.zw

.zw (zimbabwe) is the Internet country code top-level domain (ccTLD) for Zimbabwe.

Although no registry Web site is shown in the IANA whois listing, at least .co.zw registrations are presently being taken by the Zimbabwe Internet Service Providers Association, whose charter claims that one of the purposes of the organization's founding was to oversee the .zw domain.

.ac.zw registrations are being taken by the University of Zimbabwe. Applications are handled by this institution's Computer Centre. As with the general norm, .ac.zw registrations are for academic institutions.

.org.zw registrations are taken by the country's fixed telecommunications provider, TelOne. These are intended for use by NGOs, individuals and such like organisations but any restrictions are not clear.

.zw
ZISPA: Zimbabwe Internet Service Providers Association
Introduced1991
TLD typeCountry code top-level domain
StatusActive
RegistryZISPA
SponsorTelecommunications Regulatory Authority
Intended useEntities connected with  Zimbabwe
Actual useGets some use in Zimbabwe
Registration restrictionsNone
StructureRegistrations are at third level beneath second-level categories
DocumentsTerms and conditions Registration procedure
Registry WebsiteZISPA

External links

Huchra's lens

Huchra's lens is the lensing galaxy of the Einstein Cross (Quasar 2237+30); it is also called ZW 2237+030 or QSO 2237+0305 G. It exhibits the phenomenon of gravitational lensing that was postulated by Albert Einstein when he realized that gravity would be able to bend light and thus could have lens-like effects. The galaxy is named for astronomer John Huchra.

II Zwicky 73

II Zwicky 73 (also known as Zw II 73) is a lenticular and polar-ring galaxy in the constellation Boötes, and about 250 million light years distant from Earth. It is an object of great scientific interest as there have been very few polar ring galaxies discovered. II Zw 73 is a very gas-rich environment. DSS and SDSS images show that it is very similar to polar ring galaxy NGC 660, the best-known of all the polar ring galaxies.

This object is also known as PGC 54461, UGC 9796, MCG+07-31-48, and PRC A-06

I Zw 36

I Zwicky 36, often abbreviated to I Zw 36, is a blue compact dwarf galaxy which is in the constellation Canes Venatici. The dominant population of stars in I Zw 36 is young in stellar terms, with ages of under 3 million years.

Internet in Zimbabwe

The Internet in Zimbabwe has seen rapid expansion in recent years. The Internet country code top-level domain is .zw. In 2009, the Mugabe-Tsvangirai Government of National Unity established a Ministry of Information and Communications Technology to focus on ICT growth and development.

List of ring galaxies

This is a list of ring galaxies. A ring galaxy is a galaxy with a circle-like appearance. Hoag's Object, discovered by Art Hoag in 1950, is the prototypical example of a ring galaxy.

Military Gendarmerie (Poland)

The Military Gendarmerie (Polish: Żandarmeria Wojskowa, abbreviated ŻW) is a military provost and law enforcement agency created in 1990 in Poland as an independent part of the Polish Armed Forces.

Miss Global Zimbabwe

Miss Global Zimbabwe is a National Beauty Pageant in Zimbabwe that was founded in 2012 by Tare Munzara and Ronald Tisauke, that promotes beauty, charity and tourism. The Pageant sends its winner to Miss Globe International and Miss Global International. Its 1st runner up goes to Miss International Pageant. Miss Global Zimbabwe is the only beauty pageant in Zimbabwe that hosts in style, where ticket pricing is expensive and the type of crowd that attends would be Carte Blance, from celebrities, business peoples, diplomats and politicians.

Panzer III

The Panzerkampfwagen III, commonly known as the Panzer III, was a medium tank developed in the 1930s by Germany, and was used extensively in World War II. The official German ordnance designation was Sd.Kfz. 141. It was intended to fight other armoured fighting vehicles and serve alongside and support similar Panzer IV which was originally designed for infantry support. However, as the Germans faced the formidable T-34, more powerful anti-tank guns were needed, and since the Panzer IV had more development potential with a larger turret ring, it was redesigned to mount the long-barrelled 7.5 cm KwK 40 gun. The Panzer III effectively swapped roles with the Panzer IV, as from 1942 the last version of Panzer III mounted the 7.5 cm KwK 37 L/24 that was better suited for infantry support. Production of the Panzer III ceased in 1943. Nevertheless, the Panzer III's capable chassis provided hulls for the Sturmgeschütz III assault gun until the end of the war.

Sex

Organisms of many species are specialized into male and female varieties, each known as a sex. Sexual reproduction involves the combining and mixing of genetic traits: specialized cells known as gametes combine to form offspring that inherit traits from each parent. The gametes produced by an organism define its sex: males produce small gametes (e.g. spermatozoa, or sperm, in animals; pollen in seed plants) while females produce large gametes (ova, or egg cells). Individual organisms which produce both male and female gametes are termed hermaphroditic. Gametes can be identical in form and function (known as isogamy), but, in many cases, an asymmetry has evolved such that two different types of gametes (heterogametes) exist (known as anisogamy).

Physical differences are often associated with the different sexes of an organism; these sexual dimorphisms can reflect the different reproductive pressures the sexes experience. For instance, mate choice and sexual selection can accelerate the evolution of physical differences between the sexes.

Among humans and other mammals, males typically carry an X and a Y chromosome (XY), whereas females typically carry two X chromosomes (XX), which are a part of the XY sex-determination system. Humans may also be intersex. Other animals have different sex-determination systems, such as the ZW system in birds, the X0 system in insects, and various environmental systems, for example in crustaceans. Fungi may also have more complex allelic mating systems, with sexes not accurately described as male, female, or hermaphroditic.

Sex-determination system

A sex-determination system is a biological system that determines the development of sexual characteristics in an organism. Most organisms that create their offspring using sexual reproduction have two sexes. Occasionally, there are hermaphrodites in place of one or both sexes. There are also some species that are only one sex due to parthenogenesis, the act of a female reproducing without fertilization.

In many species, sex determination is genetic: males and females have different alleles or even different genes that specify their sexual morphology. In animals this is often accompanied by chromosomal differences, generally through combinations of XY, ZW, XO, ZO chromosomes, or haplodiploidy. The sexual differentiation is generally triggered by a main gene (a "sex locus"), with a multitude of other genes following in a domino effect.

In other cases, sex of a fetus is determined by environmental variables (such as temperature). The details of some sex-determination systems are not yet fully understood. Hopes for future fetal biological system analysis include complete-reproduction-system initialized signals that can be measured during pregnancies to more accurately determine whether a determined sex of a fetus is male, or female. Such analysis of biological systems could also signal whether the fetus is hermaphrodite, which includes total or partial of both male and female reproduction organs.

Some species such as various plants and fish do not have a fixed sex, and instead go through life cycles and change sex based on genetic cues during corresponding life stages of their type. This could be due to environmental factors such as seasons and temperature. Human fetus genitals can sometimes develop abnormalities during maternal pregnancies due to mutations in the fetuses sex-determinism system, resulting in the fetus becoming intersex.

Sex linkage

Sex linkage describes the patterns of inheritance and presentation when a mutated gene (an allele) is present on a sex chromosome (an allosome) rather than a non-sex chromosome (an autosome). They are characteristically different from the autosomal forms of dominance and recessiveness.

Since humans have several times as many genes on the female X chromosome than on the male Y chromosome, X-linked traits are much more common than Y-linked traits. Additionally, there are more X-linked recessive conditions than X-linked dominant, and X-linked recessive conditions affect males much more commonly, due to males only having the one X chromosome required for the condition to present.

In humans, X-linked traits are inherited from a carrier or affected mother or from an affected father. In X-linked recessive conditions, a son born to an unaffected father and a carrier mother has a 50% chance of inheriting the mother's X chromosome carrying the mutant allele and presenting with the condition. A daughter on the other hand has a 50% chance of being a carrier, however a fraction of carriers may display a milder (or even full) form of the condition due to their body's normal X-inactivation process preferably inactivating a certain parent's X chromosome (the father's in this case), a phenomenon known as skewed X-inactivation. If the condition is dominant, or if the father is also affected, the daughter has a 50% chance of being affected, with an additional 50% chance of being a carrier in the second case. A son born to an affected father and a non-carrier mother will always be unaffected due to not inheriting the father's X chromosome. A daughter on the other hand will always be a carrier (some of which may present with symptoms due to aforementioned skewed X-inactivation), unless the condition is dominant, in which case she will always be affected. There are a few Y-linked traits; these are inherited by sons from their father and are always expressed.

The incidence of X-linked recessive conditions in females is the square of that in males: for example, if 1 in 20 males in a human population are red-green color blind, then 1 in 400 females in the population are expected to be color-blind (1/20)*(1/20).

The inheritance patterns are different in animals which use different sex-determination systems. In the ZW sex-determination system used by birds, the mammalian pattern is reversed, since the male is the homogametic sex (ZZ) and the female is heterogametic (ZW).

In classical genetics, a mating experiment called a reciprocal cross is performed to test if an animal's trait is sex-linked.

Trams in Berlin

The Berlin tramway (German: Straßenbahn Berlin) is the main tram system in Berlin, Germany. It is one of the oldest tram networks in the world having its origins in 1865 and is operated by Berliner Verkehrsbetriebe (BVG), which was founded in 1929. It is notable for being the third-largest tram system in the world, after Melbourne and St. Petersburg. Berlin's streetcar system is made up of 22 lines that operate across a standard gauge network, with almost 800 stops and measuring almost 190 kilometres (120 mi) in route length and 430 kilometres (270 mi) in line length. Nine of the lines, called Metrotram, operate 24 hours a day and are identified with the letter "M" before their number; the other thirteen lines are regular city tram lines and are identified by just a line number.Most of the recent network is within the confines of the former East Berlin—tram lines within West Berlin having been replaced by buses during the division of Berlin (the first extension into West Berlin opened in 1994 on today's M13). In the eastern vicinity of the city there are also three private tram lines that are not part of the main system, whereas to the south-west of Berlin is the Potsdam tram system with its own network of lines.

XY sex-determination system

The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects (Drosophila), some snakes, and some plants (Ginkgo). In this system, the sex of an individual is determined by a pair of sex chromosomes. Females typically have two of the same kind of sex chromosome (XX), and are called the homogametic sex. Males typically have two different kinds of sex chromosomes (XY), and are called the heterogametic sex.

In humans the presence of the Y chromosome determines if an offspring develops as a male and the absence of the Y chromosome results in a female offspring. More specifically it is the SRY gene located on the Y chromosome that is of importance to male differentiation. Variations to the sex gene karyotype could include rare disorders such as XX males (often due to translocation of the SRY gene to the X chromosome) or XY gonadal dygenesis (due to mutations in the SRY gene). In addition, other rare genetic variations such as Turners (XO) and Klinefelters (XXY) are seen as well.

The XY system contrasts in several ways with the ZW sex-determination system found in birds, some insects, many reptiles, and various other animals, in which the heterogametic sex is female. It had been thought for several decades that in all snakes sex was determined by the ZW system, but there had been observations of unexpected effects in the genetics of species in the families Boidae and Pythonidae; for example, parthenogenic reproduction produced only females rather than males, which is the opposite of what is to be expected in the ZW system. In the early years of the 21st century such observations prompted research that demonstrated that all pythons and boas so far investigated definitely have the XY system of sex determination.A temperature-dependent sex determination system is found in some reptiles.

ZW

ZW or zw may refer to:

ZW sex-determination system, in biology

Air Wisconsin (IATA airline designator), a US airline

Zettawatt (ZW), an SI unit of power

Zimbabwe (ISO 3166-1 alpha-2 country code ZW)

.zw, the country code top level domain (ccTLD) for Zimbabwe

ZW sex-determination system

The ZW sex-determination system is a chromosomal system that determines the sex of offspring in birds, some fish and crustaceans such as the giant river prawn, some insects (including butterflies and moths), and some reptiles, including Komodo dragons. The letters Z and W are used to distinguish this system from the XY sex-determination system.

In contrast to the XY sex-determination system and the X0 sex-determination system, where the sperm determines the sex, in the ZW system, the ovum determines the sex of the offspring. Males are the homogametic sex (ZZ), while females are the heterogametic sex (ZW). The Z chromosome is larger and has more genes, like the X chromosome in the XY system.

Zimbabwe

Zimbabwe (), officially the Republic of Zimbabwe, is a landlocked country located in southern Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa, Botswana, Zambia and Mozambique. The capital and largest city is Harare. A country of roughly 16 million people, Zimbabwe has 16 official languages, with English, Shona, and Ndebele the most commonly used.

Since the 11th century, present-day Zimbabwe has been the site of several organised states and kingdoms as well as a major route for migration and trade. The British South Africa Company of Cecil Rhodes first demarcated the present territory during the 1890s; it became the self-governing British colony of Southern Rhodesia in 1923. In 1965, the conservative white minority government unilaterally declared independence as Rhodesia. The state endured international isolation and a 15-year guerrilla war with black nationalist forces; this culminated in a peace agreement that established universal enfranchisement and de jure sovereignty as Zimbabwe in April 1980. Zimbabwe then joined the Commonwealth of Nations, from which it was suspended in 2002 for breaches of international law by its then-government, and from which it withdrew in December 2003. The sovereign state is a member of the United Nations, the Southern African Development Community (SADC), the African Union (AU), and the Common Market for Eastern and Southern Africa (COMESA). It was once known as the "Jewel of Africa" for its prosperity under the former Rhodesian administration.Robert Mugabe became Prime Minister of Zimbabwe in 1980, when his ZANU-PF party won the elections following the end of white minority rule; he was the President of Zimbabwe from 1987 until his resignation in 2017. Under Mugabe's authoritarian regime, the state security apparatus dominated the country and was responsible for widespread human rights violations. Mugabe maintained the revolutionary socialist rhetoric of the Cold War era, blaming Zimbabwe's economic woes on conspiring Western capitalist countries. Contemporary African political leaders were reluctant to criticise Mugabe, who was burnished by his anti-imperialist credentials, though Archbishop Desmond Tutu called him "a cartoon figure of an archetypal African dictator". The country has been in economic decline since the 1990s, experiencing several crashes and hyperinflation along the way.On 15 November 2017, in the wake of over a year of protests against his government as well as Zimbabwe's rapidly declining economy, Mugabe was placed under house arrest by the country's national army in a coup d'état. On 19 November 2017, ZANU-PF sacked Robert Mugabe as party leader and appointed former Vice President Emmerson Mnangagwa in his place. On 21 November 2017, Mugabe tendered his resignation prior to impeachment proceedings being completed. On 30 July 2018 Zimbabwe held its general elections, which was won by the ZANU-PF party led by Emmerson Mnangagwa. Nelson Chamisa who was leading the main opposition party MDC Alliance contested the election results and filed a petition to the Constitution Court of Zimbabwe. The court confirmed Mnangagwa's victory, making him the newly elected president after Mugabe.

Zimbabwe Independent

Zimbabwe Independent is a private weekly published from Harare, Zimbabwe, by Alpha Media Holdings. The company also publishes The Standard and NewsDay.

Zimbabwean dollar

The Zimbabwean dollar (sign: $, or Z$ to distinguish it from other dollar-denominated currencies) was the official currency of Zimbabwe from 1980 to 12 April 2009. During this time, it was subject to periods of above-average inflation, followed by a period of hyperinflation.The Zimbabwean dollar was introduced in 1980 to directly replace the Rhodesian dollar (which had been introduced in 1970) at par (1:1), at a similar value to the US dollar. Over time, hyperinflation in Zimbabwe reduced the Zimbabwe dollar to one of the lowest valued currency units in the world. It was redenominated three times (in 2006, 2008 and 2009), with denominations up to a $100 trillion banknote issued. The final redenomination produced the "fourth dollar" (ZWL), which was worth 1025 ZWD (first dollars).

Use of the Zimbabwean dollar as an official currency was effectively abandoned on 12 April 2009. It was demonetised in 2015, with outstanding accounts able to be reimbursed until April 30, 2016. In place of the Zimbabwean dollar, currencies including the South African rand, Botswana pula, pound sterling, Indian rupee, euro, Japanese yen, Australian dollar, Chinese yuan, and the United States dollar are now regularly used.

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