13,013 research outputs found

    Conservation and use of genetic resources of underutilized crops in the Americas - A continental analysis

    Get PDF
    Latin America is home to dramatically diverse agroecological regions which harbor a high concentration of underutilized plant species, whose genetic resources hold the potential to address challenges such as sustainable agricultural development, food security and sovereignty, and climate change. This paper examines the status of an expert-informed list of underutilized crops in Latin America and analyses how the most common features of underuse apply to these. The analysis pays special attention to if and how existing international policy and legal frameworks on biodiversity and plant genetic resources effectively support or not the conservation and sustainable use of underutilized crops. Results show that not all minor crops are affected by the same degree of neglect, and that the aspects under which any crop is underutilized vary greatly, calling for specific analyses and interventions. We also show that current international policy and legal instruments have so far provided limited stimulus and funding for the conservation and sustainable use of the genetic resources of these crops. Finally, the paper proposes an analytical framework for identifying and evaluating a crop’s underutilization, in order to define the most appropriate type and levels of intervention (international, national, local) for improving its statu

    On the uniqueness of the helicoid and Enneper’s surface in the Lorentz-Minkowski space R31

    Get PDF
    In this paper we deal with the uniqueness of the Lorentzian helicoid and Enneper’s surface among properly embedded maximal surfaces with lightlike boundary of mirror symmetry in the Lorentz-Minkowski space R3Ministerio de Ciencia y Tecnología MTM2004-00160Ministerio de Ciencia y Tecnología MTM2007-61775Junta de Andalucía P06-FQM-01642Junta de Andalucía FQM32

    Business Cycle and Speculative Pressures in a Target Zone

    Get PDF
    In the past time, most economies have suffered cyclical fluctuations in their activity which may influence the optimal use of productive factors in long slow-growth phases or price stability in periods of fast growth. This paper focuses on the possible interrelationship between business cycles and exchange rate ‡uctuations. We have chosen the European Monetary System framework in the nineties, from June 1989 to December 1998, because the Peseta belonged to the EMS during that time. This sample is specially interesting because it includes the worst crisis of the System in 1992-93 and the following ones affecting emerging countries like Mexico, Brazil or Russia at the end of the decade. We use a Binary Dependent Variable Logit Model to estimate the readjustment probability inside a band for two currencies, the Peseta and the french Franc . We calculate the dependent variable values from a Markov-Switching Regime Model with constant transition probabilities. We prove that it is a suitable method and that it allows both real and monetary variables to be identified in order to explain speculative pressures.Readjustment Probability, Speculative Pressures, Economic Fluctuations.

    Harmonic mappings and conformal minimal immersions of Riemann surfaces into RN

    Get PDF
    We prove that for any open Riemann surface N, natural number N ≥ 3, non-constant harmonic map h:N→R N−2 and holomorphic 2-form H on N , there exists a weakly complete harmonic map X=(Xj)j=1,…,\scN:N→R\scN with Hopf differential H and (Xj)j=3,…,\scN=h. In particular, there exists a complete conformal minimal immersion Y=(Yj)j=1,…,\scN:N→R\scN such that (Yj)j=3,…,\scN=h . As some consequences of these results (1) there exist complete full non-decomposable minimal surfaces with arbitrary conformal structure and whose generalized Gauss map is non-degenerate and fails to intersect N hyperplanes of CP\scN−1 in general position. (2) There exist complete non-proper embedded minimal surfaces in R\scN, ∀\scN>3.Ministerio de Ciencia y Tecnología MTM2007-61775Ministerio de Ciencia y Tecnología MTM2007-64504Junta de Andalucía P09-FQM-508

    Complete minimal surfaces and harmonic functions

    Get PDF
    We prove that for any open Riemann surface N and any non constant harmonic function h : N → R, there exists a complete conformal minimal immersion X : N → R3 whose third coordinate function coincides with h. As a consequence, completeminimal surfaceswith arbitrary conformal structure andwhose Gauss map misses two points are constructed.Ministerio de Educación y Ciencia MTM2007-61775Ministerio de Educación y Ciencia MTM2007-64504Junta de Andalucía P06-FQM-01642

    Robert Burns: The Ploughman Poet in No Man´s Land

    Get PDF
    Considered by some critics and scholars as one of the pioneers of the Romantic movement in Britain, others, however, have failed to acknowledge this writer's contribution as a romantic poet leaving him in no man's land. A quarter of a millennium after his birth, Scottish poet Robert Burns, 'the man of independent mind', is still struggling to find his space in the literary canon. Was Robert Burns born in the wrong place at the wrong time asto be eligible for the label of romantic poet within the British tradition? lf that was the case, did his work be long to a Scottish tradition whose distinctive aesthetic features would have discarded his poetry from fully fitting in the Romantic movement in Britain despite sorne conspicuous similarities? This dissertation will aim to find a plausible answer to these questions by looking into relevant socio-political aspects, personal experiences and literary influences that might have helped shape Burns's style, and which would ultimately allow to determine to what extent his poetic production complies with the Romantic canon. William Wordsworth and Samuel Taylor Coleridge's Romantic manifesto Preface to Lyrical Ballads (1800) as a major exponent of formal, aesthetic and ideological aspects pertaining to Romantic poetry will be the framework of my analysis in order to assess the romantic quality of Burns's selected poetic work, while The Bard (2009), professor Robert Crawford's comprehensive biography on Robert Burns, will serve as the starting point to comprehend the complexity of the ploughman poet and his time.Algúns críticos e estudosos considerados como un dos pioneiros do movemento romántico en Gran Bretaña, pero outros non lograron recoñecer a contribución deste escritor como poeta romántico deixándoo en terra de ninguén. Un cuarto de milenio despois do seu nacemento, o poeta escocés Robert Burns, "o home da mente independente", segue loitando por atopar o seu espazo no canon literario. ¿É que Robert Burns naceu no lugar incorrecto no momento incorrecto podía ser elixido para a etiqueta de poeta romántico dentro da tradición británica? Se fose así, o seu traballo foi longo cunha tradición escocesa cuxos trazos estéticos distintivos terían descartado que a súa poesía se encaixase plenamente no movemento romántico en Gran Bretaña a pesar das semellanzas? Esta disertación terá como finalidade atopar unha resposta plausible a estas preguntas mirando aspectos sociopolíticos relevantes, experiencias persoais e influencias literarias que puideron axudar a dar forma ao estilo de Burns e que finalmente permitiría determinar en que medida a súa produción poética cumpre co Canon romántico. O marco da miña análise será o marco romántico do manifesto romántico de William Wordsworth e Samuel Taylor Coleridge Prefacio ás Lyrical Ballads(1800) como expoñente principal dos aspectos formais, estéticos e ideolóxicos relacionados coa poesía romántica para valorar a calidade romántica da obra poética seleccionada de Burns, e The Bard (2009), a ampla biografía do profesor Robert Crawford sobre Robert Burns, servirá como punto de partida para comprender a complexidade do poeta arado e da súa época

    Responsible research and innovation in science education: insights from evaluating the impact of using digital media and arts-based methods on RRI values

    Get PDF
    The European Commission policy approach of Responsible Research and Innovation (RRI) is gaining momentum in European research planning and development as a strategy to align scientific and technological progress with socially desirable and acceptable ends. One of the RRI agendas is science education, aiming to foster future generations' acquisition of skills and values needed to engage in society responsibly. To this end, it is argued that RRI-based science education can benefit from more interdisciplinary methods such as those based on arts and digital technologies. However, the evidence existing on the impact of science education activities using digital media and arts-based methods on RRI values remains underexplored. This article comparatively reviews previous evidence on the evaluation of these activities, from primary to higher education, to examine whether and how RRI-related learning outcomes are evaluated and how these activities impact on students' learning. Forty academic publications were selected and its content analysed according to five RRI values: creative and critical thinking, engagement, inclusiveness, gender equality and integration of ethical issues. When evaluating the impact of digital and arts-based methods in science education activities, creative and critical thinking, engagement and partly inclusiveness are the RRI values mainly addressed. In contrast, gender equality and ethics integration are neglected. Digital-based methods seem to be more focused on students' questioning and inquiry skills, whereas those using arts often examine imagination, curiosity and autonomy. Differences in the evaluation focus between studies on digital media and those on arts partly explain differences in their impact on RRI values, but also result in non-documented outcomes and undermine their potential. Further developments in interdisciplinary approaches to science education following the RRI policy agenda should reinforce the design of the activities as well as procedural aspects of the evaluation research

    Tourism and productivity: Case study of the hotel and catering industry in the Andalusian region

    Get PDF
    The object of this paper is to analyse the situation and evolution of the productivity of the tourism industry in the Andalusian region, and more specifically of the hotel and catering branch, relating it to the organisational structure of its businesses. First of all, the issue of the definition and limitation of the concept of productivity applied to the services sector is addressed, as traditionally this concept is focused on manufacturing, and the different ways of measuring and the analysis methods are reviewed. Then, using the accounting information provided by the Balances Centre of Andalusia (CBA), the general features of the organisational structure of the hotel and catering industry in de Andalusian region, stratifying the samples by the size of the companies and examining the medium size of the Andalusian hotel and catering businesses. Once the organisational structure of the sector is analysed, it is related to the state and evolution of its productivity, using a simple ratio between the brute added value and the personnel expenses, and completing this analysis with a relative efficiency index, the Baldwin efficiency index, with which the technical efficiency of each company is compared to the mass of most efficient companies. As a result of this research it is observed that the productivity indexes increase as web as the size of the companies and during the considered period, especially in the case of the medium sized and large companies. Nevertheless, these productivity increases are less relevant than the increase of employment, especially in case of smaller companies.

    Digital Competence and Literacy: Developing New Narrative Formats. The «Dragon Age: Origins» Videogame

    Get PDF
    The approach of this article is centered on the concepts of digital competence and new narrative formats. We aim to apply these dimensions to the videogame «Dragon Age Origins», winner of the 2009 videogame of the year award. Its features - plot, characters and interactivity – make it ideal reading material in other formats and are highly motivational for young people. The development of digital competence signifies new literacy, and it is necessary to find new stimulating resources that combine the fun and formative dimensions. Equally relevant are multimodal texts (Kress & Van Leeuwen, 2001), especially new narrative formats that imply social progress, as the ways of reading are different. The texts have acquired new formats with the same quality as books but they sometimes motivate users more. This is the case of «Dragon Age Origins», a dark heroic fantasy role-playing game set in a unique world containing a story to be read and experienced. Our analysis of the videogame discusses whether it should be considered a form of reading or not

    El SERS como sensor de pH en entornos nanométricos

    Get PDF
    La Espectroscopia SERS (Surface-Enhanced Raman Spectroscopy) se caracteriza por la enorme intensificación de la señal Raman de una molécula cuando se encuentra en las proximidades de una superficie metálica rugosa a escala nanométrica. Se trata, por tanto, de una técnica de alta sensibilidad que permite el registro de muestras a muy baja concentración y además, de alta selectividad, ya que únicamente aquellas moléculas que presenten un centro capaz de interaccionar con el metal, como un par de electrones libres o un grupo funcional con carga negativa, son las que producen intenso efecto SERS. Actualmente, es una técnica que cada vez se utiliza más como herramienta analítica para la detección e identificación molecular a nivel de trazas, del orden de ppb, o incluso de moléculas individuales, y con aplicación en diferentes áreas de interés como son el medio ambiente, la medicina o la bioquímica, para el control de contaminantes ambientales2, glucosa en sangre3 o secuenciación de péptidos4, respectivamente. Sin embargo, una de las aplicaciones más novedosas del SERS es como medidor óptico de pH a escala nanométrica.5 Esto es posible en aquellas moléculas que presentan, además de un centro de interacción con el metal, un grupo funcional que se vea afectado por el pH del medio y que no interviene en el proceso de adsorción superficial como es el caso de la molécula de carbendazim. Carbendazim (MBC) es un derivado del bencimidazol donde el hidrógeno imidazólico es sustituido por un grupo carbamato, el cual presenta un enlace NH sensible al pH del medio, mientras que la interacción con la superficie metálica se produce, principalmente, a través del nitrógeno aromático del anillo imidazólico. Experimentalmente se han registrado los espectros SERS de MBC en coloide de plata en un rango de pH entre 2-12. Las nanopartículas de plata se han obtenido a partir de una disolución de AgNO3 utilizando el hidrocloruro de hidroxilamina como agente reductor.2 Con objeto de conocer la asignación vibracional de las bandas del espectro, se han calculado las frecuencias vibracionales de cada una de las especies iónicas y de la forma neutra de MBC tanto aisladas como unidas a un átomo de plata mediante métodologías DFT. De esta forma, las dos bandas registradas en la región de 1200 cm-1, 1230 y 1270 cm-1, cuyas intensidades son sensibles al pH del medio, se han asignado a la deformación en el plano del enlace NH amídico e imidazólico, respectivamente. La relación de intensidad entre estas dos bandas frente al pH da como resultado una dependencia lineal. Por tanto, podría utilizarse este dispositivo como un nanosensor óptico capaz de medir el pH local de forma continua en un rango de 6-14, en aquellos ambientes donde es difícil medir el pH de forma convencional como son en células animales o vegetales y en tejidos dañados como control de lesiones tumorales.6 Moskovits, M. Rev. Mod. Phys. 1985, 57, 783. 2 López-Tocón, I.; Otero, J.C.; Arenas, J.F.; Garcia-Ramos, J.V.; Sanchez-Cortes, S. Anal. Chem. 2011, 83, 2518. 3 Kong, K.V.; Ho, C.J.H.; Gong, T.X.; Olivo, M. Biosensor & Bioelectronics 2014, 56, 186. 4 Garrell, R.L. Anal. Chem. 1989, 61, 401. 5 Bishnoi, S.; Rozell, C.; Levin, C.; Hallas, N. NanoLett. 2006, 6, 1687. 6 Vaupel, P.; Kallinowski, F.; Okunieff, P. Cancer Res. 1989, 49, 6449.Universidad de Málaga. Campus e Excelencia Internacional Andalucía Tech
    corecore