93 research outputs found

    Cartas a Adrián: el efecto mariposa: caos e incertidumbre en los seres vivos

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    Terapias génicas y eugenesia: Las nuevas fronteras de la medicina

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    Clonación y clonación humana: La parábola del sexto día

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    A long-period transiting substellar companion in the super-Jupiters to brown dwarfs mass regime and a prototypical warm-Jupiter detected by TESS

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    We report on the confirmation and follow-up characterization of two long-period transiting substellar companions on low-eccentricity orbits around TIC 4672985 and TOI-2529, whose transit events were detected by the TESS space mission. Ground-based photometric and spectroscopic follow up from different facilities, confirmed the substellar nature of TIC 4672985 b, a massive gas giant, in the transition between the super-Jupiters and brown-dwarfs mass regime. From the joint analysis we derived the following orbital parameters: P = 69.0480+0.0004−0.0005 d, Mp = 12.74+1.01−1.01 MJ, Rp =1.026+0.065−0.067 RJ and e = 0.018+0.004−0.004 . In addition, the RV time series revealed a significant trend at the ∼ 350 m s−1 yr−1level, which is indicative of the presence of a massive outer companion in the system. TIC 4672985 b is a unique example of a transiting substellar companion with a mass above the deuterium-burning limit, located beyond 0.1 AU and in a nearly circular orbit. These planetary properties are difficult to reproduce from canonical planet formation and evolution models. For TOI-2529 b, we obtained the following orbital parameters: P = 64.5949+0.0003−0.0003 d, Mp =2.340+0.197−0.195 MJ, Rp = 1.030+0.050−0.050 RJ and e = 0.021+0.024−0.015 , making this object a new example of a growing population of transiting warm giant planets

    A long-period transiting substellar companion in the super-Jupiters to brown dwarfs mass regime and a prototypical warm-Jupiter detected by TESS

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    We report on the confirmation and follow-up characterization of two long-period transiting substellar companions on low-eccentricity orbits around TIC 4672985 and TOI-2529, whose transit events were detected by the TESS space mission. Ground-based photometric and spectroscopic follow-up from different facilities, confirmed the substellar nature of TIC 4672985 b, a massive gas giant, in the transition between the super Jupiters and brown dwarfs mass regime. From the joint analysis we derived the following orbital parameters: P = 69.0480 d, Mp = 12.74 Mjup, Rp = 1.026 Rjup and e = 0.018. In addition, the RV time series revealed a significant trend at the 350 m/s/yr level, which is indicative of the presence of a massive outer companion in the system. TIC 4672985 b is a unique example of a transiting substellar companion with a mass above the deuterium-burning limit, located beyond 0.1 AU and in a nearly circular orbit. These planetary properties are difficult to reproduce from canonical planet formation and evolution models. For TOI-2529 b, we obtained the following orbital parameters: P = 64.5949 d, Mp = 2.340 Mjup, Rp = 1.030 Rjup and e = 0.021, making this object a new example of a growing population of transiting warm giant planets.Comment: Accepted in A&

    The discovery and follow-up of four transiting short-period sub-Neptunes orbiting M dwarfs

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    Sub-Neptunes with radii of 2–3 R⊕ are intermediate in size between rocky planets and Neptune-sized planets. The orbital properties and bulk compositions of transiting sub-Neptunes provide clues to the formation and evolution of close-in small planets. In this paper, we present the discovery and follow-up of four sub-Neptunes orbiting M dwarfs (TOI-782, TOI-1448, TOI-2120, and TOI-2406), three of which were newly validated by ground-based follow-up observations and statistical analyses. TOI-782 b, TOI-1448 b, TOI-2120 b, and TOI-2406 b have radii of Rp = 2.740 +0.082-0.079 R⊕, 2.769+0.073-0.068 R⊕, 2.120 ± 0.067 R⊕, and 2.830+0.068-0.066 R⊕ and orbital periods of P = 8.02, 8.11, 5.80, and 3.08 days, respectively. Doppler monitoring with the Subaru/InfraRed Doppler instrument led to 2σ upper limits on the masses of <19.1 M⊕, <19.5 M⊕, <6.8 M⊕, and <15.6 M⊕ for TOI-782 b, TOI-1448 b, TOI-2120 b, and TOI-2406 b, respectively. The mass–radius relationship of these four sub-Neptunes testifies to the existence of volatile material in their interiors. These four sub-Neptunes, which are located above the so-called "radius valley," are likely to retain a significant atmosphere and/or an icy mantle on the core, such as a water world. We find that at least three of the four sub-Neptunes (TOI-782 b, TOI-2120 b, and TOI-2406 b), orbiting M dwarfs older than 1 Gyr, are likely to have eccentricities of e ∼ 0.2–0.3. The fact that tidal circularization of their orbits is not achieved over 1 Gyr suggests inefficient tidal dissipation in their interiors.Peer reviewe

    CONSENSO SOBRE EL USO DE PROTEÍNA EN EL PACIENTE CRÍTICO – ACNC

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    El paciente crítico tiene una pérdida de masa muscular significativa, observando frecuentemente sarcopenia en estos pacientes. Su presencia aumenta los desenlaces adversos, estancias hospitalarias, mayor riesgo de infecciones, aumento del tiempo de asistencia ventilatoria mecánica, mayor discapacidad al alta hospitalaria, menor posibilidad del retorno normal a la vida habitual de los pacientes, incremento en gastos en salud y mayor mortalidad. Objetivo: Indicar el uso oportuno y adecuado de la proteína en el paciente crítico. Métodos: la Asociación Colombiana De Nutrición Clínica (ACNC) y la Asociación Colombiana de Medicina Critica y Cuidados Intensivos (AMCI) mediante metodología de consenso realizaron unas recomendaciones con un grupo de expertos. Resultados: 46 recomendaciones fueron aprobadas con consenso superior al 80%. Conclusiones: La intervención óptima proteica temprana y progresiva en el paciente crítico, es importante para obtener los mejores desenlaces clínicos, disminuir complicaciones e impactar en costos de atención hospitalaria.

    CONSENSO SOBRE O USO DE PROTEÍNA EM PACIENTES CRÍTICOS – ACNC

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    The critical patient has a significant loss of muscle mass, frequently observing sarcopenia in these patients. Its presence increases adverse outcomes, hospital stays, increased risk of infections, increased time on mechanical ventilatory assistance, greater disability at hospital discharge, less possibility of return to normal life for patients, increased health costs, and higher mortality. Objective: Indicate the opportune and adequate use of the protein in the critically ill patient. Methods: the Colombian Association of Clinical Nutrition (ACNC) and the Colombian Association of Critical Medicine and Intensive Care (AMCI), using a consensus methodology, made recommendations with a group of experts. Results: 46 recommendations were approved with a consensus greater than 80%. Conclusions: Optimal early and progressive protein intervention in critically ill patients is important to obtain the best clinical outcomes, reduce complications, and have an impact on hospital care costs.El paciente crítico tiene una pérdida de masa muscular significativa, observando frecuentemente sarcopenia en estos pacientes. Su presencia aumenta los desenlaces adversos, estancias hospitalarias, mayor riesgo de infecciones, aumento del tiempo de asistencia ventilatoria mecánica, mayor discapacidad al alta hospitalaria, menor posibilidad del retorno normal a la vida habitual de los pacientes, incremento en gastos en salud y mayor mortalidad. Objetivo: Indicar el uso oportuno y adecuado de la proteína en el paciente crítico. Métodos: la Asociación Colombiana De Nutrición Clínica (ACNC) y la Asociación Colombiana de Medicina Critica y Cuidados Intensivos (AMCI) mediante metodología de consenso realizaron unas recomendaciones con un grupo de expertos. Resultados: 46 recomendaciones fueron aprobadas con consenso superior al 80%. Conclusiones: La intervención óptima proteica temprana y progresiva en el paciente crítico, es importante para obtener los mejores desenlaces clínicos, disminuir complicaciones e impactar en costos de atención hospitalaria.&nbsp;O paciente crítico apresenta perda importante de massa muscular, observando-se frequentemente sarcopenia nesses pacientes. Sua presença aumenta os desfechos adversos, internações hospitalares, aumento do risco de infecções, aumento do tempo de assistência ventilatória mecânica, maior incapacidade na alta hospitalar, menor possibilidade de retorno à vida normal dos pacientes, aumento dos custos de saúde e maior mortalidade. Objetivo: Indicar o uso oportuno e adequado da proteína no paciente crítico. Métodos: a Associação Colombiana de Nutrição Clínica (ACNC) e a Associação Colombiana de Medicina Crítica e Terapia Intensiva (AMCI), utilizando uma metodologia de consenso, fizeram recomendações com um grupo de especialistas. Resultados: 46 recomendações foram aprovadas com consenso superior a 80%. Conclusões: A intervenção proteica precoce e progressiva ideal em pacientes críticos é importante para obter os melhores resultados clínicos, reduzir complicações e impactar nos custos hospitalares

    Consistent patterns of common species across tropical tree communities

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    Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe
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