Fraxinus

Fraxinus /ˈfræksᵻnəs/, English name ash, is a genus of flowering plants in the olive and lilac family, Oleaceae. It contains 45–65 species of usually medium to large trees, mostly deciduous though a few subtropical species are evergreen. The genus is widespread across much of Europe, Asia and North America.

The tree's common English name, "ash", goes back to the Old English æsc, while the generic name originated in Latin. Both words also mean "spear" in their respective languages. The leaves are opposite (rarely in whorls of three), and mostly pinnately compound, simple in a few species. The seeds, popularly known as "keys" or "helicopter seeds", are a type of fruit known as a samara. Most Fraxinus species are dioecious, having male and female flowers on separate plants; if grown as an ornamental and both sexes are present, ashes can cause a considerable litter problem with their seeds. Rowans or mountain ashes have leaves and buds superficially similar to those of true ashes but belong to the unrelated genus Sorbus in the rose family.

Almquist shell

The Almquist shell (also known as A Shell, ash and sh) is a lightweight Unix shell originally written by Kenneth Almquist in the late 1980s. Initially a clone of the System V.4 variant of the Bourne shell, it replaced the original Bourne shell in the BSD versions of Unix released in the early 1990s. Derivative versions of ash are still installed as the default shell (/bin/sh) on FreeBSD, NetBSD, DragonFly BSD, MINIX, and Android, and in some Linux distributions.

Debian and derived Linux distributions such as Ubuntu ship a version of ash, known as dash (Debian Almquist shell), as the default /bin/sh, although Bash is the default login shell for interactive use. The reason for using dash is faster shell script execution, especially during startup of the operating system, compared to previous versions of Debian and Ubuntu that used Bash for this purpose.

Ash is also fairly popular in embedded Linux systems; its code was incorporated into the BusyBox catch-all executable often employed in this area.

Ash (deity)

Ash was the ancient Egyptian god of oases, as well as the vineyards of the western Nile Delta and thus was viewed as a benign deity. Flinders Petrie in his 1923 expedition to the Saqqara (also spelt Sakkara) found several references to Ash in Old Kingdom wine jar seals: "I am refreshed by this Ash" was a common inscription.

In particular, he was identified by the Ancient Egyptians as the god of the Libu and Tinhu tribes, known as the "people of the oasis". Consequently Ash was known as the "lord of Libya", the western border areas occupied by the Libu and Tinhu tribes, corresponds roughly with the area of modern Libya. It is also possible that he was worshiped in Ombos, as their original chief deity.

In Egyptian mythology, as god of the oases, Ash was associated with Set, who was originally god of the desert, and was seen as protector of the Sahara. The first known reference to Ash dates to the Protodynastic Period, but by the late 2nd Dynasty, his importance had grown, and he was seen as protector of the royal estates, since the related god Set, in Lower Egypt, was regarded as the patron deity of royalty itself. Ash's importance was such that he was mentioned even until the 26th Dynasty.

Volcanic ash

Volcanic ash consists of fragments of pulverized rock, minerals and volcanic glass, created during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products (correctly referred to as tephra), including particles larger than 2mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the escaping gas shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometers away.

Due to its wide dispersal, ash can have a number of impacts on society, including human and animal health, disruption to aviation, disruption to critical infrastructure (e.g., electric power supply systems, telecommunications, water and waste-water networks, transportation), primary industries (e.g., agriculture), buildings and structures.

Tree (Johnny Duhan album)

Tree is an album by Irish folk singer Johnny Duhan.

Track listing

External links

Tree (data structure)

In computer science, a tree is a widely used abstract data type (ADT)--or data structure implementing this ADT--that simulates a hierarchical tree structure, with a root value and subtrees of children with a parent node, represented as a set of linked nodes.

A tree data structure can be defined recursively (locally) as a collection of nodes (starting at a root node), where each node is a data structure consisting of a value, together with a list of references to nodes (the "children"), with the constraints that no reference is duplicated, and none points to the root.

Alternatively, a tree can be defined abstractly as a whole (globally) as an ordered tree, with a value assigned to each node. Both these perspectives are useful: while a tree can be analyzed mathematically as a whole, when actually represented as a data structure it is usually represented and worked with separately by node (rather than as a list of nodes and an adjacency list of edges between nodes, as one may represent a digraph, for instance). For example, looking at a tree as a whole, one can talk about "the parent node" of a given node, but in general as a data structure a given node only contains the list of its children, but does not contain a reference to its parent (if any).

Tree (Gaelic Storm album)

Tree is a 2001 album by Gaelic Storm.

Track listing

Beggarman, Black is the Colour, New York Girl, An Poc Ar Buile, and Go Home Girl are traditionals. Beggarman, which is played fast, is a standard in their live set list and features a didgeridoo very prominently. Black is the Colour, sung by guitarist Steve Twigger, is very slow and mournful, reminiscent of the original composition from the previous album She Was the Prize. An Poc Ar Buile is the band's first venture in the Irish language. The song is normally slowly sung, but Gaelic Storm puts a twist into it by singing it fast, complete with hoots and hollers. Go Home, Girl is a faster tune about a girl who falls in love with a gypsy, only to have her advances turned down for an ironic reason.