In mathematics, Reidemeister torsion or R torsion , or Reidemeister Franz torsion is a topological invariant ... to higher dimension s by harvtxt Franz 1935 and harvtxt de Rham 1936 . Analytic torsion or Ray Singer torsion is an invariant of Riemannian manifold s defined by harvs txt yes last1 Ray last2 Singer year1 1971 year2 1973a year3 1973b as an analytic analogue of Reidemeister torsion. harvs ... that Reidemeister torsion and analytic torsion are the same for compact Riemannian manifolds. Reidemeister torsion was the first invariant in algebraic topology that could distinguish between spaces ... topology as a distinct field. It can be used to classify lens space s. Reidemeister torsion is closely related to Whitehead torsion see harv Milnor 1966 . For later work on torsion see the books harv Turaev 2002 , harvs last Nicolaescu year1 2002 year2 2003 . Definition of analytic torsion If M is a Riemannian ... of the positive eigenvalues of the laplacian acting on i forms. The analytic torsion T M , E is defined ... of Reidemeister torsion Let X be a finite connected CW complex CW complex with fundamental group ... oplus n , even , D n math . We define the Reidemeister torsion math rho X U mathop det A in mathbf ... torsion math rho X U math is independent of the choice of the cellular basis for math ... torsion was first used to classify 3 dimensional lens space s in harv Reidemeister 1935 . The classification ... PNAS year 1977 volune 74 issue 7 pages 2651 2654 title Analytic Torsion and Reidemeister Torsion first ... Jeff title Analytic torsion and the heat equation journal Ann. Of Math. 2 volume 109 year 1979 issue ... first W. last Franz title Ueber die Torsion einer Ueberdeckung journal J. Reine Angew. Math. volume 173 year 1935 pages 245 254 citation last Milnor first J. title Whitehead torsion. journal Bull ... title Reidemeister torsion first A.S. last Mishchenko citation last M ller first Werner title Analytic torsion and R torsion of Riemannian manifolds. journal Adv. In Math. volume 28 year 1978 issue 3 ... more details
Other uses Torsion disambiguation Torsion field disambiguation Image Torsion along a geodesic.svg right thumb Torsion along a geodesic. In differential geometry , the notion of torsion is a manner of characterizing a twist or screw theory screw of a moving frame around a curve. The torsion of curves torsion of a curve , as it appears in the Frenet Serret formulas , for instance, quantifies the twist ... frame about the tangent vector. In the geometry of surfaces, the geodesic torsion describes how a surface ... connection that is, a connection vector bundle connection in the tangent bundle , torsion and curvature form the two fundamental invariants of the connection. In this context, torsion gives ... ed whereas curvature describes how the tangent spaces roll along the curve. Torsion may be described .... If is an affine connection on a differential manifold , then the torsion tensor is defined, in terms ... of vector fields . Torsion is particularly useful in the study of the geometry of geodesic s. Given ..., but differing by their torsions. There is a unique connection which absorbs the torsion , generalizing ... . Absorption of torsion also plays a fundamental role in the study of G structure s and Cartan s equivalence method . Torsion is also useful in the study of unparametrized families of geodesics, via ... of Einstein Cartan theory . The torsion tensor Let M be a manifold with a connection on the tangent bundle. The torsion tensor sometimes called the Cartan torsion tensor is a vector valued form ... are extended to vector fields away from the point thus it defines a tensor, much like the torsion . The Bianchi identities relate the curvature and torsion as follows. ref See Kobayashi Nomizu 1996 ... nabla XR Y,Z R T X,Y ,Z right 0 math Components of the torsion tensor The components of the torsion ... e sub i sub , e sub j sub . The components of the torsion are then math T k ij Gamma k ij Gamma k ji ... geodesic equations determine the symmetric part of the connection, the torsion tensor determines ... more details
unreferenced date January 2009 File Twisted bar.png thumbnail 120px right Torsion of a square section bar. In solid mechanics , torsion is the twisting of an object due to an applied torque , therefore is expressed in newton metre N m or foot pound force ft lbf . In sections perpendicular to the torque axis, the resultant shear stress in this section is perpendicular to the radius. For solid shafts of uniform circular cross section or hollow circular shafts with constant wall thickness, the torsion is math T frac J T r tau frac J T ell G phi math where math tau math is the maximum shear stress at the outer surface. J sub T sub is the torsion constant for the section. It is identical to the second moment of area J sub zz sub for concentric tube only. For other shapes J must be determined by other means. For solid shafts the membrane analogy is useful, and for thin walled tubes of arbitrary shape the shear flow approximation is fairly good, if the section is not re entrant. For thick walled tubes of arbitrary shape there is no simple solution, and finite element method finite element analysis FEA may be the best method. r is the distance between the rotational axis and the furthest point in the section at the outer surface . is the length of the object the torque is being applied to or over. is the angle of twist in radian s. G is the shear modulus or more commonly the modulus ... concentrations such as rough spots. Thus, shafts for use in high torsion are polished to a fine ... s circle . If the shaft is loaded only in torsion then one of the principal stresses will be in tension ... also Wiktionarypar torsion wikibooks Solid Mechanics Structural rigidity Torsion spring or bar Torsion ... Category Mechanics ar bs Torzija mehanika bg ca Torsi mec nica de Torsion Mechanik et V ne es Torsi n mec nica fa fr Torsion ko ia Torsion it Torsione he kk nl Wringspanning pl Skr canie simple Torsion mechanics sl Vzvoj sv Vridning ru ... more details
Multiple issues confusing June 2008 context June 2008 refimprove June 2008 The torsion constant is a geometrical property of a beam s cross section which is involved in the relationship between angle of twist and applied torque along the axis of the bar, for a homogeneous linear elastic bar. That is, the torsion constant describes a beam s torsional stiffness . History In 1820, the French engineer A. Duleau derived analytically that the torsion constant of a beam is identical to the second moment of area normal to the section J sub zz sub , which has an exact analytic equation, by assuming that a plane section before twisting remains plane after twisting, and a diameter remains a straight line. Unfortunately, that assumption is correct only in beams with circular cross sections, and is incorrect for any other shape. ref Archie Higdon et. al. Mechanics of Materials, 4th edition . ref For non circular cross sections, there are no exact analytical equations for finding the torsion constant. However approximate solutions have been found for many shapes. Non circular cross section always have warping deformations that require numerical methods to allow the exact calculation of the torsion constant. ref name David Advanced structural mechanics, 2nd Edition, David Johnson ref Partial Derivation For a beam of uniform cross section along its length math theta frac TL JG math where math theta math is the angle of twist in radians T is the applied torque L is the beam length J is the torsion constant also referred to as torsional stiffness G is the Modulus of rigidity shear modulus of the material ... radius b is the minor radius Square math J ,2.25 a 4 math ref name RoyMech7 Torsion Equations, Roy Beardmore, http www.roymech.co.uk Useful Tables Torsion Torsion.html ref where 2a is the side length ... the torsion constant using the finite element method. http www.mechatools.com en shapedesigner.html ... BXS Generator by http www.strand7.com Strand7 Pty Limited References references DEFAULTSORT Torsion ... more details
Infobox disease Name Torsion dystonia Image Caption DiseasesDB 29464 ICD10 ICD9 ICD9 333.6 ICDO OMIM 128100 MedlinePlus eMedicineSubj neuro eMedicineTopic 165 MeshID D004422 Torsion dystonia , also known as dystonia musculorum deformans , is a disease characterized by painful muscle contraction s resulting in uncontrollable distortions. This specific type of dystonia is found in children, with symptoms starting around the ages of 11 or 12. It commonly begins with contractions in one general area such as an arm or a leg that continue to progress throughout the rest of the body. It takes roughly 5 years for the symptoms to completely progress to a debilitating state. Causes The disease is caused by a genetic disorder which results in a defect in a protein called Torsin A . A mutation in the DYT1 gene causes the loss of an amino acid , glutamic acid, in the Torsin A protein. The defective protein creates a disruption in communication in neurons that control muscle movement and muscle control. This mutation is most usually inherited from a parent, but can occur sporadically. The disease is caused by a dominant allele , meaning that the person affected needs only one copy of the mutated DYT1 gene to have symptoms. However, only 30 to 40 percent of those that do have the gene actually have symptoms, leading researchers to believe that there are other factors involved. Classification There are several types of torsion dystonia that affect different areas of the body. However, it is unknown if the gene that causes Early Onset Torsion Dystonia is responsible for the other dystonias as well ... dystonia. Early onset torsion dystonia The most severe type of dystonia, it begins in an arm ... to a wheel chair. Treatment There is no cure for torsion dystonia. However, there are several medical ... of Torsion Dystonia is surgery. Surgery is performed only if the patient does not respond to the oral ... of torsion dystonia in the Ashkenazi Jewish population as stated by the Department of Epidemiology ... more details
if and only if the Whitehead torsion of the inclusion math M hookrightarrow W math vanishes ... 1. It is a well known conjecture that the Whitehead group of any torsion free group should vanish. The Whitehead torsion At first we define the Whitehead torsion math tau h in tilde K 1 R math for a chain ... torsion math tau f in Wh pi 1 Y math as follows. Let math tilde f tilde X to tilde Y math ... torsion for a chain homotopy equivalence and obtain an element in math tilde K 1 mathbf Z pi 1 Y math which we map to math Wh pi 1 Y math . This is the Whitehead torsion math tau f in Wh pi ... if the Whitehead torsion of the inclusion math M math math hookrightarrow math math W math vanishes ... M math whose Whitehead torsion is the considered element. The proofs use handle decomposition handlebody ... also Algebraic K theory Reidemeister torsion s Cobordism theorem References Bass, H., Heller, A. and Swan ..., Tokyo, 1977. Milnor, J. Whitehead torsion Bull. Amer. Math. Soc. 72 1966 358 426. Smale, S. On the structure ... torsion is in section two . Category Geometric topology Category Algebraic K theory Category Surgery ... more details
, or testiculartorsion. These are all conditions that should be investigated by a doctor some ...Unreferenced date April 2012 Testicular self examination is a recommended medical practice by which external feeling of the testicles can act as a first warning for testicular cancer. Testicular cancer is a significant killer of teenage boys and younger men roughly ages 15 35 or 40 , physician doctors recommend monthly self examination. Procedure and Diagnosis Men from puberty onwards should examine their testicle testes after a hot shower or bath, when the scrotum is looser ref name everyman cite web url http www.everyman campaign.org Testicular Cancer Testicular cancer self examination title Testicular Cancer Self Examination publisher The Institute of Cancer Research accessdate April 17, 2012 ref , and while standing. ref name nih cite web url http www.nlm.nih.gov medlineplus ency article 003909.htm title Testicular self examination publisher U.S. Department of Health and Human Services ... cause for worry and rarely is caused by testicular cancer when it does occur it may be later in the course ... slightly lower than the other Some symptoms of testicular cancer which is usually painless, however ... and life. Awareness and Aversion Testicular self examination has generally low rates of practice ... nursing cite journal url http journals.lww.com cancernursingonline Abstract 2005 07000 Testicular Cancer and Testicular Self examination .3.aspx title Testicular Cancer and Testicular Self examination ... 5069.2002.00251.x abstract title Testicular Self Examination in Young Adult Men author Wynd, Christine ... Channel 4 How To Check Your Testicles video http www.everyman campaign.org Testicular Cancer Testicular ... checkemlads.com Testicular cancer support and awareness, run by survivors http kidshealth.org teen ... Testicular cancer support Category Male genital procedures human repro stub cs Samovy et en varlat es Autoexploraci n testicular ... more details
Testicular sperm extraction TESE is the process of removing a small portion of tissue from the testicle under local anesthesia and extracting the few viable Spermatozoon sperm cell s present in that tissue for the purpose of intracytoplasmic sperm injection ICSI . ref cite book last D.Graham first Sam coauthors James Francis Glenn, Thomas E. Keane title Glenn s urologic surgery publisher Lippincott Williams & Wilkins date 2004 pages 472 482 url http books.google.co.uk books?id AeZJK Pj4xkC&pg PA472&dq Testicular sperm extraction&as brr 3&client firefox a v onepage&q Testicular 20sperm 20extraction&f false isbn 9780781740821 ref The testicular sperm extraction process is recommended to men who are unable to produce sperm by ejaculation as a result azoospermia , such as caused by primary testicular failure, congenital absence of the vas deferens or non reconstructed vasectomy . Intracytoplasmic sperm injection ICSI and testicular sperm extraction TESE have reduced the need for donor sperm. Serum inhibin B weakly indicates presence of sperm cells in the testes, raising chances for successfully achieving pregnancy through TESE, although the association is not very substantial, having a sensitivity of 0.65 95 confidence interval CI 0.56 0.74 and a specificity of 0.83 CI 0.64 0.93 for prediction the presence of sperm in the testes in non obstructive azoospermia. ref cite doi 10.1093 humupd dmq024 ref See also Azoospermia References Reflist Category Fertility medicine human repro stub ... more details
Image Haller torsion pendulum anniversary clock.jpg thumb Anniversary clock made by S. Haller & Sohne Co. A torsion pendulum clock , or torsion clock , is a mechanical clock which keeps time with a mechanism called a Torsion spring torsion pendulum . This is a weighted disk or wheel, often a decorative wheel with 3 or 4 chrome balls on ornate spokes, suspended by a thin wire or ribbon called a torsion spring . The torsion pendulum rotates about the vertical axis of the wire, twisting it, instead of swinging like an ordinary pendulum . The force of the twisting torsion spring reverses the direction of rotation, so the torsion pendulum oscillates slowly, clockwise and counterclockwise. The clock s gears apply a pulse of torque to the top of the torsion spring each rotation to keep the wheel going. The wheel and torsion spring function similarly to a watch s balance wheel and Balance spring hairspring , as a harmonic oscillator to control the rate of the clock s hands. Description Torsion ... mechanism is exposed under a glass case or dome, to allow people to watch the torsion pendulum turn ..., because many of them only have to be wound once a year. Mechanism Torsion clocks are capable of running much longer between windings than clocks with an ordinary pendulum, because the torsion pendulum ... not as accurate as clocks with ordinary pendulums. One reason is that the oscillation period of the torsion .... The rate of the clock can be made faster or slower by an adjustment screw mechanism on the torsion ... the moment of inertia of the torsion pendulum and the faster it will turn, like a spinning ice skater who pulls in her arms. This causes the clock to speed up. One oscillation of the torsion ... title Horolovar Springs Hooks Law mailinglist 400 Day, Atmos and other Torsion Clocks, NAWCC date ... to pulses to drive the torsion pendulum, works rather like an anchor escapement . A crutch device at the top of the torsion spring engages a lever with two anchor shaped arms the arms in turn alternately ... more details
with both penile and testicular agenesis and is known by the slang term nullo . This combination of both ... independently after full testicular development in this case its cause is unknown. Treatment A problem ... testes are of otherwise normal male appearance. Males with testicular agenesis tend not to produce the reproductive ... muscular development is retarded and testicular agenetics are of rather frail build with short limbs ... or testicular agenesis, but not both, usually continue as males throughout their lives. Historically, people with both penile and testicular agenesis were raised as females and eventually underwent ... more details
multiple image align right direction horizontal image1 AUawise.png width1 150 caption1 A typical torsion siege engine image2 Roman Onager.jpg width2 250 caption2 Sketch of an onager siege weapon onager , a type of torsion siege engine A torsion siege engine , or simply a torsion engine , is a kind of catapult and a siege engine , which uses torsion mechanics torsion power to propel the projectiles . Some examples of torsion siege engines are the onager siege weapon onager and the ballista . The first torsion siege engines were developed by the ancient Greece ancient Greeks ref cite web url http en.wikipedia.org wiki Siege engine Ancient siege engines title Ancient siege engines publisher English Wikipedia accessdate 2009 01 13 ref . Later on, they were partially replaced by the trebuchet in the Middle Ages then all catapults were gradually replaced by the cannon in the 14th century ref cite web url http en.wikipedia.org wiki Catapult Medieval catapults title Medieval catapults publisher English Wikipedia accessdate 2009 01 13 ref . Notes reflist spacing artillery stub Ancient mechanical artillery and hand held missile weapons Category Ancient artillery it Macchine d assedio a torsione ... more details
Image Torsion Bar no load.jpg right thumb 250px A torsion bar with no load applied. Image Torsion Bar with load.jpg right thumb 250px A torsion bar with a load applied. image Front axle section torsion bar 2.jpg thumb 250px A front VW Beetle suspension cross section A torsion bar suspension , also known as a torsion spring suspension or torsion beam suspension , is a general term for any vehicle suspension vehicle suspension that uses a torsion bar as its main weight bearing spring. One end of a long metal bar is attached firmly to the vehicle chassis the opposite end terminates in a lever, the torsion ... s Torsion mechanics torsion resistance. The effective spring rate of the bar is determined by its length, cross section, shape and material. Usage Torsion bar suspensions are used on combat vehicles ... and Toyota . Manufacturers change the torsion bar or key to adjust the ride height, usually to compensate ... bolts on the stock torsion key, rotating the stock key too far can bend the adjusting bolt and more importantly place the shock piston outside its standard travel. Over rotating the torsion bars ... forged metal torsion key kits use relocked adjuster keys to prevent over rotation, and shock brackets to keep the piston travel in the stock range. Advantages and disadvantages The main advantages of a torsion ... s. A disadvantage is that torsion bars, unlike coil springs, usually cannot provide a progressive spring rate. In most torsion bar systems, ride height and therefore many handling features may be changed by simply adjusting bolts that connect the torsion bars to the steering knuckle s. In most cars with this type of suspension, swapping torsion bars for a different spring rate is usually an easy task. Leveling Some vehicles use torsion bars to provide self levelling suspension automatic levelling ... front torsion bar suspension and a flexible trailing dead axle, also sprung by torsion bars. The flexibility ... Torsion Bars Support Car Without Springs Popular Mechanics , October 1934 drawings explaining Citroen ... more details
A torsion beam suspension is a vehicle suspension vehicle suspension similar to a trailing arm suspension but where both trailing arms are connected by a beam. In contrast to a torsion bar suspension , the main weight bearing springs are usually coil springs, either mounted over the shock absorber s or independently from them. Obviating anti roll bar s, the central torsion beam allows for a limited degree of freedom of each wheel when forced. image Torsion beam 1.jpg thumb 220px Torsion beam rear suspension of VW Golf Mk3 This semi independent suspension has been used for decades by the great majority of compact European and Japanese front wheel drive cars up to VW Golf Golf size. It is cheap to design and manufacture, compact with little boot space intrusion, and although ride and handling are theoretically inferior to more sophisticated designs, it has been used even in the sportier Volkswagen Golf GTI. image Torsion beam 2.jpg thumb left 220px Torsion beam rear suspension of VW Golf Mk3 External links http www.autozine.org technical school suspension tech suspension21.htm Trailing Category Automotive suspension technologies ... more details
PBB geneid 7182 Testicular receptor 4 also known as NR2C2 nuclear receptor subfamily 2, group C, member 2 is a protein that in humans is encoded by the NR2C2 gene . ref name entrez cite web title Entrez Gene NR2C2 url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 7182 accessdate ref ref name pmid8016112 cite journal author Chang C, Da Silva SL, Ideta R, Lee Y, Yeh S, Burbach JP title Human and rat TR4 orphan receptors specify a subclass of the steroid receptor superfamily journal Proc. Natl. Acad. Sci. U.S.A. volume 91 issue 13 pages 6040 4 year 1994 month June pmid 8016112 pmc 44133 doi 10.1073 pnas.91.13.6040 url issn ref ref name pmid8661150 cite journal author Yoshikawa T, DuPont BR, Leach RJ, Detera Wadleigh SD title New variants of the human and rat nuclear hormone receptor, TR4 expression and chromosomal localization of the human gene journal Genomics volume 35 issue 2 pages 361 6 year 1996 month July pmid 8661150 doi 10.1006 geno.1996.0368 url issn ref The testicular receptor 4 is a member of the nuclear receptor family of transcription factor s. Interactions Testicular receptor 4 has been shown to Protein protein interaction interact with Androgen receptor , ref name pmid10611280 cite journal author Lee YF, Shyr CR, Thin TH, Lin WJ, Chang C title Convergence of two repressors through heterodimer formation of androgen receptor and testicular orphan receptor 4 a unique signaling pathway in the steroid receptor superfamily journal Proc. Natl. Acad. Sci. U.S.A. volume 96 issue 26 pages 14724 9 year 1999 month December pmid 10611280 pmc 24715 ... doi 10.1074 jbc.M205944200 url issn ref See also Testicular receptor References reflist Further reading ... heterodimer formation of androgen receptor and testicular orphan receptor 4 a unique signaling pathway ... cite journal author Yang Y, Wang X, Dong T, et al. title Identification of a novel testicular orphan ... no update citations no es Receptor testicular 4 ... more details
In algebraic geometry Mazur s torsion theorem , due to Barry Mazur , classifies the possible torsion subgroup s of the group of rational points on an elliptic curve defined over the rational numbers. If C sub n sub denotes the cyclic group of order n , then the possible torsion subgroups are C sub n sub with 1 n 10, and also C sub 12 sub and the Direct sum of groups direct sum of C sub 2 sub with C sub 2 sub , C sub 4 sub , C sub 6 sub or C sub 8 sub . References Mazur, Barry Rational isogenies of prime degree , Inventiones Math. 44, 2 June 1978 , pp 129 162. Category Theorems in number theory Category Diophantine geometry Category Algebraic curves Category Theorems in algebraic geometry algebra stub es Teorema de torsi n de Mazur ... more details
PBB geneid 7181 The testicular receptor 2 TR2 also known as NR2C1 nuclear receptor subfamily 2, group C, member 1 is protein that in humans is encoded by the NR2C1 gene . ref name entrez cite web title Entrez Gene NR2C1 nuclear receptor subfamily 2, group C, member 1 url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 7181 accessdate ref ref name pmid2597158 cite journal author Chang C, Kokontis J, Acakpo Satchivi L, Liao S, Takeda H, Chang Y title Molecular cloning of new human TR2 receptors a class of steroid receptor with multiple ligand binding domains journal Biochem. Biophys. Res. Commun. volume 165 issue 2 pages 735 41 year 1989 month December pmid 2597158 doi 10.1016 S0006 291X 89 80028 2 url ref TR2 is a member of the nuclear receptor family of transcription factor s. Interactions Testicular receptor 2 has been shown to Protein protein interaction interact with Androgen receptor , ref name pmid12949936 cite journal author Mu X, Chang C title TR2 orphan receptor functions as negative modulator for androgen receptor in prostate cancer cells PC 3 journal Prostate volume 57 issue 2 pages 129 33 year 2003 month October pmid 12949936 doi 10.1002 pros.10282 url ref Estrogen receptor alpha , ref name pmid12093804 cite journal author Hu YC, Shyr CR, Che W, Mu XM, Kim E, Chang C title Suppression of estrogen receptor mediated transcription and cell growth by interaction with TR2 orphan receptor journal J. Biol. Chem. volume 277 issue 37 pages 33571 9 year 2002 month September pmid 12093804 doi 10.1074 jbc.M203531200 url ref HDAC3 , ref name pmid14521922 cite journal author Li G, Franco PJ, Wei LN title Identification of histone deacetylase 3 domains that interact with the orphan nuclear receptor TR2 journal Biochem. Biophys. Res. Commun. volume ... me.15.8.1318 url ref and HDAC4 . ref name pmid12943985 ref name pmid11463856 See also Testicular ... manual inspection no update protein box yes update summary no update citations no es Receptor testicular ... more details
For other notions of torsionTorsion field disambiguation Torsion field Torsion disambiguation Torsion ... J. Sarfatti , R. N. Boyd, Richard C. Hoagland A torsion field also called axion field , spin field ... for torsion field research from the Ministry of Science from 1992 to 1995 and from the Ministry of Defense ... containing it. The word torsion refers to any variable that describes rotation. Thus, torsion ... or the stress tensor of a solid body under torsion stress can be described as torsion fields, although ... spin field or torsion field theories claim that Angular momentum coupling spin spin interaction ... Torsion fields of Earth and Universe journal Earth and Universe year 1996 volume 6 pages 9 17 ref ... 02 11 in Russian br English title Cite journal last Byalko first A. V. title Torsion Myths journal Priroda issue 9 pages 93 102 volume 1998 url http www.skeptik.net pseudo torsion1.htm ref , torsion .... Citation needed date September 2010 The harnessing of torsion fields has been claimed to make everything ... WMDs . ref http www.enterprisemission.com Norway Message.htm A Nobel Torsion Message Over Norway ..., ref http www.patentstorm.us patents 6548752 description.html System and method for generating a torsion field US Patent 6548752 ref manufactured and sold. Torsion field theories are sometimes presented ... theories of gravitation for the Poincar and the affine groups, which seek to add torsion of space ... pseudo rubakov.htm in Russian ref It may be shown that space time curvature and torsion are alternative .... I. coauthors Pereira, J. G. title Torsion Gravity A Reappraisal journal Int. J. Mod. Phys. D volume ... bibcode 2004IJMPD..13.2193A ref Torsion field related scams Proponents of torsion field theories have ... it to a torsion field generator. The group applied to the government of the Russian Federation for funding ... did a report on torsion fields, on Einsten Cartan fields, on the real thing. That was real science ... url http www.guseynov.lv E P Kruglyakov 2.pdf DEFAULTSORT Torsion Field Category Pseudophysics es ... more details
A torsion bar antenna or TOBA is a novel scheme for a gravitational wave detector , proposed by M. Ando, et. al in 2010. The proposed design is composed of two, long, thin bars, suspended as torsion pendula in a cross like fashion. Their differential angle sensitive to tidal gravitational wave forces would be compared using a set of optical cavities with one end mirror of each cavity fixed two the ends of the each bar. Such a detector could be fashioned either for ground based or space based use. The predicted frequency band over which such a detector would be most sensitive band would be centered around 1 Hz, similar to DECIGO . This frequency range would complement current ground based, laser interferometric detectors whose sensitive band is between 10 100 Hz and several kHz, such as LIGO or Virgo interferometer Virgo , and proposed space based, laser interferometric detectors such as Laser Interferometer Space Antenna LISA whose sensitive band is centered around 10 sup 4 sup Hz . ref cite journal first M. last Ando, et. al title Torsion bar antenna for low frequency gravitational wave observations. journal Phys. Rev. Lett. volume 105 number 161101 month October year 2010 doi 10.1103 PhysRevLett.105.161101 bibcode 2010PhRvL.105p1101A ref References references Gravitational wave observatories Category Gravitational wave telescopes ... more details
class of the type of a non identity element is a well defined invariant of a torsion free abelian group of rank 1. We call this invariant the type of a torsion free abelian group of rank 1. If two torsion free abelian groups of rank 1 have the same type they may be shown to be isomorphic. Hence there is a bijection between types of torsion free abelian groups of rank 1 and their isomorphism ... more details
Infobox Anatomy Name Appendix of testis Latin appendix testis GraySubject 258 GrayPage 1242 Image Gray1148.png Caption The right testis , exposed by laying open the tunica vaginalis . Image2 Caption2 System Artery Vein Nerve Lymph Precursor M llerian duct MeshName MeshNumber DorlandsPre a 54 DorlandsSuf 12147714 The appendix testis or hydatid of Morgagni is a vestigial remnant of the M llerian duct , present on the upper pole of the testis and attached to the tunica vaginalis . It is present about 90 of the time. Clinical significance Although it has no physiological function, it can be medically significant in that it can, rarely, undergo Testicular torsion torsion i.e. become twisted , causing acute one sided testicular pain and may require surgical excision to achieve relief. 1 3 of patients present with a palpable blue dot discoloration on the scrotum. This is nearly diagnostic of this condition. Although if clinical suspicion is high for testicular torsion, a surgical exploration of the scrotum is warranted. Occasionally a torsion of the hydatid of Morgagni can produce symptoms mimicking those created by a testicular torsion a torsion of the hydatid, however, does not lead to any impairment of testicular function. External links eMedicine emerg 595 GPnotebook 1281753080 WhoNamedIt synd 292 Male reproductive system Category Male reproductive system genitourinary stub es Hid tide de Morgagni it Idatide di Morgagni sv Appendix testis ... more details
Image Illu testis surface.jpg thumb 1 Epididymis BR 2 Head of epididymis BR 3 Lobules of epididymis BR 4 Body of epididymis BR 5 Tail of epididymis BR 6 Duct of epididymis BR 7 Deferent duct ductus deferens or vas deferens Prehn s sign is a medical diagnostic indicator that was once believed to help determine whether the presenting testicular pain is caused by acute epididymitis or from testicular torsion . ref name urlDiagnosis and Treatment of the Acute Scrotum February 15, 1999 American Academy of Family Physicians Cite web url http www.aafp.org afp 990215ap 817.html title Diagnosis and Treatment of the Acute Scrotum February 15, 1999 American Academy of Family Physicians work accessdate ref Although elevation of the scrotum when differentiating epididymitis from testicular torsion is of clinical value, Prehn s sign has been shown to be inferior to Doppler ultrasound to rule out testicular torsion. ref Cite journal author Lavallee ME, Cash J title Testicular torsion evaluation and management journal Curr Sports Med Rep volume 4 issue 2 pages 102 4 year 2005 month April pmid 15763047 doi url ref According to Prehn s sign, the physical lifting of the testicles relieves the pain of epididymitis but not pain caused by testicular torsion. ref name urlCase Based Pediatrics Chapter Cite web url http www.hawaii.edu medicine pediatrics pedtext s13c10.html title Case Based Pediatrics Chapter work accessdate 2008 10 18 ref Negative Prehn s sign indicates no pain relief with lifting the affected testicle, which points towards testicular torsion which is a surgical emergency and must be relieved within 6 hours. Positive Prehn s sign indicates there is pain relief with lifting the affected testicle, which points towards epididymitis. References Reflist Eponymous medical signs for reproductive system Category Medical signs Med sign stub cs Prehnovo znamen de Prehn Zeichen fr Signe de Prehn pl Objaw Prehna ... more details
Unreferenced stub auto yes date December 2009 Orphan date December 2009 Vanishing testis refers to the disappearance of one or other testis during embryo nic or foetus foetal development. It is one of the causes of monorchism , and is thought to be due to intrauterine testicular torsion . DEFAULTSORT Vanishing Testis Disease stub Category Congenital disorders of male genital organs ... more details
lead to a misdiagnosis of cryptorchidism . The cremasteric reflex may be absent with testiculartorsion ... can be helpful in recognizing testicular emergencies. The presence of the cremasteric reflex does not eliminate testiculartorsion from a differential diagnosis, but it does broaden the possibilities to include epididymitis or acute scrotum other causes of scrotal and testicular pain. In any event, if testiculartorsion cannot be definitively eliminated in an expeditious manner, a testicular Medical ... more details
Surgical emergency is a medical emergency which requires immediate surgery surgical intervention the only way to solve the problem successfully . The following conditions are surgical emergencies Acute Physical trauma trauma Accidental amputation Acute appendicitis Ruptured aortic aneurysm Aortic dissection Bleeding ectopic pregnancy Bowel obstruction Internal bleeding Gastrointestinal perforation Intestinal volvulus Cardiac tamponade Acute subdural hematoma Acute airway obstruction Limb ischemia Acute mesenteric ischemia Pneumothorax Paraphimosis Peritonitis Retinal detachment Priapism Retained abortion Stercoral perforation Testicular torsion Urinary retention See also List of medical emergencies Advanced Trauma Life Support References Monson JRT, Duthie G, O Malley K Eds. . Surgical Emergencies . Blackwell Science UK , 1999. ISBN 0 632 05047 0 Category Emergency medicine med stub ... more details
to torque torsion , in which the testicle rotates within its sac and kinks off its own blood supply. Testiculartorsion may result in irreversible damage to the testicle within hours. The contents ... , testicular artery , cremasteric artery 3 fascial layers external spermatic, cremasteric, and internal spermatic fascia 3 other structures pampiniform plexus, vas deferens ductus deferens , testicular ... more details
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