Branching and annihilating Levy flights

We consider a system of particles undergoing the branching and annihilating reactions A -> (m+1)A and A + A -> 0, with m even. The particles move via long-range Levy flights, where the probability of moving a distance r decays as r^{-d-sigma}. We analyze this system of branching and annihilating Levy flights (BALF) using field theoretic renormalization group techniques close to the upper critical dimension d_c=sigma, with sigma<2. These results are then compared with Monte-Carlo simulations in d=1. For sigma close to unity in d=1, the critical point for the transition from an absorbing to an active phase occurs at zero branching. However, for sigma bigger than about 3/2 in d=1, the critical branching rate moves smoothly away from zero with increasing sigma, and the transition lies in a different universality class, inaccessible to controlled perturbative expansions. We measure the exponents in both universality classes and examine their behavior as a function of sigma.Comment: 9 pages, 4 figure

Validity And Reliability Of A Self-efficacy Expectancy Scale For Adherence To Antiretroviral Therapy For Parents And Carers Of Children And Adolescents With Hiv/aids [validação E Reprodutibilidade De Uma Escala De Auto-eficácia Para Adesão Ao Tratamento Anti-retroviral Em Pais Ou Cuidadores De Crianças E Adolescentes Vivendo Com Hiv/aids]

Objective: To validate and evaluate the reproducibility of a self-efficacy (SE) scale for adherence to antiretroviral therapy in children and adolescents with HIV/AIDS, taking into account the perspective of parents/guardians. Methods: The study was carried out at the Hospital-Dia, Centro de Referência e Treinamento em DST/AIDS (CRT/SP), in São Paulo, Brazil. The parents/guardians of 54 children and adolescents aged 6 months to 20 years were interviewed during routine consultations at our service. Data on SE were collected using the Self-Efficacy for Following Anti-Retroviral Prescription Scale, and SE scores were calculated in two different ways: factor analysis and a predefined formula. The scale's internal consistency was verified using Cronbach's α coefficient. Validity was tested by comparing the mean scores of a group of patients who did adhere to antiretroviral treatment with those of a group that did not (Mann-Whitney test) and by calculating the Spearman correlation coefficient for agreement between scores and clinical parameters. Reproducibility was verified using the Wilcoxon test, intraclass correlation coefficients (ricc) and Bland-Altman plots. Results: The SE scale demonstrated good internal consistency (α = 0.87) and good reproducibility (r icc = 0.69 and r icc = 0.75). In terms of validity, the SE scale was capable of differentiating adherent patients from those who did not adhere to their antiretroviral treatment (p = 0.002) and exhibited a significant correlation with CD4 counts (r = 0.28; p = 0.04). Conclusions: The SE scale can be used to assess adherence to antiretroviral therapy in children and adolescents with HIV/AIDS, taking into account the perspective of parents/carers. Copyright © 2008 by Sociedade Brasileira de Pediatria.8414146Matida, L.H., da Silva, M.H., Tayra, A., Succi, R.C., Gianna, M.C., Gonçalves, A., Prevention of mother-to-child transmission of HIV in São Paulo State, Brazil: An update (2005) AIDS, 19 (SUPPL. 4), pp. S37-S41Gibb, D.M., Goodall, R.L., Giacomet, V., McGee, L., Compagnucci, A., Lyall, H., Paediatric European Network for Treatment of Aids Steering Committee. Adherence to prescribed antiretroviral therapy in human immunodeficiency virus-infected children in the PENTA 5 trial (2003) Pediatr Infect Dis J, 22, pp. 56-62Pluciennik, A.M., (2003) Transmissão materno infantil do vírus da imunodeficiência humana adquirida: Quanto custa não prevenir [tese], , São Paulo: Faculdade de Saúde Pública da USP;Dyke, R.B.V., Lee, S., Johnson, G.M., Wiznia, A., Mohan, K., Stanley, K., Reported adherence as a determinant of response to highly active antiretroviral therapy in children who have human immunodeficiency virus infection (2002) Pediatrics, 109 (4), pp. 1-7Starace, F., Massa, A., Amico, K.R., Fisher, J.D., Adherence to antiretroviral therapy: An empirical test of the information-motivation-behavioral skills model (2006) Health Psychol, 25, pp. 153-162Shah, C.A., Adherence to high activity antiretroviral therapy (HAART) in pediatric patients infected with HIV: Issues and interventions (2007) Indian J Pediatr, 74, pp. 55-60Leite, J.C., Drachler, M.L., Centeno, M.O., Pinheiro, C.A., Silveira, V.L., Desenvolvimento de uma escala de auto-eficácia para adesão ao tratamento anti-retroviral. (2002) Psicol Reflex Crit, 15, pp. 121-133Bandura, A., Self-efficacy: Toward a unifying theory of behavioral change (1977) Psychol Rev, 84, pp. 191-215Gortmaker SL, Lenderking WR, Clark C, Lee S, Fowler MG, Oleske JMThe ACTG 219 Team. Development and use of a pediatric quality of life questionnaire in AIDS clinical trials: reliability and validity of the general health assessment for children. In: Drotar D. Measuring health-related quality of life in children and adolescents: implications for research and practice. Mahwah, NJ: Lawrence Erlbaum Associates1998. p. 219-35Eiser, C., Morse, R., Quality-of-life measures in chronic diseases of childhood (2001) Health Technol Assess, 5, pp. 1-95Streiner, D.L., Norman, G.R., (2003) Health measurement scales: A practical guide to their development and use, , 3rd ed. Oxford: Oxford University Press;Drotar D, Levi R. Critical issues and needs in health-related quality of life assessment of children and adolescents with chronic health condition. In: Drotar D. Measuring health-related quality of life in children and adolescents: implications for research and practice. Mahwah, NJ: Lawrence Erlbaum Associates1998. p. 3-2

Scaling predictions for radii of weakly bound triatomic molecules

The mean-square radii of the molecules $^4$He$_3$, $^4$He$_2-^6$Li, $^4$He$_2-^7$Li and $^4$He$_2-^{23}$Na are calculated using a three-body model with contact interactions. They are obtained from a universal scaling function calculated within a renormalized scheme for three particles interacting through pairwise Dirac-delta interaction. The root-mean-square distance between two atoms of mass $m_A$ in a triatomic molecule are estimated to be of de order of ${\cal C}\sqrt{\hbar^2/[m_A(E_3-E_2)]}$, where $E_2$ is the dimer and $E_3$ the trimer binding energies, and ${\cal C}$ is a constant (varying from $\sim 0.6$ to $\sim 1$) that depends on the ratio between $E_2$ and $E_3$. Considering previous estimates for the trimer energies, we also predict the sizes of Rubidium and Sodium trimers in atomic traps.Comment: 7 pages, 2 figure

Novel universality class of absorbing transitions with continuously varying critical exponents

The well-established universality classes of absorbing critical phenomena are directed percolation (DP) and directed Ising (DI) classes. Recently, the pair contact process with diffusion (PCPD) has been investigated extensively and claimed to exhibit a new type of critical phenomena distinct from both DP and DI classes. Noticing that the PCPD possesses a long-term memory effect, we introduce a generalized version of the PCPD (GPCPD) with a parameter controlling the memory effect. The GPCPD connects the DP fixed point to the PCPD point continuously. Monte Carlo simulations show that the GPCPD displays novel type critical phenomena which are characterized by continuously varying critical exponents. The same critical behaviors are also observed in models where two species of particles are coupled cyclically. We suggest that the long-term memory may serve as a marginal perturbation to the ordinary DP fixed point.Comment: 13 pages + 10 figures (Full paper version

Relativistic K shell decay rates and fluorescence yields for Zn, Cd and Hg

In this work we use the multiconfiguration Dirac-Fock method to calculate the transition probabilities for all possible decay channels, radiative and radiationless, of a K shell vacancy in Zn, Cd and Hg atoms. The obtained transition probabilities are then used to calculate the corresponding fluorescence yields which are compared to existing theoretical, semi-empirical and experimental results

Increased long-term mortality in women with high left ventricular ejection fraction: data from the CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) long-term registry

Aims: There are significant sex-specific differences in left ventricular ejection fraction (LVEF), with a higher LVEF being observed in women. We sought to assess the clinical relevance of an increased LVEF in women and men. Methods and results: A total of 4632 patients from the CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry (44.8% women; mean age 58.7 \ub1 13.2 years in men and 59.5 \ub1 13.3 years in women, P = 0.05), in whom LVEF was measured by cardiac computed tomography, were categorized according to LVEF (low &lt;55%, normal 55-65%, and high &gt;65%). The prevalence of high LVEF was similar in both sexes (33.5% in women and 32.5% in men, P = 0.46). After 6 years of follow-up, no difference in mortality was observed in patients with high LVEF in the overall cohort (P = 0.41). When data were stratified by sex, women with high LVEF died more often from any cause as compared to women with normal LVEF (8.6% vs. 7.1%, log rank P = 0.032), while an opposite trend was observed in men (5.8% vs. 6.8% in normal LVEF, log rank P = 0.89). Accordingly, a first order interaction term of male sex and high LVEF was significant (hazard ratios 0.63, 95% confidence intervals 0.41-0.98, P = 0.043) in a Cox regression model of all-cause mortality adjusted for age, cardiovascular risk factors, and severity of coronary artery disease (CAD). Conclusion: Increased LVEF is highly prevalent in patients referred for evaluation of CAD and is associated with an increased risk of death in women, but not in men. Differentiating between normal and hyperdynamic left ventricles might improve risk stratification in women with CAD