376 research outputs found
Radiatively induced CPT-odd Chern-Simons term in massless QED
In this work, we study the radiative generation of the CPT-odd
Lorentz-violating Chern-Simons term, arising from massless fermions. For this,
we calculate the vacuum polarization tensor using the 't Hooft-Veltman
regularization scheme, in which the result obtained for the coefficient of the
Chern-Simons term is . This result
leads us precisely to the same conductivity found in Weyl semimetals, i.e., the
't Hooft-Veltman regularization scheme is the correct one to be used in this
context. We also discuss the temperature dependence of , in which
at high temperature, and
. In the context of Weyl semimetals, these
results are in accordance with the fact that the chiral magnetic current
vanishes at high temperature, whereas the anomalous Hall current
remains unaffected by the finite temperature.Comment: 13 pages, accepted for publication in Europhys. Let
Nonanalyticity of the induced Carroll-Field-Jackiw term at finite temperature
In this paper, we discuss the behavior of the Carroll-Field-Jackiw (CFJ)
coefficient arising due to integration over massive fermions, and the
modification suffered by its topological structure in the finite temperature
case. Our study is based on the imaginary time formalism and summation over the
Matsubara frequencies. We demonstrate that the self-energy of photon is
non-analytic for the small limit, i.e., the static limit and the long wavelength limit
do not commute, while the tensorial structure of the CFJ term holds in both
limits.Comment: 12 pages, 1 figur
Induced Chern-Simons modified gravity at finite temperature
We calculate the linearized four-dimensional gravitational Chern-Simons term
at the finite temperature, show its finiteness and explicitly demonstrate that
its transversal part matches the known result for the chiral vortical
conductivity.Comment: 14 pages, version accepted to JHE
Neutron Transfer reactions induced by 8Li on 9Be
Angular distributions for the elastic scattering of 8Li on 9Be and the
neutron transfer reactions 9Be(8Li,7Li)10Be and 9Be(8Li,9Li)8Be have been
measured with a 27 MeV 8Li radioactive nuclear beam. Spectroscopic factors for
8Li|n=9Li and 7Li|n=8Li bound systems were obtained from the comparison between
the experimental differential cross section and finite-range DWBA calculations
with the code FRESCO. The spectroscopic factors obtained are compared to shell
model calculations and to other experimental values from (d,p) reactions. Using
the present values for the spectroscopic factor, cross sections for the direct
neutron-capture reactions 7Li(n,g)8Li and 8Li(n,g)9Li were calculated in the
framework of a potential model.Comment: 24 pages, 8 Figures, submitted as regular article to PR
Identification of Recurrent Mutations in the microRNA-Binding Sites of B-Cell Lymphoma-Associated Genes in Follicular Lymphoma
Follicular lymphoma (FL) is a common indolent B-cell lymphoma that can transform into the more aggressive transformed FL (tFL). However, the molecular process driving this transformation is uncertain. In this work, we aimed to identify microRNA (miRNA)-binding sites recurrently mutated in follicular lymphoma patients, as well as in transformed FL patients. Using whole-genome sequencing data from FL tumors, we discovered 544 mutations located in bioinformatically predicted microRNA-binding sites. We then studied these specific regions using targeted sequencing in a cohort of 55 FL patients, found 16 recurrent mutations, and identified a further 69 variants. After filtering for QC, we identified 21 genes with mutated miRNA-binding sites that were also enriched for B-cell-associated genes by Gene Ontology. Over 40% of mutations identified in these genes were present exclusively in tFL patients. We validated the predicted miRNA-binding sites of five of the genes by luciferase assay and demonstrated that the identified mutations in BCL2 and EZH2 genes impaired the binding efficiency of miR-5008 and miR-144 and regulated the endogenous levels of messenger RNA (mRNA)
Morpho/Proteomic Comparative between High Grade Pleomorphic Sarcoma and Metastasis Diagnosed in an Old Captive Common Hippo
Old age is a risk factor for cancer development in humans and animals, and studies have shown that tumors in animals are acceptable models for studying human cancers, considering the similarities between their factors. This work was conducted in a 53-year-old captive female common hippo (Hippopotamus amphibious) with a left leg tumor and metastatic mass. Histopathological and immunohistochemical analyses were carried out with a final diagnosis of a high grade pleomorphic sarcoma. A proteomic study using mass spectrometry was added in order to identify further aspects of the primary tumor and metastasis which could improve our understanding, and each tissue showed a proteomic profile indicative of its pathologic state with significant differences between healthy tissue, primary and metastatic tumors. Low levels of beta-actin in primary tumors were identified, and this may be associated with a possible consequence of cytoskeleton dynamic modification. In metastatic tissue, these dynamics may be affected by the presence of HSP chaperone 60.FAPESP: 2012/02514-9Univ Fed Sao Paulo, Inst Ciencias Ambientais Quim & Farmaceut, BR-04039032 Diadema, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, BR-04023062 Sao Paulo, SP, BrazilAC Camargo Canc Ctr, Dept Patol, BR-01509010 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Inst Ciencias Ambientais Quim & Farmaceut, BR-04039032 Diadema, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, BR-04023062 Sao Paulo, SP, BrazilWeb of Scienc
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