40 research outputs found

    La migración internacional en Costa Rica: estado actual y consecuencias

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    En la actualidad los flujos migratorios internacionales obedecen a las desigualdades existentes en los procesos de desarrollo económico y social de los países, a los efectos de políticas para atender dichos procesos, a conflictos sociopolíticos y situaciones de emergencia, todo lo cual afecta la sobrevivencia de las poblaciones más vulnerables. La estimación de la migración internacional es una necesidad cada vez más prioritaria a escala mundial y en la región latinoamericana en particular, dadas las características del contexto de globalización y desregulación de mercados imperante, con la consecuente mayor movilidad de recursos y población entre países. La agudización de la movilidad internacional de población hacia Costa Rica en la década del noventa y la ausencia de un censo nacional desde 1984, despertaron gran interés por el estudio de este fenómeno que tiene presencia histórica en el país, y generaron expectativas mayores sobre los resultados que arrojaría el Censo Nacional 2000. De las variables demográficas que determinan el crecimiento de la población, la migración internacional es la que presenta mayor dificultad para su captación y estimación, ya que una persona puede experimentar un número casi indeterminado de movimientos y cada movimiento involucrar al menos dos lugares o zonas (origen y destino). La definición tradicional de migración, utilizada y recomendada por Naciones Unidas, establece que la migración internacional es el cambio de país de la residencia habitual. De manera que un migrante internacional será aquella persona que en un determinado momento se encuentra residiendo en un país distinto al de nacimiento o al de residencia anterior (CELADE e IUSSP, 1985). Lo anterior implica una primera limitación, toda vez que esta definición operacional capta sólo movimientos o cambios permanentes de residencia, mientras que lo que parece estar predominando en el ámbito nacional y en la región latinoamericana, es una alta movilidad de la población. La movilidad espacial alude a un fenómeno más complejo, que involucra distintas modalidades de desplazamientos poblacionales, respondiendo a una multidimensionalidad de causas y afectando a un espacio de vida más amplio que sólo un origen y un destino. Entre las modalidades de movilidad, resaltan aquellos traslados de un país a otro por motivos estacionales o temporales –para realizar algún tipo de trabajo– así como los originados por turismo y estudio; lo cual provoca otras variantes de migración internacional como las poblaciones en tránsito, la residencia múltiple, el pluriempleo (traslados circulares o pendulares) y las migraciones de retorno. Esto establece retos a la definición y operacionalización de la migración internacional y, sobre todo, a las fuentes de información para su estudio: registros de entradas y salidas, censos y encuestas (Barquero,2000)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Centro Centroamericano de Población (CCP

    AL-FEC for streaming services in LTE E-MBMS

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    3rd Generation Partnership Project specified Application Layer - Forward Error Correction (AL-FEC) to be used for Enhanced Multimedia Broadcast Multicast Services (E-MBMS) in Long Term Evolution (LTE) networks. Specifically, Raptor coding is applied to both streaming and file delivery services. This article focuses on streaming services and investigates the optimum configuration of the AL-FEC mechanism depending on the signal-to-interference plus noise power ratio conditions. These configurations are compared with a scenario without an application layer protection to obtain the potential gain that can be achieved by means of AL-FEC. This article also studies the multiplexing of services within the AL-FEC time interleaving. These analyses were performed using a proprietary system level simulator and assuming both pedestrian and vehicular users. Different quality criterions were used to ensure the completeness of the study. Results show the significant benefit of using AL-FEC in E-MBMS in terms of coverage and service quality.This study was supported by the Spanish Ministry of Science under the project TEC2011-27723-C02-02.Calabuig Gaspar, J.; Monserrat Del Río, JF.; Gozálvez Serrano, D.; Gómez Barquero, D. (2013). AL-FEC for streaming services in LTE E-MBMS. EURASIP Journal on Wireless Communications and Networking. 2013(73):1-12. https://doi.org/10.1186/1687-1499-2013-73S1122013733GPP TS 25.346 V6.4.0, Introduction of the Multimedia Broadcast Multicast Service (MBMS) in the Radio Access Network (RAN); Stage 2, 2005.Deng H, Tao X, Lu J: Qos-aware resource allocation for mixed multicast and unicast traffic in OFDMA networks. EURASIP Journal on Wireless Communications and Networking 2012, 2012(195):1-10. 10.1186/1687-1499-2012-1953GPP TS 26.346 V9.5.0, Multimedia Broadcast/Multicast Service (MBMS); Protocols and codecs, 2011.Shokrollahi A: Raptor codes. IEEE Transactions on Information Theory 2006, 52(6):2251-2567. 10.1109/TIT.2006.8743903GPP TS 25.346 V7.5.0, Introduction of the Multimedia Broadcast/Multicast Service (MBMS) in the Radio Access Network (RAN); Stage 2, 2007.Martín-Sacristán D, Monserrat JF, Cabrejas J, Calabuig D, Garrigas S, Cardona N: On the way towards fourth-generation mobile: 3GPP LTE and LTE-advanced. EURASIP Journal on Wireless Communications and Networking 2009, 1-10. 10.1155/2009/3540893GPP TS 36.211 V.8.5.0, Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation, 2008.3GPP TS 36.300 V9.1.0, Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description, 2009.Monserrat JF, Calabuig J, Fernandez-Aguilella A, Gomez-Barquero D: Joint delivery of unicast and E-MBMS services in LTE networks. IEEE Transactions on Broadcasting. 2012, 58(2):157-167. 10.1109/TBC.2012.2191030Alexiou A, Bouras C, Kokkinos V, Papazois A, Tsichritzis G: Wireless Multi-Access Environments and Quality of Service Provisioning: Solutions and Application, Multimedia broadcasting in LTE networks. Edited by: Muntean GM, Trestian R. Hershey, PA: IGI Global; 2012:269-289.Wang N, Zhang Z: The impact of application layer Raptor FEC on the coverage of MBMS. Radio and Wireless Symposium, 2008 IEEE 2008, 223-226. 10.1109/RWS.2008.4463469Gomez-Barquero D, Fernandez-Aguilella A, Cardona N: Multicast delivery of file download services in evolved 3G mobile networks with HSDPA and MBMS. IEEE Transactions on Broadcasting. 2009, 55(4):742-751. 10.1109/TBC.2009.2032800Stockhammer T, Shokrollahi A, Watson M, Luby M, Gasiba T: Handbook of Mobile Broadcasting: DVB-H, DMB, ISDB-T and Media FLO, Application layer forward error correction for mobile multimedia broadcasting. Edited by: Furhet B, Ahson S. Boca Raton, FL: CRC Press; 2008:239–-280.Afzal J, Stockhammer T, Gasiba T, Xu W: Video streaming over MBMS: a system design approach. Journal of Multimedia. 2006, 1(5):25-35.Alexiou A, Bouras C, Kokkinos V, Papazois A, Tseliou G: Cellular Networks - Positioning, Performance Analysis, Reliability, Forward error correction for reliable e-MBMS transmissions in LTE networks. Edited by: Melikov A. Rijeka, Croatia: InTech; 2011:353-374.Munaretto D, Jurca D, Widmer J: Broadcast video streaming in cellular networks: An adaptation framework for channel, video and AL-FEC rates allocation. Wireless Internet Conference (WICON), 2010 The 5th Annual ICST 2010, 1-9.Bouras C, Kanakis N, Kokkinos V, Papazois A: Application layer forward error correction for multicast streaming over LTE networks. Int. J. Commun. Syst 2012. 10.1002/dac.2321RaptorQ technical overview, Qualcomm Technical Report 2010. http://www.qualcomm.com/instella_api/asset/3cd5b620-afea-012d-72bc-12313804dc61Mladenov T, Kim K, Nooshabadi S: Forward error correction with RaptorQ Code on embedded systems. Circuits and Systems (MWSCAS), 2011 IEEE 54th International Midwest Symposium 2011, 1-4. 10.1109/MWSCAS.2011.6026424Calabuig J, Monserrat JF, Martín-Sacristán D, Olmos J: Comparison of multicast/broadcast services in Long Term Evolution Advanced and IEEE 802.16m networks. Wirel. Commun. Mob. Comput. 2012. 10.1002/wcm.2229Jiang X, Zhu G, Wu W, Gao Y: Design of LTE E-MBMS Dynamic Scheduling Information. Wireless Communications Networking and Mobile Computing (WiCOM), 2010 6th International Conference on 2010, 1-5. 10.1109/WICOM.2010.56002103GPP TS 36.331 V.9.9.0, Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol Specification, 2011.Alberi Morel M-L, Kerboeuf S, Sayadi B, Leprovost Y, Faucheux F: Performance Evaluation of Channel Change for DVB-SH Streaming Services. Communications (ICC), 2010 IEEE International Conference on 2010, 1-6. 10.1109/ICC.2010.5502523WINNER + IMT-Advanced Calibration: Guidelines, software and results. 2009. http://projects.celtic-initiative.org/winner+/WINNER+%20Evaluation%20Group.htmlBrueninghaus K, Astely D, Salzer T, Visuri S, Alexiou A, Karger S, Seraji GA: Link performance models for system level simulations of broadband radio access systems, in Proceedings of 16th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC). Berlin, Germany 2005, 4: 2306-2311. 10.1109/PIMRC.2005.1651855ITU-R M.2135, Guidelines for evaluation of radio interface technologies for IMT-Advanced. 2008. http://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-M.2135-2008-PDF-E.pdf3GPP TS 36.101 V.9.10.0, Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception. 2011.Rong L, Ben Haddada O, Elayoubi S-E: Analytical Analysis of the Coverage of a MBSFN OFDMA Network," Global Telecommunications Conference . IEEE GLOBECOM 2008. IEEE 2008, 1-5. 10.1109/GLOCOM.2008.ECP.4593GPP TSG-SA WG4 S4-100861, Relation between MBSFN area and intended MBMS service reception area, 2010.3GPP TR 36.213 V.9.3.0, Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures, 2010

    Differences in Adipose Tissue and Lean Mass Distribution in Patients with Collagen VI Related Myopathies Are Associated with Disease Severity and Physical Ability

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    Mutations in human collagen VI genes cause a spectrum of musculoskeletal conditions in children and adults collectively termed collagen VI-related myopathies (COL6-RM) characterized by a varying degree of muscle weakness and joint contractures and which include Ullrich Congenital Muscular Dystrophy (UCMD) and Bethlem Myopathy (BM). Given that collagen VI is one of the most abundant extracellular matrix proteins in adipose tissue and its emerging role in energy metabolism we hypothesized that collagen VI deficiency might be associated with alterations in adipose tissue distribution and adipokines serum profile. We analyzed body composition by means of dual-energy X-ray absorptiometry in 30 pediatric and adult COL6-RM myopathy patients representing a range of severities (UCMD, intermediate-COL6-RM, and BM). We found a distinctive pattern of regional adipose tissue accumulation which was more evident in children at the most severe end of the spectrum. In particular, the accumulation of fat in the android region was a distinguishing feature of UCMD patients. In parallel, there was a decrease in lean mass compatible with a state of sarcopenia, particularly in ambulant children with an intermediate phenotype. All children and adult patients that were sarcopenic were also obese. These changes were significantly more pronounced in children with collagen VI deficiency than in children with Duchenne Muscular Dystrophy of the same ambulatory status. High molecular weight adiponectin and leptin were significantly increased in sera from children in the intermediate and BM group. Correlation analysis showed that the parameters of fat mass were negatively associated with motor function according to several validated outcome measures. In contrast, lean mass parameters correlated positively with physical performance and quality of life. Leptin and adiponectin circulating levels correlated positively with fat mass parameters and negatively with lean mass and thus may be relevant to the disease pathogenesis and as circulating markers. Taken together our results indicate that COL6-RM are characterized by specific changes in total fat mass and distribution which associate with disease severity, motor function, and quality of life and which are clinically meaningful and thus should be taken into consideration in the management of these patients

    Catálogo y distribución geográfica de los Odonatos en la Región de Murcia (SE España).

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    Se actualiza el catálogo y la distribución del orden Odonata en la Región de Murcia, comparándolo a uno anterior realizado en los años 50 del siglo XX. Los resultados indican que a mitad del siglo pasado se localizaron 40 especies en 17 localidades, mientras que las 2.087 citas recopiladas entre 1991-2017 confirman la presencia de 47 especies en 191 localidades. Se han identificado 11 nuevas especies para la Región de Murcia, que se pueden haber visto favorecidas por la construcción de charcas, embalses y otras infraestructuras para abastecer a las 225.000 ha de regadíos. De ellas, 9 especies se están expandiendo su área de distribución hacia el norte de Europa y/o Asia, efecto que podría estar relacionado con el proceso de cambio climático actual. Por el contrario, en la revisión actual no han sido detectadas 4 especies citadas en el estudio realizado a mediados del siglo XX

    Oxigenación con membrana extracorpórea en el paciente COVID-19: resultados del Registro Español ECMO-COVID de la Sociedad Española de Cirugía Cardiovascular y Endovascular (SECCE)

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    Background and aim: COVID-19 patients with severe heart or respiratory failure are potential candidates for extracorporeal membrane oxygenation (ECMO). Indications and management of these patients are unclear. Our aim is to describe the results of a prospective registry of COVID-19 patients treated with ECMO. Methods: An anonymous prospective registry of COVID-19 patients treated with veno-arterial (V-A) or veno-venous (V-V) ECMO was created on march 2020. Clinical, analytical and respiratory preimplantation variables, implantation data and post-implantation course data were recorded. The primary endpoint was all cause in-hospital mortality. Secondary events were functional recovery and the combined endpoint of mortality and functional recovery in patients followed at least 3 months after discharge. Results: Three hundred and sixty-six patients from 25 hospitals were analyzed, 347 V-V ECMO and 18 V-A ECMO patients (mean age 52.7 and 49.5 years respectively). Patients with V-V ECMO were more obese, had less frequently organ damage other than respiratory failure and needed less inotropic support; Thirty three percent of V-A ECMO and 34.9% of V-A ECMO were discharged (P = NS). Hospital mortality was non-significantly different, 56.2% versus 50.9% respectively, mainly during ECMO therapy and mostly due to multiorgan failure. Other 51 patients (14%) remained admitted. Mean follow-up was 196 +/- 101.7 days (95%CI: 170.8-221.6). After logistic regression, body weight (OR 0.967, 95%CI: 0.95-0.99, P = 0.004) and ECMO implantation in the own centre (OR 0.48, 95%CI: 0.27-0.88, P = 0.018) were protective for hospital mortality. Age (OR 1.063, 95%CI: 1.005-1.12, P = 0.032), arterial hypertension (3.593, 95%CI: 1.06-12.19, P = 0.04) and global (2.44, 95%CI: 0.27-0.88, P = 0.019), digestive (OR 4,23, 95%CI: 1.27-14.07, P = 0.019) and neurological (OR 4.66, 95%CI: 1.39-15.62, P = 0.013) complications during ECMO therapy were independent predictors of primary endpoint occurrence. Only the post-discharge day at follow-up was independent predictor of both secondary endpoints occurrence. Conclusions: Hospital survival of severely ill COVID-19 patients treated with ECMO is near 50%. Age, arterial hypertension and ECMO complications are predictors of hospital mortality, and body weight and implantation in the own centre are protective. Functional recovery is only predicted by the follow-up time after discharge. A more homogeneous management of these patients is warranted for clinical results and future research optimization. (C) 2022 Sociedad Espanola de Cirugia Cardiovascular y Endovascular. Published by Elsevier Espana, S.L.U

    Viral RNA load in plasma is associated with critical illness and a dysregulated host response in COVID‑19

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    Background. COVID-19 can course with respiratory and extrapulmonary disease. SARS-CoV-2 RNA is detected in respiratory samples but also in blood, stool and urine. Severe COVID-19 is characterized by a dysregulated host response to this virus. We studied whether viral RNAemia or viral RNA load in plasma is associated with severe COVID-19 and also to this dysregulated response. Methods. A total of 250 patients with COVID-19 were recruited (50 outpatients, 100 hospitalized ward patients and 100 critically ill). Viral RNA detection and quantification in plasma was performed using droplet digital PCR, targeting the N1 and N2 regions of the SARS-CoV-2 nucleoprotein gene. The association between SARS-CoV-2 RNAemia and viral RNA load in plasma with severity was evaluated by multivariate logistic regression. Correlations between viral RNA load and biomarkers evidencing dysregulation of host response were evaluated by calculating the Spearman correlation coefficients. Results. The frequency of viral RNAemia was higher in the critically ill patients (78%) compared to ward patients (27%) and outpatients (2%) (p < 0.001). Critical patients had higher viral RNA loads in plasma than non-critically ill patients, with non-survivors showing the highest values. When outpatients and ward patients were compared, viral RNAemia did not show significant associations in the multivariate analysis. In contrast, when ward patients were compared with ICU patients, both viral RNAemia and viral RNA load in plasma were associated with critical illness (OR [CI 95%], p): RNAemia (3.92 [1.183–12.968], 0.025), viral RNA load (N1) (1.962 [1.244–3.096], 0.004); viral RNA load (N2) (2.229 [1.382–3.595], 0.001). Viral RNA load in plasma correlated with higher levels of chemokines (CXCL10, CCL2), biomarkers indicative of a systemic inflammatory response (IL-6, CRP, ferritin), activation of NK cells (IL-15), endothelial dysfunction (VCAM-1, angiopoietin-2, ICAM-1), coagulation activation (D-Dimer and INR), tissue damage (LDH, GPT), neutrophil response (neutrophils counts, myeloperoxidase, GM-CSF) and immunodepression (PD-L1, IL-10, lymphopenia and monocytopenia). Conclusions. SARS-CoV-2 RNAemia and viral RNA load in plasma are associated with critical illness in COVID-19. Viral RNA load in plasma correlates with key signatures of dysregulated host responses, suggesting a major role of uncontrolled viral replication in the pathogenesis of this disease.This work was supported by awards from the Canadian Institutes of Health Research, the Canadian 2019 Novel Coronavirus (COVID-19) Rapid Research Funding initiative (CIHR OV2 – 170357), Research Nova Scotia (DJK), Atlantic Genome/Genome Canada (DJK), Li-Ka Shing Foundation (DJK), Dalhousie Medical Research Foundation (DJK), the “Subvenciones de concesión directa para proyectos y programas de investigación del virus SARS‐CoV2, causante del COVID‐19”, FONDO–COVID19, Instituto de Salud Carlos III (COV20/00110, CIBERES, 06/06/0028), (AT) and fnally by the “Convocatoria extraordinaria y urgente de la Gerencia Regional de Salud de Castilla y León, para la fnanciación de proyectos de investigación en enfermedad COVID-19” (GRS COVID 53/A/20) (CA). DJK is a recipient of the Canada Research Chair in Translational Vaccinology and Infammation. APT was funded by the Sara Borrell Research Grant CD018/0123 funded by Instituto de Salud Carlos III and co-fnanced by the European Development Regional Fund (A Way to Achieve Europe programme). The funding sources did not play any role neither in the design of the study and collection, not in the analysis, in the interpretation of data or in writing the manuscript

    The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

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    Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015

    Cambios socioculturales y consumo de las familias costarricenses

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    En este artículo se realiza una reflexión y análisis de la familia en general, vista como institución social que actúa como mediación entre las dinámicas macro y micro sociales, es decir, que en el ámbito de los mismos hogares confluyen los cambios sociales generales y las acciones de los individuos. El marco histórico general lo constituyen los cambios socioeconómicos, culturales y demográficos que ha experimentado Costa Rica en las últimas tres décadas; los cuales han influido en los estilos de vida que se expresan en diversos patrones de consumo, y que se analizan de acuerdo a las fases del ciclo de vida y el nivel socioeconómico de los hogares. Los hallazgos muestran en general que conforme las familias pasan por las diversas fases o etapas de su ciclo de vida, se producen cambios en sus patrones de consumo, los que al ser examinados por niveles de ingreso, reflejan las crecientes desigualdades socioeconómicas que caracterizan a la actual sociedad costarricense.This article reflects on and analyses the family in general, viewed like social institution that mediates among macro and micro social dynamics. In other words, the general social change and actions of individuals converge in the household. The general historical context constitutes the socioeconomic, cultural and demographic changes that Costa Rica has experienced in the last three decades. These changes have intluenced lifestyles and are expressed in different consumption patterns which are analyzed here according to the phases of the life cycle and the socioeconomic level of households. The general findings show how as farnilies go through the different phases or stages of their life cycle, changes take place in their consumption patterns. Those consumption pattern changes analyzed by income levels retlect the growing socioeconomic inequalities that characterize the current Costa Rican society.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Centro Centroamericano de Población (CCP
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