Self-assembly of electroactive systems: from dimers to supramolecular polymers

Supramolecular aggregates and polymers are macromolecular entities that grow up by the non-covalent interaction of suitable monomeric units. In the search for new materials for optoelectronic applications through self-assembly, the control over the assembly process is one of the most sought-after characteristics. This control is usually achieved by a proper design of the monomeric structure and of the self-assembling motifs (H-bonds, π-stacking, dispersion forces or electrostatic interactions). The self-assembly of donor-acceptor supramolecular dimers formed by fullerene fragments (buckybowls) and tetrathiafulvalene (TTF)-based electron donors is first described in this presentation. The study relies on theoretical density functional theory (DFT) calculations and illustrates the difficulties in theoretically describing non-covalent interactions. In a following step, the polymerization mechanism and the structural properties of the supramolecular aggregates formed by monomeric units incorporating electroactive fragments are discussed on the basis of theoretical calculations. The discussion includes two types of monomeric units: 1) a bisurea macrocycle bearing electron-donor DMTTF moieties that leads to supramolecular polymers whose self-assembly can be electrochemically controlled, and 2) C3-symmetry conjugated systems decorated with peripheral amide groups endowed with paraffinic side chains that form helical π-stacked supramolecular polymers with defined chirality.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Improved Accuracy and Parallelism for MRRR-based Eigensolvers -- A Mixed Precision Approach

The real symmetric tridiagonal eigenproblem is of outstanding importance in numerical computations; it arises frequently as part of eigensolvers for standard and generalized dense Hermitian eigenproblems that are based on a reduction to tridiagonal form. For its solution, the algorithm of Multiple Relatively Robust Representations (MRRR) is among the fastest methods. Although fast, the solvers based on MRRR do not deliver the same accuracy as competing methods like Divide & Conquer or the QR algorithm. In this paper, we demonstrate that the use of mixed precisions leads to improved accuracy of MRRR-based eigensolvers with limited or no performance penalty. As a result, we obtain eigensolvers that are not only equally or more accurate than the best available methods, but also -in most circumstances- faster and more scalable than the competition

randUTV: A blocked randomized algorithm for computing a rank-revealing UTV factorization

This manuscript describes the randomized algorithm randUTV for computing a so called UTV factorization efficiently. Given a matrix $A$, the algorithm computes a factorization $A = UTV^{*}$, where $U$ and $V$ have orthonormal columns, and $T$ is triangular (either upper or lower, whichever is preferred). The algorithm randUTV is developed primarily to be a fast and easily parallelized alternative to algorithms for computing the Singular Value Decomposition (SVD). randUTV provides accuracy very close to that of the SVD for problems such as low-rank approximation, solving ill-conditioned linear systems, determining bases for various subspaces associated with the matrix, etc. Moreover, randUTV produces highly accurate approximations to the singular values of $A$. Unlike the SVD, the randomized algorithm proposed builds a UTV factorization in an incremental, single-stage, and non-iterative way, making it possible to halt the factorization process once a specified tolerance has been met. Numerical experiments comparing the accuracy and speed of randUTV to the SVD are presented. These experiments demonstrate that in comparison to column pivoted QR, which is another factorization that is often used as a relatively economic alternative to the SVD, randUTV compares favorably in terms of speed while providing far higher accuracy

Transición postfranquista a la monarquía parlamentaria y relaciones de clase: del desencanto programado a la social tecnocracia transnacional

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Evaluating Asymmetric Multicore Systems-on-Chip using Iso-Metrics

The end of Dennard scaling has pushed power consumption into a first order concern for current systems, on par with performance. As a result, near-threshold voltage computing (NTVC) has been proposed as a potential means to tackle the limited cooling capacity of CMOS technology. Hardware operating in NTV consumes significantly less power, at the cost of lower frequency, and thus reduced performance, as well as increased error rates. In this paper, we investigate if a low-power systems-on-chip, consisting of ARM's asymmetric big.LITTLE technology, can be an alternative to conventional high performance multicore processors in terms of power/energy in an unreliable scenario. For our study, we use the Conjugate Gradient solver, an algorithm representative of the computations performed by a large range of scientific and engineering codes.Comment: Presented at HiPEAC EEHCO '15, 6 page

How exogenous factors redirect voter preferences: the case of Italy and Lega Nord

The current rise of far right populist parties in Europe has touched the Italian political scene during the 2018 national elections, when Lega Nord (Northern League) reached 17.35 percent of support from all over the country. This thesis will strive to understand how it was possible that a former regional party like Lega was able to exponentially increase its electoral support, especially in the traditionally antagonistic Center and South of Italy. In fact, the evolution of Lega through its foundation under Umberto Bossi’s leadership until the leadership of the current Minister of Interior Matteo Salvini shows patterns that are worth researching. To establish a link between the change of discourse and the redirection of preferences of Italian voters, especially the ones from the Central and Southern regions, critical discourse analysis was applied to speeches given by Bossi and Salvini in the time span between 2007-2018. In addition, electoral data was used as supporting evidence to trace Lega voting patterns of Italians, focusing on the specific regions, between 2008 and 2018. The main findings of this work show that there is a plausible link between the presupposed change of the “self-other” representation and the increase of Lega electoral share in the Central and Southern regions. Relying on the Lega Nord scholarship and the data collected from Bossi’s speeches, it was possible to determine that the original identity of supporters of the party was built through their differentiation and opposition towards the Center and the South of Italy, often with uncouth ranting directed to the Southerners. This process allowed the creation of a “self-other,” that is a Northerners against Southerners dichotomy. Nevertheless, this articulation was drastically changed by Salvini. The politician was able to switch the “other” representation to an exogenous “enemy,” that is the migrant. Moreover, this change of discourse started almost at the same time of the beginning of the 2013 migrant crisis. The change of discourse by Salvini was reflected in the voting patterns of Southern Italians, that were able to put behind the past insults by Lega and redirect their votes in a united front against the most modern perceived “other.”https://www.ester.ee/record=b5242341*es

Don Tomás Albán, printer in Madrid at the beginning of the nineteenth century

En este artículo se efectúa una reconstrucción provisional de la trayectoria de don Tomás Albán, impresor que trabajó en Madrid a principios del siglo XIX. Con su conducta personal y mediante sus impresiones, se significó política e ideológicamente por su adhesión a los franceses en la guerra de la Independencia y al régimen liberal durante el Trienio 1820 a 1823. Albán terminó traspasando su establecimiento durante la restauración absolutista.In this article a provisional reconstruction of the trajectory of Don Tomás Albán is carried out, printer who worked in Madrid at the beginning of the 19th century. Through his personal conduct and through his impressions, he was politically and ideologically signified by his adherence to the French in the War of Independence and to the liberal regime during the Triennium 1820 to 1823. Albán ended up transcending his establishment during the absolutist restoration

Neuroinflammation: friend or foe in Alzheimer's disease?:Modulating the immune system as therapeutic strategy

Alzheimer’s disease (AD) is a devastating neurodegenerative disease and the most common form of dementia that currently affects 55 million people globally. AD is characterized by loss of memory, changes in mood and behavior and the inability to perform daily tasks. Despite decades of exhaustive research, no successful treatment has been discovered for AD. Besides the characteristic pathology observed in the AD brain, inflammation of the brain (known as neuroinflammation) and the involvement of the immune system have emerged as new therapeutic venues. The main objective of this thesis was to modulate the immune system as strategy to ameliorate cognitive deficits and AD-related neuropathology. To this end, we focused on the signaling of a specific protein, TNF-α, which plays a key role in the orchestration of the immune response. TNF-α can activate two different signaling pathways and exert opposing functions: activation of one pathway leads to inflammation and cell death whereas activation of the second pathway leads to cell survival and neuroprotection.In this thesis, we discovered that activating the neuroprotective signaling pathway of TNF-α in different AD mouse models results in a significant improvement of cognitive functions as well as a drastic reduction in AD neuropathology. Thus, modulation of TNF-α signaling seems like an effective strategy for the treatment of AD.This thesis has provided a more in depth understanding on the role, mechanisms and effects of modulating the immune system in AD and proposed new potential therapeutic strategies that can be explored in the future for the treatment of AD

La estrategia de la oferta en la sociedad neocapitalista de consumo: génesis y praxis de la investigacion motivacional

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