17 research outputs found

    Alternativas de desarrollo agropecuario con proyección sostenible para el distrito de riego del Zulia y su zona de influencia

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    La asociación de usuarios del Distrito de Adecuación de Tierras de Gran Escala del Río Zulia (ASOZULIA) Norte de Santander, con un área de influencia de 45.536 hectáreas, está interesada en la planificación productiva de su territorio. Dentro de sus actividades agropecuarias se encuentran el arroz (12.000 a 17.000 ha), la palma de aceite (1.534 ha), cítricos (limón, naranja; 346 ha), caña de azúcar (100 ha) y la ganadería. Su principal sistema de producción durante más de 50 años es el cultivo de arroz, sistema que presenta reducción de la productividad (7 a 3 tha), degradación del suelo y problemas de plagas y enfermedades, debido entre otros al uso continuo del fangueo como sistema de preparación de suelos. Adicionalmente, a pesar de tener el distrito de riego del río Zulia una concesión de 13,5 m3.s1, en épocas de verano la oferta hidrica es mucho menor como, por ejemplo, la correspondiente a los meses de febrero a marzo de 2016, con un caudal en la bocatoma del distrito de 10,8 m3s'y una captación real del distrito de solo 6 m.s' Asimismo, la construcción del nuevo acueducto para el área metropolitana de la ciudad de Cúcuta tomará 2,95 m3s del caudal antes de la bocatoma que provee agua al distrito, lo que disminuirá aún más la disponibilidad de agua para riego en esa región. Por lo anterior, se requiere la recuperación de los suelos para el establecimiento de nuevos sistemas productivos que demanden un menor consumo de agua y sean una alternativa viable para los productores.Acelga-Remolacha de hoja, Beta vulgaris var. Cicl

    Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations

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    Context. A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. Aims. We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. Methods. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range similar to 8 km to similar to 190 km, corresponding to pressure levels from 9 mu bar down to a few nanobars. Results. (i) A pressure of 1.18 +/- 0.03 mu bar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 mu bar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude.J.M.O. acknowledges financial support from the Portuguese Foundation for Science and Technology (FCT) and the European Social Fund (ESF) through the PhD grant SFRH/BD/131700/2017. The work leading to these results has received funding from the European Research Council under the European Community's H2020 2014-2021 ERC grant Agreement nffi 669416 "Lucky Star". We thank S. Para who supported some travels to observe the 5 October 2017 occultation. T.B. was supported for this research by an appointment to the National Aeronautics and Space Administration (NASA) Post-Doctoral Program at the Ames Research Center administered by Universities Space Research Association (USRA) through a contract with NASA. We acknowledge useful exchanges with Mark Gurwell on the ALMA CO observations. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium).Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. J.L.O., P.S.-S., N.M. and R.D. acknowledge financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709), they also acknowledge the financial support by the Spanish grant AYA-2017-84637-R and the Proyecto de Excelencia de la Junta de Andalucia J.A. 2012-FQM1776. The research leading to these results has received funding from the European Union's Horizon 2020 Research and Innovation Programme, under Grant Agreement no. 687378, as part of the project "Small Bodies Near and Far" (SBNAF). P.S.-S. acknowledges financial support by the Spanish grant AYA-RTI2018-098657-J-I00 "LEO-SBNAF". The work was partially based on observations made at the Laboratorio Nacional de Astrofisica (LNA), Itajuba-MG, Brazil. The following authors acknowledge the respective CNPq grants: F.B.-R. 309578/2017-5; R.V.-M. 304544/2017-5, 401903/2016-8; J.I.B.C. 308150/2016-3 and 305917/2019-6; M.A. 427700/20183, 310683/2017-3, 473002/2013-2. This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -Brasil (CAPES) -Finance Code 001 and the National Institute of Science and Technology of the e-Universe project (INCT do e-Universo, CNPq grant 465376/2014-2). G.B.R. acknowledges CAPES-FAPERJ/PAPDRJ grant E26/203.173/2016 and CAPES-PRINT/UNESP grant 88887.571156/2020-00, M.A. FAPERJ grant E26/111.488/2013 and A.R.G.Jr. FAPESP grant 2018/11239-8. B.E.M. thanks CNPq 150612/2020-6 and CAPES/Cofecub-394/2016-05 grants. Part of the photometric data used in this study were collected in the frame of the photometric observations with the robotic and remotely controlled telescope at the University of Athens Observatory (UOAO; Gazeas 2016). The 2.3 m Aristarchos telescope is operated on Helmos Observatory by the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing of the National Observatory of Athens. Observations with the 2.3 m Aristarchos telescope were carried out under OPTICON programme. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 730890. This material reflects only the authors views and the Commission is not liable for any use that may be made of the information contained therein. The 1. 2m Kryoneri telescope is operated by the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing of the National Observatory of Athens. The Astronomical Observatory of the Autonomous Region of the Aosta Valley (OAVdA) is managed by the Fondazione Clement Fillietroz-ONLUS, which is supported by the Regional Government of the Aosta Valley, the Town Municipality of Nus and the "Unite des Communes valdotaines Mont-Emilius". The 0.81 m Main Telescope at the OAVdA was upgraded thanks to a Shoemaker NEO Grant 2013 from The Planetary Society. D.C. and J.M.C. acknowledge funds from a 2017 'Research and Education' grant from Fondazione CRT-Cassa di Risparmio di Torino. P.M. acknowledges support from the Portuguese Fundacao para a Ciencia e a Tecnologia ref. PTDC/FISAST/29942/2017 through national funds and by FEDER through COMPETE 2020 (ref. POCI010145 FEDER007672). F.J. acknowledges Jean Luc Plouvier for his help. S.J.F. and C.A. would like to thank the UCL student support observers: Helen Dai, Elise Darragh-Ford, Ross Dobson, Max Hipperson, Edward Kerr-Dineen, Isaac Langley, Emese Meder, Roman Gerasimov, Javier Sanjuan, and Manasvee Saraf. We are grateful to the CAHA, OSN and La Hita Observatory staffs. This research is partially based on observations collected at Centro Astronomico HispanoAleman (CAHA) at Calar Alto, operated jointly by Junta de Andalucia and Consejo Superior de Investigaciones Cientificas (IAA-CSIC). This research was also partially based on observation carried out at the Observatorio de Sierra Nevada (OSN) operated by Instituto de Astrofisica de Andalucia (CSIC). This article is also based on observations made with the Liverpool Telescope operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council. Partially based on observations made with the Tx40 and Excalibur telescopes at the Observatorio Astrofisico de Javalambre in Teruel, a Spanish Infraestructura Cientifico-Tecnica Singular (ICTS) owned, managed and operated by the Centro de Estudios de Fisica del Cosmos de Aragon (CEFCA). Tx40 and Excalibur are funded with the Fondos de Inversiones de Teruel (FITE). A.R.R. would like to thank Gustavo Roman for the mechanical adaptation of the camera to the telescope to allow for the observation to be recorded. R.H., J.F.R., S.P.H. and A.S.L. have been supported by the Spanish projects AYA2015-65041P and PID2019-109467GB-100 (MINECO/FEDER, UE) and Grupos Gobierno Vasco IT1366-19. Our great thanks to Omar Hila and their collaborators in Atlas Golf Marrakech Observatory for providing access to the T60cm telescope. TRAPPIST is a project funded by the Belgian Fonds (National) de la Recherche Scientifique (F.R.S.-FNRS) under grant PDR T.0120.21. TRAPPIST-North is a project funded by the University of Liege, and performed in collaboration with Cadi Ayyad University of Marrakesh. E.J. is a FNRS Senior Research Associate

    Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

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    Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p<0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (<1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (<1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

    EDUCACIÓN AMBIENTAL Y SOCIEDAD. SABERES LOCALES PARA EL DESARROLLO Y LA SUSTENTABILIDAD

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    Este texto contribuye al análisis científico de varias áreas del conocimiento como la filosofía social, la patología, la educación para el cuidado del medio ambiente y la sustentabilidad que inciden en diversas unidades de aprendizaje de la Licenciatura en Educación para la Salud y de la Maestría en Sociología de la SaludLas comunidades indígenas de la sierra norte de Oaxaca México, habitan un territorio extenso de biodiversidad. Sin que sea una área protegida y sustentable, la propia naturaleza de la región ofrece a sus visitantes la riqueza de la vegetación caracterizada por sus especies endémicas que componen un paisaje de suma belleza

    A global experiment on motivating social distancing during the COVID-19 pandemic

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    Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

    Urban and semi-urban mosquitoes of Mexico City: A risk for endemic mosquito-borne disease transmission.

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    Since past century, vector-borne diseases have been a major public health concern in several states of Mexico. However, Mexico City continues to be free of endemic mosquito-borne viral diseases. The city is the most important politic and economic state of Mexico and one of the most important city of Latin America. Its subtropical highland climate and high elevation (2240 masl) had historically made the occurrence of Aedes species unlikely. However, the presence of other potential disease vectors (Culex spp, Culiseta spp), and the current intermittent introductions of Aedes aegypti, have revealed that control programs must adopt routine vector surveillance in the city. In this study, we provide an updated species list from a five-years of vector surveillance performed in Mexico City. A total of 18,553 mosquito larvae were collected. Twenty-two species from genus Culex, Aedes, Culiseta, Anopheles, Lutzia and Uranotaenia were observed. Nine new mosquito records for the city were found. Ae. albopictus was recorded for the first time in Mexico City. Interestingly, a new record, Ae. epactius was the most frequent species reported. Cx. pipiens quinquefasciatus exhibited the highest number of individuals collected. We detected six areas which harbor the highest mosquito species records in the city. Cemeteries included 68.9% of our collection sites. Temporarily ponds showed the highest species diversity. We detected an increasing presence of Ae. aegypti, which was detected for three consecutive years (2015-2017), predominantly in the warmer microclimates of the city. We found a possible correlation between increasing temperature and Ae. aegypti and Ae. albopictus expanding range. This study provides a starting point for developing strategies related to environmental management for mosquito control. The promotion of mosquito control practices through community participation, mass media and education programmes in schools should be introduced in the city

    Characterizing environmental suitability of Aedes albopictus (Diptera: Culicidae) in Mexico based on regional and global niche models

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    The Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae), is an invasive species and a vector of numerous human pathogens, including chikungunya, dengue, yellow fever, and Zika viruses. This mosquito had been reported from 36 geographic locations in Mexico by 2005, increasing to 101 locations by 2010 and 501 locations (spanning 16 states) by 2016. Here we modeled the occupied niche for Ae. albopictus in Mexico to characterize the environmental conditions related to its presence, and to generate updated environmental suitability maps. The predictors with the greatest contribution to characterizing the occupied niche for Ae. albopictus were NDVI and annual mean temperature. We also estimated the environmental suitability for Ae. albopictus in regions of the country where it has not been documented yet, by means of: 1) transferring its occupied niche model to these regions and 2) modeling its fundamental niche using global data. Our models will help vector control and public health institutions to identify areas where Ae. albopictus has not yet been recorded but where it may be present. We emphasize that most of Mexico has environmental conditions that potentially allow the survival of Ae. albopictus, which underscores the need for systematic mosquito monitoring in all states of the country

    Covid-19: consecuencias y desafíos en la economía colombiana. Una mirada desde las universidades

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    Este libro reúne diferentes hallazgos, perspectivas y efectos ante un fenómeno que, más de un año después, todavía representa un reto científico, médico y social para todos. Igualmente, esta obra representa el objetivo de la Red Investigadores de Economía: aunar esfuerzos para encontrar respuestas y para fortalecer la investigación en el país, aumentar la difusión de trabajos de calidad y propiciar el encuentro entre académicos, universidades y el Banco de la República. Las investigaciones expuestas en este libro pasaron por un proceso de selección por parte del comité científico, asegurando que hubiese una pluralidad de miradas y de instituciones educativas, además del Banco, donde se relacionaran los efectos de la pandemia y la actividad económica en el país, las consecuencias sociales y regionales. El texto está dividido en cuatro partes. En la primera se hace un análisis macroeconómico de los efectos de la pandemia; para ello se examinan los efectos de la emergencia sanitaria a nivel nacional y regional mediante modelos macroeconómicos que permiten obtener respuestas ante preguntas muy relevantes. La segunda sección trata sobre el impacto en el mercado laboral, el efecto del Covid-19 en la distribución del ingreso y el efecto de corto plazo en el mercado urbano. La tercera parte aborda los efectos de la pandemia en los agentes económicos y en otros mercados. Ello incluye la exposición del empleo al Covid-19, la vulnerabilidad económica de los hogares en el país y su respuesta en el consumo, patrones de actividad laboral y salud mental, efectos en la educación, inseguridad alimentaria de la población migrante, entre otros. Por último, el cuarto segmento hace un énfasis especial en los efectos diferenciales entre las regiones del país y la heterogeneidad de dicho impacto; para ello se analizan temas de informalidad, vulnerabilidad, fuerza de trabajo disponible, entre otros, en distintas regiones del país

    Efficacy and safety of the CVnCoV SARS-CoV-2 mRNA vaccine candidate in ten countries in Europe and Latin America (HERALD): a randomised, observer-blinded, placebo-controlled, phase 2b/3 trial

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    Background: Additional safe and efficacious vaccines are needed to control the COVID-19 pandemic. We aimed to analyse the efficacy and safety of the CVnCoV SARS-CoV-2 mRNA vaccine candidate. Methods: HERALD is a randomised, observer-blinded, placebo-controlled, phase 2b/3 clinical trial conducted in 47 centres in ten countries in Europe and Latin America. By use of an interactive web response system and stratification by country and age group (18–60 years and ≥61 years), adults with no history of virologically confirmed COVID-19 were randomly assigned (1:1) to receive intramuscularly either two 0·6 mL doses of CVnCoV containing 12 μg of mRNA or two 0·6 mL doses of 0·9% NaCl (placebo) on days 1 and 29. The primary efficacy endpoint was the occurrence of a first episode of virologically confirmed symptomatic COVID-19 of any severity and caused by any strain from 15 days after the second dose. For the primary endpoint, the trial was considered successful if the lower limit of the CI was greater than 30%. Key secondary endpoints were the occurrence of a first episode of virologically confirmed moderate-to-severe COVID-19, severe COVID-19, and COVID-19 of any severity by age group. Primary safety outcomes were solicited local and systemic adverse events within 7 days after each dose and unsolicited adverse events within 28 days after each dose in phase 2b participants, and serious adverse events and adverse events of special interest up to 1 year after the second dose in phase 2b and phase 3 participants. Here, we report data up to June 18, 2021. The study is registered at ClinicalTrials.gov, NCT04652102, and EudraCT, 2020–003998–22, and is ongoing. Findings: Between Dec 11, 2020, and April 12, 2021, 39 680 participants were enrolled and randomly assigned to receive either CVnCoV (n=19 846) or placebo (n=19 834), of whom 19 783 received at least one dose of CVnCoV and 19 746 received at least one dose of placebo. After a mean observation period of 48·2 days (SE 0·2), 83 cases of COVID-19 occurred in the CVnCoV group (n=12 851) in 1735·29 person-years and 145 cases occurred in the placebo group (n=12 211) in 1569·87 person-years, resulting in an overall vaccine efficacy against symptomatic COVID-19 of 48·2% (95·826% CI 31·0–61·4; p=0·016). Vaccine efficacy against moderate-to-severe COVID-19 was 70·7% (95% CI 42·5–86·1; CVnCoV 12 cases in 1735·29 person-years, placebo 37 cases in 1569·87 person-years). In participants aged 18–60 years, vaccine efficacy against symptomatic disease was 52·5% (95% CI 36·2–64·8; CVnCoV 71 cases in 1591·47 person-years, placebo, 136 cases in 1449·23 person-years). Too few cases occurred in participants aged 61 years or older (CVnCoV 12, placebo nine) to allow meaningful assessment of vaccine efficacy. Solicited adverse events, which were mostly systemic, were more common in CVnCoV recipients (1933 [96·5%] of 2003) than in placebo recipients (1344 [67·9%] of 1978), with 542 (27·1%) CVnCoV recipients and 61 (3·1%) placebo recipients reporting grade 3 solicited adverse events. The most frequently reported local reaction after any dose in the CVnCoV group was injection-site pain (1678 [83·6%] of 2007), with 22 grade 3 reactions, and the most frequently reported systematic reactions were fatigue (1603 [80·0%] of 2003) and headache (1541 [76·9%] of 2003). 82 (0·4%) of 19 783 CVnCoV recipients reported 100 serious adverse events and 66 (0·3%) of 19 746 placebo recipients reported 76 serious adverse events. Eight serious adverse events in five CVnCoV recipients and two serious adverse events in two placebo recipients were considered vaccination-related. None of the fatal serious adverse events reported (eight in the CVnCoV group and six in the placebo group) were considered to be related to study vaccination. Adverse events of special interest were reported for 38 (0·2%) participants in the CVnCoV group and 31 (0·2%) participants in the placebo group. These events were considered to be related to the trial vaccine for 14 (<0·1%) participants in the CVnCoV group and for five (<0·1%) participants in the placebo group. Interpretation: CVnCoV was efficacious in the prevention of COVID-19 of any severity and had an acceptable safety profile. Taking into account the changing environment, including the emergence of SARS-CoV-2 variants, and timelines for further development, the decision has been made to cease activities on the CVnCoV candidate and to focus efforts on the development of next-generation vaccine candidates. Funding: German Federal Ministry of Education and Research and CureVac
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