Bacillus thuringiensis (Bt) is a spore forming (flash animation) bacterium that produces crystals protein (cry proteins), which are toxic to many species of insects.t is largely used in agriculture, especially organic farming. Bt is also used in urban aerial spraying programs, and in transgenic crops. To learn more about each of these topics, click on the corresponding link on the left.
Advantages and Limitations of Ratio Analysis. Financial ratio analysis is a useful tool for users of financial statement. It has following advantages: 1  It simplifies the financial statements.  It helps in comparing companies of different size with each other.
Poisson's ratio deals with the way stretching or compressing an object in one direction causes it to compress or stretch in the other direction. The ratio measures the extent of this effect in a particular substance.This can vary considerably, and the ratio can even be negative, usually in man-made substances.oisson's ratio deals with the way stretching or compressing an object in one direction causes it to compress or stretch in the other direction. The ratio measures the extent of this effect in a particular substance.