Canvis de residència en temps de COVID-19: una mica d'oxigen per al despoblament rural

Altres ajuts: "la Caixa" Social Research (SR21-00312) i Alan Turing Institute (1162533)Després de la irrupció de la pandèmia de COVID-19, diverses veus, sobretot des d'àmbits no acadèmics, van especular sobre un potencial èxode urbà cap a les àrees rurals. Malgrat això, aquesta hipòtesi no ha pogut ser corroborada fins ara a causa de la manca de dades amb el detall territorial adequat. En aquest Perspectives Demogràfiques es mostren els principals resultats d'una recerca del Centre d'Estudis Demogràfics i la Universitat Autònoma de Barcelona, que analitza les migracions internes entre les ciutats, els espais periurbans i les àrees rurals durant l'any 2020, i les compara amb els quatre anys que precedeixen la pandèmia. Per a l'anàlisi, s'utilitzen les microdades de l'Estadística de Variacions Residencials (EVR) de l'Institut Nacional d'Estadística (INE), que contenen tots els canvis de residència entre els 8.131 municipis espanyols. Els resultats de 2020 mostren alteracions remarcables, que es van plasmar principalment en un descens dels moviments cap a les ciutats i en un augment en les sortides des d'elles, especialment cap a municipis rurals. Aquests fluxos de persones van tenir un notable impacte demogràfic en les àrees rurals. Tanmateix, i malgrat els canvis observats, la major part de les migracions internes van ser majoritàriament entre ciutats, tal i com passava abans de la pandèmia, i tot apunta que es va tractar d'un fet conjuntural.After the outbreak of the COVID-19 pandemic, several commentators, especially from non-academic fields, speculated about a potential exodus from urban to rural areas. However, this hypothesis has not been confirmed due to a lack of data with information capturing changes of residence at local level. This issue of Perspectives Demogràfiques offers the main results of a study led by the Centre for Demographic Studies and the Autonomous University of Barcelona which analyses internal migration between cities, suburbs, and rural areas in 2020, compared to migration patterns during the four years preceding the pandemic. The analysis used microdata from the Residential Variation Statistics (EVR) of the Spanish Statistical Office (INE) which cover all changes of residence in the country's 8,131 municipalities. The results show significant changes in internal migration patterns during 2020. Inmigration to cities decreased, while out-migration increased, especially to rural areas. The latter flow had an important demographic impact on country villages. Despite these changes, internal migratory movements between and within urban areas dominated, as they did prior to the pandemic. At the same time, monthly data suggest that the changes are likely a temporary outcome.Tras la irrupción de la pandemia de COVID-19, diversas voces, sobre todo desde ámbitos no académicos, especularon acerca de un potencial éxodo urbano hacia las áreas rurales. Sin embargo, esta hipótesis no ha podido ser corroborada hasta ahora debido a la falta de datos con el detalle territorial adecuado. En este Perspectives Demogràfiques se muestran los principales resultados de una investigación liderada por el Centre d'Estudis Demogràfics y la Universidad Autónoma de Barcelona, analizando las migraciones internas entre las ciudades, los espacios periurbanos y las áreas rurales durante el año 2020, comparando con los cuatro años que preceden a la pandemia. Para el análisis, se utilizan los microdatos de la Estadística de Variaciones Residenciales (EVR) del Instituto Nacional de Estadística (INE), que contienen todos los cambios de residencia entre los 8.131 municipios españoles. Los resultados muestran alteraciones reseñables en 2020, que se plasmaron principalmente en un descenso de los movimientos hacia las ciudades y en un aumento en las salidas desde ellas, especialmente hacia municipios rurales. Estos flujos de personas tuvieron un notable impacto demográfico en las áreas rurales. No obstante, a pesar de los cambios observados, la mayor parte de las migraciones internas fueron mayoritariamente entre ciudades, al igual que antes de la pandemia, y todo apunta a que se trató de un hecho coyuntural

Understanding Patterns of Internal Migration During the COVID-19 Pandemic in Spain

Existing empirical work has analysed the impacts ofCOVID-19 on mortality, fertility and international migration. Less is known about the ways in which the COVID-19 pandemic has influenced the patterns of internal migration. Anecdotal reports of mass migration from large cities to less populated areas have emerged but lack of data has prevented empirically assessing this hypothesis. Drawing on geographically granular administrative population register data, we aim to analyse the extent of change in the patterns of internal migration across the urban hierarchy in Spain during 2020. Our results show a decline of 2.5% in the number of internal migration moves, particularly during the early stages of the pandemic, returning to pre-pandemic levels in late 2020. Results also reveal unusually large net migration losses in core cities and net migration gains in rural areas. Net migration losses in cities and gains in rural areas particularly accumulated following the easing of some non-pharmaceutical interventions. Yet, these net losses and gains trended to pre-pandemic levels in late 2020, and movements between cities, and between cities and suburbs, continued to dominate the internal migration system. Thus, while the COVID-19 pandemic exerted notable changes in the geographic balance of internal migration flows, these changes appear to have been temporary and did not significantly alter the existing structures of the national migration system.</p

A Holistic Solution to Icing by Acoustic Waves: De-Icing, Active Anti-Icing, Sensing with Piezoelectric Crystals, and Synergy with Thin Film Passive Anti-Icing Solutions

Icing has become a hot topic both in academia and in the industry given its implications in transport, wind turbines, photovoltaics, and telecommunications. Recently proposed de-icing solutions involving the propagation of acoustic waves (AWs) at suitable substrates may open the path for a sustainable alternative to standard de-icing or anti-icing procedures. Herein, the fundamental interactions are unraveled that contribute to the de-icing and/or hinder the icing on AW-activated substrates. The response toward icing of a reliable model system consisting of a piezoelectric plate activated by extended electrodes is characterized at a laboratory scale and in an icing wind tunnel under realistic conditions. Experiments show that surface modification with anti-icing functionalities provides a synergistic response when activated with AWs. A thoughtful analysis of the resonance frequency dependence on experimental variables such as temperature, ice formation, or wind velocity demonstrates the application of AW devices for real-time monitoring of icing processes

Photonic sensor systems for the identification of hydrocarbons and crude oils in static and flow conditions

Identification of hydrocarbons and crude oils is typically carried out with samples that, taken from natural sources or refineries, must be brought to the laboratory for their analysis with rather sophisticated instruments. Alternatively, “in situ” procedures have been also developed for this purpose. In this work, we propose the use of a series of several sensor systems based on photonic transducers in the form of chips for the identification and classification of crude oils and hydrocarbons through the determination of their refractive index in the visible and absorption in the near infrared regions of the electromagnetic spectrum. Two of the photonic transducers rely on modifications of a Bragg microcavity and they monitor the changes in visible light interference phenomena that occur in response to the variation of the refractive index of oils. The third one, in the form of a dielectric mirror, monitors the near infrared absorption of crude oils and hydrocarbons through the recording of a transflectance spectrum. The capacity of these transducers for crude oil identification is proved by the analysis of a series of oils and distilled fractions that have been properly identified and classified as a function of their density and partition of long hydrocarbon chains. The three photonic transducers are operated with optical fibers and can be used in static and dynamic modes, this latter under conditions that are especially well-suited for “insitu” analysis of oil streams in real facilities. The proved resistance of the chips to high pressure and temperature conditions supports their suitability to withstand harsh working environments as those existing in extraction wells.Peer reviewe

The Latest Mars Climate Database (MCD v5.1)

For many years, several teams around the world have developed GCMs (General Circulation Model or Global Climate Model) to simulate the environment on Mars. The GCM developed at the Laboratoire de Météorologie Dynamique in collaboration with several teams in Europe (LATMOS, France, University of Oxford, The Open University, the Instituto de Astrofisica de Andalucia), and with the support of ESA and CNES is currently used for many applications. Its outputs have also regularly been compiled to build a Mars Climate Database, a freely available tool useful for the scientific and engineering communities. The Mars Climate Database (MCD) has over the years been distributed to more than 150 teams around the world. Following the recent improvements in the GCM, a new series of reference simulations have been run and compiled into a new version (version5.1) of the Mars Climate Database, released in the first half of 2014. To summarize, MCD v5.1 provides: - Climatologies over a series of dust scenarios: standard year, cold (ie: low dust), warm (ie: dusty atmosphere) and dust storm, all topped by various cases of Extreme UV solar inputs (low, mean or maximum). These scenarios differ from those of previous versions of the MCD (version 4.x) as they have been derived from home-made, instrument-derived (TES, THEMIS, MCS, MERs), dust climatology of the last 8 Martian years. - Mean values and statistics of main meteorological variables (atmospheric temperature, density, pressure and winds), as well as surface pressure and temperature, CO2 ice cover, thermal and solar radiative fluxes, dust column opacity and mixing ratio, [H20] vapor and ice columns, concentrations of many species: [CO], [O2], [O], [N2], [H2], [O3], ... - A high resolution mode which combines high resolution (32 pixel/degree) MOLA topography records and Viking Lander 1 pressure records with raw lower resolution GCM results to yield, within the restriction of the procedure, high resolution values of atmospheric variables. - The possibility to reconstruct realistic conditions by combining the provided climatology with additional large scale and small scale perturbations schemes. At EGU, we will report on the latest improvements in the Mars Climate Database, with comparisons with available measurements from orbit (e.g.: TES, MCS) or landers (Viking, Phoenix, MSL)

Martian Atmospheric Aerosols Composition and Distribution Retrievals During the First Martian Year of NOMAD/TGO Solar Occultation Measurements: 2. Extended Results, End of MY 34 and First Half of MY 35

This is the second part of Stolzenbach et al. (2023, https://doi.org/10.1029/2022JE007276), named hereafter Paper I, extends the period to the end of MY 34 and the first half of MY 35. This encompasses the end phase of the MY 34 Global Dust Storm (GDS), the MY 34 C-Storm, the Aphelion Cloud Belt (ACB) season of MY 35, and an unusual early dust event of MY 35 from L$_S$ 30° to L$_S$ 55°. The end of MY 34 overall aerosol size distribution shows the same parameters for dust and water ice to what was seen during the MY 34 GDS. Interestingly, the layered water ice vertical structure of MY 34 GDS disappears. The MY 34 C-Storm maintains condition like the MY 34 GDS. A high latitude layer of bigger water ice particles, close to 1 μm, is seen from 50 to 60 km. This layered structure is linked to an enhanced meridional transport characteristic of high intensity dust event which put the MY 34 C-Storm as particularly intense compared to non-GDS years C-Storms as previously suggested by Holmes et al. (2021, https://doi.org/10.1016/j.epsl.2021.117109). Surprisingly, MY 35 began with an unusually large dust event (Kass et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AGUFMP039…01K) found in the Northern hemisphere during L$_S$ 35° to L$_S$ 50°. During this dust event, the altitude of aerosol first detection is roughly equal to 20 km. This is close to the values encountered during the MY 34 GDS, its decay phase and the C-Storm of the same year. Nonetheless, no vertical layered structure was observed

Martian Atmospheric Aerosols Composition and Distribution Retrievals During the First Martian Year of NOMAD/TGO Solar Occultation Measurements: 1. Methodology and Application to the MY 34 Global Dust Storm

Since the beginning of the Trace Gas Orbiter (TGO) science operations in April 2018, its instrument “Nadir and Occultation for MArs Discovery” (NOMAD) supplies detailed observations of the IR spectrums of the Martian atmosphere. We developed a procedure that allows us to evaluate the composition and distribution\u27s parameters of the atmospheric Martian aerosols. We use a retrieval program (RCP) in conjunction with a radiative forward model (KOPRA) to evaluate the vertical profile of aerosol extinction from NOMAD measurements. We then apply a model/data fitting strategy of the aerosol extinction. In this first article, we describe the method used to evaluate the parameters representing the Martian aerosol composition and size distribution. MY 34 GDS showed a peak intensity from L$_S$ 190° to 210°. During this period, the aerosol content rises multiple scale height, reaching altitudes up to 100 km. The lowermost altitude of aerosol\u27s detection during NOMAD observation rises up to 30 km. Dust aerosols r$_{eff}$ were observed to be close to 1 μm and its ν$_{eff}$ lower than 0.2. Water ice aerosols r$_{eff}$ were observed to be submicron with a ν$_{eff}$ lower than 0.2. The vertical aerosol structure can be divided in two parts. The lower layers are represented by higher r$_{eff}$ than the upper layers. The change between the lower and upper layers is very steep, taking only few kilometers. The decaying phase of the GDS, LS 210°–260°, shows a decrease in altitude of the aerosol content but no meaningful difference in the observed aerosol\u27s size distribution parameters

Metformin reduces macrophage HIF1α-dependent proinflammatory signaling to restore brown adipocyte function in vitro

© 2021 The Authors.Therapeutic potential of metformin in obese/diabetic patients has been associated to its ability to combat insulin resistance. However, it remains largely unknown the signaling pathways involved and whether some cell types are particularly relevant for its beneficial effects. M1-activation of macrophages by bacterial lipopolysaccharide (LPS) promotes a paracrine activation of hypoxia-inducible factor-1α (HIF1α) in brown adipocytes which reduces insulin signaling and glucose uptake, as well as β-adrenergic sensitivity. Addition of metformin to M1-polarized macrophages blunted these signs of brown adipocyte dysfunction. At the molecular level, metformin inhibits an inflammatory program executed by HIF1α in macrophages by inducing its degradation through the inhibition of mitochondrial complex I activity, thereby reducing oxygen consumption in a reactive oxygen species (ROS)-independent manner. In obese mice, metformin reduced inflammatory features in brown adipose tissue (BAT) such as macrophage infiltration, proinflammatory signaling and gene expression, and restored the response to cold exposure. In conclusion, the impact of metformin on macrophages by suppressing a HIF1α-dependent proinflammatory program is likely responsible for a secondary beneficial effect on insulin-mediated glucose uptake and β-adrenergic responses in brown adipocytes.This work was funded by grants RTI2018-094052-B-100 (MCIN/AEI/10.13039/501100011033/FEDER) , S2017/BMD-3684 (Comunidad de Madrid, Spain), Fundación Ramón Areces (Spain) and CIBERdem (ISCIII) to A.M.V., grant S2010/BMD-2423 (Comunidad de Madrid, Spain) to M.J.O. and A.M.V., PID2019-106371RB-I00 (MCIN/ AEI /10.13039/501100011033/ FEDER) to J.A and PI16/00789 (ISCIII, Spain) to M.A.F.-M. We also acknowledge all members of AMV's laboratory for helpful discussions. M.F. and B.V were supported by Inserm, CNRS, Université de Paris, and Région Ile-de-France. We also acknowledge the EFSD Albert Reynolds travel grant fellowship to V.F

Modeling the martian atmosphere with the LMD global climate model

Our Global Climate Model (GCM) of the Martian atmosphere is the result of twenty years of ongoing collaboration between our teams and has matured to the point of enabling to study the main cycles (dust, CO2, water) of present-day and past Martian climates. At the 2014 scientific assembly, we will report on the latest developments and improvements of our GCM, and also present the latest version of the Mars Climate Database (version 5.1) that is derived from GCM outputs, along with comparisons with available measurements (from TES, MCS, Viking, Phoenix, Curiosity, etc.)

Martian Atmospheric Aerosols Composition and Distribution Retrievals During the First Martian Year of NOMAD/TGO Solar Occultation Measurements: 2. Extended Results, End of MY 34 and First Half of MY 35

This is the second part of Stolzenbach et al. (2023, https://doi.org/10.1029/2022JE007276), named hereafter Paper I, extends the period to the end of MY 34 and the first half of MY 35. This encompasses the end phase of the MY 34 Global Dust Storm (GDS), the MY 34 C‐Storm, the Aphelion Cloud Belt (ACB) season of MY 35, and an unusual early dust event of MY 35 from LS 30° to LS 55°. The end of MY 34 overall aerosol size distribution shows the same parameters for dust and water ice to what was seen during the MY 34 GDS. Interestingly, the layered water ice vertical structure of MY 34 GDS disappears. The MY 34 C‐Storm maintains condition like the MY 34 GDS. A high latitude layer of bigger water ice particles, close to 1 μm, is seen from 50 to 60 km. This layered structure is linked to an enhanced meridional transport characteristic of high intensity dust event which put the MY 34 C‐Storm as particularly intense compared to non‐GDS years C‐Storms as previously suggested by Holmes et al. (2021, https://doi.org/10.1016/j.epsl.2021.117109). Surprisingly, MY 35 began with an unusually large dust event (Kass et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AGUFMP039…01K) found in the Northern hemisphere during LS 35° to LS 50°. During this dust event, the altitude of aerosol first detection is roughly equal to 20 km. This is close to the values encountered during the MY 34 GDS, its decay phase and the C‐Storm of the same year. Nonetheless, no vertical layered structure was observed