Routing audio theory

[walters]

With the new rack mount effects u can route signals serial,parallel plus more
gets really confussing let me see if i can clear this up more

Lexicon
TC electronics
Digitech
Zoom
Behringer
Korg

They all have different routings names and configurations

outine:
1.) Stereo
2.) Stereo (wet only)
3.) mono (wet only)
4.) Mono input/ stereo output
5.) Cascade
6.) Dual Mono
7.) Dual Stereo (parallel)
8.) Mono Split
9.) Behringer has like 6 more parallel ones
and 4 more series ones with no names

Stereo
1.) The left and Right input "split" the Left Dry and Right Dry
2.) The Left input and Right input go to One processor chip ** the right and left channels don't get mixed
they go direct to the processor chip**
3.) Chip outputs a Left (wet) gets "Mixed" with the Left (dry) and Left (wet)
4.) chip outputs a Right (wet) gets Mixed with the Right (dry) and Right (wet)

Stereo (wet only)

1.) Left channel input goes direct to processor chip pin
2.) Right channel input goes direct to processor chip pin
3.) No dry signals , no splitting
4.) Chip outputs a Left Wet goes to a volume control then to Left output
5.) Chip outputs a Right wet goes to a volume control then to right output

Mono (wet only)

1.) Left channel input and Right channel inputs get summed and mixed together
2.) Both channels mixed go to the processor chip
3.) Chip outputs a Left channel wet and a Right channel wet seperate


Mono in/Stereo out

1.) Left channel and Right channel inputs "splits" dry signal goes to the output summing stage
2.) The left channel and right channel mixed the other dry signals together for the input summing stage
3.) Both channels are mixed/summed both go to processor chip
4.) Outputs both channel seperate
5.) The Left (wet) gets mixed/summed with left DRY
The Right(wet) gets mixed/summed with right dry


Cascade

1.) Left channel and Right channel go to seperate inputs into Processor chip #A
2.) Left channel and Right Channel go to seperate outputs of Block A
3.) Left channel and Right channel go to seperate inputs into Processor chip #B in series
4.) Left channel and Right Channel go to seperate outputs of Block B

Dual Mono

1.) Left channel splits but both signals go into Processor chip #A
2.) Processor chip outputs 2 signals but "merges" not sum's them to Left channel
3.) Right channel splits but both signals go into Processor chip #B
4.) Processor chip outputs 2 signals but "merges" not sum's them to Right channel

Mono Split

1.) Left channel splits but both signals go into Processor Chip#A
2.) Right Channel splits but both signals go into Processor chip#B
3.) Processor#A outputs 2 signals one goes to the Left channel output the other "splits" goes to the Right channel
4.) Processor#B outputs 2 signals one goes to the right channel output the other "splits" goes to the Left channel

Dual Stereo (Parallel)

1.) Left channel splits one signal goes to Processor chip#A the other signal goes to Processor chip #B
2.) Right channel splits one signal goes to Processor chip# B the other signal goes to Processor chip#A
3.) Outputs Left and Right crisscross plus have their own outputs for left and right channels


By The manual book:

Dual Mono
This routing option sends the Left and Right input signals through Effect 1/3 and
Effect 2/4 respectively. Each signal is then routed to its respective output, completely
independent from the other.
2. Cascade
Left and Right input signals are sent first through Effect 1/3, then through Effect 2/4,
then routed as a stereo signal to their respective outputs.
3. Parallel (Dual Stereo)
Left and Right input signals are sent through both effects independently. The output
signals of both Effects are then mixed together, and routed to both the outputs as a
single stereo signal.
4. Mono Split
Left input signal is sent through Effect 1/3, while the Right input signal is sent through
Effect 2/4. The output signals of both Effects are then mixed together, and routed to
both the outputs as a single stereo signal.
5. Stereo
Routing 5 provides a single stereo effect path for Left and Right signals. In the
Dual Stereo configuration, this routing utilizes all the DSP horsepower allocated
to the program, thus letting you use the expanded effects library used by the Stereo
Configuration programs. In Stereo programs, this routing removes one of the effect
modules allowing for users requiring a streamlined signal path with only a single
effect for their needs

1. Dual Mono
This routing option sends the Left and
Right input signals through Processor 1
and Processor 2 respectively. Each signal
is then routed to its respective output, completely
independent from the other.
2. Cascade
Left and Right input signals are sent first
through Processor 1, then through
Processor 2, then routed as a stereo signal
to their respective outputs.
3. Dual Stereo (Parallel)
Left and Right input signals are sent
through both processors independently.
The output signals of both processors are
then mixed together, and routed to both the
outputs as a single stereo signal.
4. Mono Split
Left input signal is sent through Processor
1, while the Right input signal is sent
through Processor 2. The output signals of
both processors are then mixed together,
and routed to both the outputs as a single
stereo signal.

 

[walters]

do u guys know any others routing or configurations?

 

[BigRay]

Go away walters. Quit your trolling nonsense. The people that know about your bullshit are avoiding you. Your joke is getting old. Please leave.

people, avoid this guy.

Walters, from now on, any thread you post will be bombarded with nonsense from me. I will cut and paste the dumbest things I can find(just like you do) until you go away.

 

[BigRay]

Rocket Principles

A consquence of Newton's laws of motion is that for any object, or collection of objects, forces which only involve those objects and nothing else ("internal forces") cannot shift the center of gravity. For example, an astronaut floating in a space suit cannot shift his position without involving something else, e. g. pushing against his spacecraft. The center of gravity--or "center of mass"--is a fixed point, which cannot be moved without outside help (turning around it, however, is possible).

By throwing a heavy tool in one direction, the astronaut could get moving in the opposite direction, though the common center of gravity of the two would always stay the same. Given a bottle of compressed oxygen, the same result follows from squirting out a blast of gas (a scene that appeared in an early science fiction film). A rocket does much the same, except that the cold gas is replaced by the much faster jet of glowing gas produced by the burning of suitable fuel. At present, rockets are the only means capable of achieving the altitude and velocity necessary to put a payload into orbit.

A rocket engine is a machine that develops thrust by the rapid expulsion of matter. Most rockets today operate with either solid or liquid propellants. The word propellant does not mean simply fuel, as you might think; it means both fuel and oxidizer. The fuel is the chemical rockets burn but, for burning to take place, an oxidizer (oxygen) must be present. Jet engines draw oxygen into their engines from the surrounding air. Rockets do not have the luxury that jet planes have; they must carry oxygen with them into space, where there is no air.

There are a number of terms used to describe the power generated by a rocket.

* Thrust is the force generated, measured in pounds or kilograms. Thrust generated by the first stage must be greater than the weight of the complete launch vehicle while standing on the launch pad in order to get it moving. Once moving upward, thrust must continue to be generated to accelerate the launch vehicle against the force of the Earth's gravity. To place a satellite into orbit around the Earth, thrust must continue until the minimum altitude and orbital velocity have been attained or the launch vehicle will fall back to the Earth. Minimum altitude is rarely desirable, therefore thrust must continue to be generated to gain additional orbital altitude.

* The impulse, sometimes called total impulse, is the product of thrust and the effective firing duration. A shoulder fired rocket has an average thrust of 600 lbs and a firing duration of 0.2 seconds for an impulse of 120 lb-sec. The Saturn V rocket, used during the Apollo program, not only generated much more thrust but also for a much longer time. It had an impulse of 1.15 billion lb-sec.

* The efficiency of a rocket engine is measured by its specific impulse (Isp). Specific impulse is defined as the thrust divided by the mass of propellant consumed per second. The result is expressed in seconds. The specific impulse can be thought of as the number of seconds that one pound of propellant will produce one pound of thrust. If thrust is expressed in pounds, a specific impulse of 300 seconds is considered good. Higher values are better. A rocket's mass ratio is defined as the total mass at lift-off divided by the mass remaining after all the propellant has been consumed. A high mass ratio means that more propellant is pushing less launch vehicle and payload mass, resulting in higher velocity. A high mass ratio is necessary to achieve the high velocities needed to put a payload into orbit.

There are three categories of chemical propellants for rocket engines: liquid propellant, solid propellant, and hybrid propellant. The propellant for a chemical rocket engine usually consists of a fuel and an oxidizer. Sometimes a catalyst is added to enhance the chemical reaction between the fuel and the oxidizer. Each category has advantages and disadvantages that make them best for certain applications and unsuitable for others.

Solid Propellant Rockets:

A solid-propellant rocket has the simplest form of engine. Solid propellant rockets are basically combustion chamber tubes packed with a propellant that contains both fuel and oxidizer blended together uniformly. It has a nozzle, a case, insulation, propellant, and an igniter. The case of the engine is usually a relatively thin metal that is lined with insulation to keep the propellant from burning through. The propellant itself is packed inside the insulation layer.

Solid rocket propellants, which are dry to the touch, contain both the fuel and oxidizer combined together in the chemical itself. Usually the fuel is a mixture of hydrogen compounds and carbon and the oxidizer is made up of oxygen compounds. The principal advantage is that a solid propellant is relatively stable therefore it can be manufactured and stored for future use. Solid propellants have a high density and can burn very fast. They are relatively insensitive to shock, vibration and acceleration. No propellant pumps are required thus the rocket engines are less complicated.

Disadvantages are that, once ignited, solid propellants cannot be throttled, turned off and then restarted because they burn until all the propellant is used. The surface area of the burning propellant is critical in determining the amount of thrust being generated. Cracks in the solid propellant increase the exposed surface area, thus the propellant burns faster than planned. If too many cracks develop, pressure inside the engine rises significantly and the rocket engine may explode. Manufacture of a solid propellant is an expensive, precision operation. Solid propellant rockets range in size from the Light Antitank Weapon to the 100 foot long Solid Rocket Boosters (SRBs) used on the side of the main fuel tank of the Space Shuttle.

Many solid-propellant rocket engines feature a hollow core that runs through the propellant. Rockets that do not have the hollow core must be ignited at the lower end of the propellants and burning proceeds gradually from one end of the rocket to the other. In all cases, only the surface of the propellant burns. However, to get higher thrust, the hollow core is used. This increases the surface of the propellants available for burning. The propellants burn from the inside out at a much higher rate, and the gases produced escape the engine at much higher speeds. This gives a greater thrust. Some propellant cores are star shaped to increase the burning surface even more.

To fire solid propellants, many kinds of igniters can be used. Fire-arrows were ignited by fuses, but sometimes these ignited too quickly and burned the rocketeer. A far safer and more reliable form of ignition used today is one that employs electricity. An example of an electrically fired rocket is the space shuttle's SRM. An electric current, coming through wires from some distance away, heats up a special wire inside the rocket. The wire raises the temperature of the propellant it is in contact with to the combustion point.

The nozzle in a solid-propellant engine is an opening at the back of the rocket that permits the hot expanding gases to escape. The narrow part of the nozzle is the throat. Just beyond the throat is the exit cone. The purpose of the nozzle is to increase the acceleration of the gases as they leave the rocket and thereby maximize the thrust. It does this by cutting down the opening through which the gases can escape.

To see how this works, you can experiment with a garden hose that has a spray nozzle attachment. This kind of nozzle does not have an exit cone, but that does not matter in the experiment. The important point about the nozzle is that the size of the opening can be varied. Start with the opening at its widest point. Watch how far the water squirts and feel the thrust produced by the departing water. Now reduce the diameter of the opening, and again note the distance the water squirts and feel the thrust. Rocket nozzles work the same way.

As with the inside of the rocket case, insulation is needed to protect the nozzle from the hot gases. The usual insulation is one that gradually erodes as the gas passes through. Small pieces of the insulation get very hot and break away from the nozzle. As they are blown away, heat is carried away with them.

Liquid Propellant Rockets:

The other main kind of rocket engine is one that uses liquid propellants. This is a much more complicated engine, as is evidenced by the fact that solid rocket engines were used for at least seven hundred years before the first successful liquid engine was tested. Liquid propellants have separate storage tanks - one for the fuel and one for the oxidizer. They also have pumps, a combustion chamber, and a nozzle. The fuel of a liquid-propellant rocket is usually kerosene or liquid hydrogen; the oxidizer is usually liquid oxygen. They are combined inside a cavity called the combustion chamber. High pressure turbopumps provide an example of the rocket engine. Here the propellants burn and build up high temperatures and pressures, and the expanding gas escapes through the nozzle at the lower end. To get the most power from the propellants, they must be mixed as completely as possible. Small injectors (nozzles) on the roof of the chamber spray and mix the propellants at the same time. Because the chamber operates under high pressures, the propellants need to be forced inside. Powerful, lightweight turbine pumps between the propellant tanks and combustion chambers take care of this job.

The major components of a chemical rocket assembly are a rocket motor or engine, propellant consisting of fuel and an oxidizer, a frame to hold the components, control systems and a cargo such as a satellite. A rocket differs from other engines in that it carries its fuel and oxidizer internally, therefore it will burn in the vacuum of space as well as within the Earth's atmosphere. The cargo is commonly referred to as the payload. A rocket is called a launch vehicle when it is used to launch a satellite or other payload into space. A rocket becomes a missile when the payload is a warhead and it is used as a weapon.

Many different types of rocket engines have been designed or proposed. Currently, the most powerful are the chemical propellant rocket engines. Other types being designed or that are proposed are ion rockets, photon rockets, magnetohydrodynamic drives and nuclear fission rockets; however, they are generally more suitable for providing long term thrust in space rather than launching a rocket and its payload from the Earth's surface into space.

A cryogenic propellant is one that uses very cold, liquefied gases as the fuel and the oxidizer. Liquid oxygen boils at -297 F and liquid hydrogen boils at -423 F. Cryogenic propellants require special insulated containers and vents to allow gas from the evaporating liquids to escape. The liquid fuel and oxidizer are pumped from the storage tanks to an expansion chamber and injected into the combustion chamber where they are mixed and ignited by a flame or spark. The fuel expands as it burns and the hot exhaust gases are directed out of the nozzle to provide thrust.

A hypergolic propellant is composed of a fuel and oxidizer that ignite when they come into contact with each other. No spark is needed. Hypergolic propellants are typically corrosive so storage requires special containers and safety facilities.

Monopropellants combine the properties of fuel and oxidizer in one chemical. By their nature, monopropellants are unstable and dangerous. Monopropellants are typically used in adjusting or vernier rockets to provide thrust for making changes to orbits once the payload is in orbit.

Advantages of liquid propellant rockets include the highest energy per unit of fuel mass, variable thrust, and a restart capability. Raw materials, such as oxygen and hydrogen are in abundant supply and a relatively easy to manufacture. Disadvantages of liquid propellant rockets include requirements for complex storage containers, complex plumbing, precise fuel and oxidizer injection metering, high speed/high capacity pumps, and difficulty in storing fueled rockets.

The Rocket Pioneers :

Authors Jules Verne and H. G. Wells wrote about the use of rockets and space travel and serious scientists soon turned their attention to rocket theory.

It was, of course, the 20th century that witnessed an explosion in the field of rocketry. By the end of the 19th century, the three men considered to be the primary pioneers of modern rocketry had been born and begun their studies, Konstantin Tsiolkovsky (Russian), Robert Goddard (American) and Hermann Oberth (German).

In 1898, a Russian schoolteacher, Konstantin Tsiolkovsky (1857-1935), proposed the idea of space exploration by rocket. In a report he published in 1903, Tsiolkovsky suggested the use of liquid propellants for rockets in order to achieve greater range. Tsiolkovsky stated that the speed and range of a rocket were limited only by the exhaust velocity of escaping gases. For his ideas, careful research, and great vision, Tsiolkovsky has been called the father of modern astronautics.

Hermann Oberth, a German scientist, also contributed to the theory and design of rockets. In 1923 he published a work in which he proved flight beyond the atmosphere is possible. In a 1929 book called "The Road to Space Travel" Oberth proposed liquid-propelled rockets, multistage rockets, space navigation, and guided and re-entry systems. He also advanced the idea of a transatlantic postal rocket for quick mail delivery. It was taken seriously at the time but never attempted.

From 1939 to 1945 he worked on German war rocket programs with such notables as Wernher von Braun. After the war he came to the United States where he again worked with von Braun. During the war one of the weapons the scientists were designing was reminiscent of Oberth's postal rocket. The German's wanted to build a rocket which would carry a bomb from Europe to strike New York City.

Most historians call Oberth and Tsiolkovsky the fathers of modern rocket theory. If that is so, an American, Dr. Robert H. Goddard, can be called the father of the practical rocket. His designs and working models eventually led to the German big rockets such as the V-2 used against the Allies in World War II. All three men are enshrined in the International Space Hall of Fame in Alamogordo, N.M.

Although rockets were used during World War I, they were of limited value. As was the case during the U.S. Civil War, rockets were simply not as effective as artillery weapons of the day. Rockets sometimes were employed both on land and at sea to lay smoke screens. Allied forces also used rockets as a method of illuminating battlefields. Rockets were exploded in a brilliant flash that could illuminate a battlefield for several seconds. Some rockets carried a parachute with a flare attached. As the parachute and flare dropped toward the ground, a battlefield could be illuminated for about 30 seconds.

Robert Goddard:

Robert Hutchings Goddard was born on October 5, 1882 in Worcester, Massachusetts. Early in his life, Goddard was inspired by works of science fiction, primarily "War Of The Worlds" by H.G. Wells and "From The Earth To The Moon" by Jules Verne. Completely independent of Tsiolkovsky, Goddard realized that the reaction principle would provide a foundation for space travel. But rather than focus entirely on theory, Goddard set out at an early age to become equipped to build and test the hardware he believed was necessary to best demonstrate the reaction principle. Again independent of Tsiolkovsky, he too theorized that a combination of liquid hydrogen and liquid oxygen would make an ideal propellant.

Considered a staunch patriot until his death, Goddard went to work for the Army in 1917 with the goal of designing rockets that would aid in the war effort. The work was conducted in California, and yielded the development of a small, hand-held rocket launcher similar to what was later called the bazooka. In 1919, Goddard published a work entitled "A Method Of Reaching Extreme Altitudes", which contained a detailed compilation of much of the research he had completed to date. It also included speculation on the possibilities of spaceflight. Goddard concluded that a combination of liquid oxygen and gasoline were the only practical fuels that could be used in his continuing research in the development of liquid-fueled rocket motors.

By 1924, Goddard had developed and tested a liquid oxygen pump and engine that functioned. The unit, however, was too small to actually be employed on a working rocket. But, with a working design, he began to plan more elaborate research. Goddard successfully test fired a pressure-fed liquid oxygen engine inside the Clark University physics laboratory on December 6, 1925. The engine was attached to a small test rocket housed inside a fixed stand. The engine was fired for about 24 seconds and lifted the rocket for about 12 seconds within its stand. On March 16, 1926 Goddard launched a 10-foot long rocket from a 7-foot long frame. The rocket reached a maximum altitude of 41 feet at an average velocity of 60 m.p.h. The rocket remained in the air for 2.5 seconds and flew a distance of 184 feet. While this flight did not even come close to matching the performance of gunpowder propelled rockets of years past, it remains one of the most significant events in the history of rocketry. Powered by a combination of liquid oxygen and gasoline, the rocket launched by Goddard on March 16, 1926 was the first to ever be launched using liquid fuel.

Following this flight, Goddard realized that his rocket was too small to be refined. He decided to develop larger rockets for further tests. Work was also begun on the development of a more elaborate launch tower. The new rockets incorporated innovative technology like flow regulators, multiple liquid injection, measurement of pressure and lifting force and an electrically fired igniter to replace a gunpowder fired igniter used previously. A turntable was also designed to produce spin stabilization.

The fourth launch of a liquid-fueled rocket occurred on July 17, 1929. Considered much more elaborate than the first three, Goddard equipped the rocket with a barometer, thermometer and a camera to record their readings during flight. The rocket achieved a maximum altitude of 90 feet in an 18.5-second flight covering a distance of 171 feet. The scientific payload was recovered safely via parachute. However, the launch was so noisy and bright that it captured much public attention. Many eyewitnesses believed an aircraft had crashed in the area. Local fire officials quickly forced Goddard to discontinue his launch operations at the Auburn site.

Goddard then made a large move after deciding to embark on his first full-time effort at constructing and testing rockets. He set up shop at the Mescalero Ranch near Roswell, New Mexico in July, 1930. The relocation was initially financed through the Guggenheim grant. The first Roswell launch occurred on December 30, 1930 using a rocket 11 feet long by 12 inches wide and weighing 33.5 pounds empty. The test was impressive as the rocket reached a maximum altitude of 2,000 feet and maximum speed of 500 m.p.h. The rocket employed a new gas pressure tank to force the liquid oxygen and gasoline into the combustion chamber.

In the years approaching World War II, Goddard had agreed to allow military officials to review his research. On May 28, 1940 Goddard and Harry F. Guggenheim had met with a joint committee of Army and Navy officials in Washington, D.C. A complete report was given to these officials by Goddard which outlined his advances in both solid-fueled and liquid-fueled rockets. The Army rejected the prospect of long-range rockets altogether. The Navy expressed a minor interest in liquid-fueled rockets. Goddard later characterized these responses as negative. Neither branch of service was interested in an innovative rocket aircraft that had been patented by Goddard on June 9, 1931. The lack of military interest in rocketry had confounded Goddard for years, since he understood that only the government had adequate resources to fund proper research.

 

[BigRay]

A-10" redirects here. A-10 and A10 also have other uses.

The Fairchild-Republic A-10 Thunderbolt II is a single-seat, twin-engine jet aircraft designed to provide close air support (CAS) of ground forces by attacking tanks, armored vehicles, and other ground targets. As a secondary mission, it provides airborne forward air control, guiding other attack aircraft against ground targets. It is the first US Air Force aircraft designed exclusively for close air support (CAS) of ground forces. The official nickname comes from the P-47 Thunderbolt of World War II, a plane that was particularly effective at the CAS mission. However, it is more commonly known as Warthog or simply Hog. In the USAF inventory, the same airframe is also designated OA-10 when used primarily in a forward air control role.
Contents
[hide]

* 1 Origins
* 2 Features
* 3 Weapons Systems
* 4 Criticisms
* 5 Operational service
* 6 Nicknames
o 6.1 Friendly Forces
o 6.2 Enemy Forces
* 7 Trivia
* 8 Variants
* 9 Operators
* 10 Specifications (A-10 Thunderbolt II)
* 11 Flight Simulations
* 12 References
* 13 External links
* 14 Related content


USAF A-10A Thunderbolt II
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USAF A-10A Thunderbolt II
[edit]

Origins

The A-10 was developed in response to the increasing vulnerability of ground attack-planes to ground air defenses, as evidenced by the large number that were shot down by small arms fire, surface-to-air missiles, and low level anti-aircraft gunfire during the Vietnam War. This indicated the need for a specialized, heavily armored aircraft with long loiter time and large ordnance load, much like the Ilyushin Il-2 or A-1 Skyraider.

On 6 March 1967 the US Air Force released a request for information to 21 companies. Their objective was to create a design study for a low cost attack aircraft designated A-X, or "Attack Experimental". In May 1970, the USAF issued a modified, and much more detailed request for proposals (RFP). Six companies submitted contestants to the USAF, with Northrop and Fairchild Republic selected to build prototypes: the YA-9A and YA-10A, respectively.

The YA-10A first flew in May 1972. After trials and a flyoff against the YA-9A, the Air Force selected Fairchild-Republic's YA-10A on 10 January 1973 for production. The first production A-10 flew in October 1975, and deliveries to the Air Force commenced in March 1976. The first squadron to use the A-10 went operational in October 1977. In total, 715 aircraft were produced, the last in 1984.
USAF A-10 Thunderbolt from 1975
Enlarge
USAF A-10 Thunderbolt from 1975

One experimental two-seat version was built. The Night Adverse Weather aircraft was developed by Fairchild from an A-10 prototype for consideration by the USAF. It included a second seat for a weapons officer responsible for ECM, navigation, and target acquisition. The variant was cancelled and the only two-seat A-10 built now sits at Edwards AFB awaiting a spot in the Flight Test Historical Foundation museum.
Four A-10 Thunderbolt IIs fly in formation during a refueling mission.
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Four A-10 Thunderbolt IIs fly in formation during a refueling mission.
[edit]

Features

The A-10 has superior maneuverability at low speeds and altitude, thanks to straight, wide wings. These also allow short takeoffs and landings, permitting operations from rugged, forward airfields near front lines. The plane can loiter for extended periods of time and operate under 1,000 feet (300 m) ceilings with 1.5-mile (2.4 km) visibility. It typically flies at a relatively slow speed of 180 knots (200 mph or 320 km/h), which makes it much better candidate for the ground-attack role than fast fighter-bombers, which often have difficulty targeting small and slow-moving targets.

The 'Warthog' is exceptionally hardy, with a strong airframe that can survive direct hits from armor-piercing and high-explosive projectiles up to 23 mm. The aircraft has triple redundancy in its flight systems, with mechanical systems to back up double-redundant hydraulic systems. This permits pilots to fly and land when hydraulic power or part of a wing is lost. The aircraft is designed to fly with one engine and half a wing torn off. Self-sealing fuel tanks are protected by fire-retardant foam. Additionally, the main landing gear is designed so that the wheels semi-protrude from their nacelles when the gear is retracted so as to make gear-up landings (belly landing) easier to control and less damaging to the aircraft's underside.

The cockpit and parts of the flight-control system are protected by 900 pounds (400 kg) of titanium armor, referred to as a "titanium bathtub." The tub has been tested to withstand multiple strikes from 20 mm cannon fire. The thickness of the titanium varies from ½ an inch to 1½ inches determined by study on likely trajectories and deflection angles. This protection comes at a cost, though; the armour plating itself weighs almost 6% of the entire aircraft’s empty weight. To protect the pilot from the fragmentation likely to be created from impact of a shell any interior surface of the bath that is directly exposed to the pilot is covered by a multi-layer nylon spall shield. The protection for the pilot from above obviously comes second to the necessity for the pilot to have good all-round vision. The canopy cannot protect the pilot as well as the titanium, but the bullet-proof diffusion-bonded stretched-acrylic canopy can withstand small arms fire and is spall-resistant, although the canopy needs to be penetrable by the ejection seat.

Recent proof of the durability of the A-10 was shown when USAF Captain Kim Campbell, flying a ground support mission over Baghdad during the 2003 invasion of Iraq suffered extensive flak damage to her A-10. The hit damaged one of the A-10's two engines and destroyed its hydraulic system, disabling the plane's stabilizer and flight controls. Despite this, the pilot managed to fly it for an hour and landed it safely at the air base in manual reversion mode ("Killer Chick" tells her story).
This A-10 Thunderbolt II suffered extensive damage over Baghdad but still made it back to base
Enlarge
This A-10 Thunderbolt II suffered extensive damage over Baghdad but still made it back to base

Engine exhaust passes over the aircraft's horizontal stabilizer and between the twin tails, decreasing the A-10's infrared signature and lowering the likelihood that the aircraft can be targeted by heatseeking missiles. The placement of the engines partially shields them from anti-aircraft fire behind the wings and tail. The A-10 can fly even after the loss of one side of the tail, ⅔ of a single wing, and one engine.

The A-10 has integrally machined skin panels. Because the stringers are integral with the skin there are no join or seal problems. These panels built using computer controlled machining reduce the man-hours and hence the cost of manufacture. The tests of war have shown that this type of panel is more battle-hardy.

Most thin flat areas of the airframe are honeycomb panels. This is because thin honeycomb sandwich panels are less likely to deform in any direction than sheet metal panels even if part of the panel has been blown off or structurally compromised. Such honeycomb panels on this aircraft include the flap shrouds, the elevators, the rudders and other sections of the fins. The leading edge of the mainplane is honeycomb to provide strength with minimal weight compromise.

The ailerons are at the far ends of the wings to gain greater rolling moment as with most aircraft but there are two distinguishing features. First the ailerons are larger than is typical, almost 50% of the chord, providing improved control even at slow speeds. The aileron is also split, allowing the halves to separate and function as airbrakes.

The Thunderbolt II can be serviced and operated from bases with limited facilities near battle areas. An unusual feature is that many of the aircraft's parts are interchangeable between the left and right sides, including the engines, main landing gear, and vertical stabilizers. The sturdy landing gear, low-pressure tires and large, straight wings allow operation from short rough strips even with a heavy ordnance load, allowing the aircraft to operate from damaged airbases. The aircraft is designed to be re-fueled, re-armed, and serviced with minimal equipment. Operating from a forward area is both useful for close air support and necessary due to the A-10's relatively low cruise and top speeds.

One of the characteristic features of this aircraft is the placement of the General Electric TF34-GE-100 turbofan engines. There are many reasons for the location of the engines on the Warthog. First, as this aircraft was expected to be operated from forward air bases, often with semi-prepared substandard runways, there would be a high risk of FOD (Foreign Object Damage). The height of the engines significantly lowers the chance of sand or stones damaging the complex parts of the jet engines. This also allows the engines to remain running allows for quickier servicing and rearming turn-around times by ground crew. Servicing and rearming are further helped by the wings having a reduced height above ground than if the engines were under-slung or integral to the wing. As mentioned above the position also reduces the IR signature which starts low anyway due to the high bypass ratio of the engines. The bypass ratio is 6:1 and so the engines are very quiet which aids against detection. Because of their high position, the engines are angled upward nine degrees to bring the combined thrust line closer to the aerodynamic center of the aircraft. This avoids nuisance trimming measures to counteract a nose down pitching moment if the engines were parallel to the fuselage.

The engines, being particularly heavy components, require a high degree of strength in their support. Therefore forged engine-mounting nacelle frames are pin jointed to machined support beams.

All four fuel tanks are near the center of the aircraft thus decreasing the likelihood of them being hit or being separated from the engines. There are several methods employed to protect the tanks themselves. The tanks are separate from the fuselage and so projectiles would need to penetrate the skin before reaching the tank. The refueling system is purged after use so that there is no fuel unprotected anywhere in the aircraft. All pipes self-seal if they are compromised. Most of the fuel system components are situated inside the tanks so that if a leak were to occur from the component the fuel would not be lost. If a tank does get damaged there are check valves that can ensure that fuel does not flow into the compromised tank. The most important fuel system protection aid is the reticulated polyurethane foam that is sprayed into the empty space in a tank holding debris and restricting fuel spillage in the event of damage. The other source of possible combustion, the engines, are shielded from the fuel system and the rest of the airframe by firewalls and fire extinguishing equipment.
[edit]

Weapons Systems
The A-10's GAU-8 Avenger gun
Enlarge
The A-10's GAU-8 Avenger gun

Although the A-10 can carry a considerable weight of disposable stores, its primary built-in weapon is the 30 mm GAU-8/A Avenger Gatling gun. One of the most powerful aircraft cannon ever flown, it fires large, depleted uranium armor-piercing shells at a rate of about 3,900 rounds per minute (50 rounds per second during the first second followed by 70 rounds per second). The massive shells and high muzzle velocity allow the Avenger to destroy heavily armored main battle tanks in as little as 6 direct hits. The gun is accurate as well, capable of placing 80% of its shots within a 30-foot wide circle from a distance of 1 mile while the aircraft is in flight. The chassis of the plane is actually built around the gun (for instance, the nosewheel is offset to starboard so that each barrel of the gun can be aligned on the centreline when it fires.) The A-10 carries 1,350 rounds of 30 mm ammunition and the damage caused by a proportion of those rounds prematurely firing from impact of an explosive shell would be catastrophic. It is for this reason that a great deal of effort has been taken to protect the 5 ft (1.52m) wide, 9 ft (2.74m) long drum. There are many plates of varying thicknesses between the skin and the drum, these plates are called trigger plates because when an explosive shell hits a target it first penetrates its armour then detonates, as the drum has many layers of thin armour the shells detonation is triggered before reaching the drum. Then a final layer of armour around the drum itself protects it from fragmentation damage.
A-10 Thunderbolt II fully loaded with armaments in flight
Enlarge
A-10 Thunderbolt II fully loaded with armaments in flight

Despite the power of the GAU-8, the principal weapon of the A-10 is the AGM-65 Maverick air-to-surface missile, with electro-optical targeting. The Maverick allows targets to be engaged at much greater ranges than the cannon, a safer proposition in the face of modern anti-aircraft systems. During Desert Storm, in the absence of NVG, the Maverick's camera was used for night missions. Other weapons include cluster bombs and rocket pods. Although the A-10 is equipped to deliver conventional and laser-guided bombs, their use is relatively uncommon. A-10s usually fly with an ECM pod under one wing and two AIM-9 Sidewinder air-to-air missiles under the other for self-defense.
[edit]

Criticisms

The A-10 has been criticized for its minimal avionics fit. It was originally intended purely for close air support, for which it was felt that complex electronics would be unnecessary (and would have an undesirable effect on serviceability and cost). Initial fit provided basic communications, a radar-warning system, and TACAN navigation, early aircraft lacking even an autopilot. As USAF emphasis shifted towards the anti-armor role, presumably in a conflict with the Warsaw Pact forces in Western Europe, where weather is frequently poor, there was pressure for improved sensors and electronics. Fairchild-Republic offered a two-seat Night and Adverse Weather (NAW) variant beginning in 1977, but it was not adopted. Aircraft were eventually upgraded with inertial navigation and a Pave Penny laser sensor (marked target seeker) pod that allowed the pilot to detect laser energy for PID (Positive Identification) of an illuminated target. The Pave Penny is a passive seeker and cannot self-designate a target for a Laser Guided Bomb (LGB). However, the A-10 can drop LGBs with the help of another aircraft (Buddy-Lase) or, when equipped with a targeting pod (Self-Lase).

The A-10 also initially lacked systems to compute target range or impact points, greatly limiting its ability to deliver weapons other than cannon and rocket fire (in direct, visual-range attacks) or the self-guided AGM-65 Maverick missile, whose own sensors displayed imagery in the A-10's cockpit. Often times this small monitor would provide the only source of imagery for missions that took place in dark environments. Much later in the "Warthog's" career, the Low-Altitude Safety and Targeting Enhancement (LASTE) upgrade provided computerized weapon-aiming equipment, an autopilot, and ground-collision warning system. The A-10 is now compatible with night-vision goggles for low-light operation. In 1999, aircraft began to be given Global Positioning System navigation systems.

With the end of the Cold War and the decreasing likelihood of a conflict between the United States and a Soviet style army (in other words, a heavily mechanized force) the continued need for the tank-busting A-10 has been questioned. Several efforts to withdraw the A-10 Thunderbolt from active service have been made over the years. However in recent conflicts, such as the 2001 war in Afghanistan and the 2003 invasion of Iraq the A-10 proved useful as it can destroy any vehicle it can locate.
[edit]

Operational service
An A-10 Thunderbolt in flight
Enlarge
An A-10 Thunderbolt in flight

The first unit to receive the A-10 Thunderbolt II was the 355th Tactical Training Wing, based at Davis-Monthan Air Force Base, Arizona in March 1976.

A-10s were initially an unwelcome addition to the arsenal in the eyes of Air Force brass. The Air Force prized the high-flying, high-performance F-15 and F-16 jets, and were determined to leave the dirty work of close air support to Army helicopters.

The planes proved their mettle in the Persian Gulf War in 1991, destroying more than 1,000 tanks, 2,000 military vehicles and 1,200 artillery pieces. Five A-10s were shot down during the war (a number of those by ZSU-23-4 Shilka anti-aircraft systems), far fewer than military planners expected. A-10s had a mission capable rate of 95.7%, flew 8,100 sorties and launched 90% of the AGM-65 Maverick missiles.

In the 1990s many A-10s were shifted to the "forward air control (FAC)" role and redesignated OA-10. In the FAC role the 'Warthog' is typically equipped with up to six pods of 5 inch (127 mm) Zuni rockets, usually with smoke or white phosphorus warheads used for target marking. They remain fully combat capable despite the redesignation.

A-10s again saw service in the 1999 Kosovo War, in later stages of the 2001 invasion of Afghanistan from an air base at Bagram, including Operation Anaconda in March 2002, and in the 2003 Iraq war. Sixty A-10s were deployed in Iraq; one was shot down near Baghdad International Airport by Iraqi fire late in the campaign.
Two A-10 Thunderbolts in flight
Enlarge
Two A-10 Thunderbolts in flight

A-10 pilots have been involved in a number of notorious 'friendly fire' incidents. In the Gulf War of 1991 an A-10 attacked two British Army Warrior Infantry Fighting Vehicles (out of 37 parked up), killing nine soldiers. Two British Scimitar armored reconnaissance vehicles were attacked by an A-10 in the Iraq War of 2003. They were also involved in a friendly fire incident with a U.S. Marine Amphibious Assault Vehicle at the Battle of Nasiriyah during the opening stages of Operation Iraqi Freedom.

The A-10 is scheduled to stay in service with the USAF until 2028, when it may be replaced by the F-35 (Joint Strike Fighter). Beginning in 2005 the entire A-10 fleet is being upgraded to the "C" model that will include improved FCS (fire control system), ECM (electronic countermeasures), and the ability to carry smart bombs. However, the A-10 could stay in service indefinitely due to both its low cost and its unique capabilities which the F-35 simply cannot incorporate such as its cannon, ruggedness, and slow flying capabilities.
[edit]

Nicknames
[edit]

Friendly Forces

The A-10 Thunderbolt II received the nickname "Warthog" or "Hog" and dates back to Fairchild-Republic's initial deliveries. There are several rumors that the name was derived from the report of the main gun, which has a surprisingly low pitch and sounds much like the snorting or grunting of a hog. This coupled with the A-10's lack of aesthetics and "thick skin" earned it the nickname "Warthog".

The real reason was that for production economy, the fuselage used different types of rivets. Only those forward of the trailing edge of the wing are flush-head. Those aft of the wing are protruding-head, which makes the skin surface look and feel "bumpy." (This was done since the boundary layer separates at this point on the fuselage, and therefore the bumpiness does not affect the drag of the aircraft.) When the A-10 was first delivered to Davis-Monthan AFB, the crew chiefs thought the protruding head rivets looked like warts, and dubbed the A-10 "the Warthog."
[edit]

Enemy Forces
81st Fighter Squadron Thunderbolt
Enlarge
81st Fighter Squadron Thunderbolt

At the time of the Gulf War captured Iraqi tank crews referred to it as "whispering death" while Iraqi soldiers and Afghan Taliban have in recent times also referred to the A-10 as "the silent gun". In both cases this can be attributed to the quietness of the low and slow-moving A-10, and its ability to engage targets with supersonic ammunition from distances that preclude hearing the incoming rounds before they impact. In the 2003 invasion of Iraq, several captured Fedayeen militiamen referred to the A-10 as "the devil's cross" because of its cross-like appearance from below.

Stories of enemies using fearsome nicknames to describe their opponents weapons are sometimes propaganda. For instance, during World War 2, the Allies claimed that Axis soldiers described some of their planes as "whispering death" and "flying porcupine," when in fact it was an invention to obliquely suggest the fearsomeness of Allied weapons.[citation needed]
Thunderbolt closeup
Enlarge
Thunderbolt closeup
[edit]

Trivia

The GAU-8/A 30 mm Avenger cannon is said to produce almost the same amount of force as one of the A-10's engines, leading to a persistent military legend that if enough bullets could be carried and fired in a long burst, the plane would stop flying (or move backwards, in some versions of the legend). Using the specs from the GAU-8/A product homepage, the recoil force of the GAU-8/A is measured to an average of 10,000 lbf (45 kN). While the recoil force is considerable, the cannon is employed only in short bursts to protect the barrel cluster from overheating. Even if both engines were stopped and the jet was gliding unpowered, firing the cannon will not bring it to a stop in midair, only slow it down much in the same manner as if an airbrake was deployed.

Of further note on the cannon recoil force, the A-10's nosewheel gear assembly is situated in the less than optimal off-center-line position (immediately starboard of the gun). This design feature was necessary to accommodate the GAU-8 in the center-line position as an off-center placement would result in detrimental yaw loads when firing the cannon.
[edit]

Variants

* YA-10A : The first two prototypes.
* A-10A : Single-seat close air support, ground-attack version.
* OA-10A : Single-seat forward air control version.
* Night/Adverse Weather A-10 : Two-seat experimental prototype, for night and adverse weather work. Later redesignated YA-10B. One aircraft only.
* A-10C : Updated version of A-10 featuring a digital cockpit, and all-weather multi-mission precision weapons capability.

[edit]

Operators

* United States Air Force

[edit]

Specifications (A-10 Thunderbolt II)

Data from The Great Book of Modern Warplanes[1]
General characteristics

* Crew: 1
* Length: 53 ft 4 in (16.26 m)
* Wingspan: 57 ft 6 in (17.53 m)
* Height: 14 ft 8 in (4.47 m)
* Airfoil: NACA 6716 root, NACA 6713 tip
* Empty weight: 24,959 lb (11,321 kg)
* Loaded weight:
o Standard: 30,384 lb (13,782 kg)
o On CAS mission: 47,094 lb (21,361 kg)
o On anti-armor mission: 42,071 lb (19,083 kg))
* Max takeoff weight: 50,000 lb (23,000 kg)
* Powerplant: 2× General Electric TF34-GE-100A turbofans, 9,065 lbf (40.32 kN) each

Performance

* Never exceed speed: 450 knots (520 mph, 830 km/h)
* Maximum speed: 380 knots (438 mph, 704 km/h) at 5,000 ft (1,500 m) with 6 Mk 82 bombs
* Cruise speed: 300 knots (340 mph, 560 km/h)
* Combat radius:
o On CAS mission: 250 nm (290 mi, 460 km) at 1.88 hour single-engine loiter at 5,000 ft (1,500 m), 10 min combat
o On anti-armor mission: 252 nm (166 mi, 267 km), 40 nm (45 mi, 75 km) sea-level penetration and exit, 30 min combat
* Ferry range: 2,240 nm (2,580 mi, 4,150 km) with 50 knot (55 mph, 90 km/h) headwinds, 20 minutes reserve
* Service ceiling: 45,000 ft (13,700 m)
* Rate of climb: 6,000 ft/min (30 m/s)
* Wing loading: 99 lb/ft² (482 kg/m²)
* Thrust/weight: 0.36

Armament

* Guns: 1× 30 mm (1.18 in) GAU-8/A Avenger gatling gun with 1,350 rounds
* Hardpoints: 8× underwing and 3× under-fuselage pylon stations holding up to 16,000 lb (7,200 kg) and accommodating:
o Mark 82, Mark 83, and Mark 84 general-purpose bombs or
o Mk 77 incendiary bombs or
o BLU-1, BLU-27/B Rockeye II, BL755 and CBU-52/58/71/87/89/97 cluster bombs or
o GBU-10 Paveway II, GBU-12 Paveway II, GBU-16 Paveway II and GBU-24 Paveway III laser-guided bombs or
o AGM-65 Maverick and AIM-9 Sidewinder air-to-air missiles or
o LAU-68 Hydra 70 mm (2.76 in) and 127 mm (5.0 in) rocket pods or
o Illumination flares, ECM and chaff pods or
o ALQ-131 ECM pod

 

[BigRay]

Mustard
Brassica alba, B. juncea, B. nigra
syn: Sinapsis alba
Fam: Cruciferae




It was the condiment, not the plant, that was originally called mustard. The condiment got its name because it was made by grinding the seeds of what was once called the senvy plant into a paste and mixing it with must (an unfermented wine). Mustard is one of the oldest spices and one of the most widely used. The Chinese were using mustard thousands of years ago and the ancient Greeks considered it an everyday spice. The first medical mention of it is in the Hippocratic writings, where it was used for general muscular relief. The Romans used it as a condiment and pickling spice. King Louis XI would travel with his own royal mustard pot, in case his hosts didn’t serve it. Today, world consumption of mustard tops 400 million pounds.

Spice Description
The Brassica genus includes broccoli, cabbage, cauliflower, turnips and radishes. The mustard family also includes plants grown for their leaves, like arugula, a number of Oriental greens, as well as mustard greens. Three related species of mustard are grown for their seeds:
White Mustard (Brassica alba or Brassica hirta) is a round hard seed, beige or straw coloured. Its light outer skin is removed before sale. With its milder flavour and good preservative qualities, this is the one that is most commonly used in ballpark mustard and in pickling.
Black Mustard (Brassica nigra) is a round hard seed, varying in colour from dark brown to black, smaller and much more pungent than the white.
Brown Mustard (Brassica juncea) is similar in size to the black variety and vary in colour from light to dark brown. It is more pungent than the white, less than the black.
Bouquet: The seed itself has no aroma.
Flavour: Sharp and fiery.
Hotness Scale: 3-8

Preparation and Storage
Whole seeds are included in most pickling spices. Seeds can also be toasted whole and used in some dishes. Powdered mustard is usually made from white mustard seed and is often called mustard flour. When dry, it is as bland as cornstarch — mixed with cool water its pungency emerges after a glucoside and an enzyme have a chance to combine in a chemical reaction (about ten minutes). Don’t use hot water as it will kill the enzyme and using vinegar will stop the reaction so that its full flavour will not develop. Once the essential oils have formed, then other ingredients can be added to enhance the taste: grape juice, lemon or lime juice, vinegar, beer, cider or wine, salt, herbs, etc.

Culinary Uses
Whole white mustard seed is used in pickling spice and in spice mixtures for cooking meats and seafood. It adds piquancy to Sauerkraut and is sometimes used in marinades. In India, whole seeds are fried in ghee until the seed pops, producing a milder nutty flavour that is useful as a garnish or seasoning for other Indian dishes. The brown seed is also pounded with other spices in the preparation of curry powders and pastes. Mustard oil is made from B. juncea, providing a piquant oil widely used in India in the same way as ghee. Powdered mustard acts as an emulsifier in the preparation of mayonnaise and salad dressings. Powdered mustard is also useful for flavouring barbecue sauces, baked beans, many meat dishes, deviled eggs, beets and succotash. There are many ready-made mustards from mild and sweet to sharp and strong. They can be smooth or coarse and flavoured with a wide variety of herbs, spices and liquids.

American ballpark-style mustard is made from the white seeds and blended with sugar and vinegar and coloured with turmeric.

Bordeaux mustard is made from black seeds blended with unfermented wine. The seeds are not husked, producing a strong, aromatic, dark brown mustard often flavoured with tarragon.

Dijon mustard is made from the husked black seeds blended with wine, salt and spices. It is pale yellow and varies from mild to very hot. This is the mustard generally used in classic French mustard sauces, salad dressings and mayonnaise.

English mustard is hot, made from white seeds and is sometimes mixed with wheat flour for bulk and turmeric for colour.

German mustard is usually a smooth blend of vinegar and black mustard, varying in strength. Weisswurstsenf is a course grained, pale, mild mustard made to accompany veal sausages like Bratwurst.

Meaux mustard is the partly crushed, partly ground black seed mixed with vinegar, producing a crunchy, hot mustard that perks up bland foods.

Attributed Medicinal Properties
Historically, mustard has always held an important place in medicine. The ancient Greeks believed it had been created by Asclepious, the god of healing, as a gift to mankind. Although the volatile oil of mustard is a powerful irritant capable of blistering skin, in dilution as a liniment or poultice it soothes, creating a warm sensation. Mustard plasters are still used today as counter-irritants. Over the years mustard has been prescribed for scorpion stings and snake bites, epilepsy, toothache, bruises, stiff neck, rheumatism, colic and respiratory troubles. It is a strong emetic (used to induce vomiting) and rubefacient (an irritant) that draws the blood to the surface of the skin to warm and comfort stiff muscles. It is useful in bath water or as a foot bath, as “It helpeth the Sciatica, or ache in the hip or huckle bone” .(Gerard, 1579).

Colman's Mustard
Colman's Mustard
Buy this Giclee Print
at AllPosters.com



Plant Description and Cultivation
An erect herbaceous annual. The white variety (B. alba) is hardy, growing to 80 cm (30 in), with hairy stems and lobed leaves. The bright yellow flowers yield hairy fruit pods, 2.5 - 5 cm (1-2 in) long, each containing about six seeds.
Black mustard (B. nigra) is a larger plant than the white, reaching to 1 m (39 in). Some varieties reach double this height. The flowers are smaller, as are the fruit pods at 2 cm (3/4 in) long. The pods are smooth and bulging, containing about a dozen seeds. Because of its height black mustard does not lend itself well to mechanical harvesting and since the seed is readily shed when ripe, there is too much waste for most commercial growers. As a result it has almost completely been replaced by the brown variety.
Brown mustard (B. juncea) is similar to black mustard in size. It is the rai of India. The leaves are ovate and the pods are 3 -5 cm (1-1/4 to 2 in) long.
Mustard pods must be harvested before they burst, that is when they are nearly fully developed but not ripe.





Other Names
White
Yellow Mustard (US)
French: moutarde blanche
German: Senf, Weisser Senf
Italian: senape biancha
Spanish: mostaza silvestre

Black
Brown mustard (UK), Grocer’s mustard
French: moutarde noire
German: Schwarzer Senf
Italian: senape nera
Spanish: mostaza negra
Chinese: Banarsi rai, rai, kurva teil (oil)
Indian: Banarsi rai, rai, kurva teil (oil)
Japanese: karashi
Malay: diji savi
Singhalese: abba

Brown
Indian Mustard
French: moutarde de Chine
German: Indischer Senf
Italian: senape Indiana
Spanish: mostaza India
Indian: kimcea, Phari rai, rai

 

[BigRay]

New Study Finds Potential Ovarian Cancer Stem Cells

Adapted from the following source: Massachusetts General Hospital

Massachusetts General Hospital (MGH) researchers have identified potential ovarian cancer stem cells. These cells may be behind the difficulty of treating ovarian tumors with standard chemotherapy.

Understanding more about the stem-like characteristics of these cells could lead to new approaches to treating ovarian cancer. Ovarian cancer kills more than 16,000 U.S. women annually and is the fifth most common cause of cancer death. The report appears in the July 25, 2006 issue of the Proceeding of the National Academy of Sciences (PNAS).

"We feel these stem-like cancer cells may be resistant to traditional chemotherapy and could be responsible for the ultimately fatal drug-resistant recurrence that is characteristic of ovarian cancer," says Paul Szotek, MD, of the MGH Pediatric Surgical Research Laboratories, first author of the PNAS report. "We believe this likely is the first time stem-like cells have been found in models of ovarian cancer and in cells associated with human ovarian cancer."

Several recent studies have identified tiny populations of tumor cells that appear to act like stem cells. This drives the tumor's ability to grow and spread.

If some of these specialized cells escaped destruction by chemotherapy or radiation, the tumor would be able to recur quickly, often in a form resistant to chemotherapy. Similar cancer stem cells have been previously identified in leukemia and breast cancer and in cell lines of central nervous system and gastrointestinal tumors.

Standard treatment for ovarian cancer involves surgical removal of all involved tissues followed by chemotherapy. It usually appears successful, but treatment-resistant tumors recur in the vast majority of patients. As a result, the five-year survival rate following this treatment protocol is less than 30 percent.

Those factors and other observations suggested that cancer stem cells may also be found with ovarian tumors, leading to the current study.

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Researchers Transform Stem Cells Found In Human Fat Into Smooth Muscle Cells

Adapted from the following source: University of California, Los Angeles

Researchers have announced they have transformed adult stem cells taken from human fat tissue into smooth muscle cells, which help the normal function of a multitude of organs, including the intestine, bladder and arteries. The study may help lead to the use of fat stem cells for smooth muscle tissue engineering and repair.

Smooth muscle cells are found within the human body in the walls of hollow organs like blood vessels, the bladder and the intestines; they contract and expand to help transport blood, urine and waste through the body's systems.

"Fat tissue may prove a reliable source of smooth muscle cells that we can use to regenerate and repair damaged organs," said Dr. Larissa V. Rodriguez, principal investigator and assistant professor in the department of urology at the David Geffen School of Medicine at UCLA.

Rodriguez noted the many advantages of using a patient's own fat stem cells for organ re-growth and tissue regeneration, including the lack of need for anti-rejection medications. For patients with a diseased or absent organ, who cannot use their own organ tissue for regeneration, adipose stem cells offer an alternative.

Smooth muscle cells have also been produced from stem cells found in the brain and bone marrow, but acquiring stem cells from fat tissue is much easier, and most patients have fat tissue readily available, according to Rodriguez.

The next step, Rodriguez said, involves identifying and developing the growth factors that will induce transformation of cells more quickly.

The research was performed at the David Geffen School of Medicine at the University of California, Los Angeles (UCLA) and the UCLA Henry Samueli School of Engineering and Applied Science. The findings were reported in the July 24 online edition of the Proceedings of the National Academy of Sciences.

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President Bush’s Veto Of Stem Cell Bill Dashes Hope For 100 Million Americans

Adapted from the following source: Sean Tipton, President of the Coalition for the Advancement of Medical Research (CAMR)

“President Bush single-handedly dashed the hopes and prayers of the American people today while severely compromising America’s leadership position in the fields of science and medicine. By issuing the first veto ever during his Presidency to shoot down the Stem Cell Research Enhancement Act, President Bush once again ignored the will of the people and the best scientific expertise and advice in favor of the wishful thinking of his political advisors.

“Nearly three-quarters of Americans and the majority of both the Republican-led House and Senate support federal funding for embryonic stem cell research. For the President to give in to an extremist, single-issue minority on this issue is a travesty.

“More than 100 million Americans suffer from cancer, Parkinson’s, Alzheimer’s, diabetes, spinal cord injuries and other debilitating diseases and disorders for which embryonic stem cell research holds great promise in finding new and better treatments and cures. Those individuals, along with their families, friends, and caregivers, will remember this day as the day their President signed away their right to life, liberty and the pursuit of happiness.

“It’s a sad day in America when a President thinks it is okay to say:

* To the toddler with diabetes, we’re sorry that you’ll have to endure 3,000 finger sticks and 1,000 insulin shots every year for the rest of your life.
* To the father suffering from Parkinson’s, we’re sorry that you may not get to see your daughter walk down the aisle at her wedding.
* To the college student with a spinal cord injury, we’re sorry that you may never have the chance to leave your wheelchair behind and walk again.

“Despite our outrage and anger at this veto, we will continue to do whatever we can to advance embryonic stem cell research in America. We will always be grateful for the strong, bipartisan support on this issue in both the U.S. Senate and House of Representatives, and among the American people.”

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Stem Cell Research Foundation Applauds Passage of Stem Cell Research Enhancement Act

(Clarksburg, MD): "We applaud the U.S. Senate for passing the Stem Cell Research Enhancement Act today,” said Stem Cell Research Foundation President Brian K. Regan, Ph.D. “This bill helps make sure stem cell research can fulfill its full potential for improving the lives of millions of Americans afflicted by debilitating diseases and conditions.”

The bill expands the number of stem cell lines that are eligible for federally funded research. Currently, federal policy on human embryonic stem cell research permits only the use of stem cell lines derived before August 9, 2001 for federally funded research.

The Stem Cell Research Enhancement Act lifts that restriction. Stem cell lines shall be eligible for federally funded research regardless of the date on which they were derived.

The bill also institutes stronger ethical requirements on stem cell lines that are eligible for federally funded research.

Established in 2000, Stem Cell Research Foundation is a not-for-profit organization designated under Section 501©(3) of the Internal Revenue Code.

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New Findings May One Day Help Scientists Grow Specialized Cells For Treating Neurological Disorders

Adapted from the following source: University of Florida

Embryonic stem cells, prized for their astonishing ability to apparently transform into any kind of cell in the body, acquire their identities in part by interacting with their surroundings—even when they are outside of the body in a laboratory dish, University of Florida (UF) scientists report.

Using an animal model of embryonic stem cell development, researchers with UF's McKnight Brain Institute have begun to answer one of the most fundamental questions in science—how does a batch of immature cells give rise to an organ as extraordinarily complex as the human brain?

The findings, to be published in the June 2006 issue of the Proceedings of the National Academy of Sciences, may one day help scientists create laboratory environments to grow specialized cells that can be transplanted into patients to treat epilepsy, Parkinson's, Huntington's and Alzheimer's diseases or other brain disorders.

Scientists observed that when embryonic stem cells from mice were plated on four different surfaces in cell culture dishes, specific types of cells would arise.

"The medium and the molecular environment influence the fate of the cell," said Dennis Steindler, Ph.D., executive director of the McKnight Brain Institute. "We simulated some events that occur while the brain is developing and challenged them with different environments, and the effects are profound. Ultimately both nature and nurture influence the final identity of a stem cell, but in early stages it seems nurture is very important."

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Stem Cell Research Raises Hopes For A Gene Therapy To Combat AIDS

Adapted from the following source: University of California, Los Angeles

Researchers from the University of California, Los Angeles (UCLA) AIDS Institute and the Institute for Stem Cell Biology and Medicine have demonstrated for the first time that human embryonic stem cells can be genetically manipulated and coaxed to develop into mature T-cells, raising hopes for a gene therapy to combat AIDS.

The study, to be published the week of July 3 in the online edition of the Proceedings of the National Academy of Sciences, found that it is possible to convert human embryonic stem cells into blood-forming stem cells that in turn can differentiate into the helper T-cells that HIV specifically targets. T-cells are one of the body's main defenses against disease.

The results mark the first time that scientists have been able to derive T-cells out of human embryonic stem cells, said Zoran Galic, assistant research biologist, and lead researcher on the study.

"This tells you that you may be able to use human embryonic stem cells to treat T‑cell and other blood diseases. This could be a very important weapon in the fight against AIDS," Galic said.

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[walters]

your pretty childish Bigray please don't trash up my thread because your a failed musician that never made it and is mad u trashed your own life don't trash up mine and my thread bigray

 

[BigRay]

your pretty childish Bigray please don't trash up my thread because your a failed musician that never made it and is mad u trashed your own life don't trash up mine and my thread bigray

Prominences are a major unsolved puzzle in solar physics. How can cool, dense material form and remain suspended in the hot tenuous corona? Our explanations for both the formation and the support are based on two key observed or inferred properties of the solar atmosphere: a highly sheared filament-channel magnetic field located around a polarity inversion line (PIL), and heating concentrated near the base of the corona. The research described here and under Solar Eruptions represents substantial progress toward a complete, self-consistent model for the entire prominence lifecycle.

[T shallow-dip symmetric case] [emissivity in 3 lines, low arch case] [T deep dip case]
Fig. 1 Fig. 2 Fig. 3

Our model for the formation of prominence condensations relies on the thermal nonequilibrium inherent in the radiative characteristics of the solar corona. Through 1D modeling we have shown that if the heating into a coronal fluxtube (or loop), which is dipped near its midpoint (see below), has a strong spatial variation so that this heating is concentrated near both chromospheric footpoints, then sufficient material can evaporate into the dipped portion to instigate a catastrophic thermal collapse there. Figure 1 shows the time evolution of the temperature vs. distance along the loop, culminating in the creation of a stable condensation at the top. The distance from loop base to top (left to right on the horizontal axis) is 110 Mm, including a 60 Mm thick chromospheric region; the maximum temperature (vertical axis) is 1.75 MK; and the real-time duration of the movie is 90,000 s, with the localized heating turned on and maintained for the latter 2/3 of this interval. See Dahlburg, Antiochos, & Klimchuk (1998), and Antiochos, MacNeice, Spicer, & Klimchuk (1999) in Bibliography for details.

The extension of these calculations to asymmetrically heated dipped and arched loops has demonstrated the broad applicability of our mechanism for prominence formation. We have discovered that, when heating asymmetries are considered, the condensation process is inherently dynamic and does not yield static structures. Rather, a cycle of condensation formation, oscillation, and destruction (through gravitational freefall onto the nearest chromospheric footpoint) is maintained as long as the footpoints are heated unequally. Our model, then, can explain high-cadence/high-resolution observations of counterstreaming flows of cool, dense knots along prominence spines (e.g., Zirker, Engvold, & Martin 1998; Lin et al. 2003). Although this was first demonstrated for dipped configurations, our subsequent 1D calculations have revealed that condensations can form in a wide range of loops without upward concavities, thus greatly expanding the set of field lines capable of constituting a prominence. Figure 2 shows the time evolution of the predicted emissivity in three commonly observed spectral lines --- Mg X, O V, and H-α --- for a long, arched loop with a peak height of 5 Mm, heated steadily but unequally at its footpoints. The key requirements for this process to occur are (1) localized heating in the lower atmosphere with a damping length much less than the loop length, as is consistent with most TRACE loops (e.g., Aschwanden, Schrijver, & Alexander 2001); and (2) loop apex heights below the gravitational scale height (higher loops form condensations that are small and short-lived, and hence unlikely to contribute significantly to the prominence mass). By investigating thermal nonequilibrium on a series of long field lines with progressively deeper dips, we also found that dynamic condensations only occur on field lines where the slope within the dip is less than a critical value . As shown in Figure 3, field lines with dips that exceed this critical slope support single condensations that rapidly fall to the bottom of the dip and remain there, growing steadily as long as the localized heating continues. Therefore, the filament channel structure is a key determinant of whether and where static or dynamic condensations can be formed therein. For more information on these studies see Antiochos, MacNeice, & Spicer (2000) and Karpen et al. (2001,2003) in Bibliography.

[area and height along flux tube] [condensation locations] [T movie, NRK case]
Fig. 4 Fig. 5 Fig. 6

To test this condensation process under more realistic conditions, we used our sheared 3D arcade model of the prominence magnetic field (see below) to define the geometry of the model flux tube in our most recent 1D simulations. We selected a representative field line capable of supporting condensations from the DeVore & Antiochos (2000) 3D MHD simulation, measured the flux tube cross-sectional area at intervals along these lines, and derived high-order polynomial fits to the height and area that were easily recomputed upon regridding (see Figure 4). For comparison, a constant cross-section ``control" loop also was set up with the same height variations. These field lines were subjected to localized heating near the footpoints, as before, and subsequent developments were monitored. We have explored the effects of uniform vs. nonuniform area (U vs N), changing the location of stronger localized heating (L vs R), and updating the radiative loss function (Original vs Klimchuk-Raymond). We have demonstrated the robustness of our combined model for prominence plasma and magnetic structure by verifying that steady localized heating yields prominence condensations on a typical field line from our sheared 3D arcade model. Furthermore, we find that the heating asymmetry, height variation, and area variation all dictate whether condensations become dynamic or static (see Figure 5; 3 letter designation refers to N or U area, L or R stronger heating, and O or K radiative loss function), and that the updated radiative loss function yields closer agreement with observations, e.g., more rapid formation, shorter interval between condensations, and higher downflow speeds (compare Fig. 6 and Fig. 3 animations, for example).

[sheared arcade simulation] [initial B field] [final B field]
Fig. 7 Fig. 8 Fig. 9

Because the gravitational scale height of the cool prominence material is much smaller than the observed height of these structures, some form of magnetic concavity has always been assumed necessary to support prominences from gravitational collapse. In this traditional view, the magnetic field lines in the corona must have a dipped geometry so that the field forms a hammock structure in which prominence material can rest. There are several problems with this static scenario, however. First, there is little observational evidence for highly dipped or twisted fields in prominences except during eruptions (S. Martin and O. Engvold, personal communication). Second, most prominences are very dynamic over much if not all of their extent, obviating the need to support predominantly static condensations. On the other hand, our condensation studies have shown that condensations that form on arched field lines are less massive and shorter lived than those formed on flat or shallowly dipped field lines. Therefore, long, low-lying field lines should carry the bulk of the dynamic prominence mass, as is consistent with today's high-cadence, high-resolution observations of the cool plasma tracing the filament field.

We have developed a sheared 3D arcade model for the origin of these long, low-lying prominence field lines (see Antiochos, Dahlburg, & Klimchuk 1994 and Devore & Antiochos 2000 in Bibliography for details). Our straightforward model has two key ingredients. First, the magnetic field is fully 3D, with significant variations in photospheric flux along the PIL. Second, the field is strongly sheared only near the PIL, as observed. Field lines with footpoints far from the neutral line are almost potential. As a consequence of this spatial variation in both the photospheric flux and shear, coronal fluxtubes tend to expand more strongly near their footpoints than near their midpoints and, thereby, acquire a dipped geometry. Observations suggest that the Sun creates filament channels through some not-yet-understood process involving flux emergence, cancellation, and/or post-emergence subsurface motions. In our simulations we create a filament channel by imposing a slow photospheric shear-flow localized at the PIL, whose appearance is consistent with our recent studies of Flux Emergence. Figure 7 (a 16 MB Quicktime movie) shows the magnetic-field evolution of this system from an initially potential state through extensive shearing and relaxation to a force-free state during a 3D MHD sheared-arcade simulation.

Some prominences appear to be composed of more than a single sheared arcade. Observations show that elongated filaments can grow by colliding and fusing with adjacent filament segments, producing a more extended, interlinked structure. We have demonstrated how this growth occurs, within the sheared arcade model, by simulating the evolving interaction and reconnection between adjacent sheared bipoles displaced along a common PIL. Figures 8 and 9 show the initial and final states of this simulation, respectively. The length, shear, and helicity of the two individual filaments that form initially are combined in the fused configuration that develops when the magnetic fields reconnect (DeVore, Antiochos, & Aulanier 2004, in preparation).

Return to Welcome.

 

[BigRay]

The language of physics is mathematics. In order to study physics seriously, one needs to learn mathematics that took generations of brilliant people centuries to work out. Algebra, for example, was cutting-edge mathematics when it was being developed in Baghdad in the 9th century. But today it's just the first step along the journey.
Algebra
Algebra provides the first exposure to the use of variables and constants, and experience manipulating and solving linear equations of the form y = ax + b and quadratic equations of the form y = ax2+bx+c.
Geometry
Geometry at this level is two-dimensional Euclidean geometry, Courses focus on learning to reason geometrically, to use concepts like symmetry, similarity and congruence, to understand the properties of geometric shapes in a flat, two-dimensional space.
Trigonometry
Trigonometry begins with the study of right triangles and the Pythagorean theorem. The trigonometric functions sin, cos, tan and their inverses are introduced and clever identities between them are explored.
Calculus (single variable)
Calculus begins with the definition of an abstract functions of a single variable, and introduces the ordinary derivative of that function as the tangent to that curve at a given point along the curve. Integration is derived from looking at the area under a curve,which is then shown to be the inverse of differentiation.
Calculus (multivariable)
Multivariable calculus introduces functions of several variables f(x,y,z...), and students learn to take partial and total derivatives. The ideas of directional derivative, integration along a path and integration over a surface are developed in two and three dimensional Euclidean space.
Analytic Geometry
Analytic geometry is the marriage of algebra with geometry. Geometric objects such as conic sections, planes and spheres are studied by the means of algebraic equations. Vectors in Cartesian, polar and spherical coordinates are introduced.
Linear Algebra
In linear algebra, students learn to solve systems of linear equations of the form ai1 x1 + ai2 x2 + ... + ain xn = ci and express them in terms of matrices and vectors. The properties of abstract matrices, such as inverse, determinant, characteristic equation, and of certain types of matrices, such as symmetric, antisymmetric, unitary or Hermitian, are explored.
Ordinary Differential Equations
This is where the physics begins! Much of physics is about deriving and solving differential equations. The most important differential equation to learn, and the one most studied in undergraduate physics, is the harmonic oscillator equation, ax'' + bx' + cx = f(t), where x' means the time derivative of x(t).
Partial Differential Equations
For doing physics in more than one dimension, it becomes necessary to use partial derivatives and hence partial differential equations. The first partial differential equations students learn are the linear, separable ones that were derived and solved in the 18th and 19th centuries by people like Laplace, Green, Fourier, Legendre, and Bessel.
Methods of approximation
Most of the problems in physics can't be solved exactly in closed form. Therefore we have to learn technology for making clever approximations, such as power series expansions, saddle point integration, and small (or large) perturbations.
Probability and statistics
Probability became of major importance in physics when quantum mechanics entered the scene. A course on probability begins by studying coin flips, and the counting of distinguishable vs. indistinguishable objects. The concepts of mean and variance are developed and applied in the cases of Poisson and Gaussian statistics.

 

[BigRay]

1500 Babylonians establish the metric of flat 2-dimensional space by observation, in their efforts to keep track of land for legal and economic purposes.
-518 Pythagoras, a Greek educated by mystics in Egypt and Babylon, founds community of men and women calling themselves mathematikoi, in southern Italy. They believe that reality is in essence mathematical. Pythagoras noted that vibrating lyre strings with harmonious notes have lengths that are proportional by a whole number. The Pythagorean theorem proves by reasoning what the Babylonians figured out by measurement 1000 years earlier.
-387 Plato, after traveling to Italy and learning about the Pythagoreans, founds his Academy in Athens, and continues to develop the idea that reality must be expressible in mathematical terms. But Athens at that time has developed a notoriously misogynist culture. Unlike his role model Pythagoras, whose school developed many women mathematikoi, Plato does not allow women to participate.
-300 Euclid of Alexandria, a gifted teacher, produces Elements, one of the top mathematics textbooks of recorded history, which organizes the existing Mediterranean understanding of geometry into a coherent logical framework.
-225 Ionian mathematician Apollonius writes Conics, and introduces the terms ellipse, parabola and hyperbola to describe conic sections.
-140 Nicaean mathematician and astronomer Hipparchus develops what will be known as trigonometry.
150 The Almagest by Alexandrian astronomer and mathematician Claudius Ptolemy asserts that the Sun and planets orbit around the Earth in perfect circles. Ptolemy's work is so influential that will become official church doctrine when the Christians later come to rule Europe.
415 As a glorious 2000 years of ancient Mediterranean mathematics and science comes to a close, Hypatia of Alexandria, a renowned teacher, mathematician, astronomer, and priestess of Isis, is kidnapped from a public religious procession and brutally murdered by a mob of angry Christian monks.
628 Hindu mathematician-astronomer Brahmagupta writes Brahma- sphuta- siddhanta (The Opening of the Universe). Hindu mathematicians develop numerals and start investigating number theory.
830 The spread of Islam leads to the spread of written Arabic language. As ancient Greek and Hindu works are translated into Arabic, a culture of mathematics and astronomy develops. The peak of this cultural flowering is represented by Arabic mathematician Al-Khworizmi, working at the House of Wisdom in Baghdad, who develops what will be known as algebra in his work Hisab al-jabr w'al-muqabala.
1070 Iranian poet, mathematician and astronomer Omar Khayyam begins his Treatise on Demonstration of Problems of Algebra, classifying cubic equations that could be solved by conic sections. Khayyam was such a brilliant poet that history has nearly forgotten that he was also a brilliant scientist and mathematician. The moving finger writes...
1120 Adelard of Bath translates works of Euclid and Al-Khworizmi into Latin and introduces them to European scholars.
1482 Euclid's Elements is published using the revolutionary new technology of the printing press, leading to a revolution in education and scholarship as information becomes more difficult for authorities to control.
1543 Copernicus publishes De revolutionibus orbium coelestium (On the revolutions of the heavenly spheres) asserting that the Earth and planets revolve about the Sun. The Catholic Church has accorded an official holy status to Ptolemy's geocentric Universe. Copernicus avoids prosecution as a heretic by waiting until the end of his own life to publish his controversial claims.
1589 Pisa University mathematics instructor Galileo Galilei studies the motion of objects and begins a book De Motu (On Motion) which he never finishes.
1602 Galileo observes that the period of a swinging pendulum is independent of the amplitude of the swing.
1609 Johannes Kepler claims in the journal Astronomia Nova that the orbit of Mars is an ellipse with the Sun at one focus, and sweeps out equal areas in equal time. He will later generalize these into his famous Three Laws of Planetary Motion.
1609 Galileo makes his first telescope. His observations of the moon show that it looks like a very large lumpy rock, not a divinely smooth and perfect shining Platonic heavenly orb. This discovery has enormously distressing cultural reverberations for Western culture and religion.
1614 Scottish theologian John Napier, who does mathematics as a hobby, publishes his discovery of the logarithm in his work Mirifici logarithmorum canonis descriptio.
1615 Kepler's mother, Frau Katharina Kepler, is accused of witchcraft by a local prostitute. European witch hunting was at its peak during Kepler's career, and witch hunting was supported by all levels of society, including secular officials and intellectuals in universities. Kepler spends the next several years making legal appeals and hiding his mother from legal authorities seeking to torture her into confessing to witchcraft. Examining an accused witch ad torturam was a standard court procedure during this era.
1620 Under court order, Kepler's mother is kidnapped in the middle of the night from her daughter's home and taken to prison. Kepler spends the next year appealing to the duke of Württemberg to prevent his imprisoned mother from being examined ad torturam.
1621 On September 28, Katharina Kepler is taken from her prison cell into the torture room, shown the instruments of torture and ordered to confess. She replies "Do with me what you want. Even if you were to pull one vein after another out of my body, I would have nothing to admit," and says the Lord's Prayer. She is taken back to prison. She is freed on October 4 upon order of the duke, who rules that her refusal to confess under threat of torture proves her innocence. He also orders her accusers to pay the cost of her trial and imprisonment.
1622 After having spent most of the last seven years under the legal threat of imminent torture, Katharina Kepler dies on April 13, still being threatened with violence from those who insist she is a witch.
1624 Pope Urban VIII promises Galileo that he is allowed write about Copernican heliocentrism if he treats it as an abstract proposition.
1628 Kepler uses Napier's logarithms to compute a set of astronomical tables, the Rudolphine Tables, whose accuracy is so impressive that it leads to the quiet acceptance of the heliocentric solar system by everyone in the shipping industry.
1629 Basque mathematician Pierre de Fermat, the founder of modern number theory, begins his brilliant career by reconstructing the work of Apollonius on conic sections . Fermat and Descartes pioneer the application of algebraic methods to solving problems in geometry.
1632 Galileo publishes Dialogue concerning the two greatest world systems, which argues convincingly for the Copernican view that the Earth and planets revolve around the Sun.
1633 The Inquisition calls Galieo to Rome to answer charges of heresy against the Catholic Church.
1637 Descartes publishes his revolutionary Discours de la m�thode (Discourse on Method) containing three essays on the use of reason to search for the truth. In the third essay Descartes describes analytic geometry, and uses the letters (x,y,z) for the coordinate system that will later bear his name.
1642 Galileo dies at his villa in Florence, still under house arrest from charges of heresy.
1663 Cambridge mathematician Isaac Barrow delivers lectures on modern methods of computing tangents that inspire his student Isaac Newton towards developing calculus
1665 Newton's "miraculous years" in math and physics, when he discovers the derivative, which he sees as a ratio of velocities called fluxions, and the integral, which he sees as a fluent of the fluxions. Newton shows that the fluent and fluxion are inversely related, a result now called the Fundamental Theorem of Calculus. Newton also develops his ideas on optics and gravitation. He tries to publish his work in 1671, but the publisher goes bankrupt.
1683 Jacob Bernoulli, who studied mathematics and astronomy against the wishes of his career-minded parents, teaches Newtonian mechanics at the University of Basel, and turns mathematical physics into a family business.
1684 Leibniz publishes the beginning of his work on differential and integral calculus. He discovers the Fundamental Theorem of Calculus in his own way. Leibniz originates most of the current calculus notation including the integral sign. He portrays an integral as a sum of infinitesimals, a concept rejected by Newton.
1687 Newton publishes Principia Mechanica after Edmund Halley convinces Newton to write up his alleged proof that an inverse square force law leads to elliptical orbits. Newton's Laws of Motion and Law of Gravitation lead to the development of theoretical physics itself. This event marks a permanent change in the relationship between human beings and the Universe.
1693 Newton has a nervous breakdown after his close companion Fatio De Duillier becomes ill and has to return to Switzerland.
1696

Brachistochrone problem solved by Jacob and Johann Bernoulli, an early result in the calculus of variations.
1712 Thanks to a campaign waged by Newton, a commission appointed by Royal Society of London President Isaac Newton rules that Leibniz is guilty of plagiarism again

 

[BigRay]

Chaos Theory: A Brief Introduction
What exactly is chaos? The name "chaos theory" comes from the fact that the systems that the theory describes are apparently disordered, but chaos theory is really about finding the underlying order in apparently random data.

When was chaos first discovered? The first true experimenter in chaos was a meteorologist, named Edward Lorenz. In 1960, he was working on the problem of weather prediction. He had a computer set up, with a set of twelve equations to model the weather. It didn't predict the weather itself. However this computer program did theoretically predict what the weather might be.

One day in 1961, he wanted to see a particular sequence again. To save time, he started in the middle of the sequence, instead of the beginning. He entered the number off his printout and left to let it run.

When he came back an hour later, the sequence had evolved differently. Instead of the same pattern as before, it diverged from the pattern, ending up wildly different from the original. (See figure 1.) Eventually he figured out what happened. The computer stored the numbers to six decimal places in its memory. To save paper, he only had it print out three decimal places. In the original sequence, the number was .506127, and he had only typed the first three digits, .506.

[Figure 1]
By all conventional ideas of the time, it should have worked. He should have gotten a sequence very close to the original sequence. A scientist considers himself lucky if he can get measurements with accuracy to three decimal places. Surely the fourth and fifth, impossible to measure using reasonable methods, can't have a huge effect on the outcome of the experiment. Lorenz proved this idea wrong.

This effect came to be known as the butterfly effect. The amount of difference in the starting points of the two curves is so small that it is comparable to a butterfly flapping its wings.

The flapping of a single butterfly's wing today produces a tiny change in the state of the atmosphere. Over a period of time, what the atmosphere actually does diverges from what it would have done. So, in a month's time, a tornado that would have devastated the Indonesian coast doesn't happen. Or maybe one that wasn't going to happen, does. (Ian Stewart, Does God Play Dice? The Mathematics of Chaos, pg. 141)

This phenomenon, common to chaos theory, is also known as sensitive dependence on initial conditions. Just a small change in the initial conditions can drastically change the long-term behavior of a system. Such a small amount of difference in a measurement might be considered experimental noise, background noise, or an inaccuracy of the equipment. Such things are impossible to avoid in even the most isolated lab. With a starting number of 2, the final result can be entirely different from the same system with a starting value of 2.000001. It is simply impossible to achieve this level of accuracy - just try and measure something to the nearest millionth of an inch!

From this idea, Lorenz stated that it is impossible to predict the weather accurately. However, this discovery led Lorenz on to other aspects of what eventually came to be known as chaos theory.

Lorenz started to look for a simpler system that had sensitive dependence on initial conditions. His first discovery had twelve equations, and he wanted a much more simple version that still had this attribute. He took the equations for convection, and stripped them down, making them unrealistically simple. The system no longer had anything to do with convection, but it did have sensitive dependence on its initial conditions, and there were only three equations this time. Later, it was discovered that his equations precisely described a water wheel.

At the top, water drips steadily into containers hanging on the wheel's rim. Each container drips steadily from a small hole. If the stream of water is slow, the top containers never fill fast enough to overcome friction, but if the stream is faster, the weight starts to turn the wheel. The rotation might become continuous. Or if the stream is so fast that the heavy containers swing all the way around the bottom and up the other side, the wheel might then slow, stop, and reverse its rotation, turning first one way and then the other. (James Gleick, Chaos - Making a New Science, pg. 29)

[Figure 2] The equations for this system also seemed to give rise to entirely random behavior. However, when he graphed it, a surprising thing happened. The output always stayed on a curve, a double spiral. There were only two kinds of order previously known: a steady state, in which the variables never change, and periodic behavior, in which the system goes into a loop, repeating itself indefinitely. Lorenz's equations were definitely ordered - they always followed a spiral. They never settled down to a single point, but since they never repeated the same thing, they weren't periodic either. He called the image he got when he graphed the equations the Lorenz attractor. (See figure 2)

In 1963, Lorenz published a paper describing what he had discovered. He included the unpredictability of the weather, and discussed the types of equations that caused this type of behavior. Unfortunately, the only journal he was able to publish in was a meteorological journal, because he was a meteorologist, not a mathematician or a physicist. As a result, Lorenz's discoveries weren't acknowledged until years later, when they were rediscovered by others. Lorenz had discovered something revolutionary; now he had to wait for someone to discover him.

Another system in which sensitive dependence on initial conditions is evident is the flip of a coin. There are two variables in a flipping coin: how soon it hits the ground, and how fast it is flipping. Theoretically, it should be possible to control these variables entirely and control how the coin will end up. In practice, it is impossible to control exactly how fast the coin flips and how high it flips. It is possible to put the variables into a certain range, but it is impossible to control it enough to know the final results of the coin toss.

A similar problem occurs in ecology, and the prediction of biological populations. The equation would be simple if population just rises indefinitely, but the effect of predators and a limited food supply make this equation incorrect. The simplest equation that takes this into account is the following:

next year's population = r * this year's population * (1 - this year's population)

In this equation, the population is a number between 0 and 1, where 1 represents the maximum possible population and 0 represents extinction. R is the growth rate. The question was, how does this parameter affect the equation? The obvious answer is that a high growth rate means that the population will settle down at a high population, while a low growth rate means that the population will settle down to a low number. This trend is true for some growth rates, but not for every one.

One biologist, Robert May, decided to see what would happen to the equation as the growth rate value changes. At low values of the growth rate, the population would settle down to a single number. For instance, if the growth rate value is 2.7, the population will settle down to .6292. As the growth rate increased, the final population would increase as well. Then, something weird happened. [Figure 3] As soon as the growth rate passed 3, the line broke in two. Instead of settling down to a single population, it would jump between two different populations. It would be one value for one year, go to another value the next year, then repeat the cycle forever. Raising the growth rate a little more caused it to jump between four different values. As the parameter rose further, the line bifurcated (doubled) again. The bifurcations came faster and faster until suddenly, chaos appeared. Past a certain growth rate, it becomes impossible to predict the behavior of the equation. However, upon closer inspection, it is possible to see white strips. Looking closer at these strips reveals little windows of order, where the equation goes through the bifurcations again before returning to chaos. This self-similarity, the fact that the graph has an exact copy of itself hidden deep inside, came to be an important aspect of chaos.

An employee of IBM, Benoit Mandelbrot was a mathematician studying this self-similarity. One of the areas he was studying was cotton price fluctuations. No matter how the data on cotton prices was analyzed, the results did not fit the normal distribution. Mandelbrot eventually obtained all of the available data on cotton prices, dating back to 1900. When he analyzed the data with IBM's computers, he noticed an astonishing fact:

The numbers that produced aberrations from the point of view of normal distribution produced symmetry from the point of view of scaling. Each particular price change was random and unpredictable. But the sequence of changes was independent on scale: curves for daily price changes and monthly price changes matched perfectly. Incredibly, analyzed Mandelbrot's way, the degree of variation had remained constant over a tumultuous sixty-year period that saw two World Wars and a depression. (James Gleick, Chaos - Making a New Science, pg. 86)

Mandelbrot analyzed not only cotton prices, but many other phenomena as well. At one point, he was wondering about the length of a coastline. A map of a coastline will show many bays. However, measuring the length of a coastline off a map will miss minor bays that were too small to show on the map. Likewise, walking along the coastline misses microscopic bays in between grains of sand. No matter how much a coastline is magnified, there will be more bays visible if it is magnified more.

One mathematician, Helge von Koch, captured this idea in a mathematical construction called the Koch curve. To create a Koch curve, imagine an equilateral triangle. To the middle third of each side, add another equilateral triangle. [Figure 4] Keep on adding new triangles to the middle part of each side, and the result is a Koch curve. (See figure 4) A magnification of the Koch curve looks exactly the same as the original. It is another self-similar figure.

The Koch curve brings up an interesting paradox. Each time new triangles are added to the figure, the length of the line gets longer. However, the inner area of the Koch curve remains less than the area of a circle drawn around the original triangle. Essentially, it is a line of infinite length surrounding a finite area.

To get around this difficulty, mathematicians invented fractal dimensions. Fractal comes from the word fractional. The fractal dimension of the Koch curve is somewhere around 1.26. A fractional dimension is impossible to conceive, but it does make sense. The Koch curve is rougher than a smooth curve or line, which has one dimension. Since it is rougher and more crinkly, it is better at taking up space. However, it's not as good at filling up space as a square with two dimensions is, since it doesn't really have any area. So it makes sense that the dimension of the Koch curve is somewhere in between the two.

Fractal has come to mean any image that displays the attribute of self-similarity. The bifurcation diagram of the population equation is fractal. The Lorenz Attractor is fractal. The Koch curve is fractal.

During this time, scientists found it very difficult to get work published about chaos. Since they had not yet shown the relevance to real-world situations, most scientists did not think the results of experiments in chaos were important. As a result, even though chaos is a mathematical phenomenon, most of the research into chaos was done by people in other areas, such as meteorology and ecology. The field of chaos sprouted up as a hobby for scientists working on problems that maybe had something to do with it.

Later, a scientist by the name of Feigenbaum was looking at the bifurcation diagram again. He was looking at how fast the bifurcations come. He discovered that they come at a constant rate. He calculated it as 4.669. In other words, he discovered the exact scale at which it was self-similar. Make the diagram 4.669 times smaller, and it looks like the next region of bifurcations. He decided to look at other equations to see if it was possible to determine a scaling factor for them as well. Much to his surprise, the scaling factor was exactly the same. Not only was this complicated equation displaying regularity, the regularity was exactly the same as a much simpler equation. He tried many other functions, and they all produced the same scaling factor, 4.669.

This was a revolutionary discovery. He had found that a whole class of mathematical functions behaved in the same, predictable way. This universality would help other scientists easily analyze chaotic equations. Universality gave scientists the first tools to analyze a chaotic system. Now they could use a simple equation to predict the outcome of a more complex equation.

Many scientists were exploring equations that created fractal equations. The most famous fractal image is also one of the most simple. It is known as the Mandelbrot set (pictures of the mandelbrot set). The equation is simple: z=z2+c. To see if a point is part of the Mandelbrot set, just take a complex number z. Square it, then add the original number. Square the result, then add the original number. Repeat that ad infinitum, and if the number keeps on going up to infinity, it is not part of the Mandelbrot set. If it stays down below a certain level, it is part of the Mandelbrot set. The Mandelbrot set is the innermost section of the picture, and each different shade of gray represents how far out that particular point is. One interesting feature of the Mandelbrot set is that the circular humps match up to the bifurcation graph. The Mandelbrot fractal has the same self-similarity seen in the other equations. In fact, zooming in deep enough on a Mandelbrot fractal will eventually reveal an exact replica of the Mandelbrot set, perfect in every detail.

Fractal structures have been noticed in many real-world areas, as well as in mathematician's minds. Blood vessels branching out further and further, the branches of a tree, the internal structure of the lungs, graphs of stock market data, and many other real-world systems all have something in common: they are all self-similar.

Scientists at UC Santa Cruz found chaos in a dripping water faucet. By recording a dripping faucet and recording the periods of time, they discovered that at a certain flow velocity, the dripping no longer occurred at even times. When they graphed the data, they found that the dripping did indeed follow a pattern.

The human heart also has a chaotic pattern. The time between beats does not remain constant; it depends on how much activity a person is doing, among other things. Under certain conditions, the heartbeat can speed up. Under different conditions, the heart beats erratically. It might even be called a chaotic heartbeat. The analysis of a heartbeat can help medical researchers find ways to put an abnormal heartbeat back into a steady state, instead of uncontrolled chaos.

Researchers discovered a simple set of three equations that graphed a fern. This started a new idea - perhaps DNA encodes not exactly where the leaves grow, but a formula that controls their distribution. DNA, even though it holds an amazing amount of data, could not hold all of the data necessary to determine where every cell of the human body goes. However, by using fractal formulas to control how the blood vessels branch out and the nerve fibers get created, DNA has more than enough information. It has even been speculated that the brain itself might be organized somehow according to the laws of chaos.

Chaos even has applications outside of science. Computer art has become more realistic through the use of chaos and fractals. Now, with a simple formula, a computer can create a beautiful, and realistic tree. Instead of following a regular pattern, the bark of a tree can be created according to a formula that almost, but not quite, repeats itself.

Music can be created using fractals as well. Using the Lorenz attractor, Diana S. Dabby, a graduate student in electrical engineering at the Massachusetts Institute of Technology, has created variations of musical themes. ("Bach to Chaos: Chaotic Variations on a Classical Theme", Science News, Dec. 24, 1994) By associating the musical notes of a piece of music like Bach's Prelude in C with the x coordinates of the Lorenz attractor, and running a computer program, she has created variations of the theme of the song. Most musicians who hear the new sounds believe that the variations are very musical and creative.

Chaos has already had a lasting effect on science, yet there is much still left to be discovered. Many scientists believe that twentieth century science will be known for only three theories: relativity, quantum mechanics, and chaos. Aspects of chaos show up everywhere around the world, from the currents of the ocean and the flow of blood through fractal blood vessels to the branches of trees and the effects of turbulence. Chaos has inescapably become part of modern science. As chaos changed from a little-known theory to a full science of its own, it has received widespread publicity. Chaos theory has changed the direction of science: in the eyes of the general public, physics is no longer simply the study of subatomic particles in a billion-dollar particle accelerator, but the study of chaotic systems and how they work.

 

[BigRay]

nsects are invertebrates that are taxonomically referred to as the class Insecta. They are the most numerous and most widespread terrestrial taxon within the phylum Arthropoda. Insects are the most diverse group of animals on the earth, with around 925,000 species described—more than all other animal groups combined. Insects may be found in nearly all environments on the planet, although only a small number of species have adapted to life in the oceans where crustaceans tend to predominate.

There are approximately 5,000 dragonfly species, 2,000 praying mantis, 20,000 grasshopper, 170,000 butterfly and moth, 120,000 fly, 82,000 true bug, 350,000 beetle, and 110,000 bee and ant species described to date. Estimates of the total number of current species, including those not yet known to science, range from two million to thirty million, with most authorities favoring a figure midway between these extremes. Adult modern insects range in size from 555 mm (see Phobaeticus serratipes) to 0.139 mm (see Dicopomorpha echmepterygis)

The study of insects (from Latin insect, meaning "cut into sections") is called entomology, from the Greek εντομος, also meaning "cut into sections" [1].
Green bottle fly
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Green bottle fly
Contents
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* 1 Relationship to other arthropods
* 2 Morphology and development
o 2.1 Development
* 3 Behavior
* 4 Roles in the environment and human society
* 5 Taxonomy
* 6 Evolution
* 7 References
* 8 Quotes
* 9 See also
* 10 External links
* 11 Gallery

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Relationship to other arthropods
Chinese mantis
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Chinese mantis

Other terrestrial arthropods, such as centipedes, millipedes, scorpions and spiders, are sometimes confused with insects due to the fact that both have similar body plans, sharing (as do all arthropods) a jointed exoskeleton. However these do not have the important feature of having six legs.

Within the subphylum Hexapoda, a few groups such as springtails (Collembola), are often treated as insects; however some authors treat them as distinct from the insects in having a different evolutionary origin. This may also be that case for the rest of the members of the Entognatha; Protura and Diplura.

The true insects, those of the Class Insecta, are distinguished from all other arthropods in part by having ectognathous, or exposed, mouthparts and eleven (11) abdominal segments. The true insects are therefore sometimes also referred to as the Ectognatha. Many insect groups are winged as adults. The exopterygote part of the Neoptera are sometimes divided into Orthopteroida (cerci present) and Hemipteroida (cerci absent), also called lower and higher Exopterygota.


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Morphology and development
Insect anatomy A- Head B- Thorax C- Abdomen 1. antenna 2. ocelli (lower) 3. ocelli (upper) 4. compound eye 5. brain (cerebral ganglia) 6. prothorax 7. dorsal artery 8. tracheal tubes (trunk with spiracle) 9. mesothorax 10. metathorax 11. forewing 12. hindwing 13. mid-gut (stomach) 14. heart 15. ovary 16. hind-gut (intestine, rectum & anus) 17. anus 18. vagina 19. nerve chord (abdominal ganglia) 20. Malpighian tubes 21. pillow 22. claws 23. tarsus 24. tibia 25. femur 26. trochanter 27. fore-gut (crop, gizzard) 28. thoracic ganglion 29. coxa 30. salivary gland 31. subesophageal ganglion 32. mouthparts
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Insect anatomy
A- Head B- Thorax C- Abdomen
1. antenna
2. ocelli (lower)
3. ocelli (upper)
4. compound eye
5. brain (cerebral ganglia)
6. prothorax
7. dorsal artery
8. tracheal tubes (trunk with spiracle)
9. mesothorax
10. metathorax
11. forewing
12. hindwing
13. mid-gut (stomach)
14. heart
15. ovary
16. hind-gut (intestine, rectum & anus)
17. anus
18. vagina
19. nerve chord (abdominal ganglia)
20. Malpighian tubes
21. pillow
22. claws
23. tarsus
24. tibia
25. femur
26. trochanter
27. fore-gut (crop, gizzard)
28. thoracic ganglion
29. coxa
30. salivary gland
31. subesophageal ganglion
32. mouthparts

Insects range in size from less than a millimeter to over 18 centimeters (some walkingsticks) in length. Insects possess segmented bodies supported by an exoskeleton, a hard outer covering made mostly of chitin. The body is divided into a head, a thorax, and an abdomen. The head supports a pair of sensory antennae, a pair of compound eyes, and mouth parts. The thorax has six legs (one pair per segment) and wings (if present in the species). The abdomen (made up of eleven segments some of which may be reduced or fused) has respiratory, excretory and reproductive structures.

Their nervous system can be divided into a brain and a ventral nerve cord. The head capsule (made up of six fused segments) has six pairs of ganglia. The first three pairs are fused into the brain, while the three following pairs are fused into a structure called the subesophageal ganglion.

The thoracic segments have one ganglion on each side, which are connected into a pair, one pair per segment. This arrangement is also seen in the abdomen but only in the first eight segments. Many species of insects have reduced numbers of ganglia due to fusion or reduction. Some cockroaches have just six ganglia in the abdomen, whereas the wasp Vespa crabro has only two in the thorax and three in the abdomen. And some like the house fly Musca domestica have fused all the body ganglia into a single large thoracic ganglion.

Insects have a complete digestive system. That is, their digestive system consists basically of a tube that runs from mouth to anus, contrasting with the incomplete digestive systems found in many simpler invertebrates. The excretory system consists of Malpighian tubules for the removal of nitrogenous wastes and the hindgut for osmoregulation. At the end of the hindgut, insects are able to reabsorb water along with potassium and sodium ions. Therefore, insects don't usually excrete water with their feces, allowing storage of water in the body. This process of reabsorption enables them to withstand hot, dry environments.

Most insects have two pairs of wings located on the second and third thoracic segments. Insects are the only invertebrates to have developed flight, and this has played an important part in their success. The winged insects, and their wingless relatives, make up the subclass Pterygota. Insect flight is not very well understood, relying heavily on turbulent aerodynamic effects. The primitive insect groups use muscles that act directly on the wing structure. The more advanced groups making up the Neoptera have foldable wings and their muscles act on the thorax wall and power the wings indirectly. These muscles are able to contract without nerve impulses allowing them to beat faster (see Insect flight).

Their outer skeleton, the cuticle, is made up of two layers; the epicuticle which is a thin and waxy water resistant outer layer and contains no chitin, and another layer under it called the procuticle. This is chitinous and much thicker than the epicuticle and has two layers. The outer being the exocuticle while the inner is the endocuticle. The tough and flexible endocuticle is built from numerous layers of fibrous chitin and proteins, criss-crossing each others in a sandwich pattern, while the exocuticle is sclerotized.

Insects use tracheal respiration with openings on the sides of the thorax and abdomen called spiracles leading to the tubular tracheal system. Air reaches internal tissues via a network of branches from the tracheal system. There is usually one pair of spiracles per segment. There can be up to 8 abdominal segments with spiracles and upto 2 thoracic segments (restricted to the mesothorax and metathorax). Some groups have reduced numbers of spiracles with the hoverflies having none on their abdomen. There is a physical limit to the pressure that the walls of the tracheal tubes can withstand without collapsing, even though they are stiffened by bands of chitin, and this is one of the reasons why insects are relatively small. The spiracles have muscle controlled valves, enabling the insects to avoid drowning in water or to prevent desiccation. The spiracles often have hairs that help filter the air entering them.

Some insect groups such as the Chironomidae or "blood worms" have true respiratory pigments such as hemoglobin in their blood during their larval stage. Here the trachea are often reduced as their body can absorb oxygen directly from the water, allowing them to live in bottom mud where the oxygen levels are low.

In certain types of water bugs the three pairs of the spiracles are covered by a pressure-sensitive membrane that help them sense their position in water. The last abdominal spiracle and associated trachea of certain Lepidopteran caterpillars are modified into a tracheal lung adapted for hemocyte gas exchange. Short tracheoles from this trachea ends in knots within the tracheole cell basement membrane. Since they do not supply any cellular tissue, it seems most likely that they are supplying the hemocytes with oxygen.

The Madagascar hissing cockroach uses certain spiracles to forcibly expel air to create a loud hissing sound when threatened.

A diffuse tissue called a fat body is found in the abdominal haemocoel of some insects. This is believed to help in energy storage and metabolic processes and acts like a liver for the insects.

The circulatory system of insects, like that of other arthropods, is open: the heart, which is little more than a perforated muscular tube along the dorsal midline, pumps the hemolymph to open spaces surrounding the internal organs; when the heart relaxes, the hemolymph seeps back into the heart.

Like some other invertebrates, insects cannot synthesise cholesterol and must receive it from the diet. With very few exceptions, they also require long-chain fatty acids in their diet. Lack of these fatty acids affects their development leading to delayed maturity or deformations.
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Development

Most insects hatch from eggs, but others are ovoviviparous or viviparous, and all undergo a series of moults as they develop and grow in size. This manner of growth is necessitated by the inelastic exoskeleton. Moulting is a process by which the individual escapes the confines of the exoskeleton in order to increase in size, then grows a new and larger outer covering. In some insects, the young are called nymphs and are similar in form to the adults except that the wings are not developed until the adult stage. This is called incomplete metamorphosis and insects showing this are termed as Hemimetabolous. Holometabolous insects show Complete metamorphosis, which distinguishes the Endopterygota and includes many of the most successful insect groups. In these species, an egg hatches to produce a larva, which is generally worm-like in form, and can be divided into five different forms; eruciform (caterpillar-like), scarabaeiform (grublike), campodeiform (elongated, flattened, and active), elateriform (wireworm-like) and vermiform (maggot-like). The larva grows and eventually becomes a pupa, a stage sealed within a cocoon or chrysalis in some species. There are three types of pupae; obtect (the pupa is compact with the legs and other appendages enclosed), exarate (where the pupa has the legs and other appendages free and extended) and coarctate (where the pupa develops inside the larval skin). In the pupal stage, the insect undergoes considerable change in form to emerge as an adult, or imago. Butterflies are an example of an insect that undergoes complete metamorphosis. Some insects have even evolved hypermetamorphosis.

Some insects (parastic wasps) show polyembryony where a single fertilized egg can divide into many and in some cases thousands of separate embryos. Other developmental and reproductive variations include haplodiploidy, polymorphism, paedomorphosis (metathetely and prothetely), sexual dimorphism, parthenogenesis and more rarely hermaphroditism.
A butterfly is the adult stage of an insect with complete metamorphosis. This species is Anartia amathea.
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A butterfly is the adult stage of an insect with complete metamorphosis. This species is Anartia amathea.
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Behavior
Flies attracted to an incandescent light bulb
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Flies attracted to an incandescent light bulb

Many insects possess very sensitive organs of perception. Some insects such as bees can see in the ultraviolet spectrum while male moths can detect the pheromones of female moths over distances of many kilometers.

Many insects also have a well-developed number sense, especially among the solitary wasps. The mother wasp lays her eggs in individual cells and provides each egg with a number of live caterpillars on which the young feed when hatched. Some species of wasp always provide five, others twelve, and others as high as twenty-four caterpillars per cell. The number of caterpillars is different among species, but it is always the same for each sex of eggs. The male solitary wasp in the genus Eumenes is smaller than the female, so the mother supplies him with only five caterpillars; the larger female receives ten caterpillars in her cell. She can in other words distinguish between both the numbers five and ten in the caterpillars she is providing and which cell contains a male or a female.

Social insects, such as the ant and the bee, are the most familiar species of eusocial animal. They live together in large well-organized colonies that are so tightly integrated and genetically similar that the colonies are sometimes considered superorganisms.
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Roles in the environment and human society
Aedes aegypti, a parasite, and vector of dengue fever and yellow fever
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Aedes aegypti, a parasite, and vector of dengue fever and yellow fever

Many insects are considered pests by humans. Insects commonly regarded as pests include those that are parasitic (mosquitoes, lice, bedbugs), transmit diseases (mosquitos, flies), damage structures (termites), or destroy agricultural goods (locusts, weevils). Many entomologists are involved in various forms of pest control, often using insecticides, but more and more relying on methods of biocontrol.

Although pest insects attract the most attention, many insects are beneficial to the environment and to humans. Some pollinate flowering plants (for example wasps, bees, butterflies, ants). Pollination is a trade between plants that need to reproduce, and pollinators that receive rewards of nectar and pollen. A serious environmental problem today is the decline of populations of pollinator insects, and a number of species of insects are now cultured primarily for pollination management in order to have sufficient pollinators in the field, orchard or greenhouse at bloom time.

Insects also produce useful substances such as honey, wax, lacquer and silk. Honeybees have been cultured by humans for thousands of years for honey, although contracting for crop pollination is becoming more significant for beekeepers. The silkworm has greatly affected human history, as silk-driven trade established relationships between China and the rest of the world. Fly larvae (maggots) were formerly used to treat wounds to prevent or stop gangrene, as they would only consume dead flesh. This treatment is finding modern usage in some hospitals. Adult insects such as crickets, and insect larvae of various kinds are also commonly used as fishing bait.
Lubber grasshopper
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Lubber grasshopper

In some parts of the world, insects are used for human food ("Entomophagy"), while being a taboo in other places. There are proponents of developing this use to provide a major source of protein in human nutrition. Since it is impossible to entirely eliminate pest insects from the human food chain, insects already are present in many foods, especially grains. Most people do not realize that food laws in many countries do not prohibit insect parts in food, but rather limit the quantity. According to cultural materialist anthropologist Marvin Harris, the eating of insects is taboo in cultures that have protein sources that require less work, like farm birds or cattle.

Many insects, especially beetles, are scavengers, feeding on dead animals and fallen trees, recycling the biological materials into forms found useful by other organisms. The ancient Egyptian religion adored beetles and represented them as scarabeums.

Although mostly unnoticed by most humans, the most useful of all insects are insectivores, those that feed on other insects. Many insects, such as grasshoppers, can potentially reproduce so quickly that they could literally bury the earth in a single season. However, there are hundreds of other insect species that feed on grasshopper eggs, and some that feed on grasshopper adults. This role in ecology is usually assumed to be primarily one of birds, but insects, though less glamorous, are much more significant. For any pest insect one can name, there is a species of wasp that is either a parasitoid or predator upon that pest, and plays a significant role in controlling it.

Human attempts to control pests by insecticides can backfire, because important but unrecognized insects already helping to control pest populations are also killed by the poison, leading eventually to population explosions of the pest species.
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Taxonomy

Subclass: Apterygota

Orders

* Archaeognatha (bristletails)
* Thysanura (silverfish)
* Monura - extinct

Subclass: Pterygota

* Infraclass: "Paleoptera" (may be paraphyletic)

Orders

* Ephemeroptera (mayflies)
* Palaeodictyoptera - extinct
* Megasecoptera - extinct
* Archodonata - extinct
* Diaphanopterodea - extinct
* Protodonata - extinct
* Odonata (dragonflies and damselflies)

* Infraclass: Neoptera

* Superorder: Exopterygota

Orders

* Caloneurodea - extinct
* Titanoptera - extinct
* Protorthoptera - extinct

Polyneoptera

* Grylloblattodea (ice-crawlers)
* Mantophasmatodea (gladiators)
* Plecoptera (stoneflies)
* Embioptera (webspinners)
* Zoraptera (angel insects)
* Dermaptera (earwigs)

Orthopteroidea

* Orthoptera (grasshoppers, etc)
* Phasmatodea (stick insects)

Dictyoptera

* Blattodea (cockroaches)
* Isoptera (termites)
* Mantodea (mantids)

Paraneoptera

* Psocoptera (booklice, barklice)
* Thysanoptera (thrips)
* Phthiraptera (lice)
* Hemiptera (true bugs)

* Superorder: Endopterygota

Orders

* Hymenoptera (ants, bees, etc.)
* Coleoptera (beetles)
* Strepsiptera (twisted-winged parasites)

Neuropteroidea

* Raphidioptera (snakeflies)
* Megaloptera (alderflies, etc.)
* Neuroptera (net-veined insects)

Mecopteroidea

* Mecoptera (scorpionflies, etc.)
* Siphonaptera (fleas)
* Diptera (true flies)
* Protodiptera extinct

Amphiesmenoptera

* Trichoptera (caddisflies)
* Lepidoptera (butterflies, moths)

Incertae sedis

* Glosselytrodea extinct
* Miomoptera - extinct

As seen above, insects are divided into two subclasses; Apterygota and Pterygota (flying insects), but this could relatively soon change. Apterygota is made up of two orders; Archaeognatha (bristletails) and Thysanura (silverfish). In the suggested classification, the Archaeognatha makes up the Monocondylia while Thysanura and Pterygota are grouped together as Dicondylia. It is even possible that the Thysanura itself are not monophyletic, making the family Lepidotrichidae a sister group to the Dicondylia (Pterygota + the rest of the Thysanura).

Also within the infraclass Neoptera we will probably see some re-organization in not too long. Today Neoptera is divided into the superorders Exopterygota and Endopterygota. But even if the Endopterygota are monophyletic, the Exopterygota seems to be paraphyletic, and can be separated into smaller groups; Paraneoptera, Dictyoptera, Orthopteroidea and to other groups (Grylloblattodea + Mantophasmatodea and Plecoptera + Zoraptera + Dermaptera). Phasmatodea and Embioptera has been suggested to form Eukinolabia, while Strepsiptera and Diptera are sometimes grouped together in Halteria. Paraneoptera has turned out to be more closeley related to Endopterygota than to the rest of the Exopterygota. It is not still clear how closley related the remaining Exopterygote groups are and if they belongs together in a larger unit. Only more research will give the answer.
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Evolution
Evolution has produced astonishing variety in insects. Pictured are some of the possible shapes of antennae.
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Evolution has produced astonishing variety in insects. Pictured are some of the possible shapes of antennae.

Main article: Insect evolution

The relationships of insects to other animal groups remain unclear. Although more traditionally grouped with millipedes and centipedes, evidence has emerged favoring closer evolutionary ties with the crustaceans. In the Pancrustacea theory insects, together with Remipedia and Malacostraca, make up a natural clade.

Apart from some tantalizing Devonian fragments, insects first appear suddenly in the fossil record at the very beginning of the Late Carboniferous period, Early Bashkirian age, about 350 million years ago. Insect species were already diverse and highly specialized by this time, with fossil evidence reflecting the presence

 

[Robert D]

Jeez Ray, couldn't you just tell him your dick's bigger than his and say he wears a pocket protector?

 

[BigRay]

Jeez Ray, couldn't you just tell him your dick's bigger than his and say he wears a pocket protector?

walters isnt intelligent. you are. mongoloids require different methods!

 

[walters]

Bigray your lower than the trash outside through the ground

 

[Robert D]

Well, that pretty much trumps any insult I've ever heard, I think......

 

[fraserhutch]

Yeah, I'm sure that put Ray in his place....

You know, pretty soon Dragon's gonna have to start charging Ray for storage

Well, that pretty much trumps any insult I've ever heard, I think......

 

[walters]

I read the manual i didn't see anything it saying it can take the LOOPS and do these kinda of LOOP rountings and LOOP configurations

different routings names and configurations

outine:
1.) Stereo
2.) Stereo (wet only)
3.) mono (wet only)
4.) Mono input/ stereo output
5.) Cascade
6.) Dual Mono
7.) Dual Stereo (parallel)
8.) Mono Split
9.) Behringer has like 6 more parallel ones
and 4 more series ones with no names

 

[SouthSIDE Glen]

Wally, if you can coherently explain what the hell is the point of this thread and why you started it to begin with in 25 words or less, I'll leave you alone on this one.

G.