35 research outputs found
Defining the DESI Bright Galaxy Survey target selection
This thesis aims to cover the steps taken for the selection of the input galaxy catalogue for the Dark Energy Spectroscopic Instrument (DESI) Bright Galaxy Survey (BGS) using the photometric Legacy Surveys. The BGS is a redshift survey of bright galaxies that will be performed using the DESI 5,000 fibre spectrograph on the 4m Mayall telescope in at Kitt Peak, Arizona. Our galaxy selection implements a new way to perform star galaxy separation using the Gaia photometry. The purity of our sample is assessed with previous galaxy surveys GAMA and the SDSS Main Galaxy Sample, and with the MXXL light-cone mock catalogue through clustering measurements. The robustness of the BGS selection criteria are assessed by quantifying the dependence of the target galaxy density on imaging and other properties. Systematic correlations are found with amplitudes of less than 5 per cent. This work also presents the first results from the Survey Validation (SV) stage of DESI. Using the SV data we were able to assess our BGS selection and tune it to achieve a high redshift success rate. The final catalogue includes nearly 30 Million galaxies for a 14,000 deg2 area that covers the North and South Galactic Caps
Hydrodynamic Analysis on a Photocatalytic Reactor Using ANSYS Fluent<sup>®</sup>
Solar technology includes a wide variety of developments in environmental applications that include photovoltaic cells and photocatalytic devices, among others. Sunlight usage as a clean energy source is highly desirable in technology applications. The main interest of this proposal is to carry on with hydrodynamic analysis in photocatalytic reactors applications where sunlight is used to activate a chemical reaction to degrade water pollutants and calculations are based in computational fluid dynamics (CFD) using ANSYS®. The different steps, geometric domain, preprocessing steps, setup, and postprocessing steps, are described to display an analysis of a numerical calculation during the design of a photocatalytic reactor using the commercial software ANSYS Fluent®. This work may help as a guide for chemical reactor design and includes a numerical solution of one case for a photocatalytic reactor during its design process. In addition, simplifications are explained which enable the designer to make an efficient process of the numerical calculation. Calculations and analysis are carried over in ANSYS Fluent® a powerful multi-physics program suite to develop photocatalytic reactors
Characterizing the target selection pipeline for the Dark Energy Spectroscopic Instrument Bright Galaxy Survey
We present the steps taken to produce a reliable and complete input galaxy catalogue for the Dark Energy Spectroscopic Instrument (DESI) Bright Galaxy Survey (BGS) using the photometric Legacy Survey DR8 DECam. We analyse some of the main issues faced in the selection of targets for the DESI BGS, such as star–galaxy separation, contamination by fragmented stars and bright galaxies. Our pipeline utilizes a new way to select BGS galaxies using Gaia photometry and we implement geometrical and photometric masks that reduce the number of spurious objects. The resulting catalogue is cross-matched with the Galaxy And Mass Assembly (GAMA) survey to assess the completeness of the galaxy catalogue and the performance of the target selection. We also validate the clustering of the sources in our BGS catalogue by comparing with mock catalogues and the Sloan Digital Sky Survey (SDSS) data. Finally, the robustness of the BGS selection criteria is assessed by quantifying the dependence of the target galaxy density on imaging and other properties. The largest systematic correlation we find is a 7 per cent suppression of the target density in regions of high stellar density
The DESI Bright Galaxy Survey: Final Target Selection, Design, and Validation
Over the next 5 yr, the Dark Energy Spectroscopic Instrument (DESI) will use 10 spectrographs with 5000 fibers on the 4 m Mayall Telescope at Kitt Peak National Observatory to conduct the first Stage IV dark energy galaxy survey. At z 10 million galaxies spanning 14,000 deg2 . In this work, we present and validate the final BGS target selection and survey design. From the Legacy Surveys, BGS will target an r 80% fiber assignment efficiency. Finally, BGS Bright and BGS Faint will achieve >95% redshift success over any observing condition. BGS meets the requirements for an extensive range of scientific applications. BGS will yield the most precise baryon acoustic oscillation and redshift-space distortion measurements at z < 0.4. It presents opportunities for new methods that require highly complete and dense samples (e.g., N-point statistics, multitracers). BGS further provides a powerful tool to study galaxy populations and the relations between galaxies and dark matter
An overview of the utilisation of microalgae biomass derived from nutrient recycling of wet market wastewater and slaughterhouse wastewater
Microalgae have high nutritional values for aquatic organisms compared to fish meal, because microalgae cells are rich in proteins, lipids, and carbohydrates. However, the high cost for the commercial production of microalgae biomass using fresh water or artificial media limits its use as fish feed. Few studies have investigated the potential of wet market wastewater and slaughterhouse wastewater for the production of microalgae biomass. Hence, this study aims to highlight the potential of these types of wastewater as an alternative superior medium for microalgae biomass as they contain high levels of nutrients required for microalgae growth. This paper focuses on the benefits of microalgae biomass produced during the phycore-mediation of wet market wastewater and slaughterhouse wastewater as fish feed. The extraction techniques for lipids and proteins as well as the studies conducted on the use of microalgae biomass as fish feed were reviewed. The results showed that microalgae biomass can be used as fish feed due to feed utilisation efficiency, physiological activity, increased resistance for several diseases, improved stress response, and improved protein retention
Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials
Aims:
The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials.
Methods and Results:
Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594).
Conclusions:
GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation
Characterizing the target selection pipeline for the Dark Energy Spectroscopic Instrument Bright Galaxy Survey
Incidencia de la tecnología como herramienta pedagógica para facilitar el aprendizaje de las matemáticas
The importance of technology as a pedagogical tool to facilitate the learning of mathematics through the design of strategies and the execution of seminar workshops for teachers and legal representatives. The purpose is to incorporate ICT tools (Information and Communication Technologies) in the teacher's work in order to provide students with the knowledge, skills and procedures necessary to develop them in the didactic guide of the educational institution. The contents of the workshops are broken down sequentially and schematically, in which the content of a didactic guide will be socialized, where the use of tools available on the web for the teaching-learning process of mathematics is disclosed, each one of these These tools allow students to motivate themselves and innovate educational teaching in the new millennium and, in turn, take advantage of these potentialities, allowing them to promote collaborative work in the network of exchanges of ideas, experiences through the appropriate use of technology in the math subject. Educational technology is designed to help educators plan and control the learning process more efficiently, this being possible thanks to the use of resources such as smartphones, computers, televisions, among others. The development of these techniques has been established for decades to optimize the presentation and understanding of educational content to students.La importancia de la tecnología como herramienta pedagógica para facilitar el aprendizaje de las matemáticas por medio del diseño de estrategias y ejecución de seminarios talleres para docentes y representantes legales. El propósito radica en incorporar herramientas TIC (Tecnologías de la Información y la Comunicación) en la labor del docente con la finalidad de dotar a los estudiantes los conocimientos, habilidades y procedimientos necesarios para desarrollarlos en la guía didáctica de la institución educativa. Se desglosan de manera secuencial y esquemática los contenidos de los talleres en las cuales se socializará el contenido de una guía didáctica en donde se da a conocer el uso de herramientas disponibles en la web para el proceso enseñanza aprendizaje de las matemáticas, cada una de estas herramientas dan paso a que los alumnos/as se motiven e innoven la enseñanza educativa en el nuevo milenio y a su vez aprovechen estas potencialidades, permitiendo fomentar el trabajo colaborativo en la red de intercambios de ideas, experiencias mediante el uso adecuado de la tecnología en la asignatura de matemáticas. La tecnología educativa está diseñada para ayudar a los educadores a planificar y controlar el proceso de aprendizaje de manera más eficiente, siendo esto posible gracias al uso de recursos como teléfonos inteligentes, computadoras, televisores, entre otros. El desarrollo de estas técnicas se ha establecido durante décadas para optimizar la presentación y comprensión del contenido educativo a los estudiantes
Preliminary clustering properties of the DESI BGS bright targets using DR9 Legacy Imaging Surveys
We characterize the selection cuts and clustering properties of a magnitude-limited sample of bright galaxies that is part of the Bright Galaxy Survey (BGS) of the Dark Energy Spectroscopic Instrument (DESI) using the ninth data release of the Legacy Imaging Surveys (DR9). We describe changes in the DR9 selection compared to the DR8 one and we also compare the DR9 selection in three distinct regions: BASS/MzLS in the north Galactic Cap (NGC), DECaLS in the NGC, and DECaLS in the south Galactic Cap (SGC). We investigate the systematics associated with the selection and assess its completeness by matching the BGS targets with the Galaxy and Mass Assembly (GAMA) survey. We measure the angular clustering for the overall bright sample (rmag ≤ 19.5) and as function of apparent magnitude and colour. This enables to determine the clustering strength r0 and slope γ by fitting a power-law model that can be used to generate accurate mock catalogues for this tracer. We use a counts-in-cells technique to explore higher order statistics and cross-correlations with external spectroscopic data sets in order to check the evolution of the clustering with redshift and the redshift distribution of the BGS targets using clustering redshifts. While this work validates the properties of the BGS bright targets, the final target selection pipeline and clustering properties of the entire DESI BGS will be fully characterized and validated with the spectroscopic data of Survey Validation