Abstract: A coprecipitant and a nucleic-acid extraction method using the coprecipitant are provided. The coprecipitant has affinity to the nucleic acids, no competitive inhibition to the reverse transcription and no inhibition to the PCR reaction in case of extracting a very small amount of nucleic acids by alcoholic precipitation using isopropyl alcohol or ethanol. Further, the coprecipitant can precipitate with the nucleic acids as a visible white or blue precipitate, thereby to suppress technical errors and enhance the extraction efficiency. A coprecipitant which acts in a process of extracting the nucleic acids by centrifugal separation from biological materials and/or test samples in the same manner as nucleic acids and has ability for precipitating as a visible white or blue precipitate when being separating and concentrating it by alcohol.

Abstract: In order to sensually grasp, during operation, the direction in which one is trying to switch the viewpoint and/or aim on a display device, even if the purpose is, for example, to knock down an opponent, a program execution device includes an aim/viewpoint selection means or function, which judges whether the operation input from the user is a viewpoint switching instruction or an aim switching instruction, a viewpoint switching processing means or function, which performs viewpoint switching processing if the result of the judgment in the aim/viewpoint selection means is that it is a viewpoint switching instruction, and an aim switching processing means, to perform aim switching processing if the result of the judgment in the aim/viewpoint selection means is that it is an aim switching instruction.

Abstract: In order to sensually grasp, during operation, the direction in which one is trying to switch the viewpoint and/or aim on a display device, even if the purpose is, for example, to knock down an opponent, a program execution device includes an aim/viewpoint selection means or function, which judges whether the operation input from the user is a viewpoint switching instruction or an aim switching instruction, a viewpoint switching processing means or function, which performs viewpoint switching processing if the result of the judgment in the aim/viewpoint selection means is that it is a viewpoint switching instruction, and an aim switching processing means, to perform aim switching processing if the result of the judgment in the aim/viewpoint selection means is that it is an aim switching instruction.