Influence of apical enlargement in cleaning and extrusion in canals with mild and moderate curvatures

Optical microscopy and morphometric analysis were used in this study to evaluate, in vitro, the cleaning of the apical region in root canals with mild or moderate curvatures subjected to biomechanical preparation with a rotary system, as well as to assess the amount of extruded material to the periapical area. Lateral incisors (n = 32), 16 with curvature angles smaller or equal to 10° (GI) and 16 between 11° and 25° angles (GII) were submitted to Hero 642 rotary instrumentation with different surgical diameters: (A) 30.02 and (B) 45.02. Irrigation was performed at each change of instrument with 5 mL of ultrapure Milli-Q water and the extruded material through the apical foramen was collected. Root cross-sections were subjected to histological analysis by optical microscopy (×40) and the images were evaluated morphometrically using the Image Tool software. Quantification of the extruded material was performed by weighing after liquid evaporation. ANOVA showed no statistically significant differences (p>0.05) among the groups with respect to the procedures used to clean the apical region. Considering the amount of extruded material, the Tukey's HSD showed that canals with mild curvature prepared with the 45.02 surgical diameter showed significantly higher values (p<0.05) that those of the other groups, which were similar between themselves (p>0.05). In conclusion, the effect of cleaning the apical region did not differ in the groups, considering root curvature and the surgical diameter of instruments used for apical preparation. The amount of extruded material was greater in canals with mild curvature that were prepared with the 45.02 surgical instrument diameter.

Las tecnologías de la información y de las comunicaciones (TIC) y el desarrollo sostenible en América Latina y el Caribe: experiencias e iniciativas de política. Memoria del seminario realizado en la CEPAL Santiago, 22 y 23 de octubre de 2012

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Informe de la VII Reunion del Consejo Directivo de CELADE celebrada del 22 al 23 de Abril de 1974

Este documento desarrolla el temario de la VII Reunion del Consejo Directivo del CELADE realizada en Abril de 1974. Previa presentacion del Informe de la VI Reunion del Consejo, se detalla el informe de administracion y de actividades correspondientes a 1973 y el programa de trabajo y presupuesto para 1974-1975, discutiendose asimismo la reestructuracion institucional del Centro y las perspectivas a mediano plazo

Psychosocial factors for risk and protection to child malnutrition in mothers of malnourished and eutrophic children: the role of maternal mental health

In this study, the relationship between child malnutrition, depression, anxiety and other maternal socio-demographic variables was investigated in mothers of malnourished (MD) and eutrophic (ME) children. The causes attributed by mothers to malnutrition were also studied. Ten mothers from each group, with children aged from 11 months to three years and who were users of primary health care units, participated in the study. They answered Beck depression and anxiety inventory, a questionnaire on vital events and an open question concerning the causes of malnutrition. The evaluation instruments were corrected according to proper guidelines and comparative analyses between the groups were performed. The answers to the open question were qualitatively evaluated, submitted to content analysis. The mothers in the two groups were nearly 30 years old or older. They had a steady partner and were subject to very similar life conditions. They had attended school for 5.5 years and were housewives or worked in low-income jobs. Concerning mental health indicators, a significantly larger number of mothers in the MM group showed depression indicators when compared to mothers in the EM group. Most mothers attributed malnutrition to biological factors or to the lack of maternal care, with more moralist statements in the EM group, and statements filled with guilt in MM. Results suggest that in order to fight malnutrition, in addition to nutritional interventions, it is necessary to heed attention to maternal socio-emotional issues.

Sensor for diuron quantitation based on the P450 biomimetic catalyst nickel(II) 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine

A biomimetic sensor based on a carbon paste electrode modified with the nickel(II) 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine complex was developed as a reliable alternative technique for the sensitive and selective analysis of the herbicide diuron in environmental media. The sensor was evaluated using cyclic voltammetry and amperometric techniques. The best amperometric responses were obtained at 750 mV vs. Ag/AgCl (KClsat), using 0.1 mol L-1 phosphate buffer solution at pH 8.0. Under these conditions, the sensor showed a linear response for diuron concentrations between 9.9 × 10-6 and 1.5 × 10-4 mol L -1, a sensitivity of 22817 (±261) μA L mol-1, and detection and quantification limits of 6.14 × 10-6 and 2 × 10-5 mol L-1, respectively. The presence of the nickel complex in the carbon paste improved selectivity, stability, and sensitivity (which increased 700%), compared to unmodified paste. The applicability of the sensor was demonstrated using enriched environmental samples (river water and soil). © 2012 Elsevier B.V. All rights reserved.

Effect of Ag addition on phase transitions of the Cu-22.26 at.%Al-9.93 at.%Mn alloy

The phase transitions that occur in the Cu-22.26 at.%Al-9.93 at.%Mn and Cu-22.49 at.%Al-10.01 at.%Mn-1.53 at.%Ag alloys after slow cooling were studied using differential scanning calorimetry at different heating rates, microhardness changes with temperature, magnetization changes with temperature, scanning electron microscopy and energy dispersion X-ray spectroscopy. The results indicated that the presence of Ag does not modify the transition sequence of Cu-Al-Mn alloy, introduces a new transition due to the (Ag-Cu)-rich precipitates dissolution at about 800 K, and changes the mechanism of DO 3 phase dissolution. This mechanistic change was analyzed and a sequence of phase transitions was proposed for the reaction. © 2013 Elsevier B.V.

Acta resumida de la 77a sesión celebrada en Panamá el viernes 22 de mayo de 1959 a las 16.55 horas

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