On modified simple reacting spheres kinetic model for chemically reactive gases

Versão dos autores para esta publicação.

Aprendizaje durante la ontogenia temprana: Estudio de la participación del sistema opioide en la modulación de aprendizajes mediados por el etanol. LEARNING AND EARLY ONTOGENY: ANALYSIS OF THE INVOLVEMENT OF OPIOID SYSTEM IN FETAL AND INFANTILE ETHANOL-MEDIATED EXPERIENCIES.

Este plan de trabajos es continuidad de una línea de investigación centrada en evaluar los mecanismos responsables de la adquisición, expresión y persistencia de experiencias con el etanol. A partir de ello, indagar acerca de los efectos de esta experiencia sobre comportamientos de búsqueda y autoadministración de etanol en neonatos e infantes de rata. Se pretende analizar la participación del sistema opiáceo en los mecanismos implicados en una memoria fetal y/o infantil, generada como consecuencia de la exposición etílica. En una primera etapa, nos proponemos establecer de qué manera experiencias prenatales con la droga modulan el patrón de auto-administración de alcohol y otros reforzadores, como sacarosa. En este primer bloque de experimentos realizaremos manipulaciones fetales para determinar con mayor grado de especificidad la posible acción del sistema opiáceo en los mecanismos de adquisición de una memoria etílica prenatal. Se realizarán administraciones de etanol y el antagonista opiáceo, directamente a nivel fetal, y se evaluará esta experiencia en un paradigma de condicionamiento neonatal positivo, mediado por la droga. De acuerdo a la evidencia previa, esperamos que la exposición prenatal con la droga facilite la expresión de conductas de consumo y búsqueda del etanol o hacia las claves que señalizan al psicotrópico, tanto durante la infancia como en el neonato. A su vez, cuando la droga es presentada bajo los efectos de un antagonista opiáceo esperamos que estas conductas muestren un perfil similar a las desplegadas por sujetos controles. El segundo bloque de experimentos ha sido ideado con el objeto de indagar acerca de la posible participación del sistema opiáceo en la modulación de los aspectos reforzantes de la droga, a través de un esquema de auto-administración etílica infantil. Se utilizará un paradigma de condicionamiento instrumental adaptado para ratas infantes que consta de dos instancias, una de adquisición de la conducta instrumental (DPs 14-17) en la cual los animales reciben un pulso de refuerzo, como consecuencia de la ejecución de la conducta operante. En una segunda fase se analiza el patrón de búsqueda del reforzador ya que se registra la respuesta instrumental, sin que ocurra el refuerzo por la misma. Para analizar la participación del sistema opiáceo, durante la fase de adquisición de la conducta operante (DPs 16 y 17) los animales serán re-expuestos a mínimas cantidades del reforzador, bajo los efectos de un antagonista opiáceo, momentos previos al ensayo instrumental correspondiente para cada uno de estos días (Exp. 3). Esperamos que el bloqueo del sistema opiáceo, durante esta re-exposición al etanol, sea suficiente para disminuir el patrón de respuesta instrumental hacia el refuerzo etílico. Un último experimento incorporará un tercer evento de re-exposición al etanol -bajo los efectos del antagonista- previo al ensayo de extinción de la conducta instrumental (DP 18). Este nuevo evento tiene por objeto analizar la participación de este sistema neurobiológico en los mecanismos de búsqueda de etanol. Si el sistema opiáceo participa en la modulación de patrones tanto de búsqueda como consumatorios del reforzamiento por etanol, se espera que la re-exposición a la droga bajo los efectos del antagonista, inhiba estas respuestas tanto durante la sesión de adquisición, como de extinción de la conducta operante. Este proyecto intenta profundizar en el conocimiento de los mecanismos que regulan reconocimiento, aceptación, búsqueda y consumo de etanol, como consecuencia de experiencias tempranas con la droga. A su vez, es importante identificar y estudiar los sistemas neurobiológicos involucrados en estos mecanismos. Es por ello que se intenta determinar el rol que ejerce el sistema opiáceo en la adquisición de estas experiencias etílicas a nivel fetal e infantil, que se conoce promueven la búsqueda y el consumo de la droga. Our work is directed to analyze the involvement of the opioid system in the generation of pre- and early postnatal ethanol-related memories. As a first step, maternal manipulations with ethanol will be done. Infants will be evaluated in a paradigm of infantile self-administration of different reinforcers (ethanol, sucrose or water), employing a model of operant conditioning adapted to infant rats. A second experiment will be conducted in order to analyze if a central administration of ethanol, directly to the fetus, modifies subsequent patterns of neonatal conditioned responses to an artificial nipple, mediated by ethanol reinforcing effects. Fetal presentation of ethanol will be accompanied with the injection of an opioid antagonist in order to analyze the involvement of this system in acquisition processes of a fetal ethanol-mediated memory. A second set of studies will be conducted to analyze appetitive and consummatory behaviors in an infant model of ethanol self-administration. Involvement of opioid system in the acquisition or expression of this experience will be also inquired. Infant rats (PDs14-17) have to display a target behavior (nose-poke) to gain access to 5% sucrose or 3.75% ethanol. On PD18 an extinction session will be included. At PDs16-17, 6-hr before training, pups will be re-exposed to ethanol under opioid antagonism effects (naloxone). In a follow up experiment, a re-exposure trial will be included at PD18. Prior extinction, pups will receive naloxone and will be re-exposed to ethanol. We aim to observe if opioid system is modulating etha¬nol reinforcing effects, in terms of both appetitive and consummatory behaviors.

An investigation into system security requirements and implementation in an Application Service Provider (ASP) environment

Although the ASP model has been around for over a decade, it has not achieved the expected high level of market uptake. This research project examines the past and present state of ASP adoption and identifies security as a primary factor influencing the uptake of the model. The early chapters of this document examine the ASP model and ASP security in particular. Specifically, the literature and technology review chapter analyses ASP literature, security technologies and best practices with respect to system security in general. Based on this investigation, a prototype to illustrate the range and types of technologies that encompass a security framework was developed and is described in detail. The latter chapters of this document evaluate the practical implementation of system security in an ASP environment. Finally, this document outlines the research outputs, including the conclusions drawn and recommendations with respect to system security in an ASP environment. The primary research output is the recommendation that by following best practices with respect to security, an ASP application can provide the same level of security one would expect from any other n-tier client-server application. In addition, a security evaluation matrix, which could be used to evaluate not only the security of ASP applications but the security of any n-tier application, was developed by the author. This thesis shows that perceptions with regard to fears of inadequate security of ASP solutions and solution data are misguided. Finally, based on the research conducted, the author recommends that ASP solutions should be developed and deployed on tried, tested and trusted infrastructure. Existing Application Programming Interfaces (APIs) should be used where possible and security best practices should be adhered to where feasible.

A nutrient balance model for typical Irish farming systems

The twin objectives of the work described were to construct nutrient balance models (NBM) for a range of Irish animal production systems and to evaluate their potential as a means of estimating the nutrient composition of farm wastes. The NBM has three components. The first is the intake of nutrients in the animal's diet. The second is retention or the nutrients the animal retains for the production of milk, meat or eggs. The third is the balance or the difference between the nutrient intake and retention. Data on the intake levels and their nutrient value for dairy cows, beef cattle, pigs and poultry systems were assembled. Literature searches and interviews with National experts were the primary sources of information. NBMs were then constructed for each production system. Summary tables of the nutrient values for the common diet constituents used in Irish animal production systems, the nutrient composition of the animal products and the NBMs (nutrient intake, retention and excretion) for a range of production systems were assembled. These represent the first comprehensive data set of this type for Irish animal production systems. There was generally good agreement between the derived NBMs values and those published in the literature. The NBMs were validated on a number of farms. Data on animal numbers, fertiliser use, concentrates inputs and production output were recorded on seven farms. Using the data a nutrient input/output balance was constructed for each farm. This was compared with the NBM estimate of the farm nutrient balance. The results showed good agreement between the measured balance and the NBM estimate particularly for the pig and poultry farms. However, the validation emphasised the inherent risks associated with NBMs. The average values used for feed intake and production parameters in the NEMs may result in the under or over estimate of actual nutrient balances on individual farms where these variables are substantially different. On the grassland farms there was a poor correlation between the input/output estimate and the NBM. This possibly results from the omission of the soil's contribution to the nutrient balance. However, the results indicate that the NBMs developed are a potentially useful tool for estimating nutrient balances. They also will serve to highlight the significant fraction of the nutrient inputs into farming systems that are retained on the farm. The potential of the NBM as a means of estimating the nutrient composition of farm wastes was evaluated on two farms. Feed intake and composition, animal production, slurry production was monitored during the indoor winter feeding period. Slurry samples were taken for analysis. The appropriates NBMs were used to estimate the nutrient balance for each farm. The nutrient content of the slurry produced was calculated. There was a good agreement between the NBM estimate and the measured values. This preliminary evaluation suggests that the NBM has a potential to provide the farmer with a simple means of estimating the nutrient value of his slurry.

dynamics of the Becker-Döring model of nucleation

Magdeburg, Univ., Fak. für Mathematik, Diss., 2011

Qualitative and quantitative formal model-based safety analysis : push the safety button

Magdeburg, Univ., Fak. für Informatik, Diss., 2011

Data-driven system identification via evolutionary retrieval of Takagi-Sugeno fuzzy models

Systemidentification, evolutionary automatic, data-driven model, fuzzy Takagi-Sugeno grammar, genotype interpretability, toxicity-prediction

Active shape structural model

Shape model, deformable models, structural models, biometry, content based image retrieval, sketches

Experimental and model-based analysis of the steady-state and dynamic operating behaviour of the direct methanol fuel cell (DMFC)

Direct methanol fuel cell, DMFC, model, mass transport, Maxwell-Stefan, Flory-Huggins, crossover, polymer electrolyte membrane, Nafion

Cost-Effectiveness of High, Moderate and Low-Dose Statins in the Prevention of Vascular Events in the Brazilian Public Health System

Background:Statins have proven efficacy in the reduction of cardiovascular events, but the financial impact of its widespread use can be substantial.Objective:To conduct a cost-effectiveness analysis of three statin dosing schemes in the Brazilian Unified National Health System (SUS) perspective.Methods:We developed a Markov model to evaluate the incremental cost-effectiveness ratios (ICERs) of low, intermediate and high intensity dose regimens in secondary and four primary scenarios (5%, 10%, 15% and 20% ten-year risk) of prevention of cardiovascular events. Regimens with expected low-density lipoprotein cholesterol reduction below 30% (e.g. simvastatin 10mg) were considered as low dose; between 30-40%, (atorvastatin 10mg, simvastatin 40mg), intermediate dose; and above 40% (atorvastatin 20-80mg, rosuvastatin 20mg), high-dose statins. Effectiveness data were obtained from a systematic review with 136,000 patients. National data were used to estimate utilities and costs (expressed as International Dollars - Int$). A willingness-to-pay (WTP) threshold equal to the Brazilian gross domestic product per capita (circa Int$11,770) was applied.Results:Low dose was dominated by extension in the primary prevention scenarios. In the five scenarios, the ICER of intermediate dose was below Int$10,000 per QALY. The ICER of the high versus intermediate dose comparison was above Int$27,000 per QALY in all scenarios. In the cost-effectiveness acceptability curves, intermediate dose had a probability above 50% of being cost-effective with ICERs between Int$ 9,000-20,000 per QALY in all scenarios.Conclusions:Considering a reasonable WTP threshold, intermediate dose statin therapy is economically attractive, and should be a priority intervention in prevention of cardiovascular events in Brazil.

Influence of pore size distribution on drying behaviour of porous media by a continuous model

Bundle of capillaries, drying kinetics, continuous model, relative permeability, capillary pressure, control volume method

vertex effect in polycrystalline materials : simulation, a macroscopic model, and structural application

Polycrystal Plasticity, Yield-Vertex, Corner, Vertex-Effect, Microscale, Macroscale, Multiaxial, Torsional Buckling, Cruciform Column

SMPI model : a stepwise process model to facilitate software measurement process improvement along the measurement paradigms

Software engineering, software measurement, software process engineering, capability, maturity

Non-linear model reduction and control of molten carbonate fuel cell systems with internal reforming fuel cell systems with internal reforming

Magdeburg, Univ., Diss, 2007

Simulations for modelling of population balance equations of particulate processes using the discrete particle model (DPM)

Magdeburg, Univ., Fak. für Mathematik, Diss., 2009