First observations and magnitude measurement of Starlink's Darksat

Measure the Sloan g' magnitudes of the Starlink's STARLINK-1130 (Darksat) and 1113 LEO communication satellites and determine the effectiveness of the Darksat darkening treatment at 475.4\,nm. Two observations of the Starlink's Darksat LEO communication satellite were conducted on 2020/02/08 and 2020/03/06 using a Sloan r' and g' filter respectively. While a second satellite, STARLINK-1113 was observed on 2020/03/06 using a Sloan g' filter. The initial observation on 2020/02/08 was a test observation when Darksat was still manoeuvring to its nominal orbit and orientation. Based on the successful test observation, the first main observation was conducted on 2020/03/06 along with an observation of the second Starlink satellite. The calibration, image processing and analysis of the Darksat Sloan g' image gives an estimated Sloan g' magnitude of $7.46\pm0.04$ at a range of 976.50\,km. For STARLINK-1113 an estimated Sloan g' magnitude of $6.59\pm0.05$ at a range of 941.62\,km was found. When scaled to a range of 550\,km and corrected for the solar and observer phase angles, a reduction by a factor of two is seen in the reflected solar flux between Darksat and STARLINK-1113. The data and results presented in this work, show that the special darkening coating used by Starlink for Darksat has darkened the Sloan g' magnitude by $0.77\pm0.05$\,mag, when the range is equal to a nominal orbital height (550\,km). This result will serve members of the astronomical community modelling the satellite mega-constellations, to ascertain their true impact on both the amateur and professional astronomical communities. Concurrent and further observations are planned to cover the full optical and NIR spectrum, from an ensemble of instruments, telescopes and observatories.Comment: Accepted for publication in A&A Letters. 5 pages, 2 figures and 4 table

Children’s narratives on migrant refugees: a practice of global citizenship

Globalisation has brought about great social and economic impact, as well as great challenges. Major developments have taken place in the mobility of capital and, to a lesser extent, of goods; not so in the mobility of people seeking asylum due to persecution and war. This article approaches the phenomenon of migration, particularly of refugees, as learning content for early childhood. The research is presented from a qualitative approach based on the results of a project on this topic implemented in a rural school in Spain. The results of the data analysis reveal that children attribute external reasons, of survival, to the refugees’ forced departure from their country of origin. The children’s imaginary reproduces the social construction of adults on the status and situation of refugees, and they also show a critical attitude towards the violation of human rights and the abuse of fellow children. Finally, respect, cultural empathy and social commitment in the face of injustice are presented as fundamental values for education in global citizenship from the earliest stages of schooling

Multi-Phase Flash Sintering: The Next Natural Step in Flash Sintering Evolution

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Análisis de la distribución de hidrógeno en contención y pozo seco de C.N. Cofrentes.

El desarrollo del modelo de la Contención de C.N. Cofrentes mediante GOTHIC se ha llevado a cabo introduciendo todos los datos geométricos y de estructuras de la Contención, pudiendo así modelar todos los recintos interiores y habitaciones que la componen. De esta forma se ha obtenido un modelo 3D detallado y con la precisión suficiente para el estudio global de la gestión del hidrógeno, permitiendo tener en cuenta, a la hora de la distribución del hidrógeno, la asimetría tanto de la contención como de las descargas de masa y en energía que en ella se realizan, permitiendo simular la distribución del vapor y el hidrógeno presentes en el accidente severo para poder determinar las zonas de mayor riesgo de deflagración o detonación durante la evolución del accident

Genetic inbreeding depression load for fertility traits in Pura Raza Española mares

Fertility is a key factor in the economic success of horse farms. However, it has received little attention due to the difficulty of measuring fertility objectively. Since its studbook creation (1912), the Pura Raza Española (PRE) breed has been a closed population and become high in-bred resulting in inbreeding depression (poor phenotypic values). Nevertheless, heterogeneous effects of inbreeding depression have been detected among founders and nonfounders. The aims of this study were (1) to analyze the genetic parameters for reproductive traits in mares of the PRE horse breed and (2) to estimate, for the first time, the inbreeding depression load associated with common ancestors of the breed. A total of 22, 799 mares were analyzed. Heritability estimates ranged from 0.05 (interval between first and second foaling) to 0.16 (age at first foaling), whereas inbreeding depression load ratios ranged from 0.06 (parturition efficiency at 6th foaling) to 0.17 (age at first foaling), for a partial inbreeding coefficient of 10%. Although heritability is related to the variability expressed in the population, inbreeding depression load ratios measure the potential variability, whether expressed in the population or not. Most correlations between additive and inbreeding depression load genetic values were significant (P < 0.001) and of low to moderate magnitude. Our results confirm that individual inbreeding depression loads allow us to select horses that have a genetic value resistant to the deleterious effects of inbreeding. © The Author(s) 2021. Published by Oxford University Press on behalf of the American Society of Animal Science

Influencia de acondicionadores sintéticos y orgánicos en cuatro suelos del valle del cauca

A cuatro tipos de suelos con problemas de compactación – Fluventic haplustoll (1), Pachic haplustoll (2), Typic pellustert (3) y Petrocalcic natrustalf (4) - se les aplicaron Potasium propenoate, dos dosis del producto en seco y dos dosis en líquido, cachaza y gallinaza. La planta indicadora fue la soya P-32. El experimento se diseñó completamente al azar, con nueve tratamientos y tres replicaciones. En área foliar y producción de materia seca total, mostraron diferencias significativas los tratamientos con acondicionador sin rético en forma líquida en el suelo 1; las 2 dosis del acondicionador sintético en forma sólida lo mismo que la gallinaza mostraron diferencias significativas en los suelos 2 y 3. Se encontraron diferencias significativas para los tratamientos con acondicionador sintético en espacio aéreo para los suelos 1,2 Y 3; en densidad aparente en seco yen húmedo yen resistencia al penetrómetro para el suelo 2. Los análisis químicos del suelo realizados al finalizar el experimento mostraron niveles inadecuados en elementos mayores y menores, excepto boro, en los suelos 1, 2 y 3.The purpose of this work was to investigate the effect of one synthetic soil conditioner (potassium propenoate) and two kinds of organic products (sugar Mill factory residue and poultry manure) in the physical properties of soils with compactación problems of the Cauca Valley. Four types of soils were utilized: fluventic haplustoll (1), Pachic haplustoll (2), Typic pellustert (3), and Petrocalcic natrustalf (4). Soybean P-32 was indicator plant, utilizing a completely randomized block design with nine treatments and three replications. The leaf area and yield of total dry matter were significatively better with syntetic conditioner in liquid form for soil L; the soil conditioner applied in solid form and the poultry manure were of significant levels for soils 2 and 3. Significant differences were found in favor of the synthetic conditioner for the air space variable in soils (1), (2) and (3); for the bulk density, measured in dry and wet states, and the penetrometer resistance variables for soil (2). Soil chemical analysis showed adequate levels for plant growth in soils 1, 2,3 for major and minor elements, except for boron

Reactive Flash Sintering

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