160 research outputs found

    Secondary traits related to kernel setting in transgenic maize hybrids at low and high plant densities and their potential use in breeding programs

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    Maize (Zea mays. L) traditional breeding presents limitations when selection is performed by adaptation to suboptimalconditions. One strategy to achieve greater efficiency in these environments is to include measurements ofsecondary traits related to the main grain yield component, i.e. kernel number per plant (KNP), which is associatedto other three secondary traits: plant growth rate during the critical period (PGRcp) for kernel setting, biomasspartitioning index to the ear during this period (PIcp) and the efficiency of the ear to set kernels or reproductiveefficiency (RE). Phenotypic variations in these KNP related traits were evaluated considering: i) plant densities,and ii) simple and staked transgenic maize hybrids. The objective of this study was to identify the contribution ofthese secondary traits to KNP in six modern single-cross transgenic hybrids: the simple and staked transgenic versionsof DK747 and DK190 (Bt: 747MG and 190MG; RR: 747RR and 190RR; and Bt-RR: 747MGRR and 190MGRR)cultivated at low and high plant densities. For this purpose, KNP and secondary traits were recorded at the individualplant level and the data set was analyzed using multivariate analysis techniques. At low plant density, PGRcpwas the critical trait for kernel setting in all hybrids but PIcp or RE also contributed to KNP of the DK747 groupand the D190 group, respectively. At high plant density, a differential contribution of secondary traits to KNP wasrecorded among hybrids. For DK747MG and DK190MG, RE mainly determined KNP, but for the DK747RR andDK747MGRR higher PIcp had a positive impact on KNP. These results highlight the importance of including secondarytraits associated to KNP in breeding programs

    Optimus: plataforma digital dedicada a la recomendaci?n y gesti?n de recolocaci?n de servicios de telefon?a m?vil pospago

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    En Lima Metropolitana, los clientes de telefon?a m?vil pospago no hacen uso de todos los beneficios adquiridos mediante contrato con las empresas operadoras, adem?s de verse envueltos en gestiones complejas para realizar solicitudes de recolocaci?n. Por ello, se identific? una oportunidad para implementar la plataforma digital B2C denominada Optimus, que permita evaluar sus necesidades, comparar la oferta comercial existente, recomendar la mejor opci?n de plan y gestionar su recolocaci?n. Para tal efecto, se plante? como objetivo determinar la factibilidad econ?mica y t?cnica del modelo de negocio, considerando dos fases estrat?gicas: la primera, de penetraci?n, con el objetivo de incrementar la cuota de mercado; y la segunda, de posicionamiento basado en liderazgo de costos. Realizada la investigaci?n de mercado, los resultados se?alaron que el 43% de las personas que conforman el mercado potencial estar?an dispuestas a pagar por los servicios de Optimus, con un ticket m?ximo de S/80,00. Finalmente, se evalu? la viabilidad econ?mica tomando en cuenta los escenarios pesimista, esperado y optimista, circunscritos a las variables de ingresos (precio, cantidad y volumen) y a diversos costos, en especial el de autorizaci?n de representatividad legal (carta poder), que genera gran impacto en el costo de ventas

    Understanding The Correlation Of Libs And Acoustic Measurements Of Rocks And Soils Found In The Traverse Of The Perseverance Rover Across The Jezero Crater, Mars

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    The SuperCam instrument of the NASA MARS 2020 Perseverance rover combines a suite of atomic and molecular spectroscopies intended for an extensive description of rocks, soils and minerals in the surroundings of the landing site of the mission – the Jezero crater. The microphone installed on the SuperCam instrument allows the acquisition of acoustic signals resulting from the expansion of laser-induced plasmas towards the atmosphere. Apart from being affected by the propagation characteristics of the Mars atmosphere, the acoustic signal has an additional component related to the properties of the target including surface morphology, hardness, deformation parameters, and elasticity, among others. This information is currently being investigated as a complementary resource for characterization of the ablated material and may well supplement the LIBS data gathered from coincident laser shots. This talk will present SuperCam acoustic data of rocks and minerals found in the traverse of the Perseverance rover and will discuss its correlation with LIBS spectra.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    LIBS and Acoustic Measurements of Rocks and Regolith Found in the Traverse of the Perseverance Rover Across the Jezero Crater, Mars

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    The SuperCam instrument of the NASA MARS 2020 Perseverance rover combines a suite of atomic and molecular spectroscopies intended for an extensive description of rocks, soils and minerals in the surroundings of the landing site of the mission – the Jezero crater. The microphone installed on the SuperCam instrument allows the acquisition of acoustic signals resulting from the expansion of laser-induced plasmas towards the atmosphere. Apart from being affected by the propagation characteristics of the Mars atmosphere, the acoustic signal has an additional component related to the properties of the target including surface morphology, hardness, deformation parameters, and elasticity, among others. This information is currently being investigated as a complementary resource for characterization of the ablated material and may well supplement the LIBS data gathered from coincident laser shots. This talk will present SuperCam acoustic data of rocks and minerals found in the traverse of the Perseverance rover and will discuss its correlation with LIBS spectra.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    The sound of geological targets on Mars from the absolute intensity of laser-induced sparks shock waves

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    Inspection of geological material is one of the main goals of the Perseverance rover during its journey across the landscape of the Jezero crater in Mars. NASA's rover integrates SuperCam, an instrument capable of performing standoff characterization of samples using a variety of techniques. Among those tools, SuperCam can perform laser-induced breakdown spectroscopy (LIBS) studies to elucidate the chemical composition of the targets of interest. Data from optical spectroscopy can be supplemented by simultaneously-produced laser-produced plasma acoustics in order to expand the information acquired from the probed rocks thanks to the SuperCam's microphone (MIC) as it can be synchronized with the LIBS laser. Herein, we report cover results from LIBS and MIC during Perseverance's first 380 sols on the Martian surface. We study the correlation between both recorded signals, considering the main intrasample and environmental sources of variation for each technique, to understand their behavior and how they can be interpreted together towards complimenting LIBS with acoustics. We find that louder and more stable acoustic signals are recorded from rock with compact surfaces, i.e., low presence loose particulate material, and harder mineral phases in their composition. Reported results constitute the first description of the evolution of the intensity in the time domain of shockwaves from laser-produced plasmas on geological targets recorded in Mars. These signals are expected contain physicochemical signatures pertaining to the inspected sampling positions. As the dependence of the acoustic signal recorded on the sample composition, provided by LIBS, is unveiled, the sound from sparks become a powerful tool for the identification of mineral phases with similar optical emission spectra.Many people helped with this project in addition to the co-authors, including hardware and operation teams, and we are most grateful for their support. This project was supported in the USA by NASA’s Mars Exploration Program and in France is conducted under the authority of CNES. Research funded by projects UMA18-FEDERJA-272 from Junta de AndalucĂ­a and PID2020-119185GB-I00 from Ministerio de Ciencia e Innovacion, of Spain. P.P. is grateful to the European Union’s Next Generation EU (NGEU) plan and the Spanish Ministerio de Universidades for his Margarita Salas fellowship under the program â€Čâ€ČAyudas para la Recualificacion del Sistema Universitario Españolâ€Čâ€Č. RCW was funded by JPL contract 1681089. A.U was funded by NASA Mars 2020 Participating Scientist program 80NSSC21K0330. Funding for open access charge: Universidad de MĂĄlaga / CBU

    The political economy of progressive fiscal contracts in Africa and Latin America

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    Motivation How can poorer developing countries escape from the vicious circle in which, because the state is fragile, those countries cannot raise sufficient public revenue to be able to finance development, leading to the persistence of poverty and state fragility? We explore a new approach to this problem, which we call progressive fiscal contracts, in which government earmarks the proceeds of particular taxes to be spent on forms of expenditure which will have widespread benefits for lower income groups, such as health, education and social protection. Taxpayers are thus offered a contractual relationship with government (better‐targeted delivery of public services in return for tax payments) in place of a coercive one (simply being ordered to pay taxes, with nothing being offered in exchange). We seek to examine whether this kind of contractual approach offers a way forward for developing countries. Purpose Across five countries (Bolivia, Ecuador, Venezuela, Ghana and Zambia) between 2000 and 2015, we seek to find out whether tax yields have improved following the introduction of progressive fiscal contracts, whether conflict and poverty have declined, and whether there have been countervailing costs in terms of reduced efficiency. We also examine the experience of two countries (Brazil and Chile) where there is no formal ear‐marking but government has encouraged the public to think of particular taxes as being associated with particular forms of expenditure. Approach and methods We assess the impact of changes in tax yields, welfare indicators and conflict indicators by means of panel‐data regressions, tabular comparisons and, in Bolivia, qualitative interviews. Changes in efficiency are assessed through examination of changes in tax structure. Findings Across all of the countries surveyed, the introduction of progressive fiscal contracts has been associated with a reduction in headcount poverty between 2000 and 2015, and in Bolivia our qualitative evidence suggests that the relationship can be seen as a causal one. In three cases out of five (Ghana, Bolivia and Ecuador) tax yields have increased, and in two (Ecuador and Bolivia) there was a significant reduction in political violence. In the Latin American cases examined, but not the African ones, there was a shift from royalty‐based taxation to income‐based taxation of natural resources, suggesting the likelihood of an improvement in efficiency over the period in those countries only. In these cases, the stereotypical view that progressive fiscal contracts improve equity at the expense of efficiency is contradicted. Policy implications (or conclusions) ‘Progressive fiscal contracts’, which originated as a device for making tax payments more palatable by offering social benefits in return, show promise as an innovative strategy for boosting tax ratios, reducing political violence and reducing poverty, which deserves further exploration

    Toward an Open-Access Global Database for Mapping, Control, and Surveillance of Neglected Tropical Diseases

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    There is growing interest in the scientific community, health ministries, and other organizations to control and eventually eliminate neglected tropical diseases (NTDs). Control efforts require reliable maps of NTD distribution estimated from appropriate models and survey data on the number of infected people among those examined at a given location. This kind of data is often available in the literature as part of epidemiological studies. However, an open-access database compiling location-specific survey data does not yet exist. We address this problem through a systematic literature review, along with contacting ministries of health, and research institutions to obtain disease data, including details on diagnostic techniques, demographic characteristics of the surveyed individuals, and geographical coordinates. All data were entered into a database which is freely accessible via the Internet (http://www.gntd.org). In contrast to similar efforts of the Global Atlas of Helminth Infections (GAHI) project, the survey data are not only displayed in form of maps but all information can be browsed, based on different search criteria, and downloaded as Excel files for further analyses. At the beginning of 2011, the database included over 12,000 survey locations for schistosomiasis across Africa, and it is continuously updated to cover other NTDs globally

    The SuperCam Instrument Suite on the Mars 2020 Rover: Science Objectives and Mast-Unit Description

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    On the NASA 2020 rover mission to Jezero crater, the remote determination of the texture, mineralogy and chemistry of rocks is essential to quickly and thoroughly characterize an area and to optimize the selection of samples for return to Earth. As part of the Perseverance payload, SuperCam is a suite of five techniques that provide critical and complementary observations via Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman and Luminescence (TRR/L), visible and near-infrared spectroscopy (VISIR), high-resolution color imaging (RMI), and acoustic recording (MIC). SuperCam operates at remote distances, primarily 2-7 m, while providing data at sub-mm to mm scales. We report on SuperCam's science objectives in the context of the Mars 2020 mission goals and ways the different techniques can address these questions. The instrument is made up of three separate subsystems: the Mast Unit is designed and built in France; the Body Unit is provided by the United States; the calibration target holder is contributed by Spain, and the targets themselves by the entire science team. This publication focuses on the design, development, and tests of the Mast Unit; companion papers describe the other units. The goal of this work is to provide an understanding of the technical choices made, the constraints that were imposed, and ultimately the validated performance of the flight model as it leaves Earth, and it will serve as the foundation for Mars operations and future processing of the data.In France was provided by the Centre National d'Etudes Spatiales (CNES). Human resources were provided in part by the Centre National de la Recherche Scientifique (CNRS) and universities. Funding was provided in the US by NASA's Mars Exploration Program. Some funding of data analyses at Los Alamos National Laboratory (LANL) was provided by laboratory-directed research and development funds
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