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 (metalworking)

In metalworking, rolling is a metal forming process in which metal stock is passed through one or more pairs of rolls to reduce the thickness and to make the thickness uniform. The concept is similar to the rolling of dough. Rolling is classified according to the temperature of the metal rolled. If the temperature of the metal is above its recrystallization temperature, then the process is known as hot rolling. If the temperature of the metal is below its recrystallization temperature, the process is known as cold rolling. In terms of usage, hot rolling processes more tonnage than any other manufacturing process, and cold rolling processes the most tonnage out of all cold working processes.Roll stands holding pairs of rolls are grouped together into rolling mills that can quickly process metal, typically steel, into products such as structural steel (I-beams, angle stock, channel stock, and so on), bar stock, and rails. Most steel mills have rolling mill divisions that convert the semi-finished casting products into finished products.

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.

The Times

The Times is a British daily national newspaper based in London. It began in 1785 under the title The Daily Universal Register and became The Times on 1 January 1788. The Times and its sister paper The Sunday Times (founded in 1821) are published by Times Newspapers, since 1981 a subsidiary of News UK, itself wholly owned by the News Corp group headed by Rupert Murdoch. The Times and The Sunday Times do not share editorial staff, were founded independently and have only had common ownership since 1967.

In 1959, historian of journalism Allan Nevins analysed the importance of The Times in shaping the views of events of London's elite:

The Times is the first newspaper to have borne that name, lending it to numerous other papers around the world, including The Times of India (founded in 1838), The Straits Times (Singapore) (1845), The New York Times (1851), The Irish Times (1859), Le Temps (France) (1861-1942), the Cape Times (South Africa) (1872), the Los Angeles Times (1881), The Seattle Times (1891), The Manila Times (1898), The Daily Times (Malawi) (1900), El Tiempo (Colombia) (1911), The Canberra Times (1926), and The Times (Malta) (1935). In these countries, the newspaper is often referred to as The London Times or The Times of London.

Times New Roman

Times New Roman is a serif typeface commissioned by the British newspaper The Times in 1931 and created by Victor Lardent in collaboration with the British branch of the printing equipment company Monotype. Although no longer used by The Times, Times New Roman is still very common in book and general printing. Through distribution with Microsoft products and as a standard computer font, it has become one of the most widely used typefaces in history.

Times New Roman's creation took place through the influence of Stanley Morison of Monotype. Morison was an artistic director at Monotype, historian of printing and informal adviser to the Times, who recommended that they change typeface from the spindly and somewhat dated nineteenth-century Didone typeface previously used to a more robust, solid design, returning to traditions of printing from the eighteenth century and before. This matched a common trend in printing of the period.

Morison proposed an older Monotype typeface named Plantin as a basis for the design, but revisions were made to increase legibility and economy of space. The new font was drawn by Victor Lardent, an artist from the advertising department of The Times, with Morison consulting, before refinement by the experienced Monotype drawing office team.The new design made its debut in the 3 October 1932 issue of The Times. After one year, the design was released for commercial sale. The Times stayed with Times New Roman for 40 years, but new production techniques and the format change from broadsheet to tabloid in 2004 have caused the newspaper to switch typeface five times since 1972. However, all the new fonts have been variants of the original New Roman typeface.

Multiplication sign

The multiplication sign or times sign is the symbol ×. The symbol is similar to the lowercase letter x but is a more symmetric saltire, and has different uses. It is also known as St. Andrew's Cross and dimension sign.

Uses

In mathematics, the symbol × (read as times or multiplied by) is primarily used to denote the

In biology, the multiplication sign is used in a botanical hybrid name, where it is read as "cross".

The multiplication sign is also used by historians for an event between two dates. When employed between two dates, for example 1225 and 1232, 1225×1232 means "no earlier than 1225 and no later than 1232". It can also be used in a date range: 1225×1232–1278.

History

The × symbol for multiplication was introduced by William Oughtred in 1631. It was chosen for religious reasons to represent the cross.