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=== Article of the Week <font size=1>[ [[CZ:Article of the Week|about]] ]</font> ===
=== Article of the Week <font size=1>[ [[CZ:Article of the Week|about]] ]</font> ===
The '''[[Ether (physics)|ether]]''' (also spelled '''aether''') was a concept in [[physics]] made obsolete in 1905 by [[Albert Einstein|Einstein]]'s theory of [[special relativity]].  
A month-long action fought in the [[Vietnam War]] in 1965, the '''[[Battle of the Ia Drang]]''' was a campaign, with two major battles against the a [[division (military)|division]]-sized force from the [[People's Army of Viet Nam]] ([[PAVN]]), although the first U.S. battle is better known in the West.  It is an especially informative topic, since, in addition to the U.S. reports that long have been available, some of the key commanders on both the North Vietnamese and U.S. sides have met as friends, and discussed the different perspectives. South Vietnamese reporting is also available.


The idea of an ether was introduced into science by [[René Descartes|Descartes]] in [[Principles of Philosophy|Principia philosophiae]] (1644). Until that time, forces between two bodies that are not in direct contact were assumed to act through space&mdash;by [[action at a distance]]. Descartes  replaced this explanation by one based on an intermediate medium (ether) consisting of vortices that transmit forces between bodies at a distance.
The engagement took place in the South Vietnamese [[II Corps tactical zone]] area, headed by MG [[Vinh Loc]].  
 
<font size=1>[[Battle of the Ia Drang|['''more...''']]]</font>
The ether concept became especially predominant in the 19th century by the work of [[Thomas Young|Young]] and [[Augustin-Jean Fresnel|Fresnel]] who revived [[Christiaan Huygens|Huygens]]' wave theory of light.  They replaced [[Newton]]'s light corpuscles by waves propagating through the ether. In order to explain [[stellar aberration]], first observed in the 1720s and then shown to be caused by the velocity of the earth relative to the velocity of Newton's light corpuscles, Young (1804) assumed ether to be in a state of absolute rest.  [[James Clerk Maxwell|Maxwell]]  showed in the 1860s that light waves are [[electromagnetic wave]]s  transverse (perpendicular) to the direction of the propagation  of the waves. Following Young and Fresnel,  Maxwell assumed that electromagnetic waves are vibrations of the ether.   
<font size=1>[[Ether (physics)|['''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> ===
In computer and network security, a '''[[Worm (computers)|worm]]''' is a form of [[malware]] that, once it activates inside a victim's computer, can replicate and propagate itself without further user activity. Worms often take up valuable memory and network bandwidth, which can cause a computer to stop responding, and can also allow attackers to gain unauthorized remote control of one or more computers.  
{{Image|Leptotes bicolor.jpg|right|150px|Leptotes bicolor}}
'''''[[Leptotes]]''''' is a genus of [[orchid]]s formed by nine small species that grow in the dry jungles of south and southeast [[Brazil]], and also in [[Paraguay]] or [[Argentina]]. They are small [[epiphytic]] plants of [[caespitific]] growth, that sometimes resemble little ''[[Brassavola]]'', as they share the same type of thin terete leaves, however, they are more closely related to ''[[Loefgrenianthus]]''.


While the idea of a parasitic worm goes far back in biology, the term appears to have first been used as, as a concept in computing, in [[John Brunner]]'s 1975 science fiction novel, ''[[Shockwave Rider]]''.  Actual software, under tightly controlled conditions, was developed in 1981-1982. <font size=1>[[Worm (computers)|['''more...''']]]</font>  
Some species of ''Leptotes'' are widely cultivated and form showy displays when completely in bloom although they are not among the easiest to grow. The majority of the species are not cultivated and some are so rare to be almost unknown; five of the species have only recently been described since 2000.  Beside being cultivated for their ornamental value, there are records of the flowers and fruits of ''[[Leptotes bicolor]]'' being used as a substitute for [[vanilla]] in milk, ice cream, tea and candies. <font size=1>[[Leptotes|['''more...''']]]</font>  
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Revision as of 22:04, 3 March 2009


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Article of the Week [ about ]

A month-long action fought in the Vietnam War in 1965, the Battle of the Ia Drang was a campaign, with two major battles against the a division-sized force from the People's Army of Viet Nam (PAVN), although the first U.S. battle is better known in the West. It is an especially informative topic, since, in addition to the U.S. reports that long have been available, some of the key commanders on both the North Vietnamese and U.S. sides have met as friends, and discussed the different perspectives. South Vietnamese reporting is also available.

The engagement took place in the South Vietnamese II Corps tactical zone area, headed by MG Vinh Loc. [more...]

New Draft of the Week [ about ]

(CC) Photo: Dalton Holland Baptista
Leptotes bicolor

Leptotes is a genus of orchids formed by nine small species that grow in the dry jungles of south and southeast Brazil, and also in Paraguay or Argentina. They are small epiphytic plants of caespitific growth, that sometimes resemble little Brassavola, as they share the same type of thin terete leaves, however, they are more closely related to Loefgrenianthus.

Some species of Leptotes are widely cultivated and form showy displays when completely in bloom although they are not among the easiest to grow. The majority of the species are not cultivated and some are so rare to be almost unknown; five of the species have only recently been described since 2000. Beside being cultivated for their ornamental value, there are records of the flowers and fruits of Leptotes bicolor being used as a substitute for vanilla in milk, ice cream, tea and candies. [more...]