows in a building, for example. CoolGuy 08:38, 2 Dec 2004 (UTC)

Painted glass: a separate thing or a misnomer?
Painted glass is mentioned here in the "See also" section, but it's redirected to the article itself. There are two more articles linking to painted glass: Oliver Cromwell and Lillafüred. Is there really such a thing as a painted glass different from stained glass? If so, it should be clarified at least in a stub how they relate to each other (instead of the redirect). If not, and it's a misnomer, links to painted glass should be replaced by stained glass, I suppose. -- Adam78 00:03, 27 Jun 2005 (UTC)

Stained verses painted

Actually, the term "Stained" refers to a process developed by the Germans in the 14th century. Silver nitrate was mixed with a binder and painted on the reverse side of the "trace line" and "matted" side of the glass, then fired at a lower temperature, 1180 degrees F., the medium (binder) is then washed off to reveal the yellow or golden color "stain". The trace line and mattes (mattes are applied as a thin even coat and then selective areas are removed with brushes to create highlights, fired at 1275F, roughly)) The glass is, truly, "stained" by the silver nitrate and allowed the Medieval artists to achieve 2 colors therefore greater versatility with a single piece of clear glass to describe architectural, clothing pattern, or other details. As well, minor correction: Glass is sold by the square foot by some manufacturers, and by the pound by others.

Jane Jacobson, Glass Roots Studio, Oct 23, 2005

Jim Gary?
On April 15, 2006, user 63.232.117.214 added under "See also": * Sculpture ** Jim Gary

However, the article on Jim Gary mentions nothing about glass. Does he indeed work with stained glass?

RickP 06:51, 16 April 2006 (UTC)

 * Yes, American sculptor Jim Gary made many -- life-sized figures -- of stained glass. He also created many other, smaller stained glass sculptures. It was a material he returned to frequently in his career. Discussion of his stained glass work was put in the Wikipedia article on him, but was removed by a wiki administrator, haro. The extensive history of the article recorded in the talk and edits, documents the struggles of contributors who seem to have given up fighting off "the administrator". There are many photographs of large stained glass sculptures by Gary in the early biography of him that is still available on the Internet through used book sellers. It is, Jim Gary: his life and art by Tova Navarra, which was published in 1987 by HFN, Inc. His official web site is still very active and his studio director is quite accessible if you have any questions. Many photographs of this work used to be posted on the Internet, but the sites have changed what they feature. As someone interested in his work for a long time, I have had many questions about his sculpture answered quickly through the official site. It looks as if the long and detailed original article, was contributed by Jim Gary's studio director right after he died. The article now has been slashed down to a sketchy stub -- unfortunately -- — Preceding unsigned comment added by 63.232.16.27 (talk) 12:34, 30 April 2006 (UTC)
 * Thanks for the answer. A few words in the Jim Gary article about this would be appreciated. Any chance of uploaded copyright-free images of his stained glass work to commons? RickP 20:35, 30 April 2006 (UTC)
 * It's a pity: the article was large, and while it was certainly a bit uncritical, the editorial response was to simply delete all but a stub. This doesn't really encourage new editors. Or old ones. Notinasnaid 20:39, 30 April 2006 (UTC)
 * contacted Jim Gary's studio director, who has photographs, but I do not know how to upload a photograph to Wikipedia, nor whether it then becomes the property of Wikipedia -- she is reluctant to provide them or write anything in the article given the treatment of the new editors who have tried to make it a good entry... (can't blame her, she can post to her own site without such interference). Want to tackle it yourself with the material provided in this article and talk? Perhaps the obsessed administrator, a bully monitoring the site at the expense of the new contributors would act differently to established editors. -- who knows? -- I might be able to get the studio director send you materials you need if it works out, or you could contact her directly. LMK — Preceding unsigned comment added by 63.233.126.210 (talk) 22:12, 3 May 2006 (UTC)
 * Was the other editor an administrator? Photos must be either public domain or released under a license that allows any use, including commercial, with a credit. Notinasnaid 09:11, 4 May 2006 (UTC)
 * The id for the administrator who kept reverting only to his edits, is listed as harro 5 (all one word). His rigidity is confusing because, looking at the Wikipedia regulations, allowing a great deal of editorial freedom is expressed along with a Wikipedia statement that nothing is established to prevent different styles. Curiously, he made no attempt to make any edits except deletions -- so he did _ nothing _ to contribute to the article, seeming only interested in preventing others from the freedoms they ought to have had -- don't understand the motivation. I will see whether a credit would be okay for a good photograph of one of his stained glass figures -- would that just be a (c) notation or some indication such as, courtsey of... ? I have seen notes accompanying some photographs here that indicate the use is only for the article, not any other use... what are the rules for those? That might be better to offer. LMK — Preceding unsigned comment added by 63.158.184.35 (talk) 11:52, 5 May 2006 (UTC)
 * Interestingly, the bulk deletion of most of the article was not done by the admininstrator you name, but someone anonymous. So, following Wikipedia's recommendations, I have been bold and put it back, so it can be improved into the great article it can be. So, editors, please come back and have a go at it. See Talk:Jim Gary Notinasnaid 14:52, 5 May 2006 (UTC)
 * bold and brilliant -- let's see if your action promotes co-operation on the article! It may take a while, but am glad to see your effort. Regarding the stained glass figure, how do I ask for the photograph credit format? LMK — Preceding unsigned comment added by 63.232.1.65 (talk) 00:30, 6 May 2006 (UTC)

examples of windows needed
An article about windows should include examples. All the examples are modern. We need examples of mediaeval and Victorian stained glass. I tried to put something in about a period, ie the 19th. century when there was a huge amount of glass put in both in the UK and USA, but of which there is not much record. Many of the firms have perished leaving no records. I put in a good deal of what I know but did not include too much for fear of unbalancing the article. If anyone knows how to include availabel pix of windows, please do. I have some good windows in our church and will include them if no one else does. OK? Roger Arguile June 6th 2006 3.40 pm (UTC)

Reformation
In the section discussing the reformation the article states that "Few [windows] remain undamaged." This needs some context. Does this mean only in Britain? In all Protestant areas? Throughout Europe? - SimonP 01:42, 19 May 2006 (UTC)

Desg
In making a small addition and putting in a link to a commercial site, you also lost a large part of the article, in fact everything below your own addition. You need to check carefully by using the 'show preview' option before saving.

I have removed your link to the nice little window in a dear little weatherboard church that took us straight to the commercial site.

Firstly, the heading that you put it under pertained to the greatest examples of stained glass in the world, eg Chartres Cathedral. Your example is hardly one that a person would travel ten thousand miles to see.

Secondly, Wikipedia isn't the place for advertising.

--Amandajm 21:29, 13 September 2006 (UTC)

I removed the link to the small forum "stainedglassville.com" added by Desg. This is another of his commercial sites.

--RogerJ 21:29, 15 September 2006 (UTC)

Desg returned to re-insert the link to the "nice little window in a dear little weatherboard church" with the link to the commercial site, as well as the link to his newly formed commercial forum.

Similar additions of his commercial links on the "Lead came and copper foil glasswork" Wiki page have been removed.

A very good link to the Preservation of Stained Glass was removed by Desg, which he replaced with a link to his forum. The original link was restored. Similar behavior (replacing a pre-existing link with his own) was also observed and fixed on the "Lead came and copper foil glasswork" page.

--RogerJ 16:48, 16 September 2006 (UTC) I have corrected the links and will point out that the preservation link went to nothing to do with glass. The memorial dove window you speak of is visited by many to a very historical location with a single chapel. Mention of this work in "Stained Glass" is quite appropriate in relation to memorial windows. I am new to Wiki and am clear as to the rules. I have removed the commercial link for web-o-rama as it is relative to your guidelines. Thank you, DESG
 * The preservation link has as its title, and I quote, "The Preservation and Repair of Historic Stained and Leaded Glass." Are you sure you were following the link correctly? It links directly to the Technical Preservation Services of the U.S. Department of Interior, and has a very comprehensive writeup concerning stained glass, difficulties with preservation, etc. I was willing to believe you at first... but this strains credulity. I would urge you to please click on links before you remove them, especially since you seem to be having difficulty with Wikipedia's external links policy. Captainktainer * Talk 15:58, 17 September 2006 (UTC)
 * I urge you again to read the link provided. From the page: "This Brief gives a short history of stained and leaded glass in America. It also surveys basic preservation and documentation issues facing owners of buildings with leaded glass. It addresses common causes of deterioration and presents repair, restoration, and protection options. Captainktainer * Talk 16:01, 17 September 2006 (UTC)

I am willing to check it again. I have before and it goes to the National Park service. If the artical you speek of is there I will link to it correctly. DESG

I have checked the link again and it points to under rule #5 the link doesn't support all operating systems. Check with the administrators or host of the web page to see why there is a redirection. I have looked deeper into the site and found the stained glass article but only after jumping through a few hoops.

Additional stained glass resources
However, it is also the only "source" remaining for the article. Your quote seems a bit short of fact. Have you even read my tutorial pages? stained glass art tips If so you will see alot of additional professional advice on the subject. Please consider inclusion or not deleting the valuable resource when it is reinstated, Thank you Desg 03:06, 19 September 2006 (UTC)

Vidimus Magazine
T'm not in favour of deleting this link, so I've reinstated it. I think we ought to be patient and see what Vidimus come up with, as it's the first monthly publication, and the article on the featured panel is very detailed and the photo very clear, illustrating some of the subject matter of our present article, likethe use of yellow stain etc. It seems a pity to be so hardline with an accademic, non-commercial publication!

--Amandajm 12:46, 16 November 2006 (UTC)

I disagree. While the link is not objectionable, it is not worthy of being a reference in the WIkipedia article. Let's check again in 6 months to a year, before reinstating. RogerJ 19:05, 1 December 2006 (UTC)

Removal of additions to intro
Just to explain my self-

I've just removed several lines that were recently inserted in the intro. The bit about metal salts repeated what had already been written, about two lines above it. The description of the fact that the gLass gets cut into pieces is all there under the heading Technical. The person (no user name) obviously hadn't read the whole long detailed description before editting the brief summary. In other words, it was superfluous.

--Amandajm 09:41, 14 December 2006 (UTC) 09:39, 14 December 2006 (UTC)

Re Removal of new pictures
All those new pictures are beautiful and will be useful somewhere.... But

 * We've tried to keep this article fairly tightly constructed, but it's well over the usual length because it's a very big subject.
 * Every pic that is in place has been selected for a purpose.
 * Having 5 pictures in a small gallery looks bad. That's why there's only four in each.
 * I've put the new pics into the gallery at the bottom, and will remove them into appropriate articles at a later date.
 * please see what's already in place! In a gallery of 4 pics there was already a pic from the Morris studio. Didn't need two! There was already an excellent alabaster window. Didn't need two of those either.

--Amandajm 13:57, 29 January 2007 (UTC)

Reading stained glass
There was a comment posted that said that this site doesn't tell you how to read stained glass.

The reason for that is that there is a maximum desirable size for a Wikipedia article. This article already exceeds that size.

"Reading" artworks such as stained glass is a whole subject in itself. You can find some of the answers under Poor Man's Bible. You can also look up Iconography. There is another interesting and useful page called Tree of Jesse.

--Amandajm 10:09, 1 March 2007 (UTC)

 * Perhaps this can be put into its own article, with a link from the "See Also" section. In fact, I see that there is already one such article on another stained-glass subject — Stained glass - British glass, 1811-1918. (A similar-looking link, Stained glass artists, is also listed, but is a redirect to a category.)
 * But I highly doubt there's a set-in-stone limit on the number of "sub-articles". Joan of Arc, for example, has six: Trial of Joan of Arc, Cultural depictions of Joan of Arc, and Canonization of Joan of Arc cover just half of the Joan-of-Arc subjects that have been expanded into their own articles. — AnnaKucsma   (Talk to me!) 20:51, 27 April 2007 (UTC)

Stained Grass
Not a mistake. Green glass has been around for a very long time.....bottles, OK? But to create an appearance of green grass, blue glass was often stained with yellow, because the effect was more natural.

--Amandajm 08:26, 27 April 2007 (UTC)

We would like to add a link in the 'external links' section
One of my friends has asked me to add a link of her website the Staint Glass Wiki site under 'external links' but I saw it should be verified first. Her website shows some fine examples of stained glass windows in churches particularly in Derbyshire, Nottinghamshire and Lincolnshire by Charles E Kempe, Clayton and Bell, William Morris, Edward Burne-Jones and Henry Holiday the latter three being Pre-Raphaelite stained glass window designers. They can be viewed at Magnificent Windows which is a photographic website showing the beauty and art form of stained glass. Please can you let me know if I can add the link to the Stained Glass Wiki site. Thanks! --Posiebers 23:08, 11 July 2007 (UTC)
 * Thankks for the request. I took a look at the site and it has some very nice photos of mainly 19th century windows. Would you please add the link to a different articl?Stained glass - British glass, 1811-1918

Also, in order to give accurate information, in association with an encyclopedic article, could you ask your friend to correct the introduuction that says that stained glass is probably one of the oldest crafts. Ask you friend to think about the stone tools made by prehistoric people, followed by making string, potting clay, weaving baskets, carving wood, making bone needles and fishhooks, spinning wool etc etc. These are all crafts (and we haven't even got to metalwork yet)! The oldest stained glass window in existence is only 1100 years old. That makes stained glass quite a new craft, in the history of humanity.

--Amandajm 00:30, 12 July 2007 (UTC)

I'd like to add an external link to the Victoria and Albert Museum's Sacred Stained Glass pages from this article. These pages feature different pieces of stained glass in the V&A's collection and the stories accompanying them, as well as giving information about the saints featured in stained glass. They also feature a short video on making stained glass. I hope this link will be considered, I think it contains lots of interesting information for those interested in stained glass. Many thanks VAwebteam 10:47, 5 August 2007 (UTC)

 * Good idea! The V&A has a great collection. --Amandajm 11:10, 5 August 2007 (UTC)

Scope of this page
Stained glass is an art craft. This page seems to be centered around architectural, religious stained glass panels, which is one, narrow field of this craft. I submit that this page should be a more generic page about the craft/art of stained glass and the specific panel/church/architectural aspect of stained glass be outlined on a separate page. Note that some people are trying to equate "stained glass" exclusively with architectural flat panels and this is inappropriate. --Mabu2 05:41, 25 September 2007 (UTC) moved to bottom of page by Amandajm 11:47, 25 September 2007 (UTC)

In response to this complaint
The writer of this added a short section, between the intro and the description of the making of stained glass windows, which I removed because it pertained directly to Lead came and copper foil glasswork which has its own page.

About the use of the term "stained glass" "Stained glass", the craft of creating it and the artworks thus produced have for the last thousand years been associated with church windows and the windows of other buildings such as town halls and universities. Throughout the nineteenth and most of the twentieth century, no producer of ordinary domestic leadlight windows would have advertised as a "stained glass" artist. Leadlighters were leadlighters. The notion that the creation of architectural flat panels "is one, narrow field of this craft" is ludicrous. The major works in this craft, be they in church buildings, railway stations or office blocks, are architectural panels, though nowadays, with slab glass and the like, not nnecessarily flat.

There is currently a trend to refer to anything created with lead or copper foil and coloured glass as "stained glass art" and equate it with the making of large stained glass windows. This would have brought howls of laughter from the team who designed and created the east window of Gloucester Cathedral.

This page is already very long, and a merger with all the very many articles that describe aspects of the craft is not really appropriate. What is here is pertains to that which has always been called stained glass, ie windows in churches and other significant buildings, a very demanding and often very large-scale craft that has been practised in Europe since the 10th century. Many of the stained glass windows referred to here and pictured here are supreme artistic creations.

There are articles on Leadlight, Cathedral glass (which is not glass in cathedrals), Faberge and the various glasses that he created, Art glass, Architectural glass and so on. It is really not a good idea to combine them. Besides, an article that deals with lead came and copper foil work is needed as a stand-alone article, because this is a significant modern craft that many people enjoy and are interested in.

I have suggested moving this page back to "Stained glass windows" which is where it was, I believe, once upon a time, but this met with poor response from the above apparently new editor.

The article was already about windows before I did a great deal of work on it. I am being accused of hijacking an article to a purpose, where in fact it seems that it is quite the other way around.

Amandajm 11:47, 25 September 2007 (UTC)

Intro
Rejigged the intro and incorporated some of the new material, plus mention of recent extension of the term to include things other than windows. Amandajm 12:47, 25 September 2007 (UTC)

 * I agree this article should remain essentially as it is, concentrated on the history of the design of major stained glass windows, with see also's and disam-ing as necessary. A move back to "stained glass window" I don't see as necessary, but it could be done. Johnbod 02:13, 27 September 2007 (UTC)
 * Agree with Amandajm for the reasons he's stated.  JGHowes talk  -  18:31, 27 September 2007 (UTC)

Moved this down It is clear that user Amandajm is acting like he "owns" this article and has a personal interest in maintaining control over it. This seems to be antithetical to the purpose of Wikipedia, and I contend that the term "Stained Glass" is generic and does not specifically apply to windows. Maybe a hundred years ago the term, "stained glass" may have had a more narrow interpretation, but not today. This article is narrow and should be under a different subheading such as Architectural stained glass or Stained glass windows. Furthermore, has anyone read this page in full? There are sections having nothing to do with stained glass; there are pictures of entirely different crafts such as vases and mosaics. And much of the article is a breakdown of history. This is not the kind of article that should be an entry point on a very wide and diverse field such as "Stained Glass." --Mabu2 05:32, 28 September 2007 (UTC)

 * Mabu2, please don't remove pictures from the article of things that are discussed within text of the article itself. Mabu2, you obviously haven't read the article yourself, or you would know why the vases are there. Can I suggest that you take a look at the page Stained glass artists and check out what it takes to be called an "artist" in the media of stained glass. I had nothing to do with setting up that page, although I have added names as I wrote articles.

 * Please understand as well, that there is a vandal who adds his own work to this page every day. If you find images at the foot of the page that are obviously inappropriate, they have been added by a vandal, who also deletes links to important websites in order to link to his own commercial concern. This is not allowed, but it happens all the time.

 * Amandajm 09:06, 28 September 2007 (UTC)

Stained glass schools
"Twentieth century .... Today there are a few academic establishments that teach the traditional skills. One of those establishments is Florida State University's Master Craftsman Program who recently completed the world's largest secular stained-glass windows installed in Bobby Bowden Field at Doak Campbell Stadium. More info at Master Craftsman Program" 1. The large window referred to doesn't appear to be a design worthy of mention in a short article (I can't find much of anything on the Web about it - the one image I found looked like a pretty amateurish design). Big isn't = to good. And I am quite skeptical that it is in fact the largest in the world - where is the source for that. How big is it in sq meters? There are some monster windows in Europe.

2. The statement that there are "few academic establishements" is misleading and provincial. If the statement is only referring to the US, maybe it is partly correct (but what about the Boston Museum School, and I am sure there are a number of others). But the US has never been the center of stained glass craft (or art). Europe has many schools that are far more significant and well-known than FSU, for example Swansea (one of four or five in England), and an even larger number exist in Germany and France.

Jon Romig —Preceding unsigned comment added by 68.165.81.50 (talk) 18:34, 20 November 2007 (UTC)

 * I don't know about the window,, but I agree entirely about the stained glass schools. Would you like to rewrite this section in a more appropriate way? Amandajm (talk) 02:46, 21 November 2007 (UTC)

Modern glass

 * A sentence was inserted between two sentences that were link. One sentence stated that new combinations of materials were use, the next one was about the development of slab glass. A sentence about etched glass was put between them, instead of at the end of the paragraph. Etched glass is not a "new development".

 * Etched glass isn't stained glass, even though it may be used by stained glass artists.

 * Leptat (registered trade name) is the brand name for a type of etched glass. It belongs on a page about etched glass. One has to be careful in writing about any registered product because Wiki is not the place for advertising.

 * Placement of pics. A good look at the page will tell the editor about the layout. Each section has been given four pics. No more, no less, because four fits into a single row across the page. That's the layout. All the other pics are added into a gallery at the bottom of the page. The examples at the bottom are not random. They have been chosen from hundreds that are available as being particularly good examples. Other good examples need to be ones that don't double-up. eg We don't need 4 William Morris windows or 6 Tiffany windows or 3 windows from Chartres.

 * If (and the source isn't cited) the recent slab glass window is the earliest in the US, then it is historically more signiificant thhan the Buckfast window, so I have put it in the gallery of four and moved Buckfast down.

Please cite the source for it being the earliest.

Amandajm (talk) 04:56, 5 March 2008 (UTC)

a stain glass window is made a long time ogo they where windows then they made them big into stian glass for churches —Preceding unsigned comment added by 71.248.140.144 (talk) 01:21, 10 September 2008 (UTC)

Reversals- explanation
"The term stained glass can refer to the material of coloured glass or the craft of working with it. Throughout its thousand-year history, the term "stained glass" was applied almost exclusively to the windows of churches, cathedrals, and other significant buildings. Although traditionally made in flat panels and used as windows, the creations of modern stained glass artists also include three-dimensional structures and sculpture.

Modern vernacular usage has often extended the term "stained glass" to include domestic leadlight and objets d'art created from lead came and copper foil glasswork such as exemplified in the famous lamps of Louis Comfort Tiffany."

The former is preferable to the latter since the words "stained glass" are not a quotation.
 * The words "The term" were deleted. They have been returned for reasons of grammar. One must either say "the term stained glass refers to (these two things)" or one must put the beginning words of the sentence into inverted commas : "Stained Glass" refers to.....

 * Stained glass sculpture is a new form. This is a difference in application.

 * Domestic leadlights and objets d'art are not new forms. They have been around for 150 years or more, but only recently have they been termed "stained glass". They are generally called "leadlight" or "copperfoil work". Up until the 1930s every town had a domestic leadlighter, who would never have referred to himself as a "stained glass artists". On the other hand, a modern sculptor working in stained glass, might very well be termed a "stained glass artist". That is the reason that I have returned that statement to the first paragraph, and made the paragraph about changing vernacular terminology a separate one.

Amandajm (talk) 13:44, 1 November 2008 (UTC)

 * Works for me. Thanks, Tom Harrison Talk 14:45, 1 November 2008 (UTC)

This is a very good article on British stained glass
But less so on that of the rest of the world 41.241.117.70 (talk) 19:06, 21 March 2009 (UTC)

 * I agree entirely. The information presented here about British glass is not necessary. There is a separate article. There should also be separate articles about French, German, Italian, US, and Australian stained glass. I believe a lot of stained glass was produce in Eastern Europe but I know absolutely nothing about it. Can anybody help? Amandajm (talk) 02:30, 22 March 2009 (UTC)

 * Problem fixed, I think that this is now a better balanced article. Certainly in terms of sections and pics, though a little wanting in text in some areas. Amandajm (talk) 00:27, 23 March 2009 (UTC)

The Stained Glass Association of America
The Stained Glass Association of America's stated purpose is to defend and protect the American form of stained glass art, as opposed to European. The former is said to be a different art form than the latter, using the materials themselves to elicit the art and allowing the patron to have his own thoughts about what he is observing while European stained glass uses the materials to paint a picture. When a studio attempts to join the society they are not allowed in if they are guilty of perpetrating the European style; a favored expression is "If you want a picture get a camera" and members are encouraged to tell church congregations asking for realistic painting on glass that this was a form used to tell the Christian story to illiterate congregants of old Europe and that the modern congregants of the church asking for such glass are more sophisticated than those Medieval European counterparts and can grasp abstract art and resent being treated as though dumb. In the eyes of this association stained glass studios and artists that deliver the European style of stained glass art to American architectural installations are persona non gratis in America and especially in the SGAA. Realistic pictorial windows make the association shudder as they are opposite the art form the group was established to protect, defend, and perpetrate as their ideal stained glass art. You say none of this here and it is their most important feature, not that they teach the art and restoration and preservation of it. They feature only the American style. It is believed by some artists who have a kiln and fire a piece of painted glass such as a face up to 35 times that this society is made up of studios and individual artists who don't know how or can't paint on glass as well as the Europeans of a century and more ago.While they say "No one does it any more",some others not belonging to the society say no one can do it any more, except some German and English artists who are highly trained through years of experience. Churches insuring such art in their windows are sometimes told by the insurance companies that if realistic painted windows are damaged an artist will have to be engaged from Europe and that it will be very expensive. This can be gleaned from looking through the organization's magazines from the 19-teens on, and their mission is clearly stated in the application for membership included in each magazine. The Conrad Schmidt studio has some very nice windows but none are done in the Munich or realistic style, the Medieval style, the Byzantine style and other European and pre-American styles of stained glass art.```` — Preceding unsigned comment added by 72.185.204.135 (talk) 12:54, 27 June 2012 (UTC)

 * The above comments are too much to place into the present article. I can assure you that there are many European stained glass artists working in a wide variety of styles and using techniques both ancient and modern. Within Europe there is a real need for glass conservators to maintain ancient techniques, and likewise for glass manufacturers to continue manufacturing glass by traditional methods as this is by far the best in restoration work.  Amandajm (talk) 16:20, 27 June 2012 (UTC)

Belcher
Would love to see a knowledgeable addition referring to the Belcher Mosaic Glass Company's work in the late nineteenth century. Belcher was an American company with a fairly unique style, short-lived because of worker safety concerns (and some other factors), but beautiful and for a time an example of an American esthetic. This company has been gone for well over a century, so there should be no advertising concerns. If this were deemed something that should have its own article, that would be fine, though I would think that it would be better as a brief segment in the larger stained glass article. I don't think I'm quite knowledgeable enough to write it... Xenophonix (talk) 02:53, 26 August 2014 (UTC)

Middle Eastern, Islamic & Asian Stained Glass
I came to this page hoping to read more about Iranian Orsi (aka Orosi) windows/stained glass... I was disappointed to notice this article is missing important details about Middle Eastern, Islamic and Asian stained glass history. It would be greatly appreciated if this article was less Western-centric. Jooojay (talk) 21:17, 19 January 2016 (UTC)

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photo added
Came to this page and noticed absence of any photos showing result of sunlight shining through stained glass window show added this photo. Please feel free to replace with more suitable photo Johnscotaus (talk) 07:59, 27 June 2016 (UTC)

Returned images
I have been off duty for a while. Came back and discovered that the gallery of Medieval glass had bee greatly reduced, with only one comment "to add emphasis". The glass of the Middle ages is the most renowned in the world. The examples had been chosen for their relevance, and to display a short history of an essentially visual media, not just an addition to the text.

Also, the examples of Spanish glass were all deplorable. The article needs picture of Spanish glass that match the quality of the images that are in the gallery above. A pic showing all the colours bleached out of clerestory windows does not illustrate anything about Spanish medieval glass. Amandajm (talk) 18:09, 13 August 2018 (UTC)

A Commons file used on this page has been nominated for deletion
The following Wikimedia Commons file used on this page has been nominated for deletion: Participate in the deletion discussion at the nomination page. —Community Tech bot (talk) 13:18, 3 November 2018 (UTC)
 * Fenster im Staatsrat 3.jpg

A Commons file used on this page has been nominated for deletion
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 * Chalour.jpg

A Commons file used on this page or its Wikidata item has been nominated for deletion
The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion: Participate in the deletion discussion at the nomination page. —Community Tech bot (talk) 00:28, 23 January 2021 (UTC)
 * Stained Glass Window, Church of Our Lady, Koblenz - Germany..jpg

"the Collegiate of Romont Switzerland"
This phrase was used in describing the location of a window. The term "collegiate" is unclear to me. I thought to wikilink it to another article, but was unable to confidently identify the appropriate article that used the word "collegiate". I hope a knowledgeable person will wikilink it to appropriate article. Pete unseth (talk) 13:15, 9 August 2022 (UTC)

Wiki Education assignment: Modern Latin America
— Assignment last updated by Katherine.Holt (talk) 19:09, 9 March 2023 (UTC)

title: Talk:Stained glass


text:
Wallerian degeneration

Wallerian degeneration is an active process of degeneration that results when a nerve fiber is cut or crushed and the part of the axon distal to the injury (which in most cases is farther from the neuron's cell body) degenerates. A related process of dying back or retrograde degeneration known as 'Wallerian-like degeneration' occurs in many neurodegenerative diseases, especially those where axonal transport is impaired such as amyotrophic lateral sclerosis (ALS) and Alzheimer's disease. Primary culture studies suggest that a failure to deliver sufficient quantities of the essential axonal protein NMNAT2 is a key initiating event.

Wallerian degeneration occurs after axonal injury in both the peripheral nervous system (PNS) and central nervous system (CNS). It occurs in the section of the axon distal to the site of injury and usually begins within 24–36 hours of a lesion. Prior to degeneration, the distal section of the axon tends to remain electrically excitable. After injury, the axonal skeleton disintegrates, and the axonal membrane breaks apart. Axonal degeneration is followed by degradation of the myelin sheath and infiltration by macrophages. The macrophages, accompanied by Schwann cells, serve to clear the debris from the degeneration.

Schwann cells respond to loss of axons by extrusion of their myelin sheaths, downregulation of myelin genes, dedifferentiation and proliferation. They finally align in tubes (Büngner bands) and express surface molecules that guide regenerating fibers. Within 4 days of the injury, the distal end of the portion of the nerve fiber proximal to the lesion sends out sprouts towards those tubes and these sprouts are attracted by growth factors produced by Schwann cells in the tubes. If a sprout reaches the tube, it grows into it and advances about 1 mm per day, eventually reaching and reinnervating the target tissue. If the sprouts cannot reach the tube, for instance because the gap is too wide or scar tissue has formed, surgery can help to guide the sprouts into the tubes. Regeneration is efficient in the PNS, with near complete recovery in case of lesions that occur close to the distal nerve terminal. However recovery is hardly observed at all in the spinal cord. One crucial difference is that in the CNS, including the spinal cord, myelin sheaths are produced by oligodendrocytes and not by Schwann cells.

History
Wallerian degeneration is named after Augustus Volney Waller. Waller experimented on frogs in 1850, by severing their glossopharyngeal and hypoglossal nerves. He then observed the distal nerves from the site of injury, which were separated from their cell bodies in the brain stem. Waller described the disintegration of myelin, which he referred to as "medulla", into separate particles of various sizes. The degenerating axons formed droplets that could be stained, thus allowing for studies of the course of individual nerve fibres.

Axonal degeneration
Although most injury responses include a calcium influx signaling to promote resealing of severed parts, axonal injuries initially lead to acute axonal degeneration (AAD), which is rapid separation of the proximal (the part nearer the cell body) and distal ends within 30 minutes of injury. After separation, dystrophic bulb structures form at both terminals and the transected membranes are sealed. A brief latency phase occurs in the distal segment during which it remains electrically excitable and structurally intact. Degeneration follows with swelling of the axolemma, and eventually the formation of bead-like axonal spheroids. The process takes roughly 24 hours in the PNS, and longer in the CNS. The signaling pathways leading to axolemma degeneration are currently poorly understood. However, research has shown that this AAD process is calcium–independent.

Granular disintegration of the axonal cytoskeleton and inner organelles occurs after axolemma degradation. Early changes include accumulation of mitochondria in the paranodal regions at the site of injury. Endoplasmic reticulum degrades and mitochondria swell up and eventually disintegrate. The depolymerization of microtubules occurs and is soon followed by degradation of the neurofilaments and other cytoskeleton components. The disintegration is dependent on ubiquitin and calpain proteases (caused by influx of calcium ion), suggesting that axonal degeneration is an active process and not a passive one as previously misunderstood. Thus the axon undergoes complete fragmentation. The rate of degradation is dependent on the type of injury and is also slower in the CNS than in the PNS. Another factor that affects degradation rate is the diameter of the axon: larger axons require a longer time for the cytoskeleton to degrade and thus take a longer time to degenerate.

Myelin clearance
Myelin is a phospholipid membrane that wraps around axons to provide them with insulation. It is produced by Schwann cells in the PNS, and by oligodendrocytes in the CNS. Myelin clearance is the next step in Wallerian degeneration following axonal degeneration. The cleaning up of myelin debris is different for PNS and CNS. PNS is much faster and efficient at clearing myelin debris in comparison to CNS, and Schwann cells are the primary cause of this difference. Another key aspect is the change in permeability of the blood-tissue barrier in the two systems. In PNS, the permeability increases throughout the distal stump, but the barrier disruption in CNS is limited to just the site of injury.

Clearance in PNS
The response of Schwann cells to axonal injury is rapid. The time period of response is estimated to be prior to the onset of axonal degeneration. Neuregulins are believed to be responsible for the rapid activation. They activate ErbB2 receptors in the Schwann cell microvilli, which results in the activation of the mitogen-activated protein kinase (MAPK). Although MAPK activity is observed, the injury sensing mechanism of Schwann cells is yet to be fully understood. The 'sensing' is followed by decreased synthesis of myelin lipids and eventually stops within 48 hrs. The myelin sheaths separate from the axons at the Schmidt-Lanterman incisures first and then rapidly deteriorate and shorten to form bead-like structures. Schwann cells continue to clear up the myelin debris by degrading their own myelin, phagocytose extracellular myelin and attract macrophages to myelin debris for further phagocytosis. However, the macrophages are not attracted to the region for the first few days; hence the Schwann cells take the major role in myelin cleaning until then.

Schwann cells have been observed to recruit macrophages by release of cytokines and chemokines after sensing of axonal injury. The recruitment of macrophages helps improve the clearing rate of myelin debris. The resident macrophages present in the nerves release further chemokines and cytokines to attract further macrophages. The degenerating nerve also produce macrophage chemotactic molecules. Another source of macrophage recruitment factors is serum. Delayed macrophage recruitment was observed in B-cell deficient mice lacking serum antibodies. These signaling molecules together cause an influx of macrophages, which peaks during the third week after injury. While Schwann cells mediate the initial stage of myelin debris clean up, macrophages come in to finish the job. Macrophages are facilitated by opsonins, which label debris for removal. The 3 major groups found in serum include complement, pentraxins, and antibodies. However, only complement has shown to help in myelin debris phagocytosis.

Murinson et al. (2005) observed that non-myelinated or myelinated Schwann cells in contact with an injured axon enter cell cycle thus leading to proliferation. Observed time duration for Schwann cell divisions were approximately 3 days after injury. Possible sources of proliferation signal are attributed to the ErbB2 receptors and the ErbB3 receptors. This proliferation could further enhance the myelin cleaning rates and plays an essential role in regeneration of axons observed in PNS. Schwann cells emit growth factors that attract new axonal sprouts growing from the proximal stump after complete degeneration of the injured distal stump. This leads to possible reinnervation of the target cell or organ. However, the reinnervation is not necessarily perfect, as possible misleading occurs during reinnervation of the proximal axons to target cells.

Clearance in CNS
In comparison to Schwann cells, oligodendrocytes require axon signals to survive. In their developmental stages, oligodendrocytes that fail to make contact to axon and receive axon signals undergo apoptosis.

Experiments in Wallerian degeneration have shown that upon injury oligodendrocytes either undergo programmed cell death or enter a state of rest. Therefore, unlike Schwann cells, oligodendrocytes fail to clean up the myelin sheaths and their debris. In experiments conducted on rats, myelin sheaths were found for up to 22 months. Therefore, CNS rates of myelin sheath clearance are very slow and could possibly be the cause for hindrance in the regeneration capabilities of the CNS axons as no growth factors are available to attract the proximal axons. Another feature that results eventually is glial scar formation. This further hinders chances for regeneration and reinnervation.

Oligodendrocytes fail to recruit macrophages for debris removal. Macrophage entry in general into CNS site of injury is very slow. In contrast to PNS, microglia play a vital role in CNS Wallerian degeneration. However, their recruitment is slower in comparison to macrophage recruitment in PNS by approximately 3 days. Further, microglia might be activated but hypertrophy, and fail to transform into fully phagocytic cells. Those microglia that do transform, clear out the debris effectively. Differentiating phagocytic microglia can be accomplished by testing for expression of major histocompatibility complex (MHC) class I and II during Wallerian degeneration. The rate of clearance is very slow among microglia in comparison to macrophages. Possible source for variations in clearance rates could include lack of opsonin activity around microglia, and the lack of increased permeability in the blood–brain barrier. The decreased permeability could further hinder macrophage infiltration to the site of injury.

These findings have suggested that the delay in Wallerian degeneration in CNS in comparison to PNS is caused not due to a delay in axonal degeneration, but rather is due to the difference in clearance rates of myelin in CNS and PNS.

Regeneration
Regeneration follows degeneration. Regeneration is rapid in PNS, allowing for rates of up to 1 millimeter a day of regrowth. Grafts may also be needed to allow for appropriate reinnervation. It is supported by Schwann cells through growth factors release. CNS regeneration is much slower, and is almost absent in most vertebrate species. The primary cause for this could be the delay in clearing up myelin debris. Myelin debris, present in CNS or PNS, contains several inhibitory factors. The prolonged presence of myelin debris in CNS could possibly hinder the regeneration. An experiment conducted on newts, animals that have fast CNS axon regeneration capabilities, found that Wallerian degeneration of an optic nerve injury took up to 10 to 14 days on average, further suggesting that slow clearance inhibits regeneration.

Schwann cells and endoneural fibroblasts in PNS
In healthy nerves, nerve growth factor (NGF) is produced in very small amounts. However, upon injury, NGF mRNA expression increases by five to seven-fold within a period of 14 days. Nerve fibroblasts and Schwann cells play an important role in increased expression of NGF mRNA. Macrophages also stimulate Schwann cells and fibroblasts to produce NGF via macrophage-derived interleukin-1. Other neurotrophic molecules produced by Schwann cells and fibroblasts together include brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, ciliary neurotrophic factor, leukemia inhibitory factor, insulin-like growth factor, and fibroblast growth factor. These factors together create a favorable environment for axonal growth and regeneration. Apart from growth factors, Schwann cells also provide structural guidance to further enhance regeneration. During their proliferation phase, Schwann cells begin to form a line of cells called Bands of Bungner within the basal laminar tube. Axons have been observed to regenerate in close association to these cells. Schwann cells upregulate the production of cell surface adhesion molecule ninjurin further promoting growth. These lines of cell guide the axon regeneration in proper direction. The possible source of error that could result from this is possible mismatching of the target cells as discussed earlier.

Due to lack of such favorable promoting factors in CNS, regeneration is stunted in CNS.

Wallerian degeneration slow
Mice belonging to the strain C57BL/Wlds have delayed Wallerian degeneration, and, thus, allow for the study of the roles of various cell types and the underlying cellular and molecular processes. Current understanding of the process has been possible via experimentation on the Wlds strain of mice. The mutation occurred first in mice in Harlan-Olac, a laboratory producing animals the United Kingdom. The Wlds mutation is an autosomal-dominant mutation occurring in the mouse chromosome 4. The gene mutation is an 85-kb tandem triplication, occurring naturally. The mutated region contains two associated genes: nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1) and ubiquitination factor e4b (UBE4B). A linker region encoding 18 amino acids is also part of the mutation. The protective effect of the WldS protein has been shown to be due to the NMNAT1 region's NAD+ synthesizing active site.

Although the protein created localizes within the nucleus and is barely detectable in axons, studies suggest that its protective effect is due to its presence in axonal and terminal compartments. The protection provided by the WldS protein is intrinsic to the neurons and not surrounding support cells, and is only locally protective of the axon, indicating an intracellular pathway is responsible for mediating Wallerian degeneration.

Effects of the WldS mutation
The mutation causes no harm to the mouse. The only known effect is that the Wallerian degeneration is delayed by up to three weeks on average after injury of a nerve. At first, it was suspected that the Wlds mutation slows down the macrophage infiltration, but recent studies suggest that the mutation protects axons rather than slowing down the macrophages. The process by which the axonal protection is achieved is poorly understood. However, studies suggest that the Wlds mutation leads to increased NMNAT1 activity, which leads to increased NAD+ synthesis. This in turn activates SIRT1-dependent process within the nucleus, causing changes in gene transcription. NAD+ by itself may provide added axonal protection by increasing the axon's energy resources. More recent work, however, raises doubt that either NMNAT1 or NAD+ can substitute for the full length Wlds gene. These authors demonstrated by both in vitro and in vivo methods that the protective effect of overexpression of NMNAT1 or the addition of NAD+ did not protect axons from degeneration. However, later studies showed that NMNAT1 is protective when combined with an axonal targeting peptide, suggesting that the key to the protection provided by WldS was the combination of NMNAT1's activity and the axonal localization provided by the N-terminal domain of the chimeric protein.

The provided axonal protection delays the onset of Wallerian degeneration. Schwann cell activation should therefore be delayed, as they would not detect axonal degradation signals from ErbB2 receptors. In experiments on Wlds mutated mice, macrophage infiltration was considerably delayed by up to six to eight days. However, once the axonal degradation has begun, degeneration takes its normal course, and, respective of the nervous system, degradation follows at the above-described rates. Possible effects of this late onset are weaker regenerative abilities in the mice. Studies indicate that regeneration may be impaired in WldS mice, but this is likely a result of the environment being unfavorable for regeneration due to the continued existence of the undegenerated distal fiber, whereas normally debris is cleared, making way for new growth.

SARM1
The Wallerian degeneration pathway has been further illuminated by the discovery that sterile alpha and TIR motif containing 1 (SARM1) protein plays a central role in the Wallerian degeneration pathway. The gene was first identified in a Drosophila melanogaster mutagenesis screen, and subsequently knockouts of its homologue in mice showed robust protection of transected axons comparable to that of WldS.

SARM1 catalyzes the synthesis and hydrolysis of cyclic ADP-ribose (cADPR) from NAD+ to ADP-ribose. SARM1 activation locally triggers a rapid collapse of NAD+ levels in the distal section of the injured axon, which then undergoes degeneration. This collapse in NAD+ levels was later shown to be due to SARM1's TIR domain having intrinsic NAD+ cleavage activity. The SARM1 protein has four domains, a mitochondrial localization signal, an auto-inhibitory N-terminus region consisting of armadillo/HEAT motifs, two sterile alpha motifs responsible for multimerization, and a C-terminus Toll/Interleukin-1 receptor that possesses enzymatic activity. Activation of SARM1 is sufficient to collapse NAD+ levels and initiate the Wallerian degeneration pathway.

The activity of SARM1 helps to explain the protective nature of the survival factor NMNAT2, as NMNAT enzymes have been shown to prevent SARM1-mediated depletion of NAD+. This relationship is further supported by the fact that mice lacking NMNAT2, which are normally not viable, are completely rescued by SARM1 deletion, placing NMNAT2 activity upstream of SARM1. Other pro-degeneration signaling pathways, such as the MAP kinase pathway, have been linked to SARM1 activation. MAPK signaling has been shown to promote the loss of NMNAT2, thereby promoting SARM1 activation, although SARM1 activation also triggers the MAP kinase cascade, indicating some form of feedback loop exists. One explanation for the protective effect of the WldS mutation is that the NMNAT1 region, which is normally localized to the soma, substitutes for the labile survival factor NMNAT2 to prevent SARM1 activation when the N-terminal Ube4 region of the WldS protein localizes it to the axon. The fact that the enhanced survival of WldS axons is due to the slower turnover of WldS compared to NMNAT2 also helps explain why SARM1 knockout confers longer protection, as SARM1 will be completely inactive regardless of inhibitor activity whereas WldS will eventually be degraded. Possibles implications of the SARM1 pathway in regard to human health may be found in animal models which exhibit traumatic brain injury, as mice which contain Sarm1 deletions in addition to WldS show decreased axonal damage following injury. Specific mutations in NMNAT2 have linked the Wallerian degeneration mechanism to two neurological diseases.

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

title: Wallerian degeneration


text:
Vassy, Calvados

Vassy is a former commune in the Calvados department in the Normandy region in northwestern France. On 1 January 2016, it was merged into the new commune of Valdallière.

It is said to be the origin of the surnames de Vesci and Vesely in England, introduced after the Norman Conquest in 1066.

title: Vassy, Calvados


text:
Talk:Loveland frog

Possible explanation
One of the possible explanations in the article mentions the possiblity of this cryptid being a mis-identified alligator but notes extreme suspicion of alligators being in Ohio. I live in Cincinnati, Ohio which is just west of Loveland and want to remind readers that Loveland (and Cincinnati) are located on the SOUTHERN border of Ohio which is the Ohio River. The Ohio River goes down to the Missisippi River- where there are plenty of alligators (even indigeonous as close as Memphis, TN)- so it is not impossible for an occasional alligator to wander on up the Ohio River every so often; there have been several gaters that I know of being captured within my lifetime in the waters of the Ohio River and it contributary rivers/stream/creeks/oxbows - just Google "Cincinnati" and "Alligator" and you'll see what I'm talking about. Also, Cincinnati, unlike the majority of Ohio, is within the Humid-Subtropical climate and it is possible for a gator to survive winters here should it find a suitable micro-climate in a nice remote stretch of riverbank. Ohio, particularly the Cincinnati area, is not located in the Tundra. :-). P.S. there are about three or four types of lizards that live here in Cincinnati so it can't be that inhospitable. Regardless, thanks for the really cool and fun article. Later Gater, Paul

Innsmouth?
Shadow over Innsmouth anyone? I know that there's not much of a point in mentioning theories but this certainly reminds one a little —The preceding unsigned comment was added by 204.116.39.63 (talk • contribs).

... Thats exactly what I was just thinking. The ancients walk among us apparently. I'm buying a shotgun haha —The preceding unsigned comment was added by 69.19.153.134 (talk • contribs).

This article clearly is the same as the Loveland Lizard and needs to be merged. Cameron 16:21, 17 February 2006 (UTC)

 * The "Loveland Lizard" entry was deleted due to copyright violation. However, we should probably still bring in the data mentioned in the original About.com article "The Top 10 Most Mysterious Creatures of Modern Times" (see entry #8) that it was copied from. 151.197.51.123 22:50, 21 May 2006 (UTC)

Merge These two articles clearly describe the same (largely discredited) cryptid; no need exists for two separate articles. KevinOKeeffe 06:07, 1 September 2006 (UTC)

Merge Clearly two separate articles on the same (dubious) thing. Nareek 04:29, 27 September 2006 (UTC)

Fair use rationale for Image:Lovelandfrog.jpg
Image:Lovelandfrog.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in this Wikipedia article constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.

Please go to the image description page and edit it to include a fair use rationale. Using one of the templates at Fair use rationale guideline is an easy way to insure that your image is in compliance with Wikipedia policy, but remember that you must complete the template. Do not simply insert a blank template on an image page.

If there is other fair use media, consider checking that you have specified the fair use rationale on the other images used on this page. Note that any fair use images lacking such an explanation can be deleted one week after being tagged, as described on criteria for speedy deletion. If you have any questions please ask them at the Media copyright questions page. Thank you.

BetacommandBot (talk) 19:18, 2 January 2008 (UTC)

'Multiple issues'
I noticed that this article really only contains 3 lines as of this message. I've added a reference to the opening line, and now every assertion made in the article seems to be covered. 7 years later, and I think it's now possible to retire the needs additional citations tag. As for notability, I am surprised the question was ever raised, significant sources exist out there for this and are easy to find. Ryan shell (talk) 23:18, 27 December 2014 (UTC)

Expansion
This article is way too short and needs o be expanded. The article is is only composed of a long lead section and should be split off into separate sections and should include: Eyewitness' description of the creature, a history of sightings, theories (if any), and appearances/references in popular culture. The image used in the article is awful and should be replaced with an eyewitness sketch of the creature. All of these changes and additions need to occur in order for this article to meet Wikipiedia's guidelines and standards of a well developed and properly sourced article.--Paleface Jack (talk) 16:14, 1 April 2016 (UTC)
 * Please suggest specific independent reliable sources for your suggested expansion. - LuckyLouie (talk) 17:02, 1 April 2016 (UTC)
 * I've added some higher quality WP:FRIND sources so as to be less reliant on the Skeptoid source. - LuckyLouie (talk) 20:06, 20 November 2017 (UTC)

And now someone has tagged the article as "incomplete" again. Care to use the Talk page to be more specific? - LuckyLouie (talk) 20:52, 9 April 2018 (UTC)

I did. It's just one big history section and should also include Description, theories (from professional sources), and popular culture sections as well. Secondly, why was the infobox removed? I've been seeing a lot of cryptid articles with their infobox removed and I don't understand it.--Paleface Jack 21:18, 9 April 2018 (UTC)
 * These infoboxes are being removed because they're usually redundant, contain misinformation, or are otherwise inappropriate. Infoboxes are handy for articles about, say, vehicle models, but less so when there's any level of complexity involves, such as in the case of folklore-related topics. Cryptozoology-related articles are currently under heavy scrutiny on the platform. :bloodofox: (talk) 21:24, 9 April 2018 (UTC)
 * How about a compromise? No superfluous infobox, but we use section headers, per WP:SUMMARY summary style, and a summary of the article per WP:LEAD (that includes pop culture). - LuckyLouie (talk) 03:08, 10 April 2018 (UTC)

I've been seeing a lot of Cryptid articles have the lead section changes so that in stead of the appropriate "cryptid" it's been changed to "Legendary creature" which is a bit misguided. Loveland Frog for example has this issue. It should say "Humanoid cryptid". I've also been thinking that the "Legendary Creature" Infobox could be reworked so that it doesn't contain redundant info and more of the basics on cryptids since it seems to be more mythological based rather than cryptid/biological based.--Paleface Jack 23:09, 10 April 2018 (UTC)

Inaccurate information regarding the Loveland Frog
I have attempted to edit the Loveland Frog wiki page twice due to inaccurate information. Both times it was changed back by LuckyLouie. I have cited the wiki cryptidz page "http://cryptidz.wikia.com/wiki/Loveland_Frogmen" which has the exact story which was verified for the last 40 years. Due to a recent article in 2016 which has Officer Mark Matthews recant his previous and originals statements this wiki page for the Loveland Frog has this new article listed as the "actual events". I feel the author of this page should take in consideration verified facts from witnesses in this story instead of a recant of events from Officer Mark Matthews. It appears Matthews would just like to wash his hands with this story due to public pressure. — Preceding unsigned comment added by 74.83.185.145 (talk) 20:12, 21 February 2018 (UTC)
 * A lot of new users make this mistake, so don't feel too badly. Wikipedia is an encyclopedia, not an open platform or a place to right perceived wrongs. The encyclopedia's policies require that editors cite reliable sources for article content. A crytozoology wiki is not a reliable source as defined by our policies WP:RS, WP:FRINGE and WP:USERGEN. There is no single "author" for Wikipedia articles, it is a volunteer effort by many contributors who agree to abide by community-endorsed policy guidelines. - LuckyLouie (talk) 21:45, 21 February 2018 (UTC)

Image
, please explain your rationale for deleting this image: It's on the corresponding page for all the other language versions, so why isn't it good enough for this? Re: your edit summary, I didn't add it because it's "funny", I added it because there's no reason to not have an image if one is available on Commons. And what do you mean Triangulum is an "unknown artist"? They've done plenty of artwork that's on many other pages, why not this one? --Qualiesin (talk) 03:51, 28 April 2020 (UTC)
 * Loveland frog.png seems to have been generated for some cryptozoology catalog, e.g. it includes a scale drawing of the creature compared to a human. What measurement this is based on I can't imagine. We'd do better to find an illustration that is more explicitly an artist's impression of the legend. - LuckyLouie (talk) 17:47, 7 May 2020 (UTC)

Sources cited in the article describe it as roughly 4 ft tall, what's wrong with having a scale? This is an artist's impression. --Qualiesin (talk) 23:35, 7 May 2020 (UTC)
 * The image is one in a cryptozoology series by an artist who imagines wikipedia is a field guide for monster-spotting ; ) In any case, I've cropped the cheesy human/monster scale. It may be enough to mask the stink of pseudoscience. - LuckyLouie (talk) 02:07, 8 May 2020 (UTC)

I've reverted the edit, since cropping it seems to be enough for your ridiculously stringent standards. --Qualiesin (talk) 15:39, 8 May 2020 (UTC)
 * This image emphasizes the fringe aspects of this article. Ask yourself: Why would we choose to include an image of a giant, humanoid frog rahter than an iguana? We're not here to sensationalize the material within the article, especially in any way that can be seen to be WP:PROFRINGE. Wikipedia is not a compendium of pseudoscience and sensationalism. Come on. :bloodofox: (talk) 06:39, 12 May 2020 (UTC)

I saw it
It’s real It is in my house 2601:4A:401:B0E0:40B3:7BA9:8D4A:9453 (talk) 22:59, 28 December 2021 (UTC)
 * Uh-huh. Sure. Dronebogus (talk) 23:09, 28 December 2021 (UTC)

The story of the Loveland frog
Put a police name is Sharkey sought a creature on the road in their police truck and it was a human frog or a humanoid frog it was walking the police station was a rose a frog human and another police man shot the creature with a gun and it showed that it was in a Guana but it wasn't in a Guana it was a lovely frog man sometimes called the Loveland lizard 2601:603:4C81:AA40:3036:4AE7:4289:CF82 (talk) 01:14, 3 January 2023 (UTC)

Frog
So a animal that stands up to 4 feet  The police Shockey and Matt saw a frog  shot  The creature and he showed the dead animal it was a iguana but it wasn't iguana it lost tail it's a frog man or the lizard man 2601:603:4C81:AA40:CAF:55D3:3C55:A915 (talk) 02:38, 4 January 2023 (UTC)

Moeller Prank?
Regarding the supposed revelation that a Moeller student was responsible for the 2016 prank: I read the citation, and it's a humorous school newspaper article about a student dressed as a frog. It mentioned the 2016 incident, but it doesn't claim that a Moeller student was responsible.

In reviewing this article's history, it looks like the claim was originally inserted in the article by an anonymous editor on October 27, 2020. User:Trevor Sinclair asked for a citation on December 25, 2020, and User:Ixfd64 made a good faith effort to provide one on June 15, 2021, with the revision comment, "not sure if school newspapers are considered reliable sources, but this is the best I could find."

Unfortunately, the citation doesn't back up the claim. I did an extensive search to find an alternative source, to no avail, so I'm going to remove the claim. —16:02, 19 January 2023 (UTC) Eekim (talk) 16:02, 19 January 2023 (UTC)

Song link
Why is a random song about the frogman significant? There's a bunch of other songs about the frogman on Spotify (which it cites) that have more plays than it, so what's so significant about this one? 86.21.208.77 (talk) 03:16, 21 March 2023 (UTC)

The movie, "Frogman."
I'm kind of a found footage horror movie nerd, and am currently watching one called "Frogman." I looked up said frogman to see if it was a real thing or just made up for the movie (they stop by signs featuring the frogman, leading me to think it was real) and noticed that the Loveland Frog entry was missing any mention of the movie. So I added it. It's my first real addition to Wikipedia, I think. So if I screwed up in formatting or something and someone knows how to fix it, feel free. Andrewjustinhollins (talk) 21:15, 22 March 2024 (UTC)

title: Talk:Loveland frog


text:
Wikipedia:Articles for deletion/Trey Menefee

Trey Menefee
Vanity page. --jpgordon 22:20, 3 Oct 2004 (UTC)
 * Vanity biography of a non-notable person. Delete. --Slowking Man 23:40, Oct 3, 2004 (UTC)
 * Delete. Concur with above. jni 06:57, 4 Oct 2004 (UTC)
 * Delete. Vanity. Best known for bringing booze to a voter registration drive?   — Gwalla | Talk 18:10, 4 Oct 2004 (UTC)
 * keep. Notable.  Not vanity. anthony (see warning) 22:07, 6 Oct 2004 (UTC)
 * Delete. Vain nonnotability. —tregoweth 17:36, Oct 7, 2004 (UTC)
 * Delete: Non-notable. Geogre 14:19, 8 Oct 2004 (UTC)


text:
DFE

DFE or DfE may refer to:

Organizations

 * Department for the Economy, Northern Ireland
 * Department for Education, UK
 * DePatie–Freleng Enterprises, a defunct animation company

Science

 * Dilated fundus examination of the eye
 * Distribution of fitness effects
 * Dietary folate equivalent, bioavailability of folate

Technology

 * Design-focused evaluation of educational quality
 * Design for the Environment of a product or service
 * DFE Ascender, an ultralight aircraft

Other

 * Dragon Fli Empire, a Canadian hip hop group
 * Dunfermline Town railway station, Scotland, National Rail station code

title: DFE


text:
Disjoint-set data structure

In computer science, a disjoint-set data structure, also called a union–find data structure or merge–find set, is a data structure that stores a collection of disjoint (non-overlapping) sets. Equivalently, it stores a partition of a set into disjoint subsets. It provides operations for adding new sets, merging sets (replacing them by their union), and finding a representative member of a set. The last operation makes it possible to find out efficiently if any two elements are in the same or different sets.

While there are several ways of implementing disjoint-set data structures, in practice they are often identified with a particular implementation called a disjoint-set forest. This is a specialized type of forest which performs unions and finds in near-constant amortized time. To perform a sequence of $m$ addition, union, or find operations on a disjoint-set forest with $n$ nodes requires total time $O(n)$, where $O(n)$ is the extremely slow-growing inverse Ackermann function. Disjoint-set forests do not guarantee this performance on a per-operation basis. Individual union and find operations can take longer than a constant times $O(α(n))$ time, but each operation causes the disjoint-set forest to adjust itself so that successive operations are faster. Disjoint-set forests are both asymptotically optimal and practically efficient.

Disjoint-set data structures play a key role in Kruskal's algorithm for finding the minimum spanning tree of a graph. The importance of minimum spanning trees means that disjoint-set data structures underlie a wide variety of algorithms. In addition, disjoint-set data structures also have applications to symbolic computation, as well as in compilers, especially for register allocation problems.

History
Disjoint-set forests were first described by Bernard A. Galler and Michael J. Fischer in 1964. In 1973, their time complexity was bounded to $$O(\log^{*}(n))$$, the iterated logarithm of $$n$$, by Hopcroft and Ullman. In 1975, Robert Tarjan was the first to prove the $$O(m\alpha(n))$$ (inverse Ackermann function) upper bound on the algorithm's time complexity,. He also proved it to be tight. In 1979, he showed that this was the lower bound for a certain class of algorithms, that include the Galler-Fischer structure. In 1989, Fredman and Saks showed that $$\Omega(\alpha(n))$$ (amortized) words of $$O(\log n)$$ bits must be accessed by any disjoint-set data structure per operation, thereby proving the optimality of the data structure in this model.

In 1991, Galil and Italiano published a survey of data structures for disjoint-sets.

In 1994, Richard J. Anderson and Heather Woll described a parallelized version of Union–Find that never needs to block.

In 2007, Sylvain Conchon and Jean-Christophe Filliâtre developed a semi-persistent version of the disjoint-set forest data structure and formalized its correctness using the proof assistant Coq. "Semi-persistent" means that previous versions of the structure are efficiently retained, but accessing previous versions of the data structure invalidates later ones. Their fastest implementation achieves performance almost as efficient as the non-persistent algorithm. They do not perform a complexity analysis.

Variants of disjoint-set data structures with better performance on a restricted class of problems have also been considered. Gabow and Tarjan showed that if the possible unions are restricted in certain ways, then a truly linear time algorithm is possible.

Representation
Each node in a disjoint-set forest consists of a pointer and some auxiliary information, either a size or a rank (but not both). The pointers are used to make parent pointer trees, where each node that is not the root of a tree points to its parent. To distinguish root nodes from others, their parent pointers have invalid values, such as a circular reference to the node or a sentinel value. Each tree represents a set stored in the forest, with the members of the set being the nodes in the tree. Root nodes provide set representatives: Two nodes are in the same set if and only if the roots of the trees containing the nodes are equal.

Nodes in the forest can be stored in any way convenient to the application, but a common technique is to store them in an array. In this case, parents can be indicated by their array index. Every array entry requires $O(α(n))$ bits of storage for the parent pointer. A comparable or lesser amount of storage is required for the rest of the entry, so the number of bits required to store the forest is $O(1)$. If an implementation uses fixed size nodes (thereby limiting the maximum size of the forest that can be stored), then the necessary storage is linear in $n$.

Operations
Disjoint-set data structures support three operations: Making a new set containing a new element; Finding the representative of the set containing a given element; and Merging two sets.

Making new sets
The  operation adds a new element into a new set containing only the new element, and the new set is added to the data structure. If the data structure is instead viewed as a partition of a set, then the  operation enlarges the set by adding the new element, and it extends the existing partition by putting the new element into a new subset containing only the new element.

In a disjoint-set forest,  initializes the node's parent pointer and the node's size or rank. If a root is represented by a node that points to itself, then adding an element can be described using the following pseudocode:

function MakeSet(x) is if x is not already in the forest then x.parent := x x.size := 1    // if nodes store size x.rank := 0    // if nodes store rank end if end function

This operation has constant time complexity. In particular, initializing a disjoint-set forest with $n$ nodes requires $O(1)$ time.

Lack of a parent assigned to the node implies that the node is not present in the forest.

In practice,  must be preceded by an operation that allocates memory to hold $O(mα(n))$. As long as memory allocation is an amortized constant-time operation, as it is for a good dynamic array implementation, it does not change the asymptotic performance of the random-set forest.

Finding set representatives
The  operation follows the chain of parent pointers from a specified query node $x$ until it reaches a root element. This root element represents the set to which $x$ belongs and may be $x$ itself. returns the root element it reaches.

Performing a  operation presents an important opportunity for improving the forest. The time in a  operation is spent chasing parent pointers, so a flatter tree leads to faster   operations. When a  is executed, there is no faster way to reach the root than by following each parent pointer in succession. However, the parent pointers visited during this search can be updated to point closer to the root. Because every element visited on the way to a root is part of the same set, this does not change the sets stored in the forest. But it makes future  operations faster, not only for the nodes between the query node and the root, but also for their descendants. This updating is an important part of the disjoint-set forest's amortized performance guarantee.

There are several algorithms for  that achieve the asymptotically optimal time complexity. One family of algorithms, known as path compression, makes every node between the query node and the root point to the root. Path compression can be implemented using a simple recursion as follows:

function Find(x) is if x.parent ≠ x then x.parent := Find(x.parent) return x.parent else return x end if end function

This implementation makes two passes, one up the tree and one back down. It requires enough scratch memory to store the path from the query node to the root (in the above pseudocode, the path is implicitly represented using the call stack). This can be decreased to a constant amount of memory by performing both passes in the same direction. The constant memory implementation walks from the query node to the root twice, once to find the root and once to update pointers:

function Find(x) is root := x while root.parent ≠ root do root := root.parent end while while x.parent ≠ root do parent := x.parent x.parent := root x := parent end while return root end function

Tarjan and Van Leeuwen also developed one-pass  algorithms that retain the same worst-case complexity but are more efficient in practice. These are called path splitting and path halving. Both of these update the parent pointers of nodes on the path between the query node and the root. Path splitting replaces every parent pointer on that path by a pointer to the node's grandparent:

function Find(x) is while x.parent ≠ x do (x, x.parent) := (x.parent, x.parent.parent) end while return x end function

Path halving works similarly but replaces only every other parent pointer:

function Find(x) is while x.parent ≠ x do x.parent := x.parent.parent x := x.parent end while return x end function

Merging two sets

The operation  replaces the set containing $x$ and the set containing $y$ with their union. first uses  to determine the roots of the trees containing $x$ and $y$. If the roots are the same, there is nothing more to do. Otherwise, the two trees must be merged. This is done by either setting the parent pointer of $x$'s root to $y$'s, or setting the parent pointer of $y$'s root to $x$'s.

The choice of which node becomes the parent has consequences for the complexity of future operations on the tree. If it is done carelessly, trees can become excessively tall. For example, suppose that  always made the tree containing $x$ a subtree of the tree containing $y$. Begin with a forest that has just been initialized with elements $$1, 2, 3, \ldots, n,$$ and execute,  , ...,. The resulting forest contains a single tree whose root is $n$, and the path from 1 to $n$ passes through every node in the tree. For this forest, the time to run  is $α(n)$.

In an efficient implementation, tree height is controlled using union by size or union by rank. Both of these require a node to store information besides just its parent pointer. This information is used to decide which root becomes the new parent. Both strategies ensure that trees do not become too deep.

Union by size
In the case of union by size, a node stores its size, which is simply its number of descendants (including the node itself). When the trees with roots $x$ and $y$ are merged, the node with more descendants becomes the parent. If the two nodes have the same number of descendants, then either one can become the parent. In both cases, the size of the new parent node is set to its new total number of descendants.

function Union(x, y) is // Replace nodes by roots x := Find(x) y := Find(y) if x = y then return // x and y are already in the same set end if // If necessary, swap variables to ensure that // x has at least as many descendants as y if x.size < y.size then (x, y) := (y, x) end if // Make x the new root y.parent := x // Update the size of x x.size := x.size + y.size end function

The number of bits necessary to store the size is clearly the number of bits necessary to store $n$. This adds a constant factor to the forest's required storage.

Union by rank
For union by rank, a node stores its, which is an upper bound for its height. When a node is initialized, its rank is set to zero. To merge trees with roots $x$ and $y$, first compare their ranks. If the ranks are different, then the larger rank tree becomes the parent, and the ranks of $x$ and $y$ do not change. If the ranks are the same, then either one can become the parent, but the new parent's rank is incremented by one. While the rank of a node is clearly related to its height, storing ranks is more efficient than storing heights. The height of a node can change during a  operation, so storing ranks avoids the extra effort of keeping the height correct. In pseudocode, union by rank is:

function Union(x, y) is // Replace nodes by roots x := Find(x) y := Find(y) if x = y then return // x and y are already in the same set end if // If necessary, rename variables to ensure that // x has rank at least as large as that of y if x.rank < y.rank then (x, y) := (y, x) end if // Make x the new root y.parent := x // If necessary, increment the rank of x if x.rank = y.rank then x.rank := x.rank + 1 end if end function

It can be shown that every node has rank $$\lfloor \log n \rfloor$$ or less. Consequently each rank can be stored in $α(n)$ bits and all the ranks can be stored in $Θ(log n)$ bits. This makes the ranks an asymptotically negligible portion of the forest's size.

It is clear from the above implementations that the size and rank of a node do not matter unless a node is the root of a tree. Once a node becomes a child, its size and rank are never accessed again.

Time complexity
A disjoint-set forest implementation in which  does not update parent pointers, and in which   does not attempt to control tree heights, can have trees with height $Θ(n log n)$. In such a situation, the  and   operations require $O(n)$ time.

If an implementation uses path compression alone, then a sequence of $n$  operations, followed by up to $x$   operations and $Union(1, 2)$   operations, has a worst-case running time of $$\Theta(n+f \cdot \left(1 + \log_{2+f/n} n\right))$$.

Using union by rank, but without updating parent pointers during, gives a running time of $$\Theta(m \log n)$$ for $m$ operations of any type, up to $n$ of which are   operations.

The combination of path compression, splitting, or halving, with union by size or by rank, reduces the running time for $m$ operations of any type, up to $n$ of which are  operations, to $$\Theta(m\alpha(n))$$. This makes the amortized running time of each operation $$\Theta(\alpha(n))$$. This is asymptotically optimal, meaning that every disjoint set data structure must use $$\Omega(\alpha(n))$$ amortized time per operation. Here, the function $$\alpha(n)$$ is the inverse Ackermann function. The inverse Ackermann function grows extraordinarily slowly, so this factor is $Union(2, 3)$ or less for any $n$ that can actually be written in the physical universe. This makes disjoint-set operations practically amortized constant time.

Proof of O(m log* n) time complexity of Union-Find
The precise analysis of the performance of a disjoint-set forest is somewhat intricate. However, there is a much simpler analysis that proves that the amortized time for any $m$  or   operations on a disjoint-set forest containing $n$ objects is $Union(n - 1, n)$, where $O(n)$ denotes the iterated logarithm.

Lemma 1: As the find function follows the path along to the root, the rank of node it encounters is increasing.

$$

Lemma 2: A node $u$ which is root of a subtree with rank $r$ has at least $$2^r$$ nodes.

$$

Lemma 3: The maximum number of nodes of rank $r$ is at most $$\frac{n}{2^r}.$$

$$

For convenience, we define "bucket" here: a bucket is a set that contains vertices with particular ranks.

We create some buckets and put vertices into the buckets according to their ranks inductively. That is, vertices with rank 0 go into the zeroth bucket, vertices with rank 1 go into the first bucket, vertices with ranks 2 and 3 go into the second bucket. If the $B$-th bucket contains vertices with ranks from interval $$\left[r, 2^r - 1\right] = [r, R - 1]$$ then the (B+1)st bucket will contain vertices with ranks from interval $$\left[R, 2^R - 1\right].$$ We can make two observations about the buckets.

 * 1) The total number of buckets is at most $O(log log n)$
 * Proof: When we go from one bucket to the next, we add one more two to the power, that is, the next bucket to $$\left[B, 2^B - 1\right]$$ will be $$\left[2^B, 2^{2^B} - 1\right]$$
 * 1) The maximum number of elements in bucket $$\left[B, 2^B - 1\right]$$ is at most $$\frac{2n}{2^B}$$
 * Proof: The maximum number of elements in bucket $$\left[B, 2^B - 1\right]$$ is at most $$\frac{n}{2^B} + \frac{n}{2^{B+1}} + \frac{n}{2^{B+2}} + \cdots + \frac{n}{2^{2^B - 1}} \leq \frac{2n}{2^B}.$$

Let $F$ represent the list of "find" operations performed, and let

$$T_1 = \sum_F\text{(link to the root)}$$ $$T_2 = \sum_F\text{(number of links traversed where the buckets are different)}$$ $$T_3 = \sum_F\text{(number of links traversed where the buckets are the same).}$$

Then the total cost of $m$ finds is $$T = T_1 + T_2 + T_3.$$

Since each find operation makes exactly one traversal that leads to a root, we have $O(n log log n)$.

Also, from the bound above on the number of buckets, we have $O(n)$.

For $T_{3}$, suppose we are traversing an edge from $u$ to $v$, where $u$ and $v$ have rank in the bucket $O(n)$ and $v$ is not the root (at the time of this traversing, otherwise the traversal would be accounted for in $T_{1}$). Fix $u$ and consider the sequence $$v_1, v_2, \ldots, v_k$$ that take the role of $v$ in different find operations. Because of path compression and not accounting for the edge to a root, this sequence contains only different nodes and because of Lemma 1 we know that the ranks of the nodes in this sequence are strictly increasing. By both of the nodes being in the bucket we can conclude that the length $k$ of the sequence (the number of times node $u$ is attached to a different root in the same bucket) is at most the number of ranks in the buckets $B$, that is, at most $$2^B - 1 - B < 2^B.$$

Therefore, $$T_3 \leq \sum_{[B, 2^B - 1]} \sum_u 2^B.$$

From Observations 1 and 2, we can conclude that $T_3 \leq \sum_{B} 2^B \frac{2n}{2^B} \leq 2 n \log^* n.$

Therefore, $$T = T_1 + T_2 + T_3 = O(m \log^*n).$$

Better worst-case time per operation
The worst-case time of the  operation in trees with Union by rank or Union by weight is $$\Theta(\log n)$$ (i.e., it is $$O(\log n)$$ and this bound is tight). In 1985, N. Blum gave an implementation of the operations that does not use path compression, but compresses trees during $$union$$. His implementation runs in $$O(\log n / \log\log n)$$ time per operation, and thus in comparison with Galler and Fischer's structure it has a better worst-case time per operation, but inferior amortized time. In 1999, Alstrup et al. gave a structure that has optimal worst-case time $$O(\log n / \log\log n)$$ together with inverse-Ackermann amortized time.

Deletion
The regular implementation as disjoint-set forests does not react favorably to the deletion of elements, in the sense that the time for  will not improve as a result of the decrease in the number of elements. However, there exist modern implementations that allow for constant-time deletion and where the time-bound for  depends on the current number of elements

Applications

Disjoint-set data structures model the partitioning of a set, for example to keep track of the connected components of an undirected graph. This model can then be used to determine whether two vertices belong to the same component, or whether adding an edge between them would result in a cycle. The Union–Find algorithm is used in high-performance implementations of unification.

This data structure is used by the Boost Graph Library to implement its Incremental Connected Components functionality. It is also a key component in implementing Kruskal's algorithm to find the minimum spanning tree of a graph.

The Hoshen-Kopelman algorithm uses a Union-Find in the algorithm.

title: Disjoint-set data structure


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Tracy Nelson (actress)

Tracy Kristine Nelson (born October 25, 1963) is an American actress. From a long line of entertainers, she is the daughter of musician Ricky Nelson and actress and painter Kristin Nelson.

Early life
Nelson was born in Santa Monica, California. She is a fourth-generation performer. Her great-grandparents were vaudeville performers Hazel Dell (née McNutt) and Roy Hilliard Snyder. Their daughter was her paternal grandmother Harriet Nelson, the star of the ABC-TV sitcom The Adventures of Ozzie and Harriet from 1952 to 1966. Her parents were musician and film actor Ricky Nelson and actress/artist Kristin Nelson (née Harmon). She has three younger siblings: Matthew Nelson and Gunnar Nelson of the 1990s rock group Nelson, and Sam Nelson. Her paternal grandparents were Ozzie and Harriet Hilliard Nelson. Nelson's maternal grandparents were football star Tom Harmon, a Heisman Trophy winner from the University of Michigan, and actress Elyse Knox. She is also the niece of actors David Nelson, and her mother's siblings Mark Harmon and Kelly Harmon.

She went to The Buckley School and graduated in 1981 from the Westlake School for Girls (now Harvard-Westlake School) in Los Angeles. She attended Bard College in upstate New York, studying Dance and European History.

Career
At age four Nelson played one of Henry Fonda and Lucille Ball's daughters in Yours, Mine and Ours (1968). Her future co-star Tom Bosley also appeared in that film.

Nelson is a professional dancer, having studied ballet for 17 years with Tania Lachine and toured throughout California in a dance company while still in grammar school. Nelson studied theater with Kim Stanley and Nina Foch and briefly in the United Kingdom, performing in The Edinburgh Fringe Festival after graduation from high school. In 1982, she played "valley girl" Jennifer DeNuccio on the television series Square Pegs, and in 1986 she landed the role of the anorexic daughter in Paul Mazursky's film Down and Out in Beverly Hills.

Nelson co-starred in the television series The Father Dowling Mysteries as "Sister Stephanie" for its three seasons. She was also a series regular on Aaron Spelling's Glitter, A League of Their Own, and the Australian television series The Man from Snowy River. Throughout the 1980s and 1990s Nelson made guest appearances on television series including Family Ties, St. Elsewhere, Murphy Brown, The Nanny, 7th Heaven, Melrose Place, Will and Grace, Matlock, Diagnosis Murder and Seinfeld. She was in the touring company and on Broadway as "Rizzo" in Grease in 1995. Nelson has appeared in several theatrical releases and over 20 television movies, including The Perfect Nanny in 2000, The Perfect Husband, Kate's Secret, The Fight for Jesse and The Rival in 2006.

She has written a book about her personal experience and a movie script about her family, The Nelsons.

Personal life
She married actor William R. Moses in 1987. They divorced in 1997 and share a daughter, actress Remington Elizabeth Moses, born in 1992. Nelson had a son, Elijah Nelson Clark, with Chris Clark in 2001.

Nelson has survived three kinds of cancer. She was diagnosed with stage 2 Hodgkin's lymphoma a month after her 1987 marriage to Moses, and one year after her father was killed in an aircraft crash on New Year's Eve 1985 in a field in DeKalb, Texas. Nelson went into remission after surgery, chemotherapy (ABVD) and radiation at Cedars-Sinai Hospital in Los Angeles.

Having suffered trauma from radiation, Nelson was diagnosed with thyroid cancer in 2005 and breast cancer in 2010. She fully recovered from a bilateral mastectomy and complete reconstruction.

Nelson is active in cancer research advocacy and was the spokesperson for The Lymphoma Research Foundation of America. She received the "Lifesaver Award" from that organization and the "Jill Ireland Award" from the Amie Karen Cancer Fund for Children.

title: Tracy Nelson (actress)


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Certified health physicist

Certified Health Physicist is an official title granted by the American Board of Health Physics, the certification board for health physicists in the United States. A Certified Health Physicist is designated by the letters CHP or DABHP (Diplomate of the American Board of Health Physics) after his or her name.

A certification by the ABHP is not a license to practice and does not confer any legal qualification to practice health physics. However, the certification is well respected and indicates a high level of achievement by those who obtain it.

Certified Health Physicists are plenary or emeritus members of the American Academy of Health Physics (AAHP). In 2019, the AAHP web site listed over 1600 plenary and emeritus members.

Professional responsibilities
A person certified as a health physicist has a responsibility to uphold the professional integrity associated with the certification to promote the practice and science of radiation safety. It is expected that such a person will always give health physics information based on the highest standards of science and professional ethics. A certified individual has a responsibility to remain professionally active in the health physics field and remain technically competent in the scientific, technical and regulatory developments in the field.

General requirements required to receive the certification
The requirements for prospective candidates for certification are
 * 1) Academics. At least a bachelor's degree from an accredited college or university in physical sciences, engineering, or in a biological science, with a minimum of 20 semester hours in physical science.
 * 2) Experience. At least six years of professional experience in health physics. By permission of the Board, advanced degrees may substitute for one year (master's degree) or two years (doctorate) of the required experience.
 * 3) References. A reference from the immediate supervisor and from at least two other individuals, including one from a currently certified Health Physicist.
 * 4) Written Report. A written report that reflects a professional health physics effort.
 * 5) Examination. A two-part exam, which is currently given during one week of the year.
 * 6) *Part I consists of 150 multiple choice questions in fundamental aspects of health physics. This portion of the test is three hours long, and can be taken without most of the above requirements. It is given at Pearson Vue testing centers throughout the world in the week before the Health Physics Society's annual meeting.
 * 7) *Part II consists of open-ended written questions, which determine competency in applied health physics. This portion of the exam is six hours long, and can only be taken after having passed Part I, or immediately after having taken Part I the week before. It is given on the Monday of the Health Physics Society's annual meeting, and on the same day at other locations throughout the country.
 * 8) *After passing Part I, the applicant must pass Part II within a period of seven years, or retake both parts.
 * 9) *If a candidate scores particularly poorly on Part II, he or she will be barred from taking it the following year.
 * 10) *Both parts include all of the topics below, but Part II requires candidates to answer only six mandatory questions and four of eight topic area questions.

Examination topics

 * Atomic structure/Radioactivity/Radioactive decay
 * Interaction of radiation with matter
 * Internal dosimetry/Internal dose calculations
 * Biological effects of ionizing radiation
 * NRC, OSHA, Regulations/Standards ICRU, ICRP, NCRP
 * Radiation Risk, BEIR III, IV, V, VI
 * External dose calculations/External dosimetry
 * Statistics
 * Instrumentation
 * Low Level Wastes, Fuel Cycle, DOT Regulations
 * Shielding and Activation
 * Air sampling/Modeling/Environmental Health Physics
 * Medical Health Physics and X-ray Protection
 * Reactor Health Physics/Criticality
 * Accelerator Health Physics
 * Lasers, UV, Microwave, RF
 * Radon

Exam reference sources
Health Physics Topics
 * Johnson, T.E. (2017). Introduction to health physics. Introduction to health physics.
 * Johnson, T.E. & Birky, B.K. (1998). Health Physics and Radiological Health.
 * Knoll, G.F. (1979). Radiation Detection and Measurement.
 * Turner, J.E. (2007). Atoms, Radiation, and Radiation Protection.

Part I
 * Bevelacqua, J.J. (1999). Basic Health Physics: Problems and Solutions.
 * ABHP Part I Question and Solutions

Part II
 * Bevelacqua, J. J. (2009). Contemporary health physics: Problems and Solutions.
 * Turner, J.E. (1988). Problems and Solutions in Radiation Protection.
 * American Board of Health Physics
 * ABHP Part II Question and Solutions

title: Certified health physicist