Algebra, from the Arabic word al-jabr, meaning "reunion of broken parts," is the study of variables and the rules for manipulating these variables in formulas; it is the unifying thread of almost all of mathematics. Elementary algebra deals with the manioulation of variables (commonly represented by Roman letters) as if they were numbers and is therefore essential in all applications of mathematics. Abstract algebra is the name given, mostly in education, to the study of algebraic structures such as groups, rings, and fields. Linear algebra, which deals with linear equations and linear mappings, is used for modern presentations of geometry, and has many practical applications (in weather forecasting, for example). There are many areas of nathematics that belong to algebra, some having "algebra" in their name, such as communitative algebra, and some have not, such as Galois theory. The word algebra is not only used for naming an area of mathematics and some subareas...

Food microbiology is the study of the microorganisms that inhabit, create or contaminate food. This includes the study of microorganisms causing spoilage; pathogens that may cause disease (especially if the food is improperly cooked or stored); microbes used to produce fermented foods such as cheese, yogurt, bread, beer, and wine; and microbes with other useful roles, such as producing probiotics. In the study of bacteria in food, important groups have been subdivided based on certain characteristics. These groupings are not of taxonomic significance: Lactic acid bacteria are bacteria that use carbohydrates to produce lactic acid. The main genera are Lactococcus, Leoconostoc, Pediococcus, Lactobacillus, and Streptococcus thermophilus. Acetic acid bacteria like Acetobacter aceti produce acetic acid. Bacteria such as Propionibacterium freudenrencii that produce propionic acid are used to ferment dairy products. Some Clostridium spp. Clostridium butyricum produce butyric acid. Proteolytic...

A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refers to the six classical simple machines that were defined by Renaissance scientists: Lever Wheel and axle Pulley Inclined plane Wedge Screw A simple machine uses a single applied force to do work against a single work load. Ignoring friction losses, the work done on the load is equal to the work done by the applied force. The machine can increase the amount of the output force, at the cost of a proportional decrease in the distance moved by the load. The ratio of the output to the applied force is called the mechanical advantage. Simple machines can be regarded as the elementary "building blocks" of which all more complicated machines (sometimes called compound machines) are composed. For example, wheels, levers, and pulleys are all use...

Keynesian economics (sometimes Keynesianism, named after the British economist John Maynard Keynes) are the various macroeconomic theories and models on how aggregate demand (total spending in the economy) strongly influences economic output and inflation. In the Keynesian view, aggregate demand does not necessarily equal the productive capacity of the economy. Instead, it is influenced by a host of factors (sometimes behaving erratically) affecting production, employment, and inflation. Keynesian economists generally argue that aggregate demand is volatile and unstable and that, consequently, a market economy often experiences inefficient macroeconomic outcomes - a recession, when demand is low, or inflation, when demand is high. Further, they argue that these economic fluctuations can be mitigated by economic policy responses coordinated between government and the central bank. In particular, fiscal policy actions (taken by the government) and monetary policy actions (taken by the ce...

Criminal psychology is the study of the views, thoughts, intentions, actions and reactions of criminals or suspects. It is a subfield of criminology and applied psychology. Criminal psychologists have many roles within legal courts, including being called upon as expert witnesses and performing psychological assessments. Some types of psychiatry also deals with aspects of criminal behavior. Several definitions are used for criminal behavior, including behavior punishable by public law, behavior considered immoral, behavior violating social norms or traditions, or acts causing severe psychological harm. Criminal behavior is often considered antisocial in nature. Criminal psychology started in the late 18th century. There were four key aspects of the development of criminal psychology: philosophical, medical, legal and biological. Before criminal psychology, there was a conflict in criminal law between medical experts and court judges on determining how to proceed with a majority of case...

 The term "white-collar crime" refers to financially motivated, nonviolent or non directly violent crime committed by individuals, businesses and government professionals. It was first defined by the sociologist Edwin Sutherland in 1939 as "a crime committed by a person of respectability and high social status in the course of their occupation." Typical white-collar crime includes wage theft, fraud, bribery, Ponzi scheme, inside trading, labor racketeering, embezzlement, cybercrime, copyright infringement, money laundering, identity theft, and forgery. White-collar crime overlaps with corporate crime. Modern criminology prefers to classify the type of crime and the topic: By the type of offense, e.g., property crime, economic crime, and other corporate crimes like environmental and health, and safety law violations. Some crime is only possible because of the identity of the offender, e.g., transnational money laundering requires the participation of senior officers ...

An interest rate is the amount of interest due per period, as a proportion of the amount lent, deposited, or borrowed (called the principal sum). The total interest on an amount lent or borrowed depends on the principal sum, the interest rate, the compounding frequency, and the length of time over which it is lent, deposited, or borrowed. The annual interest rate is the rate over a period of one year. Other interest rates apply over different periods, such as a month or day, but they are usually annualized. The interest rate has been characterized as "an index of the preference . . . for a dollar of (present) income over a dollar of future income." The borrower wants, or needs, to have money sooner rather than later, and is willing to pay a fee - the interest rate - for that privilege. Interest rates vary according to: the government's directives to the central bank to accomplish the government's goals the currency of the principal sum lent or borrowed the term to mat...