Electricity production from renewable energy resources such as wind energy and photovoltaics is variable. Integration of these intermittent resources into the electricity system leads to new challenges in how to manage imbalance between supply and demand on the grid. One way to meet these challenges is to develop so-called smart grid solutions. One idea, called demand response, is to adjust the amount or timing of energy consumption, e.g. by control of household appliances, to provide flexibility that could be used to balance the grid. In aggregate, when applied to many units across the system, large volumes of energy could be made available when needed and this grid flexibility can be used as a product on the electricity regulation market. Despite the potential benefits, the number of demand response bids is currently low. The aim of this thesis is to identify barriers in the Swedish regulation market, and togive Sweden's transmission system operator, Svenska kraftnät, recommendations on how to facilitate implementations of the technique. This has been done throughliterature studies and a wide range of interviews with people within the electricity market sector. The results indicate that a combination of several elements in the complex energy system impede the introduction of demand response. The main issues are related to market regulations and profitability difficulties. The authors recommend that Svenska kraftnät lowers the minimum bid size in all of the Swedish bidding areas, and adjusts the balance responsibility agreement and the system of balancing settlement.

The translational self-diffusion, the librations, and the reorientational motions of guest water molecules in the zeolite chabazite are examined by Molecular Dynamics (MD) computer simulations at different temperatures and loadings, including at room temperature, at which the experiments are carried out. Satisfactory agreement is found between the computed and measured translational self-diffusion coefficients. It is, however, furthermore found that the way in which the long-range electrostatic interactions are computed has an effect on the self-diffusion at high loadings and temperatures. The spectral densities of the librational motions of water are found to be similar to those in aqueous salt solutions. The reorientations of the water molecules, on the other hand, are much slower than in the liquids, and very anisotropic. The vector in direction of the molecular dipole moment reorients only very slowly, at the time scale of the simulations, due to the attraction to the almost immobile Ca++-ions and the walls of the zeolite. The other two vectors seem to undergo jump-reorientations rather than reorientations by a diffusion process. Hyper dynamics boost potential method has been applied to the MD simulations to estimate the self-diffusion coefficients of Ca++ ions in dehydrated chabazite. Because of our system is very complicated, the self-diffusion of Ca++ ions can only be roughly estimated. The Ca++ ions diffusion is small enough to confirm that the cation motion can be neglected in the normal MD simulation.

The zygote and blastomeres of cleavage stage mouse embryos have the capacity to differentiate to the embryonic and both extra-embryonic lineages and are considered functionally totipotent. Until now, it has not been possible to establish stable cell lines that resemble these totipotent-like cells. In this work, I hypothesised that by modulating signalling pathways known to be important in early embryonic development it may be possible to capture in vitro a self-renewing state that possessed features of pre-implantation blastomeres. I succeeded in formulating a novel hypothesis driven cell culture medium which allowed the establishment of a stem cell state that possessed expanded differentiation potential to the embryonic and both extra-embryonic lineages in vitro and in vivo. These cells were isolated directly from in vitro culture of mouse pre-implantation embryos or single cell blastomeres, reprogrammed from somatic cells or converted from mouse ES cells. With these cells, I generated single cell chimeras which demonstrated extensive contribution to all lineages in the developing organism providing additional evidence that this chemical medium maintained a homogenous stem cell population. I demonstrated that the transcriptome of these cells was enriched with an early pre-implantation blastomere signature, distinct from other rare published totipotent-like cells. Finally, I demonstrated that the same chemical formulation permitted the establishment in vitro of a human stem cell state that possessed expanded differentiation potential to the embryonic and extra-embryonic lineage in vitro. My work has shown for the first time that through chemical modulation of pathways implicated to be involved in pre-implantation development, a novel homogenous stem cell state that possesses a pre-implantation transcriptional signature and expanded differentiation potential to both the embryonic and extra-embryonic lineage can be established and maintained in vitro in both mouse and human, suggesting a possible interspecies conservation of the signalling networks involved in early embryonic development.

Orientador: Stefano de Leo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Científica / Made available in DSpace on 2018-08-15T11:34:18Z (GMT). No. of bitstreams: 1 Silva_KeniaCristinaPereira_M.pdf: 5917573 bytes, checksum: 689b0e6d7c10b6ea1e4524486138cc7e (MD5) Previous issue date: 2010 / Resumo: O objetivo principal deste trabalho é estudar a equação de Schrödinger para um potencial quaterniônico tipo barreira. A solução analítica encontrada permite comparar qualitativamente as diferenças entre a mecânica quântica complexa e a mecânica quântica quaterniônica. Antes de apresentar a solução analítica da barreira, para um melhor entendimento da motivação que leva ao estudo de uma mecânica quântica quaterniônica, será analisado em detalhes (ondas planas e pacotes de onda) o potencial tipo degrau / Abstract: The main objective of this research is to study the Schrödinger equation for a quaternionic potential barrier. The analytical solution found allow us to compare qualitatively the differences between the complex quantum mechanics and the quaternionic quantum mechanics. Before presenting the barrier analytical solution, to a better understanding of the motivation that leads us to the study of quaternionic quantum mechanics, the potencial step will be discussed in detail (plane waves and wave packets) / Mestrado / Fisica-Matematica / Mestre em Matemática Aplicada

Potential Fields is an obstacle avoidance and general path-finding technique that has only quite recently started to be used in AI for video games. It has previously mainly been used in robotics for robot navigation. Although quite unexplored, Potential Fields have so far worked well in video games. Previous research has mainly focused on RTS (Real-Time Strategy) games. This research explores the use of Potential Fields in another genre called arena games (which is a quite unexplored genre as well). In the implementation, multiple Potential Fields have been used together, where each field had a different task. Also, weights were used on the different Potential Fields to give them different importance depending on some factors that are dynamic through the game, hence the use of the word weighted. The main focus of the user studies conducted was the impact the weights had on the computer controlled unit's general behaviour. The user studies conducted showed that it was hard to determine who was a computer controlled character and who was human controlled, therefore telling that multiple Potential Fields worked well for movement. The test participants became better at determining this the second match they played, no matter the properties of the match. However, the user studies did not show that the weights made a remarkable difference; there was no significant improvement on the situation adaptation and team cooperation, but no deterioration either. The concept of using weights needs to be explored further.

Abstract Natural seasonal variation and the effects of cold treatment and nitrogen fertilization on protein expression with special emphasis on dehydrin proteins, were studied using different aged Scots pine (Pinus sylvestris L.). Several different dehydrins were found and their expression depended on the tissue type, tree age or specific treatment. Their concentrations fluctuated seasonally and in response to nitrogen fertilization, but no effects of low temperature on the dehydrins of seedlings were observed. A 60-kDa dehydrin was associated with cold acclimation in the bud and bark tissues of mature trees and in the needles of seedlings. In the needles of mature trees, this dehydrin was associated with springtime desiccation, which was detected as a significant decrease in the osmotic potential of needles. The quantity and quality of soluble proteins altered seasonally in Scots pine tissues, but low temperature treatment alone did not have any effect on the proteins. Soluble protein concentration increased during autumn and decreased in spring in buds and bark, but not in the needles of mature trees. In needles of seedlings, however, protein concentrations altered seasonally. Several proteins, of varying molecular weights, were more abundant in winter in all the tissues studied and some increased in concentration in the nitrogen-fertilized seedlings. The role of these proteins as a storage reserve in Scots pine is discussed. The osmotic potential of needles showed seasonal fluctuation, being high in the summer and low during the winter. Low temperature treatment decreased the osmotic and water potential of needles and increased the concentrations of soluble sugars in seedlings. Based on carbohydrate analyses, the metabolism of seedlings acclimated to low temperature in less than ten days. Nitrogen fertilization increased the content of total nitrogen and the soluble protein concentrations in the needles of seedlings and the growth both in the mature trees and seedlings. Although the frost resistance showed no response to nitrogen-fertilization, the soluble proteins and dehydrins were affected in a manner that suggested an earlier growth resumption of spring in the fertilized trees.

The purpose of this thesis is to investigate whether Okun’s law is valid within Sweden. Furthermore, we are also interested in studying how it varies with different genders and age groups. Quarterly data on GDP and unemployment between the years 1980 to 2015 is used. Three different models have been tested on their ability to estimate Okun’s law and the model with the highest explanatory power was chosen. The results show that unemployment among men are more affected by changes in GDP growth than women, which likely is because more men tend to work in the private sector and women in the public sector. Young workers are also affected to a greater degree than older workers, due to how the employment protection act (LAS) works in Sweden. / Syftet med uppsatsen är främst att undersöka den så kallade Okuns lag i Sverige, och mer specifikt studera om sambandet varierar mellan kön och åldersgrupper. Kvartalsdata på BNP och arbetslöshet mellan åren 1980 till 2015 har använts. Tre olika modeller har testats på hur väl de kunde förklara Okuns lag i Sverige, varav den ena modellen hade högre förklaringsgrad. Resultaten visar att män påverkades till en högre grad av förändringar i ekonomins tillväxt än kvinnor. Detta beror sannolikt på att män i högre grad tenderar att jobba inom den privata sektorn och kvinnor inom offentliga sektorn, vilken inte är lika känslig för konjunktursvängningar. Vi fann även att yngre arbetare påverkas till en högre grad än äldre av förändringar i ekonomins tillväxt. Detta beror sannolikt på hur lagen om anställningsskydd (LAS) är uppbyggd i Sverige.

Le potentiel d'action est un des événements de signalisation majeurs du cerveau. Ce travail est dédié à l'étude de la génération du potentiel d'action, et son impact dans le potentiel extracellulaire ainsi que dans le réseau local. Pour ce faire nous avons abordé trois questions principales. Premièrement, nous nous sommes intéressés à comprendre pourquoi les potentiels d'action ont souvent un début brutal dans les enregistrements somatiques des neurones de mammifères. Nous avons montré que l'hypothèse du couplage résistive critique explique comment le potentiel d'action est initié dans le segment initial de l'axone pour fournir le 'kink' dans le soma. Deuxièmement, nous avons évalué l'impact de la position du segment initial sur le potentiel extracellulaire. De façon importante, nous démontrons que l’impact de la position du segment initial axonal dans la forme et l’amplitude du potentiel d’action dépend de la distance entre le site d’enregistrement et l’axone, et de sa position par rapport à l’axe soma-segment initial axonal.Finalement, nous avons exploré l’impact d’un seul potentiel d’action dans l’activité de réseau, car cet effet est souvent questionné. Nos montrons qu’un seul potentiel d’action d’un neurone pyramidal hippocampique peut commencer l’activité «sharp-wave ripple” qui consiste en l’activation de multiple interneurones. L’ensemble de nos résultats montre que les potentiels d’action sont des événements complexes modelés par la biochimie de le membrane neuronale et la morphologie de l’axone. De plus, ces caractéristiques neuronales modulent fortement leur impact dans le champ extracellulaire et l’activité de réseau. / The action potential is considered one of the major signaling events in the brain.Although it has been studied for years, many questions remain unanswered. The present work is dedicated to the study of action potential generation, its impact on extracellular field and local network establishment. We considered three questions: Firstly, (i) we asked why mammalian neurons often have characteristically sharp onset in the somatic recordings of action potentials. We show that the Critical Resistive Coupling Hypothesis is sufficient to explain how the action potential is initiated in the axon initial segment to provide for the ‘kink’ in the soma, while the Back propagation Hypothesis is not sufficient to explain it. Next, (ii)we asked how the placement of the axon initial segment might affect the extracellular field. We show that the impact of the axon initial segment position on the shape and amplitude ofextracellular action potential depends on the distance between the recording site andthe axon and on its position along the soma–axon initial segment axis. Finally, (iii)we inquired if a single action potential might have an effect on the network activity. Weshow that a single action potential from a single pyramidal neuron in the hippocampus can trigger sharp-wave ripple activity consisting of the firing of multiple interneurons.Altogether, our results show that action potentials are complex events shaped by the biochemistry of the neuronal membrane and morphology of the axon. In addition these features strongly modulate the neuron’s impact on the extracellular field and network activity.

L’hypertension pulmonaire (HTP) est la principale pathologie de la circulation pulmonaire et a un très mauvais pronostic. Elle se caractérise par une hyperréactivité et un remodelage des petites artères pulmonaires (AP) entraînant une augmentation progressive des résistances vasculaires pulmonaires, qui, ultimement, aboutit à une insuffisance cardiaque droite et au décès du patient. Il est admit que le calcium joue un rôle très important aussi bien dans les mécanismes de remodelage que dans l’hyperréactivité des AP observés dans l’HTP. Dans le présent travail, nous avons étudié l’expression et le rôle d’une famille particulière de canaux calciques, les TRPV, dans les AP de rats contrôles (normoxiques) et souffrant d’hypertension pulmonaire (rats hypoxiques chroniques et traités à la monocrotaline). Nous montrons que (1) les canaux TRPV1, V2 et V4 sont exprimés dans les AP et que cette expression est augmentée au cours de l’HTP ; (2) la stimulation de ces canaux par des agonistes spécifiques induit une augmentation de la concentration calcique intracellulaire dans les cellules musculaires lisses (CML) ; (3) le récepteur à la ryanodine de type 2 (RRy 2) du réticulum sarcoplasmique est impliqué dans la voie de signalisation dépendante de TRPV4 et que son expression est également augmentée au cours de l’HTP ; (4) les canaux TRPV1 et TRPV4 sont impliqués dans la migration des CML, processus fondamental du remodelage ; (5) les contractions induites par l’activation de TRPV2 et TRPV4 dans les AP de rats hypertendus sont significativement diminuées par la streptomycine, un inhibiteur des canaux SAC (stretch activated channels). Ce travail démontre donc l’implication des canaux TRPV à la fois dans l’hyperréactivté et le remodelage des AP. De nouveaux traitements ciblant les canaux TRPV pourraient constituer une approche thérapeutique innovante de l’hypertension pulmonaire. / Pulmonary hypertension (PH)) is the primary pathology of the pulmonary circulation and has a very bad prognostic. This disease is characterized by a hyperreactivity and remodelling of small pulmonary arteries (PA) leading to a progressive increase in pulmonary vascular resistance which ultimately leads to right heart failure and death of the patient. It is admitted that calcium plays an important role both in the mechanisms of remodelling and in the hyperresponsiveness of PA observed in PH. In the present work, we studied the expression and the role of a particular family of calcium channels, TRPV channels, in PA from control rats (normoxic) and pulmonary hypertensive rats (chronically hypoxic and monocrotaline-treated rats). We show that (1) TRPV1, V2 and V4 channels are expressed in the PA and that their expression are increased in PH; (2) stimulation of these channels by specific agonists induces an increase in the intracellular calcium concentration in smooth muscle cells (SMC), (3) the ryanodine receptor type 2 (RRy2) of the sarcoplasmic reticulum is involved in the TRPV4-dependent signaling pathway and its expression is also increased in PH, (4) TRPV1 and TRPV4 channels are involved in the migration of SMC, the fundamental process of remodelling, (5) contractions induced by activation of TRPV2 and TRPV4 in the PA from hypertensive rats are significantly decreased by streptomycine, an inhibitor of stretch activated channels (SAC). This work thus demonstrates the involvement of TRPV channels in both the hyperreactivity and remodelling of PA. New treatments targeting TRPV channels could be an innovative therapeutic approach for pulmonary hypertension.

Trade and Investment relations between the Czech Republic and Ecuador aims to a better understanding of their international connection level. First, the research pretends to inform any business person about the business and trade panorama of the Czech Republic. Secondly, it describes the business and trade panorama of Ecuador. Thirdly and after analyzing each nation, it reports their bilateral trade relations in a quantitative way. Finally, it contributes with conclusions of the research including potential products for trade. The thesis is intended to overcome geographic and cultural constrains between the two nations in order to make a trade analysis looking for integrations between these markets.