Phagocytes are cells that protect the body by ingesting harmful foreign particles, bacteria, and dead or dying cells. Their name comes from the Greek phagein, "to eat" or "devour", and "-cyte", the suffix in biology denoting "cell", from the Greek kutos, "hollow vessel". They are essential for fighting infections and for subsequent immunity. Phagocytes are important throughout the animal kingdom and are highly developed within vertebrates. One litre of human blood contains about six billion phagocytes. They were discovered in 1882 by Ilya Ilyich Mechnikov while he was studying starfish larvae. Mechnikov was awarded the 1908 Nobel Prize in Physiology or Medicine for his discovery. Phagocytes occur in many species; some amoebae behave like macrophage phagocytes, which suggests that phagocytes appeared early in the evolution of life.Phagocytes of humans and other animals are called "professional" or "non-professional" depending on how effective they are at phagocytosis. The professional phagocytes include many types of white blood cells (such as...

The uppermost portion of the Sun's atmosphere is called the corona.

Netball is a ball sport played on a court by two teams of seven players. It is among a rare number of sports which have been created exclusively for female competitors. The sport is played on indoor and outdoor netball courts and is specifically played in schools. Netball is most popularly played in Commonwealth nations. A common misunderstanding of the sport's origins has resulted in the mistaken belief that netball was created to prevent women from playing basketball. However, the sport is the result of Clara Baer's misinterpretation of its rules. Baer had asked James Naismith, the inventor of basketball, to send her a copy of the rules, and Baer's errors resulted in what marked the beginning of the development of a separate sport. Netball originated in England, in the late 19th century. In the beginning it was described as 'women's basketball' but had emerged as a distinctly separate sport due to its different rules. It was not until the latter half of the 20th century that the name "netball" became the sport's commonly referred name. Netball differs greatly from its 'sister' sport of women's basketball because it bars dribbling...

Ambiguity is the type of meaning in which a phrase, statement or resolution is not explicitly defined, making several interpretations plausible. A common aspect of ambiguity is uncertainty. It is thus an attribute of any idea or statement whose intended meaning cannot be definitively resolved according to a rule or process with a finite number of steps. (The ambi- part of the term reflects an idea of "two", as in "two meanings".) The concept of ambiguity is generally contrasted with vagueness. In ambiguity, specific and distinct interpretations are permitted (although some may not be immediately obvious), whereas with information that is vague, it is difficult to form any interpretation at the desired level of specificity. Linguistic forms Lexical ambiguity is contrasted with semantic ambiguity. The former represents a choice between a finite number of known and meaningful context-dependent interpretations. The latter represents a choice between any number of possible interpretations, none of...

A steam turbine is a machine that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Charles Parsons in 1884. Fabrication of a modern steam turbine involves advanced metalwork to form high-grade steel alloys into precision parts using technologies that first became available in the 20th century; continued advances in durability and efficiency of steam turbines remains central to the energy economics of the 21st century. The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from the use of multiple stages in the expansion of the steam, which results in a closer approach to the ideal reversible expansion process. Because the turbine generates rotary motion, it can be coupled to a generator to harness its motion into electricity. Such turbogenerators are the core of thermal power stations which can be fueled by fossil-fuels, nuclear fuels, geothermal, or solar energy. About 85% of all electricity generation in the United States in the year 2014 was by use of steam turbines.As of 2021, among the largest...

The Japanese Experiment Module (JEM), nicknamed Kibō (きぼう, Kibō, Hope), is a Japanese science module for the International Space Station (ISS) developed by JAXA. It is the largest single ISS module, and is attached to the Harmony module. The first two pieces of the module were launched on Space Shuttle missions STS-123 and STS-124. The third and final components were launched on STS-127. Components In initial configuration, Kibō consisted of six major elements: Pressurized Module (PM) Exposed Facility (EF) Experiment Logistics Module (ELM) Pressurized Section (ELM-PS) Experiment Logistics Module (ELM) Exposed Section (ELM-ES) Japanese Experiment Module remote manipulator system (JEMRMS) Inter-orbit communication system (ICS)Pressurized Module The Pressurized Module (PM) is the core component connected...

The Benin ivory mask is a miniature sculptural portrait in ivory of Idia, the first Iyoba (Queen Mother) of the 16th century Benin Empire, taking the form of a traditional African mask. The masks were looted by the British from the palace of the Oba of Benin in the Benin Expedition of 1897. Two almost identical masks are kept at the British Museum in London and at the Metropolitan Museum of Art in New York City. Both feature a serene face of the Queen Mother wearing a beaded headdress, a beaded choker at her neck, scarification highlighted by iron inlay on the forehead, and all framed by the flange of an openwork tiara and collar of symbolic beings, as well as double loops at each side for attachment of the pendant. There are also examples on the same theme at the Seattle Art Museum and the Linden Museum, and one in a private collection.The British Museum example in particular has also become a cultural emblem of modern Nigeria since FESTAC 77, a major pan-African cultural festival held in Lagos, Nigeria in 1977, which chose as is official emblem a replica of the mask crafted by Erhabor Emokpae....

A fingerprint is an impression left by the friction ridges of a human finger. The recovery of partial fingerprints from a crime scene is an important method of forensic science. Moisture and grease on a finger result in fingerprints on surfaces such...

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