text:
Talk:Show jumping

Wiki Education Foundation-supported course assignment
This article was the subject of a Wiki Education Foundation-supported course assignment, between 5 April 2021 and 21 May 2021. Further details are available on the course page. Student editor(s): Izcullen13. Peer reviewers: Bffiore4, Ovxt.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 09:16, 17 January 2022 (UTC)

levels, types of competition, etc.
Could someone add a breakdown of various levels like cSIA(amateur) or CSIW, CSIP, etc.? French Wikipedia has this although not a complete list of all the types/levels. A full list would be most helpful! Oh also, can anyone explain the 1m40,1m35, etc.? Is this a reference to the distance of a concourse? like 1m40 = 1.40 meter? Thanks! --Ashley Rovira 19:35, 21 December 2006 (UTC)

Ya, ok, i cant let you discuss —Preceding unsigned comment added by Special:Contributions/ (talk)

There is separate article for hyphenated show-jumping. Can I suggest somebody who knows about the subject should try to combine the two articles into one.
 * To anonymous, I listed the pages at Duplicate articles also. Rmhermen 18:49, Dec 12, 2003 (UTC)

Technically this article is about Jumping in general, of which Show Jumping is one variety. Equitation and Hunter is even listed here. It's an important disinction since Jumping really does refer to all three, unfortunately its obviously an ambiguous term. Any suggestions as to a more succinct term which is still correct in the Equestrian world? --Domhail 09:13, 17 October 2005 (UTC)

Gem Twist
I know nothing about horses but when browsing this category and I clicked on Gem Twist's article. Previously it said this "Gem Twist Was the most famous of all show jumping horses. He was a German horse that was the first Stallion to complete a jump over 8ft high. He was a legend that lives on in many peoples hearts." While that may be true it's lacking a lot of information (not to mention oozing Point of View)! I added some basic information to the Gem Twist article and added the format that the other show jumping horse articles seem to have, but like I said it's lacking a lot of information. If you can fill this out please do so. -ImmortalGoddezz 06:30, 18 December 2005 (UTC)

POV Problem
The original article included the phrase "and the sheer spectacularity and thrill that no other sport can even come close to producing," in refernece to its popularity as an Olympic sport. While this may be true for those who are interested in or participate in equine sports, I feel it shows too much POV to be included. I've edited it out, but I'm open to discussion if someone can show otherwise. Consequentially 19:45, 26 April 2006 (UTC)

Laundry list elimination?
Might I propose we eliminate the "laundry list" of famous jumpers altogether? As you may have noticed, it is getting longer and longer, with plenty of room for disagreement.

In the alternative, I suggest someone creates a CATEGORY of "Show Jumpers" --or some similar title, link to it from this article, and then all show jumpers who have articles about them on wikipedia can be linked there instead of here.

My humble opinion is that most of the horse articles with these kinds of lists need to get rid of them both due to NPOV issues but also to fit the guidelines for a good wikipedia article. Comments? Montanabw 22:25, 24 November 2006 (UTC)

 * I agree with taking them off the Show jumping article. Have you not seen the category Showjumping horses witch these horses are already in!! As for getting 'rid' of them full stop, you would have to get 'rid' of the jockeys/riders as well, as the rider does not win Gold medals on his/her own. This is 'Wiki' they can be edited.

Culnacréann  23:33, 7 December 2006 (UTC)
 * I meant just in the show jumping article, not everywhere. Not paid much attention to the category, actually.    OK, so if I just toss out the whole list just in the show jumping article, does someone already have them listed elsewhere with appropriate links?  Just don't want to mess up something in my haste to make things neat and tidy! Montanabw 06:00, 8 December 2006 (UTC)
 * Categories: Famous horses & Showjumping horses are the only categories that link to Show jumping horses. Not all the show jumping horses were on the Show jumping page. Show jumping horses can be found by the Show jumping cat. link at the bottom of the Show jumping article. Culnacréann  16:10, 8 December 2006 (UTC)

OK, I guess that means it's OK for me to toss the laundry list in this article. If I messed up something, just fix it. Montanabw 20:12, 8 December 2006 (UTC)

Get it together, gang
Eventer and Culnacreann, I think you two are each putting in the rules for your own nation (i.e. US and Ireland/UK). How about just doing the FEI 2007 official rules and then split off sections for the varying rules for each nation, when different? And may I humbly suggest that CITATION to the actual rulebooks just might be the best long-term approach here? Montanabw (talk) 02:30, 25 September 2007 (UTC)

Tagging
IMHO, I think you overdid the tags on show jumping. The article does lack footnotes, but there ARE reference works. It does need a rewrite to be less confusing, perhaps, and I will be the first to agree it is far from GA status, but there have been some experienced riders working on the article, the "expert" tag doesn't seem appropriate, and I really don't see significant original research in there, either. (A lot of horse knowledge is, to this day, transmitted word of mouth and is widely known yet rarely published in books)  My thought is if you question material, slapping a "fact" tag on the questionable statements is preferable to an overall tag. My point is simply that a bunch of tags without any explanation is not going to improve this article much. (The original creator of the article IS pretty prone to not cite anything, even thougah I KNOW she's using references; I've mentioned this to her in the past, and have been ignored, so I'm OK with the "no footnotes" tag) It would be more helpful to tag it in specific trouble areas, keep the "confusing" tag if you wish, but place your specific concerns on the talk page. Montanabw (talk) 00:58, 23 December 2007 (UTC)

 * If it is not apparent to an experienced editor that the article is backed up by verifiable reliable sources, then it won't be apparent to a casual reader. The article reads more like a fan piece than a scientific article, and while word of mouth may be passing true information, it does NOT meet the Wikipedia policies regarding verifiability and neutrality.  If the editor of most fo tose articles is using references but refusing to cite, honestly, start removing her additions until she learns.  Ignoring corrections from other editors repeatedly regarding a core element of Wikipedia shouldn't be allowed to continue. The entire article needs clean up and overhaul from an expert in the field who also is well versed in properly writing and formatting an article for Wikipedia and the applicable policies and guidelines.  (Copied here from my talk page to address the request to list the concerns here). AnmaFinotera (talk) 02:02, 23 December 2007 (UTC)

 * Hmmm. No, I am not going to remove accurate material considered generally known knowledge just because it lacks a footnote. I'll wordsmith it, if I happen to have a good source for things I add, I try to footnote as I go because it's easier than footnoting later, but other people need to pull their share of the load. In the case of the individual in question, she has made extraordinary contributions to the horse articles here and put in countless hours, she knows her material; if she isn't good about digging a book out of the library that verifies what anyone in the field will verify if you ask, well, I may toss in a few cites when I get around to it, but it needs to get in my "rehab this article" queue and wait its turn--at the moment, I can think of five others ahead of it that are in more trouble than this one.  I've edited three articles up to GA status, coached a fourth and am thinking about putting up a fifth, but it was a lot of work and I really cannot pull the whole wagon here.

 * Are a few footnotes and two additional overall references is meaningless? Are you one of those people who feel that if there is not a footnote after every single paragraph that an article is unverifiable?   I ask this sincerely, as upon reviewing your contribution list it appears you are not a horse person and this particular article isn't really a beginner's topic.  I mean, I find Cryptographic hash function to be incomprehensible gibberish, but then, I am not a computer programmer or a cryptographer and wouldn't be starting there if what I was trying to learn more about basic cryptography.  I am also concerned about the "expert" tag because some of the people who worked on this article are probably "experts" on the topic, in that they do know what they are talking about and Wikipedians remain anonymous and don't file resumes.  You are correct that sometimes "expert in the field" and "experienced wikipedian" are not always one and the same and I don't disagree that the article is one of many in wikipedia that was written by a committee and suffers from some disorganization.

 * I think what I am going to do is tone down the tags a bit. See if you find my modifications acceptable.  It is a good thing to draw editor attention to an article that needs improvement, it is another to imply that the content is not accurate, which I think this series of tags did.   Montanabw (talk) 06:26, 23 December 2007 (UTC)

Horse murders article request
Hello, all --

I realize that this is a distasteful subject to many in the horse field, especially among those with a love of show jumpers, but the John Edwards and Rielle Hunter affair currently in the news has opened up many, many questions on the subject of the late 20th century horse murders scandal. The reason for that, in case you don't know, is that Rielle Hunter was formerly Lisa Druck, whose father, James Druck conspired to have her beloved show jumper Henry the Hawk electrocuted to collect the insurance money on him. This tragedy formed the backgtound for a 1988 novel based on Lisa Druck's life, called Story of my Life by Jay McInerney. Later, in the early to mid 1990s, the scandal was exposed to the public through articles in the New York imes and Sports Illustrated, and then through a full-length book called "Hot Blood. An FBI investifation into the horse murders led to the conviction of a number of highly placed people in the show jumper world on charges of insuracne fraud.

When Rielle Hunter's background was probed, due to her affair with John Edwards, it turned out that she and her horse were prominent victims of the horse murder insurance scam. But in trying to link this information up to her bio article, it turned up that there is no article on the subject of the horse murders at Wikipedia, doubtless because the scandal occured before the development of the world wide web. There is an article on the murder of the millionairess Helen Brach whose death, in 1977, was also connected to the horse murder scandal.

I am looking for a few good editors who have the brackground to write a horse murders article, and to link it to the Helen Brach, show jumping, and Rielle Hunter articles. No need to reply to me -- if you are interested, you know what to do. I will try to help, also, as best i can, but the topic is far from my usual fild of writing, and i would prefer to see it handled by those with the greatest depth of knowledge on the subject.

I am posting this identical request to a number of horse-rleated talk pages, so you may see it more than once, for which i apologize in advance.

Sincerely, catherine yronwode Catherineyronwode (talk) 02:38, 15 August 2008 (UTC)

Jumping, in general?
This article is about the sport of show jumping, and the related field of "hunters". Is there not an article that deals with horse jumping, generally? The biomechanics of it, etc. I know there is an article on bascule...If not, I propose one be started. Countercanter (talk) 17:23, 2 February 2009 (UTC)

 * Hi CC, what we have are the following: show jumping, show hunter, fox hunting, field hunter, and canter along with horse gait, lead change (which I opposed as a separate article, but lost), leaping gait and a few other horse show class articles about UK events.  I think an article on the biomechanics of jumping would be cool.  I think there is a redirect to this article called something like horse jumping or jumping (horse).  I think it would be cool if you wanted to start one.   Use canter or horse gait as a base, and don't forget to add cetegories and the animal locomotion template when it's up!   Montanabw (talk) 22:05, 2 February 2009 (UTC)

Show Names!
There isn't a section in here talking about how crazy we all get with figuring out show names for our mounts! There are usually really great funny stories behind them, and I think it would be a positive addition to the article. Granted, it's not just Show Jumpers, but why not? It's interesting where people come up with them —Preceding unsigned comment added by Sandere0 (talk • contribs) 18:37, 16 May 2011 (UTC)
 * That type of discussion should be kept in other forums, this talk page is meant for discussing about the corresponding Wikipedia article only. Pitke (talk) 19:36, 16 May 2011 (UTC)

Criticism, ethics, etc.
Many animal rights groups (credible as well as questionable) have criticized show jumping as unethical. If these claims are unfounded, discussion of why would be appropriate. If these assertions are however substantiated, a write up on this would be good also. — Preceding unsigned comment added by 115.188.14.114 (talk) 10:27, 31 July 2012 (UTC)

 * Hm. Never heard that before, criticism of some individual practices (poling, for example), but nothing about show jumping itself other than the usual "it's bad to ride horses at all - let them run wild and free" crowd.  Got a source?   Montanabw (talk) 16:16, 31 July 2012 (UTC)

I've not looked for any sources, and I like show jumping, but I was surprised to see a lack of criticism on this page as well. Horses may be strong, but they also weigh a ton, and jumping puts enormous stress on their legs. Some might say that it is an unnecessary stress. Plus, some professional competitors clearly don't have much regard for their horses [citation needed lel] in comparison for their desire to win. thefix.com Cian O'Connor For such as professional-looking page, shouldn't there be some mention of horse doping? — Preceding unsigned comment added by 68.100.138.56 (talk) 16:08, 6 February 2013 (UTC)

 * You are raising an issue that occurs across multiple disciplines, the issue of unethical competitors, drug use, and other forms of abuse. I guess my take is that there would be no problem with a small section on abuses specific to show jumping if we can find good WP:RS material on it.  However, your link to the Fix is not relevant, as the FEI cleaned up its act and the 2012 games were actually clean in the Equestrian events.  See here.  If you want to see how controversial abuse issues could be handled, probably the hottest-button article on wiki is Charreada, where you see a carefully crafted NPOV compromise that addresses the concerns with the views of both sides expressed. Unfortunately, it took more than half the article to do so there, though I think a simple paragraph here would be adequate.  A more suitable size in relation to the overall article (which is a long article, so the long section not so disproportionate) might be the section on soring at Tennessee_Walking_Horse.  We also have a more discipline-specific "controversies" section at Western_pleasure that is not fully sourced, but may be more of the tone we need here.   Montanabw (talk) 20:07, 6 February 2013 (UTC)

Let us find RS criticism. Zezen (talk) 03:07, 23 October 2019 (UTC)

External links modified
Hello fellow Wikipedians,

I have just added archive links to 3 one external links on Show jumping. Please take a moment to review my edit. If necessary, add after the link to keep me from modifying it. Alternatively, you can add to keep me off the page altogether. I made the following changes:
 * Added archive https://web.archive.org/20090116032856/http://www.rds.ie:80/horseshow/about/history.htm to http://www.rds.ie/horseshow/about/history.htm
 * Added archive https://web.archive.org/20130504092020/http://fei.org/sites/default/files/JumpRules_24thEd_2013_clean_updated_1.2.13.pdf to http://fei.org/sites/default/files/JumpRules_24thEd_2013_clean_updated_1.2.13.pdf
 * Added archive https://web.archive.org/20150403174422/http://www.showjumpinghalloffame.net/inductees/sjhf_inductees.shtml to http://www.showjumpinghalloffame.net/inductees/sjhf_inductees.shtml

When you have finished reviewing my changes, please set the checked parameter below to true to let others know.

Cheers. —cyberbot II  Talk to my owner :Online 00:28, 28 August 2015 (UTC)

World Record
Are there any members of wikipedia who know something about W.R., P.B. of some horses a.s.o. a.s.o. in Show Jumping ?! A world best list would be great... --Zwönitz (talk) 17:32, 8 November 2018 (UTC)

Article improvement
Rather than adding unsourced material with little discussion, Let’s figure out how to improve this article with more and better sourcing, wikilinking, and so on. Per WP:BRD, let’s discuss... Montanabw (talk) 00:10, 2 April 2020 (UTC)
 * I agree, I also see that not very many sources are listed in this article, I plan to add a few sources to improve the verifiability. WP:VERIFY Tepkunset (talk) 17:00, 7 May 2021 (UTC)

title: Talk:Show jumping


text:
Red Rider

Red Rider, later known as Tom Cochrane & Red Rider, is a Canadian rock band popular in the 1980s. While they achieved significant success in Canada, the band never had a song in the top 40 in the United States, although "Lunatic Fringe" from their second album, 1981's As Far as Siam, became popular on US album-oriented rock radio. They also charted on the Billboard Hot 100 with "White Hot" from their debut album Don't Fight It (1979) and "Young Thing, Wild Dreams (Rock Me)" from Breaking Curfew (1984), and charted comparably to "Lunatic Fringe" on Mainstream Rock (AOR) with "Big League", "Human Race", and "Power", the latter two tracks off 1983's Neruda.

As Red Rider
Red Rider was formed in Toronto in 1975 when Peter Boynton (keyboards, synthesizers, vocals), Ken Greer (guitars, keyboards, backing vocals) and Rob Baker (drums) joined up with Arvo Lepp (guitar) and Jon Checkowski (bass) and began playing around Toronto, performing both original and cover music.

In 1978, their manager at that time was contacted by Capitol Records about adding singer/guitarist/composer Tom Cochrane to the group. Cochrane was invited to one of the band's gigs in London, Ontario to rehearse with them. Boynton, Greer and Baker were impressed with his playing and songwriting but Lepp and Checkowski were not as enthused and decided to leave the band. Jeff Jones (formerly with Ocean and who briefly played for Rush) was then brought in on bass, and it was the lineup of Cochrane, Boynton, Greer, Baker and Jones that were signed to Capitol and released their first album Don't Fight It in October 1979. With the singles "White Hot" and "Don't Fight It", the album quickly reached gold status.

Their second album, As Far as Siam, was released in June 1981 and featured the hit "Lunatic Fringe", which featured steel guitarist Greer. The song was used in the 1985 movie Vision Quest, appeared in the Miami Vice episode "Smuggler's Blues" and saw high rotation on the United States cable network MTV. It is now a mainstay on American classic rock radio.

Peter Boynton was replaced by keyboardist Steve Sexton on Red Rider's third album Neruda, released in March 1983, and the track "Napoleon Sheds His Skin" would become one of the more popular songs from the album, while "Human Race" picked up considerable FM radio airplay in the US, becoming their second best known song there after "Lunatic Fringe". Moreover, the song "Can't Turn Back" was used in the Miami Vice episode "Tale of the Goat".

For their next release, Breaking Curfew (September 1984), John Webster (formerly with Canadian soft rockers Stonebolt) replaced Sexton on keyboards. The album did not sell as well as Neruda and a dispute with Bruce Allen, the band's manager, over the future direction of the band resulted in Red Rider's departure from the Bruce Allen camp and a change in band members, as Jeff Jones and Rob Baker left. The album did contain the band's top-charting single in the US, "Young Thing, Wild Dreams (Rock Me)", which reached number 71 on the Billboard Hot 100.

As Tom Cochrane & Red Rider
In what became a strong signal regarding the future of the band, they officially became known as Tom Cochrane & Red Rider. The line-up consisted of Cochrane, Greer and Webster with new member Ken "Spider" Sinnaeve on bass. For the first album under this revised name (their fifth overall), the group issued the self-titled Tom Cochrane and Red Rider LP in May 1986. Sessioneer Graham Broad (Go West and Roger Waters' band) played drums on the album, recorded in Wales at Rockfield Studios and Metalworks Studios in Mississauga, Ontario over the early months of 1985, produced by Patrick Moran. After the release of the album, Randall Coryell was added to the official lineup for live dates, as was guitarist Peter Mueller; this six-piece version of the band would last through early 1990.

In 1987 Capitol released a compilation CD titled Over 60 Minutes with Red Rider, covering the band's first four albums. Also in 1987, the band, who had been nominated 11 times for Juno Awards, finally was awarded one for Group of the Year.

In the fall of 1988, the band (now a sextet) released their sixth album, Victory Day, which contained the track "Big League", about the death of a young hockey player. The young man's father approached Cochrane on the day of a concert, mentioning that his son was a big fan of Red Rider's song "Boy Inside The Man". Cochrane asked the man if his son was going to be attending the concert and the man responded that his son had recently died in a car accident. Cochrane wrote the song as a memorial, and it became a big hit in Canada (reaching #4), as well as a top 10 hit on US rock radio.

Red Rider's final album, The Symphony Sessions, which was recorded on March 17 and 18, 1989, and released in December 1989, saw the band performing with the Edmonton Symphony Orchestra, as Procol Harum had done seventeen years before. The band broke up in early 1990, shortly after the album was released. Cochrane embarked on a successful solo career, employing Webster and Sinnaeve as part of his backing band.

The three-CD box set Ashes to Diamonds, which includes material by both Red Rider and Cochrane as a solo artist, was released in 1993.

Reformation (2002-present)
Cochrane, Greer, and Jones reunited as Red Rider in 2002 to play a benefit show after their 1980s guitar tech, John Garrish, was mugged and stabbed to death in the Yorkville section of Toronto. Since that time, Tom Cochrane and Red Rider have continued to tour annually, with Cochrane, Greer, and Jones being the mainstays of this revived version of the group. Keyboardist Webster was involved for a time between 2003 and 2006; current members Davide Direnzo (drums) and Bill Bell (guitar) both joined in 2006, though Bell dropped out for several years (2012-2016) before rejoining.

Professional wrestler Kurt Angle used an instrumental version of "Lunatic Fringe" as his entrance music in TNA. UFC fighter and former Pride Champion Dan "Hendo" Henderson also uses "Lunatic Fringe" as his intro song.

Members
Current members
 * Ken Greer – guitars, keyboards, backing vocals (1975–1990, 2002–present)
 * Tom Cochrane – vocals, guitar (1978–1990, 2002–present)
 * Jeff Jones – bass, backing vocals (1978–1985, 2002–present)
 * Davide Direnzo – drums (2006–present)
 * Bill Bell – guitar (2006-2011, 2017–present)

Former members
 * Rob Baker – drums (1975–1985)
 * Peter Boynton – keyboards, synthesizers, vocals (1975–1983)
 * Jon Checkowski – bass (1975–1978)
 * Arvo Lepp – guitar (1975–1978)
 * Steve Sexton - keyboards, synthesizers (1983-1984)
 * John Webster – keyboards, synthesizers (1984–1989, 2003–2006)
 * Ken "Spider" Sinnaeve – bass (1985–1990)
 * Randall Coryell – drums (1986–1990)
 * Peter Mueller – guitar (1988–1989)
 * Jamie Oakes – guitar (2002–2006)
 * Randall "Mongo" Stoll – drums (1998-2019)
 * Troy Feener – drums (2002–2006; 2009 – fill in for Direnzo)
 * Gary Craig – drums (2007 and 2009 – fill in for Direnzo)

Timeline

As Red Rider

 * Don't Fight It (1979)- Platinum in Canada
 * As Far as Siam (1981)- Platinum in Canada
 * Neruda (1983) Platinum in Canada
 * Breaking Curfew (1984)

Tom Cochrane & Red Rider

 * Tom Cochrane and Red Rider (1986) Platinum in Canada
 * Victory Day (1988) Platinum in Canada
 * The Symphony Sessions (1989) Platinum in Canada

Compilation albums

 * Over 60 Minutes with Red Rider (1987)
 * Ashes to Diamonds (1993)
 * Trapeze: The Collection (2002)

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

title: Red Rider


text:
Villahoz

Villahoz is a village and municipality in the Province of Burgos, Spain. The village is in the wine region known as Ribera del Arlanza, 15 km from Lerma.

title: Villahoz


text:
Measure-preserving dynamical system

In mathematics, a measure-preserving dynamical system is an object of study in the abstract formulation of dynamical systems, and ergodic theory in particular. Measure-preserving systems obey the Poincaré recurrence theorem, and are a special case of conservative systems. They provide the formal, mathematical basis for a broad range of physical systems, and, in particular, many systems from classical mechanics (in particular, most non-dissipative systems) as well as systems in thermodynamic equilibrium.

Definition
A measure-preserving dynamical system is defined as a probability space and a measure-preserving transformation on it. In more detail, it is a system

 * $$(X, \mathcal{B}, \mu, T)$$

with the following structure:

 * $$X$$ is a set,
 * $$\mathcal B$$ is a σ-algebra over $$X$$,
 * $$\mu:\mathcal{B}\rightarrow[0,1]$$ is a probability measure, so that $$\mu (X) = 1$$, and $$\mu(\varnothing) = 0$$,
 * $$ T:X \rightarrow X$$ is a measurable transformation which preserves the measure $$\mu$$, i.e., $$\forall A\in \mathcal{B}\;\; \mu(T^{-1}(A))=\mu(A) $$.

Discussion
One may ask why the measure preserving transformation is defined in terms of the inverse $$\mu(T^{-1}(A))=\mu(A)$$ instead of the forward transformation $$\mu(T(A))=\mu(A)$$. This can be understood intuitively.

Consider the typical measure on the unit interval $$[0, 1]$$, and a map $$Tx = 2x\mod 1 = \begin{cases} 2x \text{ if } x < 1/2 \\ 2x-1 \text{ if } x > 1/2 \\ \end{cases}$$. This is the Bernoulli map. Now, distribute an even layer of paint on the unit interval $$[0, 1]$$, and then map the paint forward. The paint on the $$[0, 1/2]$$ half is spread thinly over all of $$[0, 1]$$, and the paint on the $$[1/2, 1]$$ half as well. The two layers of thin paint, layered together, recreates the exact same paint thickness.

More generally, the paint that would arrive at subset $$A \subset [0, 1]$$ comes from the subset $$T^{-1}(A)$$. For the paint thickness to remain unchanged (measure-preserving), the mass of incoming paint should be the same: $$\mu(A) = \mu(T^{-1}(A))$$.

Consider a mapping $$\mathcal{T}$$ of power sets:
 * $$\mathcal{T}:P(X)\to P(X)$$

Consider now the special case of maps $$\mathcal{T}$$ which preserve intersections, unions and complements (so that it is a map of Borel sets) and also sends $$X$$ to $$X$$ (because we want it to be conservative). Every such conservative, Borel-preserving map can be specified by some surjective map $$T:X\to X$$ by writing $$\mathcal{T}(A)=T^{-1}(A)$$. Of course, one could also define $$\mathcal{T}(A)=T(A)$$, but this is not enough to specify all such possible maps $$\mathcal{T}$$. That is, conservative, Borel-preserving maps $$\mathcal{T}$$ cannot, in general, be written in the form $$\mathcal{T}(A)=T(A);$$.

$$\mu(T^{-1}(A))$$ has the form of a pushforward, whereas $$\mu(T(A))$$ is generically called a pullback. Almost all properties and behaviors of dynamical systems are defined in terms of the pushforward. For example, the transfer operator is defined in terms of the pushforward of the transformation map $$T$$; the measure $$\mu$$ can now be understood as an invariant measure; it is just the Frobenius–Perron eigenvector of the transfer operator (recall, the FP eigenvector is the largest eigenvector of a matrix; in this case it is the eigenvector which has the eigenvalue one: the invariant measure.)

There are two classification problems of interest. One, discussed below, fixes $$(X, \mathcal{B}, \mu)$$ and asks about the isomorphism classes of a transformation map $$T$$. The other, discussed in transfer operator, fixes $$(X, \mathcal{B})$$ and $$T$$, and asks about maps $$\mu$$ that are measure-like. Measure-like, in that they preserve the Borel properties, but are no longer invariant; they are in general dissipative and so give insights into dissipative systems and the route to equilibrium.

In terms of physics, the measure-preserving dynamical system $$(X, \mathcal{B}, \mu, T)$$ often describes a physical system that is in equilibrium, for example, thermodynamic equilibrium. One might ask: how did it get that way? Often, the answer is by stirring, mixing, turbulence, thermalization or other such processes. If a transformation map $$T$$ describes this stirring, mixing, etc. then the system $$(X, \mathcal{B}, \mu, T)$$ is all that is left, after all of the transient modes have decayed away. The transient modes are precisely those eigenvectors of the transfer operator that have eigenvalue less than one; the invariant measure $$\mu$$ is the one mode that does not decay away. The rate of decay of the transient modes are given by (the logarithm of) their eigenvalues; the eigenvalue one corresponds to infinite half-life.

Informal example
The microcanonical ensemble from physics provides an informal example. Consider, for example, a fluid, gas or plasma in a box of width, length and height $$w\times l\times h,$$ consisting of $$N$$ atoms. A single atom in that box might be anywhere, having arbitrary velocity; it would be represented by a single point in $$w\times l\times h\times \mathbb{R}^3.$$ A given collection of $$N$$ atoms would then be a single point somewhere in the space $$(w\times l\times h)^N \times \mathbb{R}^{3N}.$$ The "ensemble" is the collection of all such points, that is, the collection of all such possible boxes (of which there are an uncountably-infinite number). This ensemble of all-possible-boxes is the space $$X$$ above.

In the case of an ideal gas, the measure $$\mu$$ is given by the Maxwell–Boltzmann distribution. It is a product measure, in that if $$p_i(x,y,z,v_x,v_y,v_z)\,d^3x\,d^3p$$ is the probability of atom $$i$$ having position and velocity $$x,y,z,v_x,v_y,v_z$$, then, for $$N$$ atoms, the probability is the product of $$N$$ of these. This measure is understood to apply to the ensemble. So, for example, one of the possible boxes in the ensemble has all of the atoms on one side of the box. One can compute the likelihood of this, in the Maxwell–Boltzmann measure. It will be enormously tiny, of order $$\mathcal{O}\left(2^{-3N}\right).$$ Of all possible boxes in the ensemble, this is a ridiculously small fraction.

The only reason that this is an "informal example" is because writing down the transition function $$T$$ is difficult, and, even if written down, it is hard to perform practical computations with it. Difficulties are compounded if the interaction is not an ideal-gas billiard-ball type interaction, but is instead a van der Waals interaction, or some other interaction suitable for a liquid or a plasma; in such cases, the invariant measure is no longer the Maxwell–Boltzmann distribution. The art of physics is finding reasonable approximations.

This system does exhibit one key idea from the classification of measure-preserving dynamical systems: two ensembles, having different temperatures, are inequivalent. The entropy for a given canonical ensemble depends on its temperature; as physical systems, it is "obvious" that when the temperatures differ, so do the systems. This holds in general: systems with different entropy are not isomorphic.

Examples
[[Image:Exampleergodicmap.svg|thumb|Example of a ([[Lebesgue measure]]) preserving map: T : [0,1) → [0,1), $$x \mapsto 2x \mod 1.$$]] Unlike the informal example above, the examples below are sufficiently well-defined and tractable that explicit, formal computations can be performed.

 * μ could be the normalized angle measure dθ/2π on the unit circle, and T a rotation. See equidistribution theorem;
 * the Bernoulli scheme;
 * the interval exchange transformation;
 * with the definition of an appropriate measure, a subshift of finite type;
 * the base flow of a random dynamical system;
 * the flow of a Hamiltonian vector field on the tangent bundle of a closed connected smooth manifold is measure-preserving (using the measure induced on the Borel sets by the symplectic volume form) by Liouville's theorem (Hamiltonian);
 * for certain maps and Markov processes, the Krylov–Bogolyubov theorem establishes the existence of a suitable measure to form a measure-preserving dynamical system.

Generalization to groups and monoids
The definition of a measure-preserving dynamical system can be generalized to the case in which T is not a single transformation that is iterated to give the dynamics of the system, but instead is a monoid (or even a group, in which case we have the action of a group upon the given probability space) of transformations Ts : X → X parametrized by s ∈ Z (or R, or N ∪ {0}, or [0, +∞)), where each transformation Ts satisfies the same requirements as T above. In particular, the transformations obey the rules:
 * $$T_0 = \mathrm{id}_X :X \rightarrow X$$, the identity function on X;
 * $$T_{s} \circ T_{t} = T_{t + s}$$, whenever all the terms are well-defined;
 * $$T_{s}^{-1} = T_{-s}$$, whenever all the terms are well-defined.

The earlier, simpler case fits into this framework by defining Ts = Ts for s ∈ N.

Homomorphisms
The concept of a homomorphism and an isomorphism may be defined.

Consider two dynamical systems $$(X, \mathcal{A}, \mu, T)$$ and $$(Y, \mathcal{B}, \nu, S)$$. Then a mapping

 * $$\varphi:X \to Y$$

is a homomorphism of dynamical systems if it satisfies the following three properties:

 * 1) The map $$\varphi\ $$ is measurable.
 * 2) For each $$B \in \mathcal{B}$$, one has $$\mu (\varphi^{-1}B) = \nu(B)$$.
 * 3) For $\mu$-almost all $$x \in X$$, one has $$\varphi(Tx) = S(\varphi x)$$.

The system $$(Y, \mathcal{B}, \nu, S)$$ is then called a factor of $$(X, \mathcal{A}, \mu, T)$$.

The map $$\varphi\;$$ is an isomorphism of dynamical systems if, in addition, there exists another mapping

 * $$\psi:Y \to X$$

that is also a homomorphism, which satisfies

 * 1) for $$\mu$$-almost all $$x \in X$$, one has $$x = \psi(\varphi x)$$;
 * 2) for $$\nu$$-almost all $$y \in Y$$, one has $$y = \varphi(\psi y)$$.

Hence, one may form a category of dynamical systems and their homomorphisms.

Generic points
A point x ∈ X is called a generic point if the orbit of the point is distributed uniformly according to the measure.

Symbolic names and generators
Consider a dynamical system $$(X, \mathcal{B}, T, \mu)$$, and let Q = {Q1, ..., Qk} be a partition of X into k measurable pair-wise disjoint sets. Given a point x ∈ X, clearly x belongs to only one of the Qi. Similarly, the iterated point Tnx can belong to only one of the parts as well. The symbolic name of x, with regards to the partition Q, is the sequence of integers {an} such that

 * $$T^nx \in Q_{a_n}.$$

The set of symbolic names with respect to a partition is called the symbolic dynamics of the dynamical system. A partition Q is called a generator or generating partition if μ-almost every point x has a unique symbolic name.

Operations on partitions
Given a partition Q = {Q1, ..., Qk} and a dynamical system $$(X, \mathcal{B}, T, \mu)$$, define the T-pullback of Q as

 * $$ T^{-1}Q = \{T^{-1}Q_1,\ldots,T^{-1}Q_k\}.$$

Further, given two partitions Q = {Q1, ..., Qk} and R = {R1, ..., Rm}, define their refinement as

 * $$ Q \vee R = \{Q_i \cap R_j \mid i=1,\ldots,k,\ j=1,\ldots,m,\ \mu(Q_i \cap R_j) > 0 \}.$$

With these two constructs, the refinement of an iterated pullback is defined as

\begin{align} \bigvee_{n=0}^N T^{-n}Q & = \{Q_{i_0} \cap T^{-1}Q_{i_1} \cap \cdots \cap T^{-N}Q_{i_N} \\ & {} \qquad \mbox { where }i_\ell = 1,\ldots,k ,\ \ell=0,\ldots,N,\ \\ & {} \qquad \qquad \mu \left (Q_{i_0} \cap T^{-1}Q_{i_1} \cap \cdots \cap T^{-N}Q_{i_N} \right )>0 \} \\ \end{align} $$

which plays crucial role in the construction of the measure-theoretic entropy of a dynamical system.

Measure-theoretic entropy
The entropy of a partition $$\mathcal{Q}$$ is defined as

 * $$H(\mathcal{Q})=-\sum_{Q \in \mathcal{Q}}\mu (Q) \log \mu(Q).$$

The measure-theoretic entropy of a dynamical system $$(X, \mathcal{B}, T, \mu)$$ with respect to a partition Q = {Q1, ..., Qk} is then defined as

 * $$h_\mu(T,\mathcal{Q}) = \lim_{N \rightarrow \infty} \frac{1}{N} H\left(\bigvee_{n=0}^N T^{-n}\mathcal{Q}\right).$$

Finally, the Kolmogorov–Sinai metric or measure-theoretic entropy of a dynamical system $$(X, \mathcal{B},T,\mu)$$ is defined as

 * $$h_\mu(T) = \sup_{\mathcal{Q}} h_\mu(T,\mathcal{Q}).$$

where the supremum is taken over all finite measurable partitions. A theorem of Yakov Sinai in 1959 shows that the supremum is actually obtained on partitions that are generators. Thus, for example, the entropy of the Bernoulli process is log 2, since almost every real number has a unique binary expansion. That is, one may partition the unit interval into the intervals [ 0, 1/2 ) and [1/2, 1]. Every real number x is either less than 1/2 or not; and likewise so is the fractional part of 2nx.

If the space X is compact and endowed with a topology, or is a metric space, then the topological entropy may also be defined.

If $$T$$ is an ergodic, piecewise expanding, and Markov on $$X \subset \R$$, and $$\mu$$ is absolutely continuous with respect to the Lebesgue measure, then we have the Rokhlin formula (section 4.3 and section 12.3 ):$$h_{\mu }(T) = \int \ln |dT/dx| \mu(dx) $$This allows calculation of entropy of many interval maps, such as the logistic map.

Ergodic means that $$T^{-1}(A) = A$$ implies $$A$$ has full measure or zero measure. Piecewise expanding and Markov means that there is a partition of $$X$$ into finitely many open intervals, such that for some $$\epsilon > 0$$, $$|T'| \geq 1 + \epsilon$$ on each open interval. Markov means that for each $$I_i$$ from those open intervals, either $$T(I_i) \cap I_i = \emptyset $$ or $$T(I_i) \cap I_i = I_i $$.

Classification and anti-classification theorems
One of the primary activities in the study of measure-preserving systems is their classification according to their properties. That is, let $$(X, \mathcal{B}, \mu)$$ be a measure space, and let $$U$$ be the set of all measure preserving systems $$(X, \mathcal{B}, \mu, T)$$. An isomorphism $$S\sim T$$ of two transformations $$S, T$$ defines an equivalence relation $$\mathcal{R}\subset U\times U.$$ The goal is then to describe the relation $$\mathcal{R}$$. A number of classification theorems have been obtained; but quite interestingly, a number of anti-classification theorems have been found as well. The anti-classification theorems state that there are more than a countable number of isomorphism classes, and that a countable amount of information is not sufficient to classify isomorphisms.

The first anti-classification theorem, due to Hjorth, states that if $$U$$ is endowed with the weak topology, then the set $$\mathcal{R}$$ is not a Borel set. There are a variety of other anti-classification results. For example, replacing isomorphism with Kakutani equivalence, it can be shown that there are uncountably many non-Kakutani equivalent ergodic measure-preserving transformations of each entropy type.

These stand in contrast to the classification theorems. These include:
 * Ergodic measure-preserving transformations with a pure point spectrum have been classified.
 * Bernoulli shifts are classified by their metric entropy.  See Ornstein theory for more.

title: Measure-preserving dynamical system


text:
Meninges

In anatomy, the meninges (, : meninx ( or  ),  ) are the three membranes that envelop the brain and spinal cord. In mammals, the meninges are the dura mater, the arachnoid mater, and the pia mater. Cerebrospinal fluid is located in the subarachnoid space between the arachnoid mater and the pia mater. The primary function of the meninges is to protect the central nervous system.

Dura mater
The dura mater (tough mother), is a thick, durable membrane, closest to the skull and vertebrae. The dura mater, the outermost part, is a loosely arranged, fibroelastic layer of cells, characterized by multiple interdigitating cell processes, no extracellular collagen, and significant extracellular spaces. The middle region is a mostly fibrous portion. It consists of two layers: the endosteal layer, which lies closest to the skull, and the inner meningeal layer, which lies closer to the brain. It contains larger blood vessels that split into the capillaries in the pia mater. It is composed of dense fibrous tissue, and its inner surface is covered by flattened cells like those present on the surfaces of the pia mater and arachnoid mater. The dura mater is a sac that envelops the arachnoid mater and surrounds and supports the large dural sinuses carrying blood from the brain toward the heart.

The dura has four areas of infolding:
 * Falx cerebri, the largest, sickle-shaped; separates the cerebral hemispheres. Starts from the frontal crest of frontal bone and the crista galli running to the internal occipital protuberance.
 * Tentorium cerebelli, the second largest, crescent-shaped; separates the occipital lobes from cerebellum. The falx cerebri attaches to it giving a tentlike appearance.
 * Falx cerebelli, vertical infolding; lies inferior to the tentorium cerebelli, separating the cerebellar hemispheres.
 * Diaphragma sellae, smallest infolding; covers the pituitary gland and sella turcica.

Arachnoid mater
The middle element of the meninges is the arachnoid mater, or arachnoid membrane, so named because of its resemblance to a spider web. It cushions the central nervous system. This thin, transparent membrane is composed of fibrous tissue and, like the pia mater, has an outer layer of tightly packed flat cells, forming the arachnoid barrier.

The shape of the arachnoid does not follow the convolutions of the surface of the brain and so looks like a loosely fitting sac. In particular, in the region of the brain a large number of fine filaments called arachnoid trabeculae pass from the arachnoid through the subarachnoid space to blend with the tissue of the pia mater. The arachnoid barrier has no extracellular collagen and is considered to represent an effective morphological and physiological meningeal barrier between the cerebrospinal fluid in the subarachnoid space and the blood circulation in the dura.

The arachnoid barrier layer is characterized by a distinct continuous basal lamina on its inner surface toward the innermost collagenous portion of the arachnoid reticular layer.

Pia mater
The pia mater (tender mother) is a very delicate membrane. It is the meningeal envelope that firmly adheres to the surfaces of the brain and spinal cord, following all of the brain's contours (gyri and sulci). It is a very thin membrane composed of fibrous tissue covered on its outer surface by a sheet of flat cells thought to be impermeable to fluid. The pia mater is pierced by blood vessels to the brain and spinal cord, and its capillaries nourish the brain.

Leptomeninges
The arachnoid and pia mater are sometimes together called the leptomeninges, literally "thin meninges" (λεπτός "leptos"—"thin"). Acute meningococcal meningitis can lead to an exudate within the leptomeninges along the surface of the brain. Because the arachnoid is connected to the pia by cob-web like strands, it is structurally continuous with the pia, hence the name pia-arachnoid or leptomeninges. They are responsible for the production of beta-trace protein (prostaglandin D2 synthase), a major cerebrospinal fluid protein.

Subarachnoid space
The subarachnoid space is the space that normally exists between the arachnoid and the pia mater. It is filled with cerebrospinal fluid and continues down the spinal cord. Spaces are formed from openings at different points along the subarachnoid space; these are the subarachnoid cisterns, which are filled with cerebrospinal fluid.

The dura mater is attached to the skull, whereas in the spinal cord, the dura mater is separated from the vertebrae by a space called the epidural space, which contains fat and blood vessels. The arachnoid is attached to the dura mater, while the pia mater is attached to the central nervous system tissue. When the dura mater and the arachnoid separate through injury or illness, the space between them is the subdural space. There is a subpial space underneath the pia mater that separates it from the glia limitans.

Clinical significance
Injuries involving the meninges, can result in a hemorrhage and two types of hematoma.
 * A subarachnoid hemorrhage is acute bleeding under the arachnoid; it may occur spontaneously or as a result of trauma.
 * A subdural hematoma is a hematoma (collection of blood) located in a separation of the arachnoid from the dura mater. The bridging veins that connect the dura mater and the arachnoid are torn, usually during an accident, and blood leaks into this area.
 * An epidural hematoma, bleeding between the dura mater and the skull, may arise after an accident or spontaneously.

Other medical conditions that affect the meninges include meningitis (usually from a fungal, bacterial, or viral infection) and meningiomas that arise from the meninges, or from meningeal carcinomatoses (tumors) that form elsewhere in the body and metastasize to the meninges.

Other animals
In fish, there is a single membrane known as the primitive meninx. Amphibians and reptiles have two meninges, and birds and mammals have three. In the early 1900s, Giuseppe Sterzi, an Italian anatomist, carried out comparative studies on the meninges from the lancelet to the human. Contrary to previous reports, the spinal meninges were seen to be very simple, both in the adult lower vertebrates and in the early developmental stages of the more advanced vertebrates. From the mesenchyme surrounding the neural tube, only a single leaflet forms the primitive meninx. In the following phylogenetic and ontogenetic stages, the latter divides into an internal leaflet: the secondary meninx, and into an external one: the dura mater. Finally, in higher vertebrates, even the secondary meninx divides into the arachnoid and the pia. In the same animals, Sterzi demonstrated that, while in the spinal medulla the dura keeps its identity, in the skull it fuses with the periosteum. He also demonstrated the continuity of all meninges with the envelopes of nerves and with the filum terminale.

Mammals (as higher vertebrates) retain the dura mater, and the secondary meninx divides into the arachnoid and pia mater.

title: Meninges


text:
Redwall (novel)

Redwall is a fantasy novel by Brian Jacques. Originally published in 1986, it is the first book of the Redwall series. The book was illustrated by Gary Chalk, with the British cover illustration by Pete Lyon and the US cover by Troy Howell. It is also one of the three Redwall novels to be made into an animated television series (which is aired on PBS, but produced by the Canadian studio), along with Mattimeo (Season 2) and Martin the Warrior (Season 3).

Plot summary
A young anthropomorphic mouse named Matthias is a novice monk at Redwall Abbey, where he was adopted as a young orphan, though he dreams of a life of adventure, inspired by the legends of Martin the Warrior, the founder of Redwall. One summer, Redwall Abbey is surrounded by the army of Cluny the Scourge, an infamously evil one-eyed rat. Matthias is guided by visions of Martin the Warrior, while the abbey inhabitants prepare the defense of their home against Cluny's impending attack. Matthias seeks Martin's famous sword, supposedly hidden somewhere within the abbey, helped particularly by Methuselah, an ancient and grizzled mouse who serves as Redwall's historian. Cluny, meanwhile, attempts to gain entrance to the abbey and murders a defector from his horde, Sela the red fox. Sela's son, Chickenhound, seeks refuge at Redwall but ends up accidentally killing Methuselah after being caught stealing. Driven from the abbey, Chickenhound is maimed in the wilderness by the venomous adder Asmodeus Poisonteeth, a local terror in Mossflower Wood, the forest that surrounds the abbey.

Clues to the location of Martin's sword and shield have been built into the abbey, allowing Matthias to recover the shield, though he discovers the sword has been stolen by a wild house sparrow tribe, the Sparras, that dwell on Redwall's roof. He learns from the violent sparrows that the sword was stolen from them in turn by Asmodeus. The king of the sparrows attacks Matthias but dies when the two plummet together off the abbey roof. Matthias recovers and ventures to Asmodeus's lair with his new allies Log-a-Log, a shrew, and Warbeak Sparra, the new and just queen of the aforementioned Sparras. Matthias, Log-a-Log, and two other Shrews succeed in retrieving the sword from Asmodeus's cave, Asmodeus kills the latter two, and Matthias subsequently kills Asmodeus. Alerted to the fall of the abbey by the Sparra tribe, Matthias rushes back to Redwall to save his friends.

The Redwall inhabitants have been using boiling water, oil, barrels of hornets, and fire to repel Cluny's horde, but the abbey finally falls when Cluny threatens the family of the gatekeeper, who allows Cluny's forces access to the abbey. Matthias, his allies now including the Mossflower shrews and the whole Sparra tribe, along with the newly captive Redwall population, battles against Cluny's minions. Cluny strikes his poison-barb tail at the father abbot, Mortimer, but Matthias quickly avenges the abbot's injury by dropping the abbey's giant bell on top of Cluny, crushing him to death and cracking the bell in the process. Abbot Mortimer proclaims Matthias the Warrior of Redwall and dies from his wound. The battle ends in victory for the defenders of Redwall.

An epilogue reveals that Matthias has married the fieldmouse Cornflower and she has given birth to their son, Mattimeo, an abbreviated version of the name Matthias Methuselah Mortimer. The cracked Joseph Bell has been reshaped into two new bells called Matthias and Methuselah.

Discrepancies
As Redwall was the first book set in the Redwall world, many of its defining traits were not yet developed, and are different from all subsequent books in the series:

The world

 * Redwall appeared to take place in the real world. Cluny was referred to as a Portuguese water rat at one point. Additionally, Methuselah claimed that one of the accounts of Cluny comes from a town dog. The horse present in the early chapters was the size of a normal horse, and the wagon it pulled was scaled to the same size – an entire army of rats was able to ride in it. Also there was a mention of cows that trampled through a village. However, Brian Jacques did not expect the book to be published, and excluded references to humans and many larger animals in later books.
 * Aside from the setting of the story—an Abbey with an abbot but no apparent religious observances—the St. Ninian's Church is the only reference to any kind of religion in any of the Redwall series, implying that at one point the residents of Mossflower practised Christianity. (Although later in the series, it is rumoured that originally, the sign outside the church said "This ain't Ninian's!", and some of the letters wore away.) Jacques firmly stated that the inhabitants of Redwall Abbey practice no religion of any kind. Cluny and his soldiers also mention Satan ("by Satan's nose" or "Hell's teeth"), referring to a belief in Hell. No other religious mentionings have happened in any of the later books. However, evil characters sometimes use the word "Hellgates" as a reference to death or dying. Dark Forest's Gates, or just Dark Forest refers to a place that characters' souls go after death.

Species discrepancy

 * Redwall is the only book in the entire series that makes any mention of domesticated animals. Animals mentioned in this book – but never again in the series – include horse, dog, cow, and pig. Additionally, the Abbot mentions a "village where the dog and pigs reside", perhaps implying human habitation. In the books following this, the world of Redwall is inhabited only by wild fauna. However, in Eulalia! an owl refers to a cow in a song he sings. Moreover, various kinds of milks and cheeses are consumed by the inhabitants of Redwall, though no direct description of such farming or manufacture is ever made.
 * The beaver in Redwall is the only one to appear in the entire series. Its species has not been mentioned since.
 * Bees can communicate in Redwall, indicated by a statement at the end of the book where the Guerilla Shrews learned to speak the bee language so they could trade and argue. This was not noted in other books.
 * Foxes are indicated in Redwall as not inherently evil. It is mentioned that Abbot Mortimer used to trade tomes with "wandering healer foxes". Sela the vixen's brood of foxes was referred to as a bad lot, indicating that they were an exception and not the norm. In all later books, foxes are a "vermin" species.
 * Brother Methuselah mentions that it was Martin who gave the first Foremole his title; however, in Mossflower, Foremole is already known as such before Martin's arrival, though this is most likely because Mossflower, Martin's debut book, was published after Redwall.
 * In Redwall, the cat is scaled to real life compared to Matthias and Constance the Badger is depicted pulling a cart by herself, but in later books, badgers and wildcats are roughly the size of the other animals (if large).
 * In Redwall, Guosim was a character, a member of the Guerilla Shrews. In later books, the shrews themselves were referred to as the Guosim, and no mention of the character Guosim was made, even in Mattimeo. The Shrews did not rename themselves after her, either, indicated by the fact that they were referred to as Guosim in books chronologically earlier than Redwall. Furthermore, while the shrews appear in Redwall as an independent tribe with no alliance with the other "good" creatures, in books chronologically earlier they are shown as frequent allies. Log-a-Log, in addition, is always shown as their chief, while he is a mere ferry-shrew in Redwall. The customs of the tribe also changed dramatically: In Redwall the Guosim are democratic and the actions of the tribe are carried out by votes. In the books following, there is no voting, in fact the actions of the tribe fall primarily on the chieftain's decision. (However, it is unofficially mentioned in Redwall that "Guosim" stands for "Guerilla Union of Shrews in Mossflower."

Awards and nominations
Winner: Nominated:
 * Lancashire Libraries Children's Book of the Year Award
 * Western Australian Young Readers' Award
 * Carnegie Medal

Publication history
Select print publications:
 * 1986, UK, Hutchinson Children's Books Ltd., ISBN 0-09-165090-9, Pub. Date: October 1986, Hardback
 * 1987, USA, Philomel Books, ISBN 0-399-21424-0, Pub. Date: August 1987, Hardback
 * 1987, UK, Red Fox, ISBN 0-09-951200-9, Pub. Date: September 1987, Paperback
 * 1990, USA, Avon Books, ISBN 0-380-70827-2, Pub. Date: March 1990, Paperback
 * 1997, USA, G P Putnam's Sons, ISBN 0-399-23160-9, Pub. Date: September 1997, Hardback
 * 1998, USA, Ace, ISBN 0-441-00548-9, Pub. Date: June 1998, Paperback
 * 2002, USA, Thorndike Press, ISBN 0-7862-3858-5, Pub. Date: February 2002, Hardback
 * 2002, UK, Penguin Putnam Books, ISBN 0-14-230237-6, Pub. Date: September 2002, Paperback

Graphic novel
Redwall has been adapted into a graphic novel, titled Redwall: The Graphic Novel. It was released on 4 October 2007.

Musical
Redwall was adapted into a musical called Redwall: The Legend of Redwall Abbey, along with a cast of actors.

Proposed film adaptation
In February 2021, Netflix announced an animated feature film adaptation. It will be based on the self-titled first book of the novels and its script penned by Patrick McHale. In November 2022, McHale announced that he finished the script, but due to the changes at Netflix Animation, McHale left the project only a month later.

title: Redwall (novel)


text:
10 Things I Hate About You

10 Things I Hate About You is a 1999 American teen romantic comedy film directed by Gil Junger in his film directorial debut and starring Julia Stiles, Heath Ledger, Joseph Gordon-Levitt, and Larisa Oleynik. The screenplay by Karen McCullah Lutz and Kirsten Smith is a modernization of William Shakespeare's comedy The Taming of the Shrew, retold in a late-1990s American high school setting. The film follows new student Cameron James (Gordon-Levitt) who is smitten with Bianca Stratford (Oleynik) and attempts to get bad boy Patrick Verona (Ledger) to date her antisocial sister Kat (Stiles) in order to get around her father's strict rules on dating. Named after a poem Kat writes about her romance with Patrick, the film was mostly shot in the Seattle metropolitan area, with many scenes filmed at Stadium High School in Tacoma, Washington.

Released on March 31, 1999, 10 Things I Hate About You grossed over $60 million and received generally positive reviews from critics. It provided breakthrough roles for Stiles, Ledger, and Gordon-Levitt, all of whom were nominated for various teen-oriented awards. Ten years later, it was adapted into a television reboot, which ran for 20 episodes and featured Larry Miller reprising his role as Walter Stratford.

Plot
Cameron James, a new student at Padua High School in the Seattle area, immediately becomes smitten with beautiful and popular sophomore Bianca Stratford. Geeky Michael Eckman warns him that she is vapid and conceited, and that her overprotective single father Walter, an obstetrician worried about teenage pregnancy, does not allow her or her shrewish older sister Kat, a senior, to date. Kat is accepted to Sarah Lawrence College in New York, but Walter wants her to stay close to home and attend his alma mater, the University of Washington. Bianca wishes to date affluent senior Joey Donner, but Walter will not allow his daughters to date until they graduate. Frustrated by Bianca's insistence and Kat's rebelliousness, Walter relents and declares that Bianca may date only when Kat does, knowing that Kat's antisocial attitude will greatly complicate it.

When Cameron asks Bianca out, she informs him of her father's new rule and suggests he find someone willing to date Kat so that she can freely date Joey. He selects Australian "bad boy" Patrick Verona, who initially frightens him with his attitude. Michael assists by convincing Joey to pay Patrick to take Kat out, believing that it will allow Joey to date Bianca. Patrick agrees to the deal, but Kat initially rebuffs his first few advances. After Michael and Cameron assist him by probing Bianca for information on Kat's preferences, Patrick begins to win Kat's interest. She goes to a party with him, which enables Bianca to tag along, greatly upsetting Walter.

At the party, Kat becomes upset upon seeing Bianca with Joey, and responds by getting intoxicated. Patrick attends to her, and she starts to open up to him, expressing her interest in forming a band. When Kat attempts to kiss him, Patrick pulls away, causing her to depart, infuriated. Meanwhile, Bianca upsets Cameron by ignoring him for Joey, but soon realizes that Joey is indeed shallow and self-absorbed. When she asks Cameron to drive her home, he admits his feelings for her are indeed genuine and her treatment of him has frustrated him, and she reconciliatorily kisses him in response.

Joey offers to pay Patrick to take Kat to the prom so he can take Bianca. He initially refuses, but relents when Joey offers him more money. Although Kat is still angry with Patrick, he eventually wins her over by serenading her, accompanied by the Padua High School marching band, with a performance of "Can't Take My Eyes Off You" by Frankie Valli, and she returns the favor by assisting him in sneaking out of detention. Their subsequent date turns romantic, but Kat becomes suspicious when Patrick insists that she accompany him to the prom, which she adamantly opposes.

Irritated at not being asked to the prom by Cameron, Bianca accepts Joey's invitation, but Walter declines to allow it unless Kat accompanies her. Kat confesses to Bianca that she dated Joey when they were freshmen and, succumbing to peer pressure, had sexual intercourse with him, later regretting it. After Joey dumped her, she vowed against doing anything out of peer pressure. Bianca insists that she can decide her own life, so Kat agrees to attend the prom with Patrick, and Bianca decides to go with Cameron instead of Joey. At the prom, Bianca learns that Joey planned to have sexual intercourse with her that night. Angry that Bianca has spurned him for Cameron, Joey reveals his arrangement with Patrick, which causes Kat to leave, heartbroken. Joey then shoves Michael and punches Cameron, but Bianca then assaults him for having hurt her, Kat, and Cameron. Bianca and Cameron share another kiss.

The following day, Bianca reconciles with Kat and begins dating Cameron. Comfortable that Kat can handle herself, Walter permits her to attend Sarah Lawrence College. For an assignment in which the students were tasked to write their own versions of William Shakespeare's Sonnet 141, Kat reads aloud a poem she composed, entitled "10 Things I Hate About You", revealing that she still loves and cares for Patrick. He surprises her with a Fender Stratocaster that he bought with the money Joey paid him, and confesses that he has fallen for her. Kat forgives him, and they reconcile with a kiss.

Cast

 * Julia Stiles as Katarina "Kat" Stratford, the antisocial, shrewish elder Stratford sister
 * Heath Ledger as Patrick Verona, the Australian "bad boy" hired to date Kat
 * Joseph Gordon-Levitt (credited as Joseph-Gordon Levitt) as Cameron James, the new student at Padua High School who is smitten with Bianca and goes to great lengths to win her over
 * Larisa Oleynik as Bianca Stratford, the younger Stratford sister, superficial and popular
 * Larry Miller as Walter Stratford, an obstetrician and single parent who is overprotective of his daughters
 * Andrew Keegan as Joey Donner, an affluent, self-absorbed high school senior and aspiring model who intends to have sex with Bianca, and to that end pays Patrick to date Kat
 * David Krumholtz as Michael Eckman, a geek who assists Cameron in his quest to woo Bianca, and in the process tries to woo Kat's friend Mandella
 * Susan May Pratt as Mandella, Kat's only close friend and an aficionado of William Shakespeare who falls for Michael
 * Daryl "Chill" Mitchell as Mr. Morgan, teacher of Kat, Patrick, and Joey's English class
 * Allison Janney as Ms. Perky, Padua High School's guidance counselor and a writer of erotic literature
 * David Leisure as Mr. Chapin, coach of the girls' soccer team
 * Gabrielle Union as Chastity Church, Bianca's best friend who later becomes her enemy
 * Greg Jackson as "Scurvy", a friend of Patrick
 * Kyle Cease as Bogey Lowenstein, a golf enthusiast and member of a clique of aspiring MBAs
 * The band Letters to Cleo (singer Kay Hanley, guitarists Greg McKenna and Michael Eisenstein, bassist Scott Riebling, and drummer Jason Sutter) appears as the band performing at Club Skunk, playing their songs "Come On" and "Co-Pilot", and a cover of Cheap Trick's "I Want You to Want Me" on the school's rooftop during the closing credits. Hanley and Eisenstein also appear in the prom scene, performing a cover of Nick Lowe's "Cruel to Be Kind" with Save Ferris.
 * The band Save Ferris (singer Monique Powell, guitarist Brian Mashburn, bassist Bill Uechi, trumpeter José Castellaños, trombonist Brian Williams, saxophonist Eric Zamora, and drummer Evan Kilbourne) appears as the band performing at the prom, playing their songs "I Know" and "Can't Stop" as well as covers of The Isley Brothers' "Shout" and Nick Lowe's "Cruel to Be Kind".

Production
The script was finalized in November 1997. Many of the scenes were filmed on location at Stadium High School and at a house in the North End of Tacoma, Washington. The prom sequence was shot over three days in Seattle. Costume designer Kim Tillman designed original dresses for Oleynik and Stiles, as well as the period outfits for Pratt and Krumholtz. Union's snakeskin prom dress is a Betsey Johnson design. Ledger's and Gordon-Levitt's vintage tuxes came from Isadora's in Seattle. For the scene where Patrick dances on the high school bleachers, Ledger took inspirations from Showgirls and Fred Astaire. Filming took place from June 8 to August 6, 1998.

Josh Hartnett and Ashton Kutcher were in the running to play Patrick. Eliza Dushku auditioned for the role of Kat. Katie Holmes was also considered for the role. Kate Hudson was offered the part but her mother, Goldie Hawn, did not like the script, so she passed on the role.

Box office
In its opening weekend, the film grossed $8.3 million in 2,271 theaters domestically (averaging $3,668 per venue), finishing second at the box office, behind The Matrix. It grossed a total of $38.2 million in the U.S. and Canada, and $15.3 million in other territories, for $53.5 million worldwide.

Critical response
On review aggregator Rotten Tomatoes, the film holds an approval rating of 71% based on 92 reviews, with an average rating of 6.3/10. The website's critics consensus states: "Julia Stiles and Heath Ledger add strong performances to an unexpectedly clever script, elevating 10 Things (slightly) above typical teen fare." Metacritic assigned the film a weighted average score of 70 out of 100, based on 26 critics, indicating "generally favorable reviews". Audiences polled by CinemaScore gave the film an average grade of "B" on an A+ to F scale.

Geoff Andrew from Time Out praised the film's leads, writing, "Stiles grows into her character, and Ledger is effortlessly charming." Brad Laidman of Film Threat said the film was "pure of heart and perfectly executed." Ron Wells, also of Film Threat, wrote, "Of all the teen films released this year, this one is, by far, the best." Roger Ebert gave the film two and a half stars out of four, saying that he "liked the movie's spirit, the actors and some of the scenes. The music, much of it by the band Letters to Cleo, is subtle and inventive while still cheerful. The movie almost but not quite achieves liftoff against the gravitational pull of the tired story formula." Entertainment Weekly put the film 49th on its list of Best High School Movies.

Accolades
10 Things I Hate About You provided breakthrough roles for Stiles, Ledger, and Gordon-Levitt. Gordon-Levitt, Stiles, and Oleynik each received Young Star Award nominations for Best Actor/Actress in a Comedy Film. The movie was nominated for seven Teen Choice Awards: Choice Movie: Breakout Star (Stiles), Choice Movie: Comedy, Choice Movie: Funniest Scene (featuring Krumholtz), Choice Movie: Love Scene (featuring Stiles and Ledger), Choice Movie: Hissy Fit (Gordon-Levitt), Choice Movie: Villain (Andrew Keegan) and Choice Movie: Soundtrack. The film's casting directors Marcia Ross and Donna Morong won "Best Casting for Feature Film, Comedy" at the Casting Society of America in 1999. In 2000, Stiles won the CFCA Award for Most Promising Actress (tied with Émilie Dequenne in Rosetta) and an MTV Movie Award for Breakthrough Female Performance. Ledger was also nominated for an MTV Movie Award for Best Musical Performance for the song "Can't Take My Eyes Off You".

Soundtrack
The film's soundtrack album, featuring Letters to Cleo performing cover versions of Cheap Trick's "I Want You to Want Me" and Nick Lowe's "Cruel to Be Kind", stayed on the Billboard 200 chart for seven weeks, peaking at no. 52. Reviewer S. Peeples of AllMusic rated it 3 stars out of 5, calling it "one of the best modern rock soundtracks of the spring 1999 season".

Adaptations
In June 1999, the Scholastic Corporation published a novelization of the story, adapted by David Levithan. The story is retold as it is in the film, with each chapter written from the point of view of either Bianca, Cameron, Kat, Patrick, or Michael.

In October 2008, ABC Family ordered a pilot episode of 10 Things I Hate About You, a half-hour, single-camera comedy series based on the film. Larry Miller is the only actor from the film to reprise his role in the TV series. The director of the film, Gil Junger, directed many of the episodes, including the pilot; the film's composer, Richard Gibbs, also returned to do the show's music. The series was adapted and produced by Carter Covington. The show premiered on July 7, 2009, and ended on May 24, 2010, lasting 20 episodes.

title: 10 Things I Hate About You


text:
Paresthesia

Paresthesia is an abnormal sensation of the skin (tingling, pricking, chilling, burning, numbness) with no apparent physical cause. Paresthesia may be transient or chronic, and may have many possible underlying causes. Paresthesias are usually painless and can occur anywhere on the body, but most commonly occur in the arms and legs.

The most familiar kind of paresthesia is the sensation known as "pins and needles" after having a limb "fall asleep". A less well-known and uncommon paresthesia is formication, the sensation of insects crawling on the skin.

Transient

Paresthesias of the hands, feet, legs, and arms are common transient symptoms. The briefest electric shock type of paresthesia can be caused by tweaking the ulnar nerve near the elbow; this phenomenon is colloquially known as bumping one's "funny bone". Similar brief shocks can be experienced when any other nerve is tweaked (e.g. a pinched neck nerve may cause a brief shock-like paresthesia toward the scalp). In the older age group, spinal column irregularities may tweak the spinal cord briefly when the head or back is turned, flexed, or extended into brief uncommon positions (Lhermitte's sign).

The most common everyday cause is temporary restriction of nerve impulses to an area of nerves, commonly caused by leaning or resting on parts of the body such as the legs (often followed by a pins and needles tingling sensation). Other causes include conditions such as hyperventilation syndrome and panic attacks. A cold sore outside the mouth (not a canker sore inside the mouth) can be preceded by tingling due to activity of the causative herpes simplex virus. The varicella zoster virus (shingles) also notably may cause recurring pain and tingling in skin or tissue along the distribution path of that nerve (most commonly in the skin, along a dermatome pattern, but sometimes feeling like a headache, chest or abdominal pain, or pelvic pain).

Other common examples occur when sustained pressure has been applied over a nerve, inhibiting or stimulating its function. Removing the pressure typically results in gradual relief of these paresthesias. Most pressure-induced paraesthesia results from awkward posture, such as engaging in cross-legged sitting for prolonged periods of time.

Reactive hyperaemia, which occurs when blood flow is restored after a period of ischemia, may be accompanied by paresthesia, e.g. when patients with Raynaud's disease rewarm after a cold episode.

Cases of paresthesia have also been reported at varying frequencies following anthrax, flu, HPV and COVID-19  vaccine intake.

Chronic
Chronic paresthesia (Berger's paresthesia, Sinagesia, or Bernhardt paresthesia) indicates either a problem with the functioning of neurons, or poor circulation.

In older individuals, paresthesia is often the result of poor circulation in the limbs (such as in peripheral vascular disease), most often caused by atherosclerosis, the build-up of plaque within artery walls over decades, with eventual plaque ruptures, internal clots over the ruptures, and subsequent clot healing, but leaving behind narrowing or closure of the artery openings, locally and/or in downstream smaller branches. Without a proper supply of blood and nutrients, nerve cells can no longer adequately send signals to the brain. Because of this, paresthesia can also be a symptom of vitamin deficiency or other malnutrition, as well as metabolic disorders like diabetes, hypothyroidism, or hypoparathyroidism. It can also be a symptom of mercury poisoning.

Irritation to the nerve can also come from inflammation to the tissue. Joint conditions such as rheumatoid arthritis, psoriatic arthritis, and carpal tunnel syndrome are common sources of paresthesia. Nerves below the head may be compressed where chronic neck and spine problems exist, and can be caused by, among other things, muscle cramps that may be a result of clinical anxiety or excessive mental stress, bone disease, poor posture, unsafe heavy lifting practices, or physical trauma such as whiplash. Paresthesia can also be caused simply by putting pressure on a nerve by applying weight (or pressure) to the limb for extended periods of time.

Another cause of paresthesia may be direct damage to the nerves themselves, i.e., neuropathy, which itself can stem from injury, such as from frostbite; infections such as Lyme disease; or may be indicative of a current neurological disorder. Neuropathy is also a side effect of some chemotherapies, such as in the case of chemotherapy-induced peripheral neuropathy. Benzodiazepine withdrawal may also cause paresthesia, as the drug removal leaves the GABA receptors stripped bare and possibly malformed. Chronic paresthesia can sometimes be symptomatic of serious conditions, such as a transient ischemic attack; or autoimmune diseases such as multiple sclerosis, complex regional pain syndrome, or lupus erythematosus. The use of fluoroquinolones can also cause paresthesia. Stroke survivors and those with traumatic brain injury (TBI) may experience paresthesia from damage to the central nervous system.

The varicella zoster virus disease (shingles) can attack nerves, causing numbness instead of the pain commonly associated with shingles.

Acroparesthesia
Acroparesthesia is severe pain in the extremities, and may be caused by Fabry disease, a type of sphingolipidosis.

It can also be a sign of hypocalcemia.

Dentistry
Dental paresthesia is loss of sensation caused by maxillary or mandibular anesthetic administration before dental treatment.

Potential causes include trauma introduced to the nerve sheath during administration of the injection, hemorrhage about the sheath, more side-effect-prone types of anesthetic being used, or administration of anesthetic contaminated with alcohol or sterilizing solutions.

Other
Other causes may include:

 * Autonomous sensory meridian response ("ASMR")
 * Carpal tunnel syndrome
 * Cerebral amyloid angiopathy
 * Chiari malformation
 * Coeliac disease
 * Complex regional pain syndrome
 * Cubital tunnel syndrome
 * Decompression sickness
 * Dehydration
 * Erythromelalgia
 * Fabry disease
 * Fibromyalgia
 * Fluoroquinolone toxicity
 * Guillain–Barré syndrome (GBS)
 * Heavy metals
 * Herpes zoster
 * Hydroxy alpha sanshool, a component of Sichuan peppers
 * Hyperglycemia (high blood sugar)
 * Hyperkalemia
 * Hyperventilation
 * Hypocalcemia, and in turn:
 * Hypermagnesemia, a condition in which hypocalcemia itself is typically observed as a secondary symptom
 * Hypoglycemia (low blood sugar)
 * Hypothyroidism
 * Immunodeficiency, such as chronic inflammatory demyelinating polyneuropathy (CIDP)
 * Intravenous administering of strong pharmaceutical drugs acting on the central nervous system (CNS), mainly opiates, opioids, or other narcotics, especially in non-medical use (drug abuse)
 * Lupus erythematosus
 * Lyme disease
 * Magnesium deficiency, often as a result of long-term proton-pump inhibitor use
 * Megavitamin-B6 syndrome
 * Menopause
 * Mercury poisoning
 * Migraines
 * Multiple sclerosis
 * Nerve compression syndrome
 * Obdormition
 * Oxygen toxicity, especially breathing oxygen under pressure, such as in scuba diving
 * Pyrethrum or pyrethroid pesticides
 * Post-polio syndrome
 * Rabies
 * Radiation poisoning
 * Sarcoidosis
 * Scorpion stings
 * Spinal disc herniation or injury
 * Spinal stenosis
 * Stinging nettles
 * Syringomyelia
 * Transverse myelitis
 * Variant Creutzfeldt–Jakob disease (AKA "mad cow disease")
 * Vitamin B5 deficiency
 * Vitamin B12 deficiency
 * Withdrawal from certain selective serotonin reuptake inhibitors (AKA serotonin-specific reuptake inhibitors or SSRIs), such as paroxetine, or serotonin-norepinephrine reuptake inhibitors (SNRIs), such as venlafaxine

Drugs

 * Anticonvulsant pharmaceutical drugs, such as topiramate, sultiame, or acetazolamide
 * Benzodiazepine withdrawal syndrome
 * Beta alanine
 * Dextromethorphan (recreational use)
 * Ketorolac
 * Lidocaine poisoning
 * Lomotil
 * Nitrous oxide, long-term exposure
 * Ritonavir

Diagnostics
A nerve conduction study usually provides useful information for making a diagnosis. An MRI or a CT scan is sometimes used to rule out certain causes stemming from central nervous system issues.

Treatment
Medications offered can include the immunosuppressant prednisone, intravenous gamma globulin (IVIG), anticonvulsants such as gabapentin or tiagabine, or antiviral medication, depending on the underlying cause.

In addition to treatment of the underlying disorder, palliative care can include the use of topical numbing creams, such as lidocaine or prilocaine. Ketamine has also been successfully used, but is generally not approved by insurance. Careful consideration must be taken to apply only the necessary amount, as excess can contribute to these conditions. Otherwise, these products generally offer extremely effective, but short-lasting relief from these conditions.

Paresthesia caused by stroke may receive some temporary benefit from high doses of baclofen multiple times a day. HIV patients who self-medicate with cannabis report that it reduces their symptoms.

Paresthesia caused by shingles is treated with appropriate antiviral medication.

Etymology
The word paresthesia (British English paraesthesia; plural paraesthesiae or paraesthesias) comes from the Greek para ("beside", i.e., abnormal) and aisthesia ("sensation").

title: Paresthesia


text:
Ryanggang Province

Ryanggang Province (Ryanggangdo;, ) is a province in North Korea. The province is bordered by China (Jilin) to the north, North Hamgyong to the east, South Hamgyong to the south, and Chagang to the west. Ryanggang was formed in 1954, when it was separated from South Hamgyŏng. The provincial capital is Hyesan. In South Korean usage, "Ryanggang" is spelled and pronounced as "Yanggang", ).

Description
Along the northern border with China runs the Yalu River and the Tumen River. In between the rivers, and the source of both, is Paektu Mountain, revered by both the Koreans and Manchurians as the mythic origin of each people. The North Korean government claims that Kim Jong-il was born there when his parents were at a Communist anti-Japanese resistance camp at the mountain. The North Korean-Chinese border for 20 mi east of the mountain is "dry, remote and mountainous, barely patrolled," making it one of the crossing areas for refugees from North Korea into China, although most, including refugees from Ryanggang itself, prefer to cross over the Tumen River.

Although all of North Korea is economically depressed after Soviet dissolution, Ryanggang province, along with neighboring North Hamgyong and South Hamgyong provinces, are the poorest, forming North Korea's "Rust Belt" of industrialized cities with factories now decrepit and failing. The worst hunger of the 1990s famine years occurred in these three provinces, and most refugees into China come from the Rust Belt region.

Ryanggang explosion
An explosion and mushroom cloud was reportedly detected in Kimhyŏngjik-gun on 9 September 2004, the 56th anniversary of the creation of North Korea. This was reported a few days later on 12 September.

Power supply issues
In recent years, power supply problems have become prevalent in Ryanggang.

Administrative divisions
Ryanggang is divided into 2 cities (si) and 10 counties (kun). Each entity is listed below in English, Chosŏn'gŭl, and Hanja.

title: Ryanggang Province


text:
Shaken baby syndrome

Shaken baby syndrome (SBS), also known as abusive head trauma (AHT), is a medical condition in children younger than five years old, generally caused by blunt trauma, vigorous shaking, or a combination of both. SBS is the leading cause of fatal head injuries in children under two, with a risk of death of about 25%. The most common symptoms include retinal bleeds, multiple fractures of the long bones, and subdural hematomas (bleeding in the brain).

The condition is often caused as a result of a parent or caregiver becoming frustrated due to the child crying. Diagnosis can be difficult as symptoms may be nonspecific. A CT scan of the head is typically recommended if a concern is present. If there are concerning findings on the CT scan, a full work-up for child abuse should occur, including an eye exam and skeletal survey. Retinal hemorrhage is highly associated with AHT, occurring in 78% of cases of AHT versus 5% of cases of non-abusive head trauma.

Diagnosing the syndrome has proven to be both challenging and contentious for medical professionals because objective witnesses to the initial trauma are generally unavailable. This is said to be particularly problematic when the trauma is deemed 'non-accidental'. Some medical professionals propose that SBS is the result of respiratory abnormalities leading to hypoxia and swelling of the brain. The courtroom has become a forum for conflicting theories with which generally accepted medical literature has not been reconciled. Often there are no outwardly visible signs of trauma, despite the presence of severe internal brain and eye injury. Complications include seizures, visual impairment, cerebral palsy, cognitive impairment, and death.

Educating new parents appears to be beneficial in decreasing rates of the condition. SBS is estimated to occur in three to four per 10,000 babies a year. These signs have evolved through the years as accepted and recognized signs of child abuse. Medical professionals strongly suspect shaking as the cause of injuries when a young child presents with retinal bleed, fractures, soft tissue injuries, or subdural hematoma that cannot be explained by accidental trauma or other medical conditions.

Retinal hemorrhage (bleeding) occurs in around 85% of SBS cases and the severity of retinal hemorrhage correlates with severity of head injury. The type of retinal bleeds are often believed to be particularly characteristic of this condition, making the finding useful in establishing the diagnosis.

Fractures of the vertebrae, long bones, and ribs may also be associated with SBS. Dr. John Caffey reported in 1972 that metaphyseal avulsions (small fragments of bone torn off where the periosteum covering the bone and the cortical bone are tightly bound together) and "bones on both the proximal and distal sides of a single joint are affected, especially at the knee".

Infants may display irritability, failure to thrive, alterations in eating patterns, lethargy, vomiting, seizures, bulging or tense fontanelles (the soft spots on a baby's head), increased size of the head, altered breathing, and dilated pupils.

Risk factors
Caregivers that are at risk for becoming abusive often have unrealistic expectations of the child and may display "role reversal", expecting the child to fulfill the needs of the caregiver. Substance abuse and emotional stress, resulting for example from financial troubles, are other risk factors for aggression and impulsiveness in caregivers. Caregivers of any gender can cause SBS. Although it had been previously speculated that SBS was an isolated event, evidence of prior child abuse is a common finding. In an estimated 33–40% of cases, evidence of prior head injuries, such as old intracranial bleeds, is present.

Mechanism
Effects of SBS are thought to be diffuse axonal injury, oxygen deprivation and swelling of the brain, which can raise pressure inside the skull and damage delicate brain tissue, although witnessed shaking events have not led to such injuries.

Traumatic shaking occurs when a child is shaken in such a way that its head is flung backwards and forwards. In 1971, Guthkelch, a neurosurgeon, hypothesized that such shaking can result in a subdural hematoma, in the absence of any detectable external signs of injury to the skull. The article describes two cases in which the parents admitted that for various reasons they had shaken the child before it became ill. Moreover, one of the babies had retinal hemorrhages. The association between traumatic shaking, subdural hematoma and retinal hemorrhages was described in 1972 and referred to as whiplash shaken infant syndrome. The injuries were believed to occur because shaking the child subjected the head to acceleration–deceleration and rotational forces.

Force
There has been controversy regarding the amount of force required to produce the brain damage seen in SBS. There is broad agreement, even amongst skeptics, that shaking of a baby is dangerous and can be fatal.

A biomechanical analysis by F. A. Bandak published in 2005 reported that "forceful shaking can severely injure or kill an infant, this is because the cervical spine would be severely injured and not because subdural hematomas would be caused by high head rotational accelerations... an infant head subjected to the levels of rotational velocity and acceleration called for in the SBS literature, would experience forces on the infant neck far exceeding the limits for structural failure of the cervical spine. Furthermore, shaking cervical spine injury can occur at much lower levels of head velocity and acceleration than those reported for SBS." Other authors were critical of the mathematical analysis by Bandak, citing concerns about the calculations the author used concluding "In light of the numerical errors in Bandak's neck force estimations, we question the resolute tenor of Bandak's conclusions that neck injuries would occur in all shaking events." Other authors critical of the model proposed by Bandak concluding "the mechanical analogue proposed in the paper may not be entirely appropriate when used to model the motion of the head and neck of infants when a baby is shaken." Bandak responded to the criticism in a letter to the editor published in Forensic Science International in February 2006.

Diagnosis
Diagnosis can be difficult as symptoms may be nonspecific. A CT scan of the head is typically recommended if a concern is present. It is unclear how useful subdural haematoma, retinal hemorrhages, and encephalopathy are alone at making the diagnosis.

Triad
While the findings of SBS are complex and many, they are often incorrectly referred to as a "triad" for legal proceedings; distilled down to retinal hemorrhages, subdural hematomas, and encephalopathy.

SBS may be misdiagnosed, underdiagnosed, and overdiagnosed, and caregivers may lie or be unaware of the mechanism of injury. Commonly, there are no externally visible signs of the condition. Examination by an experienced ophthalmologist is critical in diagnosing shaken baby syndrome, as particular forms of ocular bleeding are strongly associated with AHT. Magnetic resonance imaging may also depict retinal hemorrhaging but is much less sensitive than an eye exam. Conditions that are often excluded by clinicians include hydrocephalus, sudden infant death syndrome (SIDS), seizure disorders, and infectious or congenital diseases like meningitis and metabolic disorders. CT scanning and magnetic resonance imaging are used to diagnose the condition. Conditions that often accompany SBS/AHT include classic patterns of skeletal fracturing (rib fractures, corner fractures), injury to the cervical spine (in the neck), retinal hemorrhage, cerebral bleed or atrophy, hydrocephalus, and papilledema (swelling of the optic disc).

The terms non-accidental head injury or inflicted traumatic brain injury have been used in place of "abusive head trauma" or "SBS".

Classification
The US Centers for Disease Control and Prevention identifies SBS as "an injury to the skull or intracranial contents of an infant or young child (< 5 years of age) due to inflicted blunt impact and/or violent shaking". In 2009, the American Academy of Pediatrics recommended the use of the term abusive head trauma (AHT) to replace SBS, in part to differentiate injuries arising solely from shaking and injuries arising from shaking as well as trauma to the head.

The Crown Prosecution Service for England and Wales recommended in 2011 that the term shaken baby syndrome be avoided and the term non accidental head injury (NAHI) be used instead.

Vitamin C deficiency
Some authors have suggested that certain cases of suspected shaken baby syndrome may result from vitamin C deficiency. This contested hypothesis is based upon a speculated marginal, near scorbutic condition or lack of essential nutrient(s) repletion and a potential elevated histamine level. However, symptoms consistent with increased histamine levels, such as low blood pressure and allergic symptoms, are not commonly associated with scurvy as clinically significant vitamin C deficiency. A literature review of this hypothesis in the journal Pediatrics International concluded the following: "From the available information in the literature, concluded that there was no convincing evidence to conclude that vitamin C deficiency can be considered to be a cause of shaken baby syndrome."

The proponents of such hypotheses often question the adequacy of nutrient tissue levels, especially vitamin C, for those children currently or recently ill, bacterial infections, those with higher individual requirements, those with environmental challenges (e.g. allergies), and perhaps transient vaccination-related stresses. At the time of this writing, infantile scurvy in the United States is practically nonexistent. No cases of scurvy mimicking SBS or sudden infant death syndrome have been reported, and scurvy typically occurs later in infancy, rarely causes death or intracranial bleeding, and is accompanied by other changes of the bones and skin and invariably an unusually deficient dietary history.

In one study vaccination was shown not associated with retinal hemorrhages.

Gestational problems
Gestational problems affecting both mother and fetus, the birthing process, prematurity and nutritional deficits can accelerate skeletal and hemorrhagic pathologies that can also mimic SBS, even before birth.

Prevention
Interventions by neonatal nurses include giving parents information about abusive head trauma, normal infant crying and reasons for crying, teaching how to calm an infant, and how to cope if the infant was inconsolable may reduce rates of SBS.

Treatment
Treatment involves monitoring intracranial pressure (the pressure within the skull). Treatment occasionally requires surgery, such as to place a cerebral shunt to drain fluid from the cerebral ventricles, and, if an intracranial hematoma is present, to drain the blood collection.

Prognosis
Prognosis depends on severity and can range from total recovery to severe disability to death when the injury is severe. One third of these patients die, one third survives with a major neurological condition, and only one third survives in good condition; therefore shaken baby syndrome puts children at risk of long-term disability. The most frequent neurological impairments are learning disabilities, seizure disorders, speech disabilities, hydrocephalus, cerebral palsy, and visual disorders.

Epidemiology
Small children are at particularly high risk for the abuse that causes SBS given the large difference in size between the small child and an adult. SBS usually occurs in children under the age of two but may occur in those up to age five. In the US, deaths due to SBS constitute about 10% of deaths due to child abuse.

History
In 1971, Norman Guthkelch proposed that whiplash injury caused subdural bleeding in infants by tearing the veins in the subdural space. The term "whiplash shaken infant syndrome" was introduced by Dr. John Caffey, a pediatric radiologist, in 1973, describing a set of symptoms found with little or no external evidence of head trauma, including retinal bleeds and intracranial bleeds with subdural or subarachnoid bleeding or both. Development of computed tomography and magnetic resonance imaging techniques in the 1970s and 1980s advanced the ability to diagnose the syndrome.

Legal issues
The association of diagnosed SBS with deliberate assault is a matter of legal and medical contention, with conflicting opinions as to whether one necessarily implies the other.

The President's Council of Advisers on Science and Technology (PCAST) noted in its September 2016 report that there are concerns regarding the scientific validity of forensic evidence of abusive head trauma that "require urgent attention". Similarly, the Maguire model, suggested in 2011 as a potential statistical model for determining the probability that a child's trauma was caused by abuse, has been questioned. A proposed clinical prediction rule with high sensitivity and low specificity, to rule out Abusive Head Trauma, has been published.

In July 2005, the Court of Appeal of England and Wales heard four appeals of SBS convictions: one case was dropped, the sentence was reduced for one, and two convictions were upheld. The court found that the classic triad of retinal bleeding, subdural hematoma, and acute encephalopathy are not 100% diagnostic of SBS and that clinical history is also important. In the Court's ruling, they upheld the clinical concept of SBS but dismissed one case and reduced another from murder to manslaughter. In their words: "Whilst a strong pointer to NAHI [non-accidental head injury] on its own we do not think it possible to find that it must automatically and necessarily lead to a diagnosis of NAHI. All the circumstances, including the clinical picture, must be taken into account."

The court did not believe the "unified hypothesis", proposed by British physician J. F. Geddes and colleagues, as an alternative mechanism for the subdural and retinal bleeding found in suspected cases of SBS. The unified hypothesis proposed that the bleeding was not caused by shearing of subdural and retinal veins but rather by cerebral hypoxia, increased intracranial pressure, and increased pressure in the brain's blood vessels. The court reported that "the unified hypothesis [could] no longer be regarded as a credible or alternative cause of the triad of injuries": subdural haemorrhage, retinal bleeding and encephalopathy due to hypoxemia (low blood oxygen) found in suspected SBS.

On 31 January 2008, the Wisconsin Court of Appeals granted Audrey A. Edmunds a new trial based on "competing credible medical opinions in determining whether there is a reasonable doubt as to Edmunds's guilt." Specifically, the appeals court found that "Edmunds presented evidence that was not discovered until after her conviction, in the form of expert medical testimony, that a significant and legitimate debate in the medical community has developed in the past ten years over whether infants can be fatally injured through shaking alone, whether an infant may suffer head trauma and yet experience a significant lucid interval prior to death, and whether other causes may mimic the symptoms traditionally viewed as indicating shaken baby or shaken impact syndrome."

In 2012, Norman Guthkelch, the neurosurgeon often credited with "discovering" the diagnosis of SBS, published an article "after 40 years of consideration," which is harshly critical of shaken baby prosecutions based solely on the triad of injuries. Again, in 2012, Guthkelch stated in an interview, "I think we need to go back to the drawing board and make a more thorough assessment of these fatal cases, and I am going to bet ... that we are going to find in every – or at least the large majority of cases, the child had another severe illness of some sort which was missed until too late." Furthermore, in 2015, Guthkelch went so far as to say, "I was against defining this thing as a syndrome in the first instance. To go on and say every time you see it, it's a crime... It became an easy way to go into jail."

Teri Covington, who runs the National Center for Child Death Review Policy and Practice, worries that such caution has led to a growing number of cases of child abuse in which the abuser is not punished.

In March 2016, Waney Squier, a paediatric neuropathologist who has served as an expert witness in many shaken baby trials, was struck off the medical register for misconduct. Shortly after her conviction, Squier was given the "champion of justice" award by the International Innocence Network for her efforts to free those wrongfully convicted of shaken baby syndrome.

Squier denied the allegations and appealed the decision to strike her off the medical register. As her case was heard by the High Court of England and Wales in October 2016, an open letter to the British Medical Journal questioning the decision to strike off Squier, was signed by 350 doctors, scientists, and attorneys. On 3 November 2016, the court published a judgment which concluded that "the determination of the MPT [Medical Practitioners Tribunal] is in many significant respects flawed". The judge found that she had committed serious professional misconduct but was not dishonest. She was reinstated to the medical register but prohibited from giving expert evidence in court for the next three years.

In 2022, Channel 4 in the UK broadcast a documentary called The Killer Nanny: Did She Do It? concerning the Louise Woodward case. In it, civil rights lawyer Clive Stafford Smith stated, "shaken baby syndrome is bullshit".

title: Shaken baby syndrome