Although it has never officially been released, the Dreamcast version was leaked onto the Internet, and was proven fully playable. The leak contains the full versions of Half-Life and Blue Shift , both with an early version of the High Definition Pack (it was from this port that the pack was spawned). Although, the leak has a somewhat inconsistent frame rate (though never to the point of unplayability) and lengthier load times when the player moves from area to area (around ten seconds, while today's average PC can load an area in around one and a half). In addition, there are some saving problems; the number of blocks required to save on a VMU increases rapidly as the player reaches the end of a level, then drops at the start of the next. While the game allows the player to remove files to increase space, sometimes it still isn't enough.
The duration of action of a drug is known as its half life. This is the period of time required for the concentration or amount of drug in the body to be reduced by one-half. We usually consider the half life of a drug in relation to the amount of the drug in plasma. A drug's plasma half-life depends on how quickly the drug is eliminated from the plasma. A drug molecule that leaves plasma may have any of several fates. It can be eliminated from the body, or it can be translocated to another body fluid compartment such as the intracellular fluid or it can be destroyed in the blood. The removal of a drug from the plasma is known as clearance and the distribution of the drug in the various body tissues is known as the volume of distribution . Both of these pharmacokinetic parameters are important in determining the half life of a drug.