155 research outputs found

    New avenues for increasing yield and stability in C3 cereals: exploring ear photosynthesis

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    Small grain cereals such as wheat, rice and barley are among the most important crops worldwide. Any attempt to increase crop productivity and stability through breeding implies developing new strategies for plant phenotyping, including defining ideotype attributes for selection. Recently, the role of non-foliar photosynthetic organs, particularly the inflorescences, has received increasing attention. For example, ear photosynthesis has been reported to be a major contributor to grain filling in wheat and barley under stress and good agronomic conditions. This review provides an overview of the particular characteristics of the ear that makes this photosynthetic organ better adapted to grain filling than the flag leaf and revises potential metabolic and molecular traits that merit further research as targets for cereal improvement. Currently, the absence of high-throughput phenotyping methods limits the inclusion of ear photosynthesis in the breeding agenda. In this regard, a number of different approaches are presented

    Fast Visible-Light Photopolymerization in the Presence of Multiwalled Carbon Nanotubes: Toward 3D Printing Conducting Nanocomposites

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    [EN] A new photoinitiator system (PIS) based on riboflavin (Rf), triethanolamine, and multiwalled carbon nanobutes (MWCNTs) is presented for visible-light-induced photopolymerization of acrylic monomers. Using this PIS, photopolymerization of acrylamide and other acrylic monomers was quantitative in seconds. The intervention mechanism of CNTs in the PIS was studied deeply, proposing a surface interaction of MWCNTs with Rf which favors the radical generation and the initiation step. As a result, polyacrylamide/MWCNT hydrogel nanocomposites could be obtained with varying amounts of CNTs showing excellent mechanical, thermal, and electrical properties. The presence of the MWCNTs negatively influences the swelling properties of the hydrogel but significantly improves its mechanical properties (Young modulus values) and electric conductivity. The new PIS was tested for 3D printing in a LCD 3D printer. Due to the fast polymerizations, 3D-printed objects based on the conductive polyacrylamide/CNT nanocomposites could be manufactured in minutes.The authors are thankful for technical and human support provided by IZO-SGI SGIker of UPV/EHU. The authors would like to thank the European Commission for financial support through funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement no. 823989

    Monitoring of the Eyjafjallajökull volcanic aerosol plume over the Iberian Peninsula by means of four EARLINET lidar stations

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    Lidar and sun-photometer measurements were performed intensively over the Iberian Peninsula (IP) during the eruption of the Eyjafjallajökull volcano (Iceland) in April–May 2010. The volcanic plume reached all the IP stations for the first time on 5 May 2010. A thorough study of the event was conducted for the period 5–8 May. Firstly, the spatial and temporal evolution of the plume was described by means of lidar and sun-photometer measurements supported with backtrajectories. The volcanic aerosol layers observed over the IP were rather thin (<1000 m) with a top height up to 11–12 km. However, in some cases at the beginning of the period the thickness of those layers reached several kilometers in Évora and Madrid. The optical thicknesses associated to those layers were rather low (between 0.013 and 0.020 in average over the whole period), with peak values near 0.10 detected on 7 May. Secondly, the volcanic aerosols were characterized in terms of extinction and backscatter coefficients, lidar ratios, Ångström exponents and linear particle depolarization ratio. Lidar ratios at different sites varied between 30 and 50 sr without a marked spectral dependency. Similar extinction-related Ångström exponents varying between 0.6 and 0.8 were observed at different sites. The temporal evolution of the backscatter-related Ångström exponents points out a possible decrease of the volcanic particle size as the plume moved from west to east. Particle depolarization ratios on the order of 0.06–0.08 confirmed the coexistence of both ash and non-ash particles. Additionally, profiles of mass concentration were obtained with a method using the opposite depolarizing effects of ash particles (strongly depolarizing), non-ash particles (very weakly depolarizing), and sun-photometer observations. In Granada the ash mass concentration was found to be approximately 1.5 times higher than that of non-ash particles, and probably did not exceed the value of 200 μg m−3 during the whole event.This work is supported by the 7th Framework Programme project Aerosols, Clouds, and Trace Gases Research Infrastructure Network (ACTRIS) (grant agreement no. 262254); by the MICINN (Spanish Ministry of Science and Innovation) and FEDER funds under the project TEC2009-09106/TEC and UNPC10-4E-442, and the Complementary Actions CGL2010- 09225-E and CGL2011-13580-E/CLI; by the Spanish Ministry of Education under the project PR2011-0358. It has also been supported by FCT (Fundac˜ao para a Ciˆencia e a Tecnologia) through the National Re-equipment Program REDE/1527/RNG/2007. Jana Preißler was funded by FCT (grant SFRH/BD/47521/2008). Juan Luis Guerrero-Rascado was partially funded by FCT (grant SFRH/BPD/63090/2009) and by the Spanish Ministry of Education (grant EX2009-0700)

    Analysis of human cerebrospinal fluid monoamines and their cofactors by HPLC

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    The presence of monoamines and their cofactors (the pterins and vitamin B6 (pyridoxal phosphate (PLP))) in human cerebrospinal fluid (CSF) can be used as indicators of the biosynthesis and turnover of dopamine and serotonin in the brain. In addition, abnormalities in the CSF levels of these molecules are associated with various neurological diseases, including genetic diseases leading to dopamine and serotonin deficiency. Here, we provide a set of quantitative high-performance liquid-chromatography (HPLC) approaches to determine CSF levels of monoamines and their cofactors. This protocol describes step-by-step procedures for CSF sample preparation for the analysis of different molecules, HPLC calibration and analysis, and data quantification and interpretation. Unlike plasma/tissue/blood samples, CSF requires minimal sample preparation: in this protocol, only the analysis of PLP requires mixing with trichloroacetic acid to release the protein-bound vitamin, centrifugation, and mixing of the supernatant with phosphate buffer and sodium cyanide for derivatization in alkaline conditions. Monoamines are analyzed by HPLC with coulometric electrochemical detection (ED), pterins are analyzed by HPLC with coupled coulometric electrochemical and fluorescence detection, and PLP is analyzed by HPLC with fluorescence detection. The quantification of all compounds is achieved by external calibration procedures, and internal quality control and standards are analyzed in each run. We anticipate that investigation of dopamine and serotonin disturbances will be facilitated by measurements of these compounds in human CSF and other biological samples. The estimated time for the different procedures primarily depends on the electrochemical detector stabilization. Overnight stabilization of this detector is advised, and, after that step, preanalytical equilibration rarely exceeds 3 h

    Problemas alimentarios en adolescentes y su relación con la dieta en horario escolar

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    A study was carried out on the possible relationship between the eating habits of adolescents during school hours and the detection of eating disorders. A total of 4362 students (49.7% girls and 50.3% boys) from 16 secondary schools aged 13 to 17 years participated. Sociodemographic variables, body mass index (BMI), EAT-40 and BSQ questionnaires, as well as the types of eating and drinking of adolescents before and during the school morning on the day of the assessment were recorded. The results show significant differences between boys and girls in their concern and eating habits. Regarding BMI, 17.8% were underweight, 19.1% overweight and 6.0% obese. A percentage of 9.6% of girls and 1.7% of boys reported eating disorders. Girls always show a greater concern about food and body image, and they are also the ones who eat the least breakfast or lunch during the school day. Worry is correlated with obesity and not so much with underweight (r = .18 in EAT, and r = .30 in BSQ). No significant correlations were found with eating habits, although those who worry more eat less, but have a higher BMI. Overall, 6.3% of the girls and 3.6% of the boys did not eat at all during the entire school day. The importance of dietary habits in relation to the prevention of eating problems at this age group is discussed.Se ha realizado un estudio sobre la posible relación entre los hábitos alimentarios de los adolescentes en el horario escolar y la detección de trastornos alimentarios. Han participado 4362 alumnos/as (49.7% chicas y 50.3% chicos) de 16 colegios de secundaria, de 13 a 17 años. Se han registrado las variables sociodemográficas, el índice de masa corporal (IMC), y los cuestionarios EAT-40 y BSQ, además de los tipos de alimentación y bebida de los adolescentes antes y durante la mañana escolar el día de la evaluación. Los resultados muestran diferencias significativas entre chicos y chicas en su preocupación y en sus hábitos alimentarios. Respecto al IMC, un 17.8% tiene peso insuficiente, un 19.1% sobrepeso y un 6.0% obesidad. Un porcentaje del 9.6% en chicas y un 1.7% en chicos presentaría trastornos alimentarios. Las chicas muestran siempre mayor preocupación por la alimentación y por la imagen corporal, y también son las que menos desayunan o comen en la jornada escolar. La preocupación está correlacionada con la obesidad y no tanto con el infrapeso (r = .18 en EAT, y r = .30 en BSQ). No se han encontrado correlaciones significativas con los hábitos alimentarios, aunque quienes más se preocupan beben y comen menos, pero con un IMC superior. Como dato global, un 6.3% de las chicas y un 3.6% de los chicos no toman absolutamente nada durante todo ese horario escolar. Se discute la importancia de los hábitos en la dieta para la prevención de problemas alimentarios en estas edades

    Genetic Structure of the Spanish Population

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    <p>Abstract</p> <p>Background</p> <p>Genetic admixture is a common caveat for genetic association analysis. Therefore, it is important to characterize the genetic structure of the population under study to control for this kind of potential bias.</p> <p>Results</p> <p>In this study we have sampled over 800 unrelated individuals from the population of Spain, and have genotyped them with a genome-wide coverage. We have carried out linkage disequilibrium, haplotype, population structure and copy-number variation (CNV) analyses, and have compared these estimates of the Spanish population with existing data from similar efforts.</p> <p>Conclusions</p> <p>In general, the Spanish population is similar to the Western and Northern Europeans, but has a more diverse haplotypic structure. Moreover, the Spanish population is also largely homogeneous within itself, although patterns of micro-structure may be able to predict locations of origin from distant regions. Finally, we also present the first characterization of a CNV map of the Spanish population. These results and original data are made available to the scientific community.</p

    Analysis of the relationship between physical-healthy habits and diet with obesity in primary school students of the Province of Granada

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    La obesidad y el sobrepeso se han convertido en uno de los trastornos más importantes de la actualidad. La aparición de este tipo de trastorno se debe a la influencia de factores como la dieta desequilibrada o la falta de actividad física, factores que provocan un aumento del IMC en escolares. Este estudio se realizó sobre 161 escolares de educación primaria, de edades comprendidas entre los 10 y 12 años y pertenecientes a la provincia de Granada. Se pretende analizar la relación existente entre los parámetros de la actividad física y la calidad de la dieta con los niveles de obesidad. Los resultados mostraron que la mayor parte de la población estudiada se encontraba dentro del normopeso y en una baja proporción los alumnos presentaban una dieta de baja calidad, sin haber diferencias significativas en cuanto al género. Por otra parte, el análisis de los datos mostró que el género masculino realiza mayor actividad física y por tanto presenta menos sedentarismo que el género femenino. Como conclusión, se demuestra la necesidad de motivar a la realización de deporte, sobre todo al género femenino, además de concienciar a los jóvenes de las consecuencias del sedentarismo y la obesidad.Obesity and overweight have become one of the most important disorders nowadays. The onset of this type of disorder is due to the influence of factors such as unbalanced diet or lack of physical activity, factors that cause an increase in BMI in schoolchildren. This study was conducted on 161 schoolchildren of primary education, aged between 10 and 12 years old and belonging to the province of Granada. The aim is to analyze the relationship between physical activity parameters and diet quality with obesity levels. The results showed that participants were in a normal weight, whereas a low proportion of students presented a low-quality diet, with no significant differences by gender. On the other hand, the analysis of the data showed that males perform greater physical activity and therefore present less sedentary habits than females. In conclusion, the need to encourage students to carry out sports is demonstrated, especially in females. In addition, it is important to raise youth’s awareness on health consequences of sedentary habits and obesity

    Characterization of atmospheric aerosols for a long-range transport of biomass-burning from North America over the Iberian Peninsula

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    This work presents the characterization of atmospheric aerosols performed over the Iberian Peninsula in the framework of EARLINET for a special episode on 20th August 2007. The assessment of aerosol radiative impact requires an accurate determination of their optical and microphysical properties, which are presented here for a variety of instrumentation including passive remote sensors, as sun-photometers, and active systems both ground-based and on board CALIPSO satellite. Measurements highlight the presence of a multilayered structure with a well-defined planetary boundary layer and biomass-particles in elevated layers, extending up to 7 km asl over the central Iberian Peninsula, and even higher, up to 9 km asl, at the southeastern part of the peninsula. Lidar computations reveal a contribution to the aerosol optical depth around 10-40% for these biomass-burning particles, with backscatter-related AngströPostprint (published version
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