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The comfort and safety of a cyclist are directly influenced by the vibrational behavior of the handlebar. Hence, the objective of this article is to comparatively assess the vibrational characteristics of two bicycle handlebars: one made of steel and the other made of braided composite material. The transmissibility function represents the relationship between the excitation applied to both handlebars through their stems and the corresponding response in the handle area, which was experimentally obtained by applying a random vibrating signal (constant amplitude of 0.01 g2/Hz) using a shaker. This signal was applied in a frequency range between 100 Hz and 1200 Hz, and the response was measured at one of the two cantilevered ends of the handlebar. Different sensors, including a laser vibrometer and a control accelerometer in the shaker, were utilized. The transmissibility, natural frequencies and damping functions were obtained. Subsequently, another experimental analysis was carried out with the instrumented handlebars mounted on a bicycle, placing three accelerometers and a GPS meter and traveling through a real test circuit, with a rough surface, speed bumps and areas with shaped warning bands. Power Spectral Density (PSD) curves were obtained for the steel and carbon-fiber-composite handlebars in order to quantify the signal intensity. Finally, a fatigue analysis was carried out in order to evaluate the expected life of both handlebars under the experimentally applied load, which is considered the reference cycle. This study offers a comparative analysis of the vibration behavior exhibited by steel and carbon-fiber-composite bicycle handlebars under experimentally applied load. In conclusion, data on natural frequencies, damping functions and fatigue life expectancy for both handlebar materials were obtained. Our study provides valuable insights into the vibrational behavior and performance characteristics of steel and carbon-fiber-composite bicycle handlebars, contributing to the understanding of their comfort and safety implications for cyclists.

A Trifolium fragiferum (strawberry clover) cover crop was used as an alternative for weed control under the vines in an irrigated vineyard located in a semiarid area of Northern Spain. The cover crop allowed a satisfactory and cost-effective management of weeds, without causing relevant changes in yield and grape and wine characteristics. After 4 years of study, we demonstrated that the use of a cover crop under the vines can be an economically profitable alternative to herbicide or intra-row mechanical tillage.

Background and AimsMonitoring of acute or chronic response to beta-blockers in patients with liver cirrhosis is based on the measurement of the HVPG. Our aim was to evaluate the response to beta-blockers with non-invasive techniques.Patients and MethodsThis is a prospective observational study. Consecutive patients with an indication of primary or secondary prophylaxis of variceal bleeding who did not meet exclusion criteria were included. Acute response and chronic response were evaluated. Baseline and after acute and chronic response hepatosplenic measurements of TE and ARFI were obtained. Contrast-enhanced Doppler ultrasound was performed before and after acute and chronic responses.ResultsFrom June 2015 to May 2018, 55 patients (14 with exclusion criteria) were included. We analyzed 41 patients, mean age 57 (SD: 8), 82.9% men, alcohol 43.9%, children A/B/C 78%/17.1%/4.9%, and 87.8% on primary prophylaxis. In all, the acute response was performed and was positive in 68.3% (CI 95: 55–85%). The chronic response was performed in 30 (73.2%) and was positive in 36.7% (CI 95: 18–55%). Basal measurements significantly related to acute response were spleen TE [responders 58.4 (SD: 23.0) KPa vs. non-responders 75 (SD: 0) KPa; p = 0.02] and damping index [non-responders 0.96 (0.8) vs. responders 0.44 (0.4), p = 0.01], and with chronic response, the spleen TE [responders 58.1 (SD: 21.4) KPa vs. non-responders 73.2 (SD: 5.5) KPa; p = 0.02], and damping index [non-chronic responders 0.8 (0.7) vs. chronic responders 0.4 (0.4), p = 0.04]. A spleen TE ≥ 74 KPa had a high sensitivity of 100% and specificity of 60% and a high NPV100% for predicting poor acute response to beta-blockers. The damping index > 0.6 showed moderate sensitivity of 67% and specificity of 69% with a high NPV of 82% for predicting poor acute response to beta-blockers. The combination of both measurements for predicting poor acute response to beta-blockers had an AUC of 0.8 (CI 95: 0.5–0.9). A spleen TE ≥ 74 KPa had a high sensitivity of 87% and specificity of 71% with a high NPV of 71% for predicting poor chronic response to beta-blockers. A damping index > 0.6 had moderate sensitivity of 60%, specificity of 82%, and NPV of 56% for predicting poor chronic response to beta-blockers. The combination of both measurements for predicting poor chronic response to beta-blockers had an AUC of 0.8 (CI 95: 0.7–0.9).ConclusionSpleen TE and damping index can identify a subgroup of patients with poor acute or chronic response to beta-blockers.

In this work, we analyzed a variety of metrics derived from Laser Doppler Vibrometry (LDV) characterization of 3D printed rectangular prisms. The metrics of interest were natural frequencies and amplitudes of first and second bending vibration modes, equivalent elastic moduli, damping ratios and areas of transmissibility functions. To explore the influence of printing process parameters on the dynamical behavior and, therefore, on the aforementioned metrics, 48 different combinations were considered, including build orientation, raster angle, nozzle temperature, print speed and layer height as relevant parameters. Thus, 96 polylactic acid (PLA) rectangular prisms were fabricated and LDV characterization was carried out. Based on the equivalent elastic modulus metrics, it was possible to corroborate the influence of printing process parameters on the mechanical performance, being raster angle, build orientation and nozzle temperature the most influential parameters. Likewise, the analysis of damping ratios served to assess the degree of interfilament bonding of 3D printed rectangular prisms. Thus, rectangular prims that exhibited high damping ratios also showed evident lack of adhesion between deposited filaments. Low damping ratios and, therefore, superior interfilament bonding was connected with on edge build orientation, high nozzle temperature (220 °C) and low print speed (60 mm/s) for specimens fabricated using 0° as raster angle. The analyses of areas of transmissibility functions and amplitudes of vibration modes also confirmed a better transmission of excitation (i.e., larger areas and higher amplitudes) for optimally fabricated parts, that is, specimens featuring relatively high equivalent elastic moduli and low damping ratios. Moreover, the application of Classical Laminate Theory to establish the relationships between elastic modulus and damping ratio with raster angle confirmed low temperature (200 °C) and high print speed (120 mm/s) resulted in low elastic modulus a high damping ratios and, therefore, poor interfilament bonding. The present findings confirm LDV is a powerful technique in the characterization of additively manufactured products, being able to discriminate different mechanical behaviors as well as the degree of interfilament bonding. Despite of their simplicity, the metrics derived from LDV characterization represent an attractive tool for both research and industrial applications.

El trabajo que se expone en este estudio es el resultado de una investigación realizada con un grupo de niñas y niños de 2-3 años en una escuela infantil del Ayuntamiento de Madrid y se basa en identificar la significatividad de las diferentes acciones e interacciones que se realizan en unos espacios lúdicos denominados instalaciones de juego, así como la cuestión de si el ser humano interioriza lo que proviene de la experiencia exterior a través de las acciones o “exterioriza” lo que se origina desde su propio mundo interior mediante éstas. En el enfoque metodológico empleado se ha adoptado el modelo de investigación-acción siguiendo una secuencia de ciclos dividida en cuatro momentos: planificación, acción, observación y reflexión, favoreciendo la participación de la comunidad educativa implicada en el proyecto. Las relaciones vinculares que se crean a través de los encuentros estables en estos espacios de encuentro, ofrecen la oportunidad de compartir procesos de acompañamiento cultural y transformación que contribuyen a descubrir la posibilidad de mejorar la realidad educativa, incluyendo e implicando a la comunidad de pertenencia y referencia.

In this study, we explored the suitability of laser-scanning vibrometry (LSV) for evaluation of the mechanical behavior of rectangular prisms produced by Fused Filament Fabrication (FFF). Our hypothesis was that LSV would be able to discriminate the mechanical behavior of specimens fabricated with different process parameters combinations. Build orientation, raster angle, nozzle temperature, printing speed and layer thickness were the process parameters of interest. Based on a factorial design of experiment approach, 48 different process parameter combinations were taken into account and 96 polylactic acid (PLA) rectangular prisms were fabricated. The characterization of their dynamical behavior provided frequency data, making possible the computation of an equivalent elastic modulus metric. Statistical analysis of the equivalent elastic modulus dataset confirmed the significant influences of raster angle, build orientation and nozzle temperature. Moreover, multivariate regression models served to rank, not only the significant influences of individual process parameters, but also the significant quadratic and cubic interactions between them. The previous knowledge was then applied to generate an ad hoc model selecting the most important factors (linear and interactions). The predicted equivalent elastic moduli provided by our ad hoc model were used in modal analysis simulations of both 3D printed rectangular prisms and a complex part. The simulated frequencies thus obtained were generally closer to the experimental ones (≤11%), as compared to modal analysis simulations based on internal geometry modelling (≤33%). The use of LSV appears very promising in the characterization of the mechanical behavior and integrity of 3D printed parts. Other additive manufacturing technologies may benefit from the use of this technique and from the adoption of the presented methodology to test, simulate and optimize the properties of 3D printed products.

Aim: The present systematic review aims to provide an overview about the impact of cover crops on vegetative growth and productive parameters of vineyards. Methods and results: A systematic review was made using Scopus-index journals along 20 years (1999-2018). The selection was independently done by two researchers, selecting a total of 272 published papers related to cover crops in vineyard. Each article was categorized according to its theme and a metadata was created, considering all relevant information from an agronomic point of view. Conclusion: It was observed that the use of cover crops can reduce vine vegetative growth that, in turn, could be used to keep the incidence of fungal diseases at a low level, like grey mould. In general, this practice does not clearly affect vineyard yield, nor grape juice parameters like total soluble solids (TSS) or titratable acidity (TA). Cover crops can decrease to some extent vineyard pests, especially Cicadellidae. Only and punctually in the central summer months the covers can sometimes cause water stress in the vineyard. Significance of the study: This review allows to systematically synthesize the information on cover crops and their effects on vineyard agronomic performance. Thus allowing using the most suitable cover for the objectives sought in the growing conditions that are had.

This work seeks to synthesise the knowledge on the use of cover crops in vineyards in the last 20 years, emphasising on the one hand, soil characteristics such as nutrition, organic carbon, structure or erosion and, on the other hand, environmental factors such as soil and biodiversity in vineyards, and gas emissions. A systematic review was made using Scopus-index journals for the past 20 years (1999 - 2018). The selection was independently done by two researchers, selecting a total of 272 published papers related to cover crops in the vineyard. Each article was categorised according to its theme and metadata were created, considering all relevant information from an agro-ecological point of view. The use of cover crops has a positive effect on the vineyard by increasing soil organic carbon (SOC), improving water infiltration and aggregate stability, and reducing erosion and greenhouse gases emission to the atmosphere. Furthermore, there is an increase in biodiversity, both in soil and the vineyard. Finally, cover crops do not constitute as a rule a major competition for nutrients to the vines except for nitrogen when grass covers are used. Contrarily, legume cover crops generally increase N in the soil, although its availability for plants is not immediate. This review constitutes an objective tool to help growers when considering the use of cover crops in vineyards that, based in a systematic review, provides relevant information depending on the characteristics of the growing condition of the vineyard.

This study aims to evaluate the interest of using an under-vine cover crop as a sustainable management tool replacing herbicides or tillage to control weeds, evaluating its effects on yield and berry parameters in a semi-arid climate. The performance of Trifolium fragiferum as an under-vine cover crop was evaluated in 2018 and 2019 in a Merlot vineyard in Traibuenas (Navarra, Spain). This trial showed that the soil under the vines was covered by 80 % of the cover crop in August 2018 and 100 % in Aug 2019, with clover (T. fragiferum) comprising around 26 % and 70 % of the cover crop surface, respectively. The presence of the cover crop only reduced the number of shoots in the second year, although both years there was an increment in water stress. Neither yield, cluster weight nor berry weight were affected by the presence of the under-vine cover crop. Similarly, no changes in grape composition were observed. The use of T. fragiferum-like cover crops under the vine allows for better control of weeds, provided a good installation is achieved. In the first two years, this cover crop reduced vegetative growth and increased water deficit slightly. However, no changes in yield and grape composition were observed. In a context of herbicide suppression and search for sustainable management, under-vine clover cover crops constitute a viable alternative in semi-arid regions provided drip irrigation can be applied.

La expresión de las emociones colabora en la construcción de las diferentes identidades que conviven y se comparten en el ámbito educativo a través de la alteridad. Se propone la narración de la experiencia artística mediante la creación de un espacio-metáfora para ofrecer visibilidad al relato colectivo que describe los procesos de autoconstrucción del “yo” y del “nosotros” que reconoce esas emociones. Durante la acción performativa, los participantes aportan objetos simbólicos y ofrecen palabras significativas para representar hechos de su vida que dicen el lugar del otro. Esta propuesta interdisciplinar considera el contexto educativo como “arquitectura sensible” para el encuentro que permite construir identidades relacionales.

SÍNTESIS. En el presente estudio se recoge una investigación realizada en escuelas infantiles 0-3 años del Ayuntamiento y la Comunidad de Madrid. En ella se pretende demostrar la necesidad de ofrecer propuestas pedagógicas en este ámbito que contribuyan a potenciar el sentido educativo de esta etapa y permitan y favorezcan el desarrollo cultural y social de los procesos vitales de la infancia: las relaciones sociales, comunicativas y afectivas, el aprendizaje significativo y la elaboración de los procesos simbólicos mediante la creación de contextos de encuentro y relación a través del juego libre. Es decir, la propuesta didáctica se basa en la manera de enriquecer simbólicamente la cualidad de los ambientes de juego proyectados para la infancia, utilizando las instalaciones como espacios concebidos a partir del encuentro entre una propuesta estética del arte contemporáneo y la fundamentación pedagógica inspirada en la práctica psicomotriz Aucouturier. Este «diálogo» posibilita y favorece el juego presimbólico y simbólico en un contexto relacional.

Se presenta, a través de la metáfora del bordado, una experiencia de arte intergeneracional y relacional que reconoce la creación de puentes afectivos entre pasado y presente para generar conexiones a través de la meoria emocional y la representación del recuerdo. Este encuentro conforma un relato construido mediante breves narraciones dese la voz, pensamiento y testimonio femenino (abuela-nieta, madre-hija, hermana-hermana) que cruzan sus biografías en un tiempo compartido para el cuidado de un ser querido con Alzhimer. La acción simbólica de bordar juntas, acto íntimo de comunicación mediado por la palabra y el silencio, la mirada, la escucha y el tacto, posibilita la reconstrucción de una identidad que la enfermedad diluye y permite ser resignificada en cada lugar, objeto, persona y comprtamiento social. Como en la trma de la vida, los hilos que se tejen juntos posibilitan el vínculo y la permanencia a una historia común a la que arraigarse en el tejido del Ser, enhebrado nombres, pensamientos, emociones y sucesos que nos definen en relación con Otro y en la alteridad. Más allá de la estimulación cognitiva, la acción artística del bordado revela el universo simbólico del conocimiento y los significados de cuidar y ser cuidado.

The space configured within the psychomotor practice is a device conceived so that children can thus experience a journey of psychological maturation regarding conflict management in interpersonal relations. The goal is also for them to go from action to thought by means of free and spontaneous play. Summarising, becoming aware of their existence and their life project. The configuration of Education contexts through new contemporary art proposals-installations and body implications- can favour cognitive processes, the elaboration of meanings, affective and emotional development, peer relations, and sensitive attitudes stemming from sensorimotor and symbolic play. These activities are based on the symbolic transformations that children make regarding their own bodies, objects and spaces. This way, they interpret these contexts as vital meaning, offering the characteristic metaphors of children’s culture as a manifestation and visualisation of all possible narratives.

Este artículo desarrolla una experiencia puesta en práctica durante el curso, 2006/07, en la asignatura de dramatización, que se imparte dentro del plan de estudios de la especialidad de educación infantil, en el Centro Superior de Estudios Universitarios La Salle, adscrito a la Universidad Autónoma de Madrid. La propuesta va dirigida a ofrecer un planteamiento metodológico que diversifi ca la oferta de los trabajos teóricos y prácticos, que los alumnos deben elaborar al cursar la asignatura, tanto desde sus contenidos como desde la manera de desarrollarlos. Con este formato, se pretende aumentar el interés y la curiosidad de los estudiantes, tanto por el propio trabajo, como por el de sus compañeros.

Enter-Arte, grupo de trabajo del Movimiento de Renovación Pedagógica «Acción Educativa», está interesado en generar, desarrollar y gestionar proyectos artísticos innovadores que acerquen el arte a la escuela y trasladen el arte infantil al medio socio-cultural. Lugar de encuentro y reflexión entre docentes que, vinculados con otros profesionales, se interesan por la creación y la investigación artística en el ámbito educativo, la búsqueda de nuevos lenguajes visuales y plásticos en la escuela, el desarrollo de metodologías activas y globalizadoras en aula. Desde su fundación en 1998, el grupo Enter-Arte ha llevado a cabo y expuesto diversos proyectos, en los que se valoraban los procesos de trabajo y la participación de toda la comunidad educativa. En este artículo se ofrece un recorrido histórico y justificado de todas estas acciones, con una mayor extensión sobre el último proyecto llevado a cabo en el año 2004.

Choosing the most appropriate rootstock(s) is a key decision for the profitability of vineyards; therefore, there must be a sufficient range of rootstocks in the market adapted to different environmental conditions and production objectives. However, rootstock-breeding programs have been scarce in recent decades, and most of the rootstocks used today were bred a century ago, when the needs of the sector were very different from today. In this work, we aimed to evaluate new rootstock candidates before their introduction in the market. An agronomic evaluation was conducted on eight novel rootstock genotypes obtained from the first generation of the cross-pollination of 41 B Millardet et de Grasset (41 B) and 110 Richter (110 R) grafted with 'Syrah' and 'Tempranillo' and planted in a typical vineyard of the Ebro Valley in Spain. During the four consecutive growing seasons (2016e2019), growth, yield and berry composition parameters at harvest were collected. A linear mixedeffects model was constructed, considering year and block as random effects. Multiple factor analysis and hierarchical clustering on principal components were performed to establish clusters of genotypes with similar behaviour. The rootstock candidates showed a very wide performance range compared to their parents. The trial allowed us to identify two very promising candidates (RG8 and RG10), whose registration as commercial rootstocks is already in progress. [ABSTRACT FROM AUTHOR]