A Small Platform for Astrophysical Research Based on the UPM-Sat 1 Satellite of the Universidad Politécnica de Madrid

UPM-Sat 1 is a small scientific, in-orbit demonstration, educational satellite which has been designed, built, tested, integrated, launched and operated by a team of professors, students, and auxiliary personnel belonging to the Universidad Politécnica de Madrid (UPM). After completion of UPM-Sat 1 Mission a new small satellite, UPM-Sat 2, oriented to low-Earth-orbit scientific mission has been designed. In this paper the different subsystems of UPM-Sat 1 are described and the main characteristics of the second small satellite UPM-Sat 2 are outlined

On the galloping instability of two-dimensional bodies having elliptical cross sections.

Galloping, also known as Den Hartog instability, is the large amplitude, low frequency oscillation of a structure in the direction transverse to the mean wind direction. It normally appears in the case of bodies with small stiffness and structural damping, when they are placed in a flow provided the incident velocity is high enough. Galloping depends on the slope of the lift coefficient versus angle of attack curve, which must be negative. Generally speaking this implies that the body is stalled after boundary layer separation, which, as it is known in non-wedged bodies, is a Reynolds number dependent phenomenon. Wind tunnel experiments have been conducted aiming at establishing the characteristics of the galloping motion of elliptical cross-section bodies when subjected to a uniform flow, the angles of attack ranging from 0° to 90°. The results have been summarized in stability maps, both in the angle of attack versus relative thickness and in the angle of attack versus Reynolds number planes, where galloping instability regions are identified

TÉCNICAS INTELIGENTES, AGENTES ADAPTATIVOS Y REPRESENTACIONES ONTOLÓGICAS EN SISTEMAS DE DETECCIÓN DE INTRUSOS

RESUMEN La seguridad Informática requiere una optimización permanente de los mecanismos de protección y estrategias que permitan prevenir ataques en las redes y sistemas de información. El proceso de monitoreo de eventos que ocurren en un sistema o en una red a partir de patrones y firmas de posibles ataques se conoce como Sistema de Detección de Intrusos (IDS). Los IDS han escalado significativamente al punto de focalizarse en modelos basados en prevención más que en corrección, estos sistemas monitorean tráfico utilizando un conjunto de firmas para detectar actividades malignas, reportar incidentes o tomar acciones correctivas; pero cualquier cambio insertado en el patrón de un ataque, puede comprometer el sistema y evitar que la tecnología subyacente de detección o prevención sea insuficiente. En los últimos años se han planteado diferentes modelos basados en técnicas de Inteligencia Artificial que pueden ayudar a la generación automática de nuevas firmas y detectar nuevos patrones de ataque sin la intervención humana. Algunas investigaciones presentan técnicas como Redes Neuronales, Algoritmos Genéticos, Razonamiento Basado en Casos, árboles de decisión, Lógica Difusa entre otras, aplicadas a la Detección de Intrusos, además de arquitecturas basadas en Agentes Inteligentes sobre IDS Distribuidos incorporando así capacidades de autonomía, reactividad, pro actividad, movilidad y racionalidad. Este artículo es el resultado de un estudio del estado del arte de las diferentes estrategias inteligentes en IDS. Además la introducción de modelos de cooperación a partir de Agentes adaptativos y de representaciones ontológicas en los Sistemas de Detección de Intrusos Distribuidos, adicionalmente se plantean los elementos de una investigación en curso donde se incorporan estos métodos.PALABRAS CLAVE: Sistemas de Detección de Intrusos, Detección de Intrusos Inteligente, Agentes Inteligentes, Seguridad en Redes, Representaciones Ontológicas y Semánticas Conglomerados.   ABSTRACT Security Computing requires a permanent optimization in protection mechanisms and strategies that allow preventing attacks in the networks and information systems. The event monitoring process that happens in a system or a network using patterns or signs is known like Intrusion Detection System (IDS).    The IDS have been focused more in prevention models than correction models; these systems tests traffic using a set of signs to detect malicious activities, report incidents o take correction actions; but, any change inserted in the attack pattern can compromise the system and avoid the underlying technology and make insufficient the Intrusion Detection. Over the years different models based in Artificial Intelligence techniques have been considered to help the automatic signs and patterns generation without human intervention.     Some     researching     projects     present Neuronal Networks, Genetic Algorithms, Case Based Reasoning, decision trees, Fuzzy logic applied to the Intrusion Detection; additionally using Intelligent and Mobile Agents architectures over Distributed IDS incorporating autonomy, reactivity, pro activity, mobility and    rationality    capabilities.     This    paper    is    result    of studying state of art of multiples intelligent strategies in IDS and cooperation models using Agents and ontology representation in Intrusion Detection. This paper complements elements in a course research considering integrating these methods.KEYWORDS: Intrusion Detection Systems, Intelligent Intrusion Detection, Intelligent Agents, Network Security, Ontology and Semantic representations

Increased circulating microRNAs miR-342-3p and miR-21-5p in natural sheep prion disease

Scrapie is a transmissible spongiform encephalopathy (TSE), or prion disease, of sheep and goats. As no simple diagnostic tests are yet available to detect TSEs in vivo, easily accessible biomarkers could facilitate the eradication of scrapie agents from the food chain. To this end, we analysed by quantitative reverse transcription PCR a selected set of candidate microRNAs (miRNAs) from circulating blood plasma of naturally infected, classical scrapie sheep that demonstrated clear scrapie symptoms and pathology. Significant scrapie-associated increase was repeatedly found for miR-342-3p and miR-21-5p. This is the first demonstration, to our knowledge, of circulating miRNA alterations in any animal suffering from TSE. Genome-wide expression studies are warranted to investigate the true depth of miRNA alterations in naturally occurring TSEs, especially in presymptomatic animals, as the presented study demonstrates the potential feasibility of miRNAs as circulating TSE biomarkers

TÉCNICAS INTELIGENTES, AGENTES ADAPTATIVOS Y REPRESENTACIONES ONTOLÓGICAS EN SISTEMAS DE DETECCIÓN DE INTRUSOS

RESUMEN La seguridad Informática requiere una optimización permanente de los mecanismos de protección y estrategias que permitan prevenir ataques en las redes y sistemas de información. El proceso de monitoreo de eventos que ocurren en un sistema o en una red a partir de patrones y firmas de posibles ataques se conoce como Sistema de Detección de Intrusos (IDS). Los IDS han escalado significativamente al punto de focalizarse en modelos basados en prevención más que en corrección, estos sistemas monitorean tráfico utilizando un conjunto de firmas para detectar actividades malignas, reportar incidentes o tomar acciones correctivas; pero cualquier cambio insertado en el patrón de un ataque, puede comprometer el sistema y evitar que la tecnología subyacente de detección o prevención sea insuficiente. En los últimos años se han planteado diferentes modelos basados en técnicas de Inteligencia Artificial que pueden ayudar a la generación automática de nuevas firmas y detectar nuevos patrones de ataque sin la intervención humana. Algunas investigaciones presentan técnicas como Redes Neuronales, Algoritmos Genéticos, Razonamiento Basado en Casos, árboles de decisión, Lógica Difusa entre otras, aplicadas a la Detección de Intrusos, además de arquitecturas basadas en Agentes Inteligentes sobre IDS Distribuidos incorporando así capacidades de autonomía, reactividad, pro actividad, movilidad y racionalidad. Este artículo es el resultado de un estudio del estado del arte de las diferentes estrategias inteligentes en IDS. Además la introducción de modelos de cooperación a partir de Agentes adaptativos y de representaciones ontológicas en los Sistemas de Detección de Intrusos Distribuidos, adicionalmente se plantean los elementos de una investigación en curso donde se incorporan estos métodos.PALABRAS CLAVE: Sistemas de Detección de Intrusos, Detección de Intrusos Inteligente, Agentes Inteligentes, Seguridad en Redes, Representaciones Ontológicas y Semánticas Conglomerados.   ABSTRACT Security Computing requires a permanent optimization in protection mechanisms and strategies that allow preventing attacks in the networks and information systems. The event monitoring process that happens in a system or a network using patterns or signs is known like Intrusion Detection System (IDS).    The IDS have been focused more in prevention models than correction models; these systems tests traffic using a set of signs to detect malicious activities, report incidents o take correction actions; but, any change inserted in the attack pattern can compromise the system and avoid the underlying technology and make insufficient the Intrusion Detection. Over the years different models based in Artificial Intelligence techniques have been considered to help the automatic signs and patterns generation without human intervention.     Some     researching     projects     present Neuronal Networks, Genetic Algorithms, Case Based Reasoning, decision trees, Fuzzy logic applied to the Intrusion Detection; additionally using Intelligent and Mobile Agents architectures over Distributed IDS incorporating autonomy, reactivity, pro activity, mobility and    rationality    capabilities.     This    paper    is    result    of studying state of art of multiples intelligent strategies in IDS and cooperation models using Agents and ontology representation in Intrusion Detection. This paper complements elements in a course research considering integrating these methods.KEYWORDS: Intrusion Detection Systems, Intelligent Intrusion Detection, Intelligent Agents, Network Security, Ontology and Semantic representations

Carbon-encapsulated iron nanoparticles as reusable adsorbents for micropollutants removal from water

Adsorption represents the most plausible technology for micropollutants removal from water nowadays. Nevertheless, the regeneration of the saturated carbon materials is still an important challenge, being these solids in practice commonly disposed. This work aims at overcoming this issue by using innovative carbonencapsulated iron nanoparticles (CE-nFe). This material was synthesized by a low-cost and green method viz. hydrothermal carbonization (HTC), using olive mill wastewater as carbonaceous source. The solid was fully characterized by different techniques (magnetic properties, elemental analyses, N2-sorption isotherms, pHPZC, ICP, XRD and TEM). It showed a clear core-shell structure of around 40 nm in diameter. The core was mainly formed by zero-valent iron and the shell by graphitized carbon. Accordingly, it showed an essentially mesoporous structure, with a specific surface area of 169 m2 g−1 , and a clear hydrophobic character (pHPZC = 10). Its adsorption performance was investigated using three relevant micropollutants (diclofenac (DCF), sulfamethoxazole (SMX) and metronidazole (MNZ)). A very fast removal of the micropollutants was achieved (30 min at the most, with rate constants in the range of 0.11–0.41 g mg−1 min−1 ). The adsorption isotherms revealed the vertical packing of the adsorbate molecules onto the adsorbent active centers, being the data successfully described by the GAB model. The saturated adsorbents were effectively regenerated by heterogeneous Fenton oxidation, taking advantage of the iron core of CE-nFe and the opened mesoporous carbon shell. The regeneration efficiency increased with increasing the operating temperature (25–75 ◦C) and contact time (1–4 h), as well as the H2O2 dose up to 6 g L-1. The micropollutant nature affected the adsorbent regeneration yield in the order: SMX > DCF > MNZ, consistent with their reactivity towards Fenton oxidationThis research has been supported by the Spanish MINECO through the project CTM-2016-76454-R and by the CM through the project P2018/EMT-4341. M. Munoz and J. Nieto-Sandoval thank the Spanish MINECO for the Ramón y Cajal postdoctoral contract (RYC-2016-20648) and the FPI predoctoral grant (BES-2017-081346), respectivel

Supercritical CO2 and subcritical water technologies for the production of bioactive extracts from sardine (Sardina pilchardus) waste

The valorization of sardine (Sardina pilchardus) waste (SW) from a canning facility has been investigated within a biorefining approach. Sequential fractionation of SW into its constituents has been carried out using green solvents such as supercritical carbon dioxide (SCCO2) and subcritical water (sCW). The lipid fraction has been isolated through supercritical fluid extraction (SFE) with SCCO2 at 250 bar and 40 °C, yielding 20.3 ± 0.2 g oil/100 g SW with up to 17.2 %wt. omega-3 polyunsaturated fatty acids (PUFAs). Aiming at the protein fraction, sCW extraction/hydrolysis has been carried out at different temperatures (90, 140, 190 and 250 °C), using both SW and defatted sardine waste (DSW) from SFE experiments. Previous defatting increased protein recovery and purity. Bioactive properties of the fish protein hydrolysates (FPHs) obtained were affected by the extraction temperature. The highest antioxidant activity and in vitro antiproliferative effect were found in the extracts obtained at 250 °C.FCT/MCTES (UIDB/QUI/50006/2020), and Fundação para a Ciência e a Tecnologia through project PTDC/ASP-PES/28399/2017 and grants IF/01146/2015 and SFRH/BD/116002/201

Discovery of the elusive carbonic acid (HOCOOH) in space

After a quarter century since the detection of the last interstellar carboxylic acid, acetic acid (CH$_3$COOH), we report the discovery of a new one, the cis-trans form of carbonic acid (HOCOOH), toward the Galactic Center molecular cloud G+0.693-0.027. HOCOOH stands as the first interstellar molecule containing three oxygen atoms and also the third carboxylic acid detected so far in the interstellar medium. Albeit the limited available laboratory measurements (up to 65 GHz), we have also identified several pairs of unblended lines directly in the astronomical data (between 75-120 GHz), which allowed us to slightly improve the set of spectroscopic constants. We derive a column density for cis-trans HOCOOH of $N$ = (6.4 $\pm$ 0.4) $\times$ 10$^{12}$ cm$^{-2}$, which yields an abundance with respect to molecular H$_2$ of 4.7 $\times$ 10$^{-11}$. Meanwhile, the extremely low dipole moment (about fifteen times lower) of the lower-energy conformer, cis-cis HOCOOH, precludes its detection. We obtain an upper limit to its abundance with respect to H$_2$ of $\leq$ 1.2 $\times$10$^{-9}$, which suggests that cis-cis HOCOOH might be fairly abundant in interstellar space, although it is nearly undetectable by radio astronomical observations. We derive a cis-cis/cis-trans ratio $\leq$ 25, consistent with the smaller energy difference between both conformers compared with the relative stability of trans- and cis-formic acid (HCOOH). Finally, we compare the abundance of these acids in different astronomical environments, further suggesting a relationship between the chemical content found in the interstellar medium and the chemical composition of the minor bodies of the Solar System, which could be inherited during the star formation process.Comment: Accepted for publication in The Astrophysical Journa

Interstellar detection of O-protonated carbonyl sulfide, HOCS+

We present the first detection in space of O-protonated carbonyl sulfide (\ch{HOCS+}), in the midst of an ultradeep molecular line survey toward the G+0.693-0.027 molecular cloud. From the observation of all $K$$_a$ = 0 transitions ranging from $J$$_{lo}$ = 2 to $J$$_{lo}$ = 13 of \ch{HOCS+} covered by our survey, we derive a column density of $N$ = (9 $\pm$ 2)$\times$10$^{12}$ cm$^{-2}$, translating into a fractional abundance relative to H$_2$ of $\sim$7$\times$10$^{-11}$. Conversely, the S-protonated \ch{HSCO+} isomer remains undetected, and we derive an upper limit to its abundance with respect to H$_2$ of $\leq$3$\times$10$^{-11}$, a factor of $\geq$2.3 less abundant than \ch{HOCS+}. We obtain a \ch{HOCS+}/OCS ratio of $\sim$2.5$\times$10$^{-3}$, in good agreement with the prediction of astrochemical models. These models show that one of the main chemical routes to the interstellar formation of \ch{HOCS+} is likely the protonation of OCS, which appears to be more efficient at the oxygen end. Also, we find that high values of cosmic-ray ionisation rates (10$^{-15}$-10$^{-14}$ s$^{-1}$) are needed to reproduce the observed abundance of \ch{HOCS+}. In addition, we compare the O/S ratio across different interstellar environments. G+0.693-0.027 appears as the source with the lowest O/S ratio. We find a \ch{HOCO+}/\ch{HOCS+} ratio of $\sim$31, in accordance with other O/S molecular pairs detected toward this region and also close to the O/S solar value ($\sim$37). This fact indicates that S is not significantly depleted within this cloud due to the action of large-scale shocks, unlike in other sources where S-bearing species remain trapped on icy dust grains.Comment: Forthcoming paper in The Astrophysical Journal (in press