Embryo

An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of fertilization through sexual reproduction until birth, hatching, or germination.

In humans, an embryo is generally considered to be between the first and the eighth week of development after fertilization, and from then it is instead called a fetus. While most organ systems develop from the third week to the eighth, embryonic life begins at conception.

The development of the embryo is called embryogenesis. In organisms that reproduce sexually, once a sperm fertilizes an egg cell, the result is a cell called the zygote, which possesses half the DNA of each of its two parents. In plants, animals, and some protists, the zygote will begin to divide by mitosis to produce a multicellular organism. The result of this process is an embryo.

Etymology

First attested in English in the mid-14c., the word embryon derives from Medieval Latin embryo, itself from Greek ἔμβρυον (embruon), lit. "young one", which is the neuter of ἔμβρυος (embruos), lit. "growing in", from ἐν (en), "in" and βρύω (bruō), "swell, be full"; the proper Latinized form of the Greek term would be embryum.

Pink Floyd bootleg recordings

Pink Floyd bootleg recordings are the collections of audio and video recordings of musical performances by the British rock band Pink Floyd, which were never officially released by the band. The recordings consist of both live performances and outtakes from studio sessions unavailable in official releases. In some cases, certain bootleg recordings may be highly prized among collectors, as at least 40 songs composed by Pink Floyd have never been officially released.

During the 1970s, bands such as Pink Floyd created a lucrative market for the mass production of unofficial recordings with large followings of fans willing to purchase them. In addition, the huge crowds that turned up to these concerts made the effective policing of the audience for the presence of recording equipment virtually impossible. Vast numbers of recordings were issued for profit by bootleg labels.

Some Pink Floyd bootlegs exist in several variations with differing sound quality and length because sometimes listeners have recorded different versions of the same performance at the same time. Pink Floyd was a group that protected its sonic performance, making recording with amateur recording devices difficult. In their career, Pink Floyd played over 1,300 concerts, of which more than 350 were released as bootlegged recordings (sometimes in various versions). Few concerts have ever been broadcast (or repeated once they were broadcast on television), especially during 'the golden age' of the group from 1966 to 1981.

Embryo (1976 film)

Embryo is a 1976 science fiction horror film directed by Ralph Nelson and starring Rock Hudson alongside Barbara Carrera, with a cameo appearance by Roddy McDowall. It deals with the mental and physical consequences of growing a human embryo in an artificial uterus.

Plot

Dr. Paul Holliston (Hudson) is a geneticist who has been living alone in his rambling clinic, which he operates out of his home, after losing his wife in a car crash. This leads to his feeling constant pangs of guilt from his sister-in-law Martha Douglas (Diane Ladd), who has become his assistant.

One night, Holliston runs over a pregnant doberman dog. The dog is fatally injured, but Holliston manages to save one of her unborn puppies by gestating it in an artificial uterus. Because the device still requires nutrients to be supplied by the mother, he must drastically shorten the gestation period: to this end, he uses an experimental growth hormone made from human placental lactogen, which speeds up the embryo's growth.

Opal

Opal is a hydrated amorphous form of silica (SiO₂·nH₂O); its water content may range from 3 to 21% by weight, but is usually between 6 and 10%. Because of its amorphous character, it is classed as a mineraloid, unlike crystalline forms of silica, which are classed as minerals. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, marl, and basalt. Opal is the national gemstone of Australia.

The internal structure of precious opal makes it diffract light; depending on the conditions in which it formed, it can take on many colors. Precious opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. Of these hues, the black opals are the most rare, whereas white and greens are the most common. It varies in optical density from opaque to semitransparent.

Precious opal

Precious opal shows a variable interplay of internal colors, and though it is a mineraloid, it has an internal structure. At microscopic scales, precious opal is composed of silica spheres some 150 to 300 nm in diameter in a hexagonal or cubic close-packed lattice. It was shown by J. V. Sanders in the mid-1960s, that these ordered silica spheres produce the internal colors by causing the interference and diffraction of light passing through the microstructure of the opal. The regularity of the sizes and the packing of these spheres determines the quality of precious opal. Where the distance between the regularly packed planes of spheres is around half the wavelength of a component of visible light, the light of that wavelength may be subject to diffraction from the grating created by the stacked planes. The colors that are observed are determined by the spacing between the planes and the orientation of planes with respect to the incident light. The process can be described by Bragg's law of diffraction.

Opal (armoured personnel carrier)

The Opal-I is a multi-purpose fully amphibious armoured personnel carrier developed and produced by HSW S.A.. APC is a development of MT-LB that was produced in HSW on licence. Major changes are with reworked nose section and propellers for better in water speed and manoeuvrability, new turret with 12.7 mm NSVT machine-gun instead of old with 7.62 PKT and powered-up engine. Opal-II is a stretched variant with longer chassis with 7 road wheels on each side, like the 2S1 and MT-LBu and 300 hp (220 kW) SW680T engine.

Variants

WPT Mors

(WPT for Wóz Pogotowia Technicznego - lit Technical Support Vehicle) - technical support vehicle with light crane, hydraulic dozerblade, welding equipment and an NBC detection system. The vehicle is a basic support vehicle of mechanized battalions equipped with BMP-1 IFV in Polish Land Forces.

TRI Hors

(TRI for Transporter Rozpoznania Inżynieryjnego - lit. Engineering Reconnaissance Vehicle) - engineering vehicle with basic equipment. In use with Polish Land Forces.

List of recurring The Simpsons characters

The Simpsons includes a large array of supporting characters: co-workers, teachers, family friends, extended relatives, townspeople, local celebrities, fictional characters within the show, and even animals. The writers originally intended many of these characters as one-time jokes or for fulfilling needed functions in the town. A number of them have gained expanded roles and have subsequently starred in their own episodes. According to the creator of The Simpsons, Matt Groening, the show adopted the concept of a large supporting cast from the Canadian sketch comedy show Second City Television.

Agnes Skinner

Agnes Skinner (voiced by Tress MacNeille) is the mother of Principal Skinner and first appeared in the first season episode "The Crepes of Wrath" as an old woman who embarrassingly calls her son "Spanky". However, as episodes progressed, the character turned bitter. She is very controlling of her son and often treats him as if he is a child. She hates Edna Krabappel due to her son's feelings for the other woman. Agnes has married four times. Several Springfield residents (including the Simpsons) are afraid of her. When "the real Seymour Skinner" arrives in Springfield, Agnes ends up rejecting him in part because he stands up to her, but also because unlike Skinner/Tamzarian, her biological son is independent and doesn't need her anymore, while Skinner immediately reverts to a good-for-nothing without her.