sentence-transformers/squad huggingface dataset:
Passage: Under contract from the U.S. Military, Matrox produced a combination computer/LaserDisc player for instructional purposes. The computer was a 286, the LaserDisc player only capable of reading the analog audio tracks. Together they weighed 43 lb (20 kg) and sturdy handles were provided in case two people were required to lift the unit. The computer controlled the player via a 25-pin serial port at the back of the player and a ribbon cable connected to a proprietary port on the motherboard. Many of these were sold as surplus by the military during the 1990s, often without the controller software. Nevertheless, it is possible to control the unit by removing the ribbon cable and connecting a serial cable directly from the computer's serial port to the port on the LaserDisc player.

Question: A combination computer/LD player was comissioned by what government entity?

Question: How much did Matrox's computer/LD combo weigh?

Question: How could Matrox's computer unconventionally be controlled?
Passage: The format's instant-access capability made it possible for a new breed of LaserDisc-based video arcade games and several companies saw potential in using LaserDiscs for video games in the 1980s and 1990s, beginning in 1983 with Sega's Astron Belt. American Laser Games and Cinematronics produced elaborate arcade consoles that used the random-access features to create interactive movies such as Dragon's Lair and Space Ace. Similarly, the Pioneer Laseractive and Halcyon were introduced as home video game consoles that used LaserDisc media for their software.

Question: What quality made LDs a consideration for videogames in the 1980s and 1990s?

Question: What was the first game to use LaserDiscs?

Question: In what year was Sega's AStron Belt released?
Passage: In 1991, several manufacturers announced specifications for what would become known as MUSE LaserDisc, representing a span of almost 15 years until the feats of this HD analog optical disc system would finally be duplicated digitally by HD DVD and Blu-ray Disc. Encoded using NHK's MUSE "Hi-Vision" analogue TV system, MUSE discs would operate like standard LaserDiscs but would contain high-definition 1,125-line (1,035 visible lines) (Sony HDVS) video with a 5:3 aspect ratio. The MUSE players were also capable of playing standard NTSC format discs and are superior in performance to non-MUSE players even with these NTSC discs. The MUSE-capable players had several noteworthy advantages over standard LaserDisc players, including a red laser with a much narrower wavelength than the lasers found in standard players. The red laser was capable of reading through disc defects such as scratches and even mild disc rot that would cause most other players to stop, stutter or drop-out. Crosstalk was not an issue with MUSE discs, and the narrow wavelength of the laser allowed for the virtual elimination of crosstalk with normal discs.

Question: With what operating ratio would MUSE Discs operate?

Question: What benefits did the MUSE narrow wavelength red laser have?

Question: In addition to scratches and rot, what other common LaserDisc issue was to be eliminated by MUSE discs?

Question: How many years did it take Blu-ray and HD-DVD players to duplicate MUSE technology?
Passage: In order to view MUSE encoded discs, it was necessary to have a MUSE decoder in addition to a compatible player. There are televisions with MUSE decoding built-in and set top tuners with decoders that can provide the proper MUSE input. Equipment prices were high, especially for early HDTVs which generally eclipsed US$10,000, and even in Japan the market for MUSE was tiny. Players and discs were never officially sold in North America, although several distributors imported MUSE discs along with other import titles. Terminator 2: Judgment Day, Lawrence of Arabia, A League of Their Own, Bugsy, Close Encounters of the Third Kind, Bram Stoker's Dracula and Chaplin were among the theatrical releases available on MUSE LDs. Several documentaries, including one about Formula One at Japan's Suzuka Circuit were also released.

Question: What was the price for early HDTVs?

Question: Did MUSE have a large or small target market, even in Japan?

Question: What were some movies that were released on MUSE LaserDiscs?
Passage: With the release of 16:9 televisions in the mid-1990s, Pioneer and Toshiba decided that it was time to take advantage of this aspect ratio. Squeeze LDs were enhanced 16:9-ratio widescreen LaserDiscs. During the video transfer stage, the movie was stored in an anamorphic "squeezed" format. The widescreen movie image was stretched to fill the entire video frame with less or none of the video resolution wasted to create letterbox bars. The advantage was a 33% greater vertical resolution compared to letterboxed widescreen LaserDisc. This same procedure was used for anamorphic DVDs, but unlike all DVD players, very few LD players had the ability to unsqueeze the image for 4:3 sets, and very few if any 4:3 sets could be set to play them properly either. If the discs were played on a standard 4:3 television the image would be distorted. Since very few people owned 16:9 displays, the marketability of these special discs was very limited.

Question: What were "Squeeze LDs"?

Question: With what aspect ratio did Squeeze LDs operate?

Question: Why did Squeeze LDs have a very limited market?

Question: Could the 16:9 aspect ratio be easily resized by a normal LD player, or was the image significantly distorted?

Question: What percent vertical resolution increase did Squeeze LDs feature over regular widescreen LDs?
Passage: There were no anamorphic LaserDisc titles available in the US except for promotional purposes. Upon purchase of a Toshiba 16:9 television viewers had the option of selecting a number of Warner Bros. 16:9 films. Titles include Unforgiven, Grumpy Old Men, The Fugitive, and Free Willy. The Japanese lineup of titles was different. A series of releases under the banner "SQUEEZE LD" from Pioneer of mostly Carolco titles included Basic Instinct, Stargate, Terminator 2: Judgment Day, Showgirls, Cutthroat Island, and Cliffhanger. Terminator 2 was released twice in Squeeze LD, the second release being THX certified and a notable improvement over the first.

Question: Which movie was released twice on Squeeze LD?

Question: What improvement was added to Terminator 2's second Squeeze LD release?

Question: What Warner Brothers films were available in 16:9 aspect ratio Squeeze LDs?

Question: What films were available for Japanese market Squeeze LDs?
Passage: Another form of recordable LaserDisc that is completely playback-compatible with the LaserDisc format (unlike CRVdisc with its caddy enclosure) is the RLV, or Recordable LaserVision disc. It was developed and first marketed by the Optical Disc Corporation (ODC, now ODC Nimbus) in 1984. RLV discs, like CRVdisc, are also a WORM technology, and function exactly like a CD-R disc. RLV discs look almost exactly like standard LaserDiscs, and can play in any standard LaserDisc player after they have been recorded.

Question: What does the acronym RLV stand for?

Question: Which company originally developed and marketed the RLV?

Question: In what year did ODC develop the Recordable LaserVision Disc?
Passage: The only cosmetic difference between an RLV disc and a regular factory-pressed LaserDiscs is their reflective purple-violet (or blue with some RLV discs) color resulting from the dye embedded in the reflective layer of the disc to make it recordable, as opposed to the silver mirror appearance of regular LDs. The purplish color of RLVs is very similar to DVD-R and DVD+R discs. RLVs were popular for making short-run quantities of LaserDiscs for specialized applications such as interactive kiosks and flight simulators.

Question: What is the difference in appearance between an RLV disc and a regular LD?

Question: Why do RLV discs have a blue or purple reflective color?

Question: For what purpose were RLVs popular?

Question: What color were regular LaserDiscs, in contrast to RLVs blueish purple hues?
Passage: There were also 12 cm (4.7 in) (CD size) "single"-style discs produced that were playable on LaserDisc players. These were referred to as CD Video (CD-V) discs, and Video Single Discs (VSD). A CD-V carried up to five minutes of analog LaserDisc-type video content (usually a music video), as well as up to 20 minutes of digital audio CD tracks. The original 1989 release of David Bowie's retrospective Sound + Vision CD box set prominently featured a CD-V video of Ashes to Ashes, and standalone promo CD-Vs featured the video, plus three audio tracks: "John, I'm Only Dancing", "Changes", and "The Supermen".

Question: In contrast to large LD disks, what is the size of a standard CD?

Question: What were CD size "single"-style discs called that were compatible with LaserDisc players?

Question: How much video content could be stored on a CD-V disk?

Question: What were CD-V's video capacities usually used for?

Question: Which artist released a music video and three audio tracks on CD-V in 1989?
Passage: CD-Vs are not to be confused with Video CDs (which are all-digital and can only be played on VCD players, DVD players, CD-i players, computers, and later-model LaserDisc players, such as the DVL series from Pioneer that can also play DVDs). CD-Vs can only be played back on LaserDisc players with CD-V capability. VSDs were the same as CD-Vs, but without the audio CD tracks. CD-Vs were somewhat popular for a brief time worldwide, but soon faded from view. VSDs were popular only in Japan and other parts of Asia, and were never fully introduced to the rest of the world.

Question: What were VSDs lacking that CD-Vs included?

Question: In what areas of the world were VSDs popular?

Question: Were VSDs or CD-Vs all digital and also playable on DVD players?
Passage: The annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion. Most textbooks still use the traditional division into polychaetes (almost all marine), oligochaetes (which include earthworms) and leech-like species. Cladistic research since 1997 has radically changed this scheme, viewing leeches as a sub-group of oligochaetes and oligochaetes as a sub-group of polychaetes. In addition, the Pogonophora, Echiura and Sipuncula, previously regarded as separate phyla, are now regarded as sub-groups of polychaetes. Annelids are considered members of the Lophotrochozoa, a "super-phylum" of protostomes that also includes molluscs, brachiopods, flatworms and nemerteans.

Question: What kind of symmetry do annelids have?

Question: What do annelids use to move?

Question: Which subtype of annelids includes most marine worms?

Question: Which subtype of annelids includes earthworms?

Question: Since 1997, what are leeches seen as a subgroup of?
Passage: The basic annelid form consists of multiple segments. Each segment has the same sets of organs and, in most polychaetes, has a pair of parapodia that many species use for locomotion. Septa separate the segments of many species, but are poorly defined or absent in others, and Echiura and Sipuncula show no obvious signs of segmentation. In species with well-developed septa, the blood circulates entirely within blood vessels, and the vessels in segments near the front ends of these species are often built up with muscles that act as hearts. The septa of such species also enable them to change the shapes of individual segments, which facilitates movement by peristalsis ("ripples" that pass along the body) or by undulations that improve the effectiveness of the parapodia. In species with incomplete septa or none, the blood circulates through the main body cavity without any kind of pump, and there is a wide range of locomotory techniques – some burrowing species turn their pharynges inside out to drag themselves through the sediment.

Question: What separates many annelids' segments?

Question: Which annelids show no segmentation?

Question: What end of annelids with well-developed segmentation has muscles that act like hearts?

Question: What is movement by ripples called?

Question: What movement method do some burrowing annelids use?
Passage: Although many species can reproduce asexually and use similar mechanisms to regenerate after severe injuries, sexual reproduction is the normal method in species whose reproduction has been studied. The minority of living polychaetes whose reproduction and lifecycles are known produce trochophore larvae, that live as plankton and then sink and metamorphose into miniature adults. Oligochaetes are full hermaphrodites and produce a ring-like cocoon around their bodies, in which the eggs and hatchlings are nourished until they are ready to emerge.

Question: How do annelids normally reproduce?

Question: What can asexual reproduction techniques help annelids do?

Question: What larvae live like plankton?

Question: What annelids are hermaphrodites?

Question: What annelids make a cocoon in a ring around themselves?
Passage: Earthworms are Oligochaetes that support terrestrial food chains both as prey and in some regions are important in aeration and enriching of soil. The burrowing of marine polychaetes, which may constitute up to a third of all species in near-shore environments, encourages the development of ecosystems by enabling water and oxygen to penetrate the sea floor. In addition to improving soil fertility, annelids serve humans as food and as bait. Scientists observe annelids to monitor the quality of marine and fresh water. Although blood-letting is no longer in favor with doctors, some leech species are regarded as endangered species because they have been over-harvested for this purpose in the last few centuries. Ragworms' jaws are now being studied by engineers as they offer an exceptional combination of lightness and strength.

Question: How do earthworms help the soil they live in?

Question: How much of near-shore marine annelids are burrowing?

Question: How do burrowing marine annelids help ocean ecosystems?

Question: What annelids' jaws are being studied by engineers?

Question: Why are some leeches endangered?
Passage: Since annelids are soft-bodied, their fossils are rare – mostly jaws and the mineralized tubes that some of the species secreted. Although some late Ediacaran fossils may represent annelids, the oldest known fossil that is identified with confidence comes from about 518 million years ago in the early Cambrian period. Fossils of most modern mobile polychaete groups appeared by the end of the Carboniferous, about 299 million years ago. Palaeontologists disagree about whether some body fossils from the mid Ordovician, about 472 to 461 million years ago, are the remains of oligochaetes, and the earliest indisputable fossils of the group appear in the Tertiary period, which began 65 million years ago.

Question: Why are annelid fossils rare?

Question: What fossil signs of annelids are found?

Question: How old is the earliest annelid fossil?

Question: What types of annelids appeared 299 million years ago?

Question: What period started around 472 million years ago?
Passage: No single feature distinguishes Annelids from other invertebrate phyla, but they have a distinctive combination of features. Their bodies are long, with segments that are divided externally by shallow ring-like constrictions called annuli and internally by septa ("partitions") at the same points, although in some species the septa are incomplete and in a few cases missing. Most of the segments contain the same sets of organs, although sharing a common gut, circulatory system and nervous system makes them inter-dependent. Their bodies are covered by a cuticle (outer covering) that does not contain cells but is secreted by cells in the skin underneath, is made of tough but flexible collagen and does not molt – on the other hand arthropods' cuticles are made of the more rigid α-chitin, and molt until the arthropods reach their full size. Most annelids have closed circulatory systems, where the blood makes its entire circuit via blood vessels.

Question: What externally divides annelids' segments?

Question: What divides annelids' segments internally?

Question: What do the segments of an annelid share?

Question: What covers an annelid's exterior?

Question: What is an annelid's cuticle made of?
Passage: Most of an annelid's body consists of segments that are practically identical, having the same sets of internal organs and external chaetae (Greek χαιτη, meaning "hair") and, in some species, appendages. However, the frontmost and rearmost sections are not regarded as true segments as they do not contain the standard sets of organs and do not develop in the same way as the true segments. The frontmost section, called the prostomium (Greek προ- meaning "in front of" and στομα meaning "mouth") contains the brain and sense organs, while the rearmost, called the pygidium (Greek πυγιδιον, meaning "little tail") or periproct contains the anus, generally on the underside. The first section behind the prostomium, called the peristomium (Greek περι- meaning "around" and στομα meaning "mouth"), is regarded by some zoologists as not a true segment, but in some polychaetes the peristomium has chetae and appendages like those of other segments.

Question: What language does the term 'chaetae' come from?

Question: What does 'chaetae' mean?

Question: Which parts of annelids are different from true segments?

Question: What language does 'prostomium' come from?

Question: What does 'pygidium' mean?
Passage: Annelids' cuticles are made of collagen fibers, usually in layers that spiral in alternating directions so that the fibers cross each other. These are secreted by the one-cell deep epidermis (outermost skin layer). A few marine annelids that live in tubes lack cuticles, but their tubes have a similar structure, and mucus-secreting glands in the epidermis protect their skins. Under the epidermis is the dermis, which is made of connective tissue, in other words a combination of cells and non-cellular materials such as collagen. Below this are two layers of muscles, which develop from the lining of the coelom (body cavity): circular muscles make a segment longer and slimmer when they contract, while under them are longitudinal muscles, usually four distinct strips, whose contractions make the segment shorter and fatter. Some annelids also have oblique internal muscles that connect the underside of the body to each side.

Question: How are the layers arranged in annelids' cuticles?

Question: What are annelids' cuticles made out of?

Question: What do non-cuticle annelids use to protect their skin?

Question: What layer is under the epidermis?

Question: What does 'coelom' mean?
Passage: The setae ("hairs") of annelids project out from the epidermis to provide traction and other capabilities. The simplest are unjointed and form paired bundles near the top and bottom of each side of each segment. The parapodia ("limbs") of annelids that have them often bear more complex chetae at their tips – for example jointed, comb-like or hooked. Chetae are made of moderately flexible β-chitin and are formed by follicles, each of which has a chetoblast ("hair-forming") cell at the bottom and muscles that can extend or retract the cheta. The chetoblasts produce chetae by forming microvilli, fine hair-like extensions that increase the area available for secreting the cheta. When the cheta is complete, the microvilli withdraw into the chetoblast, leaving parallel tunnels that run almost the full length of the cheta. Hence annelids' chetae are structurally different from the setae ("bristles") of arthropods, which are made of the more rigid α-chitin, have a single internal cavity, and are mounted on flexible joints in shallow pits in the cuticle.

Question: What are parapodia?

Question: What do chetoblast cells do?

Question: What hair-like extensions do chetoblasts make?

Question: What are setae?
Passage: Nearly all polychaetes have parapodia that function as limbs, while other major annelid groups lack them. Parapodia are unjointed paired extensions of the body wall, and their muscles are derived from the circular muscles of the body. They are often supported internally by one or more large, thick chetae. The parapodia of burrowing and tube-dwelling polychaetes are often just ridges whose tips bear hooked chetae. In active crawlers and swimmers the parapodia are often divided into large upper and lower paddles on a very short trunk, and the paddles are generally fringed with chetae and sometimes with cirri (fused bundles of cilia) and gills.

Question: What are cirri?

Question: What kind of parapodia do burrowing annelids often have?

Question: What type of annelids have limb-like parapodia?

Question: What are parapodia?
Passage: The brain generally forms a ring round the pharynx (throat), consisting of a pair of ganglia (local control centers) above and in front of the pharynx, linked by nerve cords either side of the pharynx to another pair of ganglia just below and behind it. The brains of polychaetes are generally in the prostomium, while those of clitellates are in the peristomium or sometimes the first segment behind the peristomium. In some very mobile and active polychaetes the brain is enlarged and more complex, with visible hindbrain, midbrain and forebrain sections. The rest of the central nervous system is generally "ladder-like", consisting of a pair of nerve cords that run through the bottom part of the body and have in each segment paired ganglia linked by a transverse connection. From each segmental ganglion a branching system of local nerves runs into the body wall and then encircles the body. However, in most polychaetes the two main nerve cords are fused, and in the tube-dwelling genus Owenia the single nerve chord has no ganglia and is located in the epidermis.

Question: What are ganglia?

Question: What is an annelid's brain in a ring around?

Question: What is a pharynx?

Question: Where are clitellates' brains?

Question: Where are polychaetes' brains?
Passage: As in arthropods, each muscle fiber (cell) is controlled by more than one neuron, and the speed and power of the fiber's contractions depends on the combined effects of all its neurons. Vertebrates have a different system, in which one neuron controls a group of muscle fibers. Most annelids' longitudinal nerve trunks include giant axons (the output signal lines of nerve cells). Their large diameter decreases their resistance, which allows them to transmit signals exceptionally fast. This enables these worms to withdraw rapidly from danger by shortening their bodies. Experiments have shown that cutting the giant axons prevents this escape response but does not affect normal movement.

Question: What species group are annelids' muscle control similar to?

Question: What are giant axons?

Question: How do annelids withdraw from danger?
Passage: The sensors are primarily single cells that detect light, chemicals, pressure waves and contact, and are present on the head, appendages (if any) and other parts of the body. Nuchal ("on the neck") organs are paired, ciliated structures found only in polychaetes, and are thought to be chemosensors. Some polychaetes also have various combinations of ocelli ("little eyes") that detect the direction from which light is coming and camera eyes or compound eyes that can probably form images. The compound eyes probably evolved independently of arthropods' eyes. Some tube-worms use ocelli widely spread over their bodies to detect the shadows of fish, so that they can quickly withdraw into their tubes. Some burrowing and tube-dwelling polychaetes have statocysts (tilt and balance sensors) that tell them which way is down. A few polychaete genera have on the undersides of their heads palps that are used both in feeding and as "feelers", and some of these also have antennae that are structurally similar but probably are used mainly as "feelers".

Question: What kind of things can annelids' sensors detect?

Question: What does 'nuchal' mean?

Question: What type of annelids have nuchal organs?

Question: What are the nuchal organs thought to do?

Question: What term means 'little eyes'?