Lattice Model for water-solute mixtures

A lattice model for the study of mixtures of associating liquids is proposed. Solvent and solute are modeled by adapting the associating lattice gas (ALG) model. The nature of interaction solute/solvent is controlled by tuning the energy interactions between the patches of ALG model. We have studied three set of parameters, resulting on, hydrophilic, inert and hydrophobic interactions. Extensive Monte Carlo simulations were carried out and the behavior of pure components and the excess properties of the mixtures have been studied. The pure components: water (solvent) and solute, have quite similar phase diagrams, presenting: gas, low density liquid, and high density liquid phases. In the case of solute, the regions of coexistence are substantially reduced when compared with both the water and the standard ALG models. A numerical procedure has been developed in order to attain series of results at constant pressure from simulations of the lattice gas model in the grand canonical ensemble. The excess properties of the mixtures: volume and enthalpy as the function of the solute fraction have been studied for different interaction parameters of the model. Our model is able to reproduce qualitatively well the excess volume and enthalpy for different aqueous solutions. For the hydrophilic case, we show that the model is able to reproduce the excess volume and enthalpy of mixtures of small alcohols and amines. The inert case reproduces the behavior of large alcohols such as, propanol, butanol and pentanol. For last case (hydrophobic), the excess properties reproduce the behavior of ionic liquids in aqueous solution.Comment: 28 pages, 13 figure

Single dose cold blood cardioplegia inadult patients : rationale and technique description

1-4Different cardioplegia techniques and strategies have demonstrated to be safe and useful in cardiac surgery. After having employed a series of strategies and according to results published by others and us, ease of use and hospital costs we devised a single dose blood cold cardioplegia strategy. Based on observations and the rationale for the use of blood, crystalloid, cold and warm cardioplegia, we have modified a blood-based cardioplegia to be delivered in a hypothermic single dose strategy with a minimum addition of substrates using each patient´s own blood which results in a simple, low cost technique

Profiling of a high mannose-type N-glycosylated lipase using hydrophilic interaction chromatography-mass spectrometry

Many industrial enzymes exhibit macro- and micro-heterogeneity due to co-occurring post-translational modifications. The resulting proteoforms may have different activity and stability and, therefore, the characterization of their distributions is of interest in the development and monitoring of enzyme products. Protein glycosylation may play a critical role as it can influence the expression, physical and biochemical properties of an enzyme. We report the use of hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS) to profile intact glycoform distributions of high mannose-type N-glycosylated proteins, using an industrially produced fungal lipase for the food industry as an example. We compared these results with conventional reversed phase LC-MS (RPLC-MS) and sodium dodecyl sulfate-polyacrylamide gel-electrophoresis (SDS-PAGE). HILIC appeared superior in resolving lipase heterogeneity, facilitating mass assignment of N-glycoforms and sequence variants. In order to understand the glycoform selectivity provided by HILIC, fractions from the four main HILIC elution bands for lipase were taken and subjected to SDS-PAGE and bottom-up proteomic analysis. These analyses enabled the identification of the most abundant glycosylation sites present in each fraction and corroborated the capacity of HILIC to separate protein glycoforms based on the number of glycosylation sites occupied. Compared to RPLC-MS, HILIC-MS reducted the sample complexity delivered to the mass spectrometer, facilitating the assignment of the masses of glycoforms and sequence variants as well as increasing the number of glycoforms detected (69 more proteoforms, 177% increase). The HILIC-MS method required relatively short analysis time (<30 min), in which over 100 glycoforms were distinguished. We suggest that HILIC(-MS) can be a valuable tool in characterizing bioengineering processes aimed at steering protein glycoform expression as well as to check the consistency of product batche

Jogo de rol como teste informatizado para avaliar a resolução de conflitos na infância

This paper presents the results from developing an online role-playing game based on simulated situations for assessing the resolutions of conflicts in childhood. We compare the answers provided by two groups of children who answered the computer game test and the board game version with the presence of an interviewer. The results indicate that children who answered the computer-based test were more inclined to attack, than those who answered the board game version. As a conclusion, we can state that the decisions children made in the different situations varied according to a greater or lesser expectation of social sanction when answering the questions. In this way, the use of computer-based tests and simulated situations may help to study spontaneous responses that reflect everyday behaviorSe presentan los resultados del desarrollo de un videojuego online como test informatizado basado en situaciones simuladas para acceder a la resolución de conflictos en la infancia. Comparamos las respuestas dadas por dos grupos de niños quienes respondieron la versión del juego de computador y la versión del juego de mesa con presencia de un entrevistador. Como conclusión se pudo establecer que las decisiones que los niños toman en las distintas situaciones varían de acuerdo a una mayor o menor expectativa de sanción social al responder las preguntas. En este sentido, el uso de test informatizados y la simulación de situaciones podría ayudar a estudiar respuestas más espontáneas que reflejen comportamientos cotidianosEste trabalho apresenta os resultados do desenvolvimento de um videogame online como uma prova computadorizada baseado em situações simuladas para acessar a resolução de conflitos na infância. Comparamos as respostas dadas por dois grupos de crianças que responderam à versão do jogo de computador e à versão do jogo de tabuleiro com a presença de um entrevistador. Como conclusão, foi estabelecido que as decisões que as crianças fazem em diferentes situações variam de acordo com uma maior ou menor expectativa de sanção social ao responder as perguntas. Nesse sentido, o uso de testes computadorizados e a simulação de situações podem ajudar a estudar respostas mais espontâneas que refletem os comportamentos diários das crianças

Adaptation, reliability and validity of a Brief Multicomponent AIDS Phobia Scale (MAPS) in Colombian adolescents

La fobia al sida consiste en un miedo persistente, anormal e injustificado a contraer el VIH. Uno de los instrumentos disponibles para evaluar la fobia al sida es la Multicomponent AIDS Phobia Scale (MAPS). El objetivo de este estudio fue adaptar y validar la MAPS en adolescentes colombianos. Participaron 859 estudiantes entre 14-19 años respondiendo a la MAPS y otros autoinformes para analizar su validez (conocimientos sobre las ITS, actitud hacia el VIH y ansiedad por la salud). El análisis factorial confirmó la estructura bifactorial (F1: miedo a la infección y F2: miedo a otros), de acuerdo con la versión original. Se obtuvo evidencias de fiabilidad y validez consistentes con la teoría. La aplicación de la MAPS es idónea para evaluar miedo al VIH/sida y estudiar su relación con factores de riesgo sexual (uso de condón, múltiples parejas sexuales) a nivel investigador y comunitario en Colombia. También puede ser útil para evaluar el impacto de campañas sociales para reducir el estigma hacia el VIH y programas de prevención dirigidos a promover una sexualidad saludable en adolescentes mediante la transmisión de conocimientos adecuados y actitudes más tolerantes hacia las personas que viven con VIH.The AIDS phobia is a persistent, abnormal and unjustified fear of contracting HIV. The objective of this study was to adapt and validate MAPS in Colombian adolescents. Participants included 856 students aged 14-19 years who responded to the MAPS and other self-reports to analyze its validity (including knowledge about STIs, attitude towards HIV and health anxiety). Factor analysis confirmed the bifactorial structure (F1: fear of infection and F2: fear of others), according to the original version. Evidence of reliability and validity was obtained consistently with the theory. The application of MAPS is appropriate for assessing fear of HIV/AIDS and to study its relationship with sexual risk factors (e.g. condom use, multiple sexual partners) at research and community levels in Colombia. It also can be useful for assessing the impact of social campaigns to reduce stigma towards HIV and prevention programs aimed at promoting healthy sexuality in adolescents through the transmission of adequate knowledge and more favorable attitudes toward people living with HI

Does native Trypanosoma cruzi calreticulin mediate growth inhibition of a mammary tumor during infection?

Indexación: Web of Science.Background: For several decades now an antagonism between Trypanosoma cruzi infection and tumor development has been detected. The molecular basis of this phenomenon remained basically unknown until our proposal that T. cruzi Calreticulin (TcCRT), an endoplasmic reticulum-resident chaperone, translocated-externalized by the parasite, may mediate at least an important part of this effect. Thus, recombinant TcCRT (rTcCRT) has important in vivo antiangiogenic and antitumor activities. However, the relevant question whether the in vivo antitumor effect of T. cruzi infection is indeed mediated by the native chaperone (nTcCRT), remains open. Herein, by using specific modified anti-rTcCRT antibodies (Abs), we have neutralized the antitumor activity of T. cruzi infection and extracts thereof, thus identifying nTcCRT as a valid mediator of this effect. Methods: Polyclonal anti-rTcCRT F(ab')(2) Ab fragments were used to reverse the capacity of rTcCRT to inhibit EAhy926 endothelial cell (EC) proliferation, as detected by BrdU uptake. Using these F(ab')(2) fragments, we also challenged the capacity of nTcCRT, during T. cruzi infection, to inhibit the growth of an aggressive mammary adenocarcinoma cell line (TA3-MTXR) in mice. Moreover, we determined the capacity of anti-rTcCRT Abs to reverse the antitumor effect of an epimastigote extract (EE). Finally, the effects of these treatments on tumor histology were evaluated. Results: The rTcCRT capacity to inhibit ECs proliferation was reversed by anti-rTcCRT F(ab')(2) Ab fragments, thus defining them as valid probes to interfere in vivo with this important TcCRT function. Consequently, during infection, these Ab fragments also reversed the in vivo experimental mammary tumor growth. Moreover, anti-rTcCRT Abs also neutralized the antitumor effect of an EE, again identifying the chaperone protein as an important mediator of this anti mammary tumor effect. Finally, as determined by conventional histological parameters, in infected animals and in those treated with EE, less invasive tumors were observed while, as expected, treatment with F(ab')(2) Ab fragments increased malignancy. Conclusion: We have identified translocated/externalized nTcCRT as responsible for at least an important part of the anti mammary tumor effect of the chaperone observed during experimental infections with T. cruzi.http://bmccancer.biomedcentral.com/articles/10.1186/s12885-016-2764-

Random graphs with arbitrary degree distributions and their applications

Recent work on the structure of social networks and the internet has focussed attention on graphs with distributions of vertex degree that are significantly different from the Poisson degree distributions that have been widely studied in the past. In this paper we develop in detail the theory of random graphs with arbitrary degree distributions. In addition to simple undirected, unipartite graphs, we examine the properties of directed and bipartite graphs. Among other results, we derive exact expressions for the position of the phase transition at which a giant component first forms, the mean component size, the size of the giant component if there is one, the mean number of vertices a certain distance away from a randomly chosen vertex, and the average vertex-vertex distance within a graph. We apply our theory to some real-world graphs, including the world-wide web and collaboration graphs of scientists and Fortune 1000 company directors. We demonstrate that in some cases random graphs with appropriate distributions of vertex degree predict with surprising accuracy the behavior of the real world, while in others there is a measurable discrepancy between theory and reality, perhaps indicating the presence of additional social structure in the network that is not captured by the random graph.Comment: 19 pages, 11 figures, some new material added in this version along with minor updates and correction

Electron Capture Dissociation Mass Spectrometry of Tyrosine Nitrated Peptides

In vivo protein nitration is associated with many disease conditions that involve oxidative stress and inflammatory response. The modification involves addition of a nitro group at the position ortho to the phenol group of tyrosine to give 3-nitrotyrosine. To understand the mechanisms and consequences of protein nitration, it is necessary to develop methods for identification of nitrotyrosine-containing proteins and localization of the sites of modification.Here, we have investigated the electron capture dissociation (ECD) and collision-induced association (CID) behavior of 3-nitrotyrosine-containing peptides. The presence of nitration did not affect the CID behavior of the peptides. For the doubly-charged peptides, addition of nitration severely inhibited the production of ECD sequence fragments. However, ECD of the triply-charged nitrated peptides resulted in some singly-charged sequence fragments. ECD of the nitrated peptides is characterized by multiple losses of small neutral species including hydroxyl radicals, water and ammonia. The origin of the neutral losses has been investigated by use of activated ion (AI) ECD. Loss of ammonia appears to be the result of non-covalent interactions between the nitro group and protonated lysine side-chains

ANÁLISIS DE INSTRUMENTOS DE MEDICIÓN DEL PENSAMIENTO CRÍTICO

Critical thinking is a relevant ability nowadays in higher education, but there is a lack of consensus on its definitions and assessment instruments. This article offers a conceptual and methodological review about the instruments used to measure critical thinking, in order to generate a discussion that allows a better understanding and appreciation of the aspects that are considered in this skill. The methodology consisted of a systematic review of studies in databases, selecting 31 studies out of 97 founded, and 8 of them for deep analysis; atopic content analysis in definitions and test characteristics is also used. Results show the existence of many differences in definitions and assessments of critical thinking, with a variety of tests and little consensus on the measured components. The need of an integrative model of Critical Thinking, considering cognitive, metacognitive and dispositional skills is discussed.El pensamiento crítico es una competencia relevante hoy en día en la formación universitaria, con escaso consenso conceptual y metodológico en sus instrumentos de medición. En este artículo se ofrece una revisión acerca de los instrumentos que se han utilizado para medir el pensamiento crítico, con la finalidad de generar una discusión que permita una mejor comprensión y valoración de los aspectos que componen esta habilidad. La metodología utilizada consiste en una revisión sistemática de estudios en bases de datos, seleccionando 31 estudios de 97 encontrados, y analizando en profundidad ocho de ellos; se utilizó además, análisis de contenido temático para las definiciones y características de instrumentos. Los resultados señalan la existencia de divergencias a la hora de definir y evaluar el pensamiento crítico, con variedad de instrumentos y escaso consenso en los componentes medidos. Se discute la necesidad de lograr un modelo de Pensamiento Crítico integrado que considere habilidades cognitivas, metacognitivas y disposicionales