Several competing models, although correctly dealing with the conformation of each individual peptide chain, gave way to the triple-helical " Madras " model, which provided an essentially correct model of the molecule's quaternary structure although this model still required some refinement .< ref > The packing structure of collagen has not been defined to the same degree outside of the fibrillar collagen types, although it has been long known to be hexagonal or quasi-hexagonal.

Several types of military bridging vehicles have existed through the years.

Several types of chocolate can be distinguished.

Figure 8: Several types of diodes.

Several laboratory scale techniques for distillation exist ( see also distillation types ).

Several thousand patients have been treated with various types of tumours.

Several types of brain lesions can occur in individuals with TSC and 60 %-90 % of people with TSC develop epilepsy.

Several grappling styles like Judo, Shoot wrestling, Catch wrestling, Brazilian jiu-jitsu, Sambo and several types of wrestling including Freestyle and Greco-Roman have gained global popularity.

Several types are existent in Qing dynasty and used in dishes of stewing hams ( 火腿炖肘子 ), and vegetables, or for a wide variety of soup and important soup stocks.

Several types of FDA approved vacuum therapy devices are available with a doctor's prescription.

Several types of wild greens, known collectively as chwinamul ( such as Aster scaber ), are a popular dish, and other wild vegetables such as bracken fern shoots ( gosari ) or Korean bellflower root ( doraji ) are also harvested and eaten in season.

Several different types of light sources exist, each having different properties that affect their appropriateness for certain tasks, particularly efficiency and spectral power distribution.

Several types of molecules are particularly important during morphogenesis.

Several types of cell adhesion molecules are known and one major class of these molecules are cadherins.

Several types of " mania " such as kleptomania and pyromania are related more closely to obsessive-compulsive disorder than to bipolar disorder, depending on the severity of these disorders.

Several types of plasmid addiction systems ( toxin / antitoxin, metabolism-based, ORT systems ) were described in the literature and used in biotechnical ( fermentation ) or biomedical ( vaccine therapy ) applications.

Several cell types may be present in the epidermis.

Several types of RNA can downregulate gene expression by being complementary to a part of an mRNA or a gene's DNA.

Several types of visual prosthesis are in development or trials in humans, and one device has been approved for sale in the European market.

Several types of random samples are simple random samples, systematic samples, stratified random samples, and cluster random samples.

Several types of mushroom ( het ) also feature in Thai cuisine such as straw mushrooms ( het fang ) and white jelly fungus ( het hu nu khao ).

) Several types of naval " torpedo " were developed and deployed, most often by the Confederates, who faced a severe disadvantage in more traditional warfare methods.

Several types of fish can detect ultrasound.

Several types of pumps may be used in sequence or in parallel.

Several types have technological importance, for example, in liquid crystal displays.

Several existing pieces of music were adapted to the poem.

Several of Milne's children's poems were set to music by the composer Harold Fraser-Simson.

Several annual music festivals take place in Davenport, including the Mississippi Valley Blues Festival, The Mississippi Valley Fair, and the Bix Beiderbecke Memorial Jazz Festival.

Several techniques are used by DJs as a means to better mix and blend recorded music.

Several hours of music were prepared for it, including Bach fugues, all of Mozart's Eine kleine Nachtmusik, Christmas carols, and numerous popular songs.

Several rock historians have claimed that rock and roll was one of the first music genres to define an age group.

Several notable music artists died of unnatural causes in the 1980s.

Several songs were cut from the Season 1 DVD release due to music licensing issues.

Several music factions wanted to claim the Jordan sound as its own and encouraged him to follow in the track of other artists.

Several passages have leanings towards folk music, as manifested in Austrian serenades.

Several cafes feature live music, a few of which specialize in jazz music, including Jazzcafe De Spieghel on the Peperstraat.

Several bandmembers are currently active in UK music industry bodies – amongst them the FAC, whilst Mark Kelly was elected in November 2009 to both the Performer and Main Boards of the UK's PPL.

Several references to The Cure and their music have been made in popular culture.

Several music cues from the program are still used today as background music during prize descriptions on The Price Is Right.

Several people on The Current's initial staff are well known in the area for previous work at stations that highlight music from Minnesota and the Upper Midwest.

Several of Stein's writings have been set to music by composers, including Virgil Thomson's operas Four Saints in Three Acts and The Mother of Us All, and James Tenney's setting of Rose is a rose is a rose is a rose as a canon dedicated to Philip Corner, beginning with " a " on an upbeat and continuing so that each repetition shuffles the words, e. g. " a / rose is a rose / is a rose is / a rose is a / rose.

Several characters are based on real country music figures: Henry Gibson's Haven Hamilton is a composite of Roy Acuff, Hank Snow, and Porter Wagoner ; Ronee Blakely's Barbara Jean is based on Loretta Lynn ; the black country singer Tommy Brown ( played by Timothy Brown ) is based on Charley Pride ; and the feuding folk trio is based on Peter, Paul and Mary ; within the trio, the married couple of Bill and Mary were inspired by Bill Danoff and Taffy Nivert, who later became Starland Vocal Band .< ref >

Several New York musicians who had already been performing Cuban dance music for decades when salsa was popularized initially scoffed at the term.

Several prominent hip hop producers, such as DJ Premier, and RjD2 also favour retaining the lo-fidelity characteristics of the records they sample in order to achieve a hard, unpolished and " uncut " sound in their own music.

Several record albums of original soundtrack music from the series were released, some having alternate theme music for the series that was never used.

" Funk, jazz, and Brazilian music were inspirations, and the sounds of minimalist composers Philip Glass and Steve Reich can be found on 1999's Cobra and Phases Group .... Several critics have commented that the band's later work, like Instant 0 in the Universe ( 2003 ) and Margerine Eclipse ( 2004 ), sound similar to their guitar-driven earlier style.

Several critics have said that Stereolab lacked stage presence, arguing that Sadier's vocal delivery was too subdued and that the band tended to play instead of perform its music.