Mesoporous niobium oxide for dehydration of D-xylose into furfural

Se ha demostrado que el óxido de niobio mesoporoso es un catalizador eficaz para la deshidratación de D-xilosa a furfural, alcanzando una conversión del 92% y un rendimiento de furfural 49,3% a 170º C y 90 minutos. La lixiviación de Nb, determinada por ICP-MS, era inferior al 0,5% en peso de la concentración de Nb inicial, confirmando de este modo la estabilidad del catalizador ácido sólido.El furfural posee un gran potencial como molécula plataforma de origen renovable para la síntesis de una alta variedad de compuestos químicos. Se obtiene mediante la deshidratación de pentosas, principalmente a partir de D-xilosa, proceso catalizado por ácidos minerales en fase homogénea. Por tanto, dentro de la química verde y la búsqueda de sostenibilidad de los procesos catalíticos, es necesaria su sustitución por catalizadores sólidos ácidos que sean tolerantes al agua, ya que es el disolvente más utilizado para esta reacción. El óxido de niobio posee propiedades ácidas y es insoluble en agua, pero su superficie específica es muy baja. Por lo tanto, resulta muy interesante la síntesis de un óxido de niobio mesoporoso para emplearlo como catalizador en esta reacción. En este trabajo, se ha sintetizado un Nb2O5 mesoporoso y se ha evaluado su comportamiento catalítico en la obtención de furfural a partir de D-xilosa.Spanish Ministry of Science and Innovation (ENE2009-12743-C04-03 project)Junta de Andalucía (P09-FQM-5070).Ministry of Science and Innovation for the financial support under the Program Ramón y Cajal (RYC-2008-03387)

An Agent Oriented Analysis and Modeling of Airborne Capabilities for Trajectory Based Operations

Current and future air traffic is requiring new procedures and systems to achieve a greater automation of air-traffic operations. Particular difficulty presents the automation of arrival air-traffic operations in terminal areas due to aircraft speeds and environment variability into a delimited airspace where multiple aircraft converge. Several projects have proposed guidelines to implement new operational concepts as well as airborne and ground systems to carry out corresponding procedures. Developing procedures and systems are closely related. Therefore, usually it requires to analyze and to design them in a combined manner. In this paper we present an agent-oriented analysis and modeling of airborne systems capabilities to perform automated arrival and approach procedures based on user preference trajectories. A detailed architecture model of airborne capabilities is achieved through a methodological analysis of an arrival traffic scenario within the trajectory based operations paradigm

Generic multisensor multitarget bias estimation architecture

Current bias estimation algorithms for air traffic control (ATC) surveillance are focused on radar sensors, but the integration of new sensors (especially automatic dependent surveillance-broadcast and wide area multilateration) demands the extension of traditional procedures. This study describes a generic architecture for bias estimation applicable to multisensor multitarget surveillance systems. It consists on first performing bias estimations using measurements from each target, of a subset of sensors, assumed to be reliable, forming track bias estimations. All track bias estimations are combined to obtain, for each of those sensors, the corresponding sensor bias. Then, sensor bias terms are corrected, to subsequently calculate the target or sensor-target pair specific biases. Once these target-specific biases are corrected, the process is repeated recursively for other sets of less reliable sensors, assuming bias corrected measures from previous iterations are unbiased. This study describes the architecture and outlines the methodology for the estimation and the bias estimation design processes. Then the approach is validated through simulation, and compared with previous methods in the literature. Finally, the study describes the application of the methodology to the design of the bias estimation procedures for a modern ATC surveillance application, specifically for off-line assessment of ATC surveillance performance

A 4D Trajectory Negotiation Protocol for Arrival and Approach Sequencing

Future 4D TBO will require effective airground data link communication and negotiation protocols. This issue is especially critical in Arrival and Approach flight phase due to the variability of conditions into a short space-time environment where multiple aircraft simultaneously converge. Besides, several subtasks are closely related with effective air-ground negotiation protocols for 4D TBO in Terminal Areas: predicting accurate arrivals 4D trajectories, performing well established 4D trajectory formats for an effective interoperability between airborne and ground systems, designing efficient real-time aircraft arrival sequencer and scheduler algorithms, etc. In this paper we propose a 4D Trajectory Air- Ground Negotiation Protocol for Arrival and Approach Sequencing. The Negotiation Protocol has been implemented in an ad hoc multi-agent platform. Based on this proposal we summarize other relevant information that should be incorporated into the 4D trajectory information

Designing a Cockpit Functionalities Architecture for Trajectory Based Operations

Trajectory Based Operations (TBO) will require new procedures and systems to achieve a suitable automation of air traffic operations. Procedures and systems for automated operations are closely related and therefore frequently they need to be modeled in a combined way. Our group is currently employing recent agent-oriented methodological approaches to obtain conceptual models about TBO scenarios. Conceptual models define roles of air traffic entities as well as their interactions together with a detailed description of the entities’ architecture and dynamic behaviour. In this paper we present a cockpit functionality architecture built upon a methodological analysis and design of a TBO scenario as a multi-agent system. The proposed design has the advantage of mapping to an executable model for analytical simulation of TBO concepts and its modular architecture allows for a progressive integration of additional underlying models with specific functionalities

Exploring the ring-closing metathesis for the construction of the solomonamide macrocyclic core: identification of bioactive precursors

New synthetic strategies directed toward the novel cyclopeptides solomonamides have been explored utilizing an olefin metathesis as the key reaction. In the various strategies investigated, we worked on minimally oxidized systems, and the olefin metathesis reaction demonstrated efficiency and validity for the construction of the macrocyclic core. The described synthetic strategies toward the solomonamides are well suited for the subsequent access to the natural products and represent flexible and diversityoriented routes that allow for the generation of a variety of analogues via oxidative transformations. In addition, preliminary biological evaluations of the generated solomonamide precursors revealed antitumor activity against various tumor cell lines.This work was financially supported by the Ministerio de Economía y Competitividad (MINECO) (ref BIO2014-56092-R, CTQ2014-60223-R and CTQ2016-76311-R) and Junta de Andalucía and “Fondo Europeo de Desarrollo Regional-FEDER” (P12 CTS-1507). I.C.-S. thanks Ministerio de Educación, Cultura y Deporte for a predoctoral fellowship (FPU programme)

Experimentel ADS-B based surveillance

This paper describes an ADS-B implementation in air-to-air and ground based experimental surveillance within a prototype ATM system. The relations between airborne and ground systems related to surveillance are detailed, and the prototype surveillance systems and their algorithms described. Their performance is analysed, based both on simulated and real data

Mediterranean alcohol-drinking pattern and mortality in the SUN (Seguimiento Universidad de Navarra) Project: a prospective cohort study

Moderate alcohol intake has been related to lower mortality. However, alcohol use includes other dimensions beyond the amount of alcohol consumed. These aspects have not been sufficiently studied as a comprehensive entity. We aimed to test the relationship between an overall alcohol-drinking pattern and all-cause mortality. In a Mediterranean cohort study, we followed 18 394 Spanish participants up to 12 years. A validated 136-item FFQ was used to assess baseline alcohol intake. We developed a score assessing simultaneously seven aspects of alcohol consumption to capture the conformity to a traditional Mediterranean alcohol-drinking pattern (MADP). It positively scored moderate alcohol intake, alcohol intake spread out over the week, low spirit consumption, wine preference, red wine consumption, wine consumed during meals and avoidance of binge drinking. During the follow-up, 206 deaths were identified. For each 2-point increment in a 0-9 score of adherence to the MADP, we observed a 25% relative risk reduction in mortality (95% CI 11, 38%). Within each category of alcohol intake, a higher adherence to the MADP was associated with lower mortality. Abstainers (excluded from the calculations of the MADP) exhibited higher mortality (hazard ratio 1·82, 95% CI 1·14, 2·90) than participants highly adherent to the MADP. In conclusion, better adherence to an overall healthy alcohol-drinking pattern was associated with reduced mortality when compared with abstention or departure from this pattern. This reduction goes beyond the inverse association usually observed for moderate alcohol drinking. Even moderate drinkers can benefit from the advice to follow a traditional MADP

Optimisation of a Key Cross-Coupling Reaction Towards the Synthesis of a Promising Antileishmanial Compound

During the course of a research program aimed at identifying novel antileishmanial compounds, a multi-gram synthesis of N-(trans-4-((4-methoxy-3-((R)-3-methylmorpholino)-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)cyclohexyl)-2-methylpropane-1-sulfonamide ((R)-1) was required. This letter describes optimisation of the reaction conditions and protecting group strategy for a key Buchwald-Hartwig coupling, delivering the required quantities of (R)-1, as well as further compounds in the series