14 research outputs found

    CaracterizaciĂłn de la emisiĂłn de microondas en M31 usando nuevos datos del Sardinia Radio Telescope

    Get PDF
    In this study, we have performed the correlation analysis between the microwaves maps and both, the far - mid infrared maps and the parameters maps in the Andromeda galaxy. For this aim, we have used intensity maps from the Sardinia Radio Telescope and public data from both the Herschel Space Observatory and Spitzer Space Telescope. The parameters maps used were created by combining public data and models produced by DustEM. There are four sections: the introduction, the methodology, the results and the conclusions. In the first section, it’s established the basic knowledge. We have begun by explaining what interstellar medium (ISM) is as well as the phenomena that take place in its inner. Those include: the temperature, composition and relative abundance for different dust grain types which are found in the medium. Next, we present various emission mechanisms focusing on the anomalous microwave emission. Later on, we gather up and display information about the Andromeda galaxy, explaining its suitability to be our object of study, justifying the reason for us to choose it over other galaxies. In the second one, we have explained the basic characteristics of the radio telescope that we have used for the C-band and K-band observations. This is followed by the observation, planning and measurement strategies of the calibration sources. Then, we have described the treatment carried out on the observations, as well as the models obtained through DustEM and the archive maps that we have selected. In the last part of this sextion we have detailed in depth the process to adjust the archive maps to our microwave maps. To close this section, we have added an explanation on how the correlations between maps have been made, as well as the procedure followed using both the DustEM and the infrared maps in order to obtain the parameter maps. In the third section - which can be divided into two smaller blocks - the results of this study are presented. We have started the first one by finding out the correlation which exists between both microwave and infrared maps. This has been done having the adjusted maps as references. We have obtained, in most of the results of the correlations, values of the Pearson’s coefficient around 0.6 (for the ring’s region), 0.4 (for the disc’s area) and 0.2 (for the nucleus). However, for the nucleus we have got other values in the maps of 24 and 100 m, for which the values have been around 0.7. In the second one, the correlation between the SRT and both the BG and ISRF map have shown values for the coefficient of Pearson around 0.7 in the ring and 0.5 in the disc. For the nucleus in the ISRF, the value has been of 0.7 (being the same as it was for the ring), but the nucleus hasn’t show any correlation with the BG. For the VSG map we have found a correlation of around 0.4 with the disc. Finally, in the fourth and last section, we have resolved that the correlation between the SRT and parameters maps indicate that the emission of microwaves is mainly related with the intensity of the radiation field, with the abundance of BG and with the dust’s temperature. Regarding the relation between the abundance of VSG and the microwave emission, it has only been noticed in the disc. This results are coherent with the ones obtained in the work of Tibbs et al. (2012). On the other hand, the results for the dust’s species haven’t been conclusive, due to the results may have been affected by diverse factors. Therefore, it’s concluded that, for improving the outcomes, it would be required that we rose the range of values (used for the dust’s species), used another adjustment technique or a more accurate and precise model.En este trabajo se ha realizado el anÂŽalisis de la correlaciÂŽon entre mapas de microondas combinados con mapas de archivo para infrarrojo lejano y medio, y mapas de parÂŽametros para la galaxia de AndrÂŽomeda. Se han usado mapas en intensidad procedentes del Sardinia Radio Telescope y datos pÂŽublicos procedentes de Herschel Space Observatory y Spitzer Space Telescope. Los mapas de parÂŽametros usados se han creado a partir de la informaciÂŽon obtenida al combinar los mapas de archivo y con los modelos generados por el cÂŽodigo DustEM. En la primera secciÂŽon se establece los conocimientos bÂŽasicos. Comenzamos explicando en quÂŽe consiste el medio interestelar (ISM de sus siglas en inglÂŽes) asŽı como los fenÂŽomenos que se manifiestan en su interior, la diversidad de medios que encontramos asociados a unos valores de temperatura determinados y composiciÂŽon, o las abundancias de distintas especies de polvo. Luego presentamos los diversos mecanismos de emisiÂŽon presentes en el ISM centrÂŽandonos en los mecanismos de emisiÂŽon propuestos para explicar la emisiÂŽon anÂŽomala de microondas (AME de sus siglas en inglÂŽes). A continuaciÂŽon exponemos informaciÂŽon sobre la galaxia de AndrÂŽomeda explicando la idoneidad para ser nuestro objeto de estudio. En la segunda secciÂŽon, explicamos las caracterŽısticas bÂŽasicas el radiotelescopio que usamos para las observaciones en banda C y banda K, seguido de las estrategia de observaciÂŽon, planificaciÂŽon y mediciÂŽon de las fuentes de calibraciÂŽon. Luego, hablaremos sobre el tratamiento realizado sobre las observaciones asŽı como los mapas de archivo que hemos seleccionado y sobre el DustEM. En la ÂŽultima parte de este capŽıtulo detallaremos con profundidad el proceso para ajustar los mapas de archivo a los mapas en microondas. Para cerrar este capŽıtulo, se explicarÂŽa cÂŽomo se han realizado las correlaciones entre mapas y el procedimiento seguido empleando DustEM y los mapas en el infrarrojo para obtener los mapas de parÂŽametros. En la tercer secciÂŽon, se presentan los resultados de este estudio. Partiendo de mapas ajustados, comenzaremos la primera parte del capŽıtulo estimando la correlaciÂŽon entre los mapas en microondas y los mapas en infrarrojo. Obteniendo en la mayorŽıa de las correlaciones valores del coeficiente de Pearson en torno a 0.6 para la regiÂŽon de anillo, sobre 0.4 para la regiÂŽon de disco y valores en torno a 0.2 para el nÂŽucleo, excepto para los mapas de 24 y 100 m. En la segunda parte de esta secciÂŽon, la correlaciÂŽon de los mapas de SRT con el mapa de BG y ISRF muestran valores del coeficiente de Pearson en torno a 0.7 en regiones como el anillo y el nÂŽucleo, excepto BG que no muestra correlaciÂŽon con el nÂŽucleo, y 0.5 en el disco. Para el mapa de VSG encontramos una correlaciÂŽon en torno a 0.4 con el disco. Finalmente, en la cuarta secciÂŽon, se concluye que la correlaciÂŽon entre los mapas de SRT y los mapas de parÂŽametros indican que la emisiÂŽon de microondas se relaciona principalmente con la intensidad del campo de radiaciÂŽon, con la abundancia de BG y con la temperatura del polvo. Respecto a la relaciÂŽon entre la abundancia de VSG y la emisiÂŽon en microondas sÂŽolo es observada en el disco. Estos resultados son coherentes con los obtenidos en Tibbs et al. (2012). En cambio, los resultados para las especies de polvo no son concluyentes debido a diversos factores que han podido perjudicar los resultados. Por lo tanto se concluye que para mejorar los resultados se debe usar un modelo mÂŽas preciso, aumentar el rango de valores usados para las especies de polvo o usar otra tÂŽecnica de ajuste

    Alpha and beta phylogenetic diversities jointly reveal ant community assembly mechanisms along a tropical elevational gradient

    Get PDF
    Despite the long-standing interest in the organization of ant communities across elevational gradients, few studies have incorporated the evolutionary information to understand the historical processes that underlay such patterns. Through the evaluation of phylogenetic α and ÎČ-diversity, we analyzed the structure of leaf-litter ant communities along the Cofre de Perote mountain in Mexico and evaluated whether deterministic- (i.e., habitat filtering, interspecific competition) or stochastic-driven processes (i.e., dispersal limitation) were driving the observed patterns. Lowland and some highland sites showed phylogenetic clustering, whereas intermediate elevations and the highest site presented phylogenetic overdispersion. We infer that strong environmental constraints found at the bottom and the top elevations are favoring closely-related species to prevail at those elevations. Conversely, less stressful climatic conditions at intermediate elevations suggest interspecific interactions are more important in these environments. Total phylogenetic dissimilarity was driven by the turnover component, indicating that the turnover of ant species along the mountain is actually shifts of lineages adapted to particular locations resembling their ancestral niche. The greater phylogenetic dissimilarity between communities was related to greater temperature differences probably due to narrow thermal tolerances inherent to several ant lineages that evolved in more stable conditions. Our results suggest that the interplay between environmental filtering, interspecific competition and habitat specialization plays an important role in the assembly of leaf-litter ant communities along elevational gradients

    DesinfecciĂłn de conductos radiculares: opciones al hipoclorito de sodio y a la clorhexidina

    Get PDF
    Introduction: the use of irrigants for intraoral disinfection is indispensable for eliminating the bacterial load of the pathology present in the dental piece.Objective: to discuss the efficacy of intra-canal irrigants such as MTAD, Tetraclean and Catremida.Methods: bibliographic review based on the use of scientific search engines between 2018 and 2023. The search was carried out in the research databases: Pubmed, Scielo. The words used within the literature search were “irrigation and endodontics”, “irrigants in endodontics”, “new endodontic irrigants”. The research was limited to the English and Spanish language, and only articles that talked about current irrigant solutions used in Endodontics were included. Development: MTAD, Tetraclean and Cetrimide have the ability for smear removal, there are also promising data considering the antimicrobial activity of MTAD, especially against E. faecalis and its effect on dental stem cells in regenerative endodontics, although they are still controversial. Despite some unfavorable reactions and havoc that has been generated in the tissues of patients by the use of NaOCl, for years this irrigant continues to be the most suitable for dental practice.Conclusions: none of the substances used individually meet the requirements of an ideal irrigant, therefore it has been found feasible to combine irrigants together with the proper instrumentation of the root canal to have a much greater impact on the outcome of endodontic treatment. IntroducciĂłn: el uso de irrigantes para la desinfecciĂłn intraconducto es indispensable para eliminar la carga bacteriana de la patologĂ­a presente en la pieza dental.Objetivo: argumentar sobre la eficacia de irrigantes intraconducto como MTAD, Tetraclean y Catremida.MĂ©todos: revisiĂłn bibliogrĂĄfica a partir del uso de buscadores cientĂ­ficos entre el año 2018 y 2023. La bĂșsqueda se llevĂł cabo en las bases de datos de investigaciĂłn: Pubmed, Scielo. Las palabras utilizadas dentro de la bĂșsqueda de la literatura fueron “irrigaciĂłn y endodoncia”, “irrigantes en endodoncia”, “nuevos irrigantes endodĂłnticos”. La investigaciĂłn se limitĂł al idioma inglĂ©s y al español, y solo se incluyeron los artĂ­culos que hablaban sobre las soluciones irrigantes actuales usados en Endodoncia.  Desarrollo: el MTAD, Tetraclean y Cetrimida tienen la capacidad para la eliminaciĂłn del barrillo dentinario, tambiĂ©n existen datos prometedores que consideran la actividad antimicrobiana de MTAD, especialmente contra E. faecalis y su efecto sobre las cĂ©lulas madre dentales en la endodoncia regenerativa, aunque todavĂ­a son motivo de controversia. A pesar de algunas reacciones y estragos desfavorables que se ha generado en los tejidos de los pacientes por la utilizaciĂłn del NaOCl, para la prĂĄctica odontolĂłgica por años este irrigante continĂșa siendo el mĂĄs adecuado.Conclusiones: ninguna de las sustancias utilizada individualmente cumple con los requisitos de un irrigante ideal, debido a esto se ha visto factible la combinaciĂłn de irrigantes junto con la instrumentaciĂłn adecuada del conducto radicular para tener un impacto mucho mayor en el resultado del tratamiento endodĂłntico

    Apophis planetary defense campaign

    Get PDF
    We describe results of a planetary defense exercise conducted during the close approach to Earth by the near-Earth asteroid (99942) Apophis during 2020 December–2021 March. The planetary defense community has been conducting observational campaigns since 2017 to test the operational readiness of the global planetary defense capabilities. These community-led global exercises were carried out with the support of NASA's Planetary Defense Coordination Office and the International Asteroid Warning Network. The Apophis campaign is the third in our series of planetary defense exercises. The goal of this campaign was to recover, track, and characterize Apophis as a potential impactor to exercise the planetary defense system including observations, hypothetical risk assessment and risk prediction, and hazard communication. Based on the campaign results, we present lessons learned about our ability to observe and model a potential impactor. Data products derived from astrometric observations were available for inclusion in our risk assessment model almost immediately, allowing real-time updates to the impact probability calculation and possible impact locations. An early NEOWISE diameter measurement provided a significant improvement in the uncertainty on the range of hypothetical impact outcomes. The availability of different characterization methods such as photometry, spectroscopy, and radar provided robustness to our ability to assess the potential impact risk

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Mexico ants: incidence and abundance along the Nearctic–Neotropical interface

    No full text
    International audienceto explore different aspects of the population and community research of ants at different spatial scales, and to aid in the establishment of conservation policies and actions. There are no copyright restrictions. Please cite this data paper when using its data for publications or teaching events

    Mexico's Ants: Who are They and Where do They Live?

    No full text
    International audienc
    corecore