644 research outputs found

    ABA-overproduction response under salinity

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    [SPA] Con el fin de comprender la influencia de la fitohormona ácido abscísico (ABA) en la adaptación al riego salino, dos líneas transgénicas independientes de tomate (Solanum lycopersicum L.), sp12 y sp5, que sobreexpresan constitutivamente el gen NCED1 (codifica para la enzima que cataliza un paso limitante en la biosíntesis de ABA) y la variedad silvestre Ailsa Craig, se han estudiado en experimentos o bien i) como planta entera o ii) como portainjerto bajo condiciones control y de estrés salino. Aunque la expresión constitutiva de NCED disminuye el crecimiento bajo condiciones control, minimiza los efectos producidos por la sal (planta completa) y mejora significativamente el crecimiento cuando se usa como portainjerto. El análisis de la savia xilemática de raíz mostró que los fenotipos resultantes bajo las diferentes condiciones de cultivo eran difíciles de explicar en términos de sobreproducción de ABA. Para intentar explicar estos resultados se llevó a cabo un análisis de expresión de un conjunto de genes relacionados con hormonas y estrés mediante PCR cuantitativa, así como un estudio transcriptómico mediante microarrays en la raíz. Los resultados sugieren que la sobreexpresión de NCED parece alterar diversas rutas de señalización, derivando en una respuesta adaptativa al estrés que podría ayudar a explicar los fenotipos observados. [ENG] With the aim of better understanding the influence of the plan hormone abscisic acid (ABA) in adaptation to saline irrigation, two independent transgenic tomato (Solanum lycopersicum L.) lines, sp12 and sp5, overexpressing constitutively NCED1 (the enzyme that catalyzes a key rate-limiting step in ABA biosynthesis) and the wild type Ailsa Craig, have been studied in experiments either i) as whole plants or ii) as rootstocks under control and salinity conditions. While NCED overexpression penalizes growth under control conditions, it minimized the effect of salinity (whole plants) or significantly improved plant growth and yield when used as rootstocks. The analysis of the root xylem sap revealed that the phenotypes resulting under the different conditions were difficult to explain in terms of ABA overproduction. With the aim of explaining these results, the expression of a set of hormone and stress associated genes (analysed by real time PCR) as well as a transcriptomic analysis (by using one-color microarray) were performed in roots. The results suggest that NCED overexpression seems to alter several signalling pathways leading to stress adaptive responses that could help to explain the observed phenotypes.The authors thank Andrew J. Thompson from Cranfield University, the NCED seeds set. This work was supported by CICYT-FEDER (project AGL2011-27996) and European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289365(ROOTOPOWER project)

    Root ABA signalling in salinized tomato

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    [SPA] Con el fin de comprender la influencia de la fitohormona ácido abscísico (ABA) en la adaptación al riego salino, dos líneas transgénicas independientes de tomate (Solanum lycopersicum L.), sp12 y sp5, que sobreexpresan constitutivamente el gen NCED1 (codifica para la enzima que cataliza un paso limitante en la biosíntesis de ABA) y la variedad silvestre Ailsa Craig, se han estudiado en experimentos o bien i) como planta entera o ii) como portainjerto bajo condiciones control y de estrés salino. Aunque la expresión constitutiva de NCED disminuye el crecimiento bajo condiciones control, minimiza los efectos producidos por la sal (planta completa) y mejora significativamente el crecimiento cuando se usa como portainjerto. El análisis de la savia xilemática de raíz mostró que los fenotipos resultantes bajo las diferentes condiciones de cultivo eran difíciles de explicar en términos de sobreproducción de ABA. Para intentar explicar estos resultados se llevó a cabo un análisis de expresión de un conjunto de genes relacionados con hormonas y estrés mediante PCR cuantitativa, así como un estudio transcriptómico mediante microarrays en la raíz. Los resultados sugieren que la sobreexpresión de NCED parece alterar diversas rutas de señalización, derivando en una respuesta adaptativa al estrés que podría ayudar a explicar los fenotipos observados. [ENG] With the aim of better understanding the influence of the plan hormone abscisic acid (ABA) in adaptation to saline irrigation, two independent transgenic tomato (Solanum lycopersicum L.) lines, sp12 and sp5, overexpressing constitutively NCED1 (the enzyme that catalyzes a key rate-limiting step in ABA biosynthesis) and the wild type Ailsa Craig, have been studied in experiments either i) as whole plants or ii) as rootstocks under control and salinity conditions. While NCED overexpression penalizes growth under control conditions, it minimized the effect of salinity (whole plants) or significantly improved plant growth and yield when used as rootstocks. The analysis of the root xylem sap revealed that the phenotypes resulting under the different conditions were difficult to explain in terms of ABA overproduction. With the aim of explaining these results, the expression of a set of hormone and stress associated genes (analysed by real time PCR) as well as a transcriptomic analysis (by using one-color microarray) were performed in roots. The results suggest that NCED overexpression seems to alter several signalling pathways leading to stress adaptive responses that could help to explain the observed phenotypes.The authors thank Andrew J. Thompson from Cranfield University, the NCED seeds set. This work was supported by CICYT-FEDER (project AGL2011-27996) and European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289365(ROOTOPOWER project).. -2010-5 European Union)

    Evaluation of cadmium bioaccumulation-related physiological effects in salvinia biloba:An insight towards its use as pollutant bioindicator in water reservoirs

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    Free-living macrophytes play an important role in the health of aquatic ecosystems. Therefore, the use of aquatic plants as metal biomonitors may be a suitable tool for the management of freshwater reservoirs. Hence, in this study, we assessed the effects of cadmium (Cd) in Salvinia biloba specimens collected from the Middle Paraná River during a 10-day experiment employing artificially contaminated water (100 μM Cd). S. biloba demonstrated a great ability for Cd bioaccumulation in both the root-like modified fronds (named “roots”) and the aerial leaf-like fronds (named “leaves”) of the plants. Additionally, Cd toxicity was determined by the quantification of photosynthetic pigments (chlorophylls a and b, and carotenoids), flavonoids, and soluble carbohydrate contents in S. biloba over time (1, 3, 5, 7, and 10 days). In general, deterioration was more pronounced in leaves than in roots, suggesting a greater implication of the former in long-term Cd sequestration in S. biloba. Deleterious effects in the appraised parameters were well correlated with the total amount of Cd accumulated in the leaves, and with the qualitative changes observed in the plants’ phenotype during the 10-day metal exposure assay. The flavonoids and carotenoids in leaves were highly affected by low Cd levels followed by root carbohydrates. In contrast, chlorophylls and root flavonoids were the least impacted physiological parameters. Therefore, our results demonstrate that S. biloba displays dissimilar organ-linked physiological responses to counteract Cd phytotoxicity and that these responses are also time-dependent. Though further research is needed, our work suggests that easy-handled physiological data obtained from autochthonous free-floating S. biloba specimens may be used as a valuable tool for metal-polluted water biomonitoring

    PERFIL ACTUAL DEL AGRICULTOR ECOLÓGICO EN LA COMARCA DEL ALTO GUADALENTÍN (MURCIA)

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    Ecological farmer’s Profile of the Alto Guadalentín in the Murcia Region. Within the Murcia County, the Region of Alto Gudalentín represents 7.01% of the whole murcian farming dedicated to produce ecological products. In this project we analyse the farmer’s profile using data from the Alto Guadalentín Ecological Farming Council. The final result shows that 50% of the farmers in this region became ecological farmers from traditional farmers being the financial factor one of the key factors to switch from traditional to ecological farming. The higher percentage of ecological farmers of Alto Guadalentín, nearly 35%, are between 46 and 55 years old, 28% are between 36 and 45 years old and only 12.28% of the farmers in this region are under 36 years of age. Almost 87% of the Alto Guadalentín farmers don’t belong to any farming association.Dentro de la Comunidad de Murcia, la Comarca del Alto Guadalentín representa el 7,01% del total de la superficie murciana dedicada a agricultura ecológica. En este trabajo se analiza el perfil del agricultor ecológico en la Comarca del Alto Guadalentín para ello se realizaron encuestas al 74,03% de los agricultores de la zona, según los datos obtenidos del Consejo Agricultura Ecológica de la Región de Murcia. Los resultados obtenidos revelan que casi el 50% de los agricultores de la Comarca del Alto Guadalentín se inició como agricultor ecológico mediante un cambio del sistema de agricultura convencional hacia la agricultura ecológica, siendo el factor económico con casi el 57% uno de los principales motivos para pasar de un tipo de agricultura a otro. Por otro lado, el mayor porcentaje de los agricultores ecológicos del Alto Guadalentín (35%) se encuentran en un intervalo de edad entre 46 y 55 años. El 28% tienen entre 36 y 45 años y casi el 25% tienen una edad superior a 56 años. Solamente el 12,28% de los agricultores de la Comarca tienen edades inferiores a los 36 años. El 87% de los agricultores del Alto Guadalentín no pertenecen a ningún tipo de asociación

    Digital rubric-based assessment of oral presentation competence with technological resources for preservice teachers

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    This study focuses on e-assessment of oral presentation competence using technology resources in a model that combines project-based learning and flipped learning. This study uses a digital rubric to assess oral presentation competence in different situations of progressive assessment for 99 preservice teachers, situations in which participation was either optional or compulsory. Findings show that the digital rubric used at various times is a methodology and a technology that facilitates the feedback process and dialogue between teachers and students about the assessment criteria. The results support future decisions for methodological design of formative assessment appropriate to online learning environments.   Evaluación basada en rúbricas digitales de la competencia de presentación oral con recursos tecnológicos para profesorado en formación Este estudio está dirigido a la e-evaluación de la competencia de presentación oral utilizando recursos tecnológicos en un modelo activo que combina aprendizaje basado en proyectos y aula invertida. Este estudio aplica el uso de una rúbrica digital para la evaluación de la competencia en presentación oral en diferentes situaciones de evaluación activa y progresiva de 99 futuros docentes en las que la participación es opcional u obligatoria. Los resultados muestran que la rúbrica digital empleada en varios momentos es una metodología y una tecnología que facilita el proceso de retroalimentación y diálogo entre docentes y estudiantes sobre los criterios de evaluación. Los resultados apoyan futuras decisiones de diseño metodológico de evaluación formativa apropiadas en entornos de aprendizaje online

    Generating airborne ultrasonic amplitude patterns using an open hardware phased array

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    Holographic methods from optics can be adapted to acoustics for enabling novel applications in particle manipulation or patterning by generating dynamic custom-tailored acoustic fields. Here, we present three contributions towards making the field of acoustic holography more widespread. Firstly, we introduce an iterative algorithm that accurately calculates the amplitudes and phases of an array of ultrasound emitters in order to create a target amplitude field in mid-air. Secondly, we use the algorithm to analyse the impact of spatial, amplitude and phase emission resolution on the resulting acoustic field, thus providing engineering insights towards array design. For example, we show an onset of diminishing returns for smaller than a quarter-wavelength sized emitters and a phase and amplitude resolution of eight and four divisions per period, respectively. Lastly, we present a hardware platform for the generation of acoustic holograms. The array is integrated in a single board composed of 256 emitters operating at 40 kHz. We hope that the results and procedures described within this paper enable researchers to build their own ultrasonic arrays and explore novel applications of ultrasonic holograms.This research was funded by the Government of Navarre (FEDER) 0011-1365-2019-000086 and from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101017746, TOUCHLESS

    Reemplazo de la estabilización tartárica por frío en las bodegas: El uso de carboximetil celulosa, poliaspartato de potasio y resinas intercambiadoras de iones

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    El tratamiento de los vinos antes del embotellado para evitar la precipitación de las sales del ácido tartárico es un paso importante y común durante la producción del vino. La estabilización en frío es el tratamiento de estabilización más utilizado, y aunque ha demostrado ser efectiva, presenta algunas desventajas significativas. Estas son las razones por las cuales se están introduciendo otros productos y metodologías en las bodegas. Algunas de estas nuevas técnicas implican la reducción de la concentración de ácido tartárico y/o potasio en los vinos. Otras son técnicas aditivas y utilizan coloides protectores o inhibidores de la cristalización de las sales. En este estudio, se han tratado con carboximetilcelulosa, con poliaspartado de potasio y con resina de intercambio iónico vinos blancos, rosados y dos tipos diferentes de vinos tintos. Se estudiaron las características enológicas y cromáticas de los vinos y se evaluaron también sensorialmente. Los resultados indican que las características sensoriales y cromáticas se mantuvieron en los vinos (en comparación con un vino de control no tratado) con el uso de la carboximetilcelulosa y el poliaspartato, no detectándose diferencias en la mayoría de los casos en una prueba sensorial triangular en el caso de la carboximetilcelulosa y siendo los vinos tratados con poliaspartato de potasio evaluados positivamente

    Kinetics of antibodies in sera, saliva, and urine samples from adult patients with primary or secondary dengue 3 virus infections

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    SummaryObjectivesThe kinetics of three serological markers (IgM, IgA, and IgG) in serum, saliva, and urine samples from adult patients with primary or secondary dengue infection were studied.DesignSerum, saliva, and urine samples were collected from 22 patients with clinical and confirmed dengue 3 virus infection during the outbreak in Havana City in 2001. They were tested by capture IgM (MAC-ELISA), IgA (AAC-ELISA), and IgE (EAC-ELISA) and IgG ELISA inhibition method (EIM) to detect specific dengue antibodies.ResultsSimilar kinetics were observed in IgM, IgA, and IgG antibodies in saliva and IgA and IgG in urine samples from secondary cases compared with kinetics in serum samples, although the values were lower. No IgG antibody was detected in saliva and urine samples in primary cases and IgM antibody was not detected in urine samples from either primary or secondary infection. All secondary cases were positive for IgG in saliva and urine samples at day 7. The kinetics of specific IgE antibodies in primary and secondary cases were different.ConclusionsThe kinetics of three serological markers (IgM, IgA, and IgG) in serum, saliva, and urine samples from adult patients with primary or secondary dengue 3 virus infection were studied for the first time, showing its behavior and usefulness in dengue virus diagnosis. The specific IgE could play a role as a serological marker in secondary infections
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