117 research outputs found
Development of a fast and flexible generic process for the reduction of nitro compounds
The hydrogenation of aromatic nitro substrates is a frequently used reaction in the multi-step fabrication of active pharmaceutical ingredients (APIs). Today most pharmaceutical production processes are performed in batch mode. In the frame of the C2-campaign speed is an important factor during the production of a multitude of possible API’s. A generic reactor set-up able to be adapted for the transformation of a specific substrate would reduce the development time and thereby the campaign time significantly. In the frame of the EU-project F3-Factory such a flexible and continuous reaction system for this important reaction class able to produce 1-5 kg API is being developed. To allow for an easy and fast adaptation of this process for a range of nitro substrates a substrates adoption methodology (SAM) is also being developed. A literature study of the nature of different reduction methods (H2 gas, H-Donor, CO gas, etc.) led to the conclusion that the liquid phase reduction of aromatic nitro substrates by either hydrogen gas or an H-donor is the most selective method. Following the requirements of that reaction type a flexible and modular reactor for the liquid phase reduction with a heterogeneous slurry catalyst was designed that can be adapted for reduction of a range of nitro compounds. The generic process provides the possibilities of swapping out a reactor or work up technology as required. The equipments of the generic process should be also able to operate at wider range of operational variables making it suitable for a range of substrates. The SAM identifies the necessary changes to a generic process and plant in order to adapt it for a given substrate. The objectives of this presentation is to highlight the design of a generic nitro reduction process and to demonstrate the application of this generic process on a pharmaceutical manufacturing case study involving the nitro reduction of 6-Nitroquinoline
Standing and travelling waves in a spherical brain model: the Nunez model revisited
The Nunez model for the generation of electroencephalogram (EEG) signals is naturally described as a neural field model on a sphere with space-dependent delays. For simplicity, dynamical realisations of this model either as a damped wave equation or an integro- differential equation, have typically been studied in idealised one dimensional or planar settings. Here we revisit the original Nunez model to specifically address the role of spherical topology on spatio-temporal pattern generation. We do this using a mixture of Turing instability analysis, symmetric bifurcation theory, center manifold reduction and direct simulations with a bespoke numerical scheme. In particular we examine standing and travelling wave solutions using normal form computation of primary and secondary bifurcations from a steady state. Interestingly, we observe spatio-temporal patterns which have counterparts seen in the EEG patterns of both epileptic and schizophrenic brain conditions
Do Credit Rating Agencies Add Value? Evidence from the Sovereign Rating Business Institutions
If rating agencies add no new information to markets, their actions are not a public policy concern. But as rating changes may be anticipated, testing whether ratings add value is not straightforward. This paper argues that ratings and spreads are both noisy signals of fundamentals and suggest ratings add value if, controlling for spreads, they help explain other variables. The paper additionally analyzes the different actions (ratings and outlooks) of the three leading agencies for sovereign debt, also considering the differing effects of more or less anticipated events. The results are consistent across a wide range of tests. Ratings do matter and hence how the market for ratings functions may be a public policy concern
The relative effects of upwelling and river flow on the phytoplankton diversity patterns in the ria of A Coruña (NW Spain)
Phytoplankton species assemblages in estuaries are connected to those in rivers and marine environments by local hydrodynamics leading to a continuous flow of taxa. This study revealed differential effects of upwelling and river flow on phytoplankton communities observed in 2011 along a salinity gradient from a river reservoir connected to the sea through a ria-marine bay system in A Coruña (NW Spain, 43° 16-21’ N, 8° 16-22’ W). With 130 phytoplankton taxa identified, the assemblages were dominated in general by diatoms, particularly abundant in the bay and in the estuary, but also by chlorophycea and cyanobacteria in the reservoir. Considering the entire seasonal cycle, the local assemblages were mainly characterized by changes in cryptophytes and diatoms, small dinoflagellates and some freshwater chlorophycea. Salinity, nitrate, and organic matter variables, were the main environmental factors related to the changes in the phytoplankton communities through the system, while phosphate and nitrite were also important for local communities in the estuary and the bay, respectively. The corresponding local phytoplankton assemblages showed moderate levels of connectivity. The estuarine community shared a variable number of taxa with the adjacent zones, depending on the relative strength of upwelling (major influence from the bay) and river flow (major influence of the reservoir) but had on average 35% of unique taxa. Consequently, local and zonal diversity patterns varied seasonally and were not simply related to the salinity gradient driven by the river flow.ANILE (CTM2009-08396 and CTM2010-08804-E), FIOME (CTM2011-28792-C02-01-MAR), and MEFIO (CTM2011-28792-C02-02-MAR) of the Plan Nacional de I+D+i (Spain), and RADIALES of the Instituto Español de Oceanografía (IEO, Spain).Versión del editor2,01
Structural studies of T4S systems by electron microscopy
Abstract: Type IV secretion (T4S) systems are large dynamic nanomachines that transport DNA and/or proteins through the membranes of bacteria. Analysis of T4S system architecture is an extremely challenging task taking into account their multi protein organisation and lack of overall global symmetry. Nonetheless the last decade demonstrated an amazing progress achieved by X-ray crystallography and cryo-electron microscopy. In this review we present a structural analysis of this dynamic complex based on recent advances in biochemical, biophysical and structural studies
Financing higher education in sub-Saharan Africa: some reflections and implications for sustainable development
The purpose of this article is to discuss how best to finance higher education in low-income countries of sub-Saharan Africa, drawing on benefits and drawbacks of the prevalent models of higher education finance, and lessons to be learned from countries which have seen greater expansion of their higher education systems in recent decades. Two main aspects are distinguished: first, a recognition of the powerful evidence that the general level of education in a country, its human capital, matters in determining a path to economic development; second, understanding that it does not help to produce large number of unemployed graduates whose only option due to absence of jobs is to engage in rent-seeking activities which in the end undermine both the essence of the human capital investment made, and job creation to be associated with human capital skills. Three areas are discussed, fully publicly financed “free” university education model; feasibility and lessons about fees; feasibility and lessons about loans. In addition, the paper makes suggestions on the measures to widen participation and promote equity and quality
Calendari científic escolar 2022 (català)
El proyecto “Calendario Científico Escolar 2022” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales.Proyecto FCT-20-16375 de la Fundación Española para la Ciencia y la Tecnología (FECYT); Agencia Estatal de Investigación (España); Ministerio de Ciencia e Innovación; Consejo Superior de Investigaciones Científicas; Universidad de León; Instituto de Ganadería de Montaña (IGM, CSIC-ULE); Cátedra de Cultura Científica de la Universidad del País Vasco/ Euskal Herriko Unibertsitatea (UPV/EHU); Delegación del CSIC en Castilla y León; Unidade de Divulgación Científica e Cultural - Universidade da Coruña; Academia de la Llingua Asturiana; Casa Árabe; Alliance Française de Gijón; University of California-Davis; Teagasc; CSIC-Representación Illes Balears; Balearic Islands Coastal Observing and Forecasting System (SOCIB); Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC, CSIC-UIB); Casa de la Ciència de Valencia (CSIC); Federación Española de Esperanto; Asociación Cultural Nogará Religada; Universidad de Zaragoza; Europa Laica; Museo Didáctico e Interactivo de Ciencias de la Vega Baja del Segura (MUDIC VBS-CV); Universidad Miguel Hernández; PuraVida SoftwareMujeres con Ciencia; Asociaţia Secular-Umanistă din România; Instituto Geológico y Minero de España (IGME); Centro de Biología Molecular Severo Ochoa (CSIC-UAM); Asociación Española para el Avance de la Ciencia (AEAC); Centro de Investigación del Cáncer (CIC, CSIC-USAL); Discapacitodos; Universitat de les Illes Balears (UIB); Escuela de Estudios Hispano-americanos (CSIC); PRISMA – Asociación para la diversidad afectivo-sexual y de género en ciencia, tecnología e innovación; Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC); Círculo Escéptico; Civiencia; Universidad Autónoma de Madrid; Escuela de Estudios Árabes (CSIC); Evento Ciencia.Peer reviewe
Calandario scientifico escolar 2022 (aragonés)
El proyecto “Calendario Científico Escolar 2022” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales.Proyecto FCT-20-16375 de la Fundación Española para la Ciencia y la Tecnología (FECYT); Agencia Estatal de Investigación (España); Ministerio de Ciencia e Innovación; Consejo Superior de Investigaciones Científicas; Universidad de León; Instituto de Ganadería de Montaña (IGM, CSIC-ULE); Cátedra de Cultura Científica de la Universidad del País Vasco/ Euskal Herriko Unibertsitatea (UPV/EHU); Delegación del CSIC en Castilla y León; Unidade de Divulgación Científica e Cultural - Universidade da Coruña; Academia de la Llingua Asturiana; Casa Árabe; Alliance Française de Gijón; University of California-Davis; Teagasc; CSIC-Representación Illes Balears; Balearic Islands Coastal Observing and Forecasting System (SOCIB); Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC, CSIC-UIB); Casa de la Ciència de Valencia (CSIC); Federación Española de Esperanto; Asociación Cultural Nogará Religada; Universidad de Zaragoza; Europa Laica; Museo Didáctico e Interactivo de Ciencias de la Vega Baja del Segura (MUDIC VBS-CV); Universidad Miguel Hernández; PuraVida Software.Mujeres con Ciencia; Asociaţia Secular-Umanistă din România; Instituto Geológico y Minero de España (IGME); Centro de Biología Molecular Severo Ochoa (CSIC-UAM); Asociación Española para el Avance de la Ciencia (AEAC); Centro de Investigación del Cáncer (CIC, CSIC-USAL); Discapacitodos; Universitat de les Illes Balears (UIB); Escuela de Estudios Hispano-americanos (CSIC); PRISMA – Asociación para la diversidad afectivo-sexual y de género en ciencia, tecnología e innovación; Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC); Círculo Escéptico; Civiencia; Universidad Autónoma de Madrid; Escuela de Estudios Árabes (CSIC); Evento Ciencia.Peer reviewe
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