Anonimato en blockchain: Monero

Blockchain is a decentralized database that records blocks of information and links one block to the previous ones by means of cryptographic functions. In this way, information integrity is guaranteed. So far, the main application of blockchains have been monetary transactions, and usually each blockchain uses its own currency. The first and best-known of these currencies, better known as cryptocurrencies, was Bitcoin. One of the advantages of using Bitcoin against traditional monetary systems is that it does not require the presence of a central entity, such a bank, in charge of verifying data and validating transactions. In a blockchain, its own users are responsible for that and make use of a consensus protocol to approve or reject transactions. Despite it, this cryptocurrency exhibits many problems such as the lack of anonymity in the transactions. For this reason, the scientific community has developed other approaches in order to overcome Bitcoin limitations. Monero is a blockchain created in 2014, which uses advanced cryptography in order to provide a high degree of anonymity to its users. Its main goal is to prevent third parties from linking a transaction with its sender and its receiver. With this purpose, it makes use of several security mechanisms such as ring signature, the division of the expense and two pairs of public-private keys or RingCT, a feature that allows you to hide the amount of money sent in transactions. A recent study analyzed the likelihood of cancelling anonymity provided by the ring signature. As a consequence, a new feature named RingCT was added to Monero, which allows the hiding of the amount of cryptocurrency sent in a specific transaction. The goals of this work are twofold. On the one hand, to analyze the performance of Monero in a theoretical and practical way, by running a test blockchain. On the other hand, we aim at analyzing by means of Machine Learning algorithms under which circumstances an attacker can overcome security mechanisms such as RingCT and break Monero’s anonymity

Análisis crítico del concepto de individuo liberal desde una posición personalista

El concepte d’individu construeix els fonaments antropològics dels principis polítics de justícia liberal. Malgrat ser, a priori, un discurs que pretén oferir justícia per tothom, realment està legitimant un model polític i econòmic injust, que genera greus desigualtats socials. L’objectiu de l’article és, en primer lloc, analitzar aquestes bases antropològiques del capitalisme i, en segon lloc, recuperar el concepte de persona propi de la tradició personalista del segle XX, sovint oblidat, per replantejar-lo com una alternativa vàlida i vigent.The concept of individual builds the anthropological foundations of the political principles of liberal justice. Despite being, a priori, a discourse that aims to offer justice for everyone, it is actually legitimizing an unjust political and economic model, which generates serious social inequalities. The aim of the article is, firstly, to analyze these anthropological bases of capitalism and, secondly, to recover the concept of person from the personalist tradition of the 20th century, often forgotten, to reframe it as a valid and current alternative.El concepto de individuo construye los cimientos antropológicos de los principios políticos de justicia liberal. A pesar de ser, a priori, un discurso que pretende ofrecer justicia para todo el mundo, realmente está legitimando un modelo político y económico injusto, que genera graves desigualda-des sociales. El objetivo del artículo es, en primer lugar, analizar estas bases antropológicas del capitalismo y, en segundo lugar, recuperar el concepto de persona propio de la tradición persona-lista del siglo XX, a menudo olvidado, para replantearlo críticamente como una alternativa válida y vigente

A Linux Kernel Scheduler Extension for Multi-core Systems

The Linux kernel is mostly designed for multi-programed environments, but high-performance applications have other requirements. Such applications are run standalone, and usually rely on runtime systems to distribute the application's workload on worker threads, one per core. However, due to current OSes limitations, it is not feasible to track whether workers are actually running or blocked due to, for instance, a requested resource. For I/O intensive applications, this leads to a significant performance degradation given that the core of a blocked thread becomes idle until it is able to run again. In this paper, we present the proof-of-concept of a Linux kernel extension denoted User-Monitored Threads (UMT) which tackles this problem. Our extension allows a user-space process to be notified of when the selected threads become blocked or unblocked, making it possible for a runtime to schedule additional work on the idle core. We implemented the extension on the Linux Kernel 5.1 and adapted the Nanos6 runtime of the OmpSs-2 programming model to take advantage of it. The whole prototype was tested on two applications which, on the tested hardware and the appropriate conditions, reported speedups of almost 2x.Comment: 10 pages, 5 figures, conferenc

El trademarketing y su relación con las ventas en productos de consumo masivo en el canal tradicional de la empresa Molitalia en la ciudad de Trujillo en el año 2021

La presente tesis tuvo como objetivo poder determinar la relación entre el trademarketing y su influencia en las ventas de la empresa “MOLITALIA” en la ciudad de Trujillo, en el año 2021. Se trata de un estudio de tipo correlacional-descriptiva de corte trasversal. Se aplicó una encuesta para la medición de las variables, trademarketing y ventas, está encuesta está relaborada por 20 preguntas, que contienen ocho dimensiones: merchandising, visual merchandising, material POP, activaciones BTL, abastecimiento y distribución, valor de venta, incremento de ventas, valor percibido. Existe 5 opciones de respuesta para cada un a de las preguntas planteadas que fueron aplicadas a través de la escala de Liket. Se trabajó con una muestra de 208 personas, todos clientes de la empresa “MOLITALIA”, estos clientes en su totalidad estuvieron enfocados en el canal tradicional mayorista. El procesamiento estadístico de los datos se realizó con el paquete de Sofware estadístico SPSS en su versión 2.0. El instrumento fue validado por docentes de la Universidad Privada del Norte, quienes son especialistas en el tema. Los resultados se presentan a través de figuras y cuadros, con la finalidad de hacer una representación gráfica de los resultados obtenidos. Finalmente se determinó que existe una relación entre trademarketing y ventas, además el coeficiente de correlación Spearman, confirma lo anteriormente mencionado, considerando así, la relación de ambas variables

A Linux kernel scheduler extension for multi-core systems

©2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The Linux kernel is mostly designed for multi-programed environments, but high-performance applications have other requirements. Such applications are run standalone, and usually rely on runtime systems to distribute the application's workload on worker threads, one per core. However, due to current OSes limitations, it is not feasible to track whether workers are actually running or blocked due to, for instance, a requested resource. For I/O intensive applications, this leads to a significant performance degradation given that the core of a blocked thread becomes idle until it is able to run again. In this paper, we present the proof-of-concept of a Linux kernel extension denoted User-Monitored Threads (UMT) which tackles this problem. Our extension allows a user-space process to be notified of when the selected threads become blocked or unblocked, making it possible for a runtime to schedule additional work on the idle core. We implemented the extension on the Linux Kernel 5.1 and adapted the Nanos6 runtime of the OmpSs-2 programming model to take advantage of it. The whole prototype was tested on two applications which, on the tested hardware and the appropriate conditions, reported speedups of almost 2x.This project is supported by the European Union’s Horizon 2021 research and innovation programme under the grant agreement No 754304 (DEEP-EST), the Ministry of Economy of Spain through the Severo Ochoa Center of Excellence Program (SEV-2015-0493), by the Spanish Ministry of Science and Innovation (contract TIN2015-65316-P) and by the Generalitat de Catalunya (2017-SGR-1481).Peer ReviewedPostprint (author's final draft

An ontology for drug-drug interactions

Proceedings of: The 6th International Workshop on Semantic Web Applications and Tools for Life Sciences (SWAT4LS 2013). Took place 2013, December 11-12, in Edinburgh, UK. The evnt Web site http://www.swat4ls.org/workshops/edinburgh2013/Drug-drug interactions form a significant risk group for adverse effects associ-ated with pharmaceutical treatment. These interactions are often reported in the literature, however, they are sparsely represented in machine-readable re-sources, such as online databases, thesauri or ontologies. These knowledge sources play a pivotal role in Natural Language Processing (NLP) systems since they provide a knowledge representation about the world or a particular do-main. While ontologies for drugs and their effects have proliferated in recent years, there is no ontology capable of describing and categorizing drug-drug in-teractions. Moreover, there is no artifact that represents all the possible mecha-nisms that can lead to a DDI. To fill this gap we propose DINTO, an ontology for drug-drug interactions and their mechanisms. In this paper we describe the classes, relationships and overall structure of DINTO. The ontology is free for use and available at https://code.google.com/p/dinto/This work was supported by the Regional Government of Madrid under the Research Network MA2VICMR [S2009/TIC-1542], by the Spanish Ministry of Education under the project MULTIMEDICA [TIN2010-20644-C03-01] and by the European Commission Seventh Framework Programme under the project TrendMiner_Enlarged (EU FP7-ICT 612336).Publicad

Growth-rate-dependent and nutrient-specific gene expression resource allocation in fission yeast

Cellular resources are limited and their relative allocation to gene expression programmes determines physiological states and global properties such as the growth rate. Here, we determined the importance of the growth rate in explaining relative changes in protein and mRNA levels in the simple eukaryote Schizosaccharomyces pombe grown on non-limiting nitrogen sources. Although expression of half of fission yeast genes was significantly correlated with the growth rate, this came alongside wide-spread nutrient-specific regulation. Proteome and transcriptome often showed coordinated regulation but with notable exceptions, such as metabolic enzymes. Genes positively correlated with growth rate participated in every level of protein production apart from RNA polymerase II-dependent transcription. Negatively correlated genes belonged mainly to the environmental stress response programme. Critically, metabolic enzymes, which represent ∼55-70% of the proteome by mass, showed mostly condition-specific regulation. In summary, we provide a rich account of resource allocation to gene expression in a simple eukaryote, advancing our basic understanding of the interplay between growth-rate-dependent and nutrient-specific gene expression

A Linux Kernel Scheduler Extension for Multi-Core Systems

International audienc

Experimental and Theoretical Studies on alfa-In2Se3 at High Pressure

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://doi.org/10.1021/acs.inorgchem.8b00778[EN] alpha(R)-In2Se3 has been experimentally and theoretically studied under compression at room temperature by means of X-ray diffraction and Raman scattering measurements as well as by ab initio total-energy and lattice-dynamics calculations. Our study has confirmed the alpha (R3m) -> beta' (C2/m) ? beta (R (3) over barm) sequence of pressure-induced phase transitions and has allowed us to understand the mechanism of the monoclinic C2/m to rhombohedral R (3) over barm phase transition. The monoclinic C2/m phase enhances its symmetry gradually until a complete transformation to the rhombohedral R (3) over barm structure is attained above 10-12 GPa. The second-order character of this transition is the reason for the discordance in previous measurements. The comparison of Raman measurements and lattice-dynamics calculations has allowed us to tentatively assign most of the Raman-active modes of the three phases. The comparison of experimental results and simulations has helped to distinguish between the different phases of In2Se3 and resolve current controversies.The authors acknowledge financial support from Spanish government MINECO, the Spanish Agencia Estatal de Investigacion (AEI), and Fondo Europeo de Desarrollo Regional (FEDER) under Grants No. MAT2016-75586-C4-1/2/3-P and MAT2015-71070-REDC.Vilaplana Cerda, RI.; Gallego-Parra, S.; Jorge-Montero, A.; Rodríguez-Hernández, P.; Muñoz, A.; Errandonea, D.; Segura, A.... (2018). Experimental and Theoretical Studies on alfa-In2Se3 at High Pressure. Inorganic Chemistry. 57:8241-8252. https://doi.org/10.1021/acs.inorgchem.8b00778S824182525