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With high equilibrium temperatures and tidally locked rotation, ultra-hot Jupiters (UHJs) are unique laboratories within which to probe extreme atmospheric physics and chemistry. In this paper, we present high-resolution dayside spectroscopy of the UHJ WASP-189 b obtained with the new Gemini High-resolution Optical SpecTrograph (GHOST) at the Gemini South Observatory. The observations, which cover 3 hr of post-eclipse orbital phases, were obtained during the instrument’s System Verification run. We detect the planet’s atmosphere via the Doppler cross-correlation technique, and recover a detection of neutral iron in the planet’s dayside atmosphere at a significance of 7.5 σ in the red arm of the data, verifying the presence of a thermal inversion. We also investigate the presence of other species in the atmosphere and discuss the implications of model injection/recovery tests. These results represent the first atmospheric characterization of an exoplanet with GHOST’s high-resolution mode, and demonstrate the potential of this new instrument in detecting and studying ultra-hot exoplanet atmospheres.

Abstract Background Since the 1990’s, afforestation programs in the páramo have been implemented to offset carbon emissions through carbon sequestration, mainly using pine plantations. However, several studies have indicated that after the establishment of pine plantations in grasslands, there is an alteration of carbon pools including a decrease of the soil organic carbon (SOC) pool. The aim of this study is to investigate the impact of the establishment of pine plantations on the carbon stocks in different altitudes of the páramo ecosystem of South Ecuador. Results At seven locations within an elevational gradient from 2780 to 3760 m a.s.l., we measured and compared carbon stocks of three types of land use: natural grassland, grazed páramo, and Pinus patula Schlltdl. & Cham. plantation sites. For a more accurate estimation of pine tree carbon, we developed our own allometric equations. There were significant (p

En marzo del 2017 la Quebrada San Ildefonso, Trujillo, Perú, se activó como consecuencia de las precipitaciones pluviales generadas por el evento climático denominado El Niño Costero 2017 impactando la infraestructura urbana en la trayectoria de su cauce. El presente estudio tuvo como objetivo demostrar la relación existente entre los factores ambientales: presión atmosférica y temperatura ambiental en la fluctuación del nivel freático de la quebrada San Ildefonso determinando que la variación de unos pocos hectopascales (hPa) de presión, así como el incremento de la temperatura influyen en la fluctuación del nivel freático expuesto bajo la superficie del terreno. La metodología consistió en la medición de los parámetros ambientales durante los años 2018 y nivel de la napa freática de un pozo artesiano en desuso ubicado en el cauce de la quebrada durante los meses de enero a julio 2019. Los datos fueron tomados desde la superficie del terreno hasta el nivel de agua dentro del pozo cada seis horas, acorde a la oscilación máxima y mínima de la marea barométrica; simultáneamente se registraron la temperatura de aire, del agua y suelo. Se concluye que la presión atmosférica y temperatura influyen en el ascenso y descenso diario del nivel del agua subterránea de la quebrada de San Ildefonso.

We report on a chemo-dynamical analysis of SPLUS J142445.34−254247.1 (SPLUS J1424−2542), an extremely metal-poor halo star enhanced in elements formed by the rapid neutron-capture process ( r -process). This star was first selected as a metal-poor candidate from its narrowband S-PLUS photometry and followed up spectroscopically in medium resolution with Gemini-South/GMOS, which confirmed its low-metallicity status. High-resolution spectroscopy was gathered with GHOST at Gemini-South, allowing for the determination of the chemical abundances for 36 elements, from carbon to thorium. At [Fe/H] = −3.39, SPLUS J1424−2542 is one of the lowest-metallicity stars with measured Th and has the highest $\mathrm{log}\epsilon (\mathrm{Th}/\mathrm{Eu})$ observed to date, making it part of the “actinide-boost” category of r -process–enhanced stars. The analysis presented here suggests that the gas cloud from which SPLUS J1424−2542 formed must have been enriched by at least two progenitor populations. The light-element ( Z ≤ 30) abundance pattern is consistent with the yields from a supernova explosion of metal-free stars with 11.3–13.4 M _⊙ , and the heavy-element ( Z ≥ 38) abundance pattern can be reproduced by the yields from a neutron star merger (1.66 M _⊙ and 1.27 M _⊙ ) event. A kinematical analysis also reveals that SPLUS J1424−2542 is a low-mass, old halo star with a likely in situ origin, not associated with any known early merger events in the Milky Way.

The Gemini High-resolution Optical SpecTrograph (GHOST) is the newest high-resolution spectrograph to be developed for a large-aperture telescope, recently deployed and commissioned at the Gemini-South telescope. In this paper, we present the first science results from the GHOST spectrograph taking during its commissioning runs. We have observed the bright metal-poor benchmark star HD 122563, along with two stars in the ultrafaint dwarf galaxy Reticulum II (Ret ii ), one of which was previously identified as a candidate member, but did not have a previous detailed chemical abundance analysis. We find that this candidate (GDR3 0928) to be a bona fide member of Ret ii , and from a spectral synthesis analysis it is also revealed to be a CEMP- r star, with significant enhancements in several light elements (C, N, O, Na, Mg, and Si), in addition to featuring an r -process enhancement like many other Ret ii stars. The light-element enhancements in this star resemble the abundance patterns seen in the CEMP-no stars of other ultrafaint dwarf galaxies, and are thought to have been produced by an independent source from the r -process. These unusual abundance patterns are thought to be produced by faint supernovae, which may be produced by some of the earliest generations of stars.

Corn stover dry matter loss effects variability for biofuel conversion facility and technology sustainability. This research seeks to understand the dynamic mechanisms of the thermal system, organic matter loss, and microbial heat generation in corn stover storage operations through system dynamics, a mathematical modeling approach, and response analysis to improve the system performance. This study considers epistemic uncertainties including cardinal temperatures of microbial respiratory activity, specific degradation rate, heat evolution per unit substrate degraded, and thermal conductivity in corn stover storage reactors. These uncertainties were managed through calibration, a process of improving the agreement between the computational and benchmark experimental results by adjusting the parameters of the model. Model calibration successfully predicted the temperature of the system as quantified by the mean absolute error, 0.6°C, relative to the experimental work. The model and experimental dry matter loss after 30 days of storage were 5.1% and 4.9 ± 0.28%. The model was further validated using additional experimental results to ensure that the model accurately represented the system. Model validation obtained a temperature mean absolute relative error of 0.9 ± 0.3°C and dry matter loss relative error of 3.1 ± 1.5%. This study presents a robust prediction of corn stover storage temperature and demonstrates that an understanding of carbon sources, microbial communities, and lag-phase evolution in bi-phasic growth are essential for the prediction of organic matter preservation in corn stover storage systems under environment’s variation.

En 2019, en la cuidad de Wuhan, China, se detectaron pacientes infectados con un nuevo coronavirus denominado 2019-nCoV, hoy SARS-CoV-2. El alarmante crecimiento de esta pandemia hace necesario conocer e implementar métodos de diagnóstico confiables para detectar y tratar adecuadamente a los pacientes, lo que contribuirá a frenar la propagación de la enfermedad. La necesidad de tener profesionales entrenados en la toma de muestras, en las buenas prácticas de laboratorio clínico y en el manejo de técnicas moleculares y hematológicas es de suma importancia para identificar adecuadamente la infección con este virus. La estandarización de los protocolos de obtención, traslado y almacenamiento de la muestra es igualmente relevante para detener la expansión de la pandemia de COVID-19 causada por el SARS-CoV-2.

La humanidad se enfrenta, en la actualidad, a un reto que no diferencia fronteras, ideologías, sistemas socioeconómicos, etnias, religiones o culturas. Es una guerra que nos une como especie biológica, en la que las armas fundamentales provienen de la investigación puesta al servicio de los sistemas de salud. En esta guerra los gobiernos y las organizaciones internacionales de salud definen la estrategia; mientras que los sistemas de salud y las fuerzas del orden, de la mano de la ciudadanía, concretan las acciones y libran cada una de las batallas. Sin embargo, el más importante de los enfrentamientos se realiza en el interior de cada uno de nosotros. Como Perseo enfrentó a Hades en una batalla de titanes para evitar que convirtiera la Tierra en un infierno, el sistema inmune pone en marcha una poderosa maquinaria en la que moléculas y células del sistema innato y adquirido actúan de manera coordinada para combatir al SARS-CoV-2. Una maquinaria que sigue un guion escrito por la evolución, y que deja en nuestro sistema de defensa una memoria que nos fortalecerá como especie para enfrentar futuros Hades. Este trabajo resume la valiosa información que se ha publicado en los últimos meses respecto al coronavirus SARS-CoV-2 en su interacción con el sistema inmune. Se incluyen aspectos relacionados con la detección de la respuesta inmune como herramienta para el diagnóstico de esta infección, y la manipulación del sistema inmune en la prevención o el tratamiento de la misma.

To recreate or substitute tissue in vivo is a complicated endeavor that requires biomaterials that can mimic the natural tissue environment. Gelatin methacrylate (GelMA) is created through covalent bonding of naturally derived polymer gelatin and methacrylic groups. Due to its biocompatibility, GelMA receives a lot of attention in the tissue engineering research field. Additionally, GelMA has versatile physical properties that allow a broad range of modifications to enhance the interaction between the material and the cells. In this review, we look at recent modifications of GelMA with naturally derived polymers, nanomaterials, and growth factors, focusing on recent developments for vascular tissue engineering and wound healing applications. Compared to polymers and nanoparticles, the modifications that embed growth factors show better mechanical properties and better cell migration, stimulating vascular development and a structure comparable to the natural-extracellular matrix.

During the 1980s, reforestation programs using exotic species (Pinus spp.) were established in the páramo ecosystem of Ecuador. The aims of this study were: (1) to compare the natural regeneration between pine plantations (Pi) and natural grassland (NG) across an elevational gradient and (2) to identify the attributes of Pi and soil properties that were influencing herbaceous and woody plant composition and their plant cover. In total, six independent Pinus patula (Schltdl. & Cham. plantations (two per each elevation) were selected and distributed in an elevational range (3200−3400, 3400−3600, 3600−3800 m a.s.l.). Adjacent to Pi, plots in NG were established for recording natural regeneration. Both, namely the attributes and the soil samples, were measured in Pi. The results showed that natural regeneration differs significantly between both types of vegetation. As expected, NG holds more plant diversity than Pi; the elevational range showed a clear tendency that there was more herbaceous richness when elevation range increases, while the opposite was found for woody species. Moreover, attributes of Pi influenced herbaceous and woody vegetation, when saturated hydraulic conductivity (Ksat) in the soil, basal area (BA) and canopy density (CD) increased, herbaceous species richness and its cover decreseased; and when Ksat and the acidity in the soil increased, woody plants richness and its cover decreased. The plantations have facilitated the establishment of shade tolerant species. More studies are needed to evaluate if removal with adequate management of pine plantations can improve the restoration and conservation of the native vegetation of the páramo ecosystem.

The dry forest of southern Ecuador and northern Perú (called the Tumbesian region) is known for its high diversity, endemism, and healthy conservation state. Nevertheless, the forest is exposed to many threats linked with human activities. To understand the effects of these threats, which have not been appropriately assessed, we pose two questions: (a) What are the diversity and structural situations of the forest? (b) Are anthropogenic activities affecting the composition and structure of the forest? The assessed factors were species richness, diversity, species similarity, abundance, and density. Forest information was obtained from 72 plots (total area 25.92 ha) randomly placed to cover a wide range of stand densities (from 200 to 1100 m a.s.l.). After constructing linear mixed models and selecting the most influential one, we determined the individual influences of 12 predictors. The human pressure index (HPI) was the most negative predictor of forest health, and annual precipitation was the most important abiotic predictor of good health conditions. Livestock grazing did not significantly change the diversity and structure of mature forest. The mean annual temperature and stoniness influenced only the basal area and number of individuals, respectively. The species composition in our study area was not affected by the HPI, but was strongly predicted by annual precipitation.

Andean ecosystems provide important ecosystem services including streamflow regulation and carbon sequestration, services that are controlled by the water retention properties of the soils. Even though these soils have been historically altered by pine afforestation and grazing, little research has been dedicated to the assessment of such impacts at local or regional scales. To partially fill this knowledge gap, we present an evaluation of the impacts of pine plantations and grazing on the soil hydro-physical properties and soil organic matter (SOM) of high montane forests and páramo in southern Ecuador, at elevations varying between 2705 and 3766 m a.s.l. In total, seven study sites were selected and each one was parceled into undisturbed and altered plots with pine plantation and grazing. Soil properties were characterized at two depths, 0–10 and 10–25 cm, and differences in soil parameters between undisturbed and disturbed plots were analyzed versus factors such as ecosystem type, sampling depth, soil type, elevation, and past/present land management. The main soil properties affected by land use change are the saturated hydraulic conductivity (Ksat), the water retention capacity (pF 0 to 2.52), and SOM. The impacts of pine afforestation are dependent on sampling depth, ecosystem type, plantation characteristics, and previous land use, while the impacts of grazing are primarily dependent on sampling depth and land use management (grazing intensity and tilling activities). The site-specific nature of the found relations suggests that extension of findings in response to changes in land use in montane Andean ecosystems is risky; therefore, future evaluations of the impact of land use change on soil parameters should take into consideration that responses are or can be site specific.

El síncope asociado con el ejercicio es una condición que debe alertar al médico tratante; en primera instancia, se descartan alteraciones estructurales cardiacas que predispongan a muerte súbita, y en segundo lugar se evalúa la presencia de arritmias que potencialmente causen esta condición. En pacientes mayores de 35 años se descartan la enfermedad coronaria y las valvulopatías como eventuales causas. En sujetos que entrenan de manera frecuente, el tono vagal aumentado es una condición adaptativa común que a veces puede causar síncope cardioinhibitorio asociado con el ejercicio, cuya presentación puede variar desde bradiarritmias hasta asistolia, por lo cual constituye un reto diagnóstico.Exercise-induced syncope is a condition that should alert the treating physician; structural cardiac abnormalities that predispose to sudden death should be discarded, and the presence of arrhythmias that may potentially cause this condition are evaluated. In patients over 35 years, coronary and valvular disease are ruled-out as a possible cause of syncope associated with exercise. In subjects who train frequently, increased vagal tone is a common adaptive condition that may sometimes cause cardio-inhibitory syncope associated with exercise, whose presentation may vary from bradyarrhythmia to asystolia, thereby providing a diagnostic challenge.