A contact lens (also known as a "contact") is a corrective, cosmetic, or sometimes protective lens located on the cornea of the eye.
Contact lenses are obtainable in a number of varieties, including hard and soft. Hard contacts are classically not disposable, while soft contacts often are. Some soft contacts are also well-known as extended wear lenses. Contact lenses (both soft and hard) are made a variety of types of polymers, the latest containing some variant of silicone hydrogel. Previously, hard contact lenses were made of a polymer known as PMMA. They have since been replaced by rigid gas-permeable (RGP) contact lenses. Many contact lenses are made of hydrophilic (water-absorbing) materials, thereby allowing oxygen to reach the cornea, and make the lens more comfortable to wear.
Heavily tinted contacts are tinted to change the color of the iris, and are used for cosmetic reasons. Some standard contact lenses are somewhat tinted in order to make them more visible for handling purposes.
Thursday, March 29, 2007
Monday, March 26, 2007
Clock
A clock is an instrument for measuring time.Those used for technical purposes, of extremely high accuracy, are sometimes called chronometers. A portable clock is called a watch. The clock in its most common modern form displays the hours, minutes, and sometimes seconds that pass over a twelve or twenty-four-hour period.
The world's first self-striking clock was said to be invented by Chang Yeong-Sil, a chief enginner of Korea, in Korea during the Joseon Dynasty. It was called Chagyongru, which means "self-striking clock" in Korean
The development of electronics in the twentieth century led to clocks with no clockwork parts at all. Time in these cases is measured in several ways, such as by the behaviour of quartz crystals, or the decay of radioactive elements. Even mechanical clocks contain since come to be largely powered by batteries, removing the need for winding.
The world's first self-striking clock was said to be invented by Chang Yeong-Sil, a chief enginner of Korea, in Korea during the Joseon Dynasty. It was called Chagyongru, which means "self-striking clock" in Korean
The development of electronics in the twentieth century led to clocks with no clockwork parts at all. Time in these cases is measured in several ways, such as by the behaviour of quartz crystals, or the decay of radioactive elements. Even mechanical clocks contain since come to be largely powered by batteries, removing the need for winding.
Wednesday, March 21, 2007
Spacecraft propulsion
Spacecraft propulsion is used to modify the velocity of spacecraft and artificial satellites, or in short, to provide delta-v. There are many dissimilar methods. Each method has drawbacks and advantages, and spacecraft propulsion is an active area of research. Most spacecraft today are propelled by heating the reaction mass and allowing it to flow out the back of the vehicle. This sort of engine is called a rocket engine.
All current spacecraft use chemical rocket engines for launch, though some have used air-breathing engines on their first stage. Most satellites have simple reliable chemical rockets (often monopropellant rockets) or resistojet rockets to keep their station, although some use momentum wheels for attitude control. Newer geo-orbiting spacecraft are initial to use electric propulsion for north-south stationkeeping. Interplanetary vehicles mostly use chemical rockets as well, though a few have experimentally used ion thrusters with some success
All current spacecraft use chemical rocket engines for launch, though some have used air-breathing engines on their first stage. Most satellites have simple reliable chemical rockets (often monopropellant rockets) or resistojet rockets to keep their station, although some use momentum wheels for attitude control. Newer geo-orbiting spacecraft are initial to use electric propulsion for north-south stationkeeping. Interplanetary vehicles mostly use chemical rockets as well, though a few have experimentally used ion thrusters with some success
Friday, March 16, 2007
American White Pelican
The American White Pelican (Pelecanus erythrorhynchos) is a very large (50"–70") white bird with black wing tips and an huge orange bill. They have a wing span of approximately 3 m . They are elegant in flight, moving their wings in slow powerful strokes.
Unlike the Brown Pelican, the American White Pelican does not dive for its food. Instead it practices helpful fishing. Each bird eats more than 4 pounds of fish a day, mostly carp, chubs, shiners, perch, catfish, and jackfish.
White Pelicans nest in colonies of a number of hundred pairs on islands in remote brackish and freshwater lakes of inland North America. The female lays 2 or 3 eggs in a shallow depression on the ground. Both parents incubate.
An American White Pelican at Edinburgh Zoo.
Visible on the bill are the remains of a protrusion grown throughout breeding season.They winter in central California and along the Pacific coast of Guatemala; also along the shores of the Gulf of Mexico.
Shooting by poachers is the main known cause of mortality. Colonies are responsive to disturbance and visits by humans can cause the pelicans to leave and abandon their nests.
This species is protected by the Migratory Bird Treaty of 1972.
The scientific name for this species combines Pelecanus, the Latin for pelican, with erythrorhynchos, derived from the Greek words erythros meaning red, and rhynchos meaning beak.
Unlike the Brown Pelican, the American White Pelican does not dive for its food. Instead it practices helpful fishing. Each bird eats more than 4 pounds of fish a day, mostly carp, chubs, shiners, perch, catfish, and jackfish.
White Pelicans nest in colonies of a number of hundred pairs on islands in remote brackish and freshwater lakes of inland North America. The female lays 2 or 3 eggs in a shallow depression on the ground. Both parents incubate.
An American White Pelican at Edinburgh Zoo.
Visible on the bill are the remains of a protrusion grown throughout breeding season.They winter in central California and along the Pacific coast of Guatemala; also along the shores of the Gulf of Mexico.
Shooting by poachers is the main known cause of mortality. Colonies are responsive to disturbance and visits by humans can cause the pelicans to leave and abandon their nests.
This species is protected by the Migratory Bird Treaty of 1972.
The scientific name for this species combines Pelecanus, the Latin for pelican, with erythrorhynchos, derived from the Greek words erythros meaning red, and rhynchos meaning beak.
Sunday, March 11, 2007
Spider silk
Spider silk is a fibre secreted by spiders. Spider silk is a remarkably physically powerful material. Its tensile strength is similar to that of high-grade steel — according to Nature , spider silk has a tensile strength of approximately 1.3 GPa, while one source lists a tensile strength for one form of steel at 1.65 GPa. However, spider silk is much less dense than steel; its ratio of tensile strength to density is perhaps 5 times better than steel — as strong as Aramid filaments, such as Twaron or Kevlar. In fact, a strand of spider silk long sufficient to circle the earth would weigh less than 16 ounces (less than 460 grams).
Spiders usually use their silk to make structures, either for protection for their offspring, or for predation on other creatures. They can also suspend themselves using their silk, in general for the same reasons.
The Trapdoor spider will burrow into the ground and weave a trapdoor-like structure with spindles around so it can tell when prey arrives and take it by surprise.
Many small spiders use silk threads for ballooning. They extrude several threads into the air and let themselves become carried away with upward winds. Although most rides will end a few meters later, it seems to be a ordinary way for spiders to invade islands. Many sailors have reported that spiders have been caught in their ship's sails, even when far from land.
Spiders usually use their silk to make structures, either for protection for their offspring, or for predation on other creatures. They can also suspend themselves using their silk, in general for the same reasons.
The Trapdoor spider will burrow into the ground and weave a trapdoor-like structure with spindles around so it can tell when prey arrives and take it by surprise.
Many small spiders use silk threads for ballooning. They extrude several threads into the air and let themselves become carried away with upward winds. Although most rides will end a few meters later, it seems to be a ordinary way for spiders to invade islands. Many sailors have reported that spiders have been caught in their ship's sails, even when far from land.
Tuesday, March 06, 2007
Kite fishing
Kite fishing is supposed to have been first invented in China. It was, and is, also used by the people of New Guinea and other Pacific Islands - either by cultural distribution from China or independent invention.
Kites can give the boatless fishermen access to waters that would otherwise be available only to boats. Similarly, for boat owners, kites provide a way to fish in areas where it is not safe to find the way such as shallows or coral reefs where fish may be plentiful. Kites can also be used for trolling a lure through the water.
Suitable kites may be of very easy construction. Those of Tobi Island are a large leaf stiffened by the ribs of the fronds of the coconut palm. The fishing line may be made from coconut fibre and the lure made from spiders webs.
Modern kitefishing is popular in New Zealand, where large delta kites of synthetic materials are used to fish from beaches, taking a line and hooks far out past the breakers. Kite fishing is also emerging in Melbourne where sled kites are becoming well-liked, both off beaches and off boats and in freshwater areas. link title The disabled community are ever more using the kites for fishing as they allow mobility impaired people to cast the bait further out than they would otherwise be able to.
Kites can give the boatless fishermen access to waters that would otherwise be available only to boats. Similarly, for boat owners, kites provide a way to fish in areas where it is not safe to find the way such as shallows or coral reefs where fish may be plentiful. Kites can also be used for trolling a lure through the water.
Suitable kites may be of very easy construction. Those of Tobi Island are a large leaf stiffened by the ribs of the fronds of the coconut palm. The fishing line may be made from coconut fibre and the lure made from spiders webs.
Modern kitefishing is popular in New Zealand, where large delta kites of synthetic materials are used to fish from beaches, taking a line and hooks far out past the breakers. Kite fishing is also emerging in Melbourne where sled kites are becoming well-liked, both off beaches and off boats and in freshwater areas. link title The disabled community are ever more using the kites for fishing as they allow mobility impaired people to cast the bait further out than they would otherwise be able to.
Thursday, March 01, 2007
Giant panda
The giant panda (Ailuropoda melanoleuca) ("black-and-white cat-foot") is a mammal classified in the bear family, Ursidae, native to central and southern China.It is easily known by its large, distinctive black patches around the eyes, ears and on its rotund body. Though technically a carnivore, the panda has a diet which is 98% bamboo. However, they may eat other foods such as honey, eggs, fish, and yams.
The Giant Panda is an endangered animal; an estimated 3,000 pandas live in the wildand some 221 were reported to live in captivity at the end of 2006 in China,with twenty pandas living outside of China. However, reports show that the numbers of wild panda are on the rise.The giant panda has long been a most wanted of the public, at least partly on account of the fact that the species has an appealing baby-like cuteness that makes it seem to resemble a living teddy bear. The fact that it is regularly depicted reclining peacefully eating bamboo, as opposed to hunting, also adds to its image of innocence. Though the giant panda is often assumed docile because of their cuteness, they have been known to attack humans, usually assumed to be out of irritation rather than predatory behavior.
The Giant Panda is an endangered animal; an estimated 3,000 pandas live in the wildand some 221 were reported to live in captivity at the end of 2006 in China,with twenty pandas living outside of China. However, reports show that the numbers of wild panda are on the rise.The giant panda has long been a most wanted of the public, at least partly on account of the fact that the species has an appealing baby-like cuteness that makes it seem to resemble a living teddy bear. The fact that it is regularly depicted reclining peacefully eating bamboo, as opposed to hunting, also adds to its image of innocence. Though the giant panda is often assumed docile because of their cuteness, they have been known to attack humans, usually assumed to be out of irritation rather than predatory behavior.
Sunday, February 25, 2007
Cast iron
Cast iron generally refers to grey cast iron, but can mean any of a group of iron-based alloys containing more than 2% carbon. It is made by remelting pig iron, often along with substantial quantities of scrap iron and scrap steel, and taking a variety of steps to remove undesirable contaminants such as phosphorus and sulfur. Carbon and silicon content are reduced to the desired levels, which may be anywhere from 2% to 3.5% for carbon and 1% to 3% for silicon depending on the application. Other elements are then added to the melt before the final form is shaped by casting.
Iron is most commonly melted in a small blast furnace known as a cupola. After melting is complete, the molten iron is removed or ladled from the forehearth of the blast furnace. This process is thought to have been devised by the late 18th century ironmaster John Wilkinson, whose innovative ideas revolutionized the field of metallurgy. Previously, iron was melted in an air furnace, which is a type of reverberatory furnace.
Iron is most commonly melted in a small blast furnace known as a cupola. After melting is complete, the molten iron is removed or ladled from the forehearth of the blast furnace. This process is thought to have been devised by the late 18th century ironmaster John Wilkinson, whose innovative ideas revolutionized the field of metallurgy. Previously, iron was melted in an air furnace, which is a type of reverberatory furnace.
Tuesday, February 20, 2007
Classification of Tamil
Tamil is associate of the Tamil language family, which includes the Irula, Kaikadi, Betta Kurumba, Sholaga, and Yerukula languages. This group is a subgroup of the Tamil-Malayalam languages, which falls under a subgroup of the Tamil-Kodagu languages, which in turn is a subgroup of the Tamil-Kannada languages. The Tamil-Kannada languages belong to the southern branch of the Dravidian language family. Tamil is most directly related to Malayalam, spoken in the Indian state of Kerala which borders Tamil Nadu. Linguists estimate Malayalam divided from Tamil between the 8th and 10th centuries.
Wednesday, February 14, 2007
Ice cream
Before the growth of modern refrigeration, ice cream was a luxury item kept for special occasions. Making ice cream was quite difficult. Ice was cut commercially from lakes and ponds during the winter and stored in large heaps in holes in the ground or in wood-frame ice houses, insulated by straw. Ice cream was made by hand in a huge bowl enclosed by packed ice and salt. The temperature of the ingredients was reduced by the mix of compressed ice and salt. The salt water was chilled by the ice, and the action of the salt on the ice causes it to (partially) melt, absorbing latent heat bringing the combination below the freezing point of pure water. The wrapped up container can also make better thermal contact with the salty water and ice mixture than it could with ice alone.The hand-cranked churn, which still used ice and salt for cooling, was made-up by an American named Nancy Johnson in 1846, making invention possible on site and avoiding the problem of nonstop chilling between production and consumer. Ice cream became a trendy item for the first time. The world's first business ice cream factory was opened in Baltimore, Maryland in 1851, by Jacob Fussell, a dairy farmer. An unstable demand for his milk led him to mass create ice cream. This allowed the previously expensive invention to be offered in the city at reduced prices.Fussell opened ice cream parlors as far west as Texas. Many were still around well into the twentieth century. Fussell later sold his business to Borden.
The improvement of industrial refrigeration by German engineer Carl von Linde during the 1870s eliminated the need to cut and store natural ice and when the continuous-process freezer was perfected in 1926, allowed commercial mass invention of ice cream and the birth of the modern ice cream industry.The most common method for producing ice cream at home is to use an ice cream maker, in modern times normally an electrical device that churns the ice cream mixture while cooled inside a house freezer, or using ice and salt. A newer method of making home-made ice cream is to add liquid nitrogen to the mixture while moving it using a spoon or spatula.
The improvement of industrial refrigeration by German engineer Carl von Linde during the 1870s eliminated the need to cut and store natural ice and when the continuous-process freezer was perfected in 1926, allowed commercial mass invention of ice cream and the birth of the modern ice cream industry.The most common method for producing ice cream at home is to use an ice cream maker, in modern times normally an electrical device that churns the ice cream mixture while cooled inside a house freezer, or using ice and salt. A newer method of making home-made ice cream is to add liquid nitrogen to the mixture while moving it using a spoon or spatula.
Sunday, February 11, 2007
Diamond
Diamonds do not show all of their attractiveness as rough stones; instead, they must be cut and polished to exhibit the characteristic fire and intensity that diamond gemstones are known for. Diamonds are cut into a variety of shapes that are commonly designed to accentuate these features.Diamonds which are not cut to the specifications of round brilliant shape (or subsequent variations) are known as "fancy cuts." Popular fancy cuts include the baguette (from the French, meaning rod or loaf of bread), marquise, princess (square outline), heart, briolette (a form of the rose cut), and pear cuts. Newer cuts that have been introduced into the jewelry industry are the "cushion" "radiant"(similar to princess cuts, but with rounded edges instead of square edges) and "Asscher" cuts. Many fancy colored diamonds are now being cut according to these new styles. Generally speaking, these "fancy cuts" are not held to the same strict standards as Tolkowsky-derived round brilliants and there are less specific mathematical guidelines of angles which determine a well-cut stone. Cuts are influenced heavily by fashion: the baguette cut—which accentuates a diamond's luster and downplays its fire—was all the rage during the Art Deco period, whereas the princess cut—which accentuates a diamond's fire rather than its luster—is currently gaining popularity. The princess cut is also popular amongst diamond cutters: of all the cuts, it wastes the least of the original crystal. The past decades have seen the development of new diamond cuts, often based on a modification of an existing cut. Some of these include extra facets. These newly developed cuts are viewed by many as more of an attempt at brand differentiation by diamond sellers, than actual improvements to the state of the art
Monday, February 05, 2007
Software
Software basically is the distinct image or representation of physical or material position that constitute configuration to or functional identity of a machine, usually a computer. As a substance of memory, software in principle can be changed without the alteration to the static paradigm of the hardware thus without the remanufacturing thereof. generally software is of an algorithmic form which translates into being to a progression of machine instructions. Some software, however, is of a relational form which translate into being the map of a recognition network.
Software is a program that enables a computer to achieve a specific task, as contrasting to the physical components of the system (hardware). This include application software such as a word processor, which enables a user to achieve a task, and system software such as an operating system, which enables other software to run suitably, by interfacing with hardware and with other software.
The term "software" was first used in this intellect by John W. Tukey in 1957. In computer science and software engineering, computer software is all computer program. The perception of reading different sequences of instructions into the memory of a apparatus to control computations was invented by Charles Babbage as part of his difference engine. The theory that is the source for most modern software was first projected by Alan Turing in his 1935 essay Computable numbers with an application to the Entscheidungs problem.
Types
Practical computer systems partition software into three major classes: system software, programming software and application software, although the division is subjective, and often blurred.
* System software is one of the major class helps run the computer hardware and computer system. It includes working systems, device drivers, analytical tools, servers, windowing systems, utilities and more. The intention of systems software is to protect the applications programmer as much as possible from the details of theexacting computer complex being use, especially memory and other hardware features, and such accessory procedure as communications, printers, readers, displays, keyboards, etc.
* Programming software usually provide tools to support a programmer in writing computer programs and software with different programming languages in a more suitable way.The tools comprise text editors, compilers, interpreters, linkers, debuggers, and so on, An incorporated development environment (IDE) merge those tools into a software bundle, and a programmer may not need to type various command for compiling, interpreter, debugging, tracing, and etc., because the IDE typically has an sophisticated graphical user interface, or GUI.
* Application software allows humans to complete one or more explicit (non-computer related) tasks. typical applications include manufacturingautomation, business software, educational software, medical software, databases and computer games. Businesses are possibly the biggest users of application software, but approximately every field of human action now uses some form of application software. It is used tocomputerizeall sorts of functions.
Software is a program that enables a computer to achieve a specific task, as contrasting to the physical components of the system (hardware). This include application software such as a word processor, which enables a user to achieve a task, and system software such as an operating system, which enables other software to run suitably, by interfacing with hardware and with other software.
The term "software" was first used in this intellect by John W. Tukey in 1957. In computer science and software engineering, computer software is all computer program. The perception of reading different sequences of instructions into the memory of a apparatus to control computations was invented by Charles Babbage as part of his difference engine. The theory that is the source for most modern software was first projected by Alan Turing in his 1935 essay Computable numbers with an application to the Entscheidungs problem.
Types
Practical computer systems partition software into three major classes: system software, programming software and application software, although the division is subjective, and often blurred.
* System software is one of the major class helps run the computer hardware and computer system. It includes working systems, device drivers, analytical tools, servers, windowing systems, utilities and more. The intention of systems software is to protect the applications programmer as much as possible from the details of theexacting computer complex being use, especially memory and other hardware features, and such accessory procedure as communications, printers, readers, displays, keyboards, etc.
* Programming software usually provide tools to support a programmer in writing computer programs and software with different programming languages in a more suitable way.The tools comprise text editors, compilers, interpreters, linkers, debuggers, and so on, An incorporated development environment (IDE) merge those tools into a software bundle, and a programmer may not need to type various command for compiling, interpreter, debugging, tracing, and etc., because the IDE typically has an sophisticated graphical user interface, or GUI.
* Application software allows humans to complete one or more explicit (non-computer related) tasks. typical applications include manufacturingautomation, business software, educational software, medical software, databases and computer games. Businesses are possibly the biggest users of application software, but approximately every field of human action now uses some form of application software. It is used tocomputerizeall sorts of functions.
Friday, January 26, 2007
Journalism Basics
Journalism is a concrete, professionally oriented major that involves gathering, interpreting, distilling, and other reporting information to the general audiences through a variety of media means. Journalism majors learn about every possible kind of Journalism (including magazine, newspaper, online journalism, photojournalism, broadcast journalism, and public relations).
That's not all, though. In addition to dedicated training in writing, editing, and reporting, Journalism wants a working knowledge of history, culture, and current events. You'll more than likely be required to take up a broad range of courses that runs the range from statistics to the hard sciences to economics to history. There would also be a lot of haughty talk about professional ethics and civic responsibility too - and you'll be tested on it. To top it all off, you'll perhaps work on the university newspaper or radio station, or possibly complete an internship with a magazine or a mass media conglomerate.
That's not all, though. In addition to dedicated training in writing, editing, and reporting, Journalism wants a working knowledge of history, culture, and current events. You'll more than likely be required to take up a broad range of courses that runs the range from statistics to the hard sciences to economics to history. There would also be a lot of haughty talk about professional ethics and civic responsibility too - and you'll be tested on it. To top it all off, you'll perhaps work on the university newspaper or radio station, or possibly complete an internship with a magazine or a mass media conglomerate.
Wednesday, December 27, 2006
Plants
The genus Nelumbo, with two members Indian, Red or Sacred Lotus, a sacred plant of Hinduism and Buddhism and of the Ancient Egyptian civilization, also used in Asian cuisine American Lotus The genus Lotus, in the subfamily Faboideae in the family Fabaceae, common name "Trefoil" The genus Nymphaea, usually called water-lilies, but including many members also referred to as lotus, for example the White European Lotus, White Egyptian Lotus, and Blue Egyptian Lotus.The lotus eaten by the Lotophagi of the Odyssey is thought to have been Ziziphus lotus, a species of jujube. This could be the Lotus Tree that the mythical Lois was transformed into "Lotus" also occurs in the common, or cultivar, names of numerous unrelated plants, for example the Snow Lotus in the family Asteraceae.
Monday, December 18, 2006
Socialism and social democracy
The term socialism, used from the 1830s onwards in France and England, was directly related to what was called the social question, in essence the problem that the emergence of competitive market societies did not create liberty, equality and fraternity for all citizens, requiring the intervention of politics and social reform to tackle social problems, injustices and grievances a topic on which Jean-Jacques Rousseau discourses at length in his classic work The Social Contract. Originally the term socialist was often used interchangeably with co-operative, mutuality, associations and collectivist.
The term social democracy originally referred to the political project of extending democratic forms of association to the whole of society, substituting popular sovereignty, the universal franchise and social ownership for the rule of a propertied class which had exclusive voting rights.
The term social democracy originally referred to the political project of extending democratic forms of association to the whole of society, substituting popular sovereignty, the universal franchise and social ownership for the rule of a propertied class which had exclusive voting rights.
Thursday, December 07, 2006
Photography
Photography is the process of making pictures by means of the action of light. Light patterns reflected or emitted from objects are recorded onto a sensitive medium or storage chip through a timed exposure. The process is done through mechanical, chemical or digital devices known as cameras.
Lens and mounting of a large-format cameraWikibooks has more about this subject:
PhotographyThe word comes from the Greek words φως phos ("light"), and γραφις graphis ("stylus", "paintbrush") or γραφη graphê, together meaning "drawing with light" or "representation by means of lines" or "drawing." Traditionally the product of photography has been called a photograph. The term photo is an abbreviation; many people also call them pictures. In digital photography, the term image has begun to replace photograph.
Lens and mounting of a large-format cameraWikibooks has more about this subject:
PhotographyThe word comes from the Greek words φως phos ("light"), and γραφις graphis ("stylus", "paintbrush") or γραφη graphê, together meaning "drawing with light" or "representation by means of lines" or "drawing." Traditionally the product of photography has been called a photograph. The term photo is an abbreviation; many people also call them pictures. In digital photography, the term image has begun to replace photograph.
Tuesday, November 28, 2006
Peripheral layout
The very old city inside the walls covers about four percent of the current municipality's 582 square miles. The old city is the negligible of Rome's twelve administrative zones. The walled city center is made up of 22 ironies, nearby it is 35 quarter urbane, and within the city restrictions are six large suburbia. The commune of Rome positioned outside the municipal boundaries about doubles the area of the real city.
The belt highway known as Grande Record Annular describes an enormous circle around the wealth, about six miles out from the city centre; unlike most Italian highways, the G.R.A. is toll-free. The sphere ties together the antique roads to lead to Rome: the Via Famines, the Via Aurelia and Via Apia. Large amounts of modern dwelling buildings are located in the districts outside the centre, where current architecture has not gone unnoticed. Many road frontages and show windows often change to keep up with the times and the Romans have succeeded in harmonizing the old and the fresh.
The belt highway known as Grande Record Annular describes an enormous circle around the wealth, about six miles out from the city centre; unlike most Italian highways, the G.R.A. is toll-free. The sphere ties together the antique roads to lead to Rome: the Via Famines, the Via Aurelia and Via Apia. Large amounts of modern dwelling buildings are located in the districts outside the centre, where current architecture has not gone unnoticed. Many road frontages and show windows often change to keep up with the times and the Romans have succeeded in harmonizing the old and the fresh.
Friday, November 24, 2006
Hygiene
Hygiene is the maintenance of healthy practices. In modern terms, this is usually regarded as a particular orientation to cleanliness. The word Hygiene originates as a reference to Hygieia, who was a daughter of Asclepius and the deity of health, cleanliness and sanitation. The related term personal grooming means to improve one's physical appearance or appeal for others, by removing obvious imperfections in one's appearance or civilizing one's hygiene.
Outward signs of good hygiene take in the absence of visible dirt or of bad smells. Since the expansion of the germ theory of disease, hygiene has come to mean any perform leading to the absence of harmful levels of microorganisms.
Good hygiene is a support to health, beauty, comfort, and social interactions. It directly aids in disease prevention and disease segregation.
Washing is the most common instance of hygienic behavior. Washing is often done with soap or detergent which helps to eliminate oils and to break up dust particles so they may be washed away.
Tuesday, November 21, 2006
Clothing maintenance
Clothing, once manufactured, suffers physical bother both from within and from without. The human body inside sheds skin cells and body oils, and exudes sweat, urine, and feces. From the outside, sun damage, damp, abrasion, dirt, and other indignities afflict the garment. Bedbugs and lice take up residence in clothing seams. Well-worn clothing, if not cleaned and refurbished, will smell, itch, look shabby, and lose functionality.
In past times, restoration was an art. A careful tailor or seamstress could fix rips with thread raveled from hems and seam limits so skillfully that the darn was practically invisible. When the raw fabric cloth was worth more than labor, it made sense to use labor in saving it. Today clothing is considered a consumable item. Mass manufactured clothing is less expensive than the time it would take to repair it. Many people wish to buy a new piece of clothing rather than to waste their time mending old clothes. But the thrifty still replace zippers and buttons and stitch up ripped hems.
In past times, restoration was an art. A careful tailor or seamstress could fix rips with thread raveled from hems and seam limits so skillfully that the darn was practically invisible. When the raw fabric cloth was worth more than labor, it made sense to use labor in saving it. Today clothing is considered a consumable item. Mass manufactured clothing is less expensive than the time it would take to repair it. Many people wish to buy a new piece of clothing rather than to waste their time mending old clothes. But the thrifty still replace zippers and buttons and stitch up ripped hems.
Thursday, November 16, 2006
Lava composition
If the erupted molten rock contains a high percentage of silica, the lava is called felsic.
Felsic lavas tend to be extremely viscous and are erupted as domes or short, broad flows. Viscous lavas tend to form stratovolcanoes or lava domes. Lassen Peak in California is an example of a volcano created from felsic lava and is actually a large lava ground.
Because siliceous magmas are so sticky, they tend to catch volatiles that are present, which cause the magma to erupt catastrophically, eventually forming stratovolcanoes. Pyroclastic flows are extremely hazardous products of such volcanoes, since they are composed of molten volcanic ash too heavy to go up into the environment, so they hug the volcano's slopes and travel far from their vents during large eruptions. Temperatures as high as 1,200 °C are known to happen in pyroclastic flows, which will incinerate everything combustible in their path and thick layers of hot pyroclastic flow deposits can be laid down, often up to many meters thick.
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