5,654 research outputs found

    MODELING AND CONTROL OF AN AUTOREFRIGERATED CSTR POLYMERIZATION REACTOR: IMPACT OF THE NON-CONDENSABLE GASES

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    The concept of process intensification is applied to a CSTR polymerization reactor, where bulk reactions take place via styrene free-radicals, connected to a semi-flooded horizontal condenser; the aim is to operate the system in a safe and efficient way. The results obtained show that the developed model was able to reproduce the major dynamic characteristics, even with the presence of non-condensable gases. The existence of such gases prevents the reactor from ever reaching a steady-state, as they accumulate in the system, increasing the condenser pressure and the reactor temperature and reducing the contact area and the mass of liquid in the condenser. To overcome this problem, the control strategy of this work proposes a regular purge of the condenser gases in order to avoid a collapse of the system. In this context, different control algorithms were also analyzed and it was concluded that a fast and reliable control of the reactor is only possible when advanced controllers are used

    Origin of the bilateral structure of the supernova remnant G296.5+10

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    In this work, we have modelled the supernova remnant (SNR) G296.5+10, by means of 3D magnetohydrodynamics (MHD) simulations. This remnant belongs to the bilateral SNR group and has an additional striking feature: the rotation measure (RM) in its eastern and western parts are very different. In order to explain both the morphology observed in radio-continuum and the RM, we consider that the remnant expands into a medium shaped by the superposition of the magnetic field of the progenitor star with a constant Galactic magnetic field. We have also carried out a polarization study from our MHD results, obtaining synthetic maps of the linearly polarized intensity and the Stokes parameters. This study reveals that both the radio morphology and the reported RM for G296.5+10 can be explained if the quasi-parallel acceleration mechanism is taking place in the shock front of this remnant.Fil: Moranchel-Basurto, A.. Universidad Nacional Autónoma de México; MéxicoFil: Velazquez, P.. Universidad Nacional Autónoma de México; MéxicoFil: Giacani, Elsa Beatriz. Universidad de Buenos Aires. Facultad de Arquitectura y Urbanismo; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Toledo Roy, J. C.. Universidad Nacional Autónoma de México; MéxicoFil: Schneiter, E.. Universidad Nacional Autónoma de México; MéxicoFil: De Colle, F.. Universidad Nacional Autónoma de México; MéxicoFil: Esquivel, A.. Universidad Nacional Autónoma de México; Méxic

    Tumor Necrosis Factor-alpha Levels In Blood Cord Is Directly Correlated With The Body Weight Of Mothers

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    Obesity has emerged as major public health problem leading to increased morbidity and mortality. Epidemiological studies indicate that in many regions of the world, children and teenagers are increasingly affected by obesity, which contributes for a pessimistic projection for the near future. Maternal obesity has been implicated in metabolic disorders of the offspring, but there are no biological markers that can be detected early on life that predict the development of obesity in the offspring. Objective To evaluate the expression of inflammatory markers in the umbilical cord blood of babies of mothers with obesity/overweight, and correlate these markers with the body weight at age 9 months. Methods Anthropometric data of mothers and babies were obtained during prenatal evaluation, at birth and 9 months after birth. Cord blood was collected during delivery of 54 babies from mothers with obesity/overweight and of 50 babies from lean mothers. Tumour necrosis factor-alpha (TNF-alpha), transforming growth factor 1 beta, monocyte chemoattractant protein-1 and 2 (MCP-1/MCP-2) were determined in serum samples using enzyme-linked immunosorbent assay methods. Correlations were evaluated using the Spearman correlation coefficient, and comparisons were evaluated using the non-parametric Mann-Whitney U-test. Results Cord blood TNF-a was positively correlated with maternal body mass index. There was an inverse correlation between cord blood transforming growth factor 1 beta and baby body weight at birth. There was no biological marker that predicted body weight at age 9 months. Conclusion Although we have not found a biological marker to predict increased body weight at 9 months of age, the study shows that maternal obesity exposes the baby to higher TNF-a level in the early stages of life, and this can affect metabolic and inflammatory parameters during adulthood.2221021

    Delimitação e caracterização preliminar da Área de Proteção Ambiental do Camanducaia (SP/MG).

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    Este trabalho apresenta uma contribuição do geoprocessamento para a implantação da Área de Proteção Ambiental do Camanducaia (SP/MG). Através da combinação de técnicas de sensoriamento remoto, sistemas de informações geográficas e reconhecimentos em campo, foram produzidas informações georreferenciadas sobre a área e operacionalizada uma base cartográfica digital atualizada. Os resultados incluem a delimitação e descrição detalhada dos limites da APA e 10 mapas, na escala 1:250.000, sobre os principais componentes da paisagem da área

    Euclid: Superluminous supernovae in the Deep Survey

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    Context. In the last decade, astronomers have found a new type of supernova called superluminous supernovae (SLSNe) due to their high peak luminosity and long light-curves. These hydrogen-free explosions (SLSNe-I) can be seen to z ~ 4 and therefore, offer the possibility of probing the distant Universe. Aims. We aim to investigate the possibility of detecting SLSNe-I using ESA’s Euclid satellite, scheduled for launch in 2020. In particular, we study the Euclid Deep Survey (EDS) which will provide a unique combination of area, depth and cadence over the mission. Methods. We estimated the redshift distribution of Euclid SLSNe-I using the latest information on their rates and spectral energy distribution, as well as known Euclid instrument and survey parameters, including the cadence and depth of the EDS. To estimate the uncertainties, we calculated their distribution with two different set-ups, namely optimistic and pessimistic, adopting different star formation densities and rates. We also applied a standardization method to the peak magnitudes to create a simulated Hubble diagram to explore possible cosmological constraints. Results. We show that Euclid should detect approximately 140 high-quality SLSNe-I to z ~ 3.5 over the first five years of the mission (with an additional 70 if we lower our photometric classification criteria). This sample could revolutionize the study of SLSNe-I at z > 1 and open up their use as probes of star-formation rates, galaxy populations, the interstellar and intergalactic medium. In addition, a sample of such SLSNe-I could improve constraints on a time-dependent dark energy equation-of-state, namely w(a), when combined with local SLSNe-I and the expected SN Ia sample from the Dark Energy Survey. Conclusions. We show that Euclid will observe hundreds of SLSNe-I for free. These luminous transients will be in the Euclid data-stream and we should prepare now to identify them as they offer a new probe of the high-redshift Universe for both astrophysics and cosmology.Acknowledgements. We thank the internal EC referees (P. Nugent and J. Brichmann) as well as the many comments from our EC colleagues and friends. C.I. thanks Chris Frohmaier and Szymon Prajs for useful discussions about supernova rates. C.I. and R.C.N. thank Mark Cropper for helpful information about the V IS instrument. C.I. thanks the organisers and participants of the Munich Institute for Astro- and Particle Physics (MIAPP) workshop “Superluminous supernovae in the next decade” for stimulating discussions and the provided online material. The Euclid Consortium acknowledges the European Space Agency and the support of a number of agencies and institutes that have supported the development of Euclid. A detailed complete list is available on the Euclid web site (http://www.euclid-ec.org). In particular the Agenzia Spaziale Italiana, the Centre National dEtudes Spatiales, the Deutsches Zentrum für Luft- and Raumfahrt, the Danish Space Research Institute, the Fundação para a Ciênca e a Tecnologia, the Ministerio de Economia y Competitividad, the National Aeronautics and Space Administration, The Netherlandse Onderzoekschool Voor Astronomie, the Norvegian Space Center, the Romanian Space Agency, the State Secretariat for Education, Research and Innovation (SERI) at the Swiss Space Office (SSO), the United Kingdom Space Agency, and the University of Helsinki. R.C.N. acknowledges partial support from the UK Space Agency. D.S. acknowledges the Faculty of Technology of the University of Portsmouth for support during his PhD studies. C.I. and S.J.S. acknowledge funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement No. [291222]. C.I. and M.S. acknowledge support from EU/FP7-ERC grant No. [615929]. E.C. acknowledge financial contribution from the agreement ASI/INAF/I/023/12/0. The work by KJ and others at MPIA on NISP was supported by the Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) under grant 50QE1202. M.B. and S.C. acknowledge financial contribution from the agreement ASI/INAF I/023/12/1. R.T. acknowledges funding from the Spanish Ministerio de Economía y Competitividad under the grant ESP2015-69020-C2- 2-R. I.T. acknowledges support from Fundação para a Ciência e a Tecnologia (FCT) through the research grant UID/FIS/04434/2013 and IF/01518/2014. J.R. was supported by JPL, which is run under a contract for NASA by Caltech and by NASA ROSES grant 12-EUCLID12-0004

    On some differential-geometric aspects of the Torelli map

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    In this note we survey recent results on the extrinsic geometry of the Jacobian locus inside Ag\mathsf{A}_g. We describe the second fundamental form of the Torelli map as a multiplication map, recall the relation between totally geodesic subvarieties and Hodge loci and survey various results related to totally geodesic subvarieties and the Jacobian locus.Comment: To appear on Boll. UMI, special volume in memory of Paolo de Bartolomei
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