Mexico City: industrialization, migration and the labour force, 1930-1970
In: Selected studies on the dynamics, patterns, and consequences of migration 1
In: Reports and papers in the social sciences 46
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In: Selected studies on the dynamics, patterns, and consequences of migration 1
In: Reports and papers in the social sciences 46
In: Common market law review, Band 36, Heft 4, S. 831-840
ISSN: 0165-0750
In: Estudios Fronterizos, Heft 17, S. 11-35
ISSN: 2395-9134
Este trabajo intenta plantear y enfocar los distintos fenómenos migratorios que ocurren en la frontera sur de México. Como punto de partida, presenta algunas de las ideas que han proliferado en torno a las migraciones hacia la frontera sur de México, muchas de las cuales son comunes a las de otros contextos fronterizos. Como parte de un proyecto de investigación desarrollado se hace uso de las indagaciones de campo realizadas en la región del Soconusco, en el Estado de Chiapas. En base a los resultados debe enfatizarse que la carencia de conocimientos requiere de estudios más profundos y diversos enfocados al análisis de otros flujos migratorios y se puede concluir que la forma adecuada de enfrentar este fenómeno no radica en las medidas de control, sino más bien en la oportuna contribución para solucionar los problemas de origen.
In: Journal of consumer protection and food safety: Journal für Verbraucherschutz und Lebensmittelsicherheit : JVL, Band 1, Heft 3, S. 187-196
ISSN: 1661-5867
La cobertura de este estudio dentro del proyecto de investigación PGC2018-099174-B-I00 (Ministerio de Ciencia e Innovación) del Gobierno de España/Fondos FEDER.
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The Large Magellanic Cloud (LMC) is the closest and most studied example of an irregular galaxy. Among its principal defining morphological features, its off-centred bar and single spiral arm stand out, defining a whole family of galaxies known as the Magellanic spirals (Sm). These structures are thought to be triggered by tidal interactions and possibly maintained via gas accretion. However, it is still unknown whether they are long-lived stable structures. In this work, by combining photometry that reaches down to the oldest main sequence turn-off in the colour-magnitude diagrams (CMD, up to a distance of ∼4.4 kpc from the LMC centre) from the SMASH survey and CMD fitting techniques, we find compelling evidence supporting the long-term stability of the LMC spiral arm, dating the origin of this structure to more than 2 Gyr ago. The evidence suggests that the close encounter between the LMC and the Small Magellanic Cloud (SMC) that produced the gaseous Magellanic Stream and its Leading Arm also triggered the formation of the LMC's spiral arm. Given the mass difference between the Clouds and the notable consequences of this interaction, we can speculate that this should have been one of their closest encounters. These results set important constraints on the timing of LMC-SMC collisions, as well as on the physics behind star formation induced by tidal encounters. © ESO 2020. ; TRL, CG, MM, FS and LM acknowledge financial support through grants (AEI/FEDER, UE) AYA201789076-P, AYA2016-77237-C3-1-P (RAVET project) and AYA2015-63810-P, as well as by Ministerio de Ciencia, Innovacion y Universidades (MCIU), through Juan de la Cierva - Formacion grant (FJCI-2016-30342) and the State Budget and by Consejeria de Economia, Industria, Comercio y Conocimiento of the Canary Islands Autonomous Community, through Regional Budget. TRL also acknowledges support from the Spanish Public State Employment Service (SEPE). Y.C. acknowledges support from NSF grant AST 1655677. SC acknowledges support from Premiale INAF "MITIC" and grant AYA201342781P from the Ministry of Economy and Competitiveness of Spain, he has also been supported by INFN (Iniziativa specifica TAsP). M-RC acknowledges support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 682115). SRM acknowledges support through NSF grant AST-1909497. DMD acknowledges support through grant AYA2016-81065-C2-2 and through the "Centre of Excellence Severo Ochoa" award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709) and from grant PGC2018-095049-B-C21. AM acknowledges financial support from FONDECYT Regular 1181797 and funding from the Max Planck Society through a Partner Group grant. R.R.M. acknowledges partial support from project BASAL AFB-170002 as well as FONDECYT project Nffi1170364. This research makes use of python (http://www.python.org); Matplotlib (Hunter 2007) and Astropy (Astropy Collaboration 2013, 2018). Based on observations at Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory (NOAO Prop. ID: 2013A-0411 and 2013B0440; PI: Nidever), which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. This project used data obtained with the Dark Energy Camera (DECam), which was constructed by the Dark Energy Survey (DES) collaboration. Funding providers for the DES Projects can be found in https://www.darkenergysurvey.org/collaboration-and-sponsors/ ; Peer reviewed
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We report the detection of three RR Lyrae (RRL) stars (two RRc and one RRab) in the ultra-faint dwarf (UFD) galaxy Centaurus I (Cen I) and two Milky Way (MW) δ Scuti/SX Phoenicis stars based on multi-epoch giz DECam observations. The two RRc stars are located within two times the half-light radius (rh) of Cen I, while the RRab star (CenI-V3) is at ∼6 rh. The presence of three distant RRL stars clustered this tightly in space represents a 4.7σ excess relative to the smooth distribution of RRL in the Galactic halo. Using the newly detected RRL stars, we obtain a distance modulus to Cen I of μ0 = 20.354 ± 0.002 mag (σ = 0.03 mag), a heliocentric distance of De = 117.7 ± 0.1 kpc (σ = 1.6 kpc), with systematic errors of 0.07 mag and 4 kpc. The location of the Cen I RRL stars in the Bailey diagram is in agreement with other UFD galaxies (mainly Oosterhoff II). Finally, we study the relative rate of RRc+RRd (RRcd) stars (fcd) in UFD and classical dwarf galaxies. The full sample of MW dwarf galaxies gives a mean of fcd = 0.28. While several UFD galaxies, such as Cen I, present higher RRcd ratios, if we combine the RRL populations of all UFD galaxies, the RRcd ratio is similar to the one obtained for the classical dwarfs (fcd ∼ 0.3). Therefore, there is no evidence for a different fraction of RRcd stars in UFD and classical dwarf galaxies. ; Fermilab LDRD project L2019-011 NASA Fermi Guest Investigator Program Cycle 9 91201 United States Department of Energy (DOE) National Science Foundation (NSF) Spanish Government UK Research & Innovation (UKRI) Science & Technology Facilities Council (STFC) UK Research & Innovation (UKRI) Higher Education Funding Council for England (HEFCE) National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign University of Chicago Ohio State University Mitchell Institute for Fundamental Physics and Astronomy at Texas AM University Financiadora de Inovacao e Pesquisa (Finep) Fundaco Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) Spanish Government German Research Foundation (DFG) Dark Energy Survey United States Department of Energy (DOE) University of California at Santa Cruz University of Cambridge, Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas-Madrid University of Chicago, University College London DES-Brazil Consortium University of Edinburgh ETH Zurich United States Department of Energy (DOE) University of Chicago University of Illinois at Urbana-Champaign Institut de Ciencies de l'Espai (IEEC/CSIC) Institut de Fisica d'Altes Energies, Lawrence Berkeley National Laboratory Ludwig-Maximilians Universitat Munchen associated Excellence Cluster Universe University of Michigan, NSF's NOIRLab University of Nottingham Ohio State University OzDES Membership Consortium University of Pennsylvania University of Portsmouth Stanford University United States Department of Energy (DOE) Stanford University University of Sussex Texas AM University United States Department of Energy (DOE) DE-AC02-07CH11359 ; Versión publicada - versión final del editor
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This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1714977115/-/DCSupplemental. ; Knowledge about the biogeographic affinities of the world's tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world's tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests. ; European Union's Horizon 2020 Research and Innovation Programme under Marie Skłodowska-Curie Grant Agreement 660020, Instituto Bem Ambiental (IBAM), Myr Projetos Sustentáveis, IEF, and CNPq, CAPES FAPEMIG, German Research Foundation (DFG; Grants CRC 552, CU127/3-1, HO 3296/2-2, HO3296/4-1, and RU 816), UNAM-PAPIIT IN218416 and Semarnat-CONACYT 128136, Conselho Nacional de Desenvolvimento Científico e Tecnoloógico (CNPq, Brazil), Fundação Grupo Boticário de Proteção à Natureza/Brazil, PAPIIT-DGAPA-UNAM (Project IN-204215), National Geographic Society, National Foundation for Scientific and Technology Development Vietnam (Grant 106.11-2010.68), Operation Wallacea, and core funding for Crown Research Institutes from the New Zealand Ministry of Business, Innovation and Employment's Science and Innovation Group. ; Peer-reviewed ; Publisher Version
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