Pathfinder Wiki - User contributions [en]

AY Honors/Plastic Canvas/Answer Key

2007-08-20T11:08:48Z

68.3.53.1: tidying up

'''Worsted''' is the name of a [[yarn]], the [[cloth]] made from this yarn, as well as a yarn weight category. The name derives from the village of [[Worstead]] in the [[England|English]] county of [[Norfolk]]. This village became, along with [[North Walsham]] and [[Aylsham]], a centre for the manufacture of yarn and cloth after weavers from [[Flanders]] arrived in Norfolk in the 12th century.<ref>''[http://www.worstead.co.uk/history_village.htm Worstead village history]''. Retrieved [[December 15]], [[2005]].</ref>

==Technique & Preparation==

The essential feature of a worsted yarn is straightness of fibre, in that the fibres lie parallel to each other. Traditionally, long, fine [[Staple (textiles)|staple]] [[wool]] was [[Spinning (textiles)|spun]] to create worsted yarn, but other long [[fibre]]s are also used today.

Many spinners differentiate between worsted preparation and worsted spinning. Worsted preparation refers to the way the fibre is prepared before spinning, using combs to force the fibre staples to lie parallel to each other. This produces overlapping untwisted strands called "slivers". Worsted spinning refers to using a worsted technique, which produces a smooth yarn with no air. Combinations of worsted preparation and worsted spinning with other techniques produce different types of yarn, notably semi-worsted yarn.

A [[roving]] is often used to spin wooolen yarn, and top is often used to spin worsted yarn. Many hand spinners buy their fibre in roving or top form. Top and roving are rope like in appearance, in that they can be thick and long. While some mills put a slight twist in the rovings they make, it is not enough twist to be a yarn. The fibers in top all lie parallel to one another along the length, which makes top ideal for spinning worsted yarns. The fibers in roving all lie crossed to one another along the length, which makes roving ideal for spinning woolen yarns.

Contrast [[woolen]].

==The cloth==

Worsted cloth, archaically also known as "stuff", is lightweight and has a coarse texture. The [[weaving|weave]] is usually [[twill]] or plain. Twilled fabrics such as [[whipcord]], [[gabardine]] and [[serge]] are often made from worsted yarn. Worsted fabric made from wool has a natural recovery, meaning that it is resilient and quickly returns to its natural shape, but non-glossy worsted will shine with use or abrasion.

Worsteds differs from [[woolen]]s, in that the natural crimp of the wool fibre is removed in the process of spinning the yarn. In Tropical Worsteds, this use of tightly-spun straightened wool, combined with a looser weave, permits the free flow of air through the fabric.

Worsted is also used for [[carpet]]s, [[Clothing|garments]], [[hosiery]], [[glove]]s, and [[baize]].

==Weight==

The term "worsted" is often applied to any yarn spun from fibres three inches in length or longer that have been carded or combed, and spun, not just wool. [[Acrylic fiber|Acrylic]] and other yarns can be called "worsted," and this is a reference to the weight of the yarn as much as the production process.

A worsted yarn generally has a [[gauge (knitting)|gauge]] of about 16-20 stitches per 10 centimeters using US size 9 needles, though this definition may vary slightly in different countries.

==History==

Prior to the introduction of automatic machinery there was little difficulty in attaining a straight fibre, as long wool was always used, and the sliver was made up by hand, using combs. However, with the introduction of [[Richard Arkwright]]'s [[water frame]] in 1771, and the later introduction of cap and mule spinning machines, the need for perfectly prepared slivers became apparent, and many [[factory|manufactories]] used one or more preparatory "gill-boxes" (combing machines) before the worsting process, to ensure straightness of fibre and even distribution of the [[lubricant]].

== References ==
<references />
*{{1911}}

==External Links==
*[http://www.yarnstandards.com/weight.html Standard Yarn Weight System] - Lists recommended needles sizes, gauge, etc. for the various yarn weight categories.

<BR>

{{Template:Spinning}}
[[Category:Spinning]]
[[Category:Woven fabrics]]

[[de:Kammgarn]]

AY Honors/Species Account/Negaprion brevirostris

2007-07-08T16:52:07Z

68.3.53.1:

{{Taxobox
| color = pink
| name = Lemon shark
| status = LR/nt
| trend = unknown
| image = Lemon shark.png
| image_width = 200px
| regnum = [[Animal]]ia
| phylum = [[Chordata]]
| classis = [[Chondrichthyes]]
| subclassis = [[Elasmobranchii]]
| ordo = [[Carcharhiniformes]]
| familia = [[Carcharhinidae]]
| genus = ''[[Negaprion]]''
| species = '''''N. brevirostris'''''
| binomial = ''Negaprion brevirostris''
| binomial_authority = ([[Felipe Poey|Poey]], [[1868]])
}}
{{Sharksportal}}

The '''lemon shark''', ''Negaprion brevirostris'', is a well studied [[shark]] belonging to the family [[Carcharhinidae]].

==Distribution and habitat==
It is found mainly along the [[subtropical]] and [[tropical]] parts of the [[Atlantic Ocean|Atlantic]] coast of [[North America|North]] and [[South America]]. This species can be found as well in Pacific islands of Polynesia - French Polynesia - Tahiti, Cook Islands, Tongas.

==Reproduction==
Lemon sharks are [[viviparous]], females giving birth to between 4 and 17 young every other year in warm and shallow lagoons. The young have to fend for themselves and remain in shallow water near [[mangrove]]s until they grow larger. With increasing size, the sharks venture further away from their birth place. At maturity at a size of 1.5 to 2 [[metre|m]] and an age of 12 to 15 years, they leave shallow water and move into deeper waters offshore. However, little is known of this life stage. Maximum recorded length and weight is 340 [[centimetre|cm]] and 183 [[kilogram|kg]].[http://fishbase.sinica.edu.tw/summary/SpeciesSummary.php?id=897]

Recent work in [[genetics]] by Drs Kevin Feldheim, Sonny Gruber and Mary Ashley may suggest that adult sharks move over hundreds of [[kilometre|km]] to mate, or populations far apart may have been separated in recent time. Further research in this area would be of immense importance for the understanding of the lemon shark's breeding behaviour and ecology.

==Importance to humans==
[[Image:ZitronenhaiWorld.png|thumb|left|200px|Range of ''N. brevirostris'']]
Lemon sharks are a popular choice for study by scientists as they survive well in captivity, unlike many other species such as [[Great White Shark|great white sharks]], which die in captivity because they refuse food. The species is the best known of all sharks in terms of behaviour and [[ecology]], mainly thanks to the enormous effort of Dr. Samuel Gruber at the [[University of Miami]] who has been studying the lemon shark both in the field and in the laboratory since 1967. The population around the [[Bimini Islands]] in the western [[Bahamas]], where Dr Gruber's field station, Bimini Biological Field Station, is situated, is probably the best known of all shark populations. As of 2007, it is experiencing a severe population decline and may disappear altogether due to destruction of the mangroves for construction of a golf [[resort]].

==See also==
* [[List of sharks]]

==References==
* {{IUCN2006|assessors=Gruber & Sundström|year=2000|id=39380|title=Negaprion brevirostris|downloaded=11 May 2006}} Database entry includes justification for why this species is near threatened
* {{ITIS|ID=160433|taxon=Negaprion brevirostris|year=2006|date=23 January}}
* {{FishBase_species|genus=Negaprion|species=brevirostris|year=2005|month=March}}
* ''Washington Post'', 2005, Aug. 22nd: "Scientists Fear Oceans on the Cusp Of a Wave of Marine Extinctions"

==External links==
{{commons|Negaprion brevirostris|Lemon shark}}
* [http://www.sharkdiving.us/lemonshark.html Lemon shark facts and pictures]

[[Category:Sharks]]
[[Category:Viviparous fish]]
[[Category:Carcharhinidae]]

[[cs:Žralok citrónový]]
[[de:Zitronenhai]]
[[fr:Requin citron]]
[[nl:Citroenhaai]]
[[sk:Žralok citrónový]]
[[fi:Sitruunahai]]
[[sv:Citronhaj]]

AY Honors/Species Account/Negaprion brevirostris

2007-07-08T16:50:44Z

68.3.53.1:

{{Taxobox
| color = pink
| name = Lemon shark
| status = LR/nt
| trend = unknown
| image = Lemon shark.png
| image_width = 200px
| regnum = [[Animal]]ia
| phylum = [[Chordata]]
| classis = [[Chondrichthyes]]
| subclassis = [[Elasmobranchii]]
| ordo = [[Carcharhiniformes]]
| familia = [[Carcharhinidae]]
| genus = ''[[Negaprion]]''
| species = '''''N. brevirostris'''''
| binomial = ''Negaprion brevirostris''
| binomial_authority = ([[Felipe Poey|Poey]], [[1868]])
}}
{{Sharksportal}}

The '''lemon shark''', ''Negaprion brevirostris'', is a well studied [[shark]] belonging to the family [[Carcharhinidae]].

==Distribution and habitat==
It is found mainly along the [[subtropical]] and [[tropical]] parts of the [[Atlantic Ocean|Atlantic]] coast of [[North America|North]] and [[South America]]. This species can be found as well in Pacific islands of Polynesia - French Polynesia - Tahiti, Cook Islands, Tongas.

==Reproduction==
Lemon sharks are [[viviparous]], females giving birth to between 4 and 17 young every other year in warm and shallow lagoons. The young have to fend for themselves and remain in shallow water near [[mangrove]]s until they grow larger. With increasing size, the sharks venture further away from their birth place. At maturity at a size of 1.5 to 2 [[metre|m]] and an age of 12 to 15 years, they leave shallow water and move into deeper waters offshore. However, little is known of this life stage. Maximum recorded length and weight is 340 [[centimetre|cm]] and 183 [[kilogram|kg]].[http://fishbase.sinica.edu.tw/summary/SpeciesSummary.php?id=897]

Recent work in [[genetics]] by Drs Kevin Feldheim, Sonny Gruber and Mary Ashley may suggest that adult sharks move over hundreds of [[kilometre|km]] to mate, or populations far apart may have been separated in recent time. Further research in this area would be of immense importance for the understanding of the lemon shark's breeding behaviour and ecology.

==Importance to humans==
[[Image:ZitronenhaiWorld.png|thumb|left|200px|Range of ''N. brevirostris'']]
Lemon sharks are a popular choice for study by scientists as they survive well in captivity, unlike many other species such as [[Great White Shark|great white sharks]], which die in captivity because they refuse food. The species is the best known of all sharks in terms of behaviour and [[ecology]], mainly thanks to the enormous effort of Dr. Samuel Gruber at the [[University of Miami]] who has been studying the lemon shark both in the field and in the laboratory for the past 40 years. The population around [[Bimini Islands]] in the western [[Bahamas]], where Dr Gruber's field station Bimini Biological Field Station is situated, is probably the best known of all shark populations. It is currently experiencing a severe population decline and may disappear altogether due to destruction of the mangroves for construction of a golf [[resort]].

==See also==
* [[List of sharks]]

==References==
* {{IUCN2006|assessors=Gruber & Sundström|year=2000|id=39380|title=Negaprion brevirostris|downloaded=11 May 2006}} Database entry includes justification for why this species is near threatened
* {{ITIS|ID=160433|taxon=Negaprion brevirostris|year=2006|date=23 January}}
* {{FishBase_species|genus=Negaprion|species=brevirostris|year=2005|month=March}}
* ''Washington Post'', 2005, Aug. 22nd: "Scientists Fear Oceans on the Cusp Of a Wave of Marine Extinctions"

==External links==
{{commons|Negaprion brevirostris|Lemon shark}}
* [http://www.sharkdiving.us/lemonshark.html Lemon shark facts and pictures]

[[Category:Sharks]]
[[Category:Viviparous fish]]
[[Category:Carcharhinidae]]

[[cs:Žralok citrónový]]
[[de:Zitronenhai]]
[[fr:Requin citron]]
[[nl:Citroenhaai]]
[[sk:Žralok citrónový]]
[[fi:Sitruunahai]]
[[sv:Citronhaj]]