José Miguel Contreras García

Rationale and study design for an individualized perioperative open lung ventilatory strategy (iPROVE): study protocol for a randomized controlled trial

BackgroundPostoperative pulmonary and non-pulmonary complications are common problems that increase morbidity and mortality in surgical patients, even though the incidence has decreased with the increased use of protective lung ventilation strategies. Previous trials have focused on standard strategies in the intraoperative or postoperative period, but without personalizing these strategies to suit the needs of each individual patient and without considering both these periods as a global perioperative lung-protective approach. The trial presented here aims at comparing postoperative complications when using an individualized ventilatory management strategy in the intraoperative and immediate postoperative periods with those when using a standard protective ventilation strategy in patients scheduled for major abdominal surgery.MethodsThis is a comparative, prospective, multicenter, randomized, and controlled, four-arm trial that will include 1012 patients with an intermediate or high risk for postoperative pulmonary complications. The patients will be divided into four groups: (1) individualized perioperative group: intra- and postoperative individualized strategy; (2) intraoperative individualized strategy + postoperative continuous positive airway pressure (CPAP); (3) intraoperative standard ventilation + postoperative CPAP; (4) intra- and postoperative standard strategy (conventional strategy). The primary outcome is a composite analysis of postoperative complications.DiscussionThe Individualized Perioperative Open-lung Ventilatory Strategy (iPROVE) is the first multicenter, randomized, and controlled trial to investigate whether an individualized perioperative approach prevents postoperative pulmonary complications.Trial registrationRegistered on 5 June 2014 with identification no. NCT02158923.

Dynamic reorganization of the alkaline phosphatase-containing compartment during chemotactic peptide stimulation of human neutrophils imaged by backscattered electrons

Scanning electron microscopy (EM) and cytochemical techniques were used to examine the alkaline phosphatase-containing compartment in human neutrophils after stimulation with nanomolar concentrations of N-formylmethionyl-leucyl-phenylalanine (10−8M fMLP). Alkaline phosphatase (AlkPase) activity was demonstrated with a lead-based metal capture cytochemical method. The reaction product was visualized with the backscattered electron imaging mode of scanning EM, and analyzed by electron probe X-ray microanalysis. Alkaline phosphatase activity was detected only in fMLP-stimulated neutrophils; unstimulated neutrophils displayed no activity. Stimulation of human neutrophils with 10−8 M fMLP induced a time-dependent intracellular redistribution of irregular round or tubular granules containing alkaline phosphatase activity, as seen by backscattering. The intracellular redistribution of alkaline phosphatase activity was accompanied by increased cytochemical activity on the cell surface. The reaction product was localized preferentially on ridges and folds of polar neutrophils. Reorganization of the AlkPase-containing compartment correlated with changes induced by fMLP in cell shape, ie, membrane ruffling and front-tail polarity, as observed with the secondary electron image mode of scanning EM. These findings demonstrate the intracellular reorganization, increase, and asymmetric distribution of alkaline phosphatase activity on the plasma membrane of human neutrophils after stimulation by chemotactic peptides.

Distribution pattern of acid phosphatase activity in human peripheral blood leukocytes: a cytochemical scanning electron microscopy study

SummaryThe distribution patterns of acid phosphatase hydrolytic activity were studied in human peripheral blood cells with enzymocytochemical techniques together with light and scanning electron microscopy in the secondary and backscattered electron imaging modes. The acid phosphatase reaction product was seen in three different patterns of distribution: focal, granular and diffuse. These patterns were correlated with similar findings obtained with light microscopy. Acid phosphatase distribution patterns seen with SEM in the BEI mode were also correlated with the surface morphology of peripheral blood cells seen in the SEI mode. Cells exhibiting the focal pattern were smooth-surfaced with few microvilli; cells showing a granular pattern presented microvilli and microridges; ruffles were characteristic of cells with a diffuse pattern of activity. No reaction product was seen in cells bearing microvilli or ridges. Our findings demonstrate the correlation between acid phosphatase activity patterns and surface features in different subpopulations of peripheral blood cells.

The raise estimator estimation, inference, and properties

ABSTRACT Several methods using different approaches have been developed to remedy the consequences of collinearity. To the best of our knowledge, only the raise estimator proposed by García et al. (2010) deals with this problem from a geometric perspective. This article fully develops the raise estimator for a model with two standardized explanatory variables. Inference in the raise estimator is examined, showing that it can be obtained from ordinary least squares methodology. In addition, contrary to what happens in ridge regression, the raise estimator maintains the coefficient of determination value constant. The expression of the variance inflation factor for the raise estimator is also presented. Finally, a comparative study of the raise and ridge estimators is carried out using an example.

Conocimiento matemático de profesores de primaria en formación para la enseñanza de la probabilidad: un estudio exploratorio. Doi:10.5212/PraxEduc.v.10i1.0001

Que historia, para qual cidadania? O ensino de historia na educacao basica no Mexico No Mexico a reflexao acerca dos vinculos entre a historia como disciplina escolar e os processos sociais de construcao de cidadania, requer conceber este objeto de estudo como apenas uma parte de um processo muito mais complexo que o vincula tanto a educacao civica e etica, como as praticas cotidianas conformadoras de uma certa cultura escolar. E necessario situar historicamente as origens e formas de funcionamento de cada uma dessas facetas, assim como a maneira em que entre elas se reforcam em suas pretensoes formativas. Somente desse modo e possivel reconhecer os fins, utilidades e limites do ensino de historia tal qual e concebido hoje em dia, assim como sua impossibilidade de assumir como objetivos educativos a construcao de nocoes democraticas referidas a uma concepcao moderna de cidadania. Palavras-chave: Cidadania. Historia e seu ensino. Formacao para a democracia. Resumen En Mexico la reflexion acerca de los vinculos entre la historia como disciplina escolar y los procesos sociales de construccion de ciudadania, requiere concebir este objeto de estudio como solo una parte de un proceso mucho mas complejo que lo vincula tanto a la educacion civica y etica, como a las practicas cotidianas conformadoras de una cierta cultura escolar. Es necesario ubicar historicamente los origenes y formas de funcionamiento de cada una de esas facetas, asi como la manera en que entre ellas se refuerzan en sus afanes formativos. Solo de esa forma es posible reconocer los fines, utilidades y limites de la ensenanza de la historia tal cual es concebida hoy en dia, asi como su imposibilidad de asumir como objetivos educativos la construccion de nociones democraticas referidas a una concepcion moderna de ciudadania. Palabras claves: Ciudadania. Historia y su ensenanza. Formacion para la democracia. Abstract Which history, to which citizens? History teaching in basic education in Mexico In Mexico, a reflection on the links between History as a school subject and the processes of social construction of citizenship requires conceiving the object of study as only part of a much more complex process that binds it both to civic education and ethics, and to everyday forming practices of a certain school culture. It is necessary to historically locate the sources and forms of operation of each of these facets as well as the way they reinforce their training claims.Only in this way it is possible to recognize purposes, uses and limits of teaching History as it is conceived today, as well as its inability to take as an educational goalthe building of democratic notions related to a modern conception of citizenship. Keywords: Citizenship. History and its teaching. Training for democracy.Resumen En este trabajo se evaluan algunos elementos del conocimiento matematico comun y especializado del contenido y del conocimiento del contenido y los estudiantes en relacion con la probabilidad elemental en una muestra de profesores en formacion. El conocimiento comun del contenido se evalua a partir de las soluciones de 157 profesores en formacion a tres problemas. Una vez discutidas con los participantes estas soluciones, se analizan dos componentes del conocimiento de 81 de ellos, trabajando en pequenos grupos: (a) El conocimiento especializado del contenido se evalua a partir de los contenidos matematicos identificados en los problemas; (b) el conocimiento del contenido y los estudiantes a partir de la identificacion y justificacion de respuestas de alumnos de educacion primaria. Aunque en la evaluacion inicial se observo un bajo razonamiento probabilistico, en la segunda los participantes son capaces de identificar y explicar las respuestas incorrectas de los alumnos. Palabras clave: Conocimiento Matematico para la Ensenanza. Probabilidad. Educacion Primaria. Abstract Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4 Prospective primary school teachers’ mathematical knowledge for teaching probability: an exploratory study This study assesses some elements of common and specialized mathematical knowledge and of knowledge of content and students in relation to elementary probability from a sample of prospective primary school teachers. Common knowledge of content is assessed from the individual solution of 157 prospective teachers to three problems. Once the solution to these problems was discussed with the participants, two additional components of these teachers’ mathematical knowledge for teaching were analyzed based on small group work developed by 81 participants: (1) To assess specialized knowledge of content we asked participants to identify the tasks mathematical content; (b) to assess their knowledge of content and students we asked them to identify and justify correct and incorrect answers to the problems given by primary school children. While in the initial assessment we observed a poor probabilistic reasoning, in the second part they were able to identify and explain incorrect answers given by students. Keywords: Mathematical Knowledge for Teaching. Probability. Primary School. Resumo Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4 Conhecimento m atematico de p rofessores dos anos iniciais do Ensino Fundamental em formacao para o ensino de probabilidade : u m estudo exploratorio Neste trabalho foi realizada uma avaliacao de alguns elementos do conhecimento matematico comum e especializado e do conhecimento do conteudo e os alunos sobre a probabilidade elementar de professores do ensino primario em formacao. O conhecimento comum do conteudo e avaliado a partir das solucoes de 157 professores em formacao a tres problemas. Uma vez que os participantes discutiram com estas solucoes , analisamos dois componentes do conhecimento matematico para o ensino de 81 desses alunos , trabalhando em pequenos grupos: a) O conhecimento especializado do conteudo e avaliado com base no conteudo matematico dos problemas identificados , ( b) o conhecimento do conteudo e os alunos sao avaliados com base na identificacao e justificacao das respostas de alunos do ensino fundamental . Enquanto na avaliacao inicial mostrou um raciocinio probabilistico pobre, na segunda, os participantes sao capazes de identificar e explicar as respostas incorretas dos alunos. Palavras-chave: Conhecimento matematico para o ensino. Probabilidade. Ensino Fundamental.1024x768 Este artigo visa enfatizar a necessidade, que um Programa de Pos-Graduacao em Educacao pode ter, de produzir conhecimentos, a partir de um esforco continuado de abertura a totalidade da experiencia humana, nao se fechando em posicoes epistemologicas reducionistas dessa experiencia. O artigo pontua, tambem, que a formacao de estudiosos e de profissionais da educacao tem, como tarefa principal, a consolidacao do habito intelectual de sensibilidade e de criatividade diante de qualquer manifestacao da vida humana, tal como aflora nos varios processos culturais, na diversidade e na complexidade de cada um deles, na concreticidade das praticas sociais que os engendram. Palavras-chave: Educacao. Experiencia. Significado. Abstract Meaning of knowledge production in Postgraduate studies and its communication with social practices This paper highlights the need, which a Postgraduate Programme in Education may have, of producing knowledge from a continuous effort of integral human experience openness, not closing itself to narrow epistemological positions of that experience. This paper also enphasizes that the education of scholars and education professionals has as main task the consolidation of the intellectual habit of being creative and sensitive towards any manifestation of human life, just as it emerges in various cultural processes, in the diversity and complexity of each one of them and in the reality of social practices that give birth to them. Keywords: Education. Experience. Meaning. Resumen Significados de la produccion del conocimiento en el Posgrado y en sus interlocuciones con la practica social El articulo tiene como objetivo enfatizar la necesidad, que un Programa de Posgrado en Educacion puede tener, de producir conocimientos, empezando por um esfuerzo continuado de apertura a la totalidad de la experiencia humana, sin cerrarse en posiciones epistemologicas reduccionistas acerca de esa experiencia. Enfatizar tambien que la formacion de estudiosos y profesionales de la educacion tiene, como tarea principal, la consolidacion del habito intelectual de la sensibilidad y de la creatividad, delante de cualquier manifestacion de vida humana, tal como emerge en sus varios procesos culturales; en la diversidad y complejidad de cada uno de ellos; em la concrecion de las practicas sociales que los engendran. Palabras clave: Educacion. Experiencia. Significado.