Causes cold water pollution

A layer of cold water forms deep within large dams contained by walls higher than 15 metres. It is from this bottom layer that water is typically released through the outlets in the older, major dams of NSW.The water released can be up to 12 C colder than the water in the river upstream of the dam. Large volumes of cold water flowing from dams lower the natural temperature of the river downstream, damaging aquatic ecology over long distances. The effect is greatest during the warmer months from Spring to Autumn when large volumes of water are released for irrigation.

Etymology and definitions

The English word 'emotion' is derived from the French émotion and émouvoir. This is based on the Latin emovere, where e- (variant of ex-) means 'out' and movere means 'move'. The related term "motivation" is also derived from movere. Emotions can be divided between 'cognitive' theories of emotions and 'non-cognitive' theories of emotions; or instinctual emotions (from the amgdala), and cognitive emotions (from the prefrontal cortex). Some psychologists divide emotions into basic and complex categories, where base emotions lead to more complex ones. Emotions can be categorized by its duration. Some emotions occur over a period of seconds (e.g. surprise) where others can last years (e.g. love). No definitive taxonomy exists.

A related distinction is between the emotion and the results of the emotion, principally behaviours and emotional expressions. People often behave in certain ways as a direct result of their emotional state, such as crying, fighting or fleeing. Yet again, if one can have the emotion without the corresponding behaviour then we may consider the behaviour not to be essential to the emotion. However some theorists such as the Dutch psychologist Nico Frijda hold a functionalist approach to emotions. Frijda argues that emotions have evolved for a particular function, such as to keep the subject safe. If the behaviours associated with an emotion are the determining factor for the very existence of that emotion then goal-directed behaviour should be regarded as essential to the emotion. Yet since we recognise that the behaviour need not necessarily occur, we can stipulate that emotions involve what are called 'action tendencies'. So for instance, fear involves the tendency to flee, which means that the probability that the subject will flee from a given situation is increased when he is undergoing fear.

Emotion

An emotion is a term for a mental and physiological state associated with a wide variety of feelings, thoughts, and behavior. Emotions are subjective experiences, or experienced from a individual point of view. Emotion is often associated with mood, temperament, personality, and disposition. For example: confused, excited, guilty, anxious, angry, sad, confident, embarrassed, happy, disgusted, frightened, cautious, smug, lonely, lovestruck, joy, jealous, surprised, shy, apathetic, powerful, unfair, pleasure, and euphoric.

Hearing

Hearing or audition is the sense of sound perception. Since sound is vibrations propagating through a medium such as air, the detection of these vibrations, that is the sense of the hearing, is a mechanical sense akin to a sense of touch, albeit a very specialized one. In humans, this perception is executed by tiny hair fibres in the inner ear which detect the motion of a membrane which vibrates in response to changes in the pressure exerted by atmospheric particles within a range of 20 to 22000 Hz, with substantial variation between individuals. Sound can also be detected as vibrations conducted through the body by tactition. Lower and higher frequencies than that can be heard are detected this way only. The inability to hear is called deafness.

Gatling gun

The Gatling gun is considered by some to have been the very first machine gun: although it did not automatically reload under its own power, it was capable of firing continuously. Each barrel fires a single shot as it reaches a certain point in the cycle after which it ejects the spent cartridge, loads a new round, and in the process, somewhat cools down. This configuration allowed higher rates of fire without the problem of an overheating single barrel. The Maxim gun, invented in 1884, was the first self-powered machine gun. The first Gatling gun relied on a hand crank for external power. Some time later, Gatling-type weapons were invented that diverted a fraction of gas from the chamber to turn the barrels. Later still, electric motors supplied external power. The gun was designed by the American inventor Dr. Richard J. Gatling in 1861 and patented in 1862.