Loop (knot)

In reference to knots, loop may refer to:

References

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.

Medway (Mount Holly, South Carolina)

Medway or the Medway Plantation is a plantation in Mount Holly, South Carolina within Berkeley County, South Carolina. It is about 2 mi (3.2 km) east of U.S. Route 52 from the unincorporated community of Mount Holly, which is directly north of Goose Creek, South Carolina. It was named to the National Register of Historic Places on July 16, 1970.

History

Jan Van Arrsens, the Seigneur of Wernhaut (also "Weirnhoudt"), led a small group of settlers from Holland to the province of Carolina around 1686. He built his house on the Back River, which was formerly called the "Meadway" or "Medway" and is a tributary of the Cooper River. Van Arrsens died soon after his arrival and was buried at Medway.

His widow, Sabrina de Vignon, married Landgrave Thomas Smith around 1687, which made Smith one of the wealthiest men in the Province. Sabrina Smith died in 1689 and was buried at Medway. Thomas Smith was appointed governor of the Province of Carolina in 1693. He died in 1694 and was also buried at Medway.