Consequences of using different pair-correlation funtions on the stability properties of the Homogeneous Cooling State for a monodisperse system of near-elastic disks

We show the differences in the stability properties of the Homogeneous Cooling State (HCS) of a two-dimensional monodisperse collection of rigid and near-elastic disks, obtained by using different formulae for the pair-correlation function.For an equation of state that takes into account the crystallization and ordering of the particles (and the respective pressure drop), the critical wavelength of the heat conduction mode is considerably modified in the transition zone, involving a bifurcation and an additional mode of instability. The theoretical predictions, using the improved equation of state are confirmed by numerical simulations. Nevertheless, some open questions remain

Identifikacija vinskih kvasaca postupkom PCR-RFLP bez prethodne izolacije na ploči

The population of wine yeasts during spontaneous must fermentation was characterized by direct 5.8S-ITS rDNA region amplification without previous plate isolation or enrichment. RFLP analysis was applied to each of the amplification products detected, and the corresponding yeast identifications were made. The method provides a fast and direct way of determining yeast population present during wine fermentation.Populacija vinskih kvasaca tijekom spontane fermentacije mošta karakterizirana je izravnom amplifikacijom regije 5,8S-ITS rDNA bez prethodne izolacije na ploči ili povećavanja količine. Primijenjena je RFLP analiza na svakom utvr|enom amplifikacijskom produktu te je provedena odgovarajuća identifikacija kvasca. Postupak omogućava brz i izravan put utvrđivanja populacije kvasca prisutnog u fermentaciji vina

A statistical approach to violin evaluation

Comparing violins requires competence and involves both subjective and objective evaluations. In this manuscript, vibration tests were performed on a set of 25 violins, both historical and new. The resulting bridge admittances were modeled in the low and mid-frequency ranges through a set of objective features. Once projected into the new representation, the bridge admittances of three historical violins made by Stradivari and a famous reproduction revealed high similarity. PCA highlighted the importance of signature mode frequencies, bridge hill behavior, and signature mode amplitudes in distinguishing different violins

A Review of the Main Machine Learning Methods for Predicting Residential Energy Consumption

The ability to predict future energy consumption is very important for energy distribution companies because it allows them to estimate energy needs and supply them accordingly. Consumption prediction makes it possible for those companies to optimize their processes by, for example, providing them with knowledge about future periods of high energy demand or by enabling them to adapt their tariffs to customer consumption. Machine Learning techniques allow to predict future energy consumption on the basis of the customers' historical consumption and several other parameters. This article reviews some of the main machine learning models capable of predicting energy consumption, in our case study we use a specific set of data extracted from a two-year-period of a shoe store. Among the evaluated methods, Gradient Boosting has obtained an 86.3% success rate in predicting consumption.This work was carried out under the frame of the "Towards Sustainable Intelligent Mobility: Blockchain-based framework for IoT Security" Ref. RTI2018-095390-B-C32" project. The project was supported and funded by the Spanish Ministerio de Economıa, Industria y Competitividad. Retos de investigacion, ´Proyectos I+D+i.info:eu-repo/semantics/publishedVersio

A neural network-based method for spruce tonewood characterization

The acoustical properties of wood are primarily a function of its elastic properties. Numerical and analytical methods for wood material characterization are available, although they are either computationally demanding or not always valid. Therefore, an affordable and practical method with sufficient accuracy is missing. In this article, we present a neural network-based method to estimate the elastic properties of spruce thin plates. The method works by encoding information of both the eigenfrequencies and eigenmodes of the system and using a neural network to find the best possible material parameters that reproduce the frequency response function. Our results show that data-driven techniques can speed up classic finite element model updating by several orders of magnitude and work as a proof of concept for a general neural network-based tool for the workshop. © 2023 Acoustical Society of America

Identificacion de genes expresados en Fragaria chiloensis en respuesta a Botrytis cinerea

154 p.Uno de los problemas más importantes de la post-cosecha en frutilla comercialmente cultivada, lo constituye la enfermedad pudrición gris, causada por el hongo Botrytis cinerea Pers. la que se encuentra ampliamente distribuida en más de 200 especies de importancia económica. Desde hace tiempo a Fragaria chiloensis, se le ha conocido por poseer una alta tolerancia a un gran espectro de enfermedades, incluyendo Botritis. Considerando lo anterior, se desarrolló un estudio de diversidad génica en esta especie que consistió en analizar individuos de Fragaria chiloensis provenientes de las zonas de Contulmo (región del Bio Bio), Chillán (región del Bio Bio) y Vilches (región del Maule) y compararlas con la especie comercial Fragaria x ananassa cv. Chandler, usando para ello, partidores ISSRs (inter simple secuense repeat). De las formas estudiadas de Fragaria chiloensis (Contulmo; Chillán y Vilches) la que presentó una mayor similitud fue la accesión de Contulmo (88 al 100%), seguido de Vilches y Chillán (70 al 100%). Para el caso de las muestras de Fragaria x ananassa, el grado de similitud varió desde los 50 a 100%. La diversidad genética fue representada por el coeficiente PhiPT (0,54337), el cual explica una diferenciación completa entre poblaciones. Paralelamente se realizaron ensayos de infección con Botrytis cinerea, observando que los poblaciones de Fragaria chiloensis provenientes de Chillán y Vilches al igual que Fragaria x ananassa cv. Chandler presentaron las primeras lesiones necróticas tres días post-inoculación con un 2 a 4% de cubrimiento del área foliar. Por el contrario, la accesión proveniente de Contulmo presentó las primeras lesiones al quinto día post-inoculación con un 3% de cubrimiento, siendo este más homogéneo genéticamente y mostrando una mayor tolerancia a Botrytis cinerea. En base a esto, se realizó una clasificación individual de las plantas del grupo Contulmo en donde se analizó a los 13 días post-inoculación la respuesta de F. chiloensis a la infección por B. cinerea. Se encontraron diferencias significativas (p≤ 0.01) en cuanto a respuesta, diferenciándose cinco categorías, las cuales se denominaron:altamente resistentes (AR), resistentes (R), tolerantes (T), moderadamente tolerante (MT) y susceptible (S), destacándose que la mayor parte del grupo presentó la respuesta de tolerancia (50%), seguido de la respuesta moderadamente tolerante (25%). Lo anterior, se confirma que F. chiloensis (Contulmo) posee una capacidad de tolerar la infección por parte del patógeno en estudio. A partir de estos resultados en una segunda parte se estudió los genes involucrados en la respuesta patogénica y que son expresados en F. chiloensis. Para ello, a través de la técnica HSS (hibridación subtractiva por supresión) se identificaron tanto secuencias asociadas previamente a respuesta a patógenos, como también algunas de función desconocida, o que podrían alterar la expresión de la planta en respuesta a B. cinerea. Del grupo de transcritos descritos, se encontraron dos proteínas relacionadas a patogénesis tales como, Thaumathin –like protein (FcPR5) y Mal d 1 (FcPR10). FcPR10 se expresó tanto en hojas como en frutos de Fragaria chiloensis, pero el más alto número de transcritos, se observó en los últimos. Por otra parte, FcPR5 se expresó en frutos y hojas de Fragaria chiloensis, encontrándose una mayor inducción en el número de transcritos en hojas./ ABSTRACT: One of the most important post-harvest problems in the commercial strawberry is gray mold, caused by the fungus Botrytis cinerea Pers. This pathogen has a wide host range, affecting more than 200 cultivated species. For a long time it has been known that Fragaria chiloensis has higher tolerance against to number of diseases, including Botritis. According to this a genetic diversity study was performed in this species, analyzing individuals from three different Fragaria chiloensis zone (Contulmo, Chillán and Vilches). These were compared to Fragaria x ananassa cv. Chandler using anchored primers or ISSR (inter simple sequence repeat). Among them, Contulmo presented the higher similarity (88 to 100 %) followed by Chillán and Vilches (70 to 100%). In Fragaria x ananassa the degree similarity of was between 50 and 100%. The genetic diversity was represented by the PhiPT coefficient (0.54337) which complete explains differentiation between populations. At the same time infection assays were developed, where the Fragaria x ananassa and Fragaria chiloensis plants from Chillán and Vilches developed the first necrotic lesions three days after inoculation, covering 2 to 4% of the leaf area. On the other hand in the Fragaria chiloensis group from Contulmo, the first necrotic lesions appeared five days after inoculation, covering 3% of the leaf area. This group was genetically more homogeneous and tolerant to gray mold. According to this response, the plants of this group were classified in five categories: highly resistant, resistant, tolerant, moderately tolerant and susceptible. Most of the individuals were categorized in the third (50%) and fourth (25%) group. In the second part of this study some of the genes related to the response to the pathogen in Chilean strawberry were studied. Using the Suppressive Subtractive Hybridizing technique, different sequences were identified, not only associated to pathogen response but also to plant expression changes. Two of them were studied in detail, which presented a high homology to Thaumathin –like protein (FcPR5) and Mal d 1 (FcPR10). FcPR10 was expressed in leaves and fruit of Fragaria chiloensis, but the higher number of transcripts was determined fruits. On the other hand FcPR5 was expressed in fruit and leaves of Fragaria chiloensis, but in the leaves the transcript induction was highest

Using Mechanical Metamaterials in Guitar Top Plates: A Numerical Study

Featured Application The use of mechanical metamaterials in musical instruments could be an excellent way to engineer the wood of the instrument to obtain a particular sound. It has recently been shown that the mechanical properties of thin, rectangular wooden plates can be tuned by carving them with specific patterns of perforations, effectively realising a 2D wooden mechanical metamaterial. Such a material is of great interest for the construction of musical instruments, as it could allow a new degree of creative control for makers. Furthermore, issues with the shrinking supplies of tone-woods could be alleviated as wood samples that don not meet the desired requirements could simply be altered, instead of being discarded. In this work, we study the effect of the use of these metamaterials in the soundboards of classical guitars. By way of simulations, we evaluate their impact on the modal behaviour and on the sound pressure level of the instrument, as well as on its ability to sustain the load exerted by the strings. Our results show that the metamaterials can tune the instrument's response without compromising its structural integrity. We thus conclude that the use of wooden mechanical metamaterials in the soundboards of classical guitars is feasible and, in many ways, beneficial, not the least since it opens the door to using non-traditional woods with bespoke density and stiffness

The impact of alkaline treatments on elasticity in spruce tonewood

It is commonly believed that violins sound differently when finished. However, if the role of varnishes on the vibrational properties of these musical instruments is well-established, how the first components of the complete wood finish impact on the final result is still unclear. According to tradition, the priming process consists of two distinct stages, called pre-treatment and sizing. The literature reports some recipes used by old Cremonese luthiers as primers, mainly based on alkaline aqueous solutions and protein-based glues. In this manuscript, we analyze the impact of these treatments on the mechanical properties of the material. The combination of two pre-treatments and three sizes is considered on nine different plates. We compare the vibrational properties before and after the application and assess the effects of the different primers, also supported by finite element modeling. The main outcome is that the combination of particular treatments on the violin surface before varnishing leads to changes not only to the wood appearance, but also to its vibrational properties. Indeed pre-treatments, often considered negligible in terms of vibrational changes, enhance the penetration of the size into the wood structure and strengthen the impact of the latter on the final rigidity of the material along the longitudinal and radial directions

Nuevos recursos metodológicos para el desarrollo de materialidades desde y para el diseño

The Biobased Materials Laboratory of the Faculty of Architecture and Urbanism (BioLab FAU) is an interdisciplinary and intergenerational space for educational and collaborative interaction. El Laboratorio de Materiales Biobasados de la Facultad de Arquitectura y Urbanismo (BioLab FAU) es un espacio interdisciplinario e intergeneracional de interacción formativa y colaborativa.  O Laboratorio de Materiales Biobasados do la Facultad de Arquitectura y Urbanismo (BioLab FAU) é um espaço interdisciplinar e intergeracional de interação educativa e colaborativa.&nbsp

Evaluacion del efecto de cepas nativas de Bacillus spp. en la accion de Xanthomonas capestris pv. campestris en almacigo de repollo bajo condiciones de invernadero

35 p.El objetivo general de este ensayo consistió en evaluar la acción de cepas nativas de Bacillus spp sobre la acción de la bacteria Xanthomonas campestris pv campestris en semillas y almácigos de repollo, bajo condiciones de invernadero. Las cepas nativas del biocontrolador fueron obtenidas a traves de un proyecto de la fundación de innovación agraria FIA y correspondieron a las cepas Vilcun y Antumavida, además de las cepas nativas de Bravibacillus brevis Maguellines y Maguellines II. Las cuales han demostrado una buena actividad antagonista en el control de bacterias fitopatògenas de importancia agrícola. El ensayo se realizo en los invernaderos ubicados en el sector sur-oriente del Campus Talca de la Universidad de Talca. Este estudio estuvo compuesto por 3 tratamientos, que incluyeron la aplicación de las cepas nativas solo en siembra y una paliación de las cepas nativas del biocontrolador tanto en siembra como en emergencia además de un testigo sin aplicación. A pesar de que las semillas utilizadas en el ensayo fueron obtenidas desde plantas con ataque de mancha angular, no fue posible obtener síntomas del patógeno en ninguna de las plantas de los distintos tratamientos durante el desarrollo del ensayo. Al no presentarse síntomas de la enfermedad en ninguna de las plantas del ensayo, se efectuaron diversas inoculaciones de las plantas ya sea bajo condiciones de invernadero como en condiciones controladas en laboratorio. Estas inoculaciones se realizaron con el objetivo de conseguir el desarrollo de la enfermedad en las plantas evaluadas. Entre las inoculaciones efectuadas se encuentran la aplicación del patógeno vía aspersión al follaje y la inoculación a través de heridas producidas artificialmente para que en estas penetre el patógeno a la planta. Por lo anterior se determino medir otros parámetros que pueden ser afectados por la acción del patógeno como el porcentaje de germinación. Adicionalmente considerando el posible efecto de la bacteria sobre el crecimiento se midió el número de hojas, peso y altura de las plantas. Nos e presentaron diferencias significativas de las cepas nativas de Bacillus spp, ya sea con una o dos aplicaciones, con el tratamiento testigo, en el parámetro de altura de plantas. En el estudio de emergencia de las plántulas de repollo, el tratamiento con la aplicación de las cepas nativas de Bacillus spp en siembra no presento diferencias estadísticamente significativas con el tratamiento testigo sin aplicación. En relación al peso de la plantas + sustrato se observo claramente que los tratamientos con aplicación del antagonista presentaron en sus plantas pesos superiores incluso en 50g. en comparación con el tratamiento control. En el parámetro de números de hojas por planta, el tratamiento 1 presento en promedio 1 hoja más por planta que los demás tratamientos evaluados