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Thursday, December 17

Thursday, December 10

  1. page Toby Mac Interview (deleted) edited
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Thursday, December 3

  1. page the cold things at the top and bottom of the earth (deleted) edited
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  2. tag_del the cold things at the top and bottom of the earth untagged glacier
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  3. page The Slow Decline of the VHS Tapes edited The Decline of VHS Tapes: ... and sales, DVDhas DVD has completely taken VHS Aspects: VHS…

    The Decline of VHS Tapes:
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    and sales, DVDhasDVD has completely taken
    VHS Aspects:
    VHS tapes have approximately 3 MHz of video bandwidth, which is achieved at a relatively low tape speed by the use of helical scan recording of a frequency modulated luminance (black and white) signal, with a down-converted "color under" chroma (color) signal recorded directly at the baseband. Because VHS is an analog system, VHS tapes represent video as a continuous stream of waves, in a manner similar to analog TV broadcasts. The waveform per scan-line can reach about 160 waves at max, and contains 525 scanlines from top of the screen to bottom of the screen in NTSC (480 visible). PAL variants have 625 scanlines (576 visible). In modern-day digital terminology, VHS is roughly equivalent to 333x480 pixels.In 1987 JVC introduced the new format called Super VHS which extended the bandwidth to over 5 megahertz, yielding 420 analog horizontal (560 pixels left-to-right). They are also nearly indestructible.
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    Archived tapes (mostly VHS) at a TV Station in {http://customerservicevoodoo.files.wordpress.com/2009/08/vhs.jpg} Olympia, Washington.
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    VHS-Blu-ray player.
    Optical disc-based technologies
    The Rise of the DVD
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  4. page The Great Barrier Reef edited ... Coral Size: Individual polyps range from 3 - 56 mm in diameter or height; while colony size va…
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    Coral Size: Individual polyps range from 3 - 56 mm in diameter or height; while colony size varies from 75 mm -1500 mm (1.5 m) in width, height or length.
    Some corals have a mutualistic relationship with algae called zooxanthellae. A mutualistic relationship is one where both parties benefit from their partnership. The algae use sunlight and the polyp’s waste products to make oxygen and food. These substances leak into the surrounding tissues of the polyp and can provide up to 98% of the polyp’s dietary requirements. These corals are found in shallow water, as they require sunlight to survive. They are generally fawn, brown or green in colour, due to the yellow-brown colour of the zooxanthellae.
    Stinging cells: All Cnidarians have characteristic stinging cells called nematocysts in the tentacles and body wall. Each nematocyst cell contains a coiled thread under pressure, which is ejected from the cell when triggered by touch. These stinging cells are used for catching prey and for defense, some having barbed ends connected to poison sacs, while others are sticky.
    Summary:
    Coral polyps: Coral reefs consist of hundreds and thousands of soft-bodied, invertebrate animals, having no backbone. These animals are called coral polyps. The individual polyp is radially symmetrical and has a tubular body with tentacles surrounding the mouth at the upper end. Each polyp’s body wall consists of two layers of cells, an outer layer called the ectoderm and an inner endoderm layer. A gelatinous material called mesogloea is found in between these two layers.

    Endangered Great Barrier Reef Overview
    The Great Barrier Reef is the world's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching {http://upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Map_of_Great_Barrier_Reef_Demis.png/535px-Map_of_Great_Barrier_Reef_Demis.png} File:Map of Great Barrier Reef Demis.pngfor over 2,600 kilometres (1,600 mi) over an area of approximately 344,400 square kilometres (133,000 sq mi). The reef is located in the Coral Sea, off the coast of Queensland in northeast Australia. The Great Barrier Reef can be seen from outer space and is the world's biggest single structure made by living organisms. This reef structure is composed of and built by billions of tiny organisms, known as coral polyps. The Great Barrier Reef supports a wide diversity of life, and was selected as a World Heritage Site in 1981. CNN has labelled it one of the 7 natural wonders of the world.
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  5. page The Slow Decline of the VHS Tapes edited The Decline of VHS Tapes: ... transitioned to digital-video digital video recording. But ..…

    The Decline of VHS Tapes:
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    transitioned to digital-videodigital video recording. But
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    in them. they are
    At
    At most electronics
    VHS Aspects:
    VHS tapes have approximately 3 MHz of video bandwidth, which is achieved at a relatively low tape speed by the use of helical scan recording of a frequency modulated luminance (black and white) signal, with a down-converted "color under" chroma (color) signal recorded directly at the baseband. Because VHS is an analog system, VHS tapes represent video as a continuous stream of waves, in a manner similar to analog TV broadcasts. The waveform per scan-line can reach about 160 waves at max, and contains 525 scanlines from top of the screen to bottom of the screen in NTSC (480 visible). PAL variants have 625 scanlines (576 visible). In modern-day digital terminology, VHS is roughly equivalent to 333x480 pixels.In 1987 JVC introduced the new format called Super VHS which extended the bandwidth to over 5 megahertz, yielding 420 analog horizontal (560 pixels left-to-right). They are also nearly indestructible.
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  6. page The Great Barrier Reef edited Reef FactsThe world's first coral reefs occurred about 500 million years ago, and the first close…

    Reef FactsThe world's first coral reefs occurred about 500 million years ago, and the first close relatives of modern corals developed in southern Europe about 230 million years ago. By comparison, the Great Barrier Reef is relatively young at just 500,000 years old. The current reef's structure is much younger at less than around 8,000 years old. Most modern reefs have formed on hard surfaces in the ocean, such as a base of an old reef that died during a period when sea level was lower, or the edge of a rocky island. Depending on how they start out, several types of reefs can form. Some coral reefs form in the deep ocean and are called atolls. The theories on how coral reefs form were first put forward by Charles Darwin (of The Origin of Species fame) who proposed that atolls form around the edges of high volcanic islands that gradually submerge beneath the sea with changes in sea level or subsidence of the land. Thus an atoll starts life as a fringing reef, then becomes more of a ring growing on the shrinking land-mass, until the land disappears and just the coral circle remains. In some cases, the coral growth is unable to keep pace with the sinking island, and sunken dead reefs have been found.
    Habitat:{http://scienceguy288.files.wordpress.com/2008/02/barrier.jpg} Habitat: Coral reefs
    Living in colonies: They generally occur in large numbers as colonies of individual polyps linked by tissue. Resources, such as food, are then shared amongst the individuals in the colony.
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    or length.
    Some corals have a mutualistic relationship with algae called zooxanthellae. A mutualistic relationship is one where both parties benefit from their partnership. The algae use sunlight and the polyp’s waste products to make oxygen and food. These substances leak into the surrounding tissues of the polyp and can provide up to 98% of the polyp’s dietary requirements. These corals are found in shallow water, as they require sunlight to survive. They are generally fawn, brown or green in colour, due to the yellow-brown colour of the zooxanthellae.
    Stinging cells: All Cnidarians have characteristic stinging cells called nematocysts in the tentacles and body wall. Each nematocyst cell contains a coiled thread under pressure, which is ejected from the cell when triggered by touch. These stinging cells are used for catching prey and for defense, some having barbed ends connected to poison sacs, while others are sticky.
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  7. page Glaciers edited {180px-Perito_Moreno_Glacier_Patagonia_Argentina_Luca_Galuzzi_2005.jpg} 180px-Perito_Moreno_Glacie…
    {180px-Perito_Moreno_Glacier_Patagonia_Argentina_Luca_Galuzzi_2005.jpg} 180px-Perito_Moreno_Glacier_Patagonia_Argentina_Luca_Galuzzi_2005.jpg.
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    glacies meaning ice.[1]ice. The corresponding
    Glacier ice is the largest reservoir of fresh water on Earth, and is second only to oceans as the largest reservoir of total water. Glaciers cover vast areas of the polar regions and are found in mountain ranges of every continent except Australia. In the tropics glaciers are restricted to the highest mountains. The processes and landforms caused by glaciers and related to them are referred to as glacial. The process of glacier growth and establishment is called glaciation. Glaciers are indicators of climate and are important to world water resources and sea level variation. They are an important component of the more encompassing cryosphere.
    Types of glaciers
    Main article: Glacier morphology {http://upload.wikimedia.org/wikipedia/commons/thumb/3/34/Glacier_mouth.jpg/180px-Glacier_mouth.jpg}{http://upload.wikimedia.org/wikipedia/commons/thumb/3/34/Glacier_mouth.jpg/180px-Glacier_mouth.jpg} external image 180px-Glacier_mouth.jpg MouthMain article: Glacier morphologyMouth of the
    Glaciers are categorized in many ways including by their morphology, thermal characteristics, or their behavior. Two common types of glaciers are Alpine glaciers, which originate in mountains, and Continental ice sheets, which cover larger areas.
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    the Juneau Icefield.[2]Icefield. Ice caps
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    meters (210 ft).[3]ft). Ice shelves
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    an ice sheet.[5].sheet. They can
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    of magnitude less.[6]less. In Antarctica,
    Tidewater glaciers are glaciers that terminate in the sea. As the ice reaches the sea pieces break off, or calve, forming icebergs. Most tidewater glaciers calve above sea level, which often results in a tremendous splash as the iceberg strikes the water. If the water is deep, glaciers can calve underwater, causing the iceberg to suddenly explode up out of the water. The Hubbard Glacier is the longest tidewater glacier in Alaska and has a calving face over ten kilometers long. Yakutat Bay and Glacier Bay are both popular with cruise ship passengers because of the huge glaciers descending hundreds of feet to the water. This glacier type undergoes centuries-long cycles of advance and retreat that are much less affected by the climate changes currently causing the retreat of most other glaciers. Most tidewater glaciers are outlet glaciers of ice caps and ice fields.
    In terms of thermal characteristics, a temperate glacier is at melting point throughout the year, from its surface to its base. The ice of a polar glacier is always below freezing point from the surface to its base, although the surface snowpack may experience seasonal melting. A sub-polar glacier has both temperate and polar ice, depending on the depth beneath the surface and position along the length of the glacier.
    [edit] FormationFormation
    {http://upload.wikimedia.org/wikipedia/commons/thumb/9/93/ByrdGlacier_HiLoContrast.jpg/180px-ByrdGlacier_HiLoContrast.jpg} external image 180px-ByrdGlacier_HiLoContrast.jpg Low and high contrast images of the Byrd Glacier. The low-contrast version is similar to the level of detail the naked eye would see — smooth and almost featureless. The bottom image uses enhanced contrast to highlight flow lines on the ice sheet and bottom crevasses. Formation of glacial ice
    Glaciers form where the accumulation of snow and ice exceeds ablation. As the snow and ice thicken, they reach a point where they begin to move, due to a combination of the surface slope and the pressure of the overlying snow and ice. On steeper slopes this can occur with as little as 50 feet of snow-ice. The snow which forms temperate glaciers is subject to repeated freezing and thawing, which changes it into a form of granular ice called firn. Under the pressure of the layers of ice and snow above it, this granular ice fuses into denser and denser firn. Over a period of years, layers of firn undergo further compaction and become glacial ice. Glacier ice has a slightly reduced density from ice formed from the direct freezing of water. The air between snowflakes becomes trapped and creates air bubbles between the ice crystals.
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    the water molecule.[7]
    [edit] Anatomy
    molecule.
    Anatomy

    {http://upload.wikimedia.org/wikipedia/commons/thumb/1/12/Glacier.swiss.500pix.jpg/180px-Glacier.swiss.500pix.jpg} external image 180px-Glacier.swiss.500pix.jpg The Upper Grindelwald Glacier and the Schreckhorn, in the Swiss Alps, showing accumulation and ablation zones
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    and melt conditions.[8]conditions. The ablation
    The "health" of a glacier is usually assessed by determining the glacier mass balance or observing terminus behavior. Healthy glaciers have large accumulation zones, more than 60% of their area snowcovered at the end of the melt season, and a terminus with vigorous flow.
    Following the Little Ice Age, around 1850, the glaciers of the Earth have retreated substantially through the 1940s (see Retreat of glaciers since 1850). A slight cooling led to the advance of many alpine glaciers from 1950-
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