Teleosts are the dominant fish of the present day. They arose in the Mesozoic era, and include 20,000 living species. The oldest teleost fossils date back to the late Triassic. They evolved from fish like bowfins in the clade Holostei. During the Mesozoic and Cainozoic they diversified. 96 percent of all known fish species are teleosts.
They are, in order of evolution, vertebrates, jawed fish (Gnathostomata), bony fish (Osteichthyes) and ray-finned fish (Actinopterygii).
Teleosts have a movable jaw and changes in the jaw muscles. These changes make it possible for them to protrude their jaws outwards from the mouth. This adaptation improves their ability to grab fast-moving prey.
The date of origin of the teleosts is a difficult problem. Two kinds of evidence are available. There is evidence from the fossil record, in which the first teleost comes from the late Triassic period.
This date is somewhat later than molecular divergence time estimates (molecular clock). A recent paper finds that fossil dates and molecular clock dates are similar to each other. These researchers atate:
Teleostei
Fresh water
Fresh water (also 'freshwater' or 'fresh-water') is water that does not have a lot of salt in it.
When people say 'fresh water', they usually mean water from the lakes, rivers, snow, and ice, which is not salty. It also can mean water that people can drink. The oceans and seas are made up of salt water, which people cannot drink. Most of the world's fresh water is in the ice sheet of Antarctica.
People cannot drink all fresh water, because it might be contaminated. It might have harmful bacteria in it, or poisonous because of chemicals it contains. Water from a tap has been tested and treated so that it is safe to drink. This applies to most countries, but in some place the water needs to be boiled first to kill the germs and drunk after it has cooled down.
Fresh water that people can drink safely is called 'potable water'. Desalination can turn salt water into drinkable water.
Grand Theft Auto: Vice City
Grand Theft Auto: Vice City is a video game developed by Rockstar North and published by Rockstar Games. It was released in 2002, for the PlayStation 2 and for personal computers. It is part of the "Grand Theft Auto" series of video games. It takes place in the middle of the 80's in a fictional place called Vice City. This fictional city is based on the real-life city called Miami which is in Florida state.
"Grand Theft Auto: Vice City" is an action-adventure game played from a third-person view. The player controls criminal Tommy Vercetti and completes missions to progress through the story. Players can freely walk around the game's open world and can complete side missions too. Vice City has has two main islands and some smaller islands. The islands are unlocked for the player as the story progresses.
The player can run, jump, and drive vehicles. The player uses melee attacks, firearms and explosives to fight enemies.
During the story, Tommy meets different gangs. As the player completes missions for different gangs, some gang members will defend the player and some rival gang members will see the player and shoot them.
As Tommy builds his criminal empire, the player can buy a number of buildings in the city, some are where weapons can be collected and vehicles can be stored. There are also businesses which can be purchased.
Each building has a number of missions, once all missions are complete, the building begins to generate an ongoing income for the player.
WrestleMania XXVII
WrestleMania XXVII was the twenty-seventh yearly WrestleMania professional wrestling pay-per-view (PPV) event made by World Wrestling Entertainment (WWE). It took place at the Georgia Dome in Atlanta, Georgia.
In September 2009, it was reported that the city of Atlanta was wanting to have WrestleMania XXVII at the Georgia Dome. A press conference was held on February 1, 2010 at the Georgia Dome to officially announced the event for Atlanta; this will be the first WrestleMania to be held in the state of Georgia. Along with WrestleMania XXVII, a group of events known as "WrestleMania Week" will be held in the week before the event including WrestleMania's yearly "WrestleMania Axxess" fan convention, the 2011 WWE Hall of Fame ceremony, the fourth yearly "WrestleMania Art" showing and auction, and a Celebrity Pro-Am Golf tournament. According to the president of the Atlanta Sports Council, Gary Stokan, "WrestleMania Axxess" is planned to be held at the Georgia World Congress Center, while the WWE Hall of Fame ceremony will take place either at the Fox Theatre or at Philips Arena.
Between 15 and 20 cities were thought of to host the event, with fewer than half of the people thought of invited to explain why they should hold the event at WWE's headquarters at Stamford, Connecticut. Atlanta's main rival to hosting the event was the city of Miami, Florida who wanted to host the event at Sun Life Stadium along with "WrestleMania Axxess" at the Convention Center and the WWE Hall of Fame ceremony at the American Airlines Arena. Miami was later given WrestleMania XXVIII.
During the pay-per-view, Justin Roberts announced a new Georgia Dome "entertainment" attendance record of 71,617. But a Billboard.com article claims a Backstreet Boys concert had 73,337 people in attendance. WWE says in their official press release that the Backstreet Boys concert only had 65,658 people in attendance. WWE's number was later confirmed by officials at the Georgia Dome.
Enthalpy
Enthalpy is a concept used in science and engineering when heat and work need to be calculated. The name comes from the Greek word "enthalpos" (ενθαλπος), meaning "to put heat into". The idea and the word were made up by the Dutch scientist Heike Kamerlingh Onnes in 1909.
When a substance changes at constant pressure, enthalpy tells how much heat and work was added or removed from the substance.
Enthalpy is similar to energy, but not the same. When a substance grows or shrinks, energy is used up or released. Enthalpy accounts for this energy. Because of this, scientists often calculate the change in enthalpy, rather than the change in energy.
Consider a system containing a fixed amount of gas. Any heat energy entering the system will:
1) Increase the Internal Energy of the gas
or
2) Lead to some work being done to expand the system.
The work done is the product of pressures and volume. Enthalpy takes both these factors into account, therefore:
When a chemical reaction happens, a substance can become warmer or colder. As a result, heat will flow to things around it, or from things around it, until its temperature is the same again. If the pressure stays the same, this amount of heat tells how much the enthalpy changed.
For example, if gasoline is burned in the open air, heat is released by the gasoline. If we suppose 100 kilojoules of heat were released, then the enthalpy of the gasoline was reduced by 100-kilo joules. Therefore the change in enthalpy for this reaction was ∆"H" = –100 kJ.
If a chemical reaction gives off heat (warming its surroundings), then the enthalpy of the reaction is said to have decreased. The value of ∆"H" is negative. This kind of reaction, like the example above, is called exothermic.
If a chemical reaction absorbs heat (cooling its surroundings), then the reaction's enthalpy has increased. The value of ∆"H" is positive. This is called an endothermic reaction.
MRSA
MRSA is a strain of Methicillin-resistant "Staphylococcus aureus". This is a bacterium which causes infections in different parts of the body. It is tougher to treat than other strains of "Staphylococcus aureus" – or 'staph' – because it is resistant to some commonly used antibiotics. In fact, it is now resistant to all forms of penicillin and cephalosporin.