Student-led learning through collaborative videos on hydrology and soil erosion

Este trabajo pretende dar un impulso a la modernización educativa mediante un esfuerzo colaborativo dirigido por los propios estudiantes. Mediante la combinación de las Tecnologías de la Información y la Comunicación (TIC) y las nuevas redes sociales usadas frecuentemente por los estudiantes (Twitter, Periscope, Youtube, Instagram, Pinterest por citar algunos) se intenta facilitar la enseñanza junto con el aprendizaje a través de nuevos enfoques tecnológicos que ayuden a analizar y comprender los procesos hidrológicos y erosivos en el suelo. Mediante la elaboración de sus propios vídeos sobre diferentes temas elegidos por los propios estudiantes, éstos identifican los objetivos del aprendizaje en la materia según su importancia y asumen cierta responsabilidad de su propio proceso de aprendizaje . Los temas elegidos han sido: (i) el movimiento del frente de humedad en diferentes tipos de suelo; (ii) la retención de agua en las cubiertas vegetales sobre edificios, conocidas también como techos verdes; y (iii) la infiltración de agua en el suelo desde una perspectiva más general. Los estudiantes, en grupos de 2 a 6 personas, han diseñado un guión para los vídeos, han filmado los vídeos y, finalmente, los han alojado en el espacio de la plataforma moodle y en redes sociales (en particular en Twitter). Esta colección de vídeos constituye una nueva herramienta de enseñanza-aprendizaje, que permite primero a los distintos grupos de estudiantes profundizar en su aprendizaje sobre un tema en concreto, y después enseñar sus progresos al resto de estudiantes de los demás grupos para un aprendizaje del colectivo.This study aims to give an impulse to the modernization of the learning process through a collaborative effort, led by students themselves. Through the combination of Information and Communication Technologies (ICT) and new social media used frequently by students (Youtube, Instagram, Pinterest,…) the learning process was enhanced while at the same time promoting learning through new technological approaches that helped to analyze and understand processes related to hydrology and soil erosion. Through the elaboration of their own videos own different topics chosen by student groups, they identify the learning objectives of the course subject according to its importance and assume responsibilities of their own learning process. The chosen course themes were: (i) the movement of the wetting front in soils of different texture; (ii) water retention in green roofs; (iii) field water infiltration practical. The students, in groups of 2 to 6 were assigned to design the scenario for the videos, shooting and finally its diffusion through moodle and social media (in this case Twitter was selected). This collection of educative videos will constitute a new learning tool for following courses. It contributed to the group to deepen its knowledge about a particular course theme, and show their progress to their fellow students so that the learning process would be collective

A 300-year record of sedimentation in a small tilled catena in Hungary based on δ13C, δ15N, and C/N distribution

Purpose Soil erosion is one of the most serious hazards that endanger sustainable food production. Moreover, it has marked effects on soil organic carbon (SOC) with direct links to global warming. At the same time, soil organic matter (SOM) changes in composition and space could influence these processes. The aim of this study was to predict soil erosion and sedimentation volume and dynamics on a typical hilly cropland area of Hungary due to forest clearance in the early eighteenth century. Materials and methods Horizontal soil samples were taken along two parallel intensively cultivated complex convex-concave slopes from the eroded upper parts at mid-slope positions and from sedimentation in toe-slopes. Samples were measured for SOC, total nitrogen (TN) content, and SOMcompounds (δ13C, δ15N, and photometric indexes). They were compared to the horizons of an in situ non-eroded profile under continuous forest. On the depositional profile cores, soil depth prior to sedimentation was calculated by the determination of sediment thickness. Results and discussion Peaks of SOC in the sedimentation profiles indicated thicker initial profiles, while peaks in C/N ratio and δ13C distribution showed the original surface to be ~ 20 cm lower. Peaks of SOC were presumed to be the results of deposition of SOC-enriched soil from the upper slope transported by selective erosion of finer particles (silts and clays). Therefore, changes in δ13C values due to tillage and delivery would fingerprint the original surface much better under the sedimentation scenario than SOC content. Distribution of δ13C also suggests that the main sedimentation phase occurred immediately after forest clearance and before the start of intense cultivation with maize. Conclusions This highlights the role of relief in sheet erosion intensity compared to intensive cultivation. Patterns of δ13C indicate the original soil surface, even in profiles deposited as sediment centuries ago. The δ13C and C/N decrease in buried in situ profiles had the same tendency as recent forest soil, indicating constant SOM quality distribution after burial. Accordingly, microbiological activity, root uptake, and metabolism have not been effective enough to modify initial soil properties

Use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency-high magnitude simulated rainfall events

[EN] Soil and water losses due to agricultural mismanagement are high and non-sustainable in many orchards. An experiment was set up with rainfall simulation at 78 mm h(-1) over 1 hour on 20 paired plots of 2 m(2) (bare and straw covered) in new persimmon plantations in Eastern Spain. Effects of straw cover on the control of soil and water losses were assessed. An addition of 60% straw cover (75 gm(-2)) resulted in delayed ponding and runoff generation and consequently reduced water losses from 60% to 13% of total rainfall. The straw cover reduced raindrop impact and thus sediment detachment from 1014 to 47 g plot(-1) h(-1). The erosion rate was reduced from 5.1 to 0.2 Mg ha-(1) h(-1). The straw mulch was found to be extremely efficient in reducing soil erosion rates.The research projects GL2008-02879/BTE, LEDDRA 243857 and RECARE-FP7 (no. 603498, http://recare-project.eu/) supported this research.Cerdà, A.; González-Pelayo, Ó.; Giménez Morera, A.; Jordán, A.; Pereira, P.; Novara, A.; Brevik, EC.... (2016). Use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency-high magnitude simulated rainfall events. Soil Research. 54(2):154-165. https://doi.org/10.1071/SR15092S15416554

Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe

Pathogenetics of alveolar capillary dysplasia with misalignment of pulmonary veins.

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is a lethal lung developmental disorder caused by heterozygous point mutations or genomic deletion copy-number variants (CNVs) of FOXF1 or its upstream enhancer involving fetal lung-expressed long noncoding RNA genes LINC01081 and LINC01082. Using custom-designed array comparative genomic hybridization, Sanger sequencing, whole exome sequencing (WES), and bioinformatic analyses, we studied 22 new unrelated families (20 postnatal and two prenatal) with clinically diagnosed ACDMPV. We describe novel deletion CNVs at the FOXF1 locus in 13 unrelated ACDMPV patients. Together with the previously reported cases, all 31 genomic deletions in 16q24.1, pathogenic for ACDMPV, for which parental origin was determined, arose de novo with 30 of them occurring on the maternally inherited chromosome 16, strongly implicating genomic imprinting of the FOXF1 locus in human lungs. Surprisingly, we have also identified four ACDMPV families with the pathogenic variants in the FOXF1 locus that arose on paternal chromosome 16. Interestingly, a combination of the severe cardiac defects, including hypoplastic left heart, and single umbilical artery were observed only in children with deletion CNVs involving FOXF1 and its upstream enhancer. Our data demonstrate that genomic imprinting at 16q24.1 plays an important role in variable ACDMPV manifestation likely through long-range regulation of FOXF1 expression, and may be also responsible for key phenotypic features of maternal uniparental disomy 16. Moreover, in one family, WES revealed a de novo missense variant in ESRP1, potentially implicating FGF signaling in the etiology of ACDMPV

De la collaboration clinique en milieu hospitalier au montage d’un projet de recherche en psychologie

International audienc

Evaluation of the free–free resonant frequency method to determine stiffness moduli of cement-treated soil

The objective of this research is to validate the free–free resonant frequency method and its interpretation to determine the small-strain stiffness moduli of cement-treated soil. In this testing method, a cylindrical soil specimen is laid on top of a soft foam layer to approach fully free boundary conditions. Next, an accelerometer is placed in contact with one end of the specimen to measure vibrations, while the other end is impacted with a light hammer. Then, the small-strain moduli can be evaluated from the density, the dimensions and the fundamental frequency of the vibrations. Factors that could affect the interpretation include the actual boundary conditions of the sample, the interference of the accelerometer on the vibrational response of the sample and the aspect ratio of the sample given by the ratio diameter to length. In order to verify the reliability of the measurements, the free–free resonant frequency method was compared with a more robust technique like the laser Doppler vibrometer. Furthermore, the impact of the sample’s aspect ratio was investigated through a numerical modal analysis from which correction factors were also proposed to improve the reliability of the interpretations