Infobox disease Name Testiculartorsion Image Illu testis surface.jpg Caption DiseasesDB 12984 ICD10 ... D013086 Testiculartorsion is when the spermatic cord to a testicle twists, cutting off the blood supply. The most common symptom is acute testicular pain and the most common underlying cause is a congenital ... and treatment is required in order to save the viability of the testicle. Signs and symptoms Testiculartorsion usually presents with an acute onset of diffuse testicular pain and tenderness of less ... of testiculartorsion are similar to the infection epididymitis . Risk factors Congenital Conditions that allow the testicle to rotate predispose to torsion. ref name PC2010 A congenital malformation ... the abrupt temperature change can trap the testicle in that position. The result is a testiculartorsion ... for torsion is indicated when the onset of testicular pain is sudden and or severe. In general a doppler ultrasound should be obtained only in low suspicion cases to rule out torsion while in those ... found to be reliable in distinguishing torsion from other causes of testicular pain such as epididymitis . ref Cite journal author Lavallee ME, Cash J title Testiculartorsion evaluation and management .... ref http emedicine.medscape.com article 778086 treatment ref Testiculartorsion is a surgical ... journal author Ringdahl E, Teague L title Testiculartorsion journal Am Fam Physician volume 74 issue ... Male diseases of the pelvis and genitals DEFAULTSORT TesticularTorsion Category Medical emergencies Category Diseases of male genital organs de Hodentorsion es Torsi n testicular fr Torsion testiculaire ... the risk of torsion. ref name PC2010 Temperature Torsions are sometimes called winter syndrome . This is because ... doi url ref In cases of true torsion the cremasteric reflex is typically absent, the scrotum is generally ... doppler ultrasound scan of the scrotum is nearly 100 accurate at detecting torsion. ref ... diagnosis of acute spermatic cord torsion. Rotation of the cord a key to the diagnosis. journal ... more details
wiktionary The word torsion may refer to the following In geometry Torsion of a curve Torsion tensor in differential geometry The closely related concepts of Reidemeister torsion also called R torsion, Franz torsion, de Rham torsion and analytic torsion also called Ray Singer torsion Whitehead torsion In algebra Torsion algebra Tor functor In medicine Ovarian torsionTesticulartorsion Spiral fracture , a.k.a. Torsion fracture Bloat particularly in cattle and dogs Horse colic Torsion In physics and engineering Torsion mechanics Torsion coefficient Torsion pendulum Torsion spring or bar Torsion field pseudoscience , a theory by Russian scientists In biology Torsion gastropod , a developmental feature of all gastropods mathdab bs Torzija vor cs Torze de Torsion es Torsi n desambiguaci n fr Torsion homonymie it Torsione disambigua pt Tor o ru simple TorsionTorsion Problem ... more details
Infobox disease Name Testicular disease Image Caption DiseasesDB ICD10 ICD10 E 29 e 20 , ICD10 N 43 n 40 ICD10 N 44 n 40 ICD9 ICD9 257 , ICD9 603 ICD9 604 ICDO OMIM MedlinePlus eMedicineSubj eMedicineTopic MeshID D013733 Testicular diseases can be classified as endocrine disorder s or as a disorders of the reproductive system . The testicles are well known to be very sensitive to groin attack impact and injury . Blue balls is a slang term for a temporary fluid congestion in the testicles and prostate region caused by prolonged sexual arousal . The most prominent diseases of testicles are testicular cancer and other neoplasms swelling of a testicle, caused by hydrocele testis inflammation of the testicles, called orchitis inflammation of the epididymis, called epididymitis retention cyst of a tubule of the rete testis or the head of the epididymis , called spermatocele spermatic cord torsion also called testiculartorsion varicocele &mdash swollen vein from the testes, usually affecting the left testicle ref http kidshealth.org teen sexual health guys varicocele.html Varicocele Bot generated title ref Hydrocele testis Collection of fluid around the testicle, like a water balloon. Completely harmless. anorchidism is the absence of one or both testicles. The removal of one or both testicles is termed Inguinal orchiectomy , in medicine where orchiectomy and orchectomy are synonymous , and castration in general use, especially when done as punishment or torture, or as a catch all term for orchidectomy in a veterinary context. Gelding in the specifically equine sense. Testicular prostheses are available to mimic the appearance and feel of one or both testicles, when absent as from injury or as treatment for gender identity disorder . There have also been some instances of their implanting in dogs ref http www.neuticles.com Neuticles ref Other testicular issues Cryptorchidism or undescended testicles , when the testicle does not descend into the scrotum of the infant boy. References ... more details
Unreferenced date November 2006 Orphan date February 2009 A testicular nubbin is the residual tissue of the human testis after a supposed perinatal Blood vessel vascular accident involving the testicular blood supply. It was originally discovered on patient Joseph Newman. This was first case of a nubbin being found on a human s head and there has never been any documentation of anyone since, with the same condition. It is so rare that some have said he should in fact, be kept in solitude, so that this highly disgusting facial feature could never be passed on. The blood supply of the testis twists called torsion thereby cutting off the blood supply to the testis and results in testicular atrophy shrinking . The nubbin is usually identified in childhood by the absence of a palpable testis in the scrotal sac . The tissue remnant usually includes fibrous tissue and signs of old infarction with hemosiderin deposition identified histologically. The controversy involves whether these should be removed and whether there is a risk of future malignancy. These are typically removed surgically by pediatric urologists or pediatric general surgeons through either a scrotal or ingiunal or both incision. DEFAULTSORT Testicular Nubbin Category Male reproductive system ... more details
Infobox Disease Name PAGENAME Image Caption DiseasesDB ICD10 ICD9 ICDO OMIM MedlinePlus eMedicineSubj med eMedicineTopic 2859 eMedicine mult eMedicine2 radio 682 MeshID Testicular trauma is an injury to one or both testicle s. Types of injuries include blunt, penetrating and degloving. Because the testes are located within the scrotum , which hangs outside of the body, they do not have the protection of muscles and bones. This makes it easier for the testes to be struck, hit, kicked or crushed, which occurs most often during contact sport s. fact date February 2010 Males can protect their testicles by wearing Protective cup Protective cup athletic cups during sports. Trauma to the testes can cause severe pain, bruising, and or swelling. In most cases, the testes which are made of a spongy material can absorb the shock of an injury without serious damage. A rare type of testicular trauma, called testicular rupture , occurs when the testicle receives a direct blow or is squeezed against the hard bones of the pelvis. This injury can cause blood to leak into the scrotum. In severe cases, surgery to repair the rupture and thus save the testicle may be necessary. See also Groin attack Testicular torsion disease stub Category Urology ... more details
diagnosis of testicular pain is broad and involves conditions from benign to life threatening. The most common causes of pain in children presenting to the emergency room are testiculartorsion 16 , torsion of a testicular appendage 46 , and epididymitis 35 . ref cite journal author ... month February pmid 7738751 doi url ref In adults the most common cause is epididymitis. TesticulartorsionTesticulartorsion usually presents with an acute onset of diffuse testicular pain and tenderness ... thigh is typically present in epididymitis but absent in testiculartorsion as the testis is already ... exam finding has not been found to be reliable in distinguishing torsion from other causes of testicular pain such as epididymitis . ref cite journal author Lavallee ME, Cash J title Testiculartorsion ... include a urinalysis usually normal in testiculartorsion . Pyuria and bacteriuria white ... Testicular pain or scrotal pain has a number of different causes. These rank from benign muscular skeletal problems to Emergency medicine emergent condition such as Fournier s gangrene and testiculartorsion . The diagnostic approach involves making sure no serious conditions are present and may ... definitive management depends on the underlying cause of the pain. Definition Testicular pain is when ... , and orchitis , as well as varicocele , hydrocele , spermatocele , polyarteritis nodosa , testiculartorsion , previous surgery and trauma. ref name PC2010 In 25 of cases the cause is never determined ... 25 years of age ref name PC2010 cite journal author Wampler SM, Llanes M title Common scrotal and testicular ... Many other less common conditions can lead to testicular pain. These include inguinal hernia s, injury, hydrocele s, and varicocele s among others. Testicular cancer is usually painless. ref cite ... of torsion is certain imaging should not delay definitive management such as physical maneuvers and surgery ... more details
Infobox disease Name Testicular microlithiasis Image Alt Caption DiseasesDB ICD10 ICD9 ICDO OMIM 610441 MedlinePlus eMedicineSubj eMedicineTopic MeshID GeneReviewsID GeneReviewsName Testicular microlithiasis is an unusual condition diagnosed on testicular ultrasound. It is found in between 1.5 to 5 of normal ..., non progressive disease. The cause is unknown, but this condition has been associated with testicular ... germ cell neoplasia. Classic testicular microlithiasis is defined as five or more echogenic foci per view in either or both testes, and limited testicular microlithiasis defined as one or more echogenic foci that do not satisfy the criteria for classic testicular microlithiasis. In 80 of cases, both testicles are affected. Testicular microlithiasis is not associated with risk of testicular cancer in asymptomatic individuals with no risk factors for testicular germ cell tumor. However, a large meta analysis has shown that in individuals with associated risk factors for testicular germ cell tumor , the increase in risk of concurrent diagnosis of testicular germ cell tumor, or testicular carcinoma ... Ang, KK, Ching, BC, Mohan, C, Toh, CK, Tan, MH title Testicular microlithiasis predicts concurrent testicular germ cell tumors and intratubular germ cell neoplasia of unclassified type in adults ... 32 pmid 20578177 ref . There is extensive controversy over whether testicular microlithiasis in individuals with testicular germ cell tumor, or risk factors for such, should undergo testicular biopsy to exclude the presence of testicular carcinoma in situ, also known as intratubular germ cell neoplasia of unclassified type. Additionally, whether the presence of testicular microlithiasis should influence decision for adjuvant chemotherapy or surveillance in individuals with testicular germ cell ... ref cite web url http www.nature.com nrurol journal v8 n3 full nrurol.2011.1.html title Testicular ... . There is no cure or treatment for testicular microlithiasis, however, patients may be monitored via ... more details
unsourced date September 2008 Testicular rupture also called fractured testis is a rip or tear in the tunica albuginea resulting in extrusion of the testicle testicular contents. It is a rare complication of testicular trauma . It may cause pain, scrotal swelling, nausea and vomiting sometimes . Treatment consists of Exploratory surgery surgical exploration with repair of the defect. External links http rad.usuhs.mil medpix topic display.html?recnum 4560 MedPix Testicular rupture Category Urology disease stub ... more details
8871921 issue 8 ref . In rat experiments, testiculartorsion leads to neutrophil entry into the testis ... 1 in the mammalian testis and their involvement in testiculartorsion and autoimmune orchitis ... pmid 1500475 issue 6 ref TesticulartorsionTesticulartorsion is a condition of physical twisting ... E, Teague L. title Testiculartorsion. journal Am Fam Physician. volume 74 pages 1739 1743 year 2006 ...Testicular Immunology is the study of the immune system within the testis . It includes an investigation of the effects of infection , inflammation and immune factors on testicular function. Two unique characteristics of testicular immunology are evident 1 the testis is described as an immunologically ... instead of promoting inflammation. History of testicular immunology 460 377 BC Hippocrates described testicular inflammation associated with mumps ref name HedgerBook cite book author Hedger MP ... presenting cells which activate lymphocytes . Testicular macrophages are the largest population ... FA title Porcine reproductive and respiratory syndrome virus replicates in testicular germ cells .... In the rat, testicular macrophages have been described as either resident or newly arrived from the blood .... volume 59 pages 371 378 year 1998 pmid 9687310 doi 10.1095 biolreprod59.2.371 issue 2 ref . Testicular ... of the inflammatory cytokines TNF and Interleukin 1 IL 1 by activated rat testicular macrophages ... DJ, Atkins RC, Hedger MP title Secretion of bioactive interleukin 1 by rat testicular macrophages in vitro ... to infectious stimuli, testicular macrophages are also involved in maintaining normal testis ... JC title Testosterone regulates 25 hydroxycholesterol production in testicular macrophages. journal ... Rooijen N. title Requirement for testicular macrophages in Leydig cell proliferation and differentiation ..., Garc a M, van Rooijen N, Aguilar E title In vivo manipulation depletion versus activation of testicular ... of testicular macrophages in the rat. journal J Endocrinol. volume 136 pages 407 413 year 1993 ... more details
unreferenced date November 2009 Testicular atrophy is a medical condition in which the male reproductive organ anatomy organ s the testes , which in humans are located in the scrotum diminish in size and may be accompanied by loss of function. This does not refer to temporary changes, such as those brought on by cold. Some medications can cause testicular atrophy. Anabolic Androgenic Steroids AAS can cause testicular atrophy by reducing the amount of luteinizing hormone LH produced by the pituitary gland. LH stimulates the testicles to produce testosterone. Testicular atrophy caused by steroid use can be prevented by taking hCG, a drug which mimics the effect of LH. However, hCG will simply address the symptoms. Endogenious levels of anabolic androgenic steroids will remain the cause, and testicular atrophy will continue until the male body regains homeostasis. It is unclear how long hCG can be administered to a male on anabolic androgenic steroids before desensitization occurs. See also Orchitis References reflist External links http www.tabexperts.com TesticularAtrophy.htm Following Inguinal Hernia repair med sign stub Category Male reproductive system de Hodenatrophie pt Atrofia testicular ... more details
findings in testicular sarcoidosis simulating malignant nodule. J Clin Ultrasound 1999 27 81 3 PubMed ... disease. The peak incidence of sarcoidosis and testicular neoplasia coincide at 20 40 years and this is why most patients end up having an orchiectomy. However, testicular tumours are much more common in white men, less than 3.5 of all testicular tumours being found in black men. ref Daniels JL Jr, Stutzman RE, McLeod DG. A comparison of testicular tumors in black and white patients. J Urol 1981 ... in patients with bilateral testicular disease . References Reflist External links Photos http www.gfmer.ch ... more details
gives one or two twigs to the Cremaster . Additional images gallery Image Testicular artery bull .jpg Testicular artery of a bull steer . Image Gray585.png The veins of the right half of the male pelvis ... testis. gallery See also testicular vein ovarian vein External links eMedicineDictionary Testicular ... of the abdomen de Arteria testicularis es Arteria testicular la Arteria testicularis pl T tnica j drowa pt Art ria testicular ... more details
Since the left testicular vein goes all the way up to the left renal vein before it empties, this results ... stub Veins Category Veins of the torso pt Veia testicular ... more details
protein Name Testicular receptor 2 nuclear receptor subfamily 2, group C, member 1 caption image width HGNCid 7971 Symbol NR2C1 AltSymbols TR2 EntrezGene 7181 OMIM 601529 RefSeq NM 003297 UniProt P13056 PDB ECnumber Chromosome 12 Arm q Band 22 LocusSupplementaryData protein Name Testicular receptor 4 nuclear receptor subfamily 2, group C, member 2 caption image width HGNCid 7972 Symbol NR2C2 AltSymbols TR4 EntrezGene 7182 OMIM 601426 RefSeq NM 003298 UniProt P49116 PDB ECnumber Chromosome 3 Arm p Band 25 LocusSupplementaryData The testicular receptor proteins are members of the nuclear receptor family of intracellular transcription factor s. ref name pmid12361719 cite journal author Lee YF, Lee HJ, Chang C title Recent advances in the TR2 and TR4 orphan receptors of the nuclear receptor superfamily journal J. Steroid Biochem. Mol. Biol. volume 81 issue 4 5 pages 291 308 year 2002 pmid 12361719 doi 10.1016 S0960 0760 02 00118 8 ref There are two forms of the receptor, testicular receptor 2 TR2 and testicular receptor 4 TR4 , each encode by a separate gene gene NR2C1 and gene NR2C2 respectively . 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 pmid 2597158 doi 10.1016 S0006 291X 89 80028 2 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 pmid 8661150 doi 10.1006 geno.1996.0368 ref ref name pmid8016112 cite journal author Chang C, Da Silva SL, Ideta R, Lee Y, Yeh S, Burbach JP title Human and rat ... receptors Category Transcription factors es Receptor testicular ... more details
Infobox Disease Name Testicular Cancer Image Seminoma of the Testis.jpg Caption 7.4 5.5 cm seminoma in a castration ... eMedicine mult eMedicine2 med 863 MeshID D013736 Testicular cancer is cancer that develops in the testicle ... of testicular cancer are made each year. ref Cite book year 2003 title Cancer Facts and Figures ... of testicular cancer is roughly 1 in 250 0.4 . It is most common among males aged 15 35 years. Citation needed date July 2010 Testicular cancer has one of the highest cure rates of all cancers in excess ... health conditions and treatments testicular cancer what will happen survival rates for testicular ... such as testicular microlithiasis , epididymal cyst s, appendix testis hydatid of Morgagni , and so on which may be painful but are non cancerous. Classification Although testicular cancer can be derived from any cell type found in the testicles, more than 95 of testicular cancers are germ cell ... Health Organization Classification system for testicular tumours ref Eble J.N., Sauter G., Epstein ... Mesenchymal tumours of the spermatic cord and testicular adnexae Lipoma Liposarcoma Rhabdomyosarcoma ... fibrous tumour Others Secondary tumours of the testis Signs and symptoms A testicular mass can often ... for testicular cancer in asymptomatic adolescent and adults, which means that men should not perform routine testicular self exams. ref http www.uspreventiveservicestaskforce.org uspstf uspstest.htm ... for testicular cancer does not lead to decreased morbidity and mortality. ref Screening for testicular ... for Healthcare Research and Quality February 2004. http www.ahrq.gov clinic 3rduspstf testicular ... monthly, especially if they have a family history of cancer. ref Testicular Cancer Early Detection ... testicular cancer detection ref Symptoms may include one or more of the following a Swelling medical ... year 2005 publisher McGraw Hill isbn 0071391401 pages 550 553 chapter 82. Testicular Cancer editor2 ... February 15, 2008 title Diagnosis and Treatment of Testicular Cancer journal American Family Physician ... more details
In mathematics , the term torsion free may refer to several unrelated notions In abstract algebra, a group is torsion algebra torsion free if the only element of finite order is the identity. In abstract algebra, a module is torsion free if it has no nonzero torsion element s. In differential geometry, an affine connection is torsion free if its torsion tensor vanishes. See also Torsion disambiguation mathdab ... more details
Torsion field can refer to A torsion tensor in differential geometry. The field used in Einstein Cartan theory and other alternatives to general relativity that involve torsion of spacetime Torsion field pseudoscience , a field alleged to make faster than light communication and paranormal phenomena possible disamb ... more details
In the theory of abelian group s, the torsion subgroup A sub T sub of an abelian group A is the subgroup ... a torsion or periodic group periodic group if every element of A has finite order and is called torsion free if every element of A except the identity element identity is of infinite order. The proof ... section . If A is abelian, then the torsion subgroup T is a characteristic subgroup fully characteristic subgroup of A and the factor group A T is torsion free. There is a covariant functor from the category of abelian groups to the category of torsion groups that sends every group to its torsion subgroup and every homomorphism to its restriction to the torsion subgroup. There is another covariant functor from the category of abelian groups to the category of torsion free groups that sends every group to its quotient by its torsion subgroup, and sends every homomorphism to the obvious induced ... be written as the direct sum of groups direct sum of its torsion subgroup T and a torsion ... of A as a direct sum of a torsion subgroup S and a torsion free subgroup, S must equal T but the torsion ... generated abelian group s. p power torsion subgroups For any abelian group math A, math and any ... the p power torsion subgroup or, more loosely, the p torsion subgroup math A T p g in A exists n in mathbb N , p n g 0 . math The torsion subgroup A sub T sub is isomorphic to the direct sum of its p power torsion subgroups over all prime numbers p math A T bigoplus p in P A T p . math When A is a finite ... p power torsion subgroup of A is a characteristic subgroup fully characteristic subgroup . More strongly, any homomorphism between abelian groups sends each p power torsion subgroup into the corresponding p power torsion subgroup. For each prime number p , this provides a functor from the category of abelian groups to the category of p power torsion groups that sends every group to its p power torsion subgroup, and restricts every homomorphism to the p torsion subgroups. The product over ... more details
dablink For other notions of torsion, see Torsion disambiguation Torsion . In abstract algebra , the term torsion refers to a number of concepts related to elements of finite order in group mathematics ... mathematics group . An element g of G is called a torsion element if g has finite order group theory order . If all elements of G are torsion elements, then G is called a torsion group . If the only torsion element is the identity element , then the group G is called torsion free . Let M be a module ... a torsion element if the cyclic submodule of M generated by m is not free module free . Equivalently, m is torsion if and only if it has a non zero annihilator ring theory annihilator in R . If the ring R is an integral domain, then the set of all torsion elements forms a submodule of M , called the torsion submodule of M , sometimes denoted T M . The module M is called a torsion module if T M M , and is called torsion free if T M 0. Note that when R is only a commutative ring, torsion ... complicated, and the set of torsion elements need not be a submodule. Nevertheless, it is a submodule ... over the ring Z of integer s, and in this case the two notions of torsion coincide. More generally ... the notion of S torsion as follows. An element m of an R module M is called an S torsion element ..., one can take for S to be the set of all non zero divisors of the ring R . In this case, S torsion is frequently called simply torsion, extending the definition above from the case of domain ring theory ... immediately from the definitions that M is torsion free if the ring R is not a domain then torsion is considered ... is torsion free and any vector space over a field K is torsion free when viewed as the module over ..., any nontrivial torsion element either has order two and is conjugate to the element S or has order three and is conjugate to the element ST . In this case, torsion elements do not form a subgroup ..., the module K t K t over the ring R K t of polynomial s in one variable is pure torsion ... more details
Unreferenced stub auto yes date December 2009 A torsion box consists of two skins applied to a core material, usually a grid or framework of some kind. The torsion box functions as a Beam structure beam , but is considerably lighter than a solid beam of the same size without losing much strength. Torsion boxes are used in the construction of airframe s, especially wing s and vertical stabilizer s, in making wooden table furniture table s and door s, and for ski s and snowboard s. DEFAULTSORT Torsion Box Category Structural engineering Tech stub pl Keson lotnictwo ... more details
Wiktionary torsionTorsion is an anatomical event which takes place during the very early part of the life of snail s and slug s of all kinds. In other words, torsion is a gastropod synapomorphy which occurs in all gastropods during larva l development. Torsion is the rotation of the Viscus visceral ... position, this may be only partial detorsion or full detorsion. The torsion or twisting of the visceral ... thumb Trochophore of Haliotis asinina with calcified protoconch pc prior to torsion. File Haliotis asinina protoconch.jpg thumb Protoconch of Haliotis asinina when the torsion is complete. There are two different developmental stages which cause torsion. The first stage is caused by the development ... the second stage of torsion development is achieved by differential Tissue biology tissue ... of the above phases. During torsion the visceral mass remains almost unchanged anatomically. There are, however, other important changes to other internal parts of the gastropod. Before torsion ... parallel down the body. Torsion results in a streptoneural nervous system, where the visceral ... reproductive system . Evolutionary roles The original advantage torsion gave gastropods is unclear. It is further complicated by the fact that torsion brought with it a number of problems. A particular ... and success of the gastropods suggests torsion is either advantageous or at least has no strong .... In evolutionary terms the appearance of an operculum occurred shortly after that of torsion, a possible link with the role of torsion, though there is not sufficient evidence either for or against this theory. There are many other advantages torsion provided gastropods. For Aquatic animal ... conispiral shell allowed gastropods to grow larger but resulted in an unbalanced shell. Torsion allows ..., and thus helps prevent the animal or the shell from falling over. Whatever the original role that torsion played, it is clear that further adaptations linked to torsion provide modern gastropods ... more details
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
dablink For other notions of torsion, see Torsion disambiguation Torsion . In the elementary differential geometry of curves in three dimensions, the torsion of a curve measures how sharply it is twisting. Taken together, the curvature and the torsion of a space curve are analogous to the curvature of a plane curve. For example, they are coefficients in the system of differential equation s for the Frenet frame given by the Frenet Serret formulas . Definition Let C be a space curve in a unit length or natural parametrization and with the unit tangent vector t . If the curvature math kappa math of C at a certain point is not zero then the principal normal vector and the binormal vector at that point are the unit vectors math mathbf n frac mathbf t kappa , quad mathbf b mathbf t times mathbf n , math where the prime denotes the derivative of the vector with respect to the parameter. The torsion math tau math measures the speed of rotation of the binormal vector at the given point. It is found from the equation math mathbf b tau mathbf n . math which means math tau mathbf n cdot mathbf b . math Remark The derivative of the binormal vector is perpendicular to both the binormal and the tangent, hence it has to be proportional to the principal normal vector. The negative sign is simply a matter of convention it is a by product of the historical development of the subject. The radius of torsion , often denoted by , is defined as math sigma frac 1 tau . math Properties A plane curve with non vanishing curvature has zero torsion at all points. Conversely, if the torsion of a regular curve with non vanishing curvature is identically zero, then this curve belongs to a fixed plane. The curvature and the torsion of a helix are constant. Conversely, any space curve with constant non zero curvature and constant torsion is a helix. The torsion is positive for a right handed helix and is negative ... . Then the torsion can be computed from the following formula math tau det left r ,r ,r right over ... more details
infobox disease Name Ovarian torsion Image Gray1170.png Alt Caption Arteries of the female reproductive tract uterine artery, ovarian artery and vaginal arteries. Ovary and ovarian artery visible in upper right. DiseasesDB 31120 ICD10 ICD10 N 83 5 n 80 ICD9 ICD9 620.5 ICDO OMIM MedlinePlus eMedicineSubj article eMedicineTopic 795994 MeshID GeneReviewsID GeneReviewsName Ovarian torsion OT refers to the rotation of the ovary to such a degree as to occlude the ovarian artery and or vein. Epidemiology Ovarian torsion accounts for about 3 of gynecologic emergencies. In 70 percent, it is diagnosed in women between 20 and 39 years. The risk is greater during pregnancy and in the menopause. The risk factors are increased length of the ovarian ligaments, pathologically enlarged ovaries more than 6 cm , tumors, enlarged corpus luteum in pregnancy and jerky movements. Presentation Patients with ovarian torsion often present with sudden onset of sharp and usually unilateral lower abdominal pain, in 70 ... Torsion Overview. http emedicine.medscape.com article 795994 overview ref Use of Doppler ultrasound ... D, Cooney N, Denis AL title Usefulness of Doppler sonography in the diagnosis of ovarian torsion ... Diagnosis of ovarian torsion by three dimensional power Doppler in first trimester of pregnancy ... to the development of torsion. In the reproductive years, regular growth of large corpus luteal ... of torsion. Torsion of the ovary usually occurs with torsion of the fallopian tube as well on their shared ... , torsion happens unilaterally, with slight predominance on the right. Diagnosis Ovarian torsion ... of ovarian torsion was confirmed in only 46 of patients. ref name Bar On cite journal author Bar On S, Mashiach R, Stockheim D, et al. title Emergency laparoscopy for suspected ovarian torsion are we ... seems to be a good predictor of ovarian torsion. Women with pathologically low flow are more ... treatment of ovarian torsion includes laparoscopy to uncoil the torsed ovary and possibly oophoropexy ... more details
Image Mausefalle 300px.jpg thumb 300px A mousetrap powered by a helical torsion spring A torsion spring is a spring device spring that works by Torsion mechanics torsion or twisting that is, a flexible ... actually torque it exerts is proportional to the amount it is twisted. There are two types. A torsion ... axis by torque applied at its ends. A more delicate form used in sensitive instruments, called a torsion ... about its axis. The other type, a helical torsion spring , is a metal rod or wire in the shape of a helix ... torsion spring the forces acting on the wire are actually bending stresses, not Torsional strain ... isbn 0070611416 ref Torsion coefficient As long as they are not twisted beyond their elastic limit , torsion springs obey an angular form of Hooke s law math tau kappa theta , math where math tau , math ... of newton meters radian, variously called the spring s torsion coefficient , torsion elastic modulus ... in a torsion spring is math U frac 1 2 kappa theta 2 math Uses Some familiar examples of uses are the strong helical torsion springs that operate clothespin s and traditional springloaded bar type mousetrap s. Other uses are in the large coiled torsion springs used to counter balance the weight ... on some sedan car sedan s. Small coiled torsion springs are often used to operate pop up doors found on small consumer goods like digital camera s and compact disc players. Other more specific uses Torsion ... also uses the torsion spring principle. The torsion pendulum used in torsion pendulum clock s is a wheel shaped weight suspended from its center by a wire torsion spring. The weight rotates about the axis ... by the clock s gears. The torsion catapult or mangonel is a medieval siege engine invented by the ancient Greeks. It uses a torsion spring consisting of twisted ropes to swing an arm that throws a heavy ... spiral shaped torsion spring that pushes the balance wheel back toward its center position as it rotates back and forth. The balance wheel and spring function similarly to the torsion pendulum ... more details
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