121.
Estudio del proceso de salida del parásito Leishmania amazonensis de su célula hospedera / Study of host cell egress by the parasite Leishmania amazonensis - Quintana Varón, María del Pilar
Los parásitos del género Leishmania, son protozoarios intracelulares obligados que en su ciclo de vida incluyen un estadío en un hospedero vertebrado, dentro del cual se establece principalmente en macrófagos. Allí, la infección es sostenida por amastigotes, para lo cual es necesario que se dé un evento de liberación de éstos; dicho modelo de liberación no ha sido establecido, y se han planteado dos mecanismos básicos: (1) la salida por ruptura de la membrana de la vacuola parasitófora (MVP) y la membrana plasmática del macrófago (MPM) o (2) la salida se da por un proceso de fusión entre la MVP...
122.
Analysis of the eolic harnessing of mountain and valley winds in several places of Pyrenees. - Viñallonga Pijoan, Jordi
Sota el context actual de canvi climàtic que està patint el nostre país, en aquest escrit es proposa una possible nova font d‟energia alternativa a les muntanyes: l‟aprofitament dels corrents tèrmics.Els cims de les muntanyes a les nits es refreden més ràpidament que no pas el fons de la vall provocant que l‟aire fred, dens i pesat llisqui pels pendents avall. Aquest fenomen s‟anomena vent catabàtic. Per cas contrari, durant el dia l‟aire a la vall s‟escalfa més que als cims. L‟aire calent és menys dens i lleuger i per tant puja pels pendents cap als cims. Aquest fenomen s‟anomena...
124.
Conceitos de regulação em saúde no Brasil - Oliveira,Robson Rocha de; Elias,Paulo Eduardo Mangeon
São revisados os conceitos de regulação em saúde empregados em publicações científicas nacionais sobre gestão em saúde. Elaborou-se uma tipologia para os conceitos de regulação a partir das ideias mais correntes em cinco disciplinas: ciências da vida, direito, economia, sociologia e ciência política. Quatro ideias destacaram-se: controle, equilíbrio, adaptação e direção, com maior ênfase para a natureza técnica da regulação. A natureza política da regulação ficou em segundo plano. Considera-se que a discussão do conceito de regulação em saúde relacionou-se com a compreensão do papel que o Estado exerce nesse setor. A definição das formas de intervenção do Estado é...
125.
Aislamiento y selección de lactobacillus sp con potencial probiótico a partir de pan de abejas - Moreno Galarza, Lizeth Johanna
En el presente estudio se aisló, caracterizó y evaluó cepas de Lactobacillus sp con potencial probiótico a partir de pan de abejas de Apis mellifera; las cepas fueron incorporadas como bacterias probioticas mediante fermentación in vitro en polen apícola para así lograr un potencial producto funcional. Se procesaron 38 muestras de pan de abejas en el medio de cultivo, Man Rogosa Sharpe (MRS), se realizó pruebas bioquímicas para su identificación. Entre las pruebas para evaluar la capacidad probiótica se determinó: tolerancia a pH ácido (3, 4 y 5), crecimiento en bilis (0.3, 0.5 y 1.0%), actividad hemolítica, actividad antibacteriana frente...
132.
Optimization methods for individual-based model parameter estimation in predictive microbiology - Prats Soler, Clara; Bernaerts, K.; Standaert, A.; Ferrer Savall, Jordi; López i Codina, Daniel; Van Impe, J.
In the framework of microbiology, Individual-based Models are discrete models inwhich the main entities are microbes. Their use in simulations as ‘virtual experiments’ to predictthe evolution of populations under specific conditions requires accurate setting of the parametersinvolved. We adapted and tested two optimization methods for Individual-based Model parameterestimation: the Nelder-Mead Threshold Accepting (NMTA) and the NEWUOA. These methodspresented no convergence problems, and the best results in terms of time expenditure were derivedwith the latter.
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Effect of environmental fluctuations on invasion fronts - Mendez, Vicenç; Llopis Fuste, Isaac; Campos, Daniel; Horsthemke, Werner
We determine the density profile and velocity of invasion fronts in one-dimensional infinite habitats in the presence of environmental fluctuations. The population dynamics is reformulated in terms of a stochastic reaction–diffusion equation and is reduced to a deterministic equation that incorporates the systematic contributions of the noise. We obtain analytical expressions for the front profile and velocity by constructing a variational principle. The effect of the noise differs, depending on whether it affects the density-independent growth rate, the intraspecific competition term or the Allee threshold. Fluctuations in the density-independent growth rate increase the invasion velocity and the population density of...
135.
Exploring the lag phase and growth initiation of a yeast culture by means of an individual-based model - Ginovart Gisbert, Marta; Prats Soler, Clara; Portell Canal, Xavier; Silbert, Moises
The performance of fermentation processes is greatly influenced by the size and quality of inocula. The characterization of the replicative age is decided by the number of birth scars each yeast exhibits on its cellular membrane. Yeast ageing and inoculum size are factors that affect industrial fermentation, particularly those processes in which the yeast cells are reused such as the production of beer. This process reuses yeast cropped at the end of one fermentation in the following one, in a process called “serial repitching”. The aim of this study was to explore the effects of inoculum size and ageing on...
136.
INDISIM, an individual based discrete simulation model to study bacterial cultures - Ginovart Gisbert, Marta; López i Codina, Daniel; Valls Ribas, Joaquim
An individual-based model has been developed and designed to simulate the growth and behaviour of bacterial colonies. The simulator is called INDISIM, which stands forINDividual DIScrete SIMulations. INDISIM is discrete in space and time, and controlsa group of bacterial cells at each time step, using a set of random, time-dependent variables for each bacterium. These variables are used to characterize its position in space, biomass, state in the cellular reproduction cycle as well as other individual properties. The space where thebacterial colony evolves is also discrete. A physical lattice is introduced, subject to the appropriate boundary conditions. The lattice is...
139.
Individual-based Modelling of microbial activity to study mineralization of C and N and nitrification process in soil - Ginovart Gisbert, Marta; López i Codina, Daniel; Gras, Anna
This work models the dynamics and evolution of carbon (C) and nitrogen (N) related to organic matter in soils by using individual-based simulations. The simulator INDISIM-SOM controls a group of microbial cells at each time step, using a set of time-dependent variables for each microorganism. The space is divided into square cells. In each spatial cell, the amounts of different types of organic compounds are controlled. These are identified as polymerized organic C and N, labile organic C and N, mineral compounds likeNNH4,NNO3,CO2 andO2. The model takes into account the activity of two prototypes of microbial cells: ammonifier microorganisms and...
140.
Simulació discreta de sistemes biològics: una potent eina en la recerca en ciència i tecnologia - López i Codina, Daniel; Ginovart Gisbert, Marta; Valls Ribas, Joaquim; Sole, Ricard Vicenç
La simulació discreta és una eina Útilper estudiar i entendre sistemes cornplexos.S'ha elaborat un programa de simulaciódiscreta per l'estudi de sisternes ecologics.S'ha desenvolupat amb profunditat una versió del programa per l'estudi de cultius bacterians. S'explica, esquematicarnent,quines són les diferents parts del programa i el seu funcionament.Es fa un resum de quins han estat els resultats més importants assolits amb la utilització del simulador en l'estudi i investigació de cultiusbacterians.També es presenten alguns resultats d'interes en ecologia. Es comentenles possibilitats actuals de la simulació,en les quals ja s'ha començat a treballar.Es discuteixen finalment algunes de lesnoves perspectives d'utilització del simulador.
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