open-index/open-wikipedia-markdown huggingface dataset:
Time server

A **time server** is a special computer in a computer network. 

It is important that computers on a network use the same time. Time servers use an atomic clock, or they ask other computers on the network about the time. They then tell this time to all the other computers in the same network. Common protocols to do this are the Daytime Protocol and the Network Time Protocol (NTP).

NTP calls the quality of a time server its stratum.  Stratum can be anything form 0 to 255 and lower is better. It is rare to see a network with a source worse than stratum 5.
*Stratum 0 time sources are the actual clocks that track the time, usually an atomic clock or GPS receiver.
*Stratum 1 time sources are what most people mean when they talk about a time server.  They get their timing information from a master clock and send it out to the network.
*Stratum 2 time sources are computers that get their clock information from a stratum 1 time server.  They use NTP to talk to each other as well as their stratum 1 servers so they can have the best time information possible.

Every level that is added of time servers getting information from a source close to the master clock and passing it farther away from the master clock increases the stratum level.
Pneumatics

**Pneumatics** is the use of compressed air for mechanical motion.  It has many uses. 

Pneumatic transfer systems are employed in many industries to move powders and devices. Pneumatic devices are also used where electric motors cannot be used for safety reasons, such as deep in a mine where explosive dust or gases may be present.

## Examples of pneumatic tools 
* Pneumatic drill (jackhammer) used by road workers
* Pneumatic nailgun
* Pneumatic switches
* Pneumatic actuators
* Air compressors
* Vacuum pumps
* Barostat systems used in Neurogastroenterology and for researching
electricity
* Cable Jetting - a way to install cables in ducts
* Pneumatic mail systems
* Air brakes on buses, trains, and trucks

## Comparison to Hydraulics
Both pneumatics and hydraulics are applications of fluid power. Pneumatics uses air, which is compressible, while hydraulics uses relatively incompressible liquid media such as oil or water.  

### Advantages of pneumatics 
* The working fluid is very light in weight so supply hoses are not heavy.

* Because the working fluid is (mostly) just air, there is usually no need for a return line for the working fluid and leaks of the working fluid tend not to be messy.

* Because air is compressible, the equipment is less likely to be damaged by shock.  The air in pneumatics absorbs excessive force, whereas the fluid of hydraulics directly transfers force.

### Advantages of hydraulics 
* Higher energy density owing to the much higher working pressures usually employed.

* The hydraulic working fluid is basically incompressible, leading to a minimum of spring action. When hydraulic fluid flow is stopped, the slightest motion of the load releases the pressure on the load; there is no need to "bleed off" pressurised air to release the pressure on the load...

## References
## Other websites 
* www.pneumatics.be  - didactic website - for students - how pneumatics works
* U.S. Department of Energy  - Improving Compressed Air System Performance
* Fluid Power Educational Foundation  - Advancing and Supporting Hydraulic & Pneumatic Education
* Pneumatics Glossary  - Glossary of Pneumatic Terms
Specific gravity

**Specific Gravity** (SG) is a special case of relative density.

It is defined as the ratio of the density of a given substance, to the density of water (H2O). Substances with a specific gravity greater than 1 are heavier than water, and those with a specific gravity of less than 1 are lighter than water.

\mbox{SG} = \frac{\rho_\mathrm{substance}}{\rho_\mathrm{H2O} }

SG is by definition dimensionless and therefore not dependent on the system of units used (e.g. slugsft−3 or kgm−3), assuming that the units are consistent. Based on the SG-value of a given substance, the density of that substance can be calculated.

## Related pages
* Buoyancy
* Fluid mechanics
* Relative density

## Other websites
* Specific Gravity Calculator 

## References
* *Fundamentals of Fluid Mechanics* Wiley, B.R. Munson, D.F. Young & T.H. Okishi
* *Introduction to Fluid Mechanics* Fourth Edition, Wiley, SI Version, R.W. Fox & A.T. McDonald
* *Thermodynamics: An Engineering Approach* Second Edition, McGraw-Hill, International Edition, Y.A. Cengel & M.A. Boles
Mafic

**Mafic** is an adjective describing a silicate mineral or igneous rock which is rich in magnesium and iron. The term is a portmanteau, made up from "magnesium" and "ferric". 

Mafic minerals are usually dark in color and have a specific gravity greater than 3. Common rock-forming mafic minerals include olivine, pyroxene, amphibole, biotite and other micas, augite and the calcium-rich plagioclase feldspars. Common mafic rocks include basalt and gabbro.

In terms of chemistry, mafic rocks are on the other side of the rock spectrum from the so-called felsic rocks. The term roughly corresponds to the older *basic* rock class.

Mafic lava, before cooling, has a lower viscosity than felsic lava due to its lower silica content. Water and other volatiles can more easily and gradually escape from mafic lava, so eruptions of volcanoes made of mafic lavas are less explosively violent than felsic lava eruptions. Most mafic lava volcanoes are oceanic volcanoes, like Hawaii.

## Related pages
*List of minerals
*Granite
Visitor

A **visitor** is someone who does not permanently live in a place. When someone says "I am a visitor here", that means that they do not live in that place all the time. In English and Welsh law, it also means a person who can look at the working of a church, charity or university.

## Related pages
* Tourism
* Hospitality
Espresso

**Espresso** is a type of Italian coffee that is concentrated. In order to make espresso, coffee beans are powdered and hot water is added under high pressure. This is done using an espresso machine or a macchinetta. Usually, espresso is made using 1 part coffee beans to 2 parts water. This gives espresso a very strong flavor. Because espresso is so strong, it is often mixed with milk or water.

## Drinks that use espresso 
There are many drinks that use espresso, such as latte, cappuccino, caffe mocha and caffe macchiato.

## Alternative spelling 
It is sometimes spelled expresso, with an X. There is some debate as to whether this is an acceptable spelling.

## Related pages
* Coffee
Half-time

**Half-time** is the name of a break in the middle of a sports game. This break gives players a chance to rest. It also gives watchers of the game time to stretch, eat, or go to the bathroom without missing the game. During half-time, there is usually a show on the field of play. It may include a marching band or something like it. This is called a half-time show. There is a half-time show in the Super Bowl. Half time is usually 15 minutes, but in the Super Bowl it is usually about 30 minutes to give time for advertisements and performances. In Football, teams usually switch sides at the beginning of the next half. This also applies to Basketball.

## Sports with half-time 
*American football 
*Field hockey
*Lacrosse
*Football (soccer)
*Rugby football
*Basketball
*Netball
Fluid statics

''.]]

**Fluid statics** (also called **hydrostatics**) is the science of fluids at rest, and is a sub-field within fluid mechanics. The term usually refers to the mathematical treatment of the subject. It embraces the study of the conditions under which fluids are at rest in stable equilibrium. The use of fluid to do work is called hydraulics, and the science of fluids in motion is fluid dynamics. Hydrostatic pressure is pressure that a fluid exerts when pushing against the sides of a vessel.

## Related pages
* Fluid dynamics
* Fluid mechanics
* Hydraulics
Fluid mechanics

]]

**Fluid mechanics** is the study of how fluids move and the forces on them. (Fluids include liquids and gases.)

Fluid mechanics can be divided into fluid statics, the study of fluids at rest, and fluid dynamics, the study of fluids in motion. It is a branch of continuum mechanics, a subject which models matter without using the information that it is made out of atoms.

The study of fluid mechanics goes back at least to the days of ancient Greece, when Archimedes made a beginning on fluid statics. However, fluid mechanics, especially fluid dynamics, is an active field of research with many unsolved or partly solved problems. Fluid mechanics can be mathematically complex. Sometimes it can best be solved by numerical analysis, typically using computers. A modern discipline, called *Computational Fluid Dynamics* (CFD), is devoted to this approach to solving fluid mechanics problems.

## Relationship to continuum mechanics 
Fluid mechanics is a subdiscipline of continuum mechanics, as illustrated in the following table.

## Related pages
* Applied mechanics
*Hydraulics

## References
## Further reading 
* White, Frank M. (2003). *Fluid Mechanics.* McGraw-Hill. 
* Cramer, Mark. "The Gallery of Fluid Mechanics"

## Other websites 
* CFDWiki—the Computational Fluid Dynamics reference wiki.
Curtain

A **curtain** is a piece of cloth used to block light, water, or cold air from entering a place (some curtains are better at blocking than others because of the type of fabric used). Curtains are hung around showers to keep water off the floor around the shower.  Curtains are also hung around windows to keep light from coming in. A curtain is raised and lowered during a play or other theatrical production. Curtains can come in many different colors and different types of fabric. It is also originally a French word.

Curtains can also be made from air.
## References
Rosetta Stone

, London]]
]]

The **Rosetta Stone** is a stone with writing carved into it. There are 3 types of writing on the Rosetta stone; Greek, Egyptian, and another form of Egyptian writing. French soldiers found it in Egypt in 1799. It helped people get a better understanding of the Ancient Egyptian writing system called hieroglyphics. Its discovery led to the translation of Ancient Egyptian writing. The stone is named after the city where it was found, Rosetta (also called Rashid). The stone is now in the British Museum in London.

It had three pieces of writing on it that said the same thing in two different languages. Two pieces of writing were written in Ancient Egyptian, but in two different scripts: Demotic and hieroglyphics. The third writing was written in Ancient Greek.

The historians could already read the Greek. Using this knowledge they were able to work out how to read the Egyptian scripts.

The complete Greek text, in English, is about 1600–1700  words in length. The text is a royal decree from the Hellenistic period about the taxes of temple priests. It gives them back the tax  they had earlier. Some scholars believe that several copies of the Rosetta Stone might exist, as this proclamation must have been made at many temples.

## The discovery of the stone 
The soldiers who discovered the stone were part of Napoleon Bonaparte's 1798 campaign in Egypt. It was given to the British as part of the surrender arrangements when French forces were caught in Alexandria by the Battle of the Nile and a larger force of British and Ottoman troops. The surrender and treaty is called the Capitulation of Alexandria. Under the treaty, the French had to hand over their archaeological discoveries to the British, and that included the Rosetta Stone.

The discovered part of the stone is 114.4 centimeters (45&nbsp;in) high at its tallest point, 72.3 centimeters (28.5&nbsp;in) wide, and 27.9 centimeters (11&nbsp;in) thick.

## Part of the text 
These are some of the translated words on the stone:

## References 
## Other websites 
* A Rosetta Stone website
* Rosetta Stone -Citizendium
Microphone

U87 capacitor microphone.]]
A **microphone**, sometimes referred to as a **mike** or **mic** (both IPA pronunciation: ), converts sound into an electrical signal.

Microphones are used in many applications such as telephones, tape recorders, hearing aids, motion picture production, live and recorded audio engineering, in radio and television broadcasting and in computers for recording voice.

## Kinds of Microphones 
Sound passes through the air in waves, and as was said above, the microphone turns the sound wave into an electrical wave.  Different kinds of microphones will turn the sound waves into electricity in different ways.

* **Carbon button** — This is the first kind to become commonplace, being used in most 20th century telephones. Sound waves, by compressing and decompressing a piece of carbon, change the amount of electric current flowing in the wire, thus creating electrical waves. This kind became rarer late in the century, due in part to lack of high fidelity. 
* **Dynamic** — This uses a round plastic or rubber disk connected to a wire coil in order to turn sound into electricity.  The sound wave hits the disk which vibrates as a result.  This vibration moves the coil back and forth near a magnet very quickly in order to create an electrical current.  The dynamic microphone is the exact opposite of a speaker which uses an electrical current to move the coil, which moves the disk.  Then the disk makes sound.
** **Ribbon** — This is similar to a Dynamic microphone.  A thin, small sheet of metal (tin or aluminum usually) hangs between two magnets.  When sound hits the thin piece of metal, the metal vibrates.  That vibration creates an electrical signal in the metal.
* **Condenser** — This uses two small metal plates to create an electrical current.  Basically, two small metal plates are placed very near to each other and electricity is run through the plates.  This creates an electric field between the two plates.  When sound hits these plates, the plates vibrate.  The vibration makes small changes in the electric field.  These changes create the electrical signal.
* Crystal or ceramic microphones use piezoelectricity.

## Equipment 
A pop filter (or pop shield) is often used in recording studios.  It is an electronic filter that reduces or eliminates 'popping' sounds caused by fast moving air (such as air from the mouth).

## History
The first microphones were invented as telephone transmitters. They included liquid and dynamic designs. Carbon transmitters were later used in this and other applications.

## Related pages
* Loudspeaker — The inverse of a dynamic microphone

## Other websites
* Info, Pictures and Soundbytes from vintage microphones
* Microphone construction and basic placement advice 
* History of the Microphone 
* Microphone sensitivity conversion — dB re 1 V/Pa and transfer factor mV/Pa
* Large vs. Small Diaphragms in Omnidirectional Microphones 

## References
Meroë

. There are many pyramids there. Most of them are in ruins. The city tells of the glory of past kings, which are buried in the pyramids.]]

**Meroë** (Meroitic: *Medewi* or *Bedewi*) is the name of an ancient city. What remains of the city is on the east bank of the Nile  about 6 km north-east of the Kabushiya station near Shendi, Sudan. It lies about 200 km north-east of Khartoum.
There are a few villages nearby. They are called  **Bagrawiyah**.

Meroë was the capital of the Kingdom of Kush for several centuries. The Kushitic Kingdom of Meroë gave its name to the "Island of Meroë", which was the modern region of Butana, a region bounded by the Nile (from the Atbarah River to Khartoum), the Atbarah, Ethiopia, and the Blue Nile.  The city of Meroë was on the edge of Butana and there were two other Meroitic cities in Butana, Musawwarat es-Sufra and Naqa.  

The site of the city of Meroë is marked by over two hundred pyramids in three groups. Of many of these pyramids, there are only ruins left.

In June 2011, the archaeological site of Meroë was listed by UNESCO as World Heritage Sites.

## References
Laxative

A **laxative** is a food or drug taken to make bowel movements easier, or to treat constipation. Sometimes taking powerful or lots of laxatives can cause diarrhea or a flatulence.  

Laxatives work by helping your intestines digest undigested food, and do not make you lose weight. Despite this, some people with eating disorders take laxatives in an attempt to lose weight.

## References
Dassault Mirage III

i Mirage]]
The **Mirage III** is a fighter aircraft made by French airplane company Dassault Aviation. If first flew in 1956 and was introduced in 1961. It used a triangle wing (called a delta wing). It had 2 cannons and some missiles. Because it was an interceptor, an airplane made to shoot down enemy airplanes at high speed, it could go Mach 2.2. It was used by Israel in the Six-Day War.
Nakalipithecus

***Nakalipithecus nakayamai*** is a fossil ape species. It was a discovery of a 10-million-year-old jawbone with teeth, in a volcanic mud in Nakali, Kenya. *N. nakayamai* is thought to have lived around 9.9 million to 9.8 million years ago. More teeth were found in the same place; eleven of them are thought to belong to this specimen. 

## Other websites 
*New ancient ape species discovered
*Jawbone sheds light on divergence of humans and apes
Defoliant

spraying Agent Orange, a defoliant, during the Vietnam War.]]
, about 1973]]
**Defoliants** are a type of chemical that destroys plants like trees, bushes and grass .

A very common defoliant is Agent Orange used by the US Airforce in the Vietnam War to destroy cover of the enemy. It killed the rainforest and caused birth defects as well as other illnesses among Vietnamese and US soldiers

## References
909

## Events 
* The Maya leave their biggest towns and cities.

## Births 
* Saint Dunstan, Archbishop of Canterbury

## References
Trophy

tournament in Benin]]
A **trophy** is an object given to someone because of an accomplishment. These are often given out through sporting events.  

A trophy can be in the shape of a cup, a bowl, a plaque, a mug (these usually painted or engraved with something), a human shape (like the Emmy Award), or a spaceship (like the Hugo Award for science-fiction).  

Trophies can also be an animal head. These are often taken as trophies by hunters.

## History
In ancient times people would take heads or other body parts of enemies they had killed in a battle to show how good a warrior they were.
Many years ago (in Ancient Greece and Ancient Rome) the winners did not get any trophy, only a wreath (a wreath is made of flowers and looks like a crown). The winner also got olive oil in a container that was similar to today trophies. In local games, the winners got different trophies, such as a vase or a silver cup.
In ancient Rome, the tradition of getting a trophy was slowly forgotten and money were given instead.
Trophies were introduced back in the world on large scale in last century. Football, rugby and baseball trophies were introduced.
Today trophies are mostly made from plastic and are easily accessible to public thanks to low prices.

## References
Bilateria

The **Bilateria** are animals which are bilaterally symmetrical. They have front and a back end, an upside and downside, and a left and right side. Most animals are bilateral.

## Main subgroups 
* Deuterostomia
** Echinodermata (20,000 species, 7000 living) 
** Chordata. mostly Vertebrata  (63,000 species)
** Hemichordata
* Protostomia
** Ecdysozoa (6 to 20 million species) 
***Nematoda (20,000 species known +many more)
***Arthropoda (one to 10 million species)
** Lophotrochozoa 
***Annelida (17,000 species)
***Platyhelminthes (20,000+ species)
***Mollusca (85,000+ species)
***Brachiopoda (5,000 fossil species)
***Rhombozoa
** Platyzoa
** Minor phyla (like Chaetognatha)
Numbers are approximate; extinct species numbers cannot be known for most phyla.

## Related pages 
*List of animal phyla

## References
Lyre

, the centaur from Greek mythology, teaching the young Achilles to play the lyre.]]
A **lyre** (pronounced to rhyme with "fire") is a musical instrument which is like a mixture between a harp and a guitar. It is held in one hand and the strings are strummed using the other hand. The lyre is classified as a plucked string instrument and a member of the lute family. 

Lyres were among the first string instruments to be invented. People played them in various ancient cultures (including the Sumerian, Egyptian, and Greek) to accompany music, poetry, and dance. The lyre's origins can be traced back over 4,500 years to the ancient Middle East, with notable examples found in the Sumerian culture of Babylonia.

Lyres are typically plucked, though some are bowed, and they come in different forms, such as box lyres and bowl lyres, with varying numbers of strings and materials.  A lyre has two arms and a crossbar, with strings stretched between the crossbar and a tailpiece or soundbox. 

Lyres are crafted from various materials, including wood, animal shells, and metal. The strings are plucked to produce sound, creating a peaceful, relaxing, and beautiful tone.
Saxe-Eisenach

**Saxe-Eisenach** () was the name of three different Ernestine duchies that existed at different times in Thuringia. The chief town and capital of all three duchies was Eisenach.

## History
The first Duchy of Saxe-Eisenach was created in 1596 for Johann Ernst, younger son of Johann Frederick II of Saxe-Coburg-Eisenach.

In 1633, the Wettin line died out, and Johann Ernst inherited it, but he died heirless in 1638, and the territories of Saxe-Gotha and Saxe-Eisenach were split between Saxe-Weimar and Saxe-Altenburg.

In 1640 Saxe-Eisenach was again separated off from Saxe-Weimar for Albert, son of John II of Saxe-Weimar, but after just four years he too died without an heir, and Saxe-Eisenach was then divided between Saxe-Gotha and Saxe-Weimar, ruled by his brothers Ernst and Wilhelm.

In 1662 Wilhelm, Duke of Saxe-Weimar died, leaving four children: Johann Ernst, Adolf Wilhelm, Johann Georg and Bernhard. Adolf Wilhelm, got Eisenach, but he had to share this with his younger brother Johann Georg. Johann Georg eventually took an allowance from the duchy instead of taking part in the government, and moved to live in the small town of Marksuhl. Adolf William’s first four sons died soon after birth. In 1668 he died, just before of the birth of his fifth child, Wilhelm August, who became the new Duke of Saxe-Eisenach from his birth, with Johann Georg as regent. A sickly boy, he died in 1671 at only two years old, and Johann Georg I became the duke of Saxe-Eisenach.

Saxe-Eisenach changed again in 1672. Frederick William III of Saxe-Altenburg died and his lands were split. The line of Johann Georg I ruled Saxe-Eisenach for 69 years, until Duke Wilhelm Heinrich died heirless in 1741. Ernst August I of Saxe-Weimar, Wilhelm's second cousin, inherited Saxe-Eisenach; he and his successors ruled Saxe-Weimar and Saxe-Eisenach in a personal union until 1809, when the duchies were formally merged into the Duchy of Saxe-Weimar-Eisenach.

## Dukes of Saxe-Eisenach 
### First creation 
Created in 1572 as Saxe-Coburg-Eisenach
1596 divided into Saxe-Coburg and Saxe-Eisenach
* Johann Casimir (1572 – 1633, ruled Saxe-Coburg)
* Johann Ernst (1572 – 1638, retained Saxe-Eisenach)
Divided between Saxe-Altenburg and Saxe-Weimar

### Second creation 
* Albrecht (1640 – 44)
Divided between Saxe-Gotha and Saxe-Weimar

### Third creation 
* Adolf Wilhelm (1662 – 68)
* Wilhelm August (1668 – 71)
* Johann Georg I (1671 – 86)
* Johann Georg II (1686 – 98)
* Johann Wilhelm (1698 – 1729)
* Wilhelm Heinrich (1729 – 41)
Line extinct

### Personal union with Saxe-Weimar 
* Ernst August I (1741-1748)
* Ernst August II (1748-1758)
* Karl August (1758-1809)
Merged with Saxe Weimar into Saxe-Weimar-Eisenach

## Related pages
* Ernestine duchies

## Other websites
* German genealogies
Oceanic crust

The **oceanic crust** is the part of Earth's lithosphere that is under the ocean basins.

Oceanic crust is primarily composed of mafic rocks, or sima which is named for its magnesium silicate minerals. It is thinner than continental crust, and is about 7-10 kilometers thick, however it is more dense, having a mean density of about 3.3 g/cm3.

Oceanic crust generally does not last longer than 200 million years. In the rock cycle, it is continuously created at oceanic ridges. At these ridges, hot magma rises into the crust and cools, pushing the crust apart at the ridge. The continuous formation of new oceanic crust pushes the older crust away from the mid-ocean ridge. As it moves away from the ridge, the crust becomes cooler and denser, while the sediment may build on top of it.

## Related pages
*Continental crust

## References
## Sources
*Marshak, Stephen. (2005) Earth: Portrait of a Planet (41-87)

## Other websites 
*Testing the Sea-Floor Spreading Hypothesis
Continental crust

The **continental crust** is the layer of granitic, sedimentary, and metamorphic rocks which form the continents and the areas of shallow seabed close to their shores, known as continental shelves.

It consists mostly of feldspar and other sialic rocks. It is less dense than the material of the Earth's mantle, which consists of mafic rock. Continental crust is also less dense than oceanic crust, though it is considerably thicker; mostly 35 to 40&nbsp;km versus the average oceanic thickness of around 7–10&nbsp;km. About 40% of the Earth's surface lies on-top of continental crust.

The continental crust is separated from the oceanic crust by the continental margin.

## Related pages 
* Oceanic crust

## References 
* Butler, Rob, Making new continents  Accessed 01/29/2006
* Saal, A.L., Rudnick R.L., Ravizza G.E. & Hart S.R., 1998. *Re-Os isotope evdence for the composition, formation and age of the lower crust.* Nature, 39317, 1998.
* Taylor and McLennan, 1995, *Model of growth of continental crust through time* in John Victor Walther, 2005, *Essentials Of Geochemistry*, Jones & Bartlett, 
* von Huene, R. and D.W. Scholl, 1991. "Observations at convergent margins concerning sediment subduction, subduction erosion, and the growth of continental crust." Reviews of Geophysics, 29, 279-316.

## Other websites
*Average composition of Continental Crust
*Crust 5.1
Eumetazoa

**Eumetazoa** is a clade which includes all major animal phyla except sponges, and a few other groups of animals, such as the Placozoa. The Eumetazoa have true tissues, neurons, and an embryo that goes through a gastrula stage. 

## Subgroups 
* Radiata
* Bilateria

## References 
* Borchiellini C. *et al.*  2001.  *Journal of Evolutionary Biology* **14** (1): 171-179.
* Peterson, Kevin J. *et al.* 2005. Tempo & mode of early animal evolution: inferences from rocks, Hox, & molecular clocks.  *Paleobiology* **31**(2, Supplement): 36-55.
Herbaceous plant

A **herbaceous plant** is a plant that does not have much wood and its stems are green and soft. These plants grow fast and produce flowers and many seeds in a short period of time.

In botany, the word for a herbaceous plant is **herb** (from Latin *herba*, "grass") but it is common to use the word herb only for plants that are used in perfumes, medicines and for cooking, even if they are not herbaceous plants.

Herbaceous plants may be annuals, biennials or perennials. Most are annuals and die at the end of their growing season (the time when they produce flowers, fruits and seeds), leaving their seeds on the soil. Those seeds will produce new plants with good weather. Wheat and pea are annual herbaceous plants.

Biennial and perennial herbaceous plants will live for two or more years, but the stems that are in the air will die every year. The underground stems will form the new aerial stems (stems that are above the ground). Underground roots and stems can better resist bad weather (winter or a very dry season) than leaves and stems that are above the ground. Bulbs are biennial and peonies are perennial herbaceous plants.

Most herbaceous plants are small and their stems are not thick because they do not have much wood, but there are some big herbaceous plants. Bananas and papaya (a tropical fruit) are herbaceous plants but they look like trees. Papaya has a thick stem but without much wood.

Herbaceous plants are the first plants with flower that come to live in barren lands (lands without plant life), because they are small and produce many seeds. They are also found in places where the weather conditions are not good for most plants. They can use the little rain that falls in deserts. They can get enough heat to grow where the soil is covered with snow and ice most of the year, like in very high mountains.

## References
Shift work

**Shift work** is a working practice which is designed to use all 24 hours of a day, and not only the standard working day hours.

A day for example can be divided into three eight-hour shifts. An  only works one of the shifts in each day. The "first shift" is in the morning, the "second shift" is in the afternoon and evening and the "third shift" is overnight.

The "second shift", also known as the *swing shift* in some places, is the work shift which takes place in the afternoon and evening. It usually extends from 4 PM (16:00) to midnight, or from 3 PM (15:00) to 11 PM (23:00).

The "third shift", the *night shift*, is usually from 11 PM (23:00) or 12-midnight (00:00) to 07:00 or 08:00 in the morning.

## Health effects 
The World Health Organization (WHO) claimed in December 2007 that shift work might cause cancer but currently there is no evidence to support the claim

A study by Knutsson *et al.* in 1986 showed that labors who work shift work in a production floor (papermill as per the research) for more than 15 years, are 3 times more likely to develop ischaemic heart diseases.

## References
Grumman F6F Hellcat

The **F6F Hellcat** was a United States Navy fighter aircraft made by Grumman during World War II. It first flew in 1942 and was introduced in 1943.  It was supposed to be a little bit better than the F4F Wildcat, but became a big improvement.  It was more powerful and could turn better.  It was made to fight the Japanese A6M Zero. It was able to take off of aircraft carriers.  It was also used by the navy as a "night fighter", with radar so it could fly at night. During the war, it had the most aces fly it.  It was retired in 1954.

The Hellcat was a rival to the Vought F4U Corsair and had more aerial victories and participated in more missions.  The F6F was equipped with Browning Machine Guns, and had external fuel tanks for longer range.  It had the same engine as the F4U.  The armor of the Hellcat was better than that on other aircraft.

## References
**Notes**
Grumman F4F Wildcat

The **F4F Wildcat** was a fighter aircraft made by Grumman. It first flew in 1937, and was introduced in 1940. It was used in the Pacific during the early years of World War II. It could take off from aircraft carriers. During the war, it mainly fought the A6M Zero. Because the Wildcat was not beating the Zero, a new airplane was made called the F6F Hellcat. The Wildcat continued to fight in places where the Hellcat was too big, and was retired in 1945.

## References
Mitsubishi A6M Zero

The **Mitsubishi A6M Zero**, often called just the **A6M Zero** or simply the **Zero** was a long range carrier ship-based fighter aircraft of the Imperial Japanese Navy during World War II. The aircraft was built by Mitsubishi, making its first flight in 1939, and entering naval service in 1940.

The Mitsubishi A6M Zero was an amazing performing and nimble aircraft from the **Japanese**, most widely remembered for its performance in the **Pacific War**. The Mitsubishi A6M Zero (also known as ‘The Zero’) was a **versatile fighter** aircraft, usually used as ambush aircraft, **bomber attackers** and sometimes escorts. People would often rate the A6M a ‘Zero’ out of 10. 

It was the primary fighter used by Japan during the war. It was the primary enemy of US Naval aircraft such as the Grumman F4F Wildcat, Vought F4U Corsair, and later the Grumman F6F Hellcat, which was specifically designed to combat the Zero. The A6M Zero was the best fighter at the beginning of the Pacific war. However, late in the war, new American fighters were able to defeat it.

## Related pages 
* F4F Wildcat
* F6F Hellcat

## References
## Other websites
Étang Saumâtre

**Étang Saumâtre** (in English, *brackish pond*) is the largest lake of Haiti. It is the second largest lake of Hispaniola, after Lake Enriquillo. It is also known as **Lake Azuei**. It is known as *Lago del Fondo* in the Dominican Republic. Its Taíno name was *Yainagua*.

The lake is on the arid part of the Plain of the Cul-de-Sac. It is  east of Port-au-Prince in the Ouest Department. Its eastern side is part of the border between Haiti and the Dominican Republic; the Dominican city of Jimaní is at less than 1&nbsp;km from the southeast end of the lake.

The salt-water lake has a length, from northwest to southeast, of . Its maximum width is . The total area is . Because it is an arid region, the vegetation around the lake is poor with cacti and small shrubs.

## References
CONCACAF Champions Cup

The **CONCACAF Champions Cup** (formerly called the **CONCACAF Champions League**) is a football competition between the best club teams in North and Central America and the Caribbean. The teams are selected by the Central American and Caribbean Association of Football (the CONCACAF) because of their good performances in matches.

## Records and statistics (all time) 
### Winners 
### Top-ten countries
Dennis Rader

**Dennis Lynn Rader** (born March 9, 1945 ) is an American serial killer. He murdered 10 people near Wichita, Kansas between 1974 and 1991.  He was known as the **BTK killer** (or the **BTK strangler**).  *BTK* stands for Bind, Torture, Kill.  He was named this because that was what he did to the people he killed. Letters were written soon after the killings and sent to police and to local news outlets. They talked about the crimes. The letters had information which only the killer and police knew about the crimes. The letters stopped being sent for a long time. In 2004, they started being sent again. This led to him being located in 2005 and found guilty of the murders. Rader was sentenced to at least 175 years imprisonment.

## References
Saxe-Coburg

**Saxe-Coburg** () was a country in today's Bavaria, Germany. It was part of the Duchy of Saxe-Coburg-Eisenach after the Division of Erfurt in 1572. In 1596 Saxe-Coburg-Eisenach was split, Johann Casimir got Saxe-Coburg and Johann Ernst got Saxe-Eisenach. When Casimir died in 1633, his brother Ernst of Saxe-Eisenach both countries until he died in 1638. Saxe-Coburg was then given to other Ernestine duchies.

It became again a duchy in 1681. From 1699, when Albrecht of Saxe-Coburg died without sons until 1735 it shared a ruler with the Duke of Saxe-Saalfeld. In 1735 the two duchies were merged as Saxe-Coburg-Saalfeld.

## Related pages
* Ernestine duchies

## References 
* Saxe-Coburg and Gotha Royal Family
Saxe-Coburg-Eisenach

**Saxe-Coburg-Eisenach** was one of the short lived Ernestine duchies.  It only existed between 1572 - 1596 and again from 1633 - 1638.  It was a part of the Holy Roman Empire, today it is within the federal states of Bavaria and Thuringia.

## Creation 
The duchy was created by the Division of Erfurt in 1572 when Coburg and Eisenach were split from the Duchy of Saxony-Weimar for Johann Casimir and Johann Ernst, the sons of Johann Friedrich II, the Middle.

## Rulers 
The two princes at this time were still children, so the Elector August of Saxony was regent until 1586.  This is when Johann Casimir and Johann Ernst becgan to rule the duchy.  Johann Ernst retired to his hunting lodge in Marksühl, and in 1590 the two brothers divided the country. Johann Casimir  kept Saxe-Coburg, and Johann Ernst took Saxe-Eisenach. Johann Casimir died in 1633so his brother Johann Ernst inherited his possessions, again were short and Coburg and Eisenach were reunited until Johann Ernst's death in 1638.

### Division 
Johann Ernst also had no children, so the Saxe-Coburg-Eisenach line died out, out the territory was divided between the other Ernestine line.
Deuterostome

**Deuterostomes** are a nephrozoan superphylum of bilaterian animals, a taxon above the level of phylum. It is not part of the usual system of classification.

They are bilateral animals, and are contrasted with the protostomes. Deuterostomes are distingued by their embryo: in deuterostomes, the first opening (the blastopore) becomes the anus, while in protostomes it becomes the mouth.

## Classification 
These are the living phyla of deuterostomes:
*Chordata (vertebrates and their kin)
*Echinodermata (starfishes, sea urchins, sea cucumbers, etc.)
*Hemichordata (acorn worms and possibly graptolites)
This is an extinct deuterostome clade:
*Saccorhytida
Value-added tax

**Value-added tax** (often called by its initial letters "VAT" or “V.A.T.”) is the English name of a tax that is called **goods and services tax** in some places. It is like a sales tax that is charged in some US States.  In the UK it is charged at 20%.

The tax is paid every time goods are sold.
* The maker charges the wholesaler VAT and pays the tax to the government
* The wholesaler charges the shop VAT and pays the government the tax minus the tax it has already paid to the maker
* The shop charges the customer VAT and pays the government the tax minus the tax it has already paid to the wholesaler.

The tax can be complicated to work out, because every business or person has to charge the tax, and have an  to show they have paid it. The only person who pays the full amount of tax is the customer.

The government also charges VAT on some services. This is because some companies do not make a thing which can be used (goods) instead they do something to help a customer (that is, provide a service).

For example, a garage-owner might sell a spare part for a customer’s car. The garage-owner charges VAT because spare parts are “goods”. If the garage-owner helps the customer by fitting the spare parts into the car, the garage-owner would charge extra for his time, and would also charge VAT on the amount he charged for the service of fitting the parts.

VAT is not added to all products. In the United Kingdom, children's books and clothes do not have VAT. Staple foods are not taxed - but luxury foods are. A famous legal case about Jaffa Cakes in 1991 was about the difference.  There was a later case about flapjacks.  Hot takeaway food is taxed but cold takeaway food isnt.

## References
Norman Mailer

**Norman Kingsley Mailer** (January 31, 1923 – November 10, 2007) was an American writer and journalist. He was born in Long Branch, New Jersey and raised in Brooklyn, New York City.

Along with Truman Capote, Joan Didion, and Tom Wolfe, Mailer writes creative nonfiction, sometimes called New Journalism, but which covers the essay to the nonfiction novel. He was awarded the Pulitzer Prize twice and the National Book Award once on his journalism career. In 1955, Mailer, along with Ed Fancher and Dan Wolf, first published *The Village Voice*, which was shown to the Greenwich Village. In 2005, he won the Medal for Distinguished Contribution to American Letters from The National Book Foundation.

Mailer died of renal failure in New York City.

## Other websites
* The Norman Mailer Society 
* Norman Mailer at Books and Writers 
* Norman Mailer on American Masters (PBS Broadcast)
* Norman Mailer's writing on the Huffington Post
* Norman Mailer New York Review of Books author profile and archive includes list of reviews, letters, and essays from over 40 years, along with a bibliography
Hannelore Kohl

**Johanna Klara Eleonore "Hannelore" Kohl** (née **Renner**; 7 March 1933 – 5 July 2001) was the wife of former German Chancellor Helmut Kohl (died 2017). She met him for the first time in Ludwigshafen, Germany, when she was 15 years old.

She was born in Berlin as **Eleonore Johanna Renner**, and later, she changed her first name to "Hannelore". When her husband was chancellor she set up the Hannelore Kohl *Stiftung* (that is the Hannelore Kohl Charity) and the Kuratorium ZNS, a foundation to help find a cure for illnesses of the central nervous system.

In 1945, when she was 12, she was raped by Red Army soldiers.

On 5 July 2001, Mrs Kohl was found dead in her home in Ludwigshafen. She had apparently committed suicide with an overdose of sleeping pills. She was said to have suffered from photo allergy (sunlight burns the skin).

However, journalist Andrew Gimson, writing in *The Spectator* questioned official version of events, and so did the German newsmagazine, *Stern* and the BBC.

Kohl is known for her collection of German-style cooking recipes, *Kulinarische Reise durch Deutsche Länder* (*Culinary Journey through German Regions*), published in 1996.

## References
## Other websites
* Hannelore Kohl's Gravesite
List of cities in the United Kingdom

This is a **list of cities in the United Kingdom** . It lists places that have been given city status by letters patent or royal charter.  

## List of cities 
## Notes 
## References
Walter Scheel

**Walter Scheel** (8 July 1919 &ndash; 24 August 2016) was a German politician (FDP).

## Biography 
Scheel was born in Solingen.
During World War II, he became a member of the Nazi Party and served in the Luftwaffe, the last years of the war as a Radar operator on a Me 110 night fighter.

He was federal minister of economic cooperation and development (1961–1966), but he persuaded the FDP to leave Ludwig Erhard's coalition government in late 1966. This forced elections in Germany, and Kurt Georg Kiesinger became chancellor.

In 1969 his party formed a new coalition with the Social Democrats. He became Foreign Minister and Vice Chancellor. With Willy Brandt his foreign policy meant the Federal Republic of Germany promised not to try and get back the parts of Germany given to Poland and the USSR. The treaty with Poland actually defined the western border of Poland, not the border between Poland and Germany. It is the same thing, but meant Poland could sign a treaty with West Germany that described the border of East Germany.

When Brandt resigned on 7 May 1974, Scheel, was acting chancellor, for about a week, until Helmut Schmidt was elected Chancellor.
]]
A few weeks later, Scheel was elected Federal President of West Germany, a post he held from July 1974 until June 1979.

Like most ex German presidents, Scheel retired from political life term ended. He sometimes appeared on political talk shows or events. At the funeral of the murdered businessman Hanns Martin Schleyer in October 1977, Scheel gave a speech entitled *shame*.

## Death
Scheel died on 24 August 2016 following a long illness. Having lived to  he holds the record as the longest-lived German head of state, either imperial or elected.

## References
Pineal gland

The **pineal gland** is a small endocrine gland in the middle of the brain of humans and other vertebrates. It makes and releases the hormone named **melatonin**.

There is almost no melatonin in the blood in the daytime. At the end of the day, melatonin in the blood allows sleepiness in humans and other animals which sleep at night. There is melatonin in the blood all night, while the person or animal is sleeping. In the morning, there is less and less melatonin in the blood. When light enters the eyes, the melatonin of the blood goes away.

Some people have circadian rhythm sleep disorders which make them sleepy much earlier or much later than normal. The most common one is Delayed Sleep-Phase Disorder (DSPD, or Delayed Sleep-Phase Syndrome, DSPS). People with DSPD usually go to bed at 3 in the morning or later but they sleep normally for at least eight hours.

## References 
* Eakin R.M 1973. *The third eye*. Berkeley: University of California Press.
* Guyton A.C. & Hall J.E. 2001. *Textbook of medical physiology*. 10th ed, Saunders.
Gamma-hydroxybutyric acid

**γ-Hydroxybutyric acid** (**gamma-hydroxybutyric acid**, commonly shortened to **GHB**)  is a chemical substance. Small quantities of it can be found in the central nervous system of many animals. 

In the central nervous system, GHB interacts with other neurotransmitters, such as gamma-Aminobutyric acid (GABA). 

Many countries have regulated it as an illegal drug, even though it can be used in medicine. It can be used as an anesthetic, and a sedative. In the past it has been used to treat insomnia and depression. It can also help people who have a problem with alcoholism or cataplexy. In patients with narcolepsy it has been used to treat sleepiness during the day. Athletes have used it to make their performance better.

The drug has been used as a recreational drug. This is because it can make a person euphoric. Many countries have made it illegal if it is not used as medicine. Its most common name as an illegal drug is probably **liquid Ecstasy**. However, ecstasy is a different drug that is unrelated to GHB. It has also been used as a date rape drug. 

GHB is naturally produced in the human body's cells. Its chemical structure is similar to that of ketone body beta-hydroxybutyrate. As a supplement or drug, it is used most as a salt. GHB is also produced as a result of fermentation. Small amounts of the substance can be found in some beers and wines. 

GHB can cause 'GHB comas'. This is when people faint or become unconscious. This is what causes most deaths.

## Use as an illegal drug
GHB is a depressant of the central nervous system. Its effects have been described as similar to those of alcohol or ecstasy. People feel in a good mood. They also lower their inhibitions. If the dose is increased, the symptoms include nausea, drowsiness, breathing problems, amnesia, unconsciousness and death. The effects of GHB last between 1.5 and 3 hours, but may be longer. The effects when alcohol is used together with GHB, can last longer than 3 hours.

Certain substances called "pro-drugs", are changed to GHB in the stomach. One such drug, is gamma-butyrolactone. Such products are also a problem. Lots of them are used in industrial processes. An example of this are paint strippers. What is fine for use in industry may be bad for humans.

Some street names, especially when mixed with other substances such as amphetamines, can be Soap, Water, Salty water, Blue water, and Grievous Bodily Harm.

## Related pages 
* Dopamine
* Acetylcholine

## References
Reichsmark

The **Reichsmark** (which was shown with the symbol **RM**) was the currency in Germany from 1924 until June 20, 1948. One Reichsmark was subdivided into 100 *Reichspfennig*.

## Banknotes images 

file:20 Reichsmark 1924 Deutsche Reichsbank.png|20 RM, 1924
file:50 Reichspfennig 1938-1945.png|50 Rpf, 1938–1945
file:1 Reichsmark 1938-1945.png|1 RM, 1938–1945
file:2 Reichsmark 1938-1945.png|2 RM, 1938–1945
file:5 Reichsmark 1938-1945.png|5 RM, 1938–1945
file:20 Reichsmark 1938-1945.png|20 RM, 1938–1945
file:50 Reichsmark 1938-1945.png|50 RM, 1938–1945

## Other websites 
* Coins of the Third Reich
Plum (color)

s on a plum tree]]

**Plum** is a color similar to purple. The name comes from the fruit called a plum.

The first written use of *plum* as a color name in English was in 1805.

## Meaning of plum
* In business, the color plum represents a business deal that is profitable—a *plum* contract. A *plum* job is a job that one is assigned to that has a high salary or the job may be a sinecure with good pay but not much work to do. Thus, the color plum represents prosperity.

## Tones of plum color comparison chart
## Related pages
* List of colors

## References