Depression (mood)

In the fields of psychology and psychiatry, depression refers to a state of low mood and aversion to activity. While most often described as a disease or dysfunction, there are also strong arguments for seeing depression as an adaptive defence mechanism.

The Diagnostic and Statistical Manual of Mental Disorders defines a depressed person as experiencing feelings of sadness, helplessness and hopelessness. In traditional colloquy, "depressed" is often synonymous with "sad", but both clinical depression and non-clinical depression can also refer to a conglomeration of more than one feeling.

Biological influences of depression are varied, but may relate to malnutrition, heredity, hormones, seasons, stress, illness, drug or alcohol use, neurotransmitter malfunction, long-term exposure to dampness and mold^[1], back injury, and to aerosol exposure. There are also correlations between long term sleep difficulties and depression. Up to 90% of patients with depression are found to have sleep difficulties.
http://en.wikipedia.org/wiki/Depression_(mood)

phobia

A phobia is an irrational, intense, persistent fear of certain situations, activities, things, or people. The main symptom of this disorder is the excessive, unreasonable desire to avoid the feared subject. When the fear is beyond one's control, and if the fear is interfering with daily life, then a diagnosis under one of the anxiety disorders can be made.^[1]

Phobias (in the clinical meaning of the term) are the most common form of anxiety disorders. An American study by the National Institute of Mental Health (NIMH) found that between 8.7% and 18.1% of Americans suffer from phobias.^[2] Broken down by age and gender, the study found that phobias were the most common mental illness among women in all age groups and the second most common illness among men older than 25.

phobias arise from a combination of external events and internal predispositions. In a famous experiment, Martin Seligman used classical conditioning to establish phobias of snakes and flowers. The results of the experiment showed that it took far fewer shocks to create an adverse response to a picture of a snake than to a picture of a flower, leading to the conclusion that certain objects may have a genetic predisposition to being associated with fear.^[3] Many specific phobias can be traced back to a specific triggering event, usually a traumatic experience at an early age. Social phobias and agoraphobia have more complex causes that are not entirely known at this time. It is believed that heredity, genetics, and brain chemistry combined with life-experiences play a major role in the development of anxiety disorders, phobias and panic attacks.
http://en.wikipedia.org/wiki/Phobia

Phobia

A phobia is a strong, persistent fear of situations, objects, activities, or persons.

The main symptom of this disorder is the excessive, unreasonable desire to avoid the feared subject.

Some therapists use virtual reality or imagery exercise to desensitize patients to the feared thing..

For more information about the topic Phobia, read the full article at wikipedia.org, or see the following related articles:

Panic attack— A panic attack is a period of intense, often temporarily disabling sense of extreme fear or psychological distress, typically of abrupt onset. Though ... > read more

Neurosis— In modern psychology, the term neurosis, also known as psychoneurosis or neurotic disorder, is a general term that refers to any mental imbalance ... > read more
Eating disorder-An eating disorder is a compulsion in which the main problem is a person eats in a way which disturbs their physical health. The eating may be too ... > read more

Fear— Fear is an unpleasant feeling of perceived risk or danger, whether it be real or imagined. Fear also can be described as a feeling of extreme dislike ... > read more

source: http//www.sciencedaily.com.articles/p/phobia.htm

Eating disorder

An eating disorder is a compulsion in which the main problem is a person eats in a way which disturbs their physical health.

The eating may be too excessive (compulsive over-eating), too limited (restricting), may include normal eating punctuated with episodes of purging, may include cycles of binging and purging, or may encompass the ingesting of non-foods.

The best-known eating disorders are Anorexia nervosa, Bulimia nervosa, and Pica..

For more information about the topic Eating disorder, read the full article at wikipedia.org, or see the following related articles:

Bulimia nervosa— Bulimia nervosa, more commonly known as bulimia, is an eating disorder. It is a psychological condition in which the subject engages in recurrent ... > read more

Appetite— The appetite is the desire to eat food, felt as hunger. Appetite is regulated by a close interplay between the digestive tract, adipose tissue and ... > read more

Anorexia nervosa— Anorexia nervosa is an eating disorder characterized by voluntary starvation and exercise stress. Anorexia nervosa is a complex disease, involving ... > read more

Hyperglycemia — Hyperglycemia or High Blood Sugar is a condition in which an excessive amount of glucose circulates in the blood plasma. Hyperglycemia is one of the ...
source: http//www.sciencedaily.com/articles/e/eating_disorder.html

Tsunami

tsunami (tsoonä'mē) [key], series of catastrophic ocean waves generated by submarine movements, which may be caused by earthquakes, volcanic eruptions, landslides beneath the ocean, or an asteroid striking the earth. Tsunamis are also called seismic sea waves or, popularly, tidal waves.

In the open ocean, tsunamis may have wavelengths of up to several hundred miles and travel at speeds up to 500 mi per hr (800 km per hr), yet have wave heights of less than 3 ft (1 m), which pass unnoticed beneath a ship at sea. The period between the crests of a tsunami's waves varies from 5 min to about 1 hr. When tsunamis approach shallow water along a coast, they are slowed, causing their length to shorten and their height to rise sometimes as high as 100 ft (30 m). When they break, they often destroy piers, buildings, and beaches and take human life. The wave height as they crash upon a shore depends almost entirely upon the submarine topography offshore. Waves tend to rise to greater heights along gently sloping shores, along submarine ridges, or in coastal embayments.

There is little warning of approach; when a train of tsunami waves approaches a coastline, the first indication is often a sharp swell, not unlike an ordinary storm swell, followed by a sudden outrush of water that often exposes offshore areas as the first wave trough reaches the coast. After several minutes, the first huge wave crest strikes, inundating the newly exposed beach and rushing inland to flood the coast. Generally, the third to eighth wave crests are the largest.

Since tsunamis principally occur in the Pacific Ocean following shallow-focus earthquakes over magnitude 6.5 on the Richter scale, one of the best means of prediction is the detection of such earthquakes on the ocean floor with a seismograph network (see seismology). Tsunamis may be detected by wave gauges and pressure monitors, such as those emplaced as part of the U.S. Tsunami Warning System; established in 1949 and originally confined to the Pacific region, the system has been expanded to the Caribbean and the W North Atlantic. An early warning system for the Indian Ocean began operating in 2006. Measurement of sudden sea level changes from satellites are also used to warn of a potential tsunami.

One of the most destructive tsunamis to occur during historical times followed the explosive eruption of the volcano Krakatoa in the East Indies on Aug. 27, 1883, when over 36,000 people were killed as a result of the wave. Waves were up to 100 ft (30 m) high. Its passage was traced as far away as Panama. On Dec. 26, 2004, a 9.1–9.3 earthquake off NW Sumatra, Indonesia, caused a tsunami with waves as high as 65 ft (20 m) nearest the epicenter. At least 200,000 people are believed to have died. The waves devastated many areas in the E Indian Ocean basin, particularly the nearby coast of N Sumatra, the Andaman and Nicobar Islands, and the E and S coasts of Sri Lanka. Areas of SE India and SW Thailand were also hard hit. Deaths and destruction occurred as far away as the coasts of Somalia and Madagascar in Africa, and minor sea level changes were measured as far away as San Diego, Calif., Iquique, Chile, and Atlantic City, N.J. It is believed that a 0.6-mi-wide (1-km-wide) asteroid that struck the ocean SW of New Zealand about A.D. 1500 created a tsunami that reached heights of more than 425 ft (130 m).

http://www.infoplease.com/ce6/sci/A0849598.html

Technology

By the mid 20th century, humans had achieved a mastery of technology sufficient to leave the atmosphere of the Earth for the first time and explore space.

Technology is a broad concept that deals with an animal species' usage and knowledge of tools and crafts, and how it affects an animal species' ability to control and adapt to its environment. Technology is a term with origins in the Greek "technologia", "τεχνολογία" — "techne", "τέχνη" ("craft") and "logia", "λογία" ("saying").^[1] However, a strict definition is elusive; "technology" can refer to material objects of use to humanity, such as machines, hardware or utensils, but can also encompass broader themes, including systems, methods of organization, and techniques. The term can either be applied generally or to specific areas: examples include "construction technology", "medical technology", or "state-of-the-art technology".

The human species' use of technology began with the conversion of natural resources into simple tools. The prehistorical discovery of the ability to control fire increased the available sources of food and the invention of the wheel helped humans in travelling in and controlling their environment. Recent technological developments, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact freely on a global scale. However, not all technology has been used for peaceful purposes; the development of weapons of ever-increasing destructive power has progressed throughout history, from clubs to nuclear weapons.

Technology has affected society and its surroundings in a number of ways. In many societies, technology has helped develop more advanced economies (including today's global economy) and has allowed the rise of a leisure class. Many technological processes produce unwanted by-products, known as pollution, and deplete natural resources, to the detriment of the Earth and its environment. Various implementations of technology influence the values of a society and new technology often raises new ethical questions. Examples include the rise of the notion of efficiency in terms of human productivity, a term originally applied only to machines, and the challenge of traditional norms.

Philosophical debates have arisen over the present and future use of technology in society, with disagreements over whether technology improves the human condition or worsens it. Neo-Luddism, anarcho-primitivism, and similar movements criticise the pervasiveness of technology in the modern world, opining that it harms the environment and alienates people; proponents of ideologies such as transhumanism and techno-progressivism view continued technological progress as beneficial to society and the human condition. Indeed, until recently, it was believed that the development of technology was restricted only to human beings, but recent scientific studies indicate that other primates and certain dolphin communities have developed simple tools and learned to pass their knowledge to other generations.

source : http://en.wikipedia.org/wiki/Technology

A genetically modified organism (GMO) or genetically engineered organism (GEO) is an organism whose genetic material has been altered using genetic engineering techniques. These techniques, generally known as recombinant DNA technology, use DNA molecules from different sources, which are combined into one molecule to create a new set of genes. This DNA is then transferred into an organism, giving it modified or novel genes. Transgenic organisms, a subset of GMOs, are organisms which have inserted DNA that originated in a different species. Some GMOs contain no DNA from other species and are therefore not transgenic but cisgenic.
source : http://en.wikipedia.org/wiki/GMO#Production