About the shape Image Helix.svg thumb The helix cos t , sin t , t from t 0 to 4 with arrowheads showing ... of a foldamer folded molecular helix reported by Jean Marie Lehn Lehn and coworkers in Helv. Chim. Acta., 2003, 86, 1598 1624. Image DirkvdM natural spiral.jpg thumb A natural left handed helix, made by a Vine climber plant. A helix pl helixes or helices is a type of Differentiable manifold smooth ... springs and the handrails of spiral staircases. A filled in helix for example, a spiral ramp is called ... , as the DNA molecule is formed as double helix two intertwined helices , and many protein s have helical substructures, known as alpha helix alpha helices . The word helix comes from the Greek language ... along the helix s axis, if a clockwise screwing motion moves the helix away from the observer, then it is called a right handed helix if towards the observer then it is a left handed helix. Handedness or chirality mathematics chirality is a property of the helix, not of the perspective a right handed helix cannot be turned or flipped to look like a left handed one unless it is viewed in a mirror, and vice versa. Most hardware screw thread s are right handed helices. The alpha helix in biology ... is left handed. The pitch of a helix is the width of one complete helix turn, measured parallel to the axis of the helix. A double helix consists of two typically congruent helices with the same axis ... Helix by S ndor Kabai, Wolfram Demonstrations Project . ref A conic helix may be defined as a spiral ... Point amusement park. A circular helix, i.e. one with constant radius has constant band curvature and constant Torsion of curves torsion . A curve is called a general helix or cylindrical helix ref O ... line in space. A curve is a general helix if and only if the ratio of curvature to Torsion ... description In mathematics , a helix is a Differential geometry of curves curve in 3 dimension ... coordinates defines a helix ref MathWorld urlname Helix title Helix ref math x t cos t , , math ... more details
other uses Helix disambiguation Infobox building name The Helix image The helix2.JPG building type Theatre architectural style structural system location Dublin , Ireland completion date 2002 opened main contractor architect Andrzej Wejchert & Danuta Kornaus Wejchert structural engineer The Helix is a building on the Dublin City University campus between Glasnevin and Whitehall on Dublin s Northside Dublin Northside , originally planned to be called the Aula Maxima . It was completed in 2002, and it is described ... arts shows. The Helix has three areas for live performances The Mahony Hall 1260 seats , The Theatre 450 seats , and The Space 150 seats . About Deleted image removed Image Irelandscape helix reception.jpg 220px thumb right Foyer, Ground floor At a cost of Euro 36.5 million, The Helix is an Arts ... to performance can be changed to allow alternative uses. The Helix has been host to world class .... The Helix has been host to many orchestras from around the world, including opera singers such as Dame ... also played the venue. The Helix has been host to a number of television programmes including The Dunphy ... there. It is currently home to the National Chamber Choir of Ireland . The Helix has also hosted RT Radio 1 s leading arts programme, Rattlebag . The Helix was awarded the Opus Building of the Year Award in 2003. It has been recently reported the The Helix is going through massive financial difficulties ... can seat 150. The Gallery The Gallery, situated on the top floor of The Helix is a dedicated exhibition ... http classicstageireland.com Classic Stage Ireland Based in The Helix http www.irelandscape.com display ... sets 970534 Photographs of The Helix from flickr.com http www.flickr.com photos griangrafanna tags thehelix Photographs of The Helix from flickr.com different tag Theatres in Ireland RT Performing Groups coord 53 23 11 N 6 15 34 W type landmark display title DEFAULTSORT Helix Category ... The Helix Category Buildings and structures completed in 2002 Category Theatres in Dublin city ... more details
wiktionary helix A helix is a spiral like shape. Helix may also refer to TOCright Publications Helix comics , a 1996 1998 DC comics imprint Helix newspaper Helix newspaper , a 1960s underground publication Helix Magazine , a Central Connecticut State University publication Helix , a novel by Eric Brown writer Eric Brown Helix, a team of super villains in the Infinity Inc. comic series Computing Helix cipher Helix database Helix multimedia project Other uses Helix band Helix company , a UK scholastic stationery manufacturer Helix ear Helix gastropod Helix gastropod , a genus of snails Helix video game Helix video game Helix film Helix film , also known as Innocent The Helix , a performance space in Ireland The Helix Bridge , Singapore Honda Helix , a scooter Helix High School Helix Nebula DJ Helix , a DJ from the United Kingdom Kamov Ka 27 , a helicopter, NATO reporting name Helix New Jersey Route 495 or The Helix, a roadway approaching the Lincoln Tunnel A recurring element in the Mythology of Heroes Helix mythology of Heroes See also Helix SF , an online magazine disambig cs Helix de Helix Begriffskl rung es H lice eo Helico apartigilo fr H lice homonymie it Elica disambigua nl Helix no Helix andre betydninger pt Helix fi Helix ... more details
Italic title Taxobox name Bulbophyllum helix image regnum Plantae unranked divisio Angiosperms unranked classis Monocots ordo Asparagales familia Orchidaceae subfamilia Epidendroideae genus Bulbophyllum species Bulbophyllum helix binomial binomial authority synonyms Bulbophyllum helix is a species of orchid in the genus Bulbophyllum . References http bulbophyllum checklist.bulbophyllum.at The Bulbophyllum Checklist http www.orchidspecies.com indexbulb.htm The Internet Orchid Species Photo Encyclopedia DEFAULTSORT Bulbophyllum Helix Category Bulbophyllum helix Bulbophyllum stub az Bulbophyllum helix vi Bulbophyllum helix ... more details
Infobox Anatomy Name Helix ear Latin GraySubject 229 GrayPage 1033 Image Gray904.png Caption The pinna anatomy auricula . Lateral surface. Image2 Gray908.png Caption2 Horizontal section through left ear upper half of section. Helix labeled at bottom right. System Precursor MeshName MeshNumber DorlandsPre h 04 DorlandsSuf 12411025 The prominent rim of the pinna anatomy auricula is called the helix . Where the helix turns downward behind, a small tubercle is frequently seen the Darwin s tubercle auricular tubercle of Darwin . Additional images gallery Image Gray906.png The muscles of the auricula. gallery Additional images NormanAnatomy lesson3 NormanAnatomyFig externalear 3 Gray s Auditory system Category Ear anatomy stub de Helix Ohr es H lice o do nl Helix oor no Helix re ... more details
Taxobox image Helix lucorum 2.jpg image caption live specimen of Helix lucorum status NE status ref ref IUCN 2008. 2008 IUCN Red List of Threatened Species. www.iucnredlist.org . Downloaded on 16 April 2009. ref regnum Animal ia phylum Mollusca classis Gastropoda familia Helicidae genus Helix genus Helix subgenus Helix species H. lucorum binomial Helix lucorum binomial authority Carl Linnaeus Linnaeus , 1758 Helix lucorum is a species of large, edible, air breathing land snail or escargot , a Terrestrial animal terrestrial pulmonate gastropod mollusk in the family biology family Helicidae , the typical snails. Synonyms Numerous Synonym taxonomy synonyms exist for Helix lucorum Helix anaphora Westerlund, 1889 Helix annosa Mascarini, 1892 Helix atrocincta Bourguignat, 1883 Helix candida Mascarini, 1892 Helix elongata Bourguignat, 1860 Helix nigrozonata Bourguignat, 1883 Helix presbensis Kobelt, 1905 Helix rypara Bourguignat, 1883 Helix straminea Briganti, 1825 Helix straminiformis Bourguignat, 1876 Helix virago Bourguignat, 1883 Helix yleobia Bourguignat, 1883 ref name cited 5 May 2007 http www.faunaeur.org full results.php?id 277677 cited 5 May 2007 ref Description Image Helix lucorum.jpg left thumb The gastropod shell shell of Helix lucorum This species of snail makes and uses love dart s. The size of the egg is 4.4 mm. ref name Barker Heller J. Life History Strategies . in Barker G. M. ed. http books.google.com books?id WlvX 9Wt0toC&hl The biology of terrestrial molluscs . CABI ..., page 12 and Appendix 2. ref References reflist External links commons Helix lucorum http szmn.sbras.ru picts Mollusca Helix lucorum.htm http www.jaxshells.org 818d.htm http www.faunaeur.org full results.php?id 277677 http www.helicicultura.es TODO SOBRE CARACOLES Edible molluscs Category Helix Category Edible molluscs Helicidae stub de Gestreifte Weinbergschnecke es Helix lucorum fr Helix lucorum nl Helix lucorum ... more details
Italic title Taxobox name Calliotropis helix image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Seguenzioidea familia Calliotropidae subfamilia genus Calliotropis species C. helix binomial Calliotropis helix binomial authority Vilvens, 2007 synonyms ref synonyms Calliotropis helix is a species of sea snail , a marine gastropod mollusk in the family biology family Calliotropidae . ref name WoRMS WRMS species 446316 Calliotropis helix Vilvens, 2007 18 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Calliotropis Helix Category Calliotropidae Calliotropidae stub vi Calliotropis helix ... more details
italictitle Taxobox name Helix obruta image status VU status system IUCN2.3 regnum Animalia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora br informal group Sigmurethra superfamilia Helicoidea familia Helicidae genus Helix species H. obruta binomial Helix obruta binomial authority Morelet, 1860 synonyms Helix obruta is a species of large, edible, air breathing land snail , a terrestrial animal terrestrial pulmonate gastropod mollusk in the family Helicidae , the typical snails. This species is Endemism endemic to Portugal . References reflist Frias Martin, A. 1996. http www.iucnredlist.org search details.php 9845 all Helix obruta . http www.iucnredlist.org 2006 IUCN Red List of Threatened Species. Downloaded on 7 August 2007. Category Fauna of Portugal Category Helix Helicidae stub az Helix obruta es Helix obruta pt Helix obruta ... more details
In geometry , a triple helix plural triple helices is a set of three congruent geometrical helix helices with the same axis, differing by a translation along the axis. Structures in the form of a triple helix include collagen helix peptide nucleic acid some types, not all triple stranded DNA biochem stub geometry stub Category Curves Category Geometric shapes Category Helices Category Protein structural motifs ... more details
italictitle Taxobox name Helix godetiana image status LR nt status system IUCN2.3 status ref ref Mylonas M. 1996 . http www.iucnredlist.org search details.php 9844 all Helix godetiana . http www.iucnredlist.org 2006 IUCN Red List of Threatened Species. Downloaded on 7 August 2007. ref regnum Animalia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora br informal group Sigmurethra superfamilia Helicoidea familia Helicidae genus Helix species H. godetiana binomial Helix godetiana binomial authority Wilhelm Kobelt Kobelt , 1878 ref de icon Wilhelm Kobelt Kobelt W. 1878 . Diagnosen neuer Arten . Jahrb cher der Deutschen Malakozoologischen Gesellschaft 5 http www.archive.org stream jahrbcherderde51878deut page 319 mode 1up 319 321. Frankfurt am Main. ref synonyms Helix godetiana is a species of large, air breathing land snail , a terrestrial animal terrestrial pulmonate gastropod mollusk in the family Helicidae , the typical snails. This species is Endemism endemic to List of non marine molluscs of Greece Greece . References reflist External links http www.animalbase.uni goettingen.de zooweb servlet AnimalBase home species?id 2975 Species summary for Helix godetiana Helicidae stub Category Helix az Helix godetiana es Helix godetiana pt Helix godetiana sr Helix godetiana ... more details
italictitle Taxobox name Helix texta image status EN status system IUCN2.3 status ref ref Heller J. 1996. http www.iucnredlist.org search details.php 9846 all Helix texta . http www.iucnredlist.org 2006 IUCN Red List of Threatened Species. Downloaded on 07 August 2007. ref regnum Animalia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora br informal group Sigmurethra superfamilia Helicoidea familia Helicidae genus Helix species H. texta binomial Helix texta binomial authority Mousson , 1861 synonyms Helix texta is a species of large, edible, air breathing land snail , a terrestrial animal terrestrial pulmonate gastropod mollusk in the family Helicidae , the typical snails. This species is Endemism endemic to List of non marine molluscs of Israel Israel . The size of the egg is 5.5 mm. ref name Barker Heller J. Life History Strategies . in Barker G. M. ed. http books.google.com books?id WlvX 9Wt0toC&hl The biology of terrestrial molluscs . CABI Publishing, Oxon, UK, 2001, ISBN 0 85199 318 4. 1 146, cited page 428. ref References reflist Category Helix Helicidae stub az Helix texta ca Helix texta es Helix texta pt Helix texta sr Helix texta ... more details
italictitle Taxobox name Helix goderdziana image image caption Helix goderdziana regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora br informal group Sigmurethra superfamilia Helicoidea familia Helicidae subfamilia genus Helix gastropod Helix subgenus species H. goderdziana binomial Helix goderdziana binomial authority Mumladze, Tarkhnishvili & Pokryszko, 2008 ref name Mumladze Mumladze L., Tarkhnishvili D. & Pokryszko B.M. 2008. A new species of the genus Helix from the Lesser Caucasus sw Georgia . Journal of Conchology, volume 39, part 5, page 483, published June 2008. http www.conchsoc.org resources show abstract 39.php?id 20 20 20 20 20 20 20 20 20 20 20 20147 abstract ref synonyms Helix goderdziana is a species of large air breathing land snail , a terrestrial animal terrestrial pulmonate gastropod mollusk in the family Helicidae , the typical snail. This is the largest species in the genus Helix . ref name Mumladze Distribution This species occurs in the Lesser Caucasus in southwestern List of non marine molluscs of Georgia country Georgia ref name Mumladze Biotope This snail lives in humid montane forest ref name Mumladze References reflist Category Helix Category Animals described in 2008 Helicidae stub az Helix goderdziana ... more details
DISPLAYTITLE 3 sub 10 sub helix Image 3 10 helix neg49 neg26 sideview.png thumb right 250px Side view of an 3 sub 10 sub helix of alanine residues in atom ic detail. Two hydrogen bonds to the same peptide group are highlighted in magenta the oxygen hydrogen distance is 1.83 183 pm . The protein chain runs upwards, i.e., its N terminus is at the bottom and its C terminus at the top of the figure. Note that the sidechains point slightly downwards , i.e., towards the N terminus. A 3 sub 10 sub helix is a type of secondary structure found rarely in protein s. Structure The amino acids in a 3 sub 10 sub helix are arranged in a right handed helix helical structure. Each amino acid corresponds to a 120 turn in the helix i.e., the helix has three residues per turn , and a translation of 2.0 0.2 nm along the helical axis, and has 10 atoms in the ring formed by making the hydrogen bond. Most importantly, the amine N H group of an amino acid forms a hydrogen bond with the carbonyl C O group of the amino acid three residues earlier this repeated i 3 i hydrogen bonding defines a 3 sub 10 sub helix. Similar structures include the Alpha helixhelix i 4 i hydrogen bonding and the Pi helixhelix i 5 i hydrogen bonding . Image 310 helix topview.png thumb left 225px Top view of the same helix shown to the right ..., corresponding to 3.0 amino acid amino acid residues per turn of the helix. Residues in 3 sub ... residue sum to roughly 75 . For comparison, the sum of the dihedral angles for an helix is roughly 105 , whereas that for a helix is roughly 125 . The general formula for the rotation angle per residue of any polypeptide helix with trans isomers is given by the equation math 3 cos Omega 1 4 cos 2 left frac varphi psi 2 right . math See also alpha helix pi helix secondary structure References ... Category Protein structural motifs Category Helices protein stub de 3 Helix es H lice 310 ja ... more details
Image Lambda repressor 1LMB.png 200px thumb The &lambda repressor of bacteriophage lambda employs a helix turn helix left green to bind DNA right blue and red . In protein s, the helix turn helix HTH is a major structural motif capable of binding DNA . It is composed of two alpha helix helices joined ... not be confused with the helix loop helix domain. ref name pmid2644244 cite journal author Brennan RG, Matthews BW title The helix turn helix DNA binding motif. journal J Biol Chem year 1989 volume 264 issue 4 pages 1903 6 pmid 2644244 doi pmc url ref Discovery The discovery of the helix turn helix motif was based on similarities between several genes encoding transcription regulatory proteins ... Nature year 1982 volume 298 issue 5873 pages 443 7 pmid 7088190 doi pmc url ref Function The helix turn helix motif is a DNA binding motif. The recognition and binding to DNA by helix turn helix ... at the C terminus . In most cases, such as in the Cro repressor, the second helix contributes most to DNA recognition, and hence it is often called the recognition helix . It binds to the major ... interactions with exposed base pair bases . The other helix stabilizes the interaction between protein ... The recognition helix and its preceding helix always have the same relative orientation. ref name ... of helix turn helix motifs Several attempts have been made to classify the helix turn helix motifs based ..., Iyer LM title The many faces of the helix turn helix domain transcription regulation and beyond. journal ... The tri helical helix turn helix motif is the simplest helix turn helix motif. It consists only ..., Sarai A et al. title Solution structure of a DNA binding unit of Myb a helix turn helix related motif ... helix turn helix motif has an additional C terminal helix compared to the tri helical motifs. These include the LuxR type DNA binding HTH domain found in bacterial transcription factors and the helix turn helix motif found in the TetR repressors. ref name pmid8153629 cite journal author Hinrichs W ... more details
italictitle Taxobox name Helix melanostoma image image caption shells of Helix melanostoma status status ref regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora superfamilia Helicoidea familia Helicidae genus Helix gastropod Helix species H. melanostoma binomial Helix melanostoma binomial authority Jacques Philippe Raymond Draparnaud Draparnaud , 1801 ref Jacques Philippe Raymond Draparnaud Draparnaud J. P. R. 1801 . Tableau des mollusques terrestres et fluviatiles de la France . pp. 1 2 , 1 116. Montpellier, Paris. ref Helix melanostoma is a species of air breathing land snail , a Terrestrial animal terrestrial pulmonate gastropod mollusk in the family biology family Helicidae , the typical snails. Distribution List of non marine molluscs of France France ref http www.onem france.org escargots wakka.php?wiki HelixMelanostomaCarto accessed 22 June 2010. ref References reflist External links http www.animalbase.uni goettingen.de zooweb servlet AnimalBase home species?id 1602 Category Helix Helicidae stub az Helix melanostoma fr Helix melanostoma ... more details
unreferenced date June 2011 A helix building is a small structure at the base of a longwave or mediumwave radio transmitter . Within, there are capacitor s and Inductor coil s for coupling the signal from the feed cable to the Antenna radio antenna . Active components such as amplifier s are usually not housed in a helix building. The interior of the helix building is typically covered with copper or aluminium, in order to control stray radiation. For safety, helix buildings must be secured, due to the dangerously high voltages which may be present inside. The helix building, which may be a simple switchbox for small transmitters, is sometimes also the base of a mast radiator . See also Radio Frequency Power Transmission Category Radio terminology radio comm stub ... more details
italictitle Taxobox name Helix mazzullii image Monte Cofano Cantareus mazzullii 0038.JPG status VU status system IUCN2.3 status ref ref Manganelli, G. 2000. http www.iucnredlist.org search details.php 40099 all Cantareus mazzullii . http www.iucnredlist.org 2006 IUCN Red List of Threatened Species. Downloaded on 06 August 2007. ref regnum Animalia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora br informal group Sigmurethra superfamilia Helicoidea familia Helicidae genus Helix genus Helix species H. mazzullii binomial Helix mazzullii binomial authority De Cristofori & Jan, 1832 synonyms Cantareus mazzullii br Cornu mazzullii Helix mazzullii , also known as Cantareus mazzullii or Cornu mazzullii , is a species of large, edible, air breathing land snail , a terrestrial animal terrestrial pulmonate gastropod mollusk in the family Helicidae , the typical snails. This species is Endemism endemic to List of non marine molluscs of Italy Italy . It is threatened by habitat loss . References reflist External links commonscat Helix mazzullii http www.animalbase.uni goettingen.de zooweb servlet AnimalBase home species?id 2741 Animal Base info Category Helix Category Fauna of Italy Category Endemic fauna of Italy Helicidae stub az Helix mazzullii es Cantareus mazzullii it Cornu mazzullii pt Cantareus mazzullii ... more details
Infobox company name Helix logo File Helix logo.jpg 250px caption type Privately held company Private traded as genre Only used with media and publishing companies fate predecessor successor foundation 1887 founder defunct location city Lye, West Midlands location country United Kingdom location locations area served Worldwide key people industry Stationery products services revenue operating income net income aum Only used with financial services companies assets equity owner num employees parent divisions subsid homepage http www.helix.co.uk index.php Helix footnotes intl Helix is a family run United Kingdom based manufacturer of scholastic stationery . It currently employes 75 people, and exports to over 65 countries, with offices in Chicago and Hong Kong and with UK headquarters based in Lye, West Midlands . History Helix was established in 1887, under the name The Universal Woodworking Company Ltd. , manufacturing wooden Ruler rules and metal laboratory apparatus.In 1894 it patented the Compass drafting drawing compass , and with it, launched the Helix brand, following on from the initial success of the compass and rule, in 1912 the companies first mathematical set was created and in 1935 the brand Helix Oxford was launched. 1955 saw the company become known as the Helix Universal ... again changed to its current name Helix International Ltd. . Brands Helix Splat and Tribe fashion stationery Helix Oxford high quality mathematical instruments and stationery Helix Technical technical ... 2012. The company made the following announcement, Over the last few months, the Directors of Helix have been working towards a financial restructuring with the aim of securing the future of the Helix brand, its business and employees. The administration is an integral part of this process and Helix ... to achieve our objective . We will, of course, keep you informed of developments as they occur. Helix Ltd 25th January 2012. External links http www.helix.co.uk index.php Helix UK company stub Category ... more details
A Polyproline Helix is a type of protein secondary structure , which occurs in proteins comprising repeating proline residues. A left handed polyproline II helix PPII , poly Pro II is formed when sequential ... bond s. Similarly, a more compact right handed polyproline I helix PPI , poly Pro I is formed ... likely to adopt the cis isomer. Polyproline II helix Image poly Pro II topview.png left thumb 200px Top view of a twenty residue poly Pro II helix, showing the three fold symmetry. The PPII helix is defined ... angle per residue of any polypeptide helix with trans isomers is given by the equation ..., dihedral angles into this equation yields almost exactly 120 , i.e., the PPII helix is a left handed helix since is negative with three residues per turn 360 120 3 . The rise per residue is approximately ... Side view of a poly Pro II helix, showing its openness and lack of internal hydrogen bonding. The PPII helix is relatively open and has no internal hydrogen bond ing, as opposed to the more common helical secondary structure s, the alpha helix and its relatives the 3 10 helix 3 sub 10 sub helix and the pi helix , as well as the beta helixhelix . The amide nitrogen and oxygen atoms are too far ... amino acid glycine . The analog of the poly Pro II helix in poly glycine is called the poly Gly II helix . Polyproline I helix Image poly Pro I sideview.png left thumb 200px Side view of the poly Pro I helix, showing its greater compaction. The poly Pro I helix is much denser than the PPII helix ..., but not identical to, those of the PPII helix. However, the PPI helix is a right handed helix and more ... helix is also much smaller, roughly 1.9 . Again, there is no internal hydrogen bonding in the poly Pro I helix, both because an H bond donor atom is lacking and because the amide nitrogen and oxygen ... thumb 200px Top view of a twenty residue poly Pro I helix, showing its non integer number of residues ... the PPII and PPI helix forms of poly proline are slow, due to the high activation energy of X ... more details
Image Helix angle.jpg thumb Helix Angle In mechanical engineering , a helix angle is the angle between any helix and an axial line on its right, circular cylinder or cone. ref name agma Citation isbn 1 ... s, helical gear s, and worm gear s. The helix angle references the axis of the cylinder, distinguishing it from the lead angle , which references a line perpendicular to the axis. Naturally, the helix angle is the geometric Complementary angles complement of the lead angle. The helix angle is measured in degrees. Concept In terms specific to screws, the helix angle can be found by unraveling the helix ... mechanical applications of the helix angle. File Helix angle v2.svg 300px The helix angle can be expressed as ref Shigley, p. 401. ref math mbox Helix angle arctan left frac 2 pi r m l right math ... The helix angle is crucial in mechanical engineering applications that involve Mechanical ... its use is much more widely spread. Screw File Efficiency vs helix angle.svg thumb 300px A plot of the efficiency of a screw versus the thread helix angle. Cutting a single helical groove into a screw ... thread screw provided that the helix angle is steeper, and a second thread is cut in the space between ... Hall, 2006. ref The helix may be cut either right hand or left hand. In screws especially, the helix ... frac phi 2 math math eta max frac 1 sin phi 1 sin phi math Where math alpha , math is the helix angle ... is controlled by the helix angle. The efficiency can be plotted versus the helix angle for a constant friction, as shown in the diagram to the right. The maximum efficiency is a helix angle between ... the thread, helix angle greater than 30 are rarely used. Moreover, above 30 the friction angle becomes smaller than the helix angle and the nut is no longer self locking and the mechanical advantage ... In helical and worm gears, the helix angle denotes the standard pitch circle unless otherwise specified. ref name agma Application of the helix angle typically employs a magnitude ranging from 15 to 30 ... more details
Taxobox image Helix engaddenis.jpg image caption Helix engaddensis waking up after estivation . status NE www.iucnredlist.org . Downloaded on 23 February 2009. ref regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora br informal group Sigmurethra superfamilia Helicoidea familia Helicidae genus Helix gastropod Helix species H. engaddensis binomial Helix engaddensis binomial authority Bourguignat, J. R. 1852 Helix engaddensis is a species of snail common in the Levant , both in Mediterranean climate Mediterranean , desert climate desert and montane climates. It is smaller than the closely related European Garden snail and usually lighter in color. H. engaddensis goes through estivation . It is dormant in the ground during the dry season and emerges after the first rains in late autumn . Mating takes place soon after emerging. The snails are active through winter except in high montane regions, where they might be forced into a somewhat unnatural hibernation and return to an inactive state at the end of the wet season midspring . ref http www.archive.org stream malacologia181979inst malacologia181979inst djvu.txt ref References Reflist Category Helix Helicidae stub ... more details
Image Pi helix neg55 neg70 sideview.png thumb right 250px Side view of a standard helix of L alanine residues in atom ic detail. Two hydrogen bond s to the same peptide bond peptide group are highlighted ... point slightly downwards , i.e., towards the N terminus. A pi helix or helix is a type of secondary ... of a single amino acid into an helix . ref name pmid20888342 cite journal doi 10.1016 j.jmb.2010.09.034 ... Weaver TM year 2000 title The pi helix translates structure into function journal Protein science ... and amino acid propensities for the pi helix journal Protein Eng volume 15 issue 5 pages 353 358 ... helix are arranged in a right handed helix helical structure. Each amino acid corresponds to a 87 turn in the helix i.e., the helix has 4.1 residues per turn , and a translation of 1.15 ngstr m ... i 5 i hydrogen bonding defines a helix. Similar structures include the 310 helix 3 sub 10 sub helix i 3 i hydrogen bonding and the Alpha helixhelix i 4 i hydrogen bonding . Image Pi helix topview.png thumb left 150px Top view of the same helix shown above. Four carbonyl groups are pointing ... acid amino acid residues per turn of the helix. The majority of helices are only 7 residues in length ... residues in the helix are misleading. Some generalizations can be made, however. When the first ... sub helix is roughly 75 , whereas that for the helix is roughly 105 . Proline is often seen immediately ... polypeptide helix with trans isomers is given by the equation math 3 cos Omega 1 4 cos 2 left left phi psi right 2 right math Left handed structure In principle, a left handed version of the helix ... helix has roughly the same number of residues per turn 4.1 and helical pitch 1.5 angstroms or 150 ... are still made. A long left handed helix is unlikely to be observed in proteins because, among the naturally ... . See also alpha helix 3 10 helix secondary structure References reflist Protein secondary structure Category Protein structural motifs Category Helices protein stub de Helix es H lice pi ja ... more details
italic title Taxobox name Helix fossil range fossil range Oligocene Recent image Snail1web.jpg image caption Garden snail Helix aspersa on Limonium regnum Animal ia phylum Mollusca classis Gastropoda unranked ... genus Helix genus authority Carl Linnaeus Linnaeus , 1758 subdivision ranks Species subdivision See ... Schultes, accessed 1 April 2009. ref Helix is a genus of large air breathing land snails , Terrestrial ... around the Mediterranean Sea . Helix is the type genus of the family Helicidae . The best known species include Helix aspersa , the common, or brown garden snail, and Helix pomatia , the Roman snail, Burgundy snail, or edible snail. Helix pomatia H. pomatia and some other species are eaten as escargot s. Helix snails have been introduced throughout the world, where some, especially H. aspersa , have become garden pests. The genus Helix is known from the Oligocene on. ref Ivanov .... Species Subgenera and species within the genus Helix include today Subgenus HelixHelix albescens Rossmaessler, 1839 Helix lucorum Linnaeus , 1758 Helix pomatia Linnaeus , 1758 Burgundy Snail, Roman Snail, Edible Snail Helix philibinensis Rossm ssler, 1839 Subgenus Pelasga Helix pomacella Mousson, 1854 Helix figulina Rossm ssler, 1839 Subgenus Cornu Helix aspersa M ller, 1774 brown garden snail or common garden snail also known as Cantareus aspersus and Cornu aspersus Subgenus ? Helix aperta Born, 1778 Helix engaddensis Bourguinat, 1852 Levantine field snail Helix buchi Dubois de Montp reux, 1839 largest species of the genus Helix , a synonym ref Sysoev, A. & Schileyko, A. 2009. Land snails and slugs of Russia and adjacent countries. pp. 1 312, Fig. 1 142. Sofia. Pensoft . ref is Helix ... B.M. 2008. A new species of the genus Helix from the Lesser Caucasus sw Georgia . Journal of Conchology ... 39.php?id 20 20 20 20 20 20 20 20 20 20 20 20147 abstract ref . Helix godetiana ref Mylonas, M. 1996. Helix godetiana. In IUCN 2006. 2006 IUCN Red List of Threatened Species. www.iucnredlist.org . Downloaded ... more details
Helix is a pioneering database management system for the Apple Macintosh platform, created in 1983. Helix ... to construct sophisticated applications. While this sort of ease of use should have made Helix a killer ... problems relegated it to a niche product. As of 2005, Helix is twenty one years old, but still has ..., Helix s marketing and ownership problems led it to a life as a niche product on an OS with a small ..., Helix received rave reviews when it was released the next year. At the time the Mac only supported ..., with the OS and Helix on one floppy, and data on another. Leaving room for a maximum database size of under 500k, Helix s data management capabilities did not need to be all that strong. Nevertheless it was a full relational database . In May 1986 Odesta released Double Helix for 495. The main new ... applications. In comparison, the original Helix produced applications that were clearly running within Helix, much as a Microsoft Word document is clearly running inside Word . Released as a part of a larger suite of software, the Helix suite also included a stand alone run time system runtime version known as RunTime Helix which would allow users to run Double Helix applications without the full version installed, as well as MultiUser Helix which operated in a client server fashion. Upgrades to the Helix ... of time and money working on a version known as Remote Helix which ran the basic Helix development system ... Odesta split up, with the original Helix applications being spun off. Double Helix re emerged as Helix Express at Helix Technologies , marketed as a performance leader as opposed to easy to use . Unfortunately, the parent company became entangled in an unrelated but costly legal battle, and Helix languished. In 1998, Helix Technologies was purchased by The Chip Merchant, a San Diego based memory vendor, who released a major upgrade in 2000, adding TCP IP capabilities to Helix Client Server and improving ... and a slumping economy combined to drive The Chip Merchant into bankruptcy in 2002, sending Helix ... more details
italictitle Taxobox name Helix lutescens image Slimak lutescens.jpg image caption Four shells of Helix lutescens status NE regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Heterobranchia br clade Euthyneura br clade Panpulmonata br clade Eupulmonata br clade Stylommatophora br informal group Sigmurethra superfamilia Helicoidea familia Helicidae genus Helix gastropod Helix species H. lutescens binomial Helix lutescens binomial authority Carl Linnaeus Linnaeus , 1758 Helix lutescens is species of air breathing land snail , a Terrestrial animal terrestrial pulmonate gastropod mollusk in the family Helicidae , the true snails. This species of snail creates and uses calcareous love darts . Distribution Not listed in IUCN red list not evaluated NE ref 2006 IUCN Red List of Threatened Species. www.iucnredlist.org . Cited 2 April 2007. ref Its native distribution is peri carpathian . ref in Slovak Lisick M. J. 1991 Mollusca Slovenska The Slovak molluscs . VEDA vydavate stvo Slovenskej akad mie vied, Bratislava, 344 pp. ref List of non marine molluscs of Poland Poland Near Threatened NT, mentioned as lower risk LR ref http www.iop.krakow.pl pckz opis.asp?id 256&je pl Helix lutescens Polska Czerwona Ksi ga Zwierz t Bezkr gowce Bot generated title ref ref pl Polska Czerwona Ksi ga Zwierz t Bezkr gowce ref List of non marine molluscs of Slovakia Slovakia References reflist Category Helix Helicidae stub az Helix lutescens de Podolische Weinbergschnecke pl limak tawy ... more details
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