Leukocyte extravasation

Leukocyte extravasation, less commonly called diapedesis, is the movement of leukocytes out of the circulatory system and towards the site of tissue damage or infection. This process forms part of the innate immune response, involving the recruitment of non-specific leukocytes. Monocytes also use this process in the absence of infection or tissue damage during their development into macrophages.

Overview

Leukocyte extravasation occurs mainly in post-capillary venules, where haemodynamic shear forces are minimised. This process can be understood in several steps, outlined below as "chemoattraction", "rolling adhesion", "tight adhesion" and "(endothelial) transmigration". It has been demonstrated that leukocyte recruitment is halted whenever any of these steps is suppressed.

White blood cells (leukocytes) perform most of their functions in tissues. Functions include phagocytosis of foreign particles, production of antibodies, secretion of inflammatory response triggers (histamine and heparin), and neutralization of histamine. In general, leukocytes are involved in the defense of an organism and protect it from disease by promoting or inhibiting inflammatory responses. Leukocytes use the blood as a transport medium to reach the tissues of the body. Here is a brief summary of each of the four steps currently thought to be involved in leukocyte extravasation:

Rolling (video game)

Rolling is an extreme sports video game released in 2003 for PlayStation 2 and Xbox. Subsequent Game Boy Advance and Gamecube versions were cancelled due to a declining interest in extreme sports titles. To date, it is one of the few other games depicting aggressive inline skating apart from Aggressive Inline and the Jet Set Radio series. It was originally developed by the now defunct Rage Software, who were aiming to create a more authentic recreation of the sport (the box art claims the game features 250 tricks), unlike Aggressive Inline which focused on exaggerated, fantasy-themed levels and high scoring, fairly unrealistic tricks.

Players can choose to skate as one of the twenty available skaters (excluding the twenty first, and hidden, skater) and work their way through a progressively difficult "career mode" featuring a total of fourteen levels, gaining reputation, sponsorship deals, as well as unlocking new 'tricks' and videos of the pro skaters.

Development

Rage Software announced the game just prior to the May 2001 E3 show, with the working title of Cesar and Fabiola's Inline Skate. Rage continued with development of the game throughout 2002, releasing more previews and screenshots of the game as it came to fruition under the new title of Rolling (Sk8). However, Rage Software began to suffer financial problems that year, and were forced to close in January 2003, before the game was released.

Rolling (finance)

Rolling a contract is an investment concept meaning trading out of a standard contract and then buying the contract with next longest maturity, so as to maintain a position with constant maturity.

Motivation

One may roll a contract because one has a special preference for a specific maturity—for example, the five-year CDS rate of a given name—or because a given on-the-run security is more liquid than off-the-run securities.

Examples

While holding US Treasuries, one may wish to hold only the most recently issued security of a given maturity, the so-called on-the-run security. Thus, if one has purchased the on-the-run 30-year treasury and a new 30-year auction occurs, one may sell the old treasury, which is now off-the-run, and purchase the new on-the-run treasury.

For contracts whose maturity falls on the quarterly IMM dates, there is generally very high trading activity on these dates as contracts are rolled.

Index roll congestion

When an index has a published policy for rolling its contracts, such as on a given day or over a given period, a trading strategy is to roll in advance of the index, in anticipation of its trading volume. This is referred to as index roll congestion or, pejoratively, "date rape".

Thunder

Thunder is the sound caused by lightning. Depending on the distance and nature of the lightning, thunder can range from a sharp, loud crack to a long, low rumble (brontide). The sudden increase in pressure and temperature from lightning produces rapid expansion of the air surrounding and within a bolt of lightning. In turn, this expansion of air creates a sonic shock wave, similar to a sonic boom, which produces the sound of thunder, often referred to as a clap, crack, or peal of thunder.

Cause

The cause of thunder has been the subject of centuries of speculation and scientific inquiry. The first recorded theory is attributed to the Greek philosopher Aristotle in the fourth century BC, and an early speculation was that it was caused by the collision of clouds. Subsequently, numerous other theories were proposed. By the mid-19th century, the accepted theory was that lightning produced a vacuum.

In the 20th century a consensus evolved that thunder must begin with a shock wave in the air due to the sudden thermal expansion of the plasma in the lightning channel. The temperature inside the lightning channel, measured by spectral analysis, varies during its 50 μs existence, rising sharply from an initial temperature of about 20,000 K to about 30,000 K, then dropping away gradually to about 10,000 K. The average is about 20,400 K (20,100 °C; 36,300 °F). This heating causes a rapid outward expansion, impacting the surrounding cooler air at a speed faster than sound would otherwise travel. The resultant outward-moving pulse is a shock wave, similar in principle to the shock wave formed by an explosion, or at the front of a supersonic aircraft.

Thunder (Andy Taylor album)

Thunder is the first solo album by British guitarist Andy Taylor, released in 1987. It features former Sex Pistols guitarist Steve Jones on guitar. Jones also co-wrote most of the songs on the album.

The album went out of print in 1990, but would reemerge in a newly expanded version on online music services like iTunes when Taylor made his entire catalog available in 2010. In addition to the original version of Thunder, Taylor's previous solo singles such as "Take It Easy" were included as well.

Track listing

Personnel

Thunder (Jessie J song)

"Thunder" is a song by English recording artist Jessie J. It was written by Jessie J, Claude Kelly, Benjamin Levin, Tor Erik Hermansen and Mikkel Storleer Eriksen for her second studio album Alive (2013), while production was helmed by StarGate and Benny Blanco.

Background

"Thunder" was written by Jessie J, Mikkel S. Eriksen, Tor Erik Hermansen, Claude Kelly and Benny Blanco. It was produced by Eriksen and Hermansen, credited under their production name StarGate, along with Blanco. Jessie's vocals were recorded by Chris Sclafani, Joel Peters, and Justin Pancionendon, with Mark "Exit" Goodchild serving as its engineer. Kelly provided additional vocals on the song. "Thunder" was mixed by Phil Tan and assistants Daniela Rivera and Phil Seaford. Eriksen and Hermansen recorded the song's instrumentation, and Tim Blacksmith and Danny D. were assigned as its executive producers. Andrew "McMuffin" Luftman and Scott "Yarmov" Yarmovsky were credited as production coordinators on the song.

Dice

Dice (singular die or dice; from Old French dé; from Latin datum "something which is given or played";) are small throwable objects with multiple resting positions, used for generating random numbers. Dice are suitable as gambling devices for games like craps and are also used in non-gambling tabletop games.

A traditional die is a rounded cube, with each of its six faces showing a different number of dots (pips) from 1 to 6. When thrown or rolled, the die comes to rest showing on its upper surface a random integer from one to six, each value being equally likely. A variety of similar devices are also described as dice; such specialized dice may have polyhedral or irregular shapes and may have faces marked with symbols instead of numbers. They may be used to produce results other than one through six. Loaded and crooked dice are designed to favor some results over others for purposes of cheating or amusement.

A dice tray, a tray used to contain thrown dice, is sometimes used for gambling or board games, in particular to allow dice throws which do not interfere with other game pieces.