Pro tempore (abbreviated pro tem or p.t.) is a Latin phrase which means "for the time being" in English. This phrase is often used to describe a person who temporarily acts in place of an elected or appointed official. Should the official, a mayor for example, be absent or unavailable for any reason, the pro tempore becomes the acting official (acting mayor in this case). The president pro tempore of the United States Senate has been elected by the Senate since it began 1789. In academic use a professor pro tempore is usually a temporary position. In legal use a judge pro tempore is often an attorney who has been temporarily appointed by a judge. It is also found as a phrase in many kinds of documents to simply mean "for the time being."
Restriction enzyme
A restriction enzyme is an enzyme that cuts DNA at particular places. It works at or near specific recognition nucleotide sequences known as "restriction sites". To cut DNA, all restriction enzymes make two incisions, once through each strand of the DNA double helix.
These enzymes are found in bacteria and archaea and defend them against invading viruses, which are bacteriophages.
Inside a prokaryote, the restriction enzymes selectively cut up "foreign" DNA in a process called "restriction". The host DNA is protected by another enzyme which protects the host DNA and blocks cleavage. Together, these two processes are the restriction modification system. It is the earliest and simplest immune system. They are also a kind of selfish, mobile genetic element.
Over 3000 restriction enzymes have been studied in detail, and more than 600 of these are available commercially. These enzymes are routinely used for DNA modification in laboratories, and are a vital tool in molecular cloning.
Restriction enzymes probably evolved from a common ancestor and became widespread by horizontal gene transfer. In addition, there is growing evidence that restriction endonucleases evolved as a selfish genetic element.
Population control in Singapore
Population control in Singapore had two distinct phases. First, to slow and reverse the boom in births that started after World War II. Second, from the 1980s, to encourage parents to have more children because numbers had fallen below replacement levels.
In the 1960s and 1970s, The Family Planning and Population Board (FPPB) was set up. At first it favoured small families, and later ran the Stop at Two programme. This pushed for small two-children families and promoted sterilisation.
As birthrates fell, so the government introduced a policy that encouraged having three or more children.
Selfish DNA
Selfish DNA is a term for sequences of DNA that have two distinct properties:
In his 1976 book, "The Selfish Gene", Richard Dawkins suggested the idea of selfish DNA when the noncoding DNA in eukaryotic genomes was discovered. In 1980, two articles in the journal "Nature" expanded and discussed the concept. According to one of these articles:
Normal genetically functional DNA might be seen as "replicating entities" that effect their replication by manipulating the cell that they control. In contrast, units of selfish DNA may exploit existing mechanisms in the cell, and multiply without affecting the fitness of the organism in other respects.
There is no sharp boundary between the concepts of selfish DNA and genetically functional DNA. Often it also is difficult to see if a unit of noncoding DNA is functionally important or not; or if important, in what way. What is more, it is not always easy to distinguish between some instances of selfish DNA and some types of viruses.
The idea that some genetic elements might not be useful to the organism is not a new one. In 1928, a Russian geneticist reported an X chromosome in "Drosophila obscura". He claimed that the resulting female-biased sex ratio might drive a population extinct.
In 1941 it was first suggested that there might be a conflict between normal inherited nuclear genes from both parents and mitochondrial genes from one parent (the female). It could lead to cytoplasmic male sterility in plants.
Around the same time, several other examples of selfish genetic elements were reported. For example, a maize geneticist described how chromosomal knobs led to female meiotic drive in maize. Meiotic drive is when one copy of a gene is passed on to offspring more than the expected 50% of the time.
The Swedish botanist and cytogeneticist Gunnar Östergren in 1945 noted how chromosomes may spread in a population because of their own ”parasitic” nature. Discussing B chromosomes in plants he wrote: ”In many cases these chromosomes have no useful function at all to the species carrying them, but that they often lead an exclusively parasitic existence … [B chromosomes] need not be useful for the plants. They need only be useful to themselves.” - Gunnar Östergren.
Then, in the early 1950s, Barbara McClintock published a series of papers describing the existence of "transposable elements". These are among the most successful selfish genetic elements. The discovery of transposable elements led to her being awarded the Nobel Prize in Medicine or Physiology in 1983.
Jack Stewart (ice hockey)
Jack Stewart was a Canadian professional ice hockey player. He played for the Detroit Red Wings and the Chicago Blackhawks. He is in the Hockey Hall of Fame.
Mullsjö, Nordmaling Municipality
Mullsjö is a minor locality in Nordmaling Municipality, Sweden. In 2010, 76 people lived there.
Bruksvallsloppet
Bruksvallsloppet is an international cross-country skiing event, held in Bruksvallarna, Sweden over a Friday-Sunday in November every year. The event acts as FIS World Cup preselection. The competitions are international. During some seasons the event is the final before the World Cup opens. During other seasons, the event instead occurs between World Cupe events. This depends on if the FIS World Cup starts by late October, or if it begins by mid-late November.
In Sweden, the event is generally considered the first major competition of the season.
Olsfors
Olsfors is a locality in Bollebygd Municipality in Västra Götaland County in Sweden. In 2010, 623 people lived there.
Orrefors
Orrefors is a locality in Nybro Municipality in Kalmar County in Sweden. In 2010, 719 people lived there 2010. The Orrefors glassworks are located there.
Blomstermåla
Blomstermåla is a locality in Mönsterås Municipality in Kalmar County in Sweden. In 2010, 1,527 people lived there.
Kode
Kode is a locality in Kungälv Municipality in Västra Götaland County in Sweden. In 2010, 1,380 people lived there.
100 Things to Do Before High School
100 Things to Do Before High School is an American sitcom airs on Nickelodeon. The series premiered November 11, 2014. It is created by Scott Fellows who also created "Ned's Declassified School Survival Guide" and "Big Time Rush". It stars Isabela Moner, Jaheem Toombs and Owen Joyner.
Marco Minghetti
Marco Minghetti (November 18, 1818 - December 10, 1886) was an Italian economist and statesman.
Minghetti was born at Bologna into a family of rich landowners. In March 1848 Pope Pius IX offered to him the post of minister in the first constitutional government of the Papal States. However, on 29 April 1848, after the speech with which Pius IX announced the withdrawal of the papal army from the front of the first italian war of independence, Minghetti resigned.
Member of the "Historical Right", he was Minister of the Interior in the governments led by Camillo Benso, Count of Cavour and Bettino Ricasoli. He was also Minister of the Treasury in the government led by Luigi Carlo Farini. He was twice Prime Minister of the Kingdom of Italy: from 24 March 1863 to 28 September 1864 and from 10 July 1873 to 25 March 1876.