Bounds for left and right window cutoffs

The location and width of the time window in which a sequence of processes converges to equilibrum are given under conditions of exponential convergence. The location depends on the side: the left-window and right window cutoffs may have different locations. Bounds on the distance to equilibrium are given for both sides. Examples prove that the bounds are tight

Limiting search cost distribution for the move-to-front rule with random request probabilities

Consider a list of $n$ files whose popularities are random. These files are updated according to the move-to-front rule and we consider the induced Markov chain at equilibrium. We give the exact limiting distribution of the search-cost per item as $n$ tends to infinity. Some examples are supplied.Comment: move-to-front, search cost, random discrete distribution, limiting distribution, size biased permutatio

The limiting move-to-front search-cost in law of large numbers asymptotic regimes

We explicitly compute the limiting transient distribution of the search-cost in the move-to-front Markov chain when the number of objects tends to infinity, for general families of deterministic or random request rates. Our techniques are based on a "law of large numbers for random partitions," a scaling limit that allows us to exactly compute limiting expectation of empirical functionals of the request probabilities of objects. In particular, we show that the limiting search-cost can be split at an explicit deterministic threshold into one random variable in equilibrium, and a second one related to the initial ordering of the list. Our results ensure the stability of the limiting search-cost under general perturbations of the request probabilities. We provide the description of the limiting transient behavior in several examples where only the stationary regime is known, and discuss the range of validity of our scaling limit.Comment: Published in at http://dx.doi.org/10.1214/09-AAP635 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org

Neutral space analysis for a Boolean network model of the fission yeast cell cycle network

BackgroundInteractions between genes and their products give rise to complex circuits known as gene regulatory networks (GRN) that enable cells to process information and respond to external stimuli. Several important processes for life, depend of an accurate and context-specific regulation of gene expression, such as the cell cycle, which can be analyzed through its GRN, where deregulation can lead to cancer in animals or a directed regulation could be applied for biotechnological processes using yeast. An approach to study the robustness of GRN is through the neutral space. In this paper, we explore the neutral space of a Schizosaccharomyces pombe (fission yeast) cell cycle network through an evolution strategy to generate a neutral graph, composed of Boolean regulatory networks that share the same state sequences of the fission yeast cell cycle.ResultsThrough simulations it was found that in the generated neutral graph, the functional networks that are not in the wildtype connected component have in general a Hamming distance more than 3 with the wildtype, and more than 10 between the other disconnected functional networks. Significant differences were found between the functional networks in the connected component of the wildtype network and the rest of the network, not only at a topological level, but also at the state space level, where significant differences in the distribution of the basin of attraction for the G1 fixed point was found for deterministic updating schemes.ConclusionsIn general, functional networks in the wildtype network connected component, can mutate up to no more than 3 times, then they reach a point of no return where the networks leave the connected component of the wildtype. The proposed method to construct a neutral graph is general and can be used to explore the neutral space of other biologically interesting networks, and also formulate new biological hypotheses studying the functional networks in the wildtype network connected component

Evaluación de factibilidad de un servicio integral de salud y bienestar para caninos considerando los aspectos estratégicos, técnicos, económicos y sociales

378 p.En el presente proyecto se lleva a cabo una evaluación de factibilidad de un servicio integral de salud y bienestar para caninos, el cual presenta sus bases en un emprendimiento de corte y baño de canes. De esta manera, en el presente estudio se busca solucionar una problemática identificada en la comuna de Santa Cruz, la cual muestra un aumento de la demanda por servicios asociados a la atención de mascotas desde el área de salud hasta la parte estética, y la oferta de la zona no ha seguido el mismo camino, es decir, se ha estancado, lo que actualmente se refleja en un colapso. La estructura de desarrollo se compone de tres grandes etapas, en primer lugar, se encuentra la realización de un diagnostico a través de un estudio de mercado del sector de las mascotas a nivel nacional y local, para posteriormente a través de una contribución metodológica donde el macro es el Design Thinking, se abordará de manera completa el problema latente, para plantear los posibles servicios que los solucionarían, los cuales, se ponen a prueba a través de una validación de clientes, con la contribución de metodología lean startup desarrollo de clientes, para finalmente obtener la propuesta de valor y los servicios a ofrecer. Posteriormente la segunda etapa parte con la elaboración de una propuesta de modelo y plan de negocios, la cual, se testeará con un rango más reducido de clientes a través de un Focus Group, lo que permitirá comprobar el entendimiento de la necesidad y tomar acciones correctivas para levantar el modelo de negocios final. A continuación, se aborda el plan de negocios que sustenta el proyecto, el cual, refleja los cuatro diversos lados de este, como lo son organizacional, mercado, operación, y financiero. Finalmente, la última etapa considera el analizar la factibilidad técnica, económica y social de la implementación de los servicios propuestos, reflejando la clara viabilidad de este proyecto

Chemical hypoxia induces pro-inflammatory signals in fat-laden hepatocytes and contributes to cellular crosstalk with Kupffer cells through extracellular vesicles

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated to intermittent hypoxia (IH) and is an aggravating factor of non-alcoholic fatty liver disease (NAFLD). We investigated the effects of hypoxia in both in vitro and in vivo models of NAFLD. METHODS: Primary rat hepatocytes treated with free fatty acids (FFA) were subjected to chemically induced hypoxia (CH) using the hypoxia-inducible factor-1 alpha (HIF-1α) stabilizer cobalt chloride (CoCl2). Triglyceride (TG) content, mitochondrial superoxide production, cell death rates, cytokine and inflammasome components gene expression and protein levels of cleaved caspase-1 were assessed. Also, Kupffer cells (KC) were treated with conditioned medium (CM) and extracellular vehicles (EVs) from hypoxic fat-laden hepatic cells. The choline deficient L-amino acid defined (CDAA)-feeding model used to assess the effects of IH on experimental NAFLD in vivo. RESULTS: Hypoxia induced HIF-1α in cells and animals. Hepatocytes exposed to FFA and CoCl2 exhibited increased TG content and higher cell death rates as well as increased mitochondrial superoxide production and mRNA levels of pro-inflammatory cytokines and of inflammasome-components interleukin-1β, NLRP3 and ASC. Protein levels of cleaved caspase-1 increased in CH-exposed hepatocytes. CM and EVs from hypoxic fat-laden hepatic cells evoked a pro-inflammatory phenotype in KC. Livers from CDAA-fed mice exposed to IH exhibited increased mRNA levels of pro-inflammatory and inflammasome genes and increased levels of cleaved caspase-1. CONCLUSION: Hypoxia promotes inflammatory signals including inflammasome/caspase-1 activation in fat-laden hepatocytes and contributes to cellular crosstalk with KC by release of EVs. These mechanisms may underlie the aggravating effect of OSAS on NAFLD. [Abstract word count: 257]

Discursos y prácticas racistas manifestadas por los profesores que dificultan la inclusión escolar de estudiantes migrantes de la Escuela Alemania de Paine.

263 h. (incluye anexos) : tablas.Determinar como la existencia de profesores de la Escuela Alemania de Paine que manifiestan prácticas y discursos racistas, dificultan la inclusión escolar de estudiantes migrantes, en una escuela que apuesta por la asimilación como forma de convivencia entre culturas, imposibilitando la inclusión de las comunidades migrantes en el contexto escolar.Trabajo de título (Asistente Social, grado de Licenciado en Trabajo Social

Construcción de maternidad en mujeres madres privadas de libertad en los recintos penitenciarios de Concepción, Chillán y Los Ángeles, Región del Bío-Bío

Ante el escenario actual de los recintos penitenciarios en el mundo, donde se presenta un inminente aumento de la población carcelaria femenina, es de interés estudiar la influencia de la privación de libertad en el mantenimiento del vínculo materno-filial, considerando que la mayoría de ellas son madres. En este estudio se entrevistó en profundidad a 50 mujeres madres pertenecientes a tres centros penitenciarios de la región del Biobío. Se observó, que pese a la privación de libertad, la mayoría de las madres perciben su relación materno-filial como cercana,  y  presentan expectativas positivas respecto a su futura relación con los/as hijos/as. En general, se identificó importantes consecuencias vivenciales derivadas del distanciamiento con su hijos/as y su privación de libertad.Las  construcciones que tanto las mujeres como sus hijos/as hacen a partir de la experiencia de privación de libertad  tienen relevantes implicaciones en las consecuencias de esta experiencia en el futuro