Influencia de la restricción de vitamina A en la dieta de cerdos ibéricos sobre el metabolismo y la transcripción de genes relacionados con lipogénesis

Vitamin A is a liposoluble vitamin obtained from the diet with multiple physiological actions in all animal tissues, including an antiadipogenic action which seems to be limited to muscular tissues. Thus, vitamin A restriction has been proposed as a strategy for improving meat and carcass quality in farm animals. In this work we have studied the effects of vitamin A dietary restriction on productive traits, tissue fatty acid composition and expression of a panel of adipogenic and lipogenic candidate genes in Iberian pigs. Forty Torbiscal pigs were fed with a standard or a Vitamin A restricted diet from two months of age till their sacrifice conducted in two batches, at 100 and 160 Kg live weight. Diet had no significant effect on growth, fatness, yields or intramuscular fat, but animals receiving no vitamin A supplementation showed higher monounsaturated fatty acids and lower saturated fatty acids in back fat and loin samples than the control ones. Adipose tissue SCD gene expression was higher in vitamin A restricted animals, as occurs with CRABP II expression. On the other hand, RXRG expression was higher in control group, in agreement with the influence on transcription of retinoic acid and its potential relationship with adipogenesis and lipogenesis.La vitamina A es una vitamina liposoluble obtenida de la dieta con numerosas funciones fisiológicas en los tejidos animales, incluyendo un efecto antiadipogénico aparentemente limitado al tejido muscular. La restricción de vitamina A se ha propuesto como una herramienta para mejorar la calidad de la canal y de la carne en animales de abasto. En el presente trabajo hemos estudiado el efecto de la restricción de vitamina A en el pienso sobre caracteres productivos, composición tisular de ácidos grasos y expresión de un panel de genes candidato con funciones adipogénicas y lipogénicas en cerdos ibéricos. Cuarenta cerdos de la estirpe Torbiscal fueron alimentados con pienso estándar o con pienso sin vitamina A en el corrector desde los dos meses de edad hasta su sacrificio, realizado en dos lotes (a 100 y 160 kg de peso vivo). La dieta no afectó al crecimiento, engrasamiento, rendimientos ni a la cantidad de grasa intramuscular, pero los animales restringidos mostraron una cantidad mayor de ácidos grasos monoinsaturados y menor de saturados en el tocino dorsal y en el lomo. El análisis de expresión génica en el tocino dorsal mostró una mayor expresión de SCD y CRABP II en el grupo restringido. Por otro lado, la expresión de RXRG fue mayor en el grupo control, en concordancia con el efecto modulador de la transcripción génica del ácido retinoico y su potencial relación con la adipogénesis y lipogénesis

Estudios sobre consumos culturales en la Argentina contemporánea

Este libro es el resultado del trabajo de un equipo de investigadores e investigadoras de diferentes universidades del país que fueron seleccionados/os a través de un concurso nacional con el fin de participar en un proyecto centrado en el análisis de la producción reciente de las ciencias sociales, en el marco del Programa de Investigación sobre la Sociedad Argentina Contemporánea (PISAC). En efecto, el PISAC asumió la tarea de revisar integralmente la producción escrita de las ciencias sociales en relación con la sociedad argentina contemporánea, teniendo en cuenta la diversidad de enfoques y perspectivas, así como la heterogeneidad regional e institucional de los ámbitos de producción. El objetivo de tal revisión crítica permitiría, en última instancia, construir estados de la cuestión exhaustivos sobre distintos núcleos temáticos referidos a aspectos sociales, políticos, económicos y culturales de la Argentina actual. Cabe señalar que este proyecto se funda en la rica tradición de investigación social de nuestro país, aunque también reconoce su carácter fragmentado, las asimetrías regionales e institucionales, la tendencia a la metropolitanización en la definición de objetos de indagación y en la construcción de interpretaciones científicas, las dificultades para la circulación de los conocimientos y la relativa invisibilización de gran parte de la producción, en particular la que se realiza en ámbitos periféricos

Low-ionization pairs of knots in planetary nebulae: physical properties and excitation

We obtained optical long-slit spectra of four planetary nebulae (PNe) with low-ionization pair of knots, namely He 1-1, IC 2149, KjPn 8 and NGC 7662. These data allow us to derive the physical parameters and excitation of the pairs of knots, and those of higher ionization inner components of the nebulae, separately. Our results are as follows. 1) The electron temperatures of the knots are within the range 9500 to 14500 K, similar to the temperatures of the higher ionization rims/shells. 2) Typical knots' densities are 500 to 2000 cm^{-3}. 3) Empirical densities of the inner rims/shells are higher than those of the pairs of knots, by up to a factor of 10. Theoretical predictions, at variance with the empirical results, suggest that knots should be denser than the inner regions, by at least a factor of 10. 4) Empirical and theoretical density contrasts can be reconciled if we assume that at least 90% of the knots' gas is neutral (likely composed of dust and molecules). 5) By using Raga et al. (2008) shock modeling and diagnostic diagrams appropriated for spatially resolved PNe, we suggest that high-velocity shocked knots traveling in the photoionized outer regions of PNe can explain the emission of the pairs of knots analysed in this paper.Comment: The paper contains 11 pages (6 figures and 5 tables). Accepted for publication in MNRAS; added last paragraph for subsection 7.

Structural and electrical study of the topological insulator SnBi2Te4 at high pressures

We report high-pressure X-ray diffraction and electrical measurements of the topological insulator SnBi2Te4 at room temperature. The pressure dependence of the structural properties of the most stable phase of SnBi2Te4 at ambient conditions (trigonal phase) have been experimentally determined and compared with results of our ab initio calculations. Furthermore, a comparison of SnBi2Te4 with the parent compound Bi2Te3 shows that the central TeSnTe trilayer, which substitutes the Te layer at the center of the TeBiTeBiTe layers of Bi2Te3, plays a minor role in the compression of SnBi2Te4. Similar to Bi2Te3, our resistance measurements and electronic band structure simulations in SnBi2Te4 at high pressure suggest that this compound exhibits a pressure-induced electronic topological transition or Lifshitz transition between 3.5 and 5.0 GPa. (C) 2016 Published by Elsevier B.V.We thank Dr. Philipp Urban for preparing the sample. This work has been performed under financial support from Spanish MINECO under projects MAT2013-46649-C4-2-P, MAT2015-71070-REDC and CTQ2015-67755-C2-1-R and from Spanish Ministerio de Educacion, Cultura y Deporte as part of "Programa Campus de Excelencia Internacional/Programa de Valoracion y Recursos Conjuntos de I + D + i VLC/CAMPUS" through projects SP20140701 and SP20140871. One of the experiments were performed at MSPD-BL04 beamline at ALBA Synchrotron with the collaboration of ALBA staff. J.A.S. thanks "Juan de la Cierva" fellowship program for funding. A. A.-C. and J.S.-B. are also grateful to Spanish MINECO for the FPI (BES-2013-066112) and Ramon y Cajal (RyC-2010-06276) fellowships. We acknowledge Diamond Light Source for time on beamline I15 under Proposal EE9102.Vilaplana Cerda, RI.; Sans Tresserras, JÁ.; Manjón Herrera, FJ.; Andrada-Chacón, A.; Sánchez-Benitez, J.; Popescu, C.; Gomis, O.... (2016). Structural and electrical study of the topological insulator SnBi2Te4 at high pressures. Journal of Alloys and Compounds. 685:962-970. https://doi.org/10.1016/j.jallcom.2016.06.170S96297068

Blazar spectral variability as explained by a twisted inhomogeneous jet

Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming1. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles2, with possible intervention of shock waves3,4 or turbulence5. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events6,7,8,9,10 and can also explain specific properties of blazar emission, such as intra-day variability11, quasi-periodicity12,13 and the delay of radio flux variations relative to optical changes14. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions—such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution—can explain snapshots of the spectral behaviour of blazars in many cases15,16. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities17 or rotation of the twisted jet6 cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016–2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing angle. The agreement between observations and theoretical predictions can be seen as further validation of the relativistic beaming theory

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Blazar spectral variability as explained by a twisted inhomogeneous jet

© 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles, with possible intervention of shock waves or turbulence. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events and can also explain specific properties of blazar emission, such as intra-day variability, quasi-periodicity and the delay of radio flux variations relative to optical changes. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions - such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution - can explain snapshots of the spectral behaviour of blazars in many cases. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities or rotation of the twisted jet cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016-2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing angle. The agreement between observations and theoretical predictions can be seen as further validation of the relativistic beaming theory

Investigating the multiwavelength behaviour of the flat spectrum radio quasar CTA 102 during 2013-2017

We present a multiwavelength study of the flat-spectrum radio quasar CTA 102 during 2013-2017. We use radio-to-optical data obtained by the Whole Earth Blazar Telescope, 15 GHz data from the Owens Valley Radio Observatory, 91 and 103 GHz data from the Atacama Large Millimeter Array, near-infrared data from the Rapid Eye Monitor telescope, as well as data from the Swift (optical-UV and X-rays) and Fermi (gamma-rays) satellites to study flux and spectral variability and the correlation between flux changes at different wavelengths. Unprecedented gamma-ray flaring activity was observed during 2016 November-2017 February, with four major outbursts. A peak flux of (2158 +/- 63) x 10(-8) ph cm(-2) s(-1), corresponding to a luminosity of (2.2 +/- 0.1) x10(50) erg s(-1), was reached on 2016 December 28. These four gamma-ray outbursts have corresponding events in the near-infrared, optical, and UV bands, with the peaks observed at the same time. A general agreement between X-ray and gamma-ray activity is found. The gamma-ray flux variations show a general, strong correlation with the optical ones with no time lag between the two bands and a comparable variability amplitude. This gamma-ray/optical relationship is in agreement with the geometrical model that has successfully explained the low-energy flux and spectral behaviour, suggesting that the long-term flux variations are mainly due to changes in the Doppler factor produced by variations of the viewing angle of the emitting regions. The difference in behaviour between radio and higher energy emission would be ascribed to different viewing angles of the jet regions producing their emission

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries