Absence of resonant enhancements in some inclusive rates

A toy model is defined and solved perturbatively with the aim of examining some claimed "resonant" enhancements of certain reaction rates that enter popular models of leptogenesis. We find: a) that such enhancements are absent; and b) that the perturbative solution, as done correctly using finite- temperature field theory, is well defined without the "resumming" procedures found in the literature. The pathologies that led to the perceived need for these procedures are an artifact of uncritical use of weighted vacuum cross- sections in the determination of rates, without adequate attention to the effects of the medium upon the single particle states within it.Comment: 11 pages, no figures. Some typos corrected. More typos correcte

Discrete Symmetries and Generalized Fields of Dyons

We have studied the different symmetric properties of the generalized Maxwell's - Dirac equation along with their quantum properties. Applying the parity (\mathcal{P}), time reversal (\mathcal{T}), charge conjugation (\mathcal{C}) and their combined effect like parity time reversal (\mathcal{PT}), charge conjugation and parity (\mathcal{CP}) and \mathcal{CP}T transformations to varius equations of generalized fields of dyons, it is shown that the corresponding dynamical quantities and equations of dyons are invariant under these discrete symmetries. Abstract Key words- parity, time reversal, charge-conjugation, dyons Abstract PACS No.- 14.80 Hv

Influence of Heat Treatment Temperature on Fatigue Toughness in Medium-Carbon High-Strength Steels

Current research has demonstrated that the tempering temperature affects the martensitic transformation of medium-carbon high-strength steels. This temperature plays an important role in the final microstructure, percentage ratios of martensite to ferrite phases and, consequently, in the mechanical properties and the fatigue response. So far, the relationship between the martensitic tempering temperature and the cyclic deformation properties is not clearly understood. Moreover, the effect of the martensitic tempering temperature on fatigue toughness has not been studied yet. Therefore, this paper aims to study, in a systematic manner, the fatigue toughness of medium-carbon high-strength steels heat treated at different temperatures under fully reversed strain-controlled conditions

Multicentric study of liver transplantation in patients with hepatocellular carcinoma in brazil- preliminary data of 913 patients

621445A446

Multimodal MRI-based study in patients with SPG4 mutations

Mutations in the SPG4 gene (SPG4-HSP) are the most frequent cause of hereditary spastic paraplegia, but the extent of the neurodegeneration related to the disease is not yet known. Therefore, our objective is to identify regions of the central nervous system damaged in patients with SPG4-HSP using a multi-modal neuroimaging approach. In addition, we aimed to identify possible clinical correlates of such damage. Eleven patients (mean age 46.0 ± 15.0 years, 8 men) with molecular confirmation of hereditary spastic paraplegia, and 23 matched healthy controls (mean age 51.4 ± 14.1years, 17 men) underwent MRI scans in a 3T scanner. We used 3D T1 images to perform volumetric measurements of the brain and spinal cord. We then performed tract-based spatial statistics and tractography analyses of diffusion tensor images to assess microstructural integrity of white matter tracts. Disease severity was quantified with the Spastic Paraplegia Rating Scale. Correlations were then carried out between MRI metrics and clinical data. Volumetric analyses did not identify macroscopic abnormalities in the brain of hereditary spastic paraplegia patients. In contrast, we found extensive fractional anisotropy reduction in the corticospinal tracts, cingulate gyri and splenium of the corpus callosum. Spinal cord morphometry identified atrophy without flattening in the group of patients with hereditary spastic paraplegia. Fractional anisotropy of the corpus callosum and pyramidal tracts did correlate with disease severity. Hereditary spastic paraplegia is characterized by relative sparing of the cortical mantle and remarkable damage to the distal portions of the corticospinal tracts, extending into the spinal cord.Mutations in the SPG4 gene (SPG4-HSP) are the most frequent cause of hereditary spastic paraplegia, but the extent of the neurodegeneration related to the disease is not yet known. Therefore, our is to identify regions of the central nervous system damag102FAPESP - FUNDAÇÃO DE AMPARO A PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR2011/21521-3sem informaçãoFink, J.K., Hereditary spastic paraplegia: Clinico-pathologic features and emerging molecular mechanisms (2013) Acta Neuropathol, 126, pp. 307-328. , PMID: 23897027Depienne, C., Fedirko, E., Forlani, S., Cazeneuve, C., Ribaï, P., Exon deletions of SPG4 are a frequent cause of hereditary spastic paraplegia (2007) J Med Genet, 44, pp. 281-284. , PMID: 17098887Charvin, D., Cifuentes-Diaz, C., Fonknechten, N., Joshi, V., Hazan, J., Mutations of SPG4 are responsible for a loss of function of spastin, an abundant neuronal protein localized in the nucleus (2003) Hum Mol Genet, 12, pp. 71-78. , PMID: 12490534França, M.C., Jr., Dogini, D.B., D'Abreu, A., Teive, H.A., Munhoz, R.P., SPG4-related hereditary spastic paraplegia: Frequency and mutation spectrum in Brazil (2014) Clin Genet, 86, pp. 194-196. , PMID: 24033003Duning, T., Warnecke, T., Schirmacher, A., Schiffbauer, H., Lohmann, H., Specific pattern of early white-matter changes in pure hereditary spastic paraplegia (2010) MovDisord, 25, pp. 1986-1992França, M.C., Jr., Yasuda, C.L., Pereira, F.R., D'Abreu, A., Lopes-Ramos, C.M., White and grey matter abnormalities in patients with SPG11 mutations (2012) J NeurolNeurosurg Psychiatry, 83, pp. 828-833. , PMID: 22696581Le Bihan, D., Mangin, J.F., Poupon, C., Clark, C.A., Pappata, S., Diffusion tensor imaging: Concepts and applications (2001) J MagnReson Imaging, 13, pp. 534-546. , PMID: 11276097Schüle, R., Holland-Letz, T., Klimpe, S., Kassubek, J., Klopstock, T., The Spastic Paraplegia Rating Scale (SPRS): A reliable and valid measure of disease severity (2006) Neurology, 67, pp. 430-434. , PMID: 16894103Dale, A.M., Fischl, B., Sereno, M.I., Cortical surface-based analysis I: Segmentation and surface reconstruction (1999) NeuroImage, 9, pp. 179-194. , PMID: 9931268Fischl, B., Dale, A.M., Measuring the thickness of the human cerebral cortex from magnetic resonance images (2000) ProcNatlAcadSci U S A, 97, pp. 11050-11055. , PMID: 10984517Fischl, B., Salat, D.H., Busa, E., Albert, M., Dieterich, M., Whole brain segmentation: Automated labeling of neuroanatomical structures in the human brain (2002) Neuron, 33, pp. 341-355. , PMID: 11832223Desikan, R.S., Ségonne, F., Fischl, B., Quinn, B.T., Dickerson, B.C., An automated labeling system for subdividing the human cerebral cortex on mri scans into gyral based regions of interest (2006) NeuroImage, 31, pp. 968-980. , PMID: 16530430Smith, S.M., Jenkinson, M., Johansen-Berg, H., Rueckert, D., Nichols, T.E., Ract-based spatial statistics: Voxelwise analysis of multi-subject diffusion data (2006) Neuroimage, 31, p. 1487e505. , PMID: 16624579Lebel, C., Walker, L., Leemans, A., Phillips, L., Beaulieu, C., Microstructural maturation of the human brain from childhood to adulthood (2008) Neuroimage, 40, pp. 1044-1055. , PMID: 18295509Bergo, F.P.G., França, M.C., Jr., Chevis, C.F., Cendes, F., SpineSeg: A segmentation and measurement tool for evaluation of spinal cord atrophy (2012) CISTI'2012 (7? Conferencia Ibérica de Sistemas y Tecnologia de Información), pp. 400-403. , Madrid, Spain: IEEEFitzgibbon, A., Pilu, M., Fisher, R.B., Direct least square fitting of ellipses (1999) IEEE Trans Patt Anal Mach Intel, 21, pp. 476-480Kassubek, J., Sperfeld, A.D., Baumgartner, A., Huppertz, H.J., Riecker, A., Brain atrophy in pure and complicated hereditary spastic paraparesis: A quantitative 3D MRI study (2006) Eur J Neurol, 13, pp. 880-886. , PMID: 16879300Uttner, I., Baumgartner, A., Sperfeld, A.D., Kassubek, J., Cognitive performance in pure and complicated hereditary spastic paraparesis: A neuropsychological and neuroimaging study (2007) Neurosci Lett, 419, pp. 158-161. , PMID: 17485167McDermott, C., White, K., Bushby, K., Shaw, P., Hereditary spastic paraparesis: A review of new developments (2000) J Neurol Neurosurg Psychiatry, 69, pp. 150-160. , PMID: 10896685Garaci, F., Toschi, N., Lanzafame, S., Meschini, A., Bertini, E., Diffusion tensor imaging in SPG11- and SPG4-linked hereditary spastic paraplegia (2014) Int J Neurosci, 124, pp. 261-270. , PMID: 23968121Hedera, P., Eldevik, O.P., Maly, P., Rainier, S., Fink, J.K., Spinal cord magnetic resonance imaging in autosomal dominant hereditary spastic paraplegia (2005) Neuroradiology, 47, pp. 730-734. , PMID: 16143870Salinas, S., Carazo-Salas, R.E., Proukakis, C., Schiavo, G., Warner, T.T., Spastin and microtubules: Functions in health and disease (2007) J Neurosci Res, 85, pp. 2778-2782. , PMID: 17348041Karle, K.N., Schüle, R., Klebe, S., Otto, S., Frischholz, C., Electrophysiological characterisation of motor and sensory tracts in patients with hereditary spastic paraplegia (HSP) (2013) Orphanet J Rare Dis, 9 (8), p. 158. , PMID: 24107482Sun, S.W., Liang, H.F., Cross, A.H., Song, S.K., Evolving Wallerian degeneration after transient retinal ischemia in mice characterized by diffusion tensor imaging (2008) Neuroimage, 40, pp. 1-10. , PMID: 18187343Concha, L., Gross, D.W., Wheatley, B.M., Beaulieu, C., Diffusion tensor imagingof time-dependent axonal and myelin degradation after corpus callosotomyin epilepsy patients (2006) Neuroimage, 32, pp. 1090-1099. , PMID: 16765064Murphy, S., Gorman, G., Beetz, C., Byrne, P., Dytko, M., Dementia in SPG4 hereditary spastic paraplegia: Clinical, genetic, and neuropathologic evidence (2009) Neurology, 73, pp. 378-384. , PMID: 19652142White, K.D., Ince, P.G., Lusher, M., Lindsey, J., Cookson, M., Clinical and pathologic findings in hereditary spastic paraparesis with spastin mutation (2000) Neurology, 55, pp. 89-94. , PMID: 10891911Branco, L.M., De Albuquerque, M., De Andrade, H.M., Bergo, F.P., Nucci, A., Spinal cord atrophy correlates with disease duration and severity in amyotrophic lateral sclerosis (2014) Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration, 15, pp. 93-97. , PMID: 25382834Aghakhanyan, G., Martinuzzi, A., Frijia, F., Vavla, M., Hlavata, H., Brainwhitematterinvolvement in hereditaryspasticparaplegias: Analysis with multiplediffusiontensorindices (2014) AJNR Am J Neuroradiol, 35, pp. 1533-1538. , PMID: 24788132Verstraete, E., Van Den Heuvel, M.P., Veldink, J.H., Blanken, N., Mandl, R.C., Motor network degeneration in amyotrophic lateral sclerosis: A structural and functional connectivity study (2010) PLoS One, 5, p. e13664. , PMID: 2106068