Collision (telecommunications)

A collision is the situation that occurs when two or more demands are made simultaneously on equipment that can handle only one at any given instant. It may refer to:

References

Collision (Heroes)

"Collision" is the fourth episode of the first season of the NBC science fiction drama series Heroes. It was originally titled "Come Together".

Plot

Matt Parkman is a prisoner of Mr. Bennet and the mysterious man. When it is revealed Matt knows of a Claire, the mysterious man is ordered to "clean Matt out", a painful process.

Hiro and Ando arrive in Las Vegas. Ando helps Hiro with the warning messages for Isaac Mendez, so Isaac will know that he and the city of New York are in danger.

They pass by Niki Sanders and her son Micah, who are on their way to meet Mr. Linderman. Instead, they meet one of his associates. With Micah in the other room, Niki is told she will sexually blackmail a politician Linderman is involved with, as a form of 'insurance'.

Claire Bennet's body lies on the autopsy table as the coroner does a V-incision on her chest. Recording the details, the coroner notes that she was found naked and dragged into the Red River Creek. With the coroner distracted by a phone call, Claire heals up sufficiently to steal a lab coat and sneak out.

Collision (TV series)

Collision is a five-part television drama miniseries, which debuted on ITV & UTV in November 2009. In the same month, it was also on PBS as a series in two parts. It tells the story of a group of strangers whose lives intertwine following a devastating car crash. The crash opens a number of startling revelations as stories of everything from government cover-ups and smuggling, to embezzlement and murder start to unravel.

The series is open-ended, with a number of unresolved issues; moreover, the story is ostensibly resolved in a metafictional manner with a flashback to an incident in the service station and the swatting of a wasp, which precipitates the initial crash, thus allowing the characters to carry on on their journeys. The wasp as a motif and theme is frequently in evidence throughout the series.

The original British broadcast of Collision was edited from the original 5 hours (shown in five parts) down to three and a half hours (210 minutes, shown in two parts). The American broadcast on PBS's Masterpiece Contemporary, the Australian broadcast on ABC1 and the Region 1 (America and Canada) DVD release all featured the shortened version. In Australia, Foxtel and Austar's W Channel aired Collision in its original format of five 45-minute episodes (excluding advertisements), Tuesday, 15 March 2011.

Loop (inlet)

The Loop or Darss Canal (Darßer Kanal) was an inlet of the sea between the lagoon known as the Saaler Bodden and the Baltic Sea near Ahrenshoop on the German coast. It formed the northern boundary of the region of Fischland. Originally the Loop was the northern estuarine branch of the River Recknitz.

The old inlet ran between the present villages of Ahrenshoop and Althagen. The Loop was roughly two metres deep and had posts for mooring boats and barges. Its navigability was frequently curtailed by storms and silting up. Today only a small ditch remains on the former Mecklenburg-Pomeranian border, which runs alongside a main road, the so-called Grenzweg ("border way").

The cartographer and court astronomer at the Mecklenburg court, Tilemann Stella, described the Loop thus: "Between the village of Oldenhagen [Althagen] and the Arnshope [Ahrenshoop], the waters of the Ribnitz river and lake break through into the salty sea. Beyond the beach is a large pile of rock and bricks at the place by the beach; that was the customs post, located 3 or 4 ruthen [50 metres] into the salty sea. Beyond that, forty or fifty posts stood in the salt sea, at the end of which was a large pile of rocks on which the fort stood."

Turn (biochemistry)

A turn is an element of secondary structure in proteins where the polypeptide chain reverses its overall direction. For beta turns go to Beta turn.

Definition

According to one definition, a turn is a structural motif where the C^α atoms of two residues separated by few (usually 1 to 5) peptide bonds are close (< 7 Å), while the residues do not form a secondary structure element such as an alpha helix or beta sheet with regularly repeating backbone dihedral angles. Although the proximity of the terminal C^α atoms usually correlates with formation of a hydrogen bond between the corresponding residues, a hydrogen bond is not a requirement in this turn definition. That said, in many cases the H-bonding and C^α-distance definitions are equivalent.

Types of turns

Turns are classified according to the separation between the two end residues:

In an α-turn the end residues are separated by four peptide bonds ().

In a β-turn (the most common form), by three bonds ().

In a γ-turn, by two bonds ().

Loopback

Loopback, or loop-back, refers to the routing of electronic signals, digital data streams, or flows of items back to their source without intentional processing or modification. This is primarily a means of testing the transmission or transportation infrastructure.

Many example applications exist. It may be a communication channel with only one communication endpoint. Any message transmitted by such a channel is immediately and only received by that same channel. In telecommunications, loopback devices perform transmission tests of access lines from the serving switching center, which usually does not require the assistance of personnel at the served terminal. Loop around is a method of testing between stations that are not necessarily adjacent, where in two lines are used, with the test being done at one station and the two lines are interconnected at the distant station. A patch cable may also function as loopback, when applied manually or automatically, remotely or locally, facilitating a loop-back test.