Two loops calculation in chiral perturbation theory and the unitarization program of current algebra

In this paper we compare two loop Chiral Perturbation Theory (ChPT) calculation of pion-pion scattering with the unitarity second order correction to the current algebra soft-pion theorem. It is shown that both methods lead to the same analytic structure for the scattering amplitude.Comment: 13 pages, Revtex 3.0, no figures, submitted to Phys. Lett.

Pion-Pion Phase-Shifts and the Value of Quark-Antiquark Condensate in the Chiral Limit

We use low energy pion-pion phase-shifts in order to make distinction between the alternatives for the value of the quark-antiquark condensate $B_0$ in the chiral limit. We will consider the amplitude up to and including ${\cal O}(p^4)$ contributions within the Standard and Generalized Chiral Perturbation Theory frameworks. They are unitarized by means of Pad\'e approximants in order to fit experimental phase-shifts in the resonance region. As the best fits correspond to $\alpha = \beta = 1$, we conclude that pion-pion phase-shift analysis favors the standard ChPT scenario, which assumes just one, large leading order parameter $_{_0}$.Comment: 5 pages, 3 figures and 1 tabl

Diffraction and an infrared finite gluon propagator

We discuss some phenomenological applications of an infrared finite gluon propagator characterized by a dynamically generated gluon mass. In particular we compute the effect of the dynamical gluon mass on $pp$ and ${\bar{p}}p$ diffractive scattering. We also show how the data on $\gamma p$ photoproduction and hadronic $\gamma \gamma$ reactions can be derived from the $pp$ and $\bar{p}p$ forward scattering amplitudes by assuming vector meson dominance and the additive quark model.Comment: 4 pages, 7 figures, added references and figures, changed structure. Contribution to Proceedings of XVIIIth Reuniao de Trabalho sobre Interacoes Hadronicas, Sao Paulo, Brazil, 22-24 May, 200

Nanofibrillated bacterial cellulose and pectin edible films added with fruit purees.

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Pion-delta sigma-term

We use a configuration space chiral model in order to evaluate nucleon and delta sigma-terms. Analytic expressions are consistent with chiral counting rules and give rise to expected non-analytic terms in the chiral limit. We obtain the results $\sigma_N=46$ MeV and $\sigma_{\Delta}=32$ MeV, which are very close to values extracted from experiment and produced by other groups.Comment: 18 pages, 4 figure

Cephalometric and anthropometric data of obstructive apnea in different age groups

Pacientes com a síndrome da apneia obstrutiva do sono (SAOS) geralmente apresentam alterações na morfologia das vias aéreas superiores e/ou na distribuição da gordura corporal, que podem ocorrer durante a vida e aumentar a gravidade da SAOS com a idade. Correlacionar medidas cefalométricas e antropométricas com a gravidade da SAOS em diferentes faixas etárias. Estudo retrospectivo de medidas cefalométricas e antropométricas de 102 pacientes portadores de SAOS. Os pacientes foram divididos em três faixas etárias (≥20 e <40 anos, ≥40 e <60 anos, e ≥60 anos). Foi realizada correlação de Pearson destas medidas com o índice de apneia-hipopneia (IAH) na amostra completa e depois por faixa etária. As medidas cefalométricas MP-H (distância entre o plano mandibular e o osso hioide) e PNS-P (distância entre a espinha nasal posterior e a ponta do palato mole) e as circunferências cervical e abdominal apresentaram correlação estatisticamente significante com o IAH tanto na amostra total quanto na faixa de <40 e ≥ 60 anos. Estas variáveis não mostraram correlação significante com as outras duas faixas etárias (≤ 40 e ≥ 60 anos).As medidas cefalométricas MP-H e PNS-P e as circunferências cervical e abdominal apresentaram correlação com a gravidade da SAOS em pacientes na faixa etária de ≥40 e <60 anos811Patients with obstructive sleep apnea syndrome usually present with changes in upper airway morphology and/or body fat distribution, which may occur throughout life and increase the severity of obstructive sleep apnea syndrome with age. To correlate cephalometric and anthropometric measures with obstructive sleep apnea syndrome severity in different age groups. A retrospective study of cephalometric and anthropometric measures of 102 patients with obstructive sleep apnea syndrome was analyzed. Patients were divided into three age groups (≥20 and <40 years, ≥40 and <60 years, and ≥60 years). Pearson's correlation was performed for these measures with the apnea-hypopnea index in the full sample, and subsequently by age group. The cephalometric measures MP-H (distance between the mandibular plane and the hyoid bone) and PNS-P (distance between the posterior nasal spine and the tip of the soft palate) and the neck and waist circumferences showed a statistically significant correlation with apnea-hypopnea index in both the full sample and in the ≥40 and <60 years age group. These variables did not show any significant correlation with the other two age groups (<40 and ≥60 years). Cephalometric measurements MP-H and PNS-P and cervical and waist circumfer- ences correlated with obstructive sleep apnea syndrome severity in patients in the ≥40 and <60 age group

IFNγ and iNOS-mediated alterations in the bone marrow and thymus and its impact on Mycobacterium avium-induced thymic atrophy [preprint]

Disseminated infection with the high virulence strain of Mycobacterium avium 25291 lead to progressive thymic atrophy. We previously uncovered that M. avium-induced thymic atrophy is due to increased levels of glucocorticoids synergizing with nitric oxide (NO) produced by interferon gamma (IFNγ) activated macrophages. Where and how these mediators are playing, was yet to be understood. We hypothesized that IFNγ and NO might be affecting bone marrow (BM) T cell precursors and/or T cell differentiation in the thymus. We show that M. avium infection causes a reduction on the percentage of lymphoid-primed multipotent progenitors (LMPP) and common lymphoid progenitors (CLP). Additionally, BM precursors from infected mice are unable to reconstitute thymi of RAGKO mice in an IFNγ-dependent way. Thymi from infected mice presents a NO-dependent inflammation. When transplanted under the kidney capsule of non-infected mice, thymic stroma from infected mice is unable to sustain T cell differentiation. Finally, we observed increased thymocyte death via apoptosis after infection, independent of both IFNγ and iNOS, and a decrease on activated caspase-3 positive thymocytes, that was not observed in the absence of iNOS expression. Together our data suggests that M. avium-induced thymic atrophy results from a combination of impairments, mediated by IFNγ and NO, affecting different steps of T cell differentiation from T cell precursor cells in the BM to the thymic stroma and thymocytes

A INTENÇÃO DE LEALDADE À UNIVERSIDADE A PARTIR DA ANÁLISE DO PERFIL DE ALUNOS DO CURSO DE ADMINISTRAÇÃO DE UMA UNIVERSIDADE PÚBLICA

Universidades cada vez mais necessitam ter um gerenciamento profissional, especialmente, objetivando o atendimento às necessidades dos alunos. A lealdade de alunos pode contribuir para a existência de benefícios pessoais, sociais e institucionais. Entretanto, algumas características interferem na lealdade daqueles que buscam serviços na área de educação. Buscando conhecer as características que influenciam na lealdade de alunos universitários, o presente artigo buscou realizar uma pesquisa descritiva e quantitativa com alunos do curso de Administração de uma universidade pública no sul do Brasil. Os resultados indicam que alunos em geral sentem-se leais, e nesta pesquisa as mulheres. Alunos de maior idade tendem e ser mais leais, assim como aqueles que estudaram em escolas públicas e nasceram em outra cidade. A lealdade varia em relação a semestres que o aluno estava cursando