299 research outputs found
Non-centralized Control for Flow-based Distribution Networks: A Game-theoretical Insight
This paper solves a data-driven control problem for a flow-based distribution network with two objectives: a resource allocation and a fair distribution of costs. These objectives represent both cooperation and competition directions. It is proposed a solution that combines either a centralized or distributed cooperative game approach using the Shapley value to determine
a proper partitioning of the system and a fair communication cost distribution. On the other hand, a decentralized noncooperative game approach computing the Nash equilibrium is used to achieve the control objective of the resource allocation under a non-complete information topology. Furthermore, an invariant-set property is presented and the closed-loop system stability is analyzed for the non cooperative game approach. Another contribution regarding the cooperative game approach is an alternative way to compute the Shapley value for the proposed specific characteristic function. Unlike the classical
cooperative-games approach, which has a limited application due to the combinatorial explosion issues, the alternative method allows calculating the Shapley value in polynomial time and hence can be applied to large-scale problems.Generalitat de Catalunya FI 2014Ministerio de Ciencia y Educación DPI2016-76493-C3-3-RMinisterio de Ciencia y Educación DPI2008-05818Proyecto europeo FP7-ICT DYMASO
Energy Efficiency of Hybrid-Power HetNets: A Population-like Games Approach
In this paper, a distributed control scheme based on population games is proposed. The controller is in charge of dealing with the energy consumption problem in a Heterogeneous Cellular Network (HetNet) powered by hybrid energy sources (grid and renewable energy) while guaranteeing appropriate quality of service (QoS) level at the same time. Unlike the conventional approach in population games, it considers both atomicity and non-anonymity. Simulation results show that the proposed population-games approach reduces grid consumption by up to about 12% compared to the traditional best-signal level association policy.U.S. Air Force Office of Scientific Research FA9550-17-1-0259Ministerio de Cultura y Deporte DPI2016-76493-C3-3-RMinisterio de Economía y Empresa DPI2017-86918-
Otimização de um método baseado em matrizes de multi-elétrodos (MEA) para o estudo do impacto do Aβ na linha celular SH-SY5Y
Mestrado em Biomedicina MolecularThe human brain stores, integrates, and transmits information recurring to millions of neurons, interconnected by countless synapses. Though neurons communicate through chemical signaling, information is coded and conducted in the form of electrical signals. Neuroelectrophysiology focus on the study of this type of signaling. Both intra and extracellular approaches are used in research, but none holds as much potential in high-throughput screening and drug discovery, as extracellular recordings using multielectrode arrays (MEAs). MEAs measure neuronal activity, both in vitro and in vivo. Their key advantage is the capability to record electrical activity at multiple sites simultaneously.
Alzheimer’s disease (AD) is the most common neurodegenerative disease and one of the leading causes of death worldwide. It is characterized by neurofibrillar tangles and aggregates of amyloid-β (Aβ) peptides, which lead to the loss of synapses and ultimately neuronal death. Currently, there is no cure and the drugs available can only delay its progression. In vitro MEA assays enable rapid screening of neuroprotective and neuroharming compounds. Therefore, MEA recordings are of great use in both AD basic and clinical research.
The main aim of this thesis was to optimize the formation of SH-SY5Y neuronal networks on MEAs. These can be extremely useful for facilities that do not have access to primary neuronal cultures, but can also save resources and facilitate obtaining faster high-throughput results to those that do.
Adhesion-mediating compounds proved to impact cell morphology, viability and exhibition of spontaneous electrical activity. Moreover, SH-SY5Y cells were successfully differentiated and demonstrated acute effects on neuronal function after Aβ addition. This effect on electrical signaling was dependent on Aβ oligomers concentration.
The results here presented allow us to conclude that the SH-SY5Y cell line can be successfully differentiated in properly coated MEAs and be used for assessing acute Aβ effects on neuronal signaling.O cérebro humano armazena, integra e transmite informação recorrendo a milhões de neurónios, interconetados por inúmeras sinapses. Embora os neurónios comuniquem entre si através de sinais químicos, a informação é codificada e conduzida sob a forma de sinais elétricos. A neuroeletrofisiologia foca-se no estudo deste tipo de sinalização. Tanto abordagens intra, como abordagens extracelulares são usadas em investigação, mas nenhuma detém tanto potencial em screening de alto débito e na descoberta de fármacos, como medições extracelulares baseadas em matrizes de multi-elétrodos (MEA). MEAs medem a atividade neuronal, tanto em in vitro como em in vivo. A sua principal vantagem é a capacidade de medir atividade elétrica a partir de vários locais simultaneamente.
A doença de Alzheimer (DA) é a doença neurodegenerativa mais comum e uma das principais causas de morte em todo o mundo. É caracterizada por emaranhados neurofibrilares e agregados de péptidos amilóides (Aβ), que conduzem à perda de sinapses e em última instância, à morte neuronal. Atualmente, não existe cura e os tratamentos disponíveis apenas retardam a sua progressão. Os ensaios in vitro com MEA permitem uma seleção rápida dos compostos neuroprotectores e neurotóxicos. Portanto, as medições com recurso a MEA são de grande utilidade na investigação básica e clínica da DA.
O principal objetivo desta tese foi otimizar a formação de redes neuronais SH-SY5Y em MEAs. Estas podem ser extremamente úteis para instalações que não têm acesso a culturas neuronais primárias, mas também podem economizar recursos e facilitar a obtenção mais rápida de resultados para aquelas que têm acesso.
Compostos mediadores de adesão provaram afetar a morfologia, viabilidade e a exibição espontânea de atividade elétrica das células. Além disso, as células SH-SY5Y foram diferenciadas com sucesso e demonstraram efeitos agudos sobre a função neuronal após a adição de Aβ. Este efeito sobre a sinalização elétrica foi dependente da concentração dos oligómeros de Aβ.
Os resultados aqui apresentados permitem concluir que a linha celular SH-SY5Y pode ser diferenciada com sucesso em MEAs devidamente tratados e pode ser usada para avaliar os efeitos agudos do Aβ sobre a sinalização neuronal
Armaduras cuadradas y ochavadas en Galicia. Análisis histórico-constructivo
lncluído en el libro: Actas del Úndécimo Congreso Nacional de Historia de la Construcción, que recoge las Actas presentadas en el Congreso Nacional de Historia de la Construcción celebrado en Soria del 9 al 12 de octubre de 2019
Phylogeography of a widespread species: pre-glacial vicariance, refugia, occasional blocking straits and long-distance migrations
Phylogeographic studies give us the opportunity to reconstruct the historical migrations of species and link them with climatic and geographic variation. They are, therefore, a key tool to understanding the relationships among biology, geology and history. One of the most interesting biogeographical areas of the world is the Mediterranean region. However, in this area, the description of concordant phylogeographic patterns is quite scarce, which limits the understanding of evolutionary patterns related to climate. Species with one-dimensional distribution ranges, such as the strawberry tree ( Arbutus unedo ), are particularly useful to unravel these patterns. Here, we describe its phylogeographic structure and check for concordance with patterns seen in other Mediterranean plants: longitudinal/latitudinal clines of diversity, evidence for glacial refugia and the role of sea straits in dispersal. We also identify the most likely source for the disjunct Irish population. With this aim, we sequenced four chloroplast non-coding fragments of A. unedo from 23 populations covering its whole distribution. We determined the genetic diversity, population structure, haplotype genealogy and time to the most recent common ancestor. The genealogy revealed two clades that separated during the last 700 ky but before the last glacial maximum. One clade occupies Atlantic Iberia and North Africa, while the other occurs in the Western Mediterranean. The Eastern Mediterranean is inhabited by newer haplotypes derived from both clades, while the Irish population is closely related to Iberian demes. The straits of Sicily and Gibraltar partially restricted the gene flow. We concluded that a vicariance event during the Late Quaternary in the western end of the species' range followed by eastward migration seems a likely explanation for the observed phylogeographic pattern. The role of straits indicates an occasional communication between Europe and North Africa, suggesting that the latter was a novel refugia. The East–West genetic split in Iberia is consistent with the refugia-within-refugia model. Finally, the strawberry tree possibly reached Ireland from Iberia instead of throughout the maritime fringe of France as previously thoughtThis work was supported by the Spanish Ministry of Science and Innovation (research grant CGL2009-11356), the European Regional Development's Fund (ERDF) and also by the Spanish Ministry of Education (FPU fellowship AP-2009-0962 to X.S.)S
Population Structure of a Widespread Species under Balancing Selection: The Case of Arbutus unedo L.
Arbutus unedo L. is an evergreen shrub with a circum-Mediterranean distribution that also reaches the Eurosiberian region in northern Iberia, Atlantic France, and a disjunct population in southern Ireland. Due to the variety of climatic conditions across its distribution range, the populations of A. unedo were expected to display local adaptation. Conversely, common garden experiments revealed that diverse genotypes from a range of provenances produce similar phenotypes through adaptive plasticity, suggesting the action of stabilizing selection across its climatically heterogeneous range. Nonetheless, since a uniform response might also result from extensive gene flow, we have inferred the population structure of A. unedo and assessed whether its extended and largely one-dimensional range influences gene flow with the help of AFLP genotypes for 491 individuals from 19 populations covering the whole range of the species. As we had anticipated, gene flow is restricted in A. unedo, providing further support to the hypothesis that stabilizing selection is the most likely explanation for the homogeneous phenotypes along the range. The Euro-Siberian populations were not particularly isolated from the Mediterranean. Instead, there was a distinct genetic divide between the populations around the Mediterranean Sea and those sampled along Atlantic coasts from northern Africa up to Ireland. This genetic structure suggests the action of historic rather than biogeographic factors as it seems consistent with a scenario of independent glacial refugia in the Atlantic and Mediterranean portions of the range of A. unedo. Genetic exchange was likewise restricted within each set of populations. Nevertheless, isolation-by-distance (IBD) was stronger, and FST increased faster with distance, along the Atlantic, suggesting that gene flow might be larger among Mediterranean populations. Genetic diversity was significantly lower in NW Iberia and Ireland than in other populations whereas Ireland was more closely related to populations in NW Iberia than to a population in Atlantic France, suggesting a postglacial stepping-stone colonization of the Atlantic coast. Altogether, our results show that stabilizing selection is able to homogenize the phenotypic response even when population structure is strong, gene flow is constrained, and the phylogeographic past is complexThis research was supported by research grant CGL2009-11356 (Ministerio de Ciencia e Innovación) and FPU fellowship AP-2009-0962 (Ministerio de Educación). This research was also supported by the European Regional Development's Fund (ERDF)S
Efectos de los costes de cambio y de retención sobre el bienestar social en el servicio postal europeo
[Resumen] Una política que fortalece la competencia a largo plazo en el sector postal es la actuación sobre los costes
de cambio y de retención. En dos escenarios de duopolio, uno con costes de cambio y otro con costes de cambio y costes de retención, el objetivo del presente trabajo es descubrir en qué medida la variación de los costes de cambio de proveedor y de los costes de retención afectan al excedente del consumidor y al beneficio de las dos
firmas y, en consecuencia, al bienestar social. Se desarrolla una ampliación propia del modelo seminal de Klemperer,
que incorpora los costes de retención. La metodología consiste en la determinación y comparación de las situaciones del equilibrio Cournot- Nash. Los resultados obtenidos muestran la importancia de las políticas orientadas a la reducción de los costes de cambio de proveedor como una de las políticas que fortalecen la competencia a largo plazo en un servicio de interés general, como es el servicio postal
Cytoplasmic- and extracellular-proteome analysis of Diplodia seriata: a phytopathogenic fungus involved in grapevine decline
<p>Abstract</p> <p>Background</p> <p>The phytopathogenic fungus <it>Diplodia seriata</it>, whose genome remains unsequenced, produces severe infections in fruit trees (fruit blight) and grapevines. In this crop is recognized as one of the most prominent pathogens involved in grapevine trunk disease (or grapevine decline). This pathology can result in the death of adult plants and therefore it produces severe economical losses all around the world. To date no genes or proteins have been characterized in <it>D. seriata </it>that are involved in the pathogenicity process. In an effort to help identify potential gene products associated with pathogenicity and to gain a better understanding of the biology of <it>D. seriata</it>, we initiated a proteome-level study of the fungal mycelia and secretome.</p> <p>Results</p> <p>Intracellular and secreted proteins from <it>D. seriata </it>collected from liquid cultures were separated using two-dimensional gel electrophoresis. About 550 cytoplasmic proteins were reproducibly present in 3 independent extractions, being 53 identified by peptide mass fingerprinting and tandem mass spectrometry. The secretome analysis showed 75 secreted proteins reproducibly present in 3 biological replicates, being 16 identified. Several of the proteins had been previously identified as virulence factors in other fungal strains, although their contribution to pathogenicity in <it>D. seriata </it>remained to be analyzed. When <it>D. seriata </it>was grown in a medium supplemented with carboxymethylcellulose, 3 proteins were up-regulated and 30 down-regulated. Within the up-regulated proteins, two were identified as alcohol dehydrogenase and mitochondrial peroxyrredoxin-1, suggesting that they could play a significant role in the pathogenicity process. As for the 30 down-regulated proteins, 9 were identified being several of them involved in carbohydrate metabolism.</p> <p>Conclusions</p> <p>This study is the first report on proteomics on <it>D. seriata</it>. The proteomic data obtained will be important to understand the pathogenicity process. In fact, several of the identified proteins have been reported as pathogenicity factors in other phytopathogenic fungi. Moreover, this proteomic analysis supposes a useful basis for deepening into <it>D. seriata </it>knowledge and will contribute to the development of the molecular biology of this fungal strain as it has been demonstrated by cloning the gene <it>Prx</it>1 encoding mitochondrial peroxiredoxin-1 of <it>D. seriata </it>(the first gene to be cloned in this microorganism; data not shown).</p
Non-centralized control for flow-based distribution networks: a game-theoretical insight
© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/This paper solves a data-driven control problem for a flow-based distribution network with two objectives: a resource allocation and a fair distribution of costs. These objectives represent both cooperation and competition directions. It is proposed a solution that combines either a centralized or distributed cooperative game approach using the Shapley value to determine a proper partitioning of the system and a fair communication cost distribution. On the other hand, a decentralized non-cooperative game approach computing the Nash equilibrium is used to achieve the control objective of the resource allocation under a non-complete information topology. Furthermore, an invariant-set property is presented and the closed-loop system stability is analyzed for the non-cooperative game approach. Another contribution regarding the cooperative game approach is an alternative way to compute the Shapley value for the proposed specific characteristic function. Unlike the classical cooperative-games approach, which has a limited application due to the combinatorial explosion issues, the alternative method allows calculating the Shapley value in polynomial time and hence can be applied to large-scale problems.Peer ReviewedPostprint (author's final draft
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