Establecimiento de claves seguro mediante códigos sonoros en dispositivos móviles

El objetivo de este trabajo ha sido investigar el uso de canales sonoros para el intercambio de claves en teléfonos inteligentes. Para ello, se ha realizado un diseño y un análisis del problema a resolver, teniendo en cuenta factores como la necesidad de sincronización, los parámetros de escucha, la longitud de la clave que podemos obtener, los ataques a los que sería vulnerable el protocolo, la necesidad de cierta persistencia a nivel local, el uso de la nube, etc. Se ha realizado un análisis de tecnologías relacionadas, eligiendo aquellas que mejor se adaptan a los requisitos del problema y se ha implementado un prototipo capaz de realizar un intercambio de claves y autenticar mutuamente a un par de dispositivos, creando así un canal seguro a través del cual puedan comunicarse en el futuro, sin necesidad de que una tercera parte confiable que certifique la identidad de las partes.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Prueba de concepto de Autoridad de Certificación usando Computación Segura Multiparte

Este trabajo pretende analizar el paradigma de la Computación Segura Multiparte y sus posibles aplicaciones en el campo de la criptografía. Se plantea como modelo alternativo, más escalable y seguro al uso de módulos hardware de seguridad para aplicaciones que requieran de Terceras Partes Confiables. Concretamente, se ha integrado un protocolo de criptografía RSA multiparte con la librería certbuilder, para la creación de certificados X.509. De esta forma se asegura que la creación de los certificados raíz de la Infraestructura de Clave Pública se realiza de forma que la generación de claves y firma de éste se ejecute íntegramente sobre el sistema multiparte, con un modelo de tres partes que trabaja con circuitos aritméticos, sin que ninguna de ellas, de forma aislada, tenga posibilidad de comprometer la clave privada correspondiente. Para comprobar la viabilidad del sistema se han realizado pruebas de generación de certificados con diferentes longitudes de clave, siendo el proceso determinante la creación de las claves. Los elevados tiempos hacen que una aplicación como esta no sea asumible en otros escenarios, pero creemos que para el caso de la creación de los certificados raíz de una infraestructura de clave pública las garantías avanzadas de seguridad compensan el tiempo extra.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Cryptographic approaches for confidential computations in blockchain.

Blockchain technologies have been widely re- searched in the last decade, mainly because of the revolution they propose for different use cases. Moving away from centralized solutions that abuse their capabilities, blockchain looks like a great solution for integrity, transparency, and decentral- ization. However, there are still some problems to be solved, lack of privacy being one of the main ones. In this paper, we focus on a subset of the privacy area, which is confidentiality. Although users are increasingly aware of the importance of confidentiality, blockchain poses a barrier to the confidential treatment of data. We initiate the study of cryptographic confidential computing tools and focus on how these technologies can endow the blockchain with better capabilities, i.e., enable rich and versatile applications while pro- tecting users’ data. We identify Zero Knowledge Proofs, Fully Homomorphic Encryption, and Se- cure Multiparty Computation as good candidates to achieve this.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Interplay between arsenic and selenium biomineralization in Shewanella sp. O23S

Bacteria play crucial roles in the biogeochemical cycle of arsenic (As) and selenium (Se) as these elements are metabolized via detoxification, energy generation (anaerobic respiration) and biosynthesis (e.g. selenocysteine) strategies. To date, arsenic and selenium biomineralization in bacteria were studied separately. In this study, the anaerobic metabolism of As and Se in Shewanella sp. O23S was investigated separately and mixed, with an emphasis put on the biomineralization products of this process. Multiple analytical techniques including ICP-MS, TEM-EDS, XRD, Micro-Raman, spectmphotometry and surface charge (zeta potential) were employed. Shewanella sp. O23S is capable of reducing selenate (SeO42-) and selenite (SeO32-) to red Se(-S)(0), and arsenate (AsO43-) to arsenite (AsO33-). The release of H2S from cysteine led to the precipitation of AsS minerals: nanorod AsS and granular As2S3. When As and Se oxyanions were mixed, both As-S and Se(-S)(0) biominerals were synthesized. All biominerals were extracellular, amorphous and presented a negative surface charge (-24 to -38 mV). Kinetic analysis indicated the following reduction yields: SeO32- (90%), AsO43- (60%), and SeO42- (<10%). The mix of SeO32- with AsO43- led to a decrease in As removal to 30%, while Se reduction yield was unaffected (88%). Interestingly, SeO42- incubated with AsO43- boosted the Se removal (71%). The exclusive extracellular formation of As and Se biominerals might indicate an extracellular respiratory process characteristic of various Shewanella species and strains. This is the first study documenting a complex interplay between As and Se oxyanions: selenite decreased arsenate reduction, whereas arsenate stimulated selenate reduction. Further investigation needs to clarify whether Shewanella sp. O23S employs multi-substrate respiratory enzymes or separate, high affinity enzymes for As and Se oxyanion respiration.National Science Centre, Poland 2017/26/D/NZ1/00408Plan de Recuperacion, Transformacion y Resiliencia, through Universidad de Oviedo MU-21-UP2021-030 32892642Spanish Government European Commission RTI2018-099565-B-I00 PCI2019-111927-2Junta de Andalucia RNM-179University of Granada UCE-PP2016-05National Research, Development & Innovation Office (NRDIO) - Hungary NKFIH-471-3/202 European UnionNextGeneration EU, Ministerio de Universidade

Citrate Stabilizes Hydroxylapatite Precursors: Implications for Bone Mineralization

Mineralization of hydroxylapatite (HAp), the main inorganic phase in bone, follows nonclassical crystallization routes involving metastable precursors and is strongly influenced by organic macromolecules. However, the effect of small organic molecules such as citrate on the formation of HAp is not well constrained. Using potentiometric titration experiments and titration calorimetry, in combination with a multianalytical approach, we show that citrate stabilizes prenucleation species as well as a liquid-like calcium phosphate precursor formed before any solid phase nucleates in the system. The stabilization of a liquid-like precursor phase could facilitate infiltration into the cavities of the collagen fibrils during bone mineralization, explaining the enhancement of collagen-mediated mineralization by citrate reported in previous studies. Hence, citrate can influence bone mineralization way before any solid phase (amorphous or crystalline) is formed. We also show that HAp formation after amorphous calcium phosphate (ACP) in the absence and presence of citrate results in nanoplates of about 5-12 nm thick, elongated along the c axis. Such nanoplates are made up of HAp nanocrystallites with a preferred c axis orientation and with interspersed ACP. The nanoplatelet morphology, size, and preferred crystallographic orientation, remarkably similar to those of bone HAp nanocrystals, appear to be an intrinsic feature of HAp formed from an amorphous precursor. Our results challenge current models for HAp mineralization in bone and the role of citrate, offering new clues to help answer the long-standing question as to why natural evolution favored HAp as the mineral phase in bone

Citrate Stabilizes Hydroxylapatite Precursors: Implications for Bone Mineralization

This research was funded by the Spanish Government (grant nos. RTI2018.099565.B.I00 and CGL2015-64683-P), the European Commission (ERDF funds), the University of Granada ("Unidad Cientifica de Excelencia" UCE-PP201605), and the Junta de Andalucia (no. P11-RNM-7550 and research group RNM-179). The authors thank M. Abad and Haidour Benamin from CIC-UGR for their assistance during microscopy and NMR studies. C.R.A. thanks project A7 from SFB1214 (DFG-Deutsche Forschungsgemeinschaf) and Zukunftstkolleg (University of Konstanz).Mineralization of hydroxylapatite (HAp), the main inorganic phase in bone, follows nonclassical crystallization routes involving metastable precursors and is strongly influenced by organic macromolecules. However, the effect of small organic molecules such as citrate on the formation of HAp is not well constrained. Using potentiometric titration experiments and titration calorimetry, in combination with a multianalytical approach, we show that citrate stabilizes prenucleation species as well as a liquid-like calcium phosphate precursor formed before any solid phase nucleates in the system. The stabilization of a liquid-like precursor phase could facilitate infiltration into the cavities of the collagen fibrils during bone mineralization, explaining the enhancement of collagen-mediated mineralization by citrate reported in previous studies. Hence, citrate can influence bone mineralization way before any solid phase (amorphous or crystalline) is formed. We also show that HAp formation after amorphous calcium phosphate (ACP) in the absence and presence of citrate results in nanoplates of about 5−12 nm thick, elongated along the c axis. Such nanoplates are made up of HAp nanocrystallites with a preferred c axis orientation and with interspersed ACP. The nanoplatelet morphology, size, and preferred crystallographic orientation, remarkably similar to those of bone HAp nanocrystals, appear to be an intrinsic feature of HAp formed from an amorphous precursor. Our results challenge current models for HAp mineralization in bone and the role of citrate, offering new clues to help answer the long-standing question as to why natural evolution favored HAp as the mineral phase in bone.Spanish Government European Commission RTI2018.099565.B.I00 CGL2015-64683-PEuropean Commission European Commission Joint Research CentreUniversity of Granada ("Unidad Cientifica de Excelencia") UCE-PP2016-05Junta de Andalucia P11-RNM-7550 RNM-179DFG-Deutsche Forschungsgemeinschaf SFB1214Zukunftstkolleg (University of Konstanz

Private set intersection: A systematic literature review

Secure Multi-party Computation (SMPC) is a family of protocols which allow some parties to compute a function on their private inputs, obtaining the output at the end and nothing more. In this work, we focus on a particular SMPC problem named Private Set Intersection (PSI). The challenge in PSI is how two or more parties can compute the intersection of their private input sets, while the elements that are not in the intersection remain private. This problem has attracted the attention of many researchers because of its wide variety of applications, contributing to the proliferation of many different approaches. Despite that, current PSI protocols still require heavy cryptographic assumptions that may be unrealistic in some scenarios. In this paper, we perform a Systematic Literature Review of PSI solutions, with the objective of analyzing the main scenarios where PSI has been studied and giving the reader a general taxonomy of the problem together with a general understanding of the most common tools used to solve it. We also analyze the performance using different metrics, trying to determine if PSI is mature enough to be used in realistic scenarios, identifying the pros and cons of each protocol and the remaining open problems.This work has been partially supported by the projects: BIGPrivDATA (UMA20-FEDERJA-082) from the FEDER Andalucía 2014– 2020 Program and SecTwin 5.0 funded by the Ministry of Science and Innovation, Spain, and the European Union (Next Generation EU) (TED2021-129830B-I00). The first author has been funded by the Spanish Ministry of Education under the National F.P.U. Program (FPU19/01118). Funding for open access charge: Universidad de Málaga/CBU

Procedimiento de evaluación de riesgos laborales de un servicio de prevención ajeno

Las Evaluaciones de Riesgos Laborales son los métodos de evaluación llevados a cabo por los Técnicos de PRL con el objetivo de conseguir reducir y/o eliminar los riesgos existentes en las empresas a través de una buena gestión de la prevención. Estos métodos de evaluación requieren para su elaboración de un exhaustivo trabajo por parte del técnico así mismo, será necesario seguir una metodología establecida con carácter previo. A lo largo del presente trabajo, se revisará la metodología de la Evaluación de Riesgos Laborales así como sus elementos esenciales para finalizar analizando los procedimientos de toma de muestras y mediciones que se han llevado a cabo.Departamento de Ingeniería Química y Tecnología del Medio AmbienteMáster en Gestión de la Prevención de Riesgos Laborales, Calidad y Medio Ambient

A propósito de la regulación de las tasas judiciales en derecho justinianeo : nota sobre una constitución de Justiniano reguladora de las sportulae

El presente estudio tiene por objeto la reconstrucción de una ley de Justiniano, hoy perdida, reguladora de las sportulae que deben abonar los ciudadanos, no pertenecientes a las clases privilegiadas, a los distintos funcionarios que intervienen en las distintas actuaciones que se desarrollan en la cognitio extra ordinem.The purpose of the present investigation is the reconstruction of a lost Justinian’s Law, which regulates the sportulae that the no privileged citizens must pay the different public officials, who take part in the different stages of the procedure of the cognitio extra ordinem

International trade and gender equality : an applied approach

RESUMEN: Las situaciones de libre comercio y desigualdad de género y las políticas necesarias para superarlas han sido percibidas por la Unión Europea como una de las prioridades a las que se debe hacer frente de modo más activo. A lo largo del presente trabajo se investiga en el entorno europeo el posible efecto de la actividad exterior sobre la desigualdad de género, específicamente sobre la brecha salarial. Resalta la correlación negativa entre ambas variables, consiguiendo unos resultados más significativos cuando se restringe la muestra para los catorce países con mayor coeficiente de apertura. En este contexto el comercio internacional contribuye a favorecer a las mujeres, pero siendo necesarios los principios de la Unión Europea por tratar de consolidar la plena igualdad entre ambos sexos. ABSTRACT: Situations of free trade and gender inequality and politics necessary to overcome them have been perceived by the European Union as one of the priorities that must confront a more active way. Throughout this work, I investigate in the European Union the possible effect that the free trade about gender inequality, specifically on the wage gap. The correlation is negative between two indicators, and results are more significant when the sample is restricted for the fourteen countries with the highest openness coefficient. In this context, the international trade contributes to favoring to women, but principles of the European Union are necessary to try to consolidate full equality between both genders.Grado en Economí