In cell biology, the nucleus is a membrane-bound organelle found in eukaryotic cells. Eukaryotes usually have a single nucleus, but a few cell types, such as mammalian red blood cells, have no nuclei, and a few others including osteoclasts have many.
In organic chemistry, functional groups are specific substituents or moieties within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction(s) regardless of the size of the molecule it is a part of. This allows for systematic prediction of chemical reactions and behavior of chemical compounds and design of chemical syntheses. Furthermore, the reactivity of a functional group can be modified by other functional groups nearby. In organic synthesis, functional group interconversion is one of the basic types of transformations.
The true finches are small to medium-sized passerine birds in the family Fringillidae. Finches have stout conical bills adapted for eating seeds and often have colourful plumage. They occupy a great range of habitats where they are usually resident and do not migrate. They have a worldwide distribution except for Australia and the polar regions. The family includes species known as siskins, canaries, redpolls, serins, grosbeaks and euphonias.
A hydroxy or hydroxyl group is the entity with the formula OH. It contains oxygen bonded to hydrogen. In organic chemistry, alcohol and carboxylic acids contain hydroxy groups. The anion [OH−], called hydroxide, consists of a hydroxyl group.
An instrumental is a musical composition or recording without lyrics, or singing, although it might include some inarticulate vocals, such as shouted backup vocals in a Big Band setting. Through semantic widening, a broader sense of the word song may refer to instrumentals. The music is primarily or exclusively produced using musical instruments. An instrumental can exist in music notation, after it is written by a composer; in the mind of the composer ; as a piece that is performed live by a single instrumentalist or a musical ensemble, which could range in components from a duo or trio to a large Big Band, concert band or orchestra.
In chemistry, an organic compound is generally any chemical compound that contains carbon. Due to carbon's ability to catenate, millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprises the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds, along with a handful of other exceptions, are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive.
The Divine Comedy is an Italian long narrative poem by Dante Alighieri, begun c. 1308 and completed in 1320, a year before his death in 1321. It is widely considered to be the preeminent work in Italian literature and one of the greatest works of world literature. The poem's imaginative vision of the afterlife is representative of the medieval world-view as it had developed in the Western Church by the 14th century. It helped establish the Tuscan language, in which it is written, as the standardized Italian language. It is divided into three parts: Inferno, Purgatorio, and Paradiso.
Enriched uranium is a type of uranium in which the percent composition of uranium-235 has been increased through the process of isotope separation. Natural uranium is 99.284% 238U isotope, with 235U only constituting about 0.711% of its mass. 235U is the only nuclide existing in nature that is fissile with thermal neutrons.
A soundtrack, also written sound track, can be recorded music accompanying and synchronized to the images of a motion picture, book, television program, or video game; a commercially released soundtrack album of music as featured in the soundtrack of a film, video, or television presentation; or the physical area of a film that contains the synchronized recorded sound.
Pseudoephedrine (PSE) is a sympathomimetic drug of the phenethylamine and amphetamine chemical classes. It may be used as a nasal/sinus decongestant, as a stimulant, or as a wakefulness-promoting agent in higher doses.
Cannabidiol (CBD) is a phytocannabinoid discovered in 1940. It is one of some 113 identified cannabinoids in cannabis plants and accounts for up to 40% of the plant's extract. In 2018, clinical research on cannabidiol included preliminary studies of anxiety, cognition, movement disorders, and pain.
Grosbeak is a form taxon containing various species of seed-eating passerine birds with large beaks. Although they all belong to the superfamily Passeroidea, these birds are not part of a natural group but rather a polyphyletic assemblage of distantly related songbirds. Some are cardueline finches in the family Fringillidae, while others are cardinals in the family Cardinalidae; one is a member of the weaver family Ploceidae. The word "grosbeak", first applied in the late 1670s, is a partial translation of the French grosbec, where gros means "large" and bec means "beak".
A bakhsh is a type of administrative division of Iran. While sometimes translated as county, it should be more accurately translated as district, similar to a township in the United States or a district of England.
The first level of country subdivisions of Iran are the provinces.
Computer hardware includes the physical, tangible parts or components of a computer, such as the cabinet, central processing unit, monitor, keyboard, computer data storage, graphics card, sound card, speakers and motherboard. By contrast, software is instructions that can be stored and run by hardware. Hardware is so-termed because it is "hard" or rigid with respect to changes or modifications; whereas software is "soft" because it is easy to update or change. Intermediate between software and hardware is "firmware", which is software that is strongly coupled to the particular hardware of a computer system and thus the most difficult to change but also among the most stable with respect to consistency of interface. The progression from levels of "hardness" to "softness" in computer systems parallels a progression of layers of abstraction in computing.
The système universitaire de documentation or SUDOC is a system used by the libraries of French universities and higher education establishments to identify, track and manage the documents in their possession. The catalog, which contains more than 10 million references, allows students and researchers to search for bibliographical and location information in over 3,400 documentation centers. It is maintained by the Bibliographic Agency for Higher Education (ABES).
Tropicos is an online botanical database containing taxonomic information on plants, mainly from the Neotropical ecozone. It is maintained by the Missouri Botanical Garden and was established over 25 years ago. The database contains images and taxonomical and bibliographical data on more than 4.2 million herbarium specimens. In addition, it contains data on over 49,000 scientific publications. The database can be queried in English, French, and Spanish. The oldest records in the database go back to 1703.
