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=== Draft of the Week <font size=1>[ [[CZ:Article of the Week|about]] ]</font> ===
=== Draft of the Week <font size=1>[ [[CZ:Article of the Week|about]] ]</font> ===
[[Image:Showy lady slipper.jpg|thumb|right|200px]]
[[Image:Japaneseinternment.jpg|An internment camp in California {{photo|Ansel Adams}}|right|thumb]]
There are tens of thousands of [[species]], [[cultivar]]s and varieties in the '''[[orchid]]''' family, the largest family of flowering plants.  The word ''orchid'' may refer to any of the botanical family Orchidaceae, or, more often among lay persons, any of thousands of [[flower]]s called "orchids".
'''[[Korematsu v. United States]]''' was one of four [[Supreme Court of the United States|United States Supreme Court]] cases that dealt with the constitutionality of the [[Japanese internment]] during [[World War II]]. In its December 18, 1944 decision to uphold the internment, the Court argued forcefully that military necessity legitimates expansive federal government war powers, including those that curtail the civil liberties of specific racial groups.


Orchids have been cultivated for centuries.  They include rare and recent discoveries such as the tiny ''[[Tallong Midge Orchid|Genoplesium plumosum]]'', the large, showy orchids which are featured in bouquets and corsages, and 'food' orchids such as ''[[Vanilla]]''. A few orchids have insignificant flowers but are grown for their [[leaf|foliage]].  Most orchids are [[epiphyte]] plants; they do not root in soil, and must gain all their water and nutrients from the air and rain. Orchids have evolved to make optimal use of these scarce resources. Some keep water in thickened, almost succulent stems, called pseudobulbs, others have highly porous roots covered by a spongy layer, that can absorb humidity from the air; other store water in thick leaves; and other terrestrial orchids in small root tubers. Some species go through long periods of rest when their [[metabolism]] is reduced, followed by a fast [[growth]], blooming when resources are abundant. Many species lose their leaves to avoid [[dehydration ]] during droughts, or while they are resting.
The December 7, 1941 attack by [[Japan]] on [[Pearl Harbor]] prompted widespread concern about the security of the United States' West Coast and the possibility of espionage by members of its large Japanese-American population. On February 19, 1942, President [[Franklin D. Roosevelt]] responded by issuing [[Executive Order]] (EO) 9066, which authorized the Secretary of War and his designated commanders to establish "military areas" as they see fit and exclude "any or all persons" from entering or remaining within them. The main result of Roosevelt's order was the relocation of more than 100,000 Americans of [[Japanese]] descent from the West Coast into [[internment camp]]s in the interior of the United States. A month later, [[U.S._Congress|Congress]] passed Public Law 503, which criminalized violations of military orders issued as a result of EO 9066.
<font size=1>[[Orchid|['''more...''']]]</font>
 
Persuant to EO 9066, on May 3, 1942, the U.S. army issued Civilian Exclusion Order Number 34, which instructed all persons of Japanese ancestry living in San Leandro, California to evacuate the area by the end of that week. Fred Korematsu, a California-born American citizen whose parents had emigrated from Japan in 1905, refused to comply with the exclusion order.
<font size=1>[[Korematsu v. United States|['''more...''']]]</font>


=== New Draft of the Week <font size=1>[ [[CZ:New Draft of the Week|about]] ]</font> ===
=== New Draft of the Week <font size=1>[ [[CZ:New Draft of the Week|about]] ]</font> ===
{{Image|Adipocyte.png|right|250px|}}
'''[[Vector rotation]]s''' are widely used not only in the sciences, such as [[physics]], [[chemistry]] and [[mathematics]], but are critical for graphics computations in [[computer game]] programs and navigation in spaceA typical example used in computer games would be calculating the graphics for a military tank rolling up a slanted hill, the relative rotation of the tank's turret, and the elevation of the tanks' barrel.  Although a rotation matrix for each point of the tank ''could'' be calculated individually, a more economical method is to calculate a single rotation matrix for the entire tank and apply that solution to every current position of the tank as it rolls up the hill. Additional rotations are then used for the turret rotation by a second multiplication.
A major breakthrough in the study of appetite regulation came in 1994 when the molecular geneticist Jeffrey Friedman discovered the adiposity signal '''[[leptin]]'''.  By studies of an inbred line of obese mice, the ''ob/ob'' mice which were thought to lack a satiety signal, Friedman and colleagues found that 'ob' codes for a gene that coded for a novel peptide hormone, which they called ''leptin'', from the Greek ‘leptos’ meaning thin. Mice deficient in this gene are morbidly obese and this obesity can be reversed by giving the mice leptin.
 
The leptin receptor was found in 1995 and is a member of the [[cytokine]] receptor family.


Leptin is a signaling molecule secreted from [[adipocyte]] cells into the blood, and the plasma concentration of leptin is thus proportional to the total body fat mass. Leptin is transported into the brain from the blood, where it suppresses apetite by its effects on specific neurones in the brain that express leptin receptors; in particular on neurons of the [[arcuate nucleus]] and [[ventromedial nucleus]] of the [[hypothalamus]]. Leptin receptor mRNA is found primarily in the hypothalamic arcuate nucleus, ventromedial nuclei and dorsomedial hypothalamic nuclei, regions that are known to be involved in appetite control. <font size=1>[[Leptin|['''more...''']]]</font>  
A variety of methods can be used to determine the rotation matrix (in 3D or 4D space) needed to convert vector V<sub>1</sub> into vector V<sub>2</sub>. Because they provide non-unique results, inverse trigonometry functions should only be used with great caution.  [[Quaternions]], a 4-dimensional approach in 3D space, can also be used, and this method has devoted followers and critics. Although several 3D matrix rotation methods can be used, the method of Hughes (J. Graphics Tools, 2000) is particularly fast, because it avoids time-consuming inverse trigonometry and square root calculations, and avoids computational pitfalls of instability inherent to some of the previous methods. <font size=1>[[Vector rotation|['''more...''']]]</font>  
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Draft of the Week [ about ]

An internment camp in California Template:Photo

Korematsu v. United States was one of four United States Supreme Court cases that dealt with the constitutionality of the Japanese internment during World War II. In its December 18, 1944 decision to uphold the internment, the Court argued forcefully that military necessity legitimates expansive federal government war powers, including those that curtail the civil liberties of specific racial groups.

The December 7, 1941 attack by Japan on Pearl Harbor prompted widespread concern about the security of the United States' West Coast and the possibility of espionage by members of its large Japanese-American population. On February 19, 1942, President Franklin D. Roosevelt responded by issuing Executive Order (EO) 9066, which authorized the Secretary of War and his designated commanders to establish "military areas" as they see fit and exclude "any or all persons" from entering or remaining within them. The main result of Roosevelt's order was the relocation of more than 100,000 Americans of Japanese descent from the West Coast into internment camps in the interior of the United States. A month later, Congress passed Public Law 503, which criminalized violations of military orders issued as a result of EO 9066.

Persuant to EO 9066, on May 3, 1942, the U.S. army issued Civilian Exclusion Order Number 34, which instructed all persons of Japanese ancestry living in San Leandro, California to evacuate the area by the end of that week. Fred Korematsu, a California-born American citizen whose parents had emigrated from Japan in 1905, refused to comply with the exclusion order. [more...]

New Draft of the Week [ about ]

Vector rotations are widely used not only in the sciences, such as physics, chemistry and mathematics, but are critical for graphics computations in computer game programs and navigation in space. A typical example used in computer games would be calculating the graphics for a military tank rolling up a slanted hill, the relative rotation of the tank's turret, and the elevation of the tanks' barrel. Although a rotation matrix for each point of the tank could be calculated individually, a more economical method is to calculate a single rotation matrix for the entire tank and apply that solution to every current position of the tank as it rolls up the hill. Additional rotations are then used for the turret rotation by a second multiplication.

A variety of methods can be used to determine the rotation matrix (in 3D or 4D space) needed to convert vector V1 into vector V2. Because they provide non-unique results, inverse trigonometry functions should only be used with great caution. Quaternions, a 4-dimensional approach in 3D space, can also be used, and this method has devoted followers and critics. Although several 3D matrix rotation methods can be used, the method of Hughes (J. Graphics Tools, 2000) is particularly fast, because it avoids time-consuming inverse trigonometry and square root calculations, and avoids computational pitfalls of instability inherent to some of the previous methods. [more...]