Invariant Sets and Explicit Solutions to a Third-Order Model for the Shearless Stratified Turbulent Flow

We study dynamics of the shearless stratified turbulent flows. Using the method of differential constraints we find a class of explicit solutions to the problem under consideration and establish that the differential constraint obtained coincides with the well-known Zeman--Lumley model for stratified flows.Comment: arxiv version is already officia

Comunicación y accesibilidad en sitios web municipales de la región del nordeste argentino, su evaluación mediante validadores automáticos

Internet supuso una revolución sin precedentes en el mundo de la informática y de las comunicaciones. Es a la vez una oportunidad de difusión mundial, un mecanismo de propagación de la información y un medio de colaboración e interacción entre los individuos y sus computadoras independientemente de su localización geográfica (Leiner, 1999). Además, constituye un importante medio a través del cual las empresas y los organismos públicos suministran información a los usuarios. Teniendo en cuenta que la información se transfiere a través de mecanismos de comunicación, se presenta el siguiente escenario, relacionada con los municipios objetos de estudio, donde existe: i) Un emisor: el municipio; ii) Un receptor: el usuario; iii) El mensaje: información a transmitir; iv) Un código: idioma que utilizan el emisor y el receptor y v) Un canal: Internet. (Párrafo extraído del texto a modo de resumen)Facultad de Periodismo y Comunicación Socia

Estudio de accesibilidad web en el marco del proyecto "Tecnologías de la información y comunicación como herramientas del desarrollo local"

Se resume la línea de investigación vinculada con el estudio y análisis de accesibilidad y su medición en sitios web del NEA orientados a diversos dominios del conocimiento. El proyecto que se sintetiza, se enmarca en el Área de Ingeniería Web (AIW) de la Facultad de Ciencias Exactas y Naturales y Agrimensura de la Universidad Nacional del Nordeste En referencia a la formación de recursos humanos se concretó la defensa de tres tesinas de grado, una de ellas también desarrollada como beca de pregrado otorgada por la UNNE.Eje: Ingeniería de softwareRed de Universidades con Carreras en Informática (RedUNCI

The Information Coded in the Yeast Response Elements Accounts for Most of the Topological Properties of Its Transcriptional Regulation Network

The regulation of gene expression in a cell relies to a major extent on transcription factors, proteins which recognize and bind the DNA at specific binding sites (response elements) within promoter regions associated with each gene. We present an information theoretic approach to modeling transcriptional regulatory networks, in terms of a simple “sequence-matching” rule and the statistics of the occurrence of binding sequences of given specificity in random promoter regions. The crucial biological input is the distribution of the amount of information coded in these cognate response elements and the length distribution of the promoter regions. We provide an analysis of the transcriptional regulatory network of yeast Saccharomyces cerevisiae, which we extract from the available databases, with respect to the degree distributions, clustering coefficient, degree correlations, rich-club coefficient and the k-core structure. We find that these topological features are in remarkable agreement with those predicted by our model, on the basis of the amount of information coded in the interaction between the transcription factors and response elements

Implications of Differential Age Distribution of Disease-Associated Meningococcal Lineages for Vaccine Development

New vaccines targeting meningococci expressing serogroup B polysaccharide have been developed, with some being licensed in Europe. Coverage depends on the distribution of disease-associated genotypes, which may vary by age. It is well established that a small number of hyperinvasive lineages account for most disease, and these lineages are associated with particular antigens, including vaccine candidates. A collection of 4,048 representative meningococcal disease isolates from 18 European countries, collected over a 3-year period, were characterized by multilocus sequence typing (MLST). Age data were available for 3,147 isolates. The proportions of hyperinvasive lineages, identified as particular clonal complexes (ccs) by MLST, differed among age groups. Subjects <1 year of age experienced lower risk of sequence type 11 (ST-11) cc, ST-32 cc, and ST-269 cc disease and higher risk of disease due to unassigned STs, 1- to 4-year-olds experienced lower risk of ST-11 cc and ST-32 cc disease, 5- to 14-year-olds were less likely to experience ST-11 cc and ST-269 cc disease, and ≥25-year-olds were more likely to experience disease due to less common ccs and unassigned STs. Younger and older subjects were vulnerable to a more diverse set of genotypes, indicating the more clonal nature of genotypes affecting adolescents and young adults. Knowledge of temporal and spatial diversity and the dynamics of meningococcal populations is essential for disease control by vaccines, as coverage is lineage specific. The nonrandom age distribution of hyperinvasive lineages has consequences for the design and implementation of vaccines, as different variants, or perhaps targets, may be required for different age groups