["[Dialogue between User and Assistant on 2024-01-01 00:00]\n<User>The following are some more news I learnt:\nAnother advantage, at least to some consumers, was the lack of any sort of anti-piracy technology. It was claimed that Macrovision's Copyguard protection could not be applied to LaserDisc, due to the format's design. The vertical blanking interval, where the Macrovision signal would be implemented, was also used for the internal timing on LaserDisc players, so test discs with Macrovision would not play at all. There was never a push to redesign the format despite the obvious potential for piracy due to its relatively small market share. The industry simply decided to engineer it into the DVD specification.\n\nLaserDisc's support for multiple audio tracks allowed for vast supplemental materials to be included on-disc and made it the first available format for \"Special Edition\" releases; the 1984 Criterion Collection edition of Citizen Kane is generally credited as being the first \"Special Edition\" release to home video,[citation needed] and for setting the standard by which future SE discs were measured. The disc provided interviews, commentary tracks, documentaries, still photographs, and other features for historians and collectors.\n\nThe space-consuming analog video signal of a LaserDisc limited playback duration to 30 minutes (CAV) or 60 minutes (CLV) per side because of the hardware manufacturer's refusal to reduce line count for increased playtime. After one side was finished playing, a disc has to be flipped over in order to continue watching a movie, and some titles fill two or more discs. Many players, especially units built after the mid-1980s, can \"flip\" discs automatically by rotating the optical pickup to the other side of the disc, but this is accompanied by a pause in the movie during the side change. If the movie is longer than what could be stored on two sides of a single disc, manually swapping to a second disc is necessary at some point during the film. One exception to this rule is the Pioneer LD-W1, which features two disc platters. In addition, perfect still frames and random access to individual still frames is limited only to the more expensive CAV discs, which only had a playing time of approximately 30 minutes per side. In later years, Pioneer and other manufacturers overcame this limitation by incorporating a digital memory buffer, which \"grabbed\" a single frame from a CLV disc.\n\nThe analog information encoded on LaserDiscs does not include any form of built-in checksum or error correction. Because of this, slight dust and scratches on the disc surface can result in read-errors which cause various video quality problems: glitches, streaks, bursts of static, or momentary picture interruptions. In contrast, the digital MPEG-2 format information used on DVDs has built-in error correction which ensures that the signal from a damaged disc will remain identical to that from a perfect disc right up until the point at which damage to the disc surface is so substantial that it prevents the laser from being able to identify usable data.\n\nIn addition, LaserDisc videos sometimes exhibit a problem known as \"crosstalk\". The issue can arise when the laser optical pickup assembly within the player is out of alignment or because the disc is damaged or excessively warped, but it could also occur even with a properly functioning player and a factory-new disc, depending on electrical and mechanical alignment problems. In these instances, the issue arose due to the fact that CLV discs require subtle changes in rotating speed at various points during playback. During a change in speed, the optical pickup inside the player might read video information from a track adjacent to the intended one, causing data from the two tracks to \"cross\"; the extra video information picked up from that second track shows up as distortion in the picture which looks reminiscent of swirling \"barber poles\" or rolling lines of static.\n\nAssuming the player's optical pickup is in proper working order, crosstalk distortion normally does not occur during playback of CAV format LaserDiscs, as the rotational speed never varies. However, if the player calibration is out of order or if the CAV disc is faulty or damaged, other problems affecting tracking accuracy can occur. One such problem is \"laser lock\", where the player reads the same two fields for a given frame over and over again, causing the picture to look frozen as if the movie were paused.\n<Assistant>Sure I will remember them.", "[Dialogue between User and Assistant on 2024-01-02 00:00]\n<User>The following are some new knowledge:\nAnother significant issue unique to LaserDisc is one involving the inconsistency of playback quality between different makers and models of player. On most televisions, a given DVD player will produce a picture that is visually indistinguishable from other units. Differences in image quality between players only becomes easily apparent on large televisions and substantial leaps in image quality are generally only obtained with expensive, high-end players that allow for post-processing of the MPEG-2 stream during playback. In contrast, LaserDisc playback quality is highly dependent on hardware quality. Major variances in picture quality appear between different makers and models of LD players, even when tested on a low to mid-range television. The obvious benefits of using high quality equipment has helped keep demand for some players high, thus also keeping pricing for those units comparably high. In the 1990s, notable players sold for anywhere from US$200 to well over $1,000, while older and less desirable players could be purchased in working condition for as little as $25.\n<Assistant>Great! I've added this to my knowledge base.", "[Dialogue between User and Assistant on 2024-01-03 00:00]\n<User>The following are some new knowledge:\nMany early LDs were not manufactured properly; sometimes a substandard adhesive was used to sandwich together the two sides of the disc.[citation needed] The adhesive contained impurities that were able to penetrate the lacquer seal layer and chemically attack the metalized reflective aluminium layer, causing it to oxidize and lose its reflective characteristics. This was a problem that was termed \"laser rot\" among LD enthusiasts, also called \"color flash\" internally by LaserDisc-pressing plants. Some forms of laser rot could appear as black spots that looked like mold or burned plastic which cause the disc to skip and the movie to exhibit excessive speckling noise. But, for the most part, rotted discs could actually appear perfectly fine to the naked eye.\n\nLaserDisc did not have high market penetration in North America due to the high cost of the players and discs, which were far more expensive than VHS players and tapes, and due to marketplace confusion with the technologically inferior CED, which also went by the name Videodisc. While the format was not widely adopted by North American consumers, it was well received among videophiles due to the superior audio and video quality compared to VHS and Betamax tapes, finding a place in nearly one million American homes by the end of 1990. The format was more popular in Japan than in North America because prices were kept low to ensure adoption, resulting in minimal price differences between VHS tapes and the higher quality LaserDiscs, helping ensure that it quickly became the dominant consumer video format in Japan. Anime collectors in every country the LD format was released, which includes both North America and Japan, also quickly became familiar with this format, and sought the higher video and sound quality of LaserDisc and the availability of numerous titles not available on VHS. LaserDiscs were also popular alternatives to videocassettes among movie enthusiasts in the more affluent regions of South East Asia, such as Singapore, due to their high integration with the Japanese export market and the disc-based media's superior longevity compared to videocassette, especially in the humid conditions endemic to that area of the world.\n\nThe format also became quite popular in Hong Kong during the 1990s before the introduction of VCDs and DVD; although people rarely bought the discs (because each LD was priced around USD100), high rental activity helped the video rental business in the city grow larger than it had ever been previously. Due to integration with the Japanese export market, NTSC LaserDiscs were used in the Hong Kong market, in contrast to the PAL standard used for broadcast (This anomaly also exists for DVD). This created a market for multi-system TVs and multi-system VCRs which could display or play both PAL and NTSC materials in addition to SECAM materials (which were never popular in Hong Kong). Some LD players could convert NTSC signals to PAL so that most TVs used in Hong Kong could display the LD materials.\n\nAlthough the LaserDisc format was supplanted by DVD by the late 1990s, many LD titles are still highly coveted by movie enthusiasts (for example, Disney's Song of the South which is unavailable in the US in any format, but was issued in Japan on LD). This is largely because there are many films that are still only available on LD and many other LD releases contain supplemental material not available on subsequent DVD versions of those films. Until the end of 2001, many titles were released on VHS, LD, and DVD in Japan.\n\nIn the early 1980s, Philips produced a LaserDisc player model adapted for a computer interface, dubbed \"professional\". In 1985, Jasmine Multimedia created LaserDisc Juke Boxes featuring music videos from Michael Jackson, Duran Duran, and Cyndi Lauper. When connected to a PC this combination could be used to display images or information for educational or archival purposes, for example thousands of scanned medieval manuscripts. This strange device could be considered a very early equivalent of a CD-ROM.\n\nIn the mid-1980s Lucasfilm pioneered the EditDroid non-linear editing system for film and television based on computer-controlled LaserDisc players. Instead of printing dailies out on film, processed negatives from the day's shoot would be sent to a mastering plant to be assembled from their 10-minute camera elements into 20-minute film segments. These were then mastered onto single-sided blank LaserDiscs, just as a DVD would be burnt at home today, allowing for much easier selection and preparation of an Edit Decision List. In the days before video assist was available in cinematography, this was the only other way a film crew could see their work. The EDL went to the negative cutter who then cut the camera negative accordingly and assembled the finished film. Only 24 EditDroid systems were ever built, even though the ideas and technology are still in use today. Later EditDroid experiments borrowed from hard-drive technology of having multiple discs on the same spindle and added numerous playback heads and numerous electronics to the basic jukebox design so that any point on each of the discs would be accessible within seconds. This eliminated the need for racks and racks of industrial LaserDisc players since EditDroid discs were only single-sided.\n\nIn 1986, a SCSI-equipped LaserDisc player attached to a BBC Master computer was used for the BBC Domesday Project. The player was referred as an LV-ROM (LaserVision Read Only Memory) as the discs contained the driving software as well as the video frames. The discs used the CAV format, and encoded data as a binary signal represented by the analog audio recording. These discs could contain in each CAV frame video/audio or video/binary data, but not both. \"Data\" frames would appear blank when played as video. It was typical for each disc to start with the disc catalog (a few blank frames) then the video introduction before the rest of the data. Because the format (based on the ADFS hard disc format) used a starting sector for each file, the data layout effectively skipped over any video frames. If all 54,000 frames are used for data storage an LV-ROM disc can contain 324 MB of data per side. The Domesday Project systems also included a genlock, allowing video frames, clips and audio to be mixed with graphics originated from the BBC Master; this was used to great effect for displaying high resolution photographs and maps, which could then be zoomed into.\n\nApple's HyperCard scripting language provided Macintosh computer users with a means to design databases of slides, animation, video and sounds from LaserDiscs and then to create interfaces for users to play specific content from the disc through software called LaserStacks. User-created \"stacks\" were shared and were especially popular in education where teacher-generated stacks were used to access discs ranging from art collections to basic biological processes. Commercially available stacks were also popular with the Voyager company being possibly the most successful distributor.\n\nUnder 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.\n\nThe 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.\n\nIn 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.\n<Assistant>Understood. I'll keep these facts for future reference.", "[Dialogue between User and Assistant on 2024-01-04 00:00]\n<User>The following are some more news I learnt:\nIn 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.\n\nWith 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.\n\nThere 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.\n\nAnother 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.\n\nThe 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.\n\nThere 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\".\n\nCD-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.\n\nThe 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.\n<Assistant>I've processed this information and will remember it.", "[Dialogue between User and Assistant on 2024-01-05 00:00]\n<User>Let me update you with some new information:\nThe 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 \u2013 some burrowing species turn their pharynges inside out to drag themselves through the sediment.\n\nAlthough 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.\n\nEarthworms 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.\n\nSince annelids are soft-bodied, their fossils are rare \u2013 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.\n<Assistant>Thanks for the update. I've recorded these facts.", "[Dialogue between User and Assistant on 2024-01-06 00:00]\n<User>Here are some news I learnt earlier:\nNo 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 \u2013 on the other hand arthropods' cuticles are made of the more rigid \u03b1-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.\n\nMost of an annelid's body consists of segments that are practically identical, having the same sets of internal organs and external chaetae (Greek \u03c7\u03b1\u03b9\u03c4\u03b7, 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 \u03c0\u03c1\u03bf- meaning \"in front of\" and \u03c3\u03c4\u03bf\u03bc\u03b1 meaning \"mouth\") contains the brain and sense organs, while the rearmost, called the pygidium (Greek \u03c0\u03c5\u03b3\u03b9\u03b4\u03b9\u03bf\u03bd, meaning \"little tail\") or periproct contains the anus, generally on the underside. The first section behind the prostomium, called the peristomium (Greek \u03c0\u03b5\u03c1\u03b9- meaning \"around\" and \u03c3\u03c4\u03bf\u03bc\u03b1 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.\n\nAnnelids' 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.\n\nThe 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 \u2013 for example jointed, comb-like or hooked. Chetae are made of moderately flexible \u03b2-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 \u03b1-chitin, have a single internal cavity, and are mounted on flexible joints in shallow pits in the cuticle.\n\nNearly 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.\n\nThe 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.\n\nAs 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.\n\nThe 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\".\n\nMost annelids have a pair of coelomata (body cavities) in each segment, separated from other segments by septa and from each other by vertical mesenteries. Each septum forms a sandwich with connective tissue in the middle and mesothelium (membrane that serves as a lining) from the preceding and following segments on either side. Each mesentery is similar except that the mesothelium is the lining of each of the pair of coelomata, and the blood vessels and, in polychaetes, the main nerve cords are embedded in it. The mesothelium is made of modified epitheliomuscular cells; in other words, their bodies form part of the epithelium but their bases extend to form muscle fibers in the body wall. The mesothelium may also form radial and circular muscles on the septa, and circular muscles around the blood vessels and gut. Parts of the mesothelium, especially on the outside of the gut, may also form chloragogen cells that perform similar functions to the livers of vertebrates: producing and storing glycogen and fat; producing the oxygen-carrier hemoglobin; breaking down proteins; and turning nitrogenous waste products into ammonia and urea to be excreted.\n<Assistant>Wonderful. I'll remember these key points.", "[Dialogue between User and Assistant on 2024-01-07 00:00]\n<User>Here's some more information I came across:\nMany annelids move by peristalsis (waves of contraction and expansion that sweep along the body), or flex the body while using parapodia to crawl or swim. In these animals the septa enable the circular and longitudinal muscles to change the shape of individual segments, by making each segment a separate fluid-filled \"balloon\". However, the septa are often incomplete in annelids that are semi-sessile or that do not move by peristalsis or by movements of parapodia \u2013 for example some move by whipping movements of the body, some small marine species move by means of cilia (fine muscle-powered hairs) and some burrowers turn their pharynges (throats) inside out to penetrate the sea-floor and drag themselves into it.\n\nThe fluid in the coelomata contains coelomocyte cells that defend the animals against parasites and infections. In some species coelomocytes may also contain a respiratory pigment \u2013 red hemoglobin in some species, green chlorocruorin in others (dissolved in the plasma) \u2013 and provide oxygen transport within their segments. Respiratory pigment is also dissolved in the blood plasma. Species with well-developed septa generally also have blood vessels running all long their bodies above and below the gut, the upper one carrying blood forwards while the lower one carries it backwards. Networks of capillaries in the body wall and around the gut transfer blood between the main blood vessels and to parts of the segment that need oxygen and nutrients. Both of the major vessels, especially the upper one, can pump blood by contracting. In some annelids the forward end of the upper blood vessel is enlarged with muscles to form a heart, while in the forward ends of many earthworms some of the vessels that connect the upper and lower main vessels function as hearts. Species with poorly developed or no septa generally have no blood vessels and rely on the circulation within the coelom for delivering nutrients and oxygen.\n\nHowever, leeches and their closest relatives have a body structure that is very uniform within the group but significantly different from that of other annelids, including other members of the Clitellata. In leeches there are no septa, the connective tissue layer of the body wall is so thick that it occupies much of the body, and the two coelomata are widely separated and run the length of the body. They function as the main blood vessels, although they are side-by-side rather than upper and lower. However, they are lined with mesothelium, like the coelomata and unlike the blood vessels of other annelids. Leeches generally use suckers at their front and rear ends to move like inchworms. The anus is on the upper surface of the pygidium.\n\nFeeding structures in the mouth region vary widely, and have little correlation with the animals' diets. Many polychaetes have a muscular pharynx that can be everted (turned inside out to extend it). In these animals the foremost few segments often lack septa so that, when the muscles in these segments contract, the sharp increase in fluid pressure from all these segments everts the pharynx very quickly. Two families, the Eunicidae and Phyllodocidae, have evolved jaws, which can be used for seizing prey, biting off pieces of vegetation, or grasping dead and decaying matter. On the other hand, some predatory polychaetes have neither jaws nor eversible pharynges. Selective deposit feeders generally live in tubes on the sea-floor and use palps to find food particles in the sediment and then wipe them into their mouths. Filter feeders use \"crowns\" of palps covered in cilia that wash food particles towards their mouths. Non-selective deposit feeders ingest soil or marine sediments via mouths that are generally unspecialized. Some clitellates have sticky pads in the roofs of their mouths, and some of these can evert the pads to capture prey. Leeches often have an eversible proboscis, or a muscular pharynx with two or three teeth.\n\nThe gut is generally an almost straight tube supported by the mesenteries (vertical partitions within segments), and ends with the anus on the underside of the pygidium. However, in members of the tube-dwelling family Siboglinidae the gut is blocked by a swollen lining that houses symbiotic bacteria, which can make up 15% of the worms' total weight. The bacteria convert inorganic matter \u2013 such as hydrogen sulfide and carbon dioxide from hydrothermal vents, or methane from seeps \u2013 to organic matter that feeds themselves and their hosts, while the worms extend their palps into the gas flows to absorb the gases needed by the bacteria.\n<Assistant>Perfect. I've stored this information in my memory.", "[Dialogue between User and Assistant on 2024-01-08 00:00]\n<User>Here's some more information I came across:\nAnnelids with blood vessels use metanephridia to remove soluble waste products, while those without use protonephridia. Both of these systems use a two-stage filtration process, in which fluid and waste products are first extracted and these are filtered again to re-absorb any re-usable materials while dumping toxic and spent materials as urine. The difference is that protonephridia combine both filtration stages in the same organ, while metanephridia perform only the second filtration and rely on other mechanisms for the first \u2013 in annelids special filter cells in the walls of the blood vessels let fluids and other small molecules pass into the coelomic fluid, where it circulates to the metanephridia. In annelids the points at which fluid enters the protonephridia or metanephridia are on the forward side of a septum while the second-stage filter and the nephridiopore (exit opening in the body wall) are in the following segment. As a result, the hindmost segment (before the growth zone and pygidium) has no structure that extracts its wastes, as there is no following segment to filter and discharge them, while the first segment contains an extraction structure that passes wastes to the second, but does not contain the structures that re-filter and discharge urine.\n<Assistant>Excellent. I've documented all of this information.", "[Dialogue between User and Assistant on 2024-01-09 00:00]\n<User>I've gathered some additional data to share:\nIt is thought that annelids were originally animals with two separate sexes, which released ova and sperm into the water via their nephridia. The fertilized eggs develop into trochophore larvae, which live as plankton. Later they sink to the sea-floor and metamorphose into miniature adults: the part of the trochophore between the apical tuft and the prototroch becomes the prostomium (head); a small area round the trochophore's anus becomes the pygidium (tail-piece); a narrow band immediately in front of that becomes the growth zone that produces new segments; and the rest of the trochophore becomes the peristomium (the segment that contains the mouth).\n\nHowever, the lifecycles of most living polychaetes, which are almost all marine animals, are unknown, and only about 25% of the 300+ species whose lifecycles are known follow this pattern. About 14% use a similar external fertilization but produce yolk-rich eggs, which reduce the time the larva needs to spend among the plankton, or eggs from which miniature adults emerge rather than larvae. The rest care for the fertilized eggs until they hatch \u2013 some by producing jelly-covered masses of eggs which they tend, some by attaching the eggs to their bodies and a few species by keeping the eggs within their bodies until they hatch. These species use a variety of methods for sperm transfer; for example, in some the females collect sperm released into the water, while in others the males have a penis that inject sperm into the female. There is no guarantee that this is a representative sample of polychaetes' reproductive patterns, and it simply reflects scientists' current knowledge.\n\nSome polychaetes breed only once in their lives, while others breed almost continuously or through several breeding seasons. While most polychaetes remain of one sex all their lives, a significant percentage of species are full hermaphrodites or change sex during their lives. Most polychaetes whose reproduction has been studied lack permanent gonads, and it is uncertain how they produce ova and sperm. In a few species the rear of the body splits off and becomes a separate individual that lives just long enough to swim to a suitable environment, usually near the surface, and spawn.\n\nMost mature clitellates (the group that includes earthworms and leeches) are full hermaphrodites, although in a few leech species younger adults function as males and become female at maturity. All have well-developed gonads, and all copulate. Earthworms store their partners' sperm in spermathecae (\"sperm stores\") and then the clitellum produces a cocoon that collects ova from the ovaries and then sperm from the spermathecae. Fertilization and development of earthworm eggs takes place in the cocoon. Leeches' eggs are fertilized in the ovaries, and then transferred to the cocoon. In all clitellates the cocoon also either produces yolk when the eggs are fertilized or nutrients while they are developing. All clitellates hatch as miniature adults rather than larvae.\n\nCharles Darwin's book The Formation of Vegetable Mould through the Action of Worms (1881) presented the first scientific analysis of earthworms' contributions to soil fertility. Some burrow while others live entirely on the surface, generally in moist leaf litter. The burrowers loosen the soil so that oxygen and water can penetrate it, and both surface and burrowing worms help to produce soil by mixing organic and mineral matter, by accelerating the decomposition of organic matter and thus making it more quickly available to other organisms, and by concentrating minerals and converting them to forms that plants can use more easily. Earthworms are also important prey for birds ranging in size from robins to storks, and for mammals ranging from shrews to badgers, and in some cases conserving earthworms may be essential for conserving endangered birds.\n\nTerrestrial annelids can be invasive in some situations. In the glaciated areas of North America, for example, almost all native earthworms are thought to have been killed by the glaciers and the worms currently found in those areas are all introduced from other areas, primarily from Europe, and, more recently, from Asia. Northern hardwood forests are especially negatively impacted by invasive worms through the loss of leaf duff, soil fertility, changes in soil chemistry and the loss of ecological diversity. Especially of concern is Amynthas agrestis and at least one state (Wisconsin) has listed it as a prohibited species.\n\nEarthworms make a significant contribution to soil fertility. The rear end of the Palolo worm, a marine polychaete that tunnels through coral, detaches in order to spawn at the surface, and the people of Samoa regard these spawning modules as a delicacy. Anglers sometimes find that worms are more effective bait than artificial flies, and worms can be kept for several days in a tin lined with damp moss. Ragworms are commercially important as bait and as food sources for aquaculture, and there have been proposals to farm them in order to reduce over-fishing of their natural populations. Some marine polychaetes' predation on molluscs causes serious losses to fishery and aquaculture operations.\n\nAccounts of the use of leeches for the medically dubious practise of blood-letting have come from China around 30 AD, India around 200 AD, ancient Rome around 50 AD and later throughout Europe. In the 19th century medical demand for leeches was so high that some areas' stocks were exhausted and other regions imposed restrictions or bans on exports, and Hirudo medicinalis is treated as an endangered species by both IUCN and CITES. More recently leeches have been used to assist in microsurgery, and their saliva has provided anti-inflammatory compounds and several important anticoagulants, one of which also prevents tumors from spreading.\n\nSince annelids are soft-bodied, their fossils are rare. Polychaetes' fossil record consists mainly of the jaws that some species had and the mineralized tubes that some secreted. Some Ediacaran fossils such as Dickinsonia in some ways resemble polychaetes, but the similarities are too vague for these fossils to be classified with confidence. The small shelly fossil Cloudina, from 549 to 542 million years ago, has been classified by some authors as an annelid, but by others as a cnidarian (i.e. in the phylum to which jellyfish and sea anemones belong). Until 2008 the earliest fossils widely accepted as annelids were the polychaetes Canadia and Burgessochaeta, both from Canada's Burgess Shale, formed about 505 million years ago in the early Cambrian. Myoscolex, found in Australia and a little older than the Burgess Shale, was possibly an annelid. However, it lacks some typical annelid features and has features which are not usually found in annelids and some of which are associated with other phyla. Then Simon Conway Morris and John Peel reported Phragmochaeta from Sirius Passet, about 518 million years old, and concluded that it was the oldest annelid known to date. There has been vigorous debate about whether the Burgess Shale fossil Wiwaxia was a mollusc or an annelid. Polychaetes diversified in the early Ordovician, about 488 to 474 million years ago. It is not until the early Ordovician that the first annelid jaws are found, thus the crown-group cannot have appeared before this date and probably appeared somewhat later. By the end of the Carboniferous, about 299 million years ago, fossils of most of the modern mobile polychaete groups had appeared. Many fossil tubes look like those made by modern sessile polychaetes  , but the first tubes clearly produced by polychaetes date from the Jurassic, less than 199 million years ago.\n<Assistant>Noted. I'll remember these details.", "[Dialogue between User and Assistant on 2024-01-10 00:00]\n<User>Here's some valuable information I collected:\nThe earliest good evidence for oligochaetes occurs in the Tertiary period, which began 65 million years ago, and it has been suggested that these animals evolved around the same time as flowering plants in the early Cretaceous, from 130 to 90 million years ago. A trace fossil consisting of a convoluted burrow partly filled with small fecal pellets may be evidence that earthworms were present in the early Triassic period from 251 to 245 million years ago. Body fossils going back to the mid Ordovician, from 472 to 461 million years ago, have been tentatively classified as oligochaetes, but these identifications are uncertain and some have been disputed.\n<Assistant>Noted. I'll remember these details."]
[{"question": "How much of a Siboglinidae's weight is symbiotic bacteria?", "answer": "15%"}, {"question": "Which subtype of annelids includes most marine worms?", "answer": "polychaetes"}, {"question": "How many stages are there in annelids' waste filtration?", "answer": "two"}, {"question": "Where were \"stacks\" created with the LaserStack software used?", "answer": "in education"}, {"question": "Broadcast in Hong Kong used which standard formatting?", "answer": "PAL standard"}, {"question": "What is an annelid's cuticle made of?", "answer": "collagen"}, {"question": "Since 1997, what are leeches seen as a subgroup of?", "answer": "oligochaetes"}, {"question": "When did Rome begin using leeches?", "answer": "50 AD"}, {"question": "How do annelids withdraw from danger?", "answer": "shortening their bodies"}, {"question": "How old were the fossils of Canadia and Burgessochaeta found in Canada?", "answer": "505 million years"}, {"question": "What does 'coelom' mean?", "answer": "(body cavity"}, {"question": "In what year was Sega's AStron Belt released?", "answer": "1983"}, {"question": "When did India begin using leeches?", "answer": "200 AD"}, {"question": "Did MUSE have a large or small target market, even in Japan?", "answer": "tiny"}, {"question": "What era did oligochaetes evolve in?", "answer": "early Cretaceous"}, {"question": "What are the nuchal organs thought to do?", "answer": "chemosensors"}, {"question": "In addition to scratches and rot, what other common LaserDisc issue was to be eliminated by MUSE discs?", "answer": "Crosstalk"}, {"question": "What annelids are hermaphrodites?", "answer": "Oligochaetes"}, {"question": "What percent vertical resolution increase did Squeeze LDs feature over regular widescreen LDs?", "answer": "33%"}, {"question": "What type of annelid tunnels through coral?", "answer": "Palolo worm"}, {"question": "Where was Myoscolex found?", "answer": "Australia"}, {"question": "What covers an annelid's exterior?", "answer": "a cuticle"}, {"question": "Which collector group highly values LaserDisc for their rareness?", "answer": "movie enthusiasts"}, {"question": "What percent of polychaetes produce yolk-rich eggs?", "answer": "14%"}, {"question": "What are cilia?", "answer": "fine muscle-powered hairs"}, {"question": "What are most polychaetes' eggs covered in?", "answer": "jelly"}, {"question": "What are annelids' body cavities separated from each other by?", "answer": "vertical mesenteries"}, {"question": "In what year did the Doomsday project occur?", "answer": "1986"}, {"question": "What does 'pygidium' mean?", "answer": "little tail"}, {"question": "What type of pigment is dissolved in annelids' blood?", "answer": "Respiratory"}, {"question": "How much of near-shore marine annelids are burrowing?", "answer": "up to a third"}, {"question": "LaserDisc was the first format to provide what type of releases to consumers?", "answer": "\"Special Edition\""}, {"question": "What annelid system combines both filtration states in one organ?", "answer": "protonephridia"}, {"question": "What is movement by ripples called?", "answer": "peristalsis"}, {"question": "Which subtype of annelids includes earthworms?", "answer": "oligochaetes"}, {"question": "What was the internal name for \"laser rot\" within LD processing plants?", "answer": "\"color flash\""}, {"question": "How many species of polychaetes have known lifecycles?", "answer": "about 25%"}, {"question": "How old is the earliest annelid fossil?", "answer": "518 million years ago"}, {"question": "Which format was more popular in high humidity areas such as Singapore?", "answer": "LaserDiscs"}, {"question": "What type of bait do experienced anglers prefer?", "answer": "spawning modules"}, {"question": "What layer is under the epidermis?", "answer": "the dermis"}, {"question": "Which format used in DVDs has built-in error correction?", "answer": "digital MPEG-2"}, {"question": "How much did a LD cost in Hong Kong in the 1990s?", "answer": "USD100"}, {"question": "Which artist released a music video and three audio tracks on CD-V in 1989?", "answer": "David Bowie"}, {"question": "What type of annelid fossils have been found from the mid Ordovician period?", "answer": "oligochaetes"}, {"question": "The Doomsday Project discs used which formatting?", "answer": "CAV"}, {"question": "What end of annelids with well-developed segmentation has muscles that act like hearts?", "answer": "front"}, {"question": "What substandard product was used in LD manufacturing that caused \"laser rot\"?", "answer": "adhesive"}, {"question": "What are most polychaetes lacking for reproduction?", "answer": "permanent gonads"}, {"question": "What blocks the Siboglinidae's gut?", "answer": "a swollen lining"}, {"question": "What type of annelids have nuchal organs?", "answer": "polychaetes"}, {"question": "Could the 16:9 aspect ratio be easily resized by a normal LD player, or was the image significantly distorted?", "answer": "distorted"}, {"question": "Which movie was released twice on Squeeze LD?", "answer": "Terminator 2"}, {"question": "What are coelomata?", "answer": "body cavities"}, {"question": "In what year did ODC develop the Recordable LaserVision Disc?", "answer": "1984."}, {"question": "How many EditDroid systems were ever built?", "answer": "24"}, {"question": "What improvement was added to Terminator 2's second Squeeze LD release?", "answer": "THX certified"}, {"question": "What color were regular LaserDiscs, in contrast to RLVs blueish purple hues?", "answer": "silver mirror"}, {"question": "By 1990, how many American homes were estimated to use LD?", "answer": "nearly one million"}, {"question": "In which format does crosstalk generally not occur?", "answer": "CAV"}, {"question": "What was the vertical blanking interval used for in LaserDiscs, preventing Macrovision signal to be implemented?", "answer": "internal timing"}, {"question": "What annelid group includes leeches and earthworms?", "answer": "clitellates"}, {"question": "In what year were LD jukeboxes created?", "answer": "1985"}, {"question": "What are phrynges?", "answer": "throats"}, {"question": "What do some polychaetes eat that has been causing problems?", "answer": "molluscs"}, {"question": "What are ganglia?", "answer": "local control centers"}, {"question": "What were VSDs lacking that CD-Vs included?", "answer": "audio CD tracks"}, {"question": "What term means 'little eyes'?", "answer": "ocelli"}, {"question": "Where did most of the current earthworms in glacial areas come from?", "answer": "Europe"}, {"question": "What can coelomocyte cells defend against?", "answer": "parasites and infections"}, {"question": "How many years did it take Blu-ray and HD-DVD players to duplicate MUSE technology?", "answer": "almost 15 years"}, {"question": "What is the largest bird that eats earthworms?", "answer": "storks"}, {"question": "Who created LD Jukeboxes in 1985?", "answer": "Jasmine Multimedia"}, {"question": "What is LaserDisc playback quality dependent on?", "answer": "hardware quality"}, {"question": "What do metanephridia remove?", "answer": "soluble waste products"}, {"question": "What do some non-single-sex polychaetes do?", "answer": "change sex"}, {"question": "What releases sperm from annelids?", "answer": "nephridia"}, {"question": "What type of forests can be hurt by invasive worms?", "answer": "Northern hardwood forests"}, {"question": "How many coelomata do leeches have?", "answer": "two"}, {"question": "How do annelids normally reproduce?", "answer": "sexual reproduction"}, {"question": "How cheaply could an older LaserDisc player be purchased in the 1990s?", "answer": "$25"}, {"question": "Is LaserDisc quality consistent or inconsistent between player brands?", "answer": "inconsistency"}, {"question": "Were VSDs or CD-Vs all digital and also playable on DVD players?", "answer": "VSDs"}, {"question": "Where do leeches move their eggs to?", "answer": "the cocoon"}, {"question": "What annelids make a cocoon in a ring around themselves?", "answer": "Oligochaetes"}, {"question": "What annelid's rear end do Samoans like to eat?", "answer": "Palolo worm"}, {"question": "What annelids' jaws are being studied by engineers?", "answer": "Ragworms"}, {"question": "What does 'nuchal' mean?", "answer": "on the neck"}, {"question": "With what operating ratio would MUSE Discs operate?", "answer": "5:3"}, {"question": "In contrast to broadcast, which format did consumers use in Hong Kong?", "answer": "NTSC"}, {"question": "What type of worm have there been proposals to farm?", "answer": "Ragworms"}, {"question": "What quality made LDs a consideration for videogames in the 1980s and 1990s?", "answer": "instant-access capability"}, {"question": "What do annelids without blood vessels do to remove waste?", "answer": "protonephridia"}, {"question": "What lines the coelomata of leeches?", "answer": "mesothelium"}, {"question": "What type of annelids have limb-like parapodia?", "answer": "polychaetes"}, {"question": "Which of Apple's programming languages allowed users to ceatively manipulate LaserDiscs?", "answer": "HyperCard"}, {"question": "What hair-like extensions do chetoblasts make?", "answer": "microvilli"}, {"question": "Which commercial company was LaserStack's most successful distributor?", "answer": "Voyager"}, {"question": "When did the Tertiary period begin?", "answer": "65 million years ago"}, {"question": "When did leeches begin being used for blood-letting?", "answer": "30 AD"}]