Stereological Evaluation of Precipitates within Ferrite Grains in Heat-Treated 1.25Cr0.5Mo Steel Previously Exposed to Service

The objective of this work was to study the effect of the heat treatment and further operation aging on the stereological parameters (size, quantity and volume fraction) of precipitates within ferrite grains of a creep-resistant 1.25Cr0.5Mo steel after long-term operation. The heat treatment was similar to the treatment that is carried out in industrial steam pipelines after welding (post weld heat treatment - PWHT) during installation and/or repairing. The operation aging corresponds to a subsequent long in-service operation after repairing. To determine the stereological parameters, SEM digital images were taken from samples of this material after conditions of in-service-aged (after long-term operation), in-service-aged and heat-treated (simulating repairing) and in-service-aged, heat-treated and in-laboratory aged (simulating subsequent long-term operation after repairing). The results indicate that the changes in the stereological parameters of the precipitates within ferrite grains after PWHT is associated with the coarsening process of the within-ferrite-grain precipitates as well as stabilizing the microstructure, since the material aging after PWHT of an in-serviced aged material would not change the stereological parameters

Model of macroeconomic evolution in stable regionally dependent economic fields

We develop a model for the evolution of economic entities within a geographical type of framework. On a square symmetry lattice made of three (economic) regions, firms, described by a scalar fitness, are allowed to move, adapt, merge or create spin-offs under predetermined rules, in a space and time dependent economic environment. We only consider here one timely variation of the ''external economic field condition''. For the firm fitness evolution we take into account a constraint such that the disappearance of a firm modifies the fitness of nearest neighboring ones, as in Bak-Sneppen population fitness evolution model. The concentration of firms, the averaged fitness, the regional distribution of firms, and fitness for different time moments, the number of collapsed, merged and new firms as a function of time have been recorded and are discussed. Also the asymptotic values of the number of firms present in the three regions together with their average fitness, as well as the number of respective births and collapses in the three regions are examined. It appears that a sort of $critical$ selection pressure exists. A power law dependence, signature of self-critical organization is seen in the birth and collapse asymptotic values for a high selection pressure only. A lack of self-organization is also seen at region borders.Comment: 11 figures double columns on 7 page

Tumor de células da granulosa do ovário: estudo de casos com utilização da imuno-histoquímica no diagnóstico diferencial

Um estudo retrospectivo de 23 casos de tumor de células da granulosa do ovário foi realizado. Inicialmente foi feito um estudo imuno-histoquímico empregando anticorpos antiantígeno de membrana epitelial e citoceratina. Nenhum tumor com histologia característica mostrou positividade para estes anticorpos, enquanto três com histologia não característica apresentaram reações positivas. Estes tumores foram classificados como tumores epiteliais indiferenciados, pois tanto o prognóstico desfavorável como a baixa taxa de sobrevida indicavam não se tratar de tumor de células da granulosa. Os autores prosseguiram o estudo clínico e anatomo-patológico somente com os casos que confirmaram, pela histologia e imuno-histoquímica, ser tumor de células da granulosa. A dor abdominal foi o sintoma mais frequente e somente. 50% apresentaram sintomas ligados à ação estrogênica. Características histológicas não diferiram das Já relatadas. Não se evidenciou o tamanho do tumor como fator prognóstico. Dos 12 casos em que foi realizada avaliação do endométrio, o achado de hiperplasia foi o mais comum. O tratamento cirúrgico foi o de escolha como conduta iniciai O tratamento adjuvante ou complementar foi discutido

Caracterización tecnológica de una arcilla utilizada en la fabricación de productos de mampostería para la construcción

In the present investigation, the physical, mechanical, and chemical characterization of the raw material used in two companies dedicated to the manufacture of solid bricks in the region of Cesar, Colombia, was carried out. Initially, the hydrometric test was performed on five clay samples from different quarries with which the percentages of sand, silt, and clays were determined. These percentages were placed in the Winkler diagram to identify the types of existing clays according to their texture and the types of products that can be manufactured. Subsequently, the chemical characterization was carried out through the X-ray diffraction and fluorescence tests, to determine the phases and elements present in two of the optimal samples for the manufacture of the bricks that may arise during the cooking process. The results of the test of mechanical resistance to compression in solid brick units showed that the clays currently used by the company do not meet the minimum requirements for the production of solid clay bricks, according to the parameters of the Colombian technical standard NTC 4205-09. With this research, we expect to predict the behavior of the raw material in the stages of the production process, which will obviously improve the environmental and economic resources of the companies. The result of the characterization of the raw material will allow us to predict the structural behavior and to carry out indispensable design and reinforcement models in building and attention to the community.En la presente investigación se llevó a cabo la caracterización física, mecánica y química de la materia prima utilizada en dos empresas dedicadas a la fabricación de ladrillos macizos en la región del Cesar, Colombia. Inicialmente, se llevó a cabo el ensayo de hidrometría a cinco muestras de arcilla de diferentes canteras con los cuales se determinaron los porcentajes de arenas, limos y arcillas. Estos porcentajes fueron ubicados en el diagrama de Winkler para identificar los tipos de arcillas existentes según su textura y los tipos de productos que se pueden fabricar. Posteriormente, se realizó la caracterización química a través de las pruebas de difracción y fluorescencia de rayos X, con la finalidad de determinar las fases y elementos presentes en dos de las muestras óptimas para la fabricación de los ladrillos que pueden surgir durante el proceso de cocción. Los resultados del ensayo de resistencia mecánica a la compresión en unidades de ladrillo macizo, demostraron que las arcillas utilizadas actualmente por la empresa no cumplen los requerimientos mínimos para la elaboración de ladrillos de arcilla macizo, acorde a los parámetros de la norma técnica Colombiana NTC 4205-09. Con esta investigación se espera poder pronosticar el comportamiento de la materia prima en las etapas del proceso productivo, con lo que evidentemente se mejoraran los recursos ambientales y económicos de las empresas. Resultado de la caracterización de la materia prima permitirá predecir el comportamiento estructural, y realizar modelos de diseño y reforzamiento en edificación indispensables y de atención a la comunidad

Gastric cancer in patients attending the digestive endoscopy service

Introduction: gastric cancer for many countries in the world and in Cuba is a major health problem. Objective: to determine the clinical-epidemiological characteristics of patients diagnosed with gastric cancer in the digestive endoscopy service at Abel Santamaría Cuadrado General Teaching Hospital. Method: a descriptive, cross-sectional study of 39 patients with suggestive and endoscopic symptoms of gastric cancer, and the sample included 36 patients with positive histology. The variables taken were: age, sex, and histology of the gastric biopsy, result of the upper digestive endoscopy, associated risk factors, clinical manifestations and metastasis. Frequency distribution analysis was used. Results: the most affected group was 61 to 70 years old, being more frequent in male sex, with epigastralgia in 55.5% as the main symptom, the ulcerated form was the most observed localized in antrum and pylorus, intestinal type of adenocarcinoma was the most frequent in the histological assessment, Helicobacter pylori infection was present in 63.8% of the cases as a predominant risk factor, with metastases findings in the 69.4% of all cases of the estudied universe. Conclusion: most of the cases were diagnosed in advanced stages, when the probability of cure is reduced

Divergent mathematical treatments in utility theory

In this paper I study how divergent mathematical treatments affect mathematical modelling, with a special focus on utility theory. In particular I examine recent work on the ranking of information states and the discounting of future utilities, in order to show how, by replacing the standard analytical treatment of the models involved with one based on the framework of Nonstandard Analysis, diametrically opposite results are obtained. In both cases, the choice between the standard and nonstandard treatment amounts to a selection of set-theoretical parameters that cannot be made on purely empirical grounds. The analysis of this phenomenon gives rise to a simple logical account of the relativity of impossibility theorems in economic theory, which concludes the paper

Cáncer gástrico en pacientes atendidos en servicio de endoscopia digestiva

Introduction: gastric cancer for many countries in the world and in Cuba is a major health problem.Objective: to determine the clinical-epidemiological characteristics of patients diagnosed with gastric cancer in the digestive endoscopy service at Abel Santamaría Cuadrado General Teaching Hospital.Method: a descriptive, cross-sectional study of 39 patients with suggestive and endoscopic symptoms of gastric cancer, and the sample included 36 patients with positive histology. The variables taken were: age, sex, and histology of the gastric biopsy, result of the upper digestive endoscopy, associated risk factors, clinical manifestations and metastasis. Frequency distribution analysis was used.Results: the most affected group was 61 to 70 years old, being more frequent in male sex, with epigastralgia in 55.5% as the main symptom, the ulcerated form was the most observed localized in antrum and pylorus, intestinal type of adenocarcinoma was the most frequent in the histological assessment, Helicobacter pylori infection was present in 63.8% of the cases as a predominant risk factor, with metastases findings in the 69.4% of all cases of the estudied universe.Conclusion: most of the cases were diagnosed in advanced stages, when the probability of cure is reduced.Introducción: el cáncer gástrico para muchos países del mundo y Cuba es un gran problema de salud.Objetivo: determinar las características clínico- epidemiológico de los pacientes diagnosticados de cáncer gástrico en el servicio de endoscopia digestiva del Hospital General Docente Abel Santamaría Cuadrado. Método: estudio descriptivo, transversal, conformaron el universo 39 pacientes con sintomatología y endoscopia sugestiva de cáncer gástrico, y la muestra los 36 pacientes con histología positiva. Variables edad, sexo, histología de la biopsia gástrica, resultado de la endoscopia digestiva superior, factores de riesgo asociados, manifestaciones clínicas y metástasis. Se utilizó el análisis de distribución de frecuencias.Resultados: el grupo etario más afectado fue el de 61 a 70 años, siendo más frecuente en el sexo masculino, con epigastralgia en el 55,5 % como síntoma principal, la forma ulcerada fue la más observada localizándose en antro y píloro, el adenocarcinoma tipo intestinal fue el de mayor frecuencia histológica, con infección por Helicobater pylori en el 63,8% de los casos como factor de riesgo predominante, con hallazgo de metástasis en el 69,4 % de todo el universo estudiado.Conclusiones: la mayoría de los casos se diagnosticaron en etapas avanzadas, cuando la probabilidad de curación es muy reducida

New primers for promising single-copy genes in fungal phylogenetics and systematics

Developing powerful phylogenetic markers is a key concern in fungal phylogenetics. Here we report degenerate primers that amplify the single-copy genes Mcm7 (MS456) and Tsr1 (MS277) across a wide range of Pezizomycotina (Ascomycota). Phylogenetic analyses of 59 taxa belonging to the Eurotiomycetes, Lecanoromycetes, Leotiomycetes, Lichinomycetes and Sordariomycetes, indicate the utility of these loci for fungal phylogenetics at taxonomic levels ranging from genus to class. We also tested the new primers in silico using sequences of Saccharomycotina, Taphrinomycotina and Basidiomycota to predict their potential of amplifying widely across the Fungi. The analyses suggest that the new primers will need no, or only minor sequence modifications to amplify Saccharomycotina, Taphrinomycotina and Basidiomycota

A randomised trial of subcutaneous intermittent interleukin-2 without antiretroviral therapy in HIV-infected patients: the UK-Vanguard Study

Objective: The objective of the trial was to evaluate in a pilot setting the safety and efficacy of interleukin-2 (IL-2) therapy when used without concomitant antiretroviral therapy as a treatment for HIV infection. Design and Setting: This was a multicentre randomised three-arm trial conducted between September 1998 and March 2001 at three clinical centres in the United Kingdom. Participants: Participants were 36 antiretroviral treatment naive HIV-1-infected patients with baseline CD4 T lymphocyte counts of at least 350 cells/mm(3). Interventions: Participants were randomly assigned to receive IL-2 at 15 million international units (MIU) per day ( 12 participants) or 9 MIU/day ( 12 participants) or no treatment ( 12 participants). IL-2 was administered by twice-daily subcutaneous injections for five consecutive days every 8 wk. Outcome Measures: Primary outcome was the change from baseline CD4 T lymphocyte count at 24 wk. Safety and plasma HIV RNA levels were also monitored every 4 wk through 24 wk. The two IL-2 dose groups were combined for the primary analysis. Results: Area under curve (AUC) for change in the mean CD4 T lymphocyte count through 24 wk was 129 cells/mm(3) for those assigned IL-2 ( both dose groups combined) and 13 cells/mm(3) for control participants (95% CI for difference, 51.3 - 181.2 cells/mm(3); p = 0.0009). Compared to the control group, significant increases in CD4 cell count were observed for both IL-2 dose groups: 104.2/mm(3) ( p = 0.008) and 128.4 cells/mm(3) ( p = 0.002) for the 4.5 and 7.5 MIU dose groups, respectively. There were no significant differences between the IL-2 (0.13 log(10) copies/ ml) and control (0.09 log(10) copies/ml) groups for AUC of change in plasma HIV RNA over the 24-wk period of follow- up ( 95% CI for difference, - 0.17 to 0.26; p = 0.70). Grade 4 and dose-limiting side effects were in keeping with those previously reported for IL-2 therapy. Conclusions: In participants with HIV infection and baseline CD4 T lymphocyte counts of at least 350 cells/mm(3), intermittent subcutaneous IL-2 without concomitant antiretroviral therapy was well tolerated and produced significant increases in CD4 T lymphocyte counts and did not adversely affect plasma HIV RNA levels