3,008 research outputs found
Impacts of European Biofuel Policies on Agricultural Markets and Environment under Consideration of 2nd Generation Technologies and international Trade
Even though recent discussions on food prices and indirect land use change point at potential conflicts associated with the production of biofuels the appraisal of biofuels as an effective instrument to slow down climate change and reduce energy dependency still prevails. The EU Renewable Energy Directive (EUROPEAN COMMISSION, 2009) underlines this trend by setting a target of 10% share of energy from renewable sources in the transport sector by 2020. As economic competitiveness of biofuel production is still not given in most European countries, support policies are essential to achieve this target. Second generation technologies have still not attained marketability, wherefore biofuel consumption will continue to significantly affect agricultural markets. Furthermore, biofuel trade receives more attention. Apart from Brazil the USA has evolved to one of the key biofuel producer in recent years replacing the EU as the dominant biodiesel exporter. Those developments in regions outside the EU have to be considered within the evolution of biofuel markets. The primary objective of this paper is to analyse in detail impacts of future biofuel developments on agricultural markets under several assumptions regarding the availability of 2nd generation technologies, the EU support policy framework and the EU trade policy regime. Therefore, we developed an extended version of the comparative static agricultural sector model CAPRI which covers global biofuel markets with a detailed focus on Europe. The results supplement already existing model-based impact assessments while focussing on EU Member State level and introducing global bilateral trade of biofuels based on the Armington approach. The results of our scenario analysis presented in this paper indicate that the European 2020 biofuel target will significantly affect global and European biofuel- as well as agricultural markets. Thereby, global biofuel trade will notably increase, especially flows of biodiesel from the USA and Argentina and of ethanol from Brazil into the EU will increase accentuating the net-importing position of the EU by 2020. On the agricultural markets, we can observe that additional demand caused by European biofuel production will be, on the one hand, partially compensated by substitution effects on the feed market and, on the other hand, mainly filled by increasing imports. Thus, effects on agricultural product prices will also be significant, while effects on EU agricultural production will only be marginal. This leads consequently to only marginal environmental impacts within Europe and confirm the assumption that notable environmental effects caused by EU biofuel production and consumption will mainly take place outside Europe, especially in those countries which are important producers of biofuel feedstoc
Bound states in the continuum in subwavelength emitter arrays
Ordered lattices of emitters with subwavelength periodicities support
unconventional forms of light-matter interactions arising from collective
effects. Here, we propose the realization and control of subradiant optical
states within the radiation continuum in two-dimensional lattices. We show how
bound states in the continuum (BICs) which are completely decoupled from
radiative states emerge in non-Bravais lattices of emitters. Symmetry breaking
results in quasi-BICs with greatly extended lifetimes, which can be exploited
for quantum information storage. The analytical derivation of a generalized
effective polarizability tensor allows us to study the optical response of
these arrays. We discuss how thanks to the quasi-BICs, a rich phenomenology
takes place in the reflectivity spectrum, with asymmetric Fano resonances and
an electromagnetically induced transparency window. Finally, we exploit these
lattices as quantum metasurfaces acting as efficient light polarizers
R&D expenditure in the EU: convergence or divergence?
This article examines the convergence of the R&D expenditure in
the EU28 for 2004–2015. We initially run a sigma convergence
analysis and the results show convergence in the total expenditure,
due to the behaviour of the business and higher education
sectors, despite government sector divergence. However, noticeable
differences between the EU15 and 13 EU countries are
apparent. The business enterprise sector is the main driver of
EU15 R&D convergence, whereas for the EU13 this role is played
by the government expenditure. In addition, the economic crisis
has impacted differently on both groups. The club convergence
approach allows us to explore these insights through individualized
analysis and clusterization. Results for the EU28 show two
clubs for the total expenditure, but the analysis of its components
reveals a larger grouping. Our results evidence the necessity of
revising the EU R&D policies towards greater coordination and
resources, and the implementation of new instruments, due to
the impact of this expenditure on growth, development and
integration
Design guidelines for self-assessment support for adult academic distance learning
Menendez Blanco, M., Van der Veer, G., Benvenuti, L., & Kirschner, P. A. (2011). Design guidelines for self-assessment support for adult academic distance learning. In H-J Shalin (Ed.), Constructing self-discovery learning spaces online: scaffolding and decision making technologies (pp. 169-198). Hershey, PA: IGI Global.This contribution focuses on adult distance learning. Based on experiences at the Open University of the Netherlands we investigate specific problems that our students have with self-assessment and metacognition while studying. Starting from a literature review and complementing this with available student data from our teaching research center, we developed a conceptual framework that was iteratively adjusted and assessed by a questionnaire study and interviews. This allowed us to develop design guidelines for self-assessment support in distance learning environments. These guidelines were reviewed by experts. The input from the experts was used to modify the guidelines and iterate until they were considered complete. Tangible designs (i.e., mock-ups) for each of the self-assessment methods were proposed. These tangible designs were prototyped for later evaluation. Finally, we provide our conclusions and propose recommendations for actual application and systematic design
Vasorelaxant Effect of a Baccharis trimera Infusion on Precontracted Rat Aortic Rings
Baccharis trimera (Less.) DC is a South American plant that in folk medicine is considered to produce reduction in blood pressure. One aspect of this putative
effect is the vasorelaxation. The aim of this work was to evaluate the ability of a B. trimera extract to relax rat aortic rings precontracted with noradrenaline. As
the infusion is the usual way of intake of this plant, an infusion of B. trimera was prepared using 100g of the plant (leaves) boiled in water, frozen and
lyophilized. Working solutions were prepared using different concentrations of the dried extract diluted in Krebs Henseleit solution. It was proved that the
infusion relaxed the aortic rings in a dose dependent manner 100 minutes after adding the extract to the bath. Considering as 100% the maximum contraction
achieved with noradrenaline, a relaxation of 101.1±2.3% was observed with the highest dose of the infusion used in these experiments (0.32mg/mL). While in
control rings relaxation was 12.9±2.4%. In aortic rings denuded from endothelium the percentage of vasoralaxation did not show statistically significant
differences when compared to intact rings. These data support the hypothesis of a vasorelaxant effect of this plant and constitutes the first approach to the
scientific basis of a potential antihypertensive effect
A survey study of evidence-based medicine training in US and Canadian medical schools
PURPOSE: The authors conducted a survey examining (1) the current state of evidence-based medicine (EBM) curricula in US and Canadian medical schools and corresponding learning objectives, (2) medical educators\u27 and librarians\u27 participation in EBM training, and (3) barriers to EBM training.
METHODS: A survey instrument with thirty-four closed and open-ended questions was sent to curricular deans at US and Canadian medical schools. The survey sought information on enrollment and class size; EBM learning objectives, curricular activities, and assessment approaches by year of training; EBM faculty; EBM tools; barriers to implementing EBM curricula and possible ways to overcome them; and innovative approaches to EBM education. Both qualitative and quantitative methods were used for data analysis. Measurable learning objectives were categorized using Bloom\u27s taxonomy.
RESULTS: One hundred fifteen medical schools (77.2%) responded. Over half (53%) of the 900 reported learning objectives were measurable. Knowledge application was the predominant category from Bloom\u27s categories. Most schools integrated EBM into other curricular activities; activities and formal assessment decreased significantly with advanced training. EBM faculty consisted primarily of clinicians, followed by basic scientists and librarians. Various EBM tools were used, with PubMed and the Cochrane database most frequently cited. Lack of time in curricula was rated the most significant barrier. National agreement on required EBM competencies was an extremely helpful factor. Few schools shared innovative approaches.
CONCLUSIONS: Schools need help in overcoming barriers related to EBM curriculum development, implementation, and assessment.
IMPLICATIONS: Findings can provide a starting point for discussion to develop a standardized competency framework
El diseño y testeo de aplicaciones didácticas para dispositivos móviles: el Metacubo como caso de ejemplo de investigación aplicada.
Abstract: We present a case of designing a conceptual transformation process and of applied research. We have moved from the design and discussion of the Metacube concept to its conversion into a software whose results can be applied to information management in many fields, and in fact has already found one of its conversions or mutations in applications and educational games for tablets as the Zong-Ji Kids, which stimulate mental work in children aged 6 to 9 years. The game underwent in 2012 to a process of observational testing in a laboratory with 80 children, aged 5 to 13 years. The results indicate that the symbolic simplification of the elements of design and an easily understandable interface help to understand the application and assimilation of concepts linked with the learning and reinforcement of calculation and geometric concepts. Some of them are addition and subtraction or positive, negative, increment, decrease, increasing or decreasing rotation, contiguous and opposing facets and representation of a polygon with different levels of complexity. Five years later, the big data analysis of the online application show that the design decisions made were appropriate. En este artículo pretendemos exponer un caso de diseño de un proceso de transformación conceptual y de investigación aplicada. Se ha pasado del diseño y discusión de concepto Metacubo a su conversión en un software cuyos resultados pueden aplicarse a la gestión de la información en muchos campos y que de hecho ya ha encontrado una de sus conversiones o mutaciones en aplicaciones y juegos didácticos para tablets como el Zong-Ji Kids, que estimulan el trabajo mental en niños de edades comprendidas entre los 6 y los 9 años. El juego se sometió en 2012 a un proceso de testeo observacional en laboratorio a 80 niños de edades comprendidas entre los 5 y los 13 años
Estructura del sistema frontal de cabalgamientos en el Pirineo Oriental: control estratigráfico en la geometría y secuencia de emplazamiento de los cabalgamientos
El manto del Cadí, la unidad estructural más extensa del Pirineo Oriental meridional, involucra cerca de 5 km de sucesión paleógena depositada en una cuenca de antepaís. Esta secuencia constituye un sistema petrolífero que ha sido explorado desde el año 1960 y suprayace discordantemente un basamento Paleozoico involucrado en el apilamiento antiforme que caracteriza el centro de la cordillera. En el antepaís, la sucesión paleógena presenta un espesor menor y está constituida por un conjunto de facies diferente, en general más somera. La interpretación de datos sísmicos reprocesados recientemente y su integración con datos de superficie y de sondeos son la base de un nuevo modelo estructural del área. La presencia de un espesor anómalo de una serie de rocas evaporíticas por debajo del sinclinal de Ripoll (2000m perforados en el sondeo El Serrat-1) ha sido interpretada como asociada a un cambio lateral de facies entre una formación turbidítica (Campdevànol) septentrional, la formación evaporítica de Beuda y una formación carbonática meridional (Perafita) y a su apilamiento en un dúplex
Identification of Importin 8 (IPO8) as the most accurate reference gene for the clinicopathological analysis of lung specimens
<p>Abstract</p> <p>Background</p> <p>The accurate normalization of differentially expressed genes in lung cancer is essential for the identification of novel therapeutic targets and biomarkers by real time RT-PCR and microarrays. Although classical "housekeeping" genes, such as GAPDH, HPRT1, and beta-actin have been widely used in the past, their accuracy as reference genes for lung tissues has not been proven.</p> <p>Results</p> <p>We have conducted a thorough analysis of a panel of 16 candidate reference genes for lung specimens and lung cell lines. Gene expression was measured by quantitative real time RT-PCR and expression stability was analyzed with the softwares <it>GeNorm </it>and <it>NormFinder</it>, mean of |ΔCt| (= |Ct Normal-Ct tumor|) ± SEM, and correlation coefficients among genes. Systematic comparison between candidates led us to the identification of a subset of suitable reference genes for clinical samples: IPO8, ACTB, POLR2A, 18S, and PPIA. Further analysis showed that IPO8 had a very low mean of |ΔCt| (0.70 ± 0.09), with no statistically significant differences between normal and malignant samples and with excellent expression stability.</p> <p>Conclusion</p> <p>Our data show that IPO8 is the most accurate reference gene for clinical lung specimens. In addition, we demonstrate that the commonly used genes GAPDH and HPRT1 are inappropriate to normalize data derived from lung biopsies, although they are suitable as reference genes for lung cell lines. We thus propose IPO8 as a novel reference gene for lung cancer samples.</p
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