The Nuclear Outflow in NGC 2110

We present a HST/STIS spectroscopic and optical/radio imaging study of the Seyfert NGC 2110 aiming to measure the dynamics and understand the nature of the nuclear outflow in the galaxy. Previous HST studies have revealed the presence of a linear structure in the Narrow-Line Region (NLR) aligned with the radio jet. We show that this structure is strongly accelerated, probably by the jet, but is unlikely to be entrained in the jet flow. The ionisation properties of this structure are consistent with photoionisation of dusty, dense gas by the active nucleus. We present a plausible geometrical model for the NLR, bringing together various components of the nuclear environment of the galaxy. We highlight the importance of the circum-nuclear disc in determining the appearance of the emission line gas and the morphology of the jet. From the dynamics of the emission line gas, we place constraints on the accelerating mechanism of the outflow and discuss the relative importance of radio source synchrotron pressure, radio jet ram pressure and nuclear radiation pressure in accelerating the gas. While all three mechanisms can account for the energetics of the emission line gas, gravitational arguments support radio jet ram pressure as the most likely source of the outflow.Comment: 15 pages, 7 figures; accepted to MNRA

Ionization Mechanisms in Jet-Dominated Seyferts: A Detailed Case Study

For the past 10 years there has been an active debate over whether fast shocks play an important role in ionizing emission line regions in Seyfert galaxies. To investigate this claim, we have studied the Seyfert 2 galaxy Mkn 78, using HST UV/optical images and spectroscopy. Since Mkn 78 provides the archetypal jet-driven bipolar velocity field, if shocks are important anywhere they should be important in this object. Having mapped the emission line fluxes and velocity field, we first compare the ionization conditions to standard photoionization and shock models. We find coherent variations of ionization consistent with photoionization model sequences which combine optically thick and thin gas, but are inconsistent with either autoionizing shock models or photoionization models of just optically thick gas. Furthermore, we find absolutely no link between the ionization of the gas and its kinematic state, while we do find a simple decline of ionization degree with radius. We feel this object provides the strongest case to date against the importance of shock related ionization in Seyferts.Comment: 4 pages, 1 figure, to appear in the proceedings of IAU Symposium 222 "The Interplay among Black Holes, Stars and ISM in Galactic Nuclei", T. Storchi Bergmann, L.C. Ho & H.R. Schmitt, ed

Chest diameter ratios for detecting static hyperinflation in children using photogrammetry

OBJECTIVES: To develop a photogrammetric method capable of identifying increases in anteroposterior chest diameters suggestive of pulmonary hyperinflation, and to test it with both asthmatic and asthma-free children. METHODS: Two distinct study designs were used to achieve these two objectives. The first was a descriptive analysis of diameters measured at the height of the axilla and of the xiphoid on digital images of 56 children aged 8 to 12 years photographed in the orthostatic position. The second was a case-control study of (a) 19 asthmatic children in treatment for at least 12 months; and (b) 37 children free from asthma with no prior history of complaints of respiratory/allergic disease. Diameters were measured on images of the front and left side views using CorelDRAW®, and the ratio between the front and side diameters was calculated for the axillary and xiphoid measurements, providing the diameter ratios. Diameter ratios close to or greater than 1 represent geometry tending towards a cylindrical shape, typical of hyperinflation on radiographs. RESULTS: Analysis with the t test for independent samples revealed a mean diameter ratio at the sternum that was significantly greater in the group of asthmatic children (p < 0.01) than the mean for the whole sample and also than the mean for the children without asthma. CONCLUSIONS: Despite the existence of disagreement on the best instruments, methods and times for identifying hyperinflation, results indicate that a system using diameter ratios obtained by photogrammetry is a promising tool for the identification of a kinesiopathological manifestation that is known to determine air entrapment in asthma patients. Research that combines clinical data with longitudinal intrapatient follow-up will be necessary to establish the strength of the evidence found in this study.OBJETIVOS: Desenvolver um método fotogramétrico capaz de identificar aumento do diâmetro torácico anteroposterior sugestivo de hiperinsuflação pulmonar e testá-lo em crianças asmáticas e não asmáticas. MÉTODOS: Foram conduzidos dois perfis de estudos, sendo um deles a análise descritiva dos diâmetros medidos no nível axilar e xifóideo em imagens fotográficas digitais de 56 crianças, com idade entre 8 e 12 anos, na posição ortostática, e o outro, um estudo caso-controle entre: (a) 19 crianças asmáticas em tratamento há mais de 12 meses; (b) 37 crianças não asmáticas, sem histórico pregresso ou queixas de doenças respiratórias/alérgicas. Os diâmetros foram medidos nas imagens da vista anterior e lateral esquerda pelo uso do programa CorelDraw®, e a esses diâmetros aplicou-se a razão matemática de vista anterior por lateral esquerda para cada nível, gerando o índice denominado razão diametral. A razão diametral próxima ou superior à unidade expressou uma configuração geométrica tendendo ao formato cilíndrico, típico de hiperinsuflação nas imagens radiológicas. RESULTADOS: A análise pelo teste t para amostras independentes mostrou uma média significativamente maior para razão diametral do osso esterno no grupo de crianças asmáticas (p < 0,01) que no grupo como um todo e no grupo de crianças não asmáticas. CONCLUSÕES: Apesar das controvérsias sobre instrumentos, formas e momentos de identificação da presença de hiperinsuflação, os resultados são favoráveis ao sistema de razão diametral pela biofotogrametria como ferramenta promissora na identificação de uma expressão cinesiopatológica conhecida como determinante da retenção aérea na asma. Pesquisas que agreguem informações clínicas e acompanhamento longitudinal intrapacientes serão necessárias antes de estabelecer a força das evidências encontradas neste estudo.Grupo de Apoio ao Programa de Educacao Respiratoria (GAPER)Universidade Federal do Paraná Departamento de PediatriaUFPR Departamento de Pediatria Programa de Pós-Graduação em Saúde da Criança e do AdolescenteUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de OtorrinolaringologiaUNIFESP, EPM, Depto. de OtorrinolaringologiaSciEL

Experimental determination of superconducting parameters for the intermetallic perovskite superconductor ${\text {MgCNi}}_3

We have measured upper-critical-field $H_{\text c2}$, specific heat C, and tunneling spectra of the intermetallic perovskite superconductor MgCNi${}_3$ with a superconducting transition temperature $T_{\text c}\approx 7.6$ K. Based on these measurements and relevant theoretical relations, we have evaluated various superconducting parameters for this material, including the thermodynamic critical field $H_{\text c}$(0), coherence length $\xi$(0), penetration depth $\lambda$(0), lower-critical-field $H_{\text c1}$(0), and Ginsberg-Landau parameter $\kappa$(0). From the specific heat, we obtain the Debye temperature $\it \Theta_{\text D} \approx$ 280 K. We find a jump of $\Delta C/\gamma T_{\text c}$=2.3 at $T_{\text c}$ (where $\it \gamma$ is the normal state electronic specific coefficient), which is much larger than the weak coupling BCS value of 1.43. Our tunneling measurements revealed a gap feature in the tunneling spectra at $\it \Delta$ with $2\it {\Delta}/{\text k}_{\text B}T_{\text c}\approx$ 4.6, again larger than the weak-coupling value of 3.53. Both findings indicate that MgCNi$_3$ is a strong-coupling superconductor. In addition, we observed a pronounced zero-bias conductance peak (ZBCP) in the tunneling spectra. We discuss the possible physical origins of the observed ZBCP, especially in the context of the pairing symmetry of the material.Comment: 5 pages, 4 figure

Prevalence of recurrent wheezing in infants

OBJECTIVE: To identify the prevalence of recurrent wheezing in infants in the city of Curitiba, PR, Brazil. METHODS: A cross-sectional study carried out by means of administering questionnaires to the parents of infants aged 12 to 15 months attending health centers for immunization during the period between August 2005 and December 2006. This is a standardized and validated instrument consisting of questions on demographic characteristics, wheezing, respiratory infections and risk factors. At the time of the study the City Health Department had 107 health centers, 35 of which were selected by lots and distributed homogeneously across the municipal territory. RESULTS: A total of 1,364 infants (45.4%) had episodes of wheezing during their first 12 months of life, with onset at 5.5±3.1 months (mean ± standard deviation), and 678 (22.6%) had had three or more episodes. In 84.6% of the wheezing children treatment was with β2-agonists, with inhaled corticosteroids in 18.5%, oral corticosteroids in 24.3% and leukotriene receptor antagonists were used with 5.4%. The wheezing children exhibited nocturnal symptoms, intense difficulty breathing and visits to emergency services in the proportions of 58.9, 46.2 and 57.6%, respectively; 12.7% were admitted to hospital for asthma and 10.9% had had a medical diagnosis of asthma. Nocturnal symptoms, visits to emergency, severity of symptoms, hospital admissions for asthma and medical diagnoses of asthma were all more common among those who had suffered three or more crises (p < 0.001). CONCLUSIONS: There is an elevated prevalence of wheezing among the infants of Curitiba, with early onset and elevated morbidity. It is possible that these infants represent a large contingent of asthmatics.OBJETIVO: Verificar a prevalência da sibilância recorrente em lactentes na cidade de Curitiba (PR). MÉTODOS: Estudo transversal pela aplicação de questionários aos pais de lactentes, idade entre 12 e 15 meses, que procuraram unidades de saúde para imunização no período entre agosto de 2005 e dezembro de 2006. Este instrumento padronizado e validado consiste de perguntas sobre características demográficas, sibilância, infecções respiratórias e fatores de risco. Durante o período de estudo, a Secretaria Municipal de Saúde possuía 107 unidades de saúde, das quais 35 foram selecionadas por sorteio e distribuídas homogeneamente no território municipal. RESULTADOS: Um total de 1.364 lactentes (45,4%) apresentou um ou mais episódios de sibilância nos primeiros 12 meses de vida, com início aos 5,5±3,1 meses (média ± desvio padrão), e 678 (22,6%) tiveram três ou mais episódios. Utilizaram β2-agonistas, corticóides inalatórios, corticóides orais e antagonistas do receptor de leucotrienos 84,6, 18,5, 24,3 e 5,4% dos sibilantes, respectivamente. Sintomas noturnos, dificuldade intensa para respirar e visitas a emergência estiveram presente em 58,9, 46,2 e 57,6% dos lactentes que sibilaram; destes, 12,7% foram hospitalizados por asma e 10,9% tiveram diagnóstico médico de asma. Sintomas noturnos, visitas à emergência, gravidade dos sintomas, hospitalização por asma e diagnóstico médico de asma foram mais freqüentes entre os que apresentaram três ou mais crises (p < 0,001). CONCLUSÃO: A prevalência de lactentes sibilantes em Curitiba é elevada, com início precoce e alta morbidade. Possivelmente, esses lactentes representam um contingente expressivo de asmáticos.Universidade Federal do Paraná Hospital de ClínicasUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade de Santiago do ChileUNIFESP, EPMSciEL