Rabu, 27 Oktober 2010

Anklet

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Anklet and toe ring
A toe ring with attached anklet
An anklet (in Arabic: خلخال), ankle chain, or ankle bracelet is an ornament worn around the ankle. Barefoot anklets and toe rings historically have been worn for centuries by girls and women in Egypt and Arab world especially in Bedouin and countryside and married women in India, though in the United States both casual and more formal anklets became fashionable in the late twentieth century. While in western popular culture both younger men and women may wear casual leather anklets, they are popular among barefoot women. Formal anklets (silver, gold, beads) are common women's fashion jewelry.[citation needed] Anklets are an important jewellery in Indian marriages worn along with saris.
Much more rarely, the ankle chains are joined by a stretch of chain to limit the step. This practice was once more prevalent in the Middle East, where the effect was to give a 'feminine' short tripping step. Today a few western women follow this practice, but rarely in public. Very few people even have 'permanent', e.g. soldered-on, ankle chains, and more rarely still, so is the connecting chain.
History
Bronze anklets are visible as early as the Bronze Age in temperate Europe, in an area roughly along the Danube, in the Alpine foreland, up the Rhine to the Atlantic, and also down the Rhône (Sherratt, 2001). These were found among hoards in these areas, along with other bronze items characteristic of this time (c. 1800 BCE onwards), and are attributable to the Tumulus culture that spread across this region.
A first-century CE epic of Tamil literature called Cilappatikaram ("The story of the anklet") dealt with a woman whose husband was killed while trying to sell one of her anklets to a dishonest goldsmith. The anklets are described in great detail in the poem.
As an ornament
Anklets can be made of silver, gold, and other less precious metals as well as leather, plastic, nylon and other such materials. In the western world anklets or ankle chains are mainly worn by younger females, but some older women also wear them.
Metal anklets are of two types - flexible and inflexible. The flexible ones, often called paayal, pajeb or jhanjhar in India, are made by tying links in a chain. Subsequently, sonorous bells can be attached to the chain, so that the wearer can make pleasing sounds while walking. Inflexible ones are usually created by giving shape to a flat metal sheet.

Ghungroo

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A pair of ghungroos
A ghungroo, ghunghroo or ghunghru is one of many small metallic bells strung together to form ghungroos, a musical anklet tied to the feet of classical Indian dancers.[1] The sounds produced by ghungroos vary greatly in pitch depending on their metallic composition and size. Ghungroos serve to accentuate the rhythmic aspects of the dance and allow complex footwork to be heard by the audience. They are worn immediately above the ankle, resting on the lateral malleolus and medial malleolus. A string of ghungroos can range from 50 to greater than 200 bells knotted together. A novice child dancer may start with 50 and slowly add more as he or she grows older and advances in his or her technical ability. Ghungroos are worn in traditional performances of the classical Indian dance forms: bharatnatyam, kathak, kuchipudi, and odissi.
"Ghungroo" is also the name of the annual undergraduate cultural production of the South Asian Association at Harvard College.
Meena Kumari in Pakeezah wore ghungroo to perform her many mujra (classical dances). Madhubala in Mughal-E-Azam wore ghungroo in her song "Jab Pyar Kiya Toh Darna Kya" (If I Have Loved Why Should I Be Frightened). Vidya Balan danced to "Ami Je Tomar" (I Am Yours) in Bhool Bhulaiya.

Diving weighting system

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A bag weight belt and a traditional weight belt
Divers wear weighting systems, weight belts or weights, generally made of lead, to counteract the buoyancy of other diving equipment, such as diving suits and aluminium diving cylinders.
Providing the weights have a method of quick release, they provide a useful rescue mechanism: they can be dropped in an emergency to provide instant buoyancy which may return the diver to the surface. Dropping weights increases the risk of barotrauma and decompression sickness due to uncontrollable ascent to the surface. This risk can only be justified when the emergency is life threatening. Very often divers take great care to ensure the weights are not dropped accidentally, and many heavily-weighted divers arrange their weights so subsets of the total weight can be dropped individually, allowing for a somewhat more controlled emergency ascent.
The quantity of lead weight required is determined by the overall positive buoyancy of the diver, which depends on the diver's body composition, buoyancy of other diving gear worn (especially the diving suit), water salinity, and water temperature. It normally is in the range of 2 kg / 4 pounds to 15 kg / 33 pounds.
The weights are generally made of lead because of its high density, low cost, and resistance to corrosion. The lead can be cast in blocks, cast block with gaps for straps or shaped as pellets often named "shot".
Weight belt
Weight belts are the most common weighting system currently in use of recreational diving.[1] Weight belts are often made of tough nylon, but other materials such as rubber can be used. Weight belts are generally fitted with a quick release buckle to allow the dumping of weight rapidly in an emergency.
A belt made of rubber is called a Marseillaise belt. These belts are popular with freedivers as the rubber contracts on descent as the diving suit and lungs are compressed, keeping the belt tight throughout the dive.[2]
The most common design of weight used with a belt consists of plain, rectangular lead blocks with two slits in them threaded onto the belt. These blocks can be coated in plastic, which further increases corrosion resistance. These weights are often marketed as being less abrasive to wetsuits.
Some weightbelts contain pouches to contain lead weights or round lead shot: this system allows the diver to add or remove weight more easily than with weights threaded onto the belt. The use of shot can also be more comfortable, as the shot moulds to the diver's body. Weight belts using shot are called shot belts. Each shot pellet should be coated to prevent corrosion by sea water, as use of uncoated shotgun shot here for sea diving would result in the lead corroding into powdery lead chloride.
BCD Integrated weights
These are stored in pockets built-in to the buoyancy control device. Often a velcro flap holds the weights in place. The weights may also be contained in zippered or velcroed pouches that slot into special pockets in the BCD. They have handles, which must be pulled to drop the weights in an emergency or to remove the weights when exiting the water. Some designs also have smaller "trim pouches" located higher in the BCD, which may help the diver maintain neutral attitude in the water. Trim pouches typically can not be ditched quickly, and are designed to hold only 1-2 pounds (0.5-1 Kilo) each. Many integrated systems cannot carry as much weight as a separate weight belt: a typical capacity is 6 kg per pocket, with two pockets available.[3]
Weight harness
A weight harness consists of a belt around the waist holding pouches for the weights with shoulder straps for extra support and security. Often a velcro flap holds the weights in place. They have handles, which must be pulled to drop the weights in an emergency or to remove the weights when exiting the water.
Fixed weights
In addition to the weight that can be dropped easily ('ditched'), some divers add additional fixed weights to their gear, either to reduce the weight placed on the belt, which can cause lower back pain, or to shift the diver's center of mass to achieve the optimum position in the water.
  • Tank weights are attached to the diving cylinder to shift the center of mass backward and upward or downward, depending on placement.
  • Ankle weights, which are typically 1 lb./0.5 kg of shot, are used to counteract the positive buoyancy of diving suit leggings, made worse in drysuits by the migration of the internal bubble of air to the feet, and positively buoyant fins. Some divers prefer negatively buoyant fins. The additional effort needed when finning with ankle weights increases the diver's gas consumption.
  • Metal backplates made from stainless steel, which may be used in some Buoyancy compensators, move the center of mass upward and backward.
  • Steel dive cylinders are preferred over aluminium cylinders by some divers—particularly cold water divers who must wear a suit that increases their overall buoyancy—because of their negative buoyancy, and because they shift mass upward and backward. Most steel tanks stay negatively buoyant regardless of whether they are full or empty, aluminium tanks become positively buoyant as the gas they contain is used.

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