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Abietic Acid Dermatitis
Abietic acid dermatitis is a contact dermatitis often seen in association with musical instruments. Causes The main cause is a type-I hypersensitivity reaction to products containing abietic acid, such as the rosin/colophony, which is commonly used as a friction-increasing agent. Players of bowed string instruments (violin, viola, cello, double bass) rub cakes or blocks of rosin on their bow so it can grip the strings. Ballet and flamenco dancers sometimes rub their shoes in powdered rosin to reduce slippage before going on stage. Gymnasts, baseball pitchers and ten pin bowlers use rosin to improve grip. Common locations of this contact dermatitis are hands, face and neck. It has also occurred as a result of dehydroabietic acid in an over-the-counter hydrocolloid dressing. Diagnosis Differential diagnosis Cutaneous disorders in musicians include frictional injury ("fiddler's neck"), hyperhidrosis, acne mechanica and vascular compromise. Other agents of irritant and allergic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contact Dermatitis
Contact dermatitis is a type of acute or chronic inflammation of the skin caused by exposure to chemical or physical agents. Symptoms of contact dermatitis can include itchy or dry skin, a red rash, bumps, blisters, or swelling. These rashes are not contagious or life-threatening, but can be very uncomfortable. Contact dermatitis results from either exposure to allergens ( allergic contact dermatitis), or irritants (irritant contact dermatitis). Allergic contact dermatitis involves a delayed type of hypersensitivity and previous exposure to an allergen to produce a reaction. Irritant contact dermatitis is the most common type and represents 80% of all cases. It is caused by prolonged exposure to irritants, leading to direct injury of the epidermal cells of the skin, which activates an immune response, resulting in an inflammatory cutaneous reaction. Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight. Diagnosis of allergic contact dermatitis ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ten-pin Bowling
Ten-pin bowling is a type of bowling in which a bowler rolls a bowling ball down a wood or synthetic lane toward ten pins positioned evenly in four rows in an equilateral triangle. The objective is to knock down all ten pins on the first roll of the ball (a strike), or failing that, on the second roll (a spare). An approximately long ''approach'' area used by the bowler to impart speed and apply rotation to the ball ends in a ''foul line''. The , lane is bordered along its length by ''gutters'' (''channels'') that collect errant balls. The lane's long and narrow shape limits straight-line ball paths to angles that are smaller than optimum angles for achieving strikes; accordingly, bowlers impart side rotation to ''hook'' (curve) the ball into the pins to increase the likelihood of striking. Oil is applied to approximately the first two-thirds of the lane's length to allow a "skid" area for the ball before it encounters friction and hooks. The oil is applied in different len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cocobolo
Cocobolo is a tropical hardwood of Central American trees belonging to the genus ''Dalbergia''. Only the heartwood of cocobolo is used; it is usually orange or reddish-brown, often with darker irregular traces weaving through the wood. The heartwood changes color after being cut and can be polished to a lustrous, glassy finish; being quite dense, sometimes having a specific gravity of over 1.0, it will sink in water. The sapwood (not often used) is a creamy yellow, with a sharp boundary between it and the heartwood. Provenance Cocobolo is yielded by two to four closely related species of the genus ''Dalbergia'', of which the best known is '' Dalbergia retusa'', a fair-sized tree, reported to reach in height and in diameter; it probably is the species contributing most of the wood in the trade. Because of the high value of the timber, the trees yielding it have been heavily exploited, so they have become rare outside of national parks, reserves, and plantations. Only relatively s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Makassar Ebony
''Diospyros celebica'' (commonly known as black ebony or Makassar ebony) is a species of Flowering plant, flowering tree in the family Ebenaceae that is Endemism, endemic to the island of Sulawesi in Indonesia. The common name Makassar ebony is for the main seaport on the island, Makassar. Makassar ebony wood is variegated, streaky brown and black, and nearly always wide-striped. It is considered a highly valuable wood for turnery, fine cabinet work, and Joinery (woodworking), joinery, and is much sought for posts () in traditional Japanese houses. Japan used to be the main importer of this wood. It is also used as a wood in fingerboards for guitars and other related instruments. The tree grows up to high under favourable circumstances, although such trees are rarely seen nowadays. Since Makassar ebony has been a woodworkers' favourite for centuries, most of it has been felled and used in high-quality furniture. The wood is often defective, showing cracks, and in particular h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosewood
Rosewood refers to any of a number of richly hued timbers, often brownish with darker veining, but found in many different hues. True rosewoods All genuine rosewoods belong to the genus ''Dalbergia''. The pre-eminent rosewood appreciated in the Western world is the wood of '' Dalbergia nigra''. It is best known as "Brazilian rosewood", but also as "Bahia rosewood". This wood has a strong, sweet smell, which persists for many years, explaining the name ''rosewood''. Another classic rosewood comes from '' Dalbergia latifolia'', known as (East) Indian rosewood or ''sonokeling'' (Indonesia). It is native to India and is also grown in plantations elsewhere in Pakistan (Chiniot). Madagascar rosewood ('' Dalbergia maritima''), known as ''bois de rose'', is highly prized for its red color. It is overexploited in the wild, despite a 2010 moratorium on trade and illegal logging, which continues on a large scale. Throughout southeast Asia, '' Dalbergia oliveri'' is harvested for us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vascular
Blood vessels are the structures of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away from the tissues. Blood vessels are needed to sustain life, because all of the body's tissues rely on their functionality. There are five types of blood vessels: the arteries, which carry the blood away from the heart; the arterioles; the capillaries, where the exchange of water and chemicals between the blood and the tissues occurs; the venules; and the veins, which carry blood from the capillaries back towards the heart. The word ''vascular'', meaning relating to the blood vessels, is derived from the Latin ''vas'', meaning vessel. Some structures – such as cartilage, the epithelium, and the lens and cornea of the eye – do not contain blood vessels and are labeled ''avascular''. Etymology * artery: late Middle English; from Latin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acne Mechanica
Acne mechanica is an acneiform eruption that has been observed after repetitive physical trauma to the skin such as rubbing, occurring from clothing (belts and straps) or sports equipment (football helmets and shoulder pads).Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). Page 685. McGraw-Hill. . In addition to those mechanisms, the skin not getting enough exposure to air also contributes to the formation of acne mechanica. It is often mistaken as a rash that forms on sweaty skin that is constantly being rubbed, but in reality, it is a breakout of acne mechanica. The term "acne" itself describes the occurrence in which hair follicles (also known as pores) in the skin get clogged by oil, dead skin cells, dirt and bacteria, or cosmetic products and create a pimple. Pimples can vary in type, size, and shape, but the sole basis of them occurring is the same - the oil gland in the pore becomes clogged and sometimes infected, which creates pus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperhidrosis
Hyperhidrosis is a condition characterized by abnormally increased sweating, in excess of that required for regulation of body temperature. Although primarily a benign physical burden, hyperhidrosis can deteriorate quality of life from a psychological, emotional, and social perspective. In fact, hyperhidrosis almost always leads to psychological as well as physical and social consequences. It is thus responsible for more than ¼ of the cases of social phobia. Patients suffering from it present difficulties in the professional field, more than 80% of patients experience a moderate to severe emotional impact from the disease and half are subject to depression. This excess of sweat happens even if the person is not engaging in tasks that require muscular effort, and it does not depend on the exposure to heat. Common places to sweat can include underarms, face, neck, back, groin, feet, and hands. It has been called by some researchers 'the silent handicap'. Both '' diaphoresis'' and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiddler
A fiddle is a bowed string musical instrument, most often a violin. It is a colloquial term for the violin, used by players in all genres, including classical music. Although in many cases violins and fiddles are essentially synonymous, the style of the music played may determine specific construction differences between fiddles and classical violins. For example, fiddles may optionally be set up with a bridge with a flatter arch to reduce the range of bow-arm motion needed for techniques such as the double shuffle, a form of bariolage involving rapid alternation between pairs of adjacent strings. To produce a "brighter" tone than the deep tones of gut or synthetic core strings, fiddlers often use steel strings. The fiddle is part of many traditional (folk) styles, which are typically aural traditions—taught " by ear" rather than via written music. Fiddling is the act of playing the fiddle, and fiddlers are musicians that play it. Among musical styles, fiddling tends to pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wear
Wear is the damaging, gradual removal or deformation of material at solid surfaces. Causes of wear can be mechanical (e.g., erosion) or chemical (e.g., corrosion). The study of wear and related processes is referred to as tribology. Wear in machine elements, together with other processes such as fatigue and creep, causes functional surfaces to degrade, eventually leading to material failure or loss of functionality. Thus, wear has large economic relevance as first outlined in the Jost Report. Abrasive wear alone has been estimated to cost 1-4% of the gross national product of industrialized nations. Wear of metals occurs by plastic displacement of surface and near-surface material and by detachment of particles that form wear debris. The particle size may vary from millimeters to nanometers. This process may occur by contact with other metals, nonmetallic solids, flowing liquids, solid particles or liquid droplets entrained in flowing gasses. The wear rate is affected by f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
