1,274 research outputs found
Constrained Analysis of Topologically Massive Gravity
We quantize the Einstein gravity in the formalism of weak gravitational
fields by using the constrained Hamiltonian method. Special emphasis is given
to the 2+1 spacetime dimensional case where a (topological) Chern-Simons term
is added to the Lagrangian.Comment: 15 pages, IF-UFRJ-21/9
Densidade mineral óssea, vitamina D e terapia anticonvulsivante
The aim of this study was to assess bone mineral density and vitamin D metabolism in patients on chronic anticonvulsant therapy. METHODS: Sixty-nine men, outpatients on chronic anticonvulsant therapy, who had been treated for at least 5 years, were studied, comparing them to thirty healthy controls. Bone mineral density was measured as well as serum levels of calcium, ionized calcium, alkaline phosphatase, PTH, 25-hydroxycholecalciferol and 1,25-dihydroxycholecalciferol. RESULTS: No differences in bone mineral density, serum levels of vitamin D and intact-PTH were observed between patients and controls. Bone mineral density was not associated with chronic anticonvulsant therapy. CONCLUSION: Those adult patients who were on chronic anticonvulsant therapy and who lived in low latitude regions had normal bone mineral density as well as vitamin D serum levels.O objetivo deste estudo foi avaliar a densidade mineral óssea e o metabolismo da vitamina D em usuários crônicos de anticonvulsivantes. MÉTODOS: Foram estudados 69 pacientes ambulatoriais, masculinos, usuários crônicos de anticonvulsivantes por período mínimo de 5 anos e comparados a 30 controles normais. Foram efetuadas as medidas da densidade mineral óssea e dos níveis plasmáticos do cálcio, cálcio iônico, fosfatase alcalina, paratormônio, 25-hidroxi-colecalciferol e 1,25-di-hidroxi-colecalciferol. RESULTADOS: Nenhuma diferença na densidade mineral óssea e nos níveis plasmáticos da vitamina D e paratormônio foram observadas entre os pacientes e os controles. A densidade mineral óssea não se mostrou associada ao uso crônico de anticonvulsivantes. CONCLUSÕES: Pacientes adultos, do sexo masculino, usuários crônicos de anticonvulsivantes, residentes em regiões ensolaradas, têm densidade mineral óssea e níveis plasmáticos de vitamina D normais61662
Infection By The Human Papillomavirus In Teenagers Sexually Active: Clinic And Subclinic Manifestations.
This research studies the association of the cervical condyloma with the intraepithelial neoplasia, during sex activity, pregnancy, diagnose methods, cytology and colposcopy in teenagers. The objective of this research is to study the propaedeutics for the uterine coli condyloma diagnose in a group of teenagers. For this purpose, we have studied 131 teenagers sexually active with ages between 14 and 19 years and presenting histologically confirmed uterine coli condyloma. Association with intraepithelial neoplasia, sexual activity duration, method of diagnose, pregnancy analysis, cytology and colposcopy results and association with vulva and vagina injuries were evaluated. The high association rate with condyloma and intraepithelial neoplasia after a short time of sexual activity and the none presence of macroscopic warts in the genital organs in 80% of cases presenting cervical condyloma, demonstrate that: a more careful investigation with colposcopy and biopsy of the inferior genitals of the women-teenagers sexually active is needed, when presenting modified cervical cytology.113494895
Characterization of oil shale residue and rejects from irati formation by electron paramagnetic resonance
In this study, sedimentary organic matter of oil shale rejects, calschist, shale fine and the so called retorted shale from Irati formation was characterized. EPR was used to analyse the samples regarding loss of signal in g = 2.003 associated to the organic free radical with the calcined samples and washing with hydrogen peroxide. The radical signal was detected in all samples, however, for the calschist and shale fine samples another signal was identified at g = 2.000 which disappeared when the sample was heated at 400 ºC. Hydrogen peroxide washing was also performed and it was noted that after washing the signal appeared around g = 2.000 for all samples, including retorted shale, which might be due to the quartz E1 defect
Negative c-axis magnetoresistance in graphite
We have studied the c-axis interlayer magnetoresistance (ILMR), R_c(B) in
graphite. The measurements have been performed on strongly anisotropic highly
oriented pyrolytic graphite (HOPG) samples in magnetic field up to B = 9 T
applied both parallel and perpendicular to the sample c-axis in the temperature
interval 2 K < T < 300 K. We have observed negative magnetoresistance, dR_c/dB
< 0, for B || c-axis above a certain field B_m(T) that reaches its minimum
value B_m = 5.4 T at T = 150 K. The results can be consistently understood
assuming that ILMR is related to a tunneling between zero-energy Landau levels
of quasi-two-dimensional Dirac fermions, in a close analogy with the behavior
reported for alpha-(BEDT-TTF)2I3 [N. Tajima et al., Phys. Rev. Lett. 102,
176403 (2009)], another multilayer Dirac electron system.Comment: 14 pages, including 4 figure
Decrease in Bone Mass in Women After Liver Transplantation: Associated Factors
AbstractBackgroundIn the future, an increasing number of female liver transplant recipients will reach the climacteric with osteoporosis as a common complication. We evaluated the factors associated with decreased bone mass among women after liver transplantation.MethodsA prospective, cross-sectional study of 23 outpatient transplant recipients followed from February 2009 to March 2010 included women of age ≥35 years after liver transplantations ≥1 year prior. We recorded patient histories, liver enzyme levels, as well as bone mineral densities measured at the lumbar spine and femur. Statistical analysis used Fisher's exact test, simple odds ratio (OR), and Spearman's rank correlation coefficient.ResultsThe mean patient age was 52.5 ± 11 years with 30.4% premenopausal, and 69.6% perimenopausal or postmenopausal. Approximately 21% showed osteoporosis and 35%, a low bone mass. Postmenopausal women: OR 69.0 (95% CI 2.89–1647.18; P < .0001), aged ≥49 years: OR 13.33 (95% CI 1.78–100.15; P = .0123) and receiving a transplant after 44 years of age: OR 49.50 (95% CI 3.84–638.43; P < .0001) were associated with a lower bone mass. Having undergone transplantation for more than 5.8 years lowered the risk of bone mass change: OR 0.11 (95% CI 0.02–0.78; P = .0361). Clinical and laboratory variables, including corticosteroid use, were not associated with decreased bone mass.ConclusionUnderstanding the prevalence and factors associated with osteoporosis among female liver transplant recipients is important to enhance the strategies to diagnose and treat these women, seeking to improve their quality of life
INFLUÊNCIA DA DISPONIBILIDADE DE SOMBRA A PASTO SOBRE A MORFOLOGIA ESPERMÁTICA DE TOUROS DA RAÇA BRAHMAN (Bos taurus indicus) CRIADOS NA REGIÃO SUDESTE DO BRASIL
Under heat stress conditions, testicular degeneration can occur, even on zebu animals. Therefore, the aim of this work was to verify the occurrence of any possible effect of shadow availability on pasture on spermatic morphology of Brahman Bulls on Brazil Southeast. Five animals were allocated on pasture with shadow availability, and five bulls were allocated on pasture without any kind of shadow. No difference was observed (P>0.05) in any of the characteristics analyzed when Brahman bulls were maintained on pastures with or without shadow availability
Bosonization and Duality in Arbitrary Dimensions: New Results
A generic massive Thirring Model in three space-time dimensions exhibits a
correspondence with a topologically massive bosonized gauge action associated
to a self-duality constraint, and we write down a general expression for this
relationship.
We also generalize this structure to dimensions, by adopting the
so-called doublet approach, recently introduced. In particular, a non-
conventional formulation of the bosonization technique in higher dimensions (in
the spirit of ), is proposed and, as an application, we show how fermionic
(Thirring-like) representations for bosonic topologically massive models in
four dimensions may be built up.Comment: Revised version, to appear in Phys. Rev.
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