Wetting of Nematic Liquid Crystals on Crenellated Substrates: A Frank–Oseen Approach

We revisit the wetting of nematic liquid crystals in contact with crenellated substrates, studied previously using the Landau–de Gennes formalism. However, due to computational limitations, the characteristic length scales of the substrate relief considered in that study limited to less than 100 nematic correlation lengths. The current work uses an extended Frank–Oseen formalism, which includes not only the free-energy contribution due to the elastic deformations but also the surface tension contributions and, if disclinations or other orientational field singularities are present, their core contributions. Within this framework, which was successfully applied to the anchoring transitions of a nematic liquid crystal in contact with structured substrates, we extended the study to much larger length scales including the macroscopic scale. In particular, we analyzed the interfacial states and the transitions between them at the nematic–isotropic coexistence

Is there a relationship between ferric-chelate reductase activity in roots of poncirus trifoliata and leaf chlorophyll contents?

Poncirus trifoliata is a citrus rootstock very sensitive to Fe deficiency. This deficiency is very common in crops grown in calcareous soils due to the detrimental effect of bicarbonate ion. Higher plants have distinct behaviours when faced with Fe chlorosis, and several mechanisms may be activated under Fe shortage. The aim of this study was to investigate the activity of ferric-chelate reductase (FC-R), a key enzyme in Fe uptake, and to verify whether relationships with leaf chlorophyll contents could be established. Plants were grown in nutrient solutions without Fe (0 μM Fe), with 1 μM Fe, with 120 μM Fe and with 120 μM Fe plus CaCO3 (1 g L-1). Total leaf chlorophyll in young and mature leaves was determined using a calibration model based on a relationship between SPAD readings and concentration of chlorophyll (r2=0.95; P<0.01). The activity of FC-R was determined in roots apexes and several biomass parameters in shoots (number of leaves, height, dry and fresh weight) and roots (dry and fresh weight) were evaluated at the end of the experiment. The activity of FC-R increased in plants grown without iron (0 μM Fe). The results about the relations between root FC-R and leaf chlorophyll are discussed.info:eu-repo/semantics/publishedVersio

La importancia del grupo familiar en la formación de la ciudadanía a través del desarrollo del sentimiento de comunidad

Se pretende compartir los descubrimientos previos de un estudio donde se destaca la importancia del desarrollo del sentimiento de comunidad dentro del ambiente familiar para la formación ciudadana, entendiendo a la ciudadanía como una construcción social, comprometida y participativa, que puede encontrar en el ambiente familiar un espacio más de formación. Se consideró necesario contar con un sustento teórico elaborado desde la teoría psicológica brindada por Adler (1912) en articulación con la propuesta teórica de Ciudadanía Democrática Radical, sugerida por Mouffe (1999). El método propuesto para su realización obedece a algunas técnicas y estrategias brindadas por la metodología cualitativa, con un enfoque fenomenológico para la reconstrucción de historias de vida, las cuales permitieron recuperar en el discurso de los informantes elementos significantes para la investigación, que finalmente fueron analizados e interpretados

Cross-Correlations in Meat Prices in Brazil: A Non-Linear Approach Using Different Time Scales

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Computing the phase diagram of binary mixtures: a patchy particle case study

We investigate the phase behaviour of 2D mixtures of bi-functional and three-functional patchy particles and 3D mixtures of bi-functional and tetra-functional patchy particles by means of Monte Carlo simulations and Wertheim theory. We start by computing the critical points of the pure systems and then we investigate how the critical parameters change upon lowering the temperature. We extend the Successive Umbrella Sampling method to mixtures to make it possible to extract information about the phase behaviour of the system at a fixed temperature for the whole range of densities and compositions of interest.Comment: 13 pages, 13 figure

Responses of tomato (Solanum lycopersicum L.) plants to iron deficiency in the root zone

Iron deficiency induces a yellowing in the aerial part of plants, known as iron chlorosis, and reduces the growth, yield, and quality of the fruits. Understanding plant response to iron deficiency is essential for agronomic management. This study decoded the temporal response of tomato plants (Solanum lycopersicum L.) to iron deficiency by quantifying different vegetative parameters. Subapical root swelling in the first 2.0 mm and several shoot and root growth parameters were measured in plants grown in a nutrient solution with and without Fe, on different dates designated as days after transplantation (DAT). Correlations between the total chlorophyll concentration in young leaves and 22 morphological and physiological parameters were also calculated. The plants grown in the absence of Fe had a higher number of secondary roots at 3 DAT, compared to control plants. On the same date, subapical root swelling was also observed, particularly at 1.5 and 2.0 mm from the root tip. Those plants also had a lower chlorophyll content in young leaves and a higher ferric-chelate reductase activity (FCR; EC 1.16.1.17) in the roots. At 9 DAT, the overall vegetative performance (plant height, fresh weight of stems and leaves) was negatively affected. At the end of the experiment (14 DAT), significant correlations were found between chlorophyll and the studied parameters. In conclusion, tomato plants experienced a cascade of responses to Fe deficiency throughout nine days: firstly, root lateralization increased; later, root swelling was observed, and a decrease in leaf chlorophyll content was registered associated with an increase in root FCR. At the end, the biomass of tomato plants decreased.info:eu-repo/semantics/publishedVersio

A força da cultura em Bento de Jesus Caraça

Resumo: Num período de intensa reflexão filosófica sobre a cultura, também em Portugal vários autores escreveram sobre esse tema. Bento de Jesus Caraça, cientista e intelectual progressista, dedicou-lhe várias conferências, centrando na cultura a sua intervenção social e política, na fase histórica de implantação e de afirmação do Estado Novo salazarista. Neste artigo é analisada a interpretação da cultura e o poder de transformação que o autor lhe atribui, podendo situar-se na área de reflexão da filosofia da cultura, a partir dos pressupostos em que assenta.Palavras-chave: Cultura; Civilização; Filosofia da cultura; Historicismo

Implementing machine learning for data breach detection

Privata. ai is a User and Entity Behavior Analytics (UEBA) application used for the detection of data breaches in an organization. By tracking down the usual access to personal and sensitive data, it becomes much easier to detect an outlier. These anomalies could result in a real threat to the company’s data security and must, therefore, be promptly detected and addressed. This paper focuses on the managerial challenges that arise from the increasing threat of data breaches and how machine learning could help in protecting organizations from them. For this purpose, large part of the challenge came from understanding the unique specificities of these attacks and finding an appropriate machine learning method to detect them. Given the fact that the data used to train the models was randomly generated, the results should be taken with caution. Nevertheless, the models used for this paper should be taken as a basis for the future development of the software